UBC Theses and Dissertations

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UBC Theses and Dissertations

A two-phase anaerobic digestion process (UASB-UASB) for simulated sewage sludge Fongsatitkul, Prayoon 1992

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A T W O - P H A S EA N A E R O B I CD I G E S T I O NP R O C E S S ( U A S B - U A S B )F O RS I M U L A T E DS E W A G E S L U D G Eb yP R A Y O O NF O N G S A T I T K U LB . S c . ( S a n i t a t i o n ) ,M a h i d o l U n i v e r s i t y ,1 9 7 5M . S c . ( E n v i r o n m e n t a lT e c h n o l o g y a n d M a n a g e m e n t ) ,A s i a n I n s t i t u t eo fT e c h n o l o g y ,1 9 7 8A T H E S I SS U B M I T T E DI NP A R T I A LF U L F I L L M E N TO FT H ER E Q U I R E M E N T SF O RT H E D E G R E EO FD O C T O RO F P H I L O S O P H Yi nT H EF A C U L T YO FG R A D U A T ES T U D I E S( D e p a r t m e n to fC i v i l E n g i n e e r i n g )W ea c c e p tt h i s t h e s i sa s c o n f o r m i n gt o t h er e q u i r e d s t a n d a r dT H E U N I V E RT Y O FB R I T I S HC O L U M B I AA p r i l1 9 9 2© P R A Y O O NF O N G S A T I T K U L ,1 9 9 2I n p r e s e n t i n gt h i s t h e s i si np a r t i a lf u l f i l m e n t o f t h er e q u i r e m e n t sf o ra n a d v a n c e dd e g r e e a tt h e U n i v e r s i t y o fB r i t i s h C o l u m b i a ,I a g r e et h a t t h eL i b r a r y s h a l lm a k e i tf r e e l y a v a i l a b l ef o rr e f e r e n c ea n d s t u d y .If u r t h e ra g r e et h a t p e r m i s s i o nf o r e x t e n s i v ec o p y i n g o ft h i s t h e s i s f o r s c h o l a r l yp u r p o s e sm a y b eg r a n t e d b y t h eh e a d o fm yd e p a r t m e n to rb yh i s o r h e rr e p r e s e n t a t i v e s .I t i su n d e r s t o o dt h a t c o p y i n g o rp u b l i c a t i o no f t h i s t h e s i s f o r f i n a n c i a l g a i ns h a l l n o tb ea l l o w e dw i t h o u tm y w r i t t e np e r m i s s i o n .D e p a r t m e n to fC i v i lE n g i n e e r i n gT h eU n i v e r s i t y o f B r i t i s hC o l u m b i aV a n c o u v e r ,C a n a d aD a t e/D E - 6 ( 2 1 8 8 )A B S T R A C TT h e o b j e c t i v e so ft h i sr e s e a r c hp r o g r a m w e r e t o d e m o n s t r a t e t h e f e a s i b i l i t ya n de f f e c t i v e n e s so fa“ t w o - p h a s e ”a n a e r o b i c s e w a g es l u d g e s t a b i l i z a t i o n( U A S B - U A S B )p r o c e s s .A b e n c h - s c a l ee x p e r i m e n t ,c o n s i s t i n g o ft w oc o m p l e t e l ym i x e d s e a l e du p f l o wa n a e r o b i c( A - U A S Ba n dM - U A S B ) r e a c t o r s , d e s i g n e dt oo p e r a t ei n s i d ea w a l k - i nt e m p e r a t u r e c o n t r o l l e dr o o ma t3 5 0C ,w a se m p l o y e d .T h e s y s t e mw a sf i r s t s e e d e d a n da c c l i m a t i z e d ,a n dt h e n u s e di n a s e r i e so fd i f f e r e n t e x p e r i m e n t a lr u n s ,e m p h a s i z i n gt h ee f f e c t s o fi n f l u e n tS l u d g eR a t i o( S R )o f p r i m a r yt o s e c o n d a r ys l u d g e s a n d R e c y c l eR a t i o( R R )o ff l u i d i z e ds l u d g ef r o m s l u d g e b l a n k e tp o r t i o no ft h e r e a c t o r ,o n p r o c e s sp e r f o r m a n c e .T h ev i c i n i t yo f “ b e s tk n o w n ”r u n n i n gc o n d i t i o nw a sl o c a t e db y a na p p l i c a t i o no f 2b y 2f a c t o r i a ld e s i g na n dR e s p o n s eS u r f a c eM e t h o d( R S M ) .M a x i m u ms y s t e ml o a d i n g c a p a c i t y ,o p t i m u mo p e r a t i n g c o n d i t i o n s ,a n d s y s t e mf a i l u r e / r e c o v e r yp r o c e s s w e r ef u r t h e r i n v e s t i g a t e d .T h er e s u l t so f t h i s r e s e a r c hs t u d ys h o w e dt h a t at w o - p h a s eU A S B - U A S Bp r o c e s sa p p e a r e dt o b e f e a s i b l ea n de f f e c t i v ei n s t a b i l i z i n gs e w a g es l u d g ea th i g h o r g a n i cl o a d i n gr a t e s ,w h i l em a i n t a i n i n ga n a c c e p t a b l el e v e lo fs u p e r n a t a n tq u a l i t ya n d C H4g a sp r o d u c t i o n .T h e s y s t e mh a da h i g h p o t e n t i a lt o r e c o v e re f f e c t i v e l y ,a f t e ra s e r i o u sf a i l u r e ,b y a p p l y i n ga s t e p - l o a d i n gr e d u c t i o na n di n t e r n a lr e c i r c u l a t i o n( R R ) a p p r o a c h .T h e“ T w o - p h a s e ”c o n c e p th a s p r o v e dt ob es u c c e s s f u li n t r e a t i n gs e w a g es l u d g e .H y d r o l y s i sa c i d i f i c a t i o np r e d o m i n a t e di n t h eA - U A S B ,w h i l ea c e t o g e n e s i s - m e t h a n o g e n e s i s1 1d o m i n a t e di nt h eM - U A S B .M o s to ft h er e a c t i o n s o c c u r r e da t t h e l o w e rp a r t s( s l u d g eb l a n k e ta n d b e d )o f b o t h r e a c t o r s .Ac o m b i n a t i o no f s y s t e mh y d r a u l i ca n do r g a n i co v e r l o a d i n gi nt h eM - U A S Breactorw a sa m a j o r c a u s eo fp r o c e s s f a i l u r e .T h i s w a si n d i c a t e db y a w a s h o u to f M L V S S , a ni n c r e a s ei n t h et o t a l V F Ac o n c e n t r a t i o n ,a r e d u c t i o ni nt h e s y s t e mr e m o v a le f f i c i e n c y ,ac e s s a t i o no f CH4g a s p r o d u c t i o n ,ad r o po f p H ,a n d a n i n c r e a s ei n t o t a lV F A / a l k a l i n i t yr a t i o .A p p l y i n gat w o - s t e p approach t oi n c r e a s et h e HRT o f t h e M - U A S Bb y1 . 5a n d5 . 8 t i m e st h a to ft h ep r o c e s sf a i l u r e HRT( M - U A S B ) ,t h es y s t e mC O D( s o l )r e m o v a le f f i c i e n c yr e c o v e r e de x p o n e n t i a l l yw i t ha ni n c r e a s ei nH R T ,w h i l et h e CH4 g a s p r o d u c t i o nr e c o v e r e dl o g a r i t h m i c a l l y(r2=O.81-O.99). T h e o p t i m u m o p e r a t i n g HRTsf o rt h e MU A S B ,r e g a r d i n gC O D( s o l )r e m o v a le f f i c i e n c ya n d CH4 g a sp r o d u c t i o n , w e r e2 a n d2 . 7d a y sd u r i n gt h em a x i m i z a t i o na n dr e c o v e r yp e r i o d ,r e s p e c t i v e l y .F o rd e s i g np u r p o s e s ,t h eo p t i m u mo p e r a t i n g HRTs o f1a n d2d a y sa sw e l la s RR o f2 a n d3t i m e s thato ft h ei n t l u e n t f l o wr a t e are r e c o m m e n d e df o rt h eA -a n dM - U A S Br e a c t o r s ,r e s p e c t i v e l y .Areactord i a m e t e rt o h e i g h tr a t i oo f1 : 8t o 1 : 1 0 ,a n da no r g a n i cl o a d i n grateo f1 9k gCOD(total)/m3-da t3 5°C ,w i t ht h ef e e ds l u d g er a t i oo f4t o1 ( 8 0 / 2 0 )a r ea l s or e c o m m e n d e d .M o d i f i e dd e s i g nc r i t e r i a ,s t a r t - u pa n da c c l i m a t i z a t i o np r o c e s s e s ,a n ds y s t e mo p e r a t i o n ,f o rt h et w o - p h a s ea n a e r o b i cd i g e s t i o no fs e w a g es l u d g e (UASBU A S B ) ,w e r ef i n a l l yd e v e l o p e d .1 1 1• V I I• x l i• x•x v i i.1.1.2.6.6.9• 1 1• 2 1• 2 1• 2 6•2 8• 3 33 33 33 53 53 63 93 93 94 14 6T A B L E O FC O N T E N T SA B S T R A C Ti iT A B L E O F C O N T E N T Si vL I S TO F T A B L E SL I S TO FF I G U R E SA C K N O W L E D G E M E N T SL I S T O F A B B R E V I A T I O N S1 . I N T R O D U C T I O N1 . 1 R e s e a r c hN e e d sa n d B a c k g r o u n d1 . 2R e s e a r c hO b j e c t i v e sa n d A p p r o a c h2 . B A C K G R O U N DA N D B R I E FL I T E R A T U R ER E V I E W2 . 1 A n a e r o b i c S l u d g eD i g e s t i o n2 . 2O p e r a t i n gP a r a m e t e r sa n d R e s p o n s e s2 . 3 A n a e r o b i cP r o c e s sD e v e l o p m e n t3 . S Y S T E MS E T - U P A N DO P E R A T I O N3 . 1R a t i o n a l ea n dD e s i g n C r i t e r i a3 . 2E x p e r i m e n t a lA p p a r a t u s a n dO p e r a t i o n3 . 3 S y n t h e t i c S l u d g eP r e p a r a t i o n4 . E X P E R I M E N T A LP R O G R A M S4 . 1 A c c l i m a t i z a t i o nP r o c e s s4 . 1 . 1S y s t e mS e e d i n ga n dS t a r tu p L o a d i n g4 . 1 . 2 S y s t e mO p e r a t i n gC o n d i t i o n s4 . 2E x p e r i m e n t a lD e s i g n4 . 2 . 1 O p t i m u m“ B e s tk n o w n ”O p e r a t i n gC o n d i t i o n s4 . 2 . 2M a x i m u mL o a d i n gR a t ea n dR e c o v e r yP e r i o d s4 . 2 . 3S a m p l i n gP r o g r a ma n d A n a l y t i c a lT e c h n i q u e s4 . 2 . 3 . 1S a m p l i n gP r o g r a m4 . 2 . 3 . 2A n a l y t i c a lT e c h n i q u e s4 . 2 . 4 D a t aa n d S t a t i s t i c a lA n a l y s i si v5 . 2 . 2 . 35 . 2 . 2 . 44 74 74 74 84 95 05 65 86 06 06 16 66 97 98 08 38 39 19 39 49 91 0 41 1 11 2 26 . C O N C L U S I O N SA N DR E C O M M E N D A T I O N S1 3 36 . 1C o n c l u s i o n s6 . 2R e c o m m e n d a t i o n sR E F E R E N C E S1 3 9A P P E N D I XA1 4 7S y n t h e t i cS l u d g eP r e p a r a t i o na n dS y s t e mS e t - u p1 4 75 . R E S U L T SA N DD I S C U S S I O N5 . 1 A c c l i m a t i z a t i o np r o c e s s5 . 1 . 1 D e v e l o p m e n to f t h eA c c l i m a t i z a t i o nP r o c e s s5 . 1 . 1 . 1 B e h a v i o u ra n dR e s p o n s e5 . 1 . 1 . 2A c c l i m a t i z a t i o nA l t e r n a t i v e s( a ) W a s h o u t P h e n o m e n o n( b )S y s t e m P e r f o r m a n c e5 . 1 . 2 C o n c l u s i o n s5 . 2E x p e r i m e n t a lD e s i g n5 . 2 . 1 O p t i m u m“ b e s tk n o w n ” O p e r a t i n gC o n d i t i o n5 . 2 . 1 . 1E f f e c t sa n dI n t e r a c t i o no fS l u d g eR a t i o( S R )a n dR e c y c l e R a t i o ( R R )5 . 2 . 1 . 2 “ B e s tK n o w n ”R u n n i n gC o n d i t i o n5 . 2 . 1 . 3T w o - p h a s eS e p a r a t i o n( U A S B - U A S B )5 . 2 . 1 . 4C o n c l u s i o n s5 . 2 . 2M a x i m u mL o a d i n gC a p a c i t ya n dR e c o v e r yP r o c e s s5 . 2 . 2 . 1M a x i m u mL o a d i n gC a p a c i t y( a ) P r o c e s sF a i l u r e( b )M a x i m u mL o a d i n gR a t e5 . 2 . 2 . 2R e c o v e r yP r o c e s s( a ) R e c o v e r yP e r i o d( b )S y s t e m R e c o v e r yB a s i cE x p e r i m e n t a lK i n e t i c sO p t i m u mL o a d i n gC a p a c i t y( a )C a s e1 :O v e r a l lS y s t e m L o a d i n gC a p a c i t y( b ) C a s e2 : O p t i m u mL o a d i n gC a p a c i t yo fAM - U A S B s5 . 2 . 2 . 5 C o n c l u s i o n s1 1 1a n d1 1 61 1 85 . 2 . 3D e v e l o p m e n to fS y s t e mD e s i g nC r i t e r i a5 . 2 . 3 . 1O p t i m u mS y s t e mP e r f o r m a n c ea n d F e a s i b i l i t y1 2 25 . 2 . 3 . 2M o d i f i c a t i o no f D e s i g nC r i t e r i aa n d O p e r a t i o n1 2 51 3 31 3 6VAPPENDIX B.160Acclimatization Process 160APPENDIX C 182Optimum “best known” Operating Condition 182APPENDIX D 264Maximum Loading Capacity and Recovery Process 264viLIST OF TABLESTable Page3.1 Comparative Characteristics of Prepared Synthetic Sludge And Actual Primaryand Secondary Sludges 314.1 Characteristics of Anaerobic Sludge Used in Seeding the System (AnaerobicSludge Digestor/Lion’s Gate Treatment Plant) 344.2 Experimental Running Conditions During the Optimum “Best known”Operating Condition, Maximum Loading Capacity and Recovery Period . . 375.1 Summary of Effects (SR and RR) /Interaction (SR*RR) Change in meanDuring Sequence 1, 2, and 3 Experiments 635.2 Summary of Average Responses Under Pseudo Steady-state of the DifferentDesigned Running Conditions (Sequence 1, 2, and 3 Experiments) 705.3 Performance of A Two-phase Anaerobic Sludge Digestion (UASB-UASB)Process 725.4 Statistical Constants and Kinetics During the Maximization and RecoveryPeriod 1105.5 Summary of Average Responses at the Optimum System Operating ConditionUnder Pseudo Steady-State Conditions 1235.6 Recommended Design Criteria/Start-up and Acclimatization/System Operationof the Two-phase UASB-UASB Process 130A1.1 Summary of Research Problems/Remedial Actions/Scope and ApproachviiM o d i f i c a t i o n s.1 4 8A 2 . 1 :S y s t e mS e e d i n ga n dL o a d i n gR a t e1 5 0A 2 . 2:F i n a l C o n s t i t u e n t so f P r i m a r ya n d S e c o n d a r y S y n t h e t i cS l u d g e sa n dC h e m i c a lA n a l y s i s o f D o gF o o d s1 5 0A 3 . 1 D e t a i l e dS i z i n go fA c i d - a n dM e t h a n e - P h a s eR e a c t o r s( U A S B - U A S B )... 1 5 1A 3 . 2: S p r e a d - s h e e tf o r S i z i n g o f t h eA c i d - a n dM e t h a n e - P h a s eR e a c t o r s( U A S B - U A S B )1 5 2A 4 . 1D e v e l o p m e n to fAS m a l l - S c a l e( 1 - L i t r e )S y n t h e t i cS l u d g eP r e p a r a t i o n... 1 5 3A 4 . 2 :D e v e l o p m e n to f AS c a l e - U p ( 3 0 - L i t r e ) S y n t h e t i cS l u d g eP r e p a r a t i o n. .. . 1 5 4A 5 . 1:M o n i t o r i n gt h eC h a r a c t e r i s t i c so fP r i m a r yS y n t h e t i cS l u d g eP r e p a r e dT h r o u g h o u tt h eE x p e r i m e n t1 5 6A 5 . 2 :M o n i t o r i n gt h e C h a r a c t e r i s t i c so f S e c o n d a r yS y n t h e t i cS l u d g eP r e p a r e dT h r o u g h o u tt h e E x p e r i m e n t1 5 8B 1 . 1:A v e r a g eS y s t e mE f f l u e n tQ u a l i t ya n d R e m o v a lE f f i c i e n c ya t P s e u d oS t e a d y -s t a t eU n d e rD i f f e r e n tA l t e r n a t i v e sD u r i n gt h eA c c l i m a t i z a t i o n. .. 1 6 1B 2 . 1R e s p o n s eD a t ao ft h e S a m p l i n gP o i n tN u m b e r e d1U n d e rD i f f e r e n tA c c l i m a t i z a t i o nA l t e r n a t i v e s1 6 4B 2 . 2R e s p o n s eD a t a o ft h eS a m p l i n gP o i n tN u m b e r e d2 U n d e rD i f f e r e n tA c c l i m a t i z a t i o nA l t e r n a t i v e s1 6 6B 2 . 3:R e s p o n s eD a t ao f t h eS a m p l i n gP o i n t N u m b e r e d3U n d e rD i f f e r e n tA c c l i m a t i z a t i o nA l t e r n a t i v e s1 6 8B 2 . 4 :R e s p o n s eD a t ao f t h eS a m p l i n gP o i n t N u m b e r e d4 U n d e rD i f f e r e n tv i i iA c c l i m a t i z a t i o nA l t e r n a t i v e s.B 2 . 5 R e s p o n s e Data o f t h eS a m p l i n gP o i n tNumberedA c c l i m a t i z a t i o nA l t e r n a t i v e sB 2 . 6:R e s p o n s e Data o f t h eS a m p l i n gP o i n t NumberedA c c l i m a t i z a t i o nA l t e r n a t i v e sB 2 . 7 :R e s p o n s e Data o f t h eS a m p l i n gP o i n t NumberedA c c l i m a t i z a t i o nA l t e r n a t i v e sB 2 . 8:R e s p o n s e Data o f t h eS a m p l i n gP o i n t NumberedA c c l i m a t i z a t i o nA l t e r n a t i v e sC 1 . 1:R e s p o n s e Data o f t h eS a m p l i n gP o i n t NumberedR u n n i n gC o n d i t i o n sD u r i n gt h eS e q u e n c e 1 ,2 , a n d3C 1 . 2: R e s p o n s e Data o f t h eS a m p l i n gP o i n t NumberedR u n n i n gC o n d i t i o n sD u r i n gt h eS e q u e n c e1 ,2 , a n d3C 1 . 3: R e s p o n s e Data o f t h eS a m p l i n gP o i n tN u m b e r e dR u n n i n gC o n d i t i o n sD u r i n gt h eS e q u e n c e1 ,2 , a n d3C 1 . 4:R e s p o n s e Data o f t h eS a m p l i n gP o i n t NumberedR u n n i n gC o n d i t i o n sD u r i n gt h eS e q u e n c e1 , 2 ,a n d3C 1 . 5:R e s p o n s e Data o f t h eS a m p l i n gP o i n t NumberedR u n n i n gC o n d i t i o n sD u r i n gt h eS e q u e n c e1 , 2 ,a n d3C 1 . 6: R e s p o n s e Data o f t h e S a m p l i n gP o i n t Numbered 6 Under D i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n gt h eS e q u e n c e1 ,2 , a n d3E x p e r i m e n tC 1 . 7: R e s p o n s e Data o f t h e S a m p l i n gP o i n t Numbered 7 Under D i f f e r e n ti x5 UnderD i f f e r e n t6 UnderD i f f e r e n t7 Under D i f f e r e n t8 Under D i f f e r e n t1 Under D i f f e r e n tE x p e r i m e n t2 Under D i f f e r e n tE x p e r i m e n t3 Under D i f f e r e n tE x p e r i m e n t4 Under D i f f e r e n tE x p e r i m e n t5Under D i f f e r e n tE x p e r i m e n t1 7 0• 1 7 21 7 41 7 6• 1 7 8•1 8 3• 1 8 8• 1 9 31 9 8• 2 0 32 0 8R u n n i n gC o n d i t i o n sD u r i n gt h e S e q u e n c e 1 , 2 , a n d3 E x p e r i m e n t2 1 3C 1 . 8:R e s p o n s e D a t ao f t h e S a m p l i n g P o i n tN u m b e r e d8 U n d e rD i f f e r e n tR u n n i n g C o n d i t i o n sD u r i n g t h eS e q u e n c e1 ,2 , a n d3 E x p e r i m e n t2 1 8C 2 . 1 C a l c u l a t i o no f t h e e f f e c t s ( S R a n dR R ) ,I n t e r a c t i o n ,P h a s em e a n s ,C h a n g ei nm e a n s , o n t h e R e s p o n s e P a r a m e t e r sd u r i n gt h eA c c l i m a t i z a t i o n( S e q u e n c e1 a n d 2 E x p e r i m e n t s )2 2 3C 3 . 1 :p H o f A - a n d M - U A S B sD u r i n g t h e S e q u e n c e2 a n d 3E x p e r i m e n t s a s w e l la st h e M a x i m i z a t i o n a n d R e c o v e r yP e r i o d2 6 0C 3 . 2 :N a O H ( 0 . 1N )A d d i t i o nD u r i n gt h e S e q u e n c e1 E x p e r i m e n t2 6 2D 1 . 1S u m m a r yo fA v e r a g eS y s t e mP e r f o r m a n c e a n dR e m o v a lE f f i c i e n c ya tP s e u d oS t e a d y - s t a t eD u r i n g t h e M a x i m i z a t i o n a n dR e c o v e r yP e r i o d2 6 4D 2 .1 : R e s p o n s eD a t ao f t h e S a m p l i n g P o i n tN u m b e r e d1 D i f f e r e n tR u n n i n gC o n d i t i o n s D u r i n g t h eM a x i m i z a t i o na n d R e c o v e r yP e r i o d2 6 6D 2 . 2 : R e s p o n s eD a t ao f t h eS a m p l i n gP o i n t N u m b e r e d2 D i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n g t h eM a x i m i z a t i o na n d R e c o v e r yP e r i o d2 6 8D 2 . 3 :R e s p o n s e D a t ao f t h e S a m p l i n gP o i n t N u m b e r e d3 D i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n g t h eM a x i m i z a t i o na n d R e c o v e r yP e r i o d2 7 0D 2 . 4: R e s p o n s eD a t ao f t h e S a m p l i n g P o i n tN u m b e r e d4D i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n g t h eM a x i m i z a t i o na n d R e c o v e r yP e r i o d2 7 2D 2 . 5: R e s p o n s eD a t ao f t h e S a m p l i n g P o i n tN u m b e r e d5 D i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n gt h e M a x i m i z a t i o na n dR e c o v e r yP e r i o d2 7 4D 2 . 6: R e s p o n s e D a t ao f t h eS a m p l i n gP o i n tN u m b e r e d6 D i f f e r e n tR u n n i n gxC o n d i t i o n sD u r i n gt h eM a x i m i z a t i o n a n dR e c o v e r yP e r i o d2 7 6D 2 . 7: R e s p o n s eD a t ao ft h eS a m p l i n g P o i n t N u m b e r e d7 D i f f e r e n t R u n n i n gC o n d i t i o n s D u r i n gt h eM a x i m i z a t i o na n d R e c o v e r yP e r i o d2 7 8D 2 . 8: R e s p o n s eD a t ao ft h eS a m p l i n gP o i n t N u m b e r e d 8 D i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n g t h eM a x i m i z a t i o n a n d R e c o v e r yP e r i o d2 8 0D 2 . 9: A v e r a g e R e s p o n s eD a t a o f t h e S a m p l i n g P o i n tN u m b e r e d 1t h r o u g h8a t P s e u d o S t e a d y - s t a t eU n d e r D i f f e r e n tR u n n i n g C o n d i t i o n s D u r i n gt h eD u r i n gt h e M a x i m i z a t i o na n dR e c o v e r yP e r i o d2 8 2D 3 . 1: C a l c u l a t i o no ft h eT h e o r e t i c a lC H4 P r o d u c t i o n2 8 7D 4 . 1:AM - U A S B sS y s t e mR e c o v e r ya tP s e u d oS t e a d y - s t a t e U n d e rD i f f e r e n tR u n n i n gC o n d i t i o n s(C H ,m3/m-d)2 8 8D 4 . 2:AM - U A S B sS y s t e mR e c o v e r ya t P s e u d oS t e a d y - s t a t eU n d e r D i f f e r e n tR u n n i n gC o n d i t i o n s(C O D( s o l . )R e m o v a lE f f i c i e n c y ,% ) 2 8 8D 5 . 1: R e s p o n s eD a t ao f G a s c o m p o s i t i o n ,P r o d u c t i o n ,L o a d i n gR a t e( A - a n dM - U A S B s )D u r i n gt h e A c c l i m a t i z a t i o nP r o c e s s2 8 9D 5 . 2 :R e s p o n s eD a t ao f G a s c o m p o s i t i o n ,P r o d u c t i o n ,L o a d i n gR a t e ( A -a n dM - U A S B s )D u r i n gS e q u e n c e1 , 2 ,a n d 3E x p e r i m e n t s2 9 1D 5 . 3:R e s p o n s eD a t a o fG a s c o m p o s i t i o n ,P r o d u c t i o n ,L o a d i n gR a t e( AU A S B )D u r i n g t h eM a x i m i z a t i o na n dR e c o v e r yP e r i o d2 9 5D 5 . 4R e s p o n s eD a t ao f G a sc o m p o s i t i o n ,P r o d u c t i o n ,L o a d i n gR a t e( MU A S B )D u r i n gt h eM a x i m i z a t i o na n dR e c o v e r yP e r i o d2 9 7x iL I S TO FF I G U R E SF i g u r ep a g e1 . 1 R e s e a r c h S t r a t e g y a n d A p p r o a c h42 . 1 P a t h w a y o fA n a e r o b i cB i o d e g r a d a t i o nt o s i m p l e c o m p o u n d s a n do r g a n i ca c i d s73 . 1 S c h e m a t i cF l o w D i a g r a mo f AT w o - p h a s eA n a e r o b i cS l u d g e D i g e s t i o n( U A S B - U A S B )P r o c e s s2 43 . 2 D e t a i l e dD i m e n s i o n so f U A S BR e a c t o r sU s e di n t h eE x p e r i m e n t2 43 . 3 P h o t o g r a p h so f AB e n c hS c a l e T w o - p h a s eA n a e r o b i cS l u d g e D i g e s t i o n( U A S B - U A S B )P r o c e s s2 53 . 4 C h a r a c t e r i s t i c so fP r i m a r yS y n t h e t i cS l u d g e3 03 . 5 C h a r a c t e r i s t i c so fS e c o n d a r yS y n t h e t i c3 03 . 6C h a r a c t e r i s t i c so fP r i m a r yS y n t h e t i cS l u d g eM o n i t o r e dT h r o u g h o u tt h eE x p e r i m e n t a lP r o g r a m3 23 . 7 C h a r a c t e r i s t i c so f S e c o n d a r yS y n t h e t i cS l u d g eM o n i t o r e dT h r o u g h o u tt h eE x p e r i m e n t a lP r o g r a m3 24 . 1A S c h e m a t i cF l o wD i a g r a mo f E x p e r i m e n t a lD e s i g n s3 64 . 2S a m p l i n gP r o g r a m :R e s p o n s eP a r a m e t e r s ,S a m p l i n gP o i n t , a n dF r e q u e n c y ,P r e s e r v a t i o na n dS t o r a g e3 85 . 1A n A c c l i m a t i z a t i o nW a s h o u tP h e n o m e n o n5 25 . 2S y s t e m R e m o v a lE f f i c i e n c yD u r i n gA c c l i m a t i z a t i o n5 2x i i5.3 VFA Removal Efficiency of the M-UASB 545.4 Effluent VFAs of the M-UASB 545.5 Surface Responses of Sequence 1 Experiment 655.6 NaOH (0.1 N) Addition During the Sequence 1 Experiment 675.7 System Responses and Performance of Sequence 1 Experiment 685.8 COD (soluble) Profiles Along the Reactor Height Under Different RunningConditions 765.9 Total VFA Profiles Along the Reactor Height Under Different RunningConditions 775.10 MLVSS Profiles Along the Reactor Height Under Different RunningConditions 785.11 A M-UASB Step-loading and Removal Efficiency During the SystemMaximization 865.12 Aciddogenic Phase of Glucose Formation under Low and High H2 PartialPressure to form Acetic Acids, Propionic Acids, H, Gas, and CO2 875.13 A M-UASB System Effluent Qualities During the System Maximization 885.14 A M-UASB Nutrients and MLVSS During the System Maximization 895.15 System Optimum Operating Region and Maximum Capacity 925.16 A M-UASB Step-loading and Removal Efficiency During the SystemRecovery 965.17 A M-UASB System Recovery Process 975.18 A M-UASB Nutrients and MLVSS During the System Recovery 98xiii5 . 1 9A M - U A S BS y s t e mR e c o v e r ya tP s e u d oS t e a d y - s t a t eC O D ( s o l u b l e )r e m o v a le f f i c i e n c y1 0 15 . 2 0AM - U A S BS y s t e m R e c o v e r ya tP s e u d o S t e a d y - s t a t e( C H4 G a sP r o d u c t i o n )1 0 25 . 2 1 A P r e d i c t e dM - U A S BS y s t e mR e c o v e r yW i t h D i f f e r e n tR u n n i n gC o n d i t i o n s1 0 35 . 2 2A n E s t i m a t i o no fE x p e r i m e n t a lK i n e t i c sD u r i n g t h e M a x i m i z a t i o na n dR e c o v e r yP e r i o d1 0 85 . 2 3AP r e d i c t e dO p t i m u mO p e r a t i n gH R T D u r i n gt h e M a x i m i z a t i o na n dR e c o v e r yP e r i o d1 1 25 . 2 4A NA - U A S BS y s t e mE f f l u e n tQ u a l i t i e sD u r i n gt h eM a x i m i z a t i o na n dR e c o v e r yP e r i o d1 1 75 . 2 5C o m p a r i s o no fT o t a lV F AA l o n gt h eH e i g h to fM - U A S B D u r i n gt h eA c c l i m a t i z a t i o n1 2 75 . 2 6C O D ( s o l . )P r o f i l eo faT w o - p h a s eU A S B - U A S BP r o c e s sD u r i n gM a x i m i z a t i o na n dR e c o v e r yP e r i o d1 2 95 . 2 7p HV a r i a t i o no fA - U A S Ba n dM - U A S BD u r i n gt h eS e q u e n c e2 / 3E x p e r i m e n t sa n dM a x i m i z a t i o na n d R e c o v e r yP e r i o d1 3 2B 1 . 1: E f f l u e n tQ u a l i t i e so ft h eM - U A S B( C O D ,M L V S S , PO4-P, T K N I T P )U n d e rD i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n gt h eA c c l i m a t i z a t i o n1 8 0B 2 . 1: S y s t e mG a sP r o d u c t i o na n d L o a d i n gR a t eU n d e rD i f f e r e n t R u n n i n gC o n d i t i o nD u r i n gt h eA c c l i m a t i z a t i o n1 8 1x i vD1.1 : An A-UASB Step-loading and Removal Efficiency (COD,P04-P) UnderDifferent Running Conditions During the Maximization and RecoveryPeriod 299D2.1 : An A-UASB System Nutrients and MLVSS Under Different RunningConditions During the Maximization and Recovery Period 300xvA C K N O W L E D G E M E N T SIw i s ht ot a k e t h i s o p p o r t u n i t yt o e x p r e s sm ys i n c e r et h a n k sf o rt h em o r a l e ,e n c o u r a g e m e n t , a n du n d e r s t a n d i n gr e c e i v e df r o mm yw i f e ,L a d d aa n dm y parentst h r o u g h o u tt h ec o m p l e t i o no fm yr e s e a r c h .Ia l s o w o u l dl i k e t oe x t e n dm ya p p r e c i a t i o nt o t h e f o l l o w i n g ,w h o e n t h u s i a s t i c a l l ysupported a n d e n c o u r a g e dm ei no n ew a yo ranotherD r . D . S . M a v i n i c ,m ya d v i s o ra n d Heado ft h eE n v i r o n m e n t a l E n g i n e e r i n gG r o u p ,U . B . C . a n d D r . V .L o ,C o - a d v i s o ra n dHead o f t h e B i o - R e s o u r c eE n g i n e e r i n g ,U . B . C .f o rt h e i rc r i t i c a lt e c h n i c a la d v i c ea n d f a i t h f u ls u p p o r tt h r o u g h o u tt h ec o m p l e t i o no ft h er e s e a r c h .D r . W . K . O l d h a m ,H e a do ft h e C i v i lE n g i n e e r i n g Department a n dD r . K . H a l l ,W a s t e w a t e rR e s e a r c hC e n t r ef o r t h e i ri n v a l u a b l ec o m m e n t sa n da d v i c ed u r i n gt h epreparation o f t h e r e s e a r c hp r o p o s a la n dt h e s i s .S u s a nL i p t a k ,M a n a g e ro f t h eE n v i r o n m e n t a lE n g i n e e r i n gL a b o r a t o r y ,U . B . C . ,P a u l aP a r k i n s o na n dR o m yL of o rt h e i ru n d e r s t a n d i n g , a s s i s t a n c e ,a n dg u i d a n c eo f a l la n a l y s i si n v o l v e di nt h e r e s e a r c h .x v iG u yK i r s c h , C i v i lE n g i n e e r i n gW o r k s h o p T e c h n i c i a n ,f o r h i s s u g g e s t i o na n da s s i s t a n c ei n b u i l d i n ga n d f i x i n ga l lt h ec o m p o n e n t so ft h ee x p e r i m e n t a ls y s t e mr e a c t o r s .P a n a g i o t i s( T a k i s )E l e f s i n i o t i s ,P h . D c a n d i d a t ei nt h eE n v i r o n m e n t a lE n g i n e e r i n gG r o u p ,U . B . C .f o r h i st r u e f r i e n d s h i p ,e n c o u r a g e m e n t ,a n d t e c h n i c a l a s s i s t a n c e .F i n a l l y ,Iw o u l dl i k et os i n c e r e l yt h a n km y s p o n s o r s h i p ,C a n a d i a nI n t e r n a t i o n a lD e v e l o p m e n tA g e n c y( C I D A )a n dm ye m p l o y e r ,T h a i l a n dN a t i o n a lE n v i r o n m e n t a lB o a r d( N E B ) .W i t h o u tt h e s es p o n s o r s ,t h i sr e s e a r c hw o u l dn o th a v eb e e np o s s i b l e .x v i iL I S T O F A B B R E V I A T I O N SU A S B - U A S BAT w o - p h a s eU p f l o wA n a e r o b i cS l u d g eB l a n k e tP r o c e s sA - U A S BA c i d - p h a s eU p f l o wA n a e r o b i cS l u d g eB l a n k e tR e a c t o rM - U A S BM e t h a n e - p h a s eU p f l o w A n a e r o b i cS l u d g eB l a n k e tR e a c t o rR RI n t e r n a lR e c y c l eR a t i oS RF e e dS l u d g eR a t i oH R T / €H y d r a u l i cR e t e n t i o nT i m eS R TS o l i d s R e t e n t i o nT i m eR S MR e s p o n s eS u r f a c eM e t h o dM L G HM u l t i p l eL i n e a r R e g r e s s i o nH y p o t h e s i sI nN a t u r a ll o g a r i t h mC O DC h e m i c a lO x y g e nD e m a n dM L V S SM i x e dL i q u e u rV o l a t i l eS u s p e n d e dS o l i d sT ST o t a lS o l i d sT V ST o t a lV o l a t i l eS o l i d sT S ST o t a lS u s p e n d e dS o l i d sT V S ST o t a lV o l a t i l eS u s p e n d e dS o l i d sT PT o t a lP h o s p h o r u sx v i i iTKN Total Kjeldahl NitrogenP04-P Ortho-PhosphorusNH4-N Ammonia NitrogenVFA Volatile Fatty AcidHAc Acetic acidHPr Propionic acidHBu Butyric acidHVr Valeric acidmg/L Part per millionhrs. Hoursml vfil1i—litreLid Litre per dayOHPA Obligate Hydrogen Producing AcetogensRh Hydrolysis rateKh First-order hydrolysis constantF Effluent Particulate COD concentration, mass/vol.Fo Influent Particulate COD concentration, mass/vol.k Maximum rate of substrate utilization per unitweight of microorganisms, time1Ks Half velocity coefficient, mass/vol, equal tosubstrate concentration when BL/St = (1/2)kL Influent Substrate mass concentration, mass/vol.xixLe Effluent Substrate mass concentration, mass/vol.6S/6t Net growth rate of microorganisms, mass/vol-timea Growth yield coefficient, mass/mass6L/6t Substrate utilization rate, mass/vol-timeb Microorganisms decay coefficient, time1S Microbial mass concentration, mass/vol.V Reactor VolumeQ Flow rateRCOD System COD (sol.) removal efficiency, %System P04-P removal efficiency, %RCH4 CH4 gas production, m31-dHRTAUB Hydraulic retention time of A-UASBHRTMUASB Hydraulic retention time of M-UASBHRTSY,ICA1 Hydraulic retention time of systemxxC H A P T E R O N EI N T R O D U C T I O NL i R E S E A R C HN E E D S A N D B A C K G R O U N DM a n yw a s t e w a t e r t r e a t m e n tp r o c e s s e s ,w h e t h e rp r i m a r yo rs e c o n d a r y , y i e l dl a r g eq u a n t i t i e so fw a s t em a t e r i a l si n t h e f o r m o fa d i l u t es o l i d m i x t u r e , k n o w na s s l u d g e ; t h i ss l u d g eu s u a l l yc o n t a i n sa s i g n i f i c a n ta m o u n t o f o r g a n i cw a s t e s .T r e a t m e n ta n d d i s p o s a lo f t h i s s l u d g ei sr e c o g n i z e da s o n e o ft h e m o s tc r i t i c a la r e a so fw a t e r p o l l u t i o nc o n t r o l ,a n d a c c o u n t sf o ra l m o s t 4 0 - 5 0%o f t h et o t a l c a p i t a la n do p e r a t i n gc o s t sa ta m u n i c i p a ls e w a g et r e a t m e n t p l a n t .( U . S . E P A1 9 7 9 ;G l o y n a ,1 9 8 2 ;B e n e f i e l d ,1 9 8 0 ) .A n a e r o b i c s l u d g e s t a b i l i z a t i o ni so n eo ft h em o s ts u c c e s s f u la n d p r o m i s i n gt r e a t m e n tp r o c e s s e s ,e x h i b i t i n gs e v e r a ls i g n i f i c a n ta d v a n t a g e so v e r a e r o b i cs t a b i l i z a t i o n :r e d u c t i o no fp a t h o g e n i co r g a n i s m sa n ds l u d g ep r o d u c t i o n ,s a v i n go n a i rs u p p l y ,p r e v e n t i o no fn u i s a n c e - o d o u rc o n d i t i o n sa f t e rd i g e s t i o n ,a n d f o r m a t i o no f h i g hm e t h a n ec o n t e n ti n t h e g a sp r o d u c t i o n( P o h l a n d ,1 9 7 5 ) .W i t ha ni n c r e a s ei nw o r l d w i d ee n e r g yc o s t s d u r i n gt h el a s t2 0 y e a r s ,t h ea d v a n t a g eo fp r o d u c i n gh i g h l yr e c o v e r a b l em e t h a n e( s e r v i n ga s a na d d i t i o n a le n e r g ys o u r c e )h a s a t t r a c t e dag r e a t d e a lo f r e s e a r c he f f o r t ,m a i n l yt oi n c r e a s e t h ea b i l i t ya n d r e l i a b i l i t yo f t h i sp r o c e s s .H o w e v e r ,m a n y u n a n s w e r e dp r o b l e m ss t i l le x i s t i ns t a b i l i z i n gs e w a g e s l u d g ea n a e r o b i c a l l y ,e s p e c i a l l yu s i n gc o n v e n t i o n a l ,t w o - s t a g e ,c o m p l e t e l y - m i x e dd i g e s t e r s .T h e s ei n c l u d ep o o rs u p e r n a t a n tq u a l i t y ,w h i c hg e n e r a l l yr e q u i r e sf u r t h e rt r e a t m e n t ,a n d t h er e l a t i v e l yl o wl e v e lo fm e t h a n ep r o d u c t i o np o s s i b l eu n d e rt h i s c o n v e n t i o n a lt w o - s t a g et r e a t m e n t .T oh e l p s o l v et h e s e p r o b l e m s ,t w ob r o a da p p r o a c h e sc a nb e e m p l o y e d: ( i )2increase bacterial activity by creating optimum digester operating conditions and ensuringan adequate supply of all known essential nutrients; (ii) increase the density of bacterialpopulations in the digesters ( Callander, 1983 ). The former approach incorporates thebasic mechanism of anaerobic sludge stabilization, which is, in fact, a di-phasic process -acidogenesis and methanogenesis. Therefore, providing an optimal environmentalconditions ( adequate supply of nutrients ) for each predominant group of bacteria in thetwo-phase system is expected to enhance both the methane yield and increase theprocess performance and reliability (Pohiand and Ghosh, 1971a; Massey, 1978; Cohen,1979; and Bull, 1984). The second approach aims at maintaining or increasing thehiomass and retaining it within the digester for a longer period of time, while undergoingstabilization. This can be achieved by a careful design of the floe-based digester with anappropriate sludge recycle ratio (RR). The Upflow Anaerobic Sludge Blanket (UASB)process is one of the most promising processes of the floe-based system digesters. Withcareful design, it can retain and increase biomass within the digester, without anyadditional mixing requirements.The purpose of this research was to initiate a feasibility study for enhancing theefficiency of anaerobic sludge stabilization and increase the quality level of the finalsupernatant through development of a modified design criteria, start-up process, andoperation of a two-phase, upflow anaerobic sludge stabilization (UASB-UASB) process.1.2 RESEARCH OBJECTIVES AN]) APPROACHThe principle goals were to evaluate the feasibility, effectiveness, and suitability3of this two-phase, UASB-UASB process for anaerobic sludge stabilization. The primaryobjectives were to achieve superior supernatant quality and to maximize % methanecontent and production, through a two-phase separation (UASB-UASB) process.Secondary objectives included identifying the optimum operating conditions, examiningthe effects of influent Sludge Ratio (SR) of primary to secondary sludges and RecycleRatio (RR) of fluidized sludge from sludge blanket portion of the reactor on processperformance and gas production, and investigating the maximum acceptable loading rateand associated system recovery. Time permitting, other objectives included developinga set of system design criteria and determining effective and reliable parameters forindicating process failure and system steady state conditions.It is generally recognized that a research approach must be developed in thecontext of a particular situation. A” point-in-time statement “with a continuous flow ofinformation (data sets of response parameters) as shown in Figure 1.1, represents aspecific discrete work effort, which must be achieved prior to permitting continuance offurther work tasks. As shown in Figure 1.1, emphasis was initially placed on thepreparation of a realistic research proposal. It covered the whole range of problemidentification, rationale, research objectives and approach, experimental program, as wellas work schedule and cost estimation. After approval of the research proposal, two majortasks - synthetic sludge preparation and system design and construction, were carried outsimultaneously; this was followed by system seeding and acclimatization requiring at least40-60 days to reach steady-state conditions. The sampling program and responseparameters were undertaken as shown in Figure 4.2. Along with each sequence of the•..0..oKJ..c:•::•::•::::: •s...o•...c-v••-••£2.11CD-‘CDCDCr)CDC)CI)-ICDCDD0-o0C)•x...:..:......:•0...•‘<•gN.0...cD..:....:...D:::CD0•.•..Cd)-G12:::•::m::::::•175experimental run, data analysis and results interpretation were made, using a spreadsheetsoftware program (Symphony Version 1.2), Response Surface Method (RSM) and Yate’sAlgorithm Method. The best known optimum operating condition that generated themaximum % methane content and production, with superior supernatant quality, wasthen identified ; whereas, system maximum loading capacity and the recovery processwere carried out afterward. Finally, the feasibility and effectiveness of this two-phaseUASB-UASB process, to stabilize the sludge anaerobically, together with the difficultiesand problems faced throughout the experiment and their remedial actions ( shown inTable A1.1 of appendix A ), were conclusively evaluated and reported on. The detailsof each task are discussed in Chapter 4.6CHAPTER TWOBACKGROUND AND BRIEF LITERATURE REVIEWThe purpose of this chapter is to briefly overview and update theoretical conceptson anaerobic sludge digestion and process development. The review will be used asbackground to formulate a framework for further investigation and the experimentalprogram. In case of any particular references that are closely related to the result of theresearch, they will be discussed separately in the main text of Chapter 5 - Results andDiscussion.2.1 ANAEROBIC SLUDGE DIGESTION(Biochemistry and Rate Liniitirig Step)The overall anaerobic conversion of biodegradable organic solids to the endproducts of carbon dioxide (C02) and methane (CH4) is initially believed to involve 3processes which occur simultaneously: hydrolysis of insoluble biodegradable polymers;the production of fatty acids from smaller soluble organic molecules; and CH4 generation(Stronach, 1986). But Gujer and Zehnder (1983) proposed a six-step system in theanaerobic conversion of high molecular weight degradable organics to CH4 and CO2 asshown in Figure 2.1. Two groups of bacteria, acid- and methane- producing bacteria, are,in principle, responsible for the overall anaerobic conversion of biodegradable organics.Acid-producing bacteria are responsible for converting heterogeneous substrate into fattyacids. The primary acids produced during acid fermentation are acetic, propionic, and7PROTEINS CARBOHYDRATES LIPIDS1A lB 1CAMINO ACIDS HIGHER FATTYSUGARS ALCOHOLS2 3INTERMEDIARY PRODUCTSPROPIONATE BUTYRATEETC4ACETATE HYDROGENrMETHANE61. Hydrolysis2. Fermentation3. Anaerobic (3) Oxidation4. Anaerobic Oxidation5. Decarboxylation of Acetate CH3 COO+ H2O —+ CH4 + HCO36. Hydrogen Oxidation CO+ 4H—+ CH4+ 2HzOFigure 2.1 Pathway of anaerobic biodegradationSource : After Gujer arid Zehnder, 19838butyric; however, smaller quantities of formic, valeric, iso-valeric, and caproic acids arealso frequently found (Malina, 1980). These acids are subsequently decomposed bymethane-producing bacteria, resulting in the production of methane.Approximately 85% of the CH4 results from the fermentation of acetic andpropionic acids with the remainder generated from primarily butyric and formic acids,as well as the reduction of CO2 by H2; some CH4 is generated from the fermentation oflong-chain fatty acids via anaerobic (j3) oxidation (Stronach, 1986). The pathways for theformulation of CR4 are mostly dependent on the nature of influent substances and fallinto three subgroups : lower fatty acids (C1-6,ie. formic, acetic, propionic, butyric etc.);normal or iso-alcohols (C1-5, ie. methanol, ethanol, propanol, butanol etc.); andinorganic compounds (ie. H2, CO, C02). The biochemistry of these basic reactions canbe summarized as follows:(1) Biochemical decomposition of lower fatty acids:(1.1) Acetic acid decompositionCH3OOH— CH4 + CO2 (1)(1.2) Propionic acid decompositionTwo-step requirement:4CH3C2OOH + 2H0—— 4CH3COOH + CO2 + 3CH4 (2)4CH3COOH 4CR + 4C02 (3)Overall: 4CH3C2OOH + 2H0 5CO2 + 7CR4 (4)(1.3) Butyric acid decompositionTwo-step requirement:92CH3COOH + 2H0+ C O2 - — — b 4CH3COOH + CR4.( 5 )4CH3COOH—4 C R+ 4 C 02( 6 )O v e r a l l : 2CH3COOH + 2H0 —b 3 C O+ 5 C R4( 7 )( 1 . 4 )M i c r o b i a lr e d u c t i o no f C O2 f o r m e df r o m r e d u c t i o nC O + H20—C O2 + H2( 8 )C O2+ 4 H2C H4 + 2H0( 9 )C O + 2 H — C R4+ H2O( 1 0 )4C2H5COOH+ 8H2O — b 4CH3COOH + 4 C O2 + 2 4 H( 1 1 )3 C O2 + 2 4 H— — - p3 C H4+ 6H20( 1 2 )4C2H5COOH + 2RO - — - - - * 4CH3COOH+C O2 +3 C H4( 1 3 )CH3OOH — .C H+ C O ,( 1 4 )C o n v e r s i o no f v o l a t i l ef a t t ya c i d s( V F A s )t o t h e p r o d u c t i o no f C H4 i s c o n s i d e r e dt ob ear a t e - l i m i t i n gs t e pf o r s o l u b l eo r g a n i cm a t t e r ,w h e r e a sh y d r o l y s i so fi n s o l u b l eo r g a n i c si s b e l i e v e dt ob ear a t e - l i m i t i n gs t e pf o rp a r t i c u l a t e m a t t e r( E a s t m a n ,1 9 8 1 ;C o h e n ,1 9 8 3 ;a n dP a v l o s t a t h i s ,1 9 8 6 ) .2 . 2O P E R A T I N GP A R A M E T E R SA N DR E S P O N S E SA n a e r o b i cs t a b i l i z a t i o ni sr e c o g n i z e da s as e q u e n t i a l ,d i - p h a s i cp r o c e s s :h y d r o l y s i sa n da c i d o g e n e s i s ,f o l l o w e db y m e t h a n o g e n e s i s .P h a s es e p a r a t i o ni s t h e na l o g i c a lc h o i c et o s t i m u l a t et h e g r o w t ho f t h e s et w og r o u p so f b a c t e r i a .A c i d - a n dm e t h a n e - p r o d u c i n gb a c t e r i aa r es t r i c ta n a e r o b e sa n de x t r e m e l ys e n s i t i v et oc h a n g e si nt e m p e r a t u r ea n dp H .1 0T h e s eb a c t e r i aa r e a c t i v ei n t w o temperature z o n e s : m e s o p h i l i cr a n g e( 30 - 3 5C )a n dt h e r m o p h i l i cr a n g e( 5 0 - 6 00C ) . T h eo p t i m u mp H r a n g e f o rm e t h a n e - p r o d u c i n gb a c t e r i ai s 6 . 4 - 7 . 2 ,w h e r e a si t i s 5 . 5 f o ra c i d - p r o d u c i n gb a c t e r i a .A b o v e pH 8o rb e l o w6 , t h eg r o w t ho f methane f o r m e r sf a l l s r a p i d l y .As u d d e n c h a n g ei ne n v i r o n m e n t a lc o n d i t i o n sa n d / o r a n i n t r o d u c t i o no f t o x i cs u b s t a n c e si n t ot h e s y s t e m ,m a y c a u s e t h e i m b a l a n c e dg r o w t h rate o f t h e s e t w o g r o u p so f b a c t e r i a .O n c e t h eb a l a n c ei su p s e t ,i n t e r m e d i a t eo r g a n i ca c i d sa c c u m u l a t ea n d t h ep Hd r o p s .A sar e s u l t , t h em e t h a n o g e n sa r e f u r t h e ri n h i b i t e da n d t h e p r o c e s se v e n t u a l l yf a i l s , u n l e s sc o r r e c t i v em e a s u r e s a r e t a k e n .T h i si m b a ’ a n c ec a nb ei n d i c a t e d b y v a r i o u sp a r a m e t e r s :a ni n c r e a s ei n% CO2 c o n t e n to ft h eg a sp r o d u c e da n dac o r r e s p o n d i n gd e c r e a s ei n%CH4 c o n t e n t ; a d e c r e a s ei n t h e pH a n dt o t a ld a i l yq u a n t i t yo f g a sp r o d u c e d ;a ni n c r e a s ei nt h ec o n c e n t r a t i o no fV F A s ;a no v e r a l ld e c r e a s ei nt h ee f f i c i e n c yo fw a s t es t a b i l i z a t i o n ;a n d t h er a t i oo fv o l a t i l ea c i d s / a l k a l i n i t y>0 . 5 (Graef a n d A n d r e w s ,1 9 7 4 a / b ;U S .E P A , 1 9 7 9 ) .T o x i cm a t e r i a l sa n dother m a t t e r sc a na l s ou p s e t t h es y s t e m ; t h e s ei n c l u d eo x y g e n ,v o l a t i l ea c i d s( 2 , 0 0 0m g / L ) ,t o t a l NH3-N( 1 , 5 0 0 - 3 , 0 0 0m g / La tp H7 . 4 - 7 . 6o r> 3 , 0 0 0m g / La t a n y pH v a l u e s ) ,a n ds o l u b l em e t a l se g .3 m g / LC r , 2m g / LN i ,1 m g / LZ n ,a n d0 . 5m g / LC u .H o w e v e r ,i fs u f f i c i e n tt i m ei sa v a i l a b l e ,m e t h a n e - p r o d u c i n gb a c t e r i ac a na c c l i m a t i z et ot h et o x i cm a t e r i a l s( S t r o n a c h ,1 9 8 6 ;M a l i n a ,1 9 8 0 ;C a p r i ,1 9 7 5 ;Z i e k e f o o s e ,1 9 7 6 ;K u j e l m a n ,1 9 8 1 ;G r a e f ,1 9 7 4 ;C o r t i n o v i s ,1 9 8 4 ;U S .E P A ,1 9 7 9 ;C h i u - y u e ,1 9 8 6 ) .I n at y p i c a la n a e r o b i cs l u d g ed i g e s t e r ,a p p r o x i m a t e l y7 2%o ft h em e t h a n ep r o d u c e de v o l v e st h r o u g ha c e t a t es p l i t t i n g ,a n dt h e remainder c o m e s f r o m t h er e d u c t i o no f C O ,w i t h H2 ( J e r i sa n dM c C a r t y ,1 9 6 5 ) .H y d r o g e ni s t h e na n important i n t e r m e d i a t e11in methanogenesis and a build up of hydrogen may alter the electron flow duringfermentation of carbohydrates and other polymers. Accumulation of hydrogen furtherinhibits other important intermediates being formed during anaerobic sludge digestion,such as propionate and butyrate (Scheifinger and Wolin, 1972; Chung, 1976; Kasper andWuhrmann, 1978). Therefore, Mosey, (1983a) has suggested that hydrogen gas might bea simpler and more effective prime indicator for monitoring the anaerobic digestionprocess. However, Hickey, (1987) concluded that there appeared to be some limitationson the potential of using hydrogen as a prime indicator of process upset, resulting fromthe application of organic toxicants. He found that severe inhibition of methaneproduction occurred at high organic loading rates, resulting in an accumulation ofhydrogen and VFA’s; however, at lower loading rates, inhibition was less severe andhydrogen accumulation was slightly above controls. He finally recommended monitoringhydrogen, in consert with other conventional process indicators, would provide aneffective indication of process upset due to toxic shocks.2.3 ANAEROBIC PROCESS DEVELOPMENT(Stability/Performance/Kinetics)Anaerobic process development has recently advanced in two directions:improvement of the gas yield and satisfactory substrate removal efficiency, while, at thesame time, minimizing the system capital and operating costs. A thorough investigationof the best “system operating condition” is necessary to achieve the goals of processdevelopment.1 2A r a p i de s c a l a t i o ne n e r g y s h o r t a g e sa n d h e i g h t e n e de n v i r o n m e n t a l a w a r e n e s sh a v ei n c r e a s e dt h e p r e s s u r et oi m p r o v ea n a e r o b i cd i g e s t i o np e r f o r m a n c ew h e r e a p p l i c a b l ea n df e a s i b l e .T w o b r o a da p p r o a c h e sa r eg e n e r a l l ye m p l o y e d- o n e p r o v i d i n gp r e f e r a b l yo p t i m u me n v i r o n m e n t a lc o n d i t i o n sf o re a c hg r o u p o f b a c t e r i a a n dt h e other c o n c e r n e dw i t hi n c r e a s i n gb a c t e r i ap o p u l a t i o nd e n s i t ya n dr e t a i n i n gi tw i t h i nt h ed i g e s t e r .T h ef o r m e r approach c a nb ea c h i e v e dt h r o u g ht h e u s e o f t w o - p h a s ea n a e r o b i cd i g e s t i o n , w i t ha n adequate s u p p l yo fn u t r i e n t s .T h elattero n ec a na l s ob ea c c o m p l i s h e dt h r o u g h a ni n c r e a s ei nt h es y s t e mS R Tb ym e a n so fs o l i d - l i q u i ds e p a r a t i o na n d appropriate s l u d g er e c y c l e . Either f l o c - b a s e d ( suspension) o r a n a t t a c h e d - f i x e df i l ms y s t e mc a ni n c r e a s ed i g e s t i o np e r f o r m a n c ea n dp r o v i d e sp r o m i s i n gr e s u l t s( C a l l a n d e r ,1 9 8 3 ) .T w o - p h a s ea n a e r o b i cs t a b i l i z a t i o ni sc a p a b l eo fp r o v i d i n gt h eo p t i m u m c o n d i t i o n sf o rt h eg r o w t h o fb o t ha c i d -a n dm e t h a n e -f o r m e r s ,t h e latter p r e f e r r i n gw i d e l yd i f f e r e n te n v i r o n m e n t a lc o n d i t i o n sf r o mt h e f o r m e r .T h em e r i t so f t h i s p r o c e s sa r ea ni n c r e a s ei nt h ep r o d u c t i o n rate o f CH4, m a x i m u ml o a d i n gr a t e sf o r t h em e t h a n e - p h a s er e a c t o r ,ad e c r e a s ei nr e c o v e r yt i m ea f t e rs h o c kl o a d i n g ,a n de n h a n c e m e n to f p r o c e s s e f f i c i e n c ya n dr e l i a b i l i t y( P o h i a n da n dG h o s h ,1 9 7 1 ;C o h e n ,1 9 7 9 ;M a s s e ye ta l . , 1 9 7 8 ) .A l t h o u g ha twop h a s es t a b i l i z a t i o np r o c e s ss e e m sb e s ts u i t e df o rt h e treatmento fs o l u b l e - t y p ew a s t e w a t e r sp r o d u c i n gah i g hp o t e n t i a lf o rv o l a t i l ea c i d sa c c u m u l a t i o n( P i p y ne t a l . ,1 9 7 9 ;G h o s he ta l . ,1 9 8 1 ;G h o s he ta l . ,1 9 8 3 a ) ,s u p e r i o rp e r f o r m a n c eh a sa l s ob e e nd e m o n s t r a t e df o rp a r t i c u l a t e - t y p es u b s t r a t e ss u c ha ss e w a g es l u d g ea n da g r i c u l t u r a lw a s t e s( G h o s h ,1 9 8 3 b ;K e e n a n ,1 9 7 6 ;N o r m a n n ,1 9 7 7 ;R i j k e n s ,1 9 8 1 ;Datta,1 9 8 1 ;C o l l e r a n ,1 9 8 3 ) .1 3T h e l i m i t i n g s t e p i na n a e r o b i cs t a b i l i z a t i o n o fc o m p l e xo r g a n i c m a c r o m o l e c u l e s ,s u c h a sc o n t a i n e di ns e w a g es l u d g e ,i s h y d r o l y s i s - a c i d i f i c a t i o n ,w h e r e a sf o rs t a b i l i z a t i o no f s h o r t e rc h a i ns o l u b l e o r g a n i c s w a s t e w a t e r ,i t i s m e t h a n o g e n e s i s .P h a s e - s e p a r a t e dd i g e s t i o n( h y d r o l y s i s - a c i d i f i c a t i o ni n d e p e n d e n to f m e t h a n o g e n e s i s )h a sd e m o n s t r a t e ds e v e r a lp r a c t i c a l a d v a n t a g e s :b e t t e r s t a b i l i z a t i o no f t h es l u d g e a n dag r e a t e rq u a n t i t yo fg a s , r e d u c e dd i g e s t i o nt i m e a n d r e d u c e d r e a c t o rs i z e ( G h o s h ,1 9 8 7 ;D i c h t l ,1 9 8 7 ) . P e r o t ,( 1 9 8 9 )c o n c l u d e d t h a t t w o“ o p t i m i z e d ”s t e p s h a d s e v e r a l a d v a n t a g e so v e ra s i n g l e - p h a s ed i g e s t e r :s t a r t - u p p e r i o dw a sn o t a s l o n g ( 4 5 d a y si n s t e a do f 7 5 f o r a s i n g l e - s t e pp r o c e s s ) ;h i g h e r v o l a t i l em a t t e r d e g r a d a t i o ny i e l d( 6 0 %i n s t e a do f 4 0 % ) ; a n dt h eH R Tc o u l db eh a l f o f t h a to f t h es i n g l e - s t e pp r o c e s s ,w i t h o u tr i s k i n gt h e s y s t e mg a s p r o d u c t i o na n dp e r f o r m a n c e .H e a l s o i n d i c a t e dt h a tg a s p r o d u c t i o nw a s l i n k e dp r i m a r i l yt o t h eq u a n t i t yo fb i o d e g r a d a b l eo r g a n i cm a t t e r .A n o t h e rp r o m i s i n g a p p r o a c ht oe n h a n c et h e a n a e r o b i cs l u d g e s t a b i l i z a t i o np r o c e s si s t o i n c r e a s et h e d e n s i t y o fb a c t e r i ai n t h es y s t e ma n dr e t a i n i tw i t h i n t h ed i g e s t e r ,w i t ha d e q u a t es u p p l y o fn u t r i e n t s .T h i sc a n b ed o n eb y a na p p r o p r i a t ed e s i g na n d s e l e c t i o no f ap r o p e ra n a e r o b i cs t a b i l i z a t i o np r o c e s sa n dr e c y c l e r a t i o .O n eo ft h e m a i nc r i t i c i s m so f a n a e r o b i cw a s t et r e a t m e n ti s t h ed i f f i c u l t yo f r e t a i n i n gas u f f i c i e n ta m o u n t o fa c t i v ea n a e r o b i cs l u d g eu n d e r h i g hl o a d i n gc o n d i t i o n s ,u s i n gt h ep r e s e n ta n a e r o b i ct r e a t m e n tt e c h n o l o g y .R e c e n t l y ,t h i sd i f f i c u l t yh a sb e e na d d r e s s e dt h r o u g ht h ed e v e l o p m e n to ft h eU p f l o wA n a e r o b i cS l u d g eB l a n k e t ( U A S B )p r o c e s s( H o l s o f f - P o le t a l . ,1 9 8 6 ) .U p f l o wA n a e r o b i cS l u d g eB l a n k e t( U A S B )t e c h n o l o g yi sc r e d i t e da s a n e f f e c t i v ep r o c e s si ns t a b i l i z i n gs o l u b l eo r g a n i cw a s t e , a sw e l la s p r o d u c i n gs u p e r i o rs u p e m a t a n t1 4q u a l i t y w i t h o u ta n ym i x i n g r e q u i r e m e n t s .I t a l s op r o v i d e st h e a d v a n t a g eo fd e v e l o p i n ga n d r e t a i n i n ga h i g h l y s e t t l e a b l eb i o m a s sw i t h i nt h e d i g e s t e rk n o w na s “ s l u d g e b l a n k e t ” ;t h i si s ag r a n u l a r s l u d g e m e d i a ,w i t h h i g hs e t t l e a b i l i t ya n d m e t h a n o g e n i ca c t i v i t y .T h i sb i o m a s sd e c o m p o s e st h eV F A ’ sg e n e r a t e df r o mh y d r o l y s i s - a c i d o g e n e s i sf o r t h ep r o d u c t i o no f C H4,C02, a n d s m a l l a m o u n t s o f N2,H2, e t c . T h e r i s i n g g a s e s a n d i n f l u e n tf l o w r a t e a r es i g n i f i c a n tf a c t o r si nm a i n t a i n i n gb i o m a s sg r a n u l e sa n df l o c si n m o r e - o r - l e s sf l u i d i z e ds t a t e s ,a n d t h er e s u l t i n gt u r b u l e n c ea l s o a i d s i nd e t a c h i n gg a sb u b b l e sf r o m f l o c si n t h eu p p e rp a r to ft h ed i g e s t e r .T h eb i o g a si sr e m o v e db ya t h r e e - p h a s e ,g a s / l i q u i d s / s o l i d ss e p a r a t o r( G S S - d e v i c e )a t t h et o po ft h e r e a c t o r(F i g u r e s3 . 1 - 3 . 2) ,w h o s em a i n f u n c t i o n sa r et o r e t a i nah i g h l y s e t t l e a b l eb i o m a s sw i t h i nd i g e s t e ra n d a l s ot o p r o v i d e a ne f f e c t i v es e p a r a t i o no ft h eg a sp r o d u c e dd u r i n gs t a b i l i z a t i o na s w e l la st or e t u r nt h e d i s p e r s e ds l u d g eb a c kt o t h es l u d g eb e ds i t u a t e db e l o wt h e G S S - d e v i c e( w i t ht h eh e l po f 5 0w a l lo f t h es e t t l e r ) .Ag a s - f r e ez o n ea b o v et h e c o l l e c t o ra l l o w sf o r t h es e t t l i n go ff i n e l y -d i s p e r s e ds o l i d st o t h er e a c t o r b o t t o m ,w h i l e c l a r i f i e de f f l u e n te x i t sf r o mt h et o p . A s i m p l eb a f f l ea r r a n g e m e n tc a na s s i s ti n r e t a i n i n g b i o m a s sw i t h i nt h ed i g e s t e r ,t h r o u g ht h e c r e a t i o no f a q u i e s c e n tr e g i o n ;a s s u c h ,e n t r a i n e df l o c ss e p a r a t ef r o mt h e l i q u i db e f o r ei t l e a v e st h ed i g e s t e rv i aa n u m b e ro fw e i r s .( L e t t i n g a ,1 9 8 0 ) .T o d a t e ,i ti s n o tk n o w nw h i c hf a c t o r st r i g g e rt h eg r o w t ha n dd e v e l o p m e n to fg r a n u l a rs l u d g e ,i n c l u d i n gh o wa n dw h e nt h i s b i o m a s sw i l ld e v e l o p .D o l f i n g ,( 1 9 8 6 )s u g g e s t e dt h a t a c e t o c l a s t i cM e t h a n o t h r i x - l i k eo r g a n i s m s p l a ya ni m p o r t a n tr o l ei nd e t e r m i n i n gw h i c ht y p eo f s l u d g ew o u l dd e v e l o pu n d e rm e t h a n o g e n i cc o n d i t i o n s .H ea l s os u g g e s t e dt h a te x t r a c e l l u l a rm a t e r i a lu n d o u b t e d l yp l a y e da m a j o rr o l ea sam a t r i x ,w h i c h1 5k e p tt h e c e l lt o g e t h e r .P h o s p h o r u sa n d s o d i u mm a y a l s o i n f l u e n c et h ef i l a m e n tl e n g t h o fM e t h a n o th r i x - l i k e o r g a n i s m sa s t h e y h a v e o n t h ef i l a m e n tl e n g t h o f M e t h a n o s p i r i l l u mh u n g a t e i( P a t e l , 1 9 7 9 ) . T h es l u d g e g r a n u l a t i o np r o c e s s g e n e r a l l y i n v o l v e s3 s e q u e n t i a lp r o c e s s e s :s t a r t - u p ,s a y w i t ha l o a d i n g r a t eu p t o 5 k g C O D / m3-d;t h e ng r a n u l a t i o ns l u d g ea p p e a r a n c ea n d f l o c - f o r m e d s l u d g ew a s h o u t p r o c e s s ;a n df i n a l l y c o n t i n u e d f o r m a t i o no fg r a n u l e s u n d e rav o l u m e t r i cl o a d i n gr a t e u pt o1 6k gC O D / m3-d ( L e t t i n g a , 1 9 8 6 ; W u ,1 9 8 5 ) . C u l t i v a t i o no ft h e g r a n u l a r s l u d g ec a nb e o b t a i n e dt h r o u g hac a r e f u ls e l e c t i o no fo r g a n i c s , w i t ha no p t i m u mC O D : Nr a t i o o fb e t w e e n3 0t o5 5 :1 .A d d i t i o n so f N i ,C o ,M o , a n dZ n S O4 i n t o t h e d i g e s t e ra l s oy i e l d e d p o s i t i v ee f f e c t s ( H u l s o f f - P o l ,1 9 8 6 ;W u ,1 9 8 5 ) . T h e g r a n u l a rs l u d g eb e g i n st oa p p e a r a ta C O Dl o a d i n gr a t eo fa p p r o x i m a t e l y0 . 6k g C O D / k gV S S - do r h i g h e r ,a f t e rw h i c ht h eg r a n u l a t i o np r o c e s sd e v e l o p sv e r yq u i c k l y .T h eo p t i m u mc o n d i t i o n sf o rc u l t i v a t i o nc a nb ea c h i e v e du n d e r e l e v a t e dm e s o p h i l i cc o n d i t i o n s( 3 0 - 5 0C C ) ,a p H i n e x c e s s o f6 . 5 - 7 . 2 , s u f f i c i e n tb u f f e r i n gc a p a c i t y ,a n d t h ea b s e n c eo f i n h i b i t o r ya n d t o x i c s u b s t a n c e ss u c ha s N a ,K ,a n d NH3-N; t h e s e s u b s t a n c e ss h o u l db e l o w e rt h a n 3 , 5 0 0 ,2 , 5 0 0 ,a n d 1 , 7 0 0 m g / Lr e s p e c t i v e l y( W u ,1 9 8 5 ) . W i e g a n t( 1 9 8 5 ) a l s os t r e s s e dt h a t as u p e r f i c i a lb i o g a sl o a d i n g r a t e( b i o g a sv e l o c i t y , m / h r )w a sa ni m p o r t a n tf a c t o ri nt h e g r a n u l a t i o na n ds e l e c t i o np r o c e s s .A p p r o p r i a t es t a r t - u pl o a d i n gr a t e s p l u st h e a d d i t i o no fC a+ h a v ea l s op r o v e nt ob eb e n e f i c i a lt ot h es l u d g ef l o c c u l a t i o na n dt h i c k e n i n gp r o c e s s .C a i la n d B a r f o r d( 1 9 8 6 )s t a t e dt h a t t h ep r e s e n c eo f C ai n t h er a n g eo fu p t o 1 5 0m g / L s t i m u l a t e ds l u d g eg r a n u l ef o r m a t i o na n dt h i c k e n i n g .A l s o , M a h o n e y( 1 9 8 7 ) f o u n dt h a tt h es l u d g eg r a n u l e sf o r m e di n s i d e t h er e a c t o r w i t hc a l c i u ma d d i t i o n ,s e t t l e d3 - 4 t i m e sf a s t e rt h a n t h a t w i t h o u t1 6c a l c i u m a d d i t i o n .Ah i g h r a t e o f b i o m a s sa c c u m u l a t i o nw a sa l s oe v i d e n ti n t h e c a l c i u m -p o s i t i v er e a c t o r .A no p t i m u ms t a r t - u p p r o c e s s , i n v o l v i n gf a v o u r a b l ec o n d i t i o n s f o rt h ef l o c c u l a t i o n / g r o w t h / h i g hs e t t l e a b i l i t y a n d s p e c i f i ca c t i v i t y o f t h e b i o m a s s s l u d g e ,a r e t h em a i np r e r e q u i s i t e si na c h i e v i n gs u c c e s s f u lt r e a t m e n t w i t hh i g hl o a d i n gr a t e s i n t h eU A S Bp r o c e s s .T h e l o a d i n g p o t e n t i a lo faU A S B c a nb e m a x i m i z e dt h r o u g ha c a r e f u lc o n s i d e r a t i o no f a na p p r o p r i a t ed e s i g n f o ru n i f o r mf e e d i n l e t s , a5 0 0a n g l ei n c l i n e d - w a l ls e t t l e r , w i t has u r f a c e l o a d i n g v e l o c i t yo fl e s st h a n0 . 7m / h r ,a n da n a v e r a g ef l o wt h r o u g ht h ea p e r t u r eb e t w e e ng a s c o l l e c t o r sb e l o w 2 . 0r n / h r( L e t t i n g a ,1 9 8 3 c ; S c h w a r t z ,1 9 8 2 ) .A l s or e c o m m e n d e di s p e r i o d i cw a s t i n go fs m a l la m o u n t so f s l u d g e , t om a i n t a i na c o n s t a n tl e v e lo f b i o m a s ss l u d g ew i t h i nt h e r e a c t o r( L e t t i n g a ,1 9 7 9 b ) .H o w e v e r ,c o n v e n t i o n a ls e p a r a t i o nc a nb ei n a d e q u a t ef o rt h eb u o y a n t ,f l o c c u l a n ts l u d g e .I t i ss o m e t i m e sr e p l a c e db ya l t e r n a t i v e sl i k es u r f a c e c l a r i f i c a t i o n( H a m o d a ,1 9 8 4 ) ,u l t r a f i l t r a t i o n( C h o a t e ,1 9 8 2 ) , a n d c o a g u l a n t s( C a i l ,1 9 8 6 ) .D L A I n c .( O l t h o f , 1 9 8 2 ) h a v ep l a c e dt h eb i o f i l t e r m e d i a i nt h e u p p e rz o n e o ft h e r e a c t o ro f ac o n v e n t i o n a lU A S Bp r o c e s s ,t o i n c r e a s et h e s y s t e mS R Ta n d t od a m p e nt h es h o r tc i r c u i t i n g ;t h i sp r o c e d u r eh a s a l s oi m p r o v e dg a s / s o l i d s / l i q u i ds e p a r a t i o n ,a sw e l la sp r o v i d e da s u r f a c ef o r t h ea t t a c h m e n to fb i o m a s s .T h i ss y s t e m h a sw o r k e dv e r yw e l la n d i s m a r k e t e du n d e rt h et r a d en a m e“ A n h y b r i d ” .F u r t h e r ,O l e s z k i e w i c z( 1 9 8 8 )h a s d e m o n s t r a t e dt h a t a r e a c t o r ,w i t hr a n d o mm e d i ai nt h eu p p e r 4 0%o ft h e v o l u m e ,s h o w e db e t t e rC O Dr e m o v a le f f i c i e n c ya n d g a s g e n e r a t i o n ,a s w e l la sl e s s w a s h o u to ft h ef l o c c u l a n ts l u d g et h r o u g hs h o r t c i r c u i t i n g ,t h a nt h o s er e a c t o r sw i t h m e d i ao r i e n t e dv e r t i c a l l ya n d / o rn o m e d i a .D e v e l o p m e n to fa n a e r o b i cr e a c t o r su s i n g a t t a c h e db i o m a s s ,s u c ha s t h ef l u i d i z e d1 7b e da n dt h e a n a e r o b i cf i l t e r , h a s r e s u l t e di n t h e a b i l i t y t oi n c r e a s e t h e l o a d i n gr a t e f r o m2 0 t o5 0k gC O D I m3-d a n d f r o m 1 0 t o 3 0 k g C O D / m3-d r e s p e c t i v e l y .H o w e v e r , p r o b l e m sw i t h a t t a c h e db i o m a s ss y s t e m si n c l u d e c l o g g i n ga n dh i g ho p e r a t i n gc o s t s ,d u et o e x t e r n a le n e r g yr e q u i r e m e n t s( M a a t ,1 9 8 7 ) .H ea l s of o u n d t h a t t h eU A S B o v e r c a m em a n y o ft h e s e l i m i t a t i o n sb yi n t r o d u c i n gg r a n u l a t e ds u s p e n d e db i o m a s sa n dt h eG S S - d e v i c e .T h i ss y s t e m c o u l da c h i e v e 7 5 - 9 4%r e m o v a l e f f i c i e n c y ,w i t has l u d g ec o n c e n t r a t i o no f8 - 1 3%d r y s o l i d sa tt e m p e r a t u r e sr a n g i n gf r o m2 0 - 4 00C ( e v e n i ft h e r e a c t o r l o a d i n gi s 3 0 k gC O D / m3-d o r h i g h e r ) . T h e U A S B r e a c t o r h a sb e e ns u c c e s s f u l l yc o m m e r c i a l i z e da st h eB I O P A Qw a s t e w a t e rt r e a t m e n ts y s t e m .T h ed e s i g n l o a d i n gf o rs e v e r a lB I O P A Qi n s t a l l a t i o n si s a b o u t1 0 k g COD/ni3-d, w h i l e a c t u a l c a p a c i t y l i m i t s f o r v o l u m e t r i cl o a d i n gh a v ee x c e e d e d2 0 - 3 0k gC O D / m3-d ( M a a t , 1 9 8 7 ) . C u r r e n t d e s i g np r a c t i c e sf o r U A S Br e a c t o r s ,a r ee f f e c t i v ef o rs e v e r a lt y p e s o f w a s t e w a t e r s ,r e g a r d l e s so fw h e t h e ri t i ss e w a g eo r i n d u s t r i a lw a s t e w a t e r s ( w i t he i t h e rd i l u t eo r c o n c e n t r a t e dw a s t e s ) .T h e r ea r et h r e eb a s i c c o n s i d e r a t i o n sf o rt h e d e s i g no ft h eU A S Br e a c t o r :v o l u m e t r i co r g a n i cl o a d a p p l i e d ,l i q u i dv e l o c i t yo nt h e s e t t l e rs u r f a c e ,a n dr e a c t o rh e i g h t . B a s e do n as p e c i f i cs t u d yo f at y p i c a lU A S Bp r o c e s s ,S o u z a( 1 9 8 6 )r e c o m m e n d e dt h a t m a x i m u ms a f ed e s i g nv a l u e sb ea b o u t1 5 - 2 0k g COD/m3-d, 1 . 2 - 1 . 5m / h r ,a n da h e i g h to fl e s st h a n6 . 0 m e t r e s ,r e s p e c t i v e l y .M i n i m u ma n d m a x i m u ms u p e r f i c i a lg a sr e l e a s er a t e sw e r er e c o m m e n d e dt ob e1 a n d 3 - 5m3 gas/m2-hr, r e s p e c t i v e l y .I t w a sa l s os u g g e s t e dt h a tt h ef e e di n l e t d i s t r i b u t i o na r e ab e7 - 1 0m2/inlet.L e t t i n g ae t a l .( 1 9 8 3a n d 1 9 8 6 )a t t e m p t e dt o i n c r e a s et h es u p e r f i c i a ll i q u i dv e l o c i t yu pt o 5 - 1 5m / h r ,b y i n c r e a s i n gt h e s l u d g el o a d i n gr a t e a n dr e c y c l i n gt h e e f f l u e n tb a c kt ot h es y s t e mu s i n gt h e e x p a n d e dg r a n u l a rs l u d g eb e dr e a c t o r s( E G S B ) .T h e1 8a t t e m p ta p p e a r e dt o b e f e a s i b l e .S l u d g er e c i r c u l a t i o nh e l p si n o c u l a t e t h e f r e s h s l u d g ei n s i d et h ed i g e s t e ra n d a l s oi n c r e a s et h e s y s t e m S R T .F i n a l l y ,D o l d ( 1 9 8 7 ) u s e da U A S Bt ot r e a t a p p l e j u i c ew a s t e ,a t t h e t e m p e r a t u r el e s st h a n o p t i m u m( 2 5a n d 3 0°C ) a n da m a x i m u ml o a d i n go f1 2 - 1 6 k gC O D / m3-d. H e c o n c l u d e d t h a t t h e U A S B s y s t e m w o r k e dv e r yw e l l , e v e na t al o w t e m p e r a t u r eo f2 5C a n d t h em a x i m u ml o a d i n gr a t e e m p l o y e d .A n a p p l i c a t i o no f t w o - p h a s es e p a r a t i o n ,t o t r e a tp a r t i c u l a t em a t e r i a l s( s u c h a sc r o pr e s i d u a l s ,m a n u r e , a n d m u n i c i p a lr e f u s e ) w h e r e i nh y d r o l y s i si st h e r a t e - l i m i t i n gs t e p ,i s a l s os h o w i n g p r o m i s e .Av a r i e t yo fa p p r o a c h e sh a s b e e np r o p o s e d , s u c h a su s i n gt h eU A S Ba s am o d i f i e da c i dr e a c t o r ( Z o e t e m e i j e re t a l . ,1 9 8 2 ;T h e r k e l s e n ,1 9 7 9 ) , t oa c c e l e r a t et h e r a t eo f h y d r o l y s i sa n d a c i d o g e n e s i s .H o w e v e r ,f o rs l u r r i e sl i k e s e w a g es l u d g ea n d s l a u g h t e r - h o u s ew a s t e w a t e r ,t h ea p p l i c a t i o no f p h a s es e p a r a t i o n , u s i n gU A S Bi s s t i l lq u e s t i o n a b l ei n t e r mo f r e a l b e n e f i t s ,w h e n c o m p a r e dt o as i n g l e - U A S Bp r o c e s s( L e t t i n g a ,1 9 8 3 a ) .G h o s h , ( 1 9 8 4 ) , h o w e v e r ,r e p o r t e dt h a ta t w o - p h a s eU A S Bp r o c e s sw a sv e r ye f f e c t i v ei ns t a b i l i z i n gs e w a g es l u d g e . T h em e t h a n ey i e l dw a sn e a r l y7 7 % o ft h e o r e t i c a l v a l u e sa ta nH R To f 5 . 5 a n d 5 . 9 d a y s ,i n t h e s e q u e n t i a lr e a c t o r s ;t h eo p t i m u mH R T ’ sf o r t h ea c i d -a n dm e t h a n e - p h a s er e a c t o r sw e r e0 . 9 - 1 . 5a n d4 . 0 - 5 . 0d a y s ,r e s p e c t i v e l y .S e v e r a lm o d e l sh a sb e e ni n i t i a t e d t oe x p l a i na n d p r e d i c tt h e m e c h a n i s ma n dp e r f o r m a n c eo fa n a e r o b i cd i g e s t i o n .A r b i t r a r i l y ,t h em o d e l sc a n b e c l a s s i f i e di n t o4g r o u p s :M o n o d ,s u b s t r a t ei n h i b i t i o nk i n e t i c s ,f i r s t - o r d e rk i n e t i c s ,a n dC o n t o i s - d e r i v e dk i n e t i c s .C o n c e p t u a lc o m p a r i s o n sa m o n gt h e s em o d e l si sw e l l d o c u m e n t e dw i t hM o n o dk i n e t i c sb e i n g t h em o s t p o p u l a ra n da c c e p t e da m o n gr e s e a r c h e r s ,t oe x p l a i nt h e19anaerobic digestion process (Mosey, 1983b; Ripley, 1983). For example, Monod kineticsare frequently used to explain the mechanism of anaerobic digestion of sewage sludgeand particulate materials (Pavlostathis, 1986; Massey, 1987). In addition, a mathematicalmodel for the UASB, serving as methane-phase reactor only, is well established. Theprinciple element of the model involves dynamic behaviour and distribution of the fluidpattern, anaerobic sludge in the reactor, kinetic conversion of organic wastes, andformulation of bacterial end products and CH4.The use of a mass balance for substrate,CH4, and bacterial end products in the system, is carefully made in formulating amathematical model for the UASB process (Buijis, 1981; Buijis, 1982; Heertjes,1978/1982; and Van Der Meer, 1983). An indepth review of these kinetic models isbeyond the scope of this project and the reader is referred to the literature as citedabove.From this brief literature review, it is apparent that there have been several majorstudies completed, with the basic goal of enhancing the efficiency of anaerobic sludgedigestion using the two-phase separation and/or the UASB process. However, very fewhave taken full advantage of combining these two concepts, to enhance the overalleffectiveness of anaerobic stabilization. To maximize the benefits, it appeared logical toevaluate the feasibility and effectiveness of using a two-phase UASB-UASB process, onewith an internal recycle of fluidized sludge known as sludge blanket in order to enhancethe efficiency of anaerobic sludge stabilization. The basic idea was to take advantage ofthe di-phasic phenomenon of anaerobic stabilization by using phase separation to providea preferred environment for growth stimulation of the two different groups of bacteria.2 0B y u s i n gt h eU A S Bp r o c e s sa n d i n t e r n a ls l u d g e b l a n k e tr e c y c l e c o n c e p t s , i t w a sh o p e dt oi n c r e a s e t h e c o n t a c tb e t w e e n m i c o o r g a n i s m s a n ds u b s t r a t e s a s w e l l a s t o i n c r e a s et h es y s t e mb u f f e r r i n g c a p a c i t y .T h u s t h e s y s t e mc a n r e t a i nt h e g r a n u l a rb i o m a s sw i t h i nt h ed i g e s t e r ,w i t h o u ta n y m i x i n g r e q u i r e m e n t sa n d p r o v i d eap r o m i s i n g s y s t e m p e r f o r m a n c ea n ds t a b i l i t y .T h er e s e a r c hp r o g r a m w a s i n i t i a t e da n df o r m u l a t e da l o n g t h e s el i n e s .2 1C H A P T E RT H R E ES Y S T E MS E T - U PA N DO P E R A T I O N3 . 1R A T I O N A L EA N DD E S I G NC R i T E R I AT h ep r i n c i p l e g o a l so f t h i s r e s e a r c h w e r et o e v a l u a t et h e f e a s i b i l i t y , e f f e c t i v e n e s s ,a n ds u i t a b i l i t yo f u s i n gat w o - p h a s e , U A S B - U A S Bp r o c e s st o e n h a n c e t h ee f f i c i e n c yo fa n a e r o b i c s l u d g es t a b i l i z a t i o n .T oa c h i e v et h e s eg o a l s ,as c h e m a t i cf l o w d i a g r a mo fe x p e r i m e n t a ld e s i g n sw a sd e l i n e a t e da ss h o w ni n F i g u r e 4 . 1 .T h er a t i o n a l ea n dd e s i g nc r i t e r i aw e r et h e nc o n c e p t u a l l yf o r m u l a t e d .T oe n h a n c et h e e f f i c i e n c yo fa n a e r o b i cs t a b i l i z a t i o n ,t w ob r o a da p p r o a c h e sa r eg e n e r a l l ye m p l o y e d- o n e p r o v i d i n g p r e f e r a b l yo p t i m u me n v i r o n m e n t a lc o n d i t i o n sf o re a c hg r o u po fb a c t e r i aa n dt h eo t h e rc o n c e r n e dw i t h i n c r e a s i n gb a c t e r i ap o p u l a t i o nd e n s i t ya n d r e t a i n i n gi tw i t h i nt h ed i g e s t e r .T h e f o r m e r a p p r o a c hc a n b ea c h i e v e dt h r o u g h t h e u s eo ft w o - p h a s ea n a e r o b i cd i g e s t i o n , w i t ha na d e q u a t es u p p l yo fn u t r i e n t s .At w o - p h a s eU A S B - U A S Bp r o c e s sw a ss e l e c t e dt ot r e a tas y n t h e t i cs l u d g e ,u n d e rt h es p e c i f i cc o n t r o lo ft e m p e r a t u r ea t 3 5°Ca n dp H ’ so f 5a n d7f o rt h ea c i d - p h a s e( A - U A S B )a n dm e t h a n e - p h a s e( M - U A S B )r e a c t o r sr e s p e c t i v e l y .B yc o n t r o l l i n gt h et e m p e r a t u r ea n dp H ,a s w e l la ss e p a r a t i n gt h e i re n v i r o n m e n t s ,t h ea c i d o g e n sa n dm e t h a n o g e n sw e r ee x p e c t e dt o d o m i n a t et h e m i x e dc u l t u r e so fb a c t e r i aw i t h i nt h eA - U A S Ba n dM - U A S Bu n i t s ,r e s p e c t i v e l y ;i tw a sa l s oe x p e c t e dt h a t t h e r ew o u l db ea r a p i du t i l i z a t i o no fo r g a n i cm a t t e r ,a ne f f e c t i v ep r o d u c t i o no f v o l a t i l ef a t t ya c i d s( V F A s )a n d f i n a l l ym e t h a n ep r o d u c t i o n .T o e n h a n c et h e2 2s t a b i l i z a t i o np r o c e s sa n dm e t h a n eg a s f o r m a t i o n ,n u t r i e n tr e q u i r e m e n t sm u s tb es u f f i c i e n t .V a r i a t i o ni nf e e ds l u d g er a t i o ( S R )o f p r i m a r y t os e c o n d a r ys y n t h e t i cs l u d g e s ,m e a n s as i g n i f i c a n t d i f f e r e n c ei nf e e ds l u d g ec h a r a c t e r i s t i c s( C O D / V S S ,T K N ,T P , e t c .a ss h o w n i n T a b l e3 . 1 ) . S i n c e i ti sk n o w nt h a tp r i m a r ys l u d g e c o n t a i n s m o s t l yo r g a n i c sw h i l e s e c o n d a r ys l u d g e c o n t a i n s o r g a n i c s ,n u t r i e n t s( N a n d P ) a n db a c t e r i a l c e l l s .T h i sw o u l d s t r o n g l ya f f e c t t h es y s t e mp e r f o r m a n c e sa n d m e t h a n ef o r m a t i o n .Ac a r e f u lc o m b i n a t i o no f t h e s et w o s l u d g e s ,w i t ha n o p t i m u mS R , c o u l dr e s u l t i n am a x i m i z a t i o no fC H4 g a s p r o d u c t i o na n dr e m o v a le f f i c i e n c y .T h i sw o u l d b e o fp a r t i c u l a ri n t e r e s tt ot h o s e w a s t et r e a t m e n tp l a n t st h a tp r o d u c eb o t hap r i m a r ya n ds e c o n d a r yw a s t es l u d g er e q u i r i n gf u r t h e rs t a b i l i z a t i o n .T h el a t t e ra p p r o a c hc a nb e a c c o m p l i s h e dt h r o u g ha n a p p r o p r i a t ed e s i g no f U A S Bs y s t e mc o n f i g u r a t i o nt oh e l p k e e pt h e b i o m a s si n s i d et h e r e a c t o rw i t ht h e o p t i m u lr e c y c l er a t i o( R R ) .N e wt e c h n o l o g i e sh a v e i n c o r p o r a t e dc h a n g e s ,w h i c ha l l o wS R T a n dH R Tt ob ev a r i e d i n d e p e n d e n t l y .T y p i c a l l y ,t h e s o l i d si nt h e r e a c t o re f f l u e n ta r ea l l o w e dt o s e t t l ea n dr e c y c l eb a c kt o t h er e a c t o ri n f l u e n t i no r d e rt oi n c r e a s et h e r a t i oo fS R T I H R T( C h r i s t e n s e n ,1 9 8 4 ) .S e v e r a lo t h e rf a c t o r s( f e e dc h a r a c t e r i s t i c s ,s e e ds l u d g ea n ds t a r t - u pp r o c e s s ,o p e r a t i n gc o n d i t i o n( S R ,R R ,m i x i n g ,w a s t i n g ,e t c . ) ,a n dp r o c e s sc o n f i g u r a t i o n )a r e a l s os e p a r a t e l yc o n s i d e r e dt o i m p r o v et h es y s t e mp e r f o r m a n c e si nt h i se x p e r i m e n t .I np r i n c i p l e ,U A S Bc o m p o s e so f 3m a i n c o m p o n e n t s( s l u d g eb e d , s l u d g eb l a n k e t ,a n ds e t t l e r ) .Av e r yc o n c e n t r a t e ds l u d g eb e dd e v e l o p sn e a r t h eb o t t o mo ft h e r e a c t o r .T h eb l a n k e tv a r i e sf r o m v e r yd e n s ea n d g r a n u l a rp a r t i c l e sw i t hh i g hs e t t l i n gv e l o c i t i e sn e a rt h e b o t t o m ,t o t h el i g h t e r ,m o r ed i f f u s ep a r t i c l e sa t h i g h e rl e v e lo f t h eb l a n k e t .M o s to f23the reactions occurs throughout the entire sludge bed and blanket zones. The system ismixed by hydraulic upflow and rising gas bubbles. The potential of UASB reactor, aremainly dictated by the amount of sludge that can be retained in the reactor. In theinternal settler, a quiescent zone is created to enable the sludge particle released fromthe blanket to settle rather than being washed out. Sludge separated by settling isrecirculated into the reactor and thus being retained in the system. To help increase thissludge retaining ability, internal recycling ratio (RR) of this fluidized sludge known assludge blanket back to the reactor influent can significantly enhance the systemperformance. Increasing the RR means an increase in not only the contact betweenmicroorganisms and substrates but also the system bufferring capacity, which finally canlead to the improvement of system stability and removal efficiency; however; too high anRR can break down the sludge bed and seriously damage the system performance.The success of system performance depends not only on the optimal level ofoperating conditions such as loading rate, RR, and SR, but also on the systemconfiguration. Since the UASB-UASB process is quite new, detailed microbial and kineticdata are not yet available. Conceptual and preliminary designs of this two-phaseconfiguration have to be made through a modification of existing design criteria of UASBprocess and theoretical conceptual ideas. Overall schematic diagrams of the systemconfiguration are shown in Figures 3.1 and 3.2, respectively. The detailed sizing of thesystem components is shown in Table A3.1 of Appendix A. As shown in Figure 3.1, thediameter of the settling section is double that of the sludge bed and blanket sections, and4° Cr n 1j-iEEi___A - U A S BIM - U A S BL e g e n d s :( 1 )S l u d g eb l e n d e r( 2 )M e r s( 3 )A c I d - p h a s e r e a c t o rN o t e :U q u i d f l o w( 4 )S t o r a g e t a n k( 5 )M e t h a n e - p h a s er e a c t o r( 6 )G a s t r a p ( w a t e r )G a s f i o wW e tg a sh o w m e t e r s( 8 ) P u m pc o n t r o l l e r s( 9 ) p Hc o n t r o l l e r s( 0 )T I m e rS o l i d sf l o wF i g u r e 3 . 2D e t a i l e dD i m e n s i o n s o f U A S BR e a c t o r su s e d i n t h e e x p e r i m e n tA IF - B - H-I —5 — HVN o t e :5 0d e g r e eI n c l I n e d w a l lM i x e r@A - U A S B1 . 2 7c m s . I n d l a . @I n&o u t l e tA - U A S BM - U A S_ _AF i g u r e 3 . 1S c h e m a t i c F l o w D i a g r a m o f aM o d i f i e dT w o - p h a s eA n a e r o b i cS l u d g e D i g e s t i o n( U A S B - U A S B )P r o c e s s2 4Vg a s3 5L e g e n dA - U A S B M - U A S B( e m s )( e m s )A2 02 5B1 01 5C2 0 3 0D 5 05 0E 5 05 0( A , B ) = D i a m e t e r ,c m s( C , D , E ) = H e i g h t , e m s(b)2 6h a sa5 0 0i n c l i n e d - w a l l ;i tw a sd e s i g n e dt o r e d u c e t h e u p f l o w v e l o c i t ya n d h e l ps e t t l et h es o l i d sb a c kt ot h e l o w e rp a r t s . T h i sa l s o r e d u c e ss i g n i f i c a n t l yt h e a m o u n to f supernatants o l i d s ,e s p e c i a l l yi n t h e A - U A S B r e a c t o r .T o oh i g hac o n c e n t r a t i o n ( > 5 0 0 m g / L S S ) ,c a n a f f e c tt h e M - U A S Bp e r f o r m a n c ea d v e r s e l y ( C h r i s t e n , 1 9 8 4 ). T o e n s u r e ah o m o g e n e o u sf e e ds l u d g e a n d a l s ot op r e v e n tt h e p o t e n t i a ls t a b i l i z a t i o no f t h e i n f l u e n tf e e db e f o r ee n t e r i n gt h e s y s t e m ,m i x e dp r i m a r ya n ds e c o n d a r ys l u d g e sw e r em i x e dc o n t i n u o u s l y( a t6 0 r p m )i n s i d e a 3 0 - l i t r e ,p l e x i - g l a s ss t o r a g ev e s s e l ,i n s t a l l e di n aw a l k - i ntemperature c o n t r o l l e d r o o m ,a t 4- 60C .I na d d i t i o n ,m a x i m u ms y s t e ml o a d i n gc a p a c i t y a n ds y s t e mf a i l u r ea n dr e c o v e r ya r ea l s ow o r t hi n v e s t i g a t e d .A c c i d e n t a ls h o c kl o a d (and/or o v e r l o a d i n g )a n d / o rt e m p o r a r ys y s t e mc e s s a t i o n (stoppage )m a yr e d u c e t h es y s t e mp e r f o r m a n c eo re v e nb e am a j o rc a u s eo f a c o m p l e t es y s t e mf a i l u r e . Appropriate p r i m e i n d i c a t o r so fs y s t e mf a i l u r em u s tb ei d e n t i f i e da n dq u a n t i f i e da n dt h e ns y s t e mr e c o v e r ya l t e r n a t i v e sc a n b ef o r m u l a t e d .T h e s e a d d i t i o n a l i n f o r m a t i o na n dr e s u l t sw i l lb e u s e d a sa part o f a f i n a lr e c o m m e n d a t i o no ns y s t e md e s i g na n d o p e r a t i o no f t h et w o - p h a s ea n a e r o b i cd i g e s t i o np r o c e s s( U A S B - U A S B )f o rs e w a g es l u d g e .3 . 2 EXPERIMENTAL A P P A R A T U S A N D OPERATIONA s al a b s c a l ee x p e r i m e n t ,t w oc o m p l e t e l ys e a l e du p f l o wa n a e r o b i c( A - U A S Ba n dM - U A S B )r e a c t o r sw e r ed e s i g n e dt o operate i n s i d e aw a l k - i n temperature c o n t r o l l e dr o o ma t3 5C . T h e i rh e i g h ta n dc a p a c i t yw e r e1 . 3m e t e r s ,w i t h2 0a n d2 5 l i t r e sf o rA -2 7U A S B ,a n d M - U A S B , r e s p e c t i v e l y ,a ss h o w ni n F i g u r e3 . 2 . W h e n e v e rt h e m e a s u r e dp Hw a s under t h e s e t p o i n t v a l u e so f 5 a n d 7f o r t h eA - a n d M - U A S Br e a c t o r s ,a s i g n a l w a ss e n tt o t h e c o n t r o l l e r ,w h i c h s u b s e q u e n t l yd i r e c t e dt h e d i a p h r a g mp u m pt os t a r tp u m p i n ga0 . 1 - 0 . 2NNaOH s o l u t i o ni n t ot h ed i g e s t e rt om a i n t a i nt h e p Ha t t h e s e t v a l u e s .A ss h o w ni nF i g u r e s3 . 1 a n d3 . 2 , t h ei n f l u e n ts y n t h e t i cp r i m a r ya n ds e c o n d a r ys l u d g e sw e r em i x e dw i t h i na 3 0 - l i t r es t o r a g ev e s s e ll o c a t e di n aw a l k - i n temperaturec o n t r o l l e dr o o mo f 4 - 60C ;t h e m i x t u r e w a ss u b s e q u e n t l yp u m p e dt ot h eb o t t o mo ft h eA - U A S B reactorb y ap e r i s t a l t i cp u m p .T h e l i q u i dp a s s e dt h r o u g hs l u d g eb e d ,b l a n k e t ,a n ds e t t l e r ,a n df i n a l l yl e f tt h e reactor v i a t h e w e i r .T h ee f f l u e n tf r o mt h eA - U A S Breactor w a s t h e np u m p e d t ot h eM - U A S Br e a c t o r , v i a p e r i s t a l t i cp u m p s .T h el i q u i dt h e nf o l l o w e das i m i l a r pattern t o t h a t o fA - U A S Ba n di t e v e n t u a l l y o v e r f l o w e da st h e s y s t e mf i n a le f f l u e n t .C o n c u r r e n t l y ,t h e f l u i d i z e ds l u d g eb l a n k e to fb o t h r e a c t o r s w a s r e c y c l e db a c ki n t o t h ed i g e s t e r .T h e g a sp r o d u c e df r o mb o t hr e a c t o r s w a s entrained i nag a sc a p t u r e f a c i l i t y attatched t o t h e upper p a r t o fe a c hr e a c t o r . T h eg a sw a st h e nm o n i t o r e db yt w ow e tg a s f l o wm e t e r sv i aw a t e rt r a p f l a s k s .T o e n s u r et h a t there w a s n o l e a k a g eo fg a sa n d / o rf l u i d , rubber 0 - r i n g s a n d o n e - i n c hb o l t sw e r ep l a c e da r o u n dt h ed i g e s t e rc o v e r s .A1 . 2 7c m( I D )f o o da n db e v e r a g et u b e ,w i t hs t r a i g h tc o n n e c t e r sa n dm e t a lc l a m p s ,w a su s e d ,w h e r en e c e s s a r y ,t h r o u g h o u tt h es y s t e mt op r e v e n tc l o g g i n ga n d / o rf l u i ds p i l l a g e .A l s o ,at w o - w e e ks c h e d u l eo f t i g h t e n i n gt h ec l a m p sw a si m p l e m e n t e d .A f t e rt h ec o m p l e t i o no f t h es y s t e ms e tu p ,a t e s tr u nw i t ht a pw a t e rw a sm a d et oc h e c kt h ep o s s i b i l i t yo f a n yl i q u i dl e a k i n ga n d / o rimproper o p e r a t i n ge q u i p m e n t .Ag a sl e a k i n gt e s t ,u s i n gn i t r o g e ng a sa t 2 - 3p s ia n df o a m i n ga g e n t s ,w a sa l s o2 8c a r r i e do u t s e v e r a l t i m e st oe n s u r et h a tt h e r e w a sn og a s l e a k a g e s f r o m w i t h i nt h ed i g e s t e r .3 . 3 S Y N T H E T I CS L U D G E P R E P A R A T I O NT o a v o i dp o t e n t i a lp r o b l e m so ft o x i c i t yf r o ma c t u a l w a s t e w a t e rs l u d g ea n d s u p p l yr e l i a b i l i t yf o rb o t hp r i m a r ya n d s e c o n d a r ys l u d g e s ,a s y n t h e t i cs l u d g e m i x t u r e w a su s e d .T h ei n i t i a l c o n s t i t u e n t so fs y n t h e t i cp r i m a r ys l u d g ew e r ep a r t l yb a s e do nt h o s er e p o r t e di n t h e l i t e r a t u r e( T h e r k e l s e n ,1 9 7 9 ) .T h em a i nc o n s t i t u e n t s ,b a s e do np e r c e n t a g e b yw e i g h to f t o t a ld r ys o l i d s( %b yw to f d r ys o l i d s ) ,w e r ec o m p o s e do f d o g f o o d( 7 6% ) ,s o a p ( 4% ) , c o r no i l ( 6% ) ,C a C O3( 2% ) ,a n d M g C O3( 2% ) . T h ec h e m i c a la n a l y s i so fd o gf o o d( “ N o N a m e ” - S p e c i a l - d i n n e rf o rD o g s )u s e di n t h e p r e p a r a t i o no f b o t h p r i m a r ya n ds e c o n d a r ys y n t h e t i cs l u d g e s ,i s s h o w ni nT a b l eA 2 . 2( b ) o f t h eA p p e n d i xA . T h ep r o p o r t i o no f t h e s ei n g r e d i e n t sw a sf u r t h e rm o d i f i e db y u s i n gn u m e r o u st r i a l - a n d - e r r o rt e c h n i q u e st o e n s u r et h a t t h e c h a r a c t e r i s t i c so fp r e p a r e d s y n t h e t i cs l u d g e w e r ei n t h et y p i c a l r a n g eo fa c t u a lp r i m a r ya n ds e c o n d a r ys l u d g e s ,r e s p e c t i v e l y .T h ef i n a lm o d i f i e dc o n s t i t u e n t so f p r i m a r ya n ds e c o n d a r ys y n t h e t i cs l u d g e sa r es h o w n i nT a b l e A 2 . 2( a )o fA p p e n d i xA . T h ea m o u n to f e a c hi n g r e d i e n tw a s c a l c u l a t e db a s e d o ni t s p r o p o r t i o n ,t o t a ll i q u i dv o l u m e( 3 0 a n d2 4l i t r e s) ,a n dt o t a ld r ys o l i d s( 4 a n d 2% b yw e i g h t )f o rp r i m a r ya n d s e c o n d a r ys y n t h e t i cs l u d g e s ,r e s p e c t i v e l y .T oe n s u r es u f f i c i e n tm i x i n ga n ds o l u b i l i t yo f t h ep r e p a r e dm i x t u r ea sw e l la sc o n s i s t e n c yo ft h e p r e p a r e ds l u d g ec h a r a c t e r i s t i c s ,s e v e r a ld e s i g n e dp r e p a r a t i o n2 9t e c h n i q u e s w e r ed e v e l o p e d a n dm o d i f i e d .T h es y n t h e t i c s l u d g ew a s p r e p a r e d i n s i d ea 6 0 -l i t r ep l e x i - g l a s s r e a c t o r w i t ha m e c h a n i c a l m i x e r . T h e f i n e - g r o u n d ,d o gf o o d ,t o g e t h e rw i t ha l l o t h e ri n g r e d i e n t s ,w a sd i s s o l v e d w i t ht a pw a t e rt o m a k et h e t o t a lv o l u m eo f 1 2 l i t r e sa n d w a sm i x e dc o n t i n u o u s l ya t 9 0 - 9 5r p m f o r 2 h o u r s ; i t w a st h e nl e f t o v e r n i g h ti n s i d et h e w a l k - i nt e m p e r a t u r e c o n t r o l l e dr o o m a t 4 C . A f t e rt h a t ,t h ep r e p a r e ds l u d g ew a st r a n s f e r r e dt o s e v e r a l1 . 4 - l i t r e b e a k e r sa n dw a r m e du p t o 6 5 - 7 0Ci n s i d e aw a t e rb a t hf o r 1 . 5 h o u r s ;i t w a s t h e n m i x e da t 9 0 - 9 5r p m f o r a f u r t h e r1h o u ra n d s e t t l e df o r 1 0m i n u t e s .A f t e rs e t t l i n g ,ap o r t i o no f t h e s e t t l e d s o l i d sw a s w a s t e d ,t o e n s u r et h a tt h er e m a i n i n gs o l i d s l e v e lw e r ea tt h e a s s i g n e dl e v e l o fP a n dS f o r p r i m a r ya n ds e c o n d a r ys y n t h e t i cs l u d g e s , r e s p e c t i v e l y ;a n df i n a l l y ,t h e v o l u m e s w e r em a d e u pt o3 0 a n d 2 4 l i t r e s ,f o rp r i m a r ya n ds e c o n d a r ys y n t h e t i cs l u d g e s ,r e s p e c t i v e l y .A s e r i e so fs m a l l s c a l e( 1 - l i t r e )a n ds c a l e u p( 3 0 - l i t r e ) e x p e r i m e n t a l e v a l u a t i o n sw a sc a r r i e do u t , t od e t e r m i n et h ec h a r a c t e r i s t i c so ft h e p r e p a r e ds l u d g e ,a n d t o c o m p a r ew i t ht h o s eo fa c t u a ld o m e s t i cw a s t e w a t e rs l u d g e .A ss h o w ni n F i g u r e3 . 4 a n d 3 . 5 ,a s e r i e so f r u n - a n d - c o m p a r ee x p e r i m e n t sw e r eu n d e r t a k e nf o r m o r et h a n t h r e em o n t h s ,b e f o r et h e c h a r a c t e r i s t i c so f t h es y n t h e t i cs l u d g ec o r r e s p o n d e dr e a s o n a b l yt ot h o s e o f a c t u a ls a n i t a r yw a s t es l u d g e s .D u r i n gt h e s c a l e - u pe x p e r i m e n t ,a na d d i t i o no fu r e aa n dNa2H P O4w a sn e c e s s a r yt oi n c r e a s et h ec o n c e n t r a t i o no f T K Na n d T P u pt o t h e a c t u a lr a n g ef o rs e c o n d a r ys l u d g e .N u m e r o u st r i a l - a n d - e r r o re f f o r t sw e r e s p e n to nw a s t i n go f s e t t l e ds o l i d s ,i n s u c h aw a y t h a t t h eC O D / V S Sr a t i oo fb o t hp r i m a r y a n ds e c o n d a r ys l u d g e sw a si n t h et y p i c a lr a n g ef o r a c t u a ls l u d g e .A c o m p a r a t i v es u m m a r yo f t h eb a s i cc h a r a c t e r i s t i c so fs y n t h e t i ca n dt y p i c a l“ a c t u a l ” d o m e s t i cs l u d g e si si l l u s t r a t e di n T a b l e3 . 1 .RA11O%TS%TSII%TSIII-‘—-.40-C)-‘4Co(DC)C)’00000C30(1).1IIIliiiIIIICnRATIOOR%TS%TS%TSCD%TS0-C.)(J,-.r’.)C.)O(D0000000000111111—‘IIIICoY(LJ-:rz.G) C m C) 0-U cI)8cCl) (I) C)z —Im —IC) C,) 1 C EJ G) m0.a’-1 m.Co 0)a)-•11 C/) > I a) Co 0 F rn I-U m m z0 0-1 m 0 Co//-UI10/ \-uCo/z‘z\0ICo -U,,x 0 C Co2 z,r—.‘——i—i——G) C m c)—I 0 CO 0 > cm‘ii dc,)z-na-a0 CO CO Coz H m -1 0 C,)I C C) mI’) (0(3)1 LFIC.)-UI C zI-Cl)Z0 -I0m-4ACTUALNORMALRANGE,RATIOOR%DRYDRYSOIJDS-‘-0) 0-...cna)-1.t..C00)C.).r)-‘ACTUALNORMALRANGE,RATIOOR%DRYDRYSOLIDS31Table 3 1 Comparative Characteristics of Prepared SyntheticSludge and Actual Primary and Secondary SludgesCharact. US.EPA (1979) Synthetic SludgesTypical Range # Primary SecondaryPrimary Secondary mgIL wgt % of TS mgIL wgt % of TSCOD 32900 25470TS [3—7] [1—2] 33370 3.35 19980 1.99VSS 17300 0.50 11780 0.59VS [64—93] [59—88] 30330 91.00 17600 88.14COD/VSS 11.2—1.6] 2.17 1.90 ‘ 2.16TKN [1.5—4.01 [2.4—6.7] 3.95 5.84TP [0.35—1.2] [1.3—1.6] 1.10 1.52PROTEIN [20—30] [32—41] 25.00 36.55CARBO. [17—26] 20.00 26.49TOC [17—441 41.00 33.44NOTE: # = Selected Parameters, percent by weight of dry solids (%TS)Throughout the experimental program, monitoring of key parameters of the preparedsludge was undertaken at least once a month; this monitoring showed that theconstituents and characteristics of the sludge used in the experiment were maintainedwithin 10-15 % variation. As shown in Figure 3.6 and 3.7, throughout the Sludgemonitoring period of 620 days, the characteristics of the prepared sludge were veryconsistent and fell into the typical range of both actual primary and secondary sludges.3 21 0 0 . 0 08 0 . 0 0:6 0 , 0 0 —4 0 . 0 0:2 0 . 0 0:0 . 0 0C o6 . 0 0 —0 )E4 . 0 0 —0 )-9 3 . 0 0- 6 4 . 0 0C o3 0 . 0 0— 2 0 . 0 04 . 0 00C:I1 . 2 0- - 8 85 9- 4 1— 3 2: : :I1 . 6 01 . 3 01 4 . 6 000 ,CC o3 . 5 00CC o2 . 1 7<1 0 0 . 0 08 0 . 0 06 0 . 0 04 0 . 0 0C o2 0 . 0 0 I0 . 0 004 . 0 03 . 0 0 —2 . 0 0 —1 . 0 0 —0 . 0 01 . 8 0 —. 21 . 5 0 -1 . 2 0 -0 . 9 0 —0 . 6 0 —0 . 3 0 —0 . 0 0Ta -. . ‘ . j . . 1 r t e i a . . . . . . .- — — z P f f l O . . .. Y S z z z z : Y _ —J Li iJ J J J J JiI k I- - - - - T K N— — T P‘ , E E S T K NX X T P -AC O D N S S- ç4 91 2 6 2 0 3 3 0 8 3 7 1 4 4 8 4 9 7 5 6 1 6 1 8T i m e ,d a y sF i g u r e3 . 6C h a r a c t e r i s t i c s o f P r i m a r y S y n t h e t i c S l u d g em o n i t o r e d t h r o u g h o u t t h e e x p e r i m e n t a l p r o g r a m :( a ) P r o t e i n , V S ; ( b ) T K N , T P ;( c )C O D I V S SN PNP( b )c c -C / N —— C c )\ \c c- — - - - C O D N S SC d )0C O2 . 0 0 —0 . 0 0 -1 2 . 0 0:8 . 0 0 -4 . 0 00 . 0 02 . 4 01 . 6 0 -0 . 8 0 -0 . 0 014 91 2 6 2 0 3 3 0 8 3 7 1 4 4 8 4 9 75 6 16 1 8T i m e , d a y sF i g u r e 3 . 7 C h a r a c t e r i s t i c s o f S e c o n d a r y S y n t h e t i cS l u d g em o n i t o r e d t h r o u g h o u t t h e e x p e r i m e n t a l p r o g r a m :( a ) P r o t e i n , V S ; ( b )T K N , T P ; ( c )C / N ; ( d )C O D N S S33CHAPTER FOUREXPERIMENTAL PROGRAMSThis chapter presents details of system seeding and acclimatization, followed bya series of experimental designs emphasizing the effects of influent feed sludge ratio (SR)and recycle ratio (RR) on the process performance. Maximum system loading capacityand the recovery process after a complete failure, are further investigated. An overviewof the sampling program, analytical techniques, and data I statistical analysis completethe chapter.4.1 ACCLIMATIZATION PROCESSAcclimatization is an important step in determining the success or failure of theprocess. A careful seeding and start up of the system is required.4.1.1 System Seeding and Start up LoadingIn April 1988, sludge taken from the anaerobic primary sludge digester of theLion’s Gate treatment plant (whose characteristics are shown in Table 4.1) in NorthVancouver, B.C., was used to seed both reactors with a ratio of 1:1 for seed sludge andtap water. Following the seeding, the system was fed initially at a flow rate of 2 litres/day,with a ratio of primary and secondary synthetic sludges of about 80:20 (by volume); thiswas approximately equivalent to a sludge loading rate of 0.1 gCOD/gVSS/d and a34Table 4.1 Characteristics of Anaerobic Sludge used in Seeding the System[Anaerobic sludge digester/Lion’s Gate treatment plant]Characteristics Concentrationmg/L %DsolidspH 7.2Total Alkalinity, 2740mg/L as CaCo3CODTotal COD 12490Soluble COD 3150SolidsTS 9300TVS 6900 74SS 8100VSS 6100 75NitrogensNH4—N 600NOX 0.25TKN 800 5PhosphorusP04-P 65TP 80 2.5Volatile acidsHAc 45volumetric loading rate of 1.2 gCOD/L/d, as recommended by Zeeuw, (1980).‘The calculations of seed sludge volume and starting loading rate are shown in Table A2.1of Appendix A. The loading rate was not increased unless more than 80% of the influentsoluble COD was digested. After the system stabilized, the flow rate was increased to 5L/day and loading optimization was started.3 54 . 1 . 2 S y s t e mO p e r a t i n gC o n d i t i o n sD u r i n gt h ea c c l i m a t i z a t i o np r o c e s s ,t h es y s t e mw a s o p e r a t e da t p Hv a l u e so f 5a n d7f o r t h eA - U A S B a n dM - U A S Br e a c t o r s ,r e s p e c t i v e l y .T h eA - U A S Br e a c t o r w a se q u i p p e dw i t h a m e c h a n i c a lm i x e r ,r u n n i n g f o ro n l y t h e f i r s t t w o w e e k so fa c c l i m a t i z a t i o na t t h e r a t e o f2 0 r p m , t o e n s u r es u f f i c i e n t c o n t a c tb e t w e e nb a c t e r i aa n d i n c o m i n gf e e d ;t h e s e t t l e ds l u d g eo f t h es l u d g eb e dw a s w a s t e dd a i l y a t 5 - 1 0 %o f t h e i n f l u e n tf l o wr a t e ,t om a i n t a i ns u f f i c i e n ta c t i v e v o l u m ei nt h e r e a c t o r .H o w e v e r ,n o s l u d g ew a s t i n gw a sn e c e s s a r yf o r t h eM - U A S Br e a c t o r .A l s o , t h ef l u i d i z e ds l u d g eb l a n k e te f f l u e n tw a sr e c y c l e dc o n t i n u o u s l yb a c kt ot h e s l u d g eb e d( R R )a tt h er a t eo f 4 a n d 7t i m e so ft h ei n f l u e n tf l o wr a t ef o rt h e A - U A S Ba n dM - U A S Br e a c t o r s ,r e s p e c t i v e l y .4 . 2E X P E R I M E N T A LD E S I G NT h ed e s i g na i m e dt oa c c o m p l i s ht h e r e s e a r c ho b j e c t i v e sa sm e n t i o n e de a r l i e r .T h er e l a t i o n s h i p so f e a c h c o m p o n e n ti nt h ee x p e r i m e n t a ld e s i g na r ei l l u s t r a t e d i n F i g u r e4 . 1 .T h ep r o c e s se f f e c t i v e n e s sc a nb e e v a l u a t e dm a i n l yi nt e r m so f t h ep r o c e s sp e r f o r m a n c e ,a td i f f e r e n t2 b y 2f a c t o r i a ld e s i g nr u n n i n gc o n d i t i o n s( S Ra n dR R )a n do p t i m a lo p e r a t i n gc o n d i t i o n ;w h e r e a s ,t h e p r o c e s ss u i t a b i l i t yc a na l s o b ea s c e r t a i n e dt h r o u g ht h em a x i m u ms y s t e ml o a d i n gc a p a c i t ya n dr e c o v e r yp r o c e s sa f t e r as e v e r ef a i l u r e .T h ep r o c e s sf e a s i b i l i t ya n dd e s i g nc r i t e r i aa r ef i n a l l yi n i t i a t e d .I t w a sa s s u m e dt h a tt h es y s t e mr e a c h e da p s e u d os t e a d y - s t a t ec o n d i t i o nw h e nt h eg a s p r o d u c t i o n ,% C H4 c o n t e n t ,a n de f f l u e n tC O Dr e a c h e da p p r o p r i a t e l y36steady values, with less than 10 % variation (about 2-3 system HRT).FIgute 4.iAShernatIc F!owPlagrarn:ol:ExPerImefltaI:DeSigflS:.: ISystem set-up I Synthetic sludgeL AcclimatizationL Experimental RunsOptlmai operating condition J Max. load / RecoveryEffectiveness Feasibility SuitabilityDesign Criteria rn4.2.1 Optimum “Best known” Operating ConditionsA 2 by 2 factorial design was applied to optimize the feedSR and RR within the A-UASB and M-UASB reactors. After the acclimatization processappeared to reach a pseudo steady-state at about 40-50 days, a number of differentrunning conditions was commenced (as shown in Table 4.2), to maximize the gasproduction, % CH, and also to achieve a reasonable supernatant quality.Samples were taken and analyzed twice a week for COD, TKN, TP, TS, TVSS,‘TSS, TVSS, NH4,P0 WA, and % gas components. The influent flow rate and gasproduction were recorded daily. The actual sampling program and schedules are shownin Figure 4.2. Each running condition was not changed, unless pseudo steady- state, witha minimum 2-3 system HRT and/or more than 80 % soluble COD removal efficiency (10-15 % variation in effluent soluble COD ) was achieved.For the first step in loading37Table 4.2 Experimental Running Conditions During the Optimal OperatingCondition and Maximum Loading Capacity and Recovery PeriodExperimentalRunsJSludge Feed Ratio Recycle Ratio Flaw Ratè,lJd• (SR) (RR) (FR)Phase 1: Reference Condition(Acclimatization)0 80/20 4/7 5-61 80/20 2/4 5—62 80/20 6/10 5-63 50/50 6/10 5—64 50150 214 5-6Phase 2: Best known condition5 70/30 3/6 5-66 70/30 5/8 5—67 60/40 5/8 5—68 60/40 3/6 5—69 80/20 5/8 5—6Phase 3: Additional Runs—10 80/20 4/7 5-611 90/10 5/8 5—612 90/10 3/6 5—6Maximum Loading capacity: SR = Ratio of Primary/Secondary SludgesHRT. days 9.0, 4.5, 3.0, 2.25, 1.5 RR = Ratio of Qr/QinRecovery Periods: where Qr, Qin = recycle and influent flow rateHRT, days @ 1.5, 2.25, 3.0, 4.5, 9.0 ie. 4/7, Qr = 4*Qin in the A-UASBand Qr = 7*Qin in the M-UASB‘optimization, an arbitrary reference running condition (SR8O/20 and RR4/7), used in theacclimatization process, was adopted as an initial running condition for the design of theexperimental runs. The first four running conditions followed and the responseparameters for each one was monitored and analyzed continuously, until a pseudosteady-state was obtained.Figure4.2SamplingPrograms:ResponseParameters/SamplingPointsandFrequency/PreservationandStorageResponsePreservation/SamplingPointsandFrequencyParametersStorage01123456789101.SolidsTSNo————————VSNo———————SSNo::=:=VSSNo2.OrganicsTotalCODNo**————————FilterCODNo**————————3.lnorganicsNH4-NYes**————————P04-PYes**————————TKNYes**————————TPYes**————————4.VolatileAddsHAcYes**————————HPrYes**————————lso-HBrYes**————————HBrYes**————————A-HVrYes**————————lso-HVrYes**————————HVrYes**————————HHeYes**————————5.GasCompositionNo——ProductionNo——YieldsNo——35CLegend:)SampIingPointLegends:*=OnpeamonthforPrimary/SecondarySyntheticSludges(01,02)—=Iwiceand/orthreetimesaweekGo3 9T h ea v e r a g e r e s p o n s ev a l u e s o fe a c hr u n n i n gc o n d i t i o n w e r e c a l c u l a t e di nt e r m so f m a i ne f f e c t sa n di n t e r a c t i o n o f e a c hp a r a m e t e r ,p h a s em e a n ,r e f e r e n c em e a n ,a n dc h a n g ei nm e a n r e s p o n s eb y a na p p l i c a t i o no fY a t e ’ sa l g o r i t h m .W i t ht h e s e r e s u l t s , c o u p l e dw i t h2 S E( s t a n d a r d e r r o r s )f o r e a c h i n d i v i d u a la v e r a g ea n d a n a p p l i c a t i o no f R e s p o n s eS u r f a c e M e t h o d( R S M ) ,i d e n t i f i c a t i o no ft h e “ b e s t k n o w n ”r u n n i n g c o n d i t i o n t h a tg e n e r a t e dt h em a x i m u m m e t h a n eg a sp r o d u c t i o na n dg o o ds u p e r n a t a n tq u a l i t y w a sa c h i e v e da n dt h ee f f e c t s o f S R a n dR Rw e r ea l s o c a l c u l a t e d .T h i sb e s tk n o w nc o n d i t i o nw a st h e nr e a s s i g n e da sa n a r b i t r a r yr e f e r e n c er u n n i n gc o n d i t i o nf o rt h e n e x t f o u rr u n s .4 . 2 . 2M a x i n i u mL o a d i n gR a t e a n dR e c o v e r yP e r i o d sT h e l o a d i n gr a t ei n c r e a s e dg r a d u a l l y ,s t e p - b y - s t e pu n t i lt h es y s t e m w a s o v e r l o a d e d ,c a u s i n gV F A ’ st oa c c u m u l a t ew i t h i nt h e s y s t e m .T h ep Hd r o p p e df r o m t h e d e s i r e dr a n g e ,r e s u l t i n gi na n i m b a l a n c eo f a c i d - a n dm e t h a n e - f o r m i n gp o p u l a t i o n ;t h i ss u b s e q u e n t l yl e dt oas y s t e mu p s e t .B yi n c r e a s i n gt h e l o a d i n gr a t ef r o mt h e o p t i m u mc o n d i t i o n so b t a i n e df r o m t h e p r e v i o u se x p e r i m e n t ,t h e m a x i m u ml o a d i n gr a t ew a s d e t e r m i n e d .I n a d d i t i o n ,t h e l o a d i n gr a t e w a sd e s i g n e dt o i n c r e a s eg r a d u a l l ys t e p - b y - s t e p ,w h i l et h e p Hc o n t r o l l e rw a so f f ,u n t i l t h es y s t e mc r a s h e d .T h e nt h el o a d i n gr a t ew a s d e c r e a s e dg r a d u a l l yi n o r d e rt or e c o v e rt h es y s t e ma ss h o w ni n T a b l e4 . 2 .4 . 2 . 3 S a m p l i n gP r o g r a ma n dA n a l y t i c a lT e c h n i q u e s4 . 2 . 3 . 1S a m p l i n gP r o g r a mT h es a m p l i n gp r o g r a m ,a n a l y t i c a lt e c h n i q u e s ,a n dd a t ai n t e r p r e t a t i o nw e r e4 0c a r e f u l l yd e s i g n e dt o e n s u r er e l i a b l e a n da c c u r a t er e s u l t s ,f o re v a l u a t i o no ft h e p r o c e s sp e r f o r m a n c e .A n e x t e n s i v es a m p l i n gp r o g r a mw a ss e t u p t oc h a r a c t e r i z ea n dm o n i t o rt h es y n t h e t i cs l u d g ea n ds y s t e mp e r f o r m a n c e ,a s s h o w ni n F i g u r e4 . 2 . T h ep r o p o s e dp r o g r a mw a s s t r i c t l y f o l l o w e dd u r i n gt h e a c c l i m a t i z a t i o np r o c e s sa n dt h ef i r s t f o u r r u n n i n gc o n d i t i o n s( S e q u e n c e1 ) ,h o w e v e r ;t h e s a m p l i n gp r o g r a mw a s m o d i f i e d s l i g h t l yt o“ s u i tt h ef a c t s ” o b t a i n e dd u r i n gt h ef i r s t f o u r r u n n i n gc o n d i t i o n s .T h e r e s u l t so ft h ef i r s t f o u rr u n s i n d i c a t e d thatt h e s y s t e mc o u l dr e a c hap s e u d os t e a d y - s t a t ec o n d i t i o nw i t h i n2 - 3H R T ’ sa n dt h a t there w a s v e r y l i t t l ec h a n g ei n t h er e s p o n s e parameters d u r i n g t h ef i r s tf e ww e e k so fe a c hr u n n i n g c o n d i t i o n .I tw a st h e nf e l tj u s t i f i e dt or e d u c et h es a m p l i n gf r e q u e n c yo ft h en e x t f o u rr u n n i n gc o n d i t i o n s ,t oo n c eaw e e k ,f o rt h ef i r s tf e ww e e k sa f t e rc h a n g i n g t h er u n n i n gc o n d i t i o na n dt w i c eaw e e ka f t e r w a r d ,u n t i lt h es y s t e mr e a c h e dap s e u d os t e a d y - s t a t ec o n d i t i o n (more t h a n8 0%r e m o v a le f f i c i e n c y ,2 - 3H R T s ,a n d / o r 5 - 1 0%v a r i a t i o no f t h ee f f l u e n tq u a l i t y ). H o w e v e r , m o n i t o r i n g o f t h e g a sp r o d u c t i o n ,i n f l u e n t f l o wr a t e ,a n d g a sc o n t e n tw e r e undertaken a s s c h e d u l e d ,s ot h a tt h e yc o u l db eu s e da si n d i c a t o r st op r e d i c t t h e p s e u d o s t e a d y - s t a t ec o n d i t i o n o f e a c hr u n .T h es a m p l i n gp r o g r a mf u n c t i o n e di nt w om a j o rp a r t s ; that f o r a c c l i m a t i z a t i o np e r i o d s ,a n dt h a tf o re x p e r i m e n t a lp e r i o d s .L i q u i ds a m p l e sw e r et a k e nf r o me i g h td i f f e r e n tp o i n t sa l o n gt h eh e i g h to ft h eA - U A S Ba n dM - U A S Br e a c t o r s .T w og a ss a m p l i n gr i g sw e r eu s e d .I n g e n e r a l ,al i q u i ds a m p l eo f2 5 0m lw a sc o l l e c t e d ,p r e s e r v e d ,a n da n a l y z e df o rv a r i o u sr e s p o n s e parameters t w i c e a w e e k .I n a d d i t i o n ,s y s t e mm a i n t e n a n c e ,t i g h t e n i n go fa l lc l a m p sa n dr e a c t o r ’ sc o v e r ,c h a n g i n go fa l lt u b i n gl i n e sa n dp u m ph e a d s ,a n dc h e c k i n go ft h ew a t e rl e v e la n dt u b i n go ft h eg a sf l o wm e t e r s ,e t c . ,4 1w e r ec a r r i e do u tr e g u l a r l y ,t o e n s u r et h a t p r o p e r s y s t e mo p e r a t i o n w a sm a i n t a i n e da n dt op r e v e n ta n y i n c i d e n t s o fl e a k i n ga n d / o rs p i l l a g ew h i c hm i g h t o c c u r d u r i n gt h ee x p e r i m e n t a lr u n s .4 . 2 . 3 . 2 A n a l y t i c a lT e c h n i q u e sA n a l y t i c a l m e t h o d sf o r a l lr e s p o n s ep a r a m e t e r sw e r e i n a c c o r d a n c e w i t hS t a n d a r dM e t h o d s(i6the d i t i o n , 1 9 8 5 ) , u n l e s s s p e c i f i c a l l yd e s c r i b e d s e p a r a t e l y .F o r s o l u b l es a m p l ea n a l y s i s ,s a m p l ep r e s e r v a t i o na n ds t o r a g ew e r er e q u i r e dp r i o rt o a n yf u r t h e ra n a l y s i s . As a m p l eo f 1 5 0m lc o l l e c t e df r o me a c h s a m p l i n gp o i n tw a s c e n t r i f u g e d a t2 , 5 0 0r p m . f o ra b o u t 1 5m i n u t e s ,i na nI n t e r n a t i o n a lE q u i p m e n tC o m p a n yM o d eC SC e n t r i f u g ea n dt h es u p e r n a t a n tw a s t h e nf i l t e r e dt h r o u g han o . 4 W h a t m a nf i l t e r .Af i l t r a t ea l i q u o tw a sa n a l y z e df o r s o l u b l eC O Da n d t h e r e m a i n d e r w a sp r e s e r v e da n d s t o r e d ,a ss h o w ni nF i g u r e4 . 2 , f o r f u r t h e ra n a l y s i s .A n a l y t i c a lm e t h o d sf o re a c h r e s p o n s ep a r a m e t e rc a nb es u m m a r i z e da s f o l l o w s :C h e m i c a lO x y g e n D e m a n d( C O D )S a m p l es i z e so f 0 . 1 - 0 . 5a n d1 . 0 - 2 . 0m lw e r eu s e dt o a n a l y z ef o r t o t a l a n ds o l u b l eC O Du s i n gt h e d i c h r o m a t eo x i d a t i o nr e f l u xm e t h o da so u t l i n e di nt h e S t a n d a r dM e t h o d s .S o l i d sA s a m p l eo f3 0 - 6 0m lo f e a c h s a m p l i n gp o i n tw a su s e d f o rt h ea n a l y s i so f s o l i d sc o n t e n ta s f o l l o w s :4 2T S / T V S- A s a m p l eo f 1 0 - 3 0 m lc o l l e c t e df r o mt h es a m p l i n gp o i n t n u m b e r1 , 2 , 3 , a n d6 w a s p o u r e ds e p a r a t e l yi n t o t h e k n o w nw e i g h to fe v a p o r a t i n gd i s h , w h i c h w a sh e a t e d f o r2 h o u r sa t 5 5 0°C i n s i d e t h em u f f l e f u r n a c ea n d t h e nw e i g h e d a f t e rc o o l i n g .S a m p l e sw e r et h e nd r i e d o v e r n i g h ti n aF i s h e r i s o t e m p o v e n( M o d e l 3 5 0 )a t 1 0 4°C .A f t e r c o o l i n gt h es a m p l e si n s i d e a v a c u u m d e s i c c a t o r ,t h e s a m p l e sw e r et h e nw e i g h e da n db u r n t f o ra b o u t2 h o u r s ,f o rv o l a t i l es o l i d s ,i n aL i n b e r g m u f f l e o v e na t 5 5 0°C . T h es a m p l e sw e r ef i n a l l y c o o l e d i n s i d eav a c u u m d e s i c c a t o ra n dw e i g h e d a g a i n .T S S I T V S S- A s a m p l eo f 1 0 - 2 0m l c o l l e c t e df r o mt h e s a m p l i n gp o i n t sn u m b e r e d1 - 8 ,w a s t r e a t e ds i m i l a r l yt o t h a t o fT S / T V S ,e x c e p tt h a t a 9 3 4 - A H W h a t m a ng l a s sm i c r o f i b e rw a s u s e dt of i l t e rt h e s a m p l ei n s t e a do fu s i n g t h ee v a p o r a t i n gd i s h .C a l c u l a t i o no ft h ew e i g h ta n d c o n c e n t r a t i o no f s o l i d s w a sm a d ea c c o r d i n gt o S t a n d a r dM e t h o d s .T o t a lO r g a n i cC a r b o n( T O C )T h e f i l t e r e ds a m p l e sw e r ep r e s e r v e da sd e s c r i b e di n t h eC O Ds e c t i o n ,a n da n a l y z e di na n a u t o m a t i cS h i m a d z uT o t a lO r g a n i cC a r b o n A n a l y z e r ,T O C - 5 0 0 ,u s i n gt h ec o m b u s t i o n - i n f r a r e dm e t h o d( T O C - 5 0 0I n s t r u c t i o nM a n u a l ,S h i m a d z uS c i e n t i f i cI n s t r u m e n t s ,I n c . ) .P r o t e i n sT h ec r u d ep r o t e i n c o n t e n to ft h e s a m p l e sc a nb e d e t e r m i n e df r o mt h eT K Nv a l u e4 3b y m u l t i p l y i n gi tw i t h a f a c t o ro f 6 . 2 5 .T h i s i s b a s e d o nt h e a s s u m p t i o n s t h a ta l lt h en i t r o g e no f t h e o r g a n i c m a t t e ri s d u et op r o t e i n ,a n dt h a t p r o t e i n c o n t a i n s1 6 p e r c e n tn i t r o g e no n a v e r a g e( 1 0 0 / 1 6= 6 . 2 5 ) .C a r b o h y d r a t e sT h e t o t a l s o l u b l ec a r b o h y d r a t e sw e r e d e t e r m i n e db y t h ef e r r i c y a n i d e m e t h o da so u t l i n e di n t h eH a n d b o o ko f M i c r o m e t h o d sf o r t h e B i o l o g i c a lS c i e n c e( 1 9 7 4 ) .I n o r g a n i c / A c i d sA s o l u b l es a m p l e ,a f t e rb e i n gp r e s e r v e d a n d s t o r e df o r u pt o aw e e k , w a sa n a l y z e df o r NH4-N, P04-P,T K N R ’ P ,a n dV F A sa sf o l l o w s :N H4-N - A l i q u o t so f s o l u b l es a m p l e sc o l l e c t e df r o mt h e s a m p l i n gp o i n t sn u m b e r e d1 - 8 w e r ea n a l y z e df o rN H4-N, u s i n g t h e A u t o m a t e d P h e n a t eM e t h o d( A . P . H . A . ,1 9 8 0 ) .A p p r o p r i a t ed i l u t i o n s r a n g i n gf r o m1 / 5 0- 1 / 1 0 0w e r em a d ep r i o rt od e t e r m i n i n gt h ei n t e n s i t y o ft h es a m p l ec o l o u r su s i n ga T e c h n i c o nA u t o A n a l y z e rI Ia n dt h e nc o m p a r e dw i t h t h o s eo f p r e p a r e dN H4-N s t a n d a r d s ,r a n g i n gf r o m1 . 0 - 3 . 0 m g / Li no r d e rt o e s t i m a t et h e c o n c e n t r a t i o no fN H4-N i n t h es a m p l e .P04-P - T h e a u t o m a t e da s c o r b i ca c i dr e d u c t i o nm e t h o d( T e c h n i c o nI n d u s t r i a lS y s t e m ,1 9 7 3 )w a su s e d t oa n a l y z e P04-P.I n a n a c i dm e d i u m ,a m m o n i u mm o l y b d a t ea n dp o t a s s i u ma n t i m o n y lt a r t r a t er e a c tw i t h P04-P t o f o r m a na n t i m o n y -4 4p h o s p h o m o l y b d a t ec o m p l e x ;t h i si s f u r t h e r r e d u c e d w i t ha s c o r b i ca c i d , y i e l d i n g a ni n t e n s eb l u ec o l o u r . T h e i n t e n s i t yo f t h e s a m p l e c o l o u r w a sd e t e r m i n e db y a T e c h n i c o nA u t oA n a l y z e rI I . C a l c u l a t i o no f P04-Pc o n c e n t r a t i o nw a sm a d e b y c o m p a r i n gt h e s a m p l er e s p o n s e sw i t ht h o s e o f p r e p a r e ds t a n d a r d s o f P04-P.T K N I T P - A s e r i e so fk n o w nT K N / T Ps t a n d a r d s , s o l u b l es a m p l e s , a n dd r i e ds o l i d s s a m p l e s(a f t e rb e i n gd r i e da t1 0 4 C)w e r ed i g e s t e d i n t h e T e c h n i c o nB l o c k D i g e s t e r4 0w i t hc o n c e n t r a t e d H2S04 a n d K2S04T h i s p r o c e d u r el i b e r a t e da l lb o u n do r g a n i c n i t r o g e na n d p a r t i c u l a t eT Pt oN H4-N a n d P04-P, r e s p e c t i v e l y .T h eT K N / T Pc o n c e n t r a t i o n so ft h e s a m p l e sa n ds t a n d a r d s w e r em e a s u r e dc o l o r i m e t r i c a l l y ,u s i n gt h eT e c h n i c o nA u t oA n a l y z e rI I a n d c a l c u l a t e db y c o m p a r i n gt h er e s p o n s e so f b o t hs a m p l e sa n d s t a n d a r d s .V o l a t i l ef a t t ya c i d s( V F A )S a m p l e st a k e nf r o ms a m p l i n gp o i n t sn u m b e r e d1 - 8 w e r ef i l t e r e du s i n g n o . 4W h a t m a nf i l t e r s a n df r o z e ni n s e a l e dp l a s t i c p i p e t s .A f t e rt h et i m e o f a n a l y s i s ,t h es a m p l e sw e r et h a w e da t r o o mt e m p e r a t u r ea n dd i l u t e d1 : 1 0 w i t hd i s t i l l e dw a t e r .A1 . 01t ds a m p l e ,a f t e rb e i n ga c i d i f i e db y a d r o po f1% s o l u t i o no f p h o s p h o r i ca c i dt ob r i n g t h ep H b e l o w3 . 0 ,w a s i n j e c t e di n t oac o m p u t e r - c o n t r o l l e dH e w l e t t P a c k a r d5 8 8 0 Ag a sc h r o m a t o g r a p he q u i p p e dw i t ha f l a m ei o n i z a t i o nd e t e c t o r( F I D ) ,u s i n gh e l i u ma s t h ec a r r i e rg a s .T oa c h i e v ea c c u r a t ea n dr e l i a b l e r e s u l t s ,m i c r o s y r i n g e s(H a m i l t o nM o d e l7 0i N , 1 0 L l)a n daH e w l e t tP a c k a r da u t o - s a m p l e r(M o d e l7 6 7 2 A )w e r eu s e d . T h eg l a s s4 5c o l u m n( 0 . 9 1m l o n gw i t ha 6 . 0m m( O D )a n d2 . 0 m m ( I D ) )p a c k e d w i t h 0 . 3%C a r b o w a x / 0 . 1%H3P04 o n S u p e l c o C a r b o p a kC(s u p p l i e db yS u p e l c oI n c .) ,w a sc o n d i t i o n e da c c o r d i n g t o t h ep r o c e d u r e o u t l i n e di n t h eS u p e l c oB u l l e t i n7 5 1 E ( 1 9 8 1 ) .T h e o p e r a t i n gc o n d i t i o n sf o r t h ec h r o m a t o g r a p h w e r em a i n t a i n e d a s f o l l o w s :I n j e c t i o n p o r t t e m p e r a t u r e= 1 5 0o CD e t e c t i o np o r t t e m p e r a t u r e=2 0 0°CI s o t h e r m a lo v e n t e m p e r a t u r e1 2 0°CF l o wr a t e o fc a r r i e rg a s ( h e l i u m )= 2 0m i / m mT h e r e s p o n s ep e a k so fe a c h s a m p l ew e r eq u a n t i f i e db yc o m p a r i n gw i t he x t e r n a ls t a n d a r dm e t h o d s ,u s i n gr e a g e n tg r a d e s t a n d a r d s .G a s c o n t e n tG a ss a m p l e s w e r ee x t r a c t e df r o m s a m p l i n gp o i n t s9 a n d1 0 ( S e eF i g u r e4 . 2 ) u s i n ga1 - m IH a m i l t o nS y r i n g e .T h ei n j e c t i o ns y r i n g ew a sf l u s h e d t w i c e ,b e f o r et h ei n j e c t i o ns a m p l ew a st a k e n .T h ep l u n g e r w a sd e p r e s s e dt o e x p e lt h e e x c e s sg a sp r i o r t o i n s e r t i n gt h es y r i n g en e e d l et h r o u g h t h ed i a p h r a g mo f t h es a m p l ei n j e c t i o np o r t o ft h eF i s h e rM o d e l2 9G a s P a r t i t i o n e r .T h es a m p l ew a s t h e n r a p i d l yi n j e c t e d a n da m i x t u r eo f g a s w a ss w e p tt h r o u g ht w oc h r o m a t o g r a p h i cc o l u m n s ,p a c k e d w i t hal i q u i dp h a s ei s o n as o l i ds u p p o r tk n o w na sD E H Sa n d4 2 - 6 0 m e s hM o l e c u l a rS i e v ef o rc o l u m n1a n d 2r e s p e c t i v e l y ,b y a c o n t i n u o u sf l o wo ft h eh e l i u m c a r r i e rg a s . T h eg a sc o m p o n e n t sw e r es e p a r a t e da n de l u t e d f r o mt h es y s t e m a td i f f e r e n tr e t e n t i o nt i m e s .At h e r m a lc o n d u c t i v i t yd e t e c t o rt h e ns e n s e dt h ed i f f e r e n c e si nc o n d u c t i v i t yo f t h es e p a r a t e dc o m p o n e n t s ,w h i c h46was amplified and integrated for quantification.The retention time elapsed from the point of injection to the emergence of a peakis characteristic of a particular gas. The area of a peak is also proportional to theconcentration of the gas. Calculation of the gas concentration was made by comparingthe peak areas of measurable samples and the standard.4.2.4 Data and Statistical AnalysisAll data in this research were analyzed and plotted by using an integratedsoftware program, Symphony version 1.2 and Lotus version 2.2 with an add-in program(Aliways ). Some of the graphics were imported into the Freelance software program,version 3.0, for further modifications. For the report preparation and statistical analysis,a Word Perfect 5.1 program and Systat/Sygraph programs were used.4 7C H A P T E RF I V ER E S U L T SA N D D I S C U S S I O NT h i s c h a p t e rd e a l s w i t h t w om a i ns e c t i o n s: ( i ) t h e a c c l i m a t i z a t i o nm o d e ;a n d ( i i )t h e e x p e r i m e n t a lm o d e . T h ed e v e l o p m e n to f t h ea c c l i m a t i z a t i o np r o c e s sa n d ac o m p a r i s o no fd i f f e r e n ta c c l i m a t i z a t i o na l t e r n a t i v e si sf o l l o w e d b y t h e e f f e c t sa n di n t e r a c t i o no f S l u d g eR a t i o( S R ) a n dR e c y c l eR a t i o ( R R )o n t h e r e s p o n s e sa n d p r o c e s sp e r f o r m a n c e ,m a x i m u ml o a d i n gc a p a c i t y ,a n ds y s t e m r e c o v e r yp r o c e s s .S y s t e m f e a s i b i l i t y ,d e s i g nc r i t e r i a ,a n d e f f e c t i v ea n dr e l i a b l es y s t e mi n d i c a t o r sa r e a l s od i s c u s s e d .5 . 1A C C L I M A T I Z A T I O NP R O C E S SI th a sl o n gb e e nr e c o g n i z e dt h a tt h ea c c l i m a t i z a t i o np r o c e s sh a s ag r e a ti m p a c to n t h es u c c e s so r f a i l u r eo fs y s t e m o p e r a t i o n .U n d e r s t a n d i n gt h ec o n c e p t u a ld e v e l o p m e n to ft h ep r o c e s sa n da c c l i m a t i z i n gt h es y s t e m p r o p e r l ya r ee x t r e m e l yi m p o r t a n t , i no r d e rt oa c h i e v et h e d e s i r e dl e v e lo f t h es y s t e mp e r f o r m a n c e .5 . 1 . 1D e v e l o p m e n to ft h e A c c l i m a t i z a t i o nP r o c e s sO n eo f t h em a i nd i f f i c u l t i e si n t h et r e a t m e n to fs e w a g es l u d g ea p p e a r st ob e i nt h ed e v e l o p m e n to f s u i t a b l ea n de f f i c i e n tm i x t u r e so f m i c r o b i a lc u l t u r e st ot r e a tt h i sp a r t i c u l a rt y p eo fw a s t ei nt h i st y p i c a lr e a c t o r .T oa l l e v i a t et h i sp r o b l e m ,i ti s n e c e s s a r y4 8t o u n d e r s t a n dt h e p r i n c i p l e / b e h a v i o u r / r e s p o n s eo f t h e U A S B p r o c e s su n d e r d i f f e r e n to p e r a t i n g c o n d i t i o n s .5 . 1 . 1 . 1B e h a v i o u ra n d R e s p o n s eT h e U A S Bi s as u s p e n d e d - g r o w t hb i o m a s s s y s t e mc o m p o s e do f t h r e em a i np o r t i o n s :( i ) s l u d g e b e d ; ( i i ) s l u d g eb l a n k e t ;a n d( i i i ) s e t t l e r .M o s t o ft h er e a c t i o n so c c u ri n t h e l o w e rp a r t o f t h e s y s t e m( s l u d g e b e d a n d b l a n k e t ) .I nt h et w o - p h a s eU A S B - U A S Bp r o c e s s , c o m p l e xi n f l u e n ts u b s t r a t e ss u c ha sc a r b o h y d r a t e s ,p r o t e i n s ,a n dl i p i d sa r e f i r s th y d r o l y s e da n d a c i d i f i e di n s i d et h eA - U A S Br e a c t o rb y ap r e d o m i n a n t l ya c i d o g e n i cb a c t e r i ap o p u l a t i o n ; t h i s p r o d u c e ss i m p l e c o m p o u n d ss u c h a s v o l a t i l ef a t t ya c i d s( V F A s ) .T h e s eV F A st h e np a s s t h r o u g ht h e M - U A S Br e a c t o r ,w h e r et h e ya r e s u b s e q u e n t l yc o n v e r t e dt o C H4a n d C O2 g a s e sb yp r e d o m i n a n t l ym e t h a n o g e n i cb a c t e r i a . S m a l la m o u n t so fN2g a sa n do t h e rb y - p r o d u c t sa r e a l s op r o d u c e d .U s i n gas t e p - l o a d i n ga p p r o a c h r a t h e rt h a nc o n t i n u o u s ( c o n s t a n t )l o a d i n gf o rs y s t e ms t a r t - u p ,t h es y s t e m w a sc a r e f u l l ya c c l i m a t i z e dw i t ha ni n c r e a s e i ni n f l u e n tl o a d i n gt o k e e p p a c e ,a sc l o s e a s p o s s i b l e ,w i t ha ni n c r e a s ei ns y s t e mb i o m a s s( B u l le ta l . ,1 9 8 3 ) .T h ei n f l u e n ts u b s t r a t ew a s ,t h e r e f o r e ,s t a r t e d a n dm a i n t a i n e di n i t i a l l ya t al o wl o a d i n gr a t e( s u b - c r u c i a ll e v e l )t o e n s u r eg r e a t e rc o n v e r s i o na n db i o m a s sg r o w t hr a t e st h a nw a s h o u to n e .T h e s y s t e ml o a d i n gr a t ew a sn o t i n c r e a s e du n t i lm o r et h a n 8 0%r e m o v a le f f i c i e n c yo f t h e s y s t e mi n f l u e n tC O Dh a d b e e na c h i e v e d .O v e r - o r - u n d e rh y d r a u l i ca n d / o ro r g a n i cl o a d i n gaU A S Bc a na d v e r s e l ya f f e c tt h es t a r t u pp r o c e s s .O v e r - l o a d i n gt e n d st o4 9p r o d u c ee x c e s s i v e g a s ,c a u s i n g a g a s - l i f t i nt h e r e a c t o r , f l o a t a t i o no f t h e s l u d g es o l i d s ,a n df i n a l l y ,as y s t e m w a s h o u tp r o c e s s .U n d e r - l o a d i n gr e s u l t si n t h e f o r m a t i o no fa m a s s i v ec o m p a c t e d s l u d g e ,t h u sr e d u c i n gt h ee f f i c i e n c yo f t h es y s t e ms i g n i f i c a n t l y(H u l s o f f - P o le t a l . ,1 9 8 3 ) .I n i t i a l l y ,t h es t a r t u po f n o n - a t t a c h e db i o m a s sp r o c e s s e s , l i k eU A S B ,r e l y i n gh e a v i l y o ns u s p e n d e db i o m a s sa n d a t t a c h e d m i c r o f l o r a ,a p p e a r st o i n d u c e a “ w a s h o u tp h e n o m e n o n .L a r g e q u a n t i t i e so f t h eU A S B b i o m a s s w e r ew a s h e d o u to ft h e s y s t e md u r i n gt h ef i r s tc o u p l eo f w e e k so ft h i s r e s e a r c h ,f o l l o w e db y d e v e l o p m e n to fs m a l lg r a n u l e so r p e l l e t s .T h e n , t h er e m a i n i n gb i o m a s ss h o w e d b e t t e rs e t t l e a b i l i t ya n ds e r v e da s as u r f a c em e d i u m f o ra c t i v em i c r o b i a lm a s sg r o w t h .M i n i m i z a t i o no fb i o m a s sw a s h o u ti s , t h e r e f o r e ,c r u c i a lt or e a c t o ra c t i v i t yd u r i n gt h es t a r tu pp r o c e s s .As u i t a b l e t y p eo fs e e d s l u d g e ,s e e d i n gr a t i o a n da c c l i m a t i z a t i o n ,s e e mt o b ee f f e c t i v ei nc o m p e n s a t i n gf o rt h es o l i d sw a s h o u tp h e n o m e n a .P r e c i p i t a t i o no f s a l t so f C a C O3a n d P0;3 i n s i d e t h er e a c t o ri sa l s o c r e d i t e df o ra n i n c r e a s ei n s l u d g e s e t t l e a b i l i t y ,a s t h e s es a l t sw e i g h d o w nt h ep e l l e t s ,a n di n c r e a s e t h e s e t t l i n gc a p a c i t y(K l a p w i j ke t a l . ,1 9 8 1) .C o n s i d e r i n ga l lt h e s ep o i n t sa n d b e h a v i o u r s ,a c a r e f u ls y s t e ms e e d i n ga n ds t a r t u po ft h eU A S B - U A S Bp r o c e s sw a ss e l e c t e da so u t l i n e di nC h a p t e r3 .5 . 1 . 1 . 2A c c l i m a t i z a t i o nA l t e r n a t i v e sT od e v e l o pa n e f f e c t i v es t a r tu pa n da c c l i m a t i z a t i o np r o c e s s ,t h e s y s t e mw a ss e e d e dw i t hah i g h r a t i oo fs e e d s l u d g et ot a p w a t e r( 1 : 1b y v o l u m e ) ,t oc o m p e n s a t ef o r5 0t h e s o l i d s w a s h o u tp r o b l e m .I na d d i t i o n ,t h r e ea c c l i m a t i z a t i o na l t e r n a t i v e sw e r ei n v e s t i g a t e di n d e t a i l ; s a m p l e s w e r et a k e n r e g u l a r l ya n d a n a l y z e df o r s e v e r a lp a r a m e t e r s ,a ss h o w ni nF i g u r e4 . 2 .T h e s ea l t e r n a t i v e sw e r e :( A )S e e d i n gb o t h A - a n dM - U A S B sw i t hs l u d g ef r o mt h e L i o n ’ s Gate treatment p l a n t a n a e r o b i cs l u d g ed i g e s t e r a n d u s i n ga s t e p -l o a d i n ga p p r o a c h ;( B ) S e e d i n gb o t hr e a c t o r sw i t ha c c l i m a t i z e ds y n t h e t i cs e e ds l u d g e a n du s i n ga c o n s t a n t - l o a d i n ga p p r o a c h ;( C )S e e d i n gt h e A - U A S Bw i t h a c c l i m a t i z e ds y n t h e t i cs e e d s l u d g e , b u tt h e M - U A S Bw i t h s l u d g ef r o m t h eL i o n‘ s Gate a n a e r o b i cs l u d g ed i g e s t e r ,u s i n ga s t e p - l o a d i n ga p p r o a c h .T h er e s u l t so f t h i si n v e s t i g a t i o na r es u m m a r i z e da sf o l l o w s :( a )W a s h o u tP h e n o m e n o nI ns u s p e n d e d - g r o w t hb i o m a s s s y s t e m sl i k eU A S B ,w h e r et h e treatment p o t e n t i a li sd i c t a t e db yt h ed u a l parameters o f t h e b i o m a s sq u a l i t yr e t a i n a b l ei n t h es y s t e ma n dt h es p e c i f i ca c t i v i t yo f b i o m a s s ( s u c h a s m e t h a n e p r o d u c t i o n a n d s e t t l e a b i l i t y ), a ni n o c u l a t i o no fa b o u t3 0 - 5 0%reactor v o l u m eo fa c t i v es l u d g ei sr e q u i r e d .S t a r t - u pa n da c c l i m a t i z a t i o no f U A S Br e a c t o r sr e q u i r e sa b o u t4 - 8w e e k st od e v e l o pa na c t i v em i c r o b i a lm a s ss l u d g e (Lettinga, 1 9 7 9 ; Z e e u w ,1 9 8 0 ) .S t a r t - u p ,t h e r e f o r e ,i s d e p e n d e n tu p o na ne q u i l i b r i u mb e t w e e nl o a d i n g a n d w a s h o u ta sw e l la st h e s e l e c t i o n o fas u i t a b l es e e ds l u d g e ,w a s t e w a t e rc h a r a c t e r i s t i c s ,a n d c a r e f u lm a n a g e m e n t .I n i t i a l l y ,l a r g ep o r t i o n so fb i o m a s sa r ew a s h e do u t o ft h es y s t e m ;l a t e r ,t h e m i c r o s t r u c t u r a lg r a n u l e so rp a l l e t sa r ed e v e l o p e dw i t ht h eh e l po f p r e c i p i t a t e ds a l t so f c a r b o n a t ea n dp h o s p h a t e .T h e s e5 1w e i g hd o w nt h e p e l l e t s ,i n c r e a s i n gt h e s e d i m e n t a t i o nc a p a c i t y . A s s h o w ni n F i g u r e5 . 1 ,t h e s y s t e m w i t ht h e s t e p l o a d i n gr a t e o f 0 . 1 0 - 0 . 2 1m3/m-d, d e m o n s t r a t e s t h e w a s h o u tp h e n o m e n o no f t h e M L V S S( p o i n t s 1 , 2 , a n d3 ) a t d a y 2 3 - 4 5 ,1 - 1 5 a n d 1 - 7 f o r a l t e r n a t i v e sA ,B , a n d C , r e s p e c t i v e l y .A c t i v e b i o m a s ss e t t l e sa t t h es l u d g eb l a n k e t( s a m p l i n gp o i n tn o .6 ,5 0e m sf r o mt h eb o t t o m )o ft h eM - U A S B ,t h e ns t a r t s t o b u i l d u pt o ac o n c e n t r a t i o no f 5 7 5 0 , 1 2 6 5 ,a n d 2 5 8 0m g / L o f M L V S Sf o r a l t e r n a t i v e sA , B , C ,r e s p e c t i v e l y .I ti sb e l i e v e dt h a t d e v e l o p m e n to f g r a n u l es l u d g e a n d p e l l e t i z a t i o nd o o c c u ra tt h e s l u d g eb e d .A c c i d e n t a l l y ,t h e r ew a sa c a s eo fs l u d g e s p i l l a g ed u e t oc l o g g i n gi n s i d et h er e c y c l el i n ed u r i n gt h ee x p e r i m e n t a lp r o g r a m .F o r t u n a t e l y ,t h e r e w a ss t i l l s u f f i c i e n tb i o m a s sr e m a i n i n ga tt h e b o t t o mo f t h er e a c t o r ; t h i sw a s c h a r a c t e r i z e db yv e r yh a r d a n dd e n s e p e l l e t s .A l s o ,J i n g - Q i n gY a n ( 1 9 9 1 )s t u d i e das l u d g ec o n c e n t r a t i o np r o f i l ea l o n gt h eh e i g h to fU A S Ba n di n d i c a t e d t h a tt h e r ew e r e2d i s t i n c t l a y e r so fs l u d g ec o n c e n t r a t i o np r o f i l e s .T h e s e i n c l u d e dad e n s es l u d g eb e d( f r o m0 - 3 0c m s . )w i t h1 8 - 5 8g / LV S S a n das l u d g eb l a n k e t( a b o v e3 7c m s . )w i t h2 - 1 0 g / LV S S .T h e a u t h o ra l s om e n t i o n e dt h a ts y s t e ms t a r t - u pp r o c e s sw i t ha s l u d g el o a d i n gr a t eo fl e s st h a n 0 . 2k gC O D / k gV S S - dw a s c r u c i a lf o r a s u c c e s s f u ld e v e l o p m e n to f p e l l e t i z a t i o n .A sm e n t i o n e de a r l i e r ,t h es t a r t - u ps l u d g el o a d i n gr a t ei nt h e p r e s e n tc a s e ( U A S B - U A S B ) w a sa b o u t0 . 1k gC O D / k gV S S - da n dt h e c o n c e n t r a t i o no f M L V S Sa ts l u d g eb l a n k e tl e v e l( 5 0c m s .h e i g h t )w a si n t h er a n g eo f1 3 0 0 - 5 8 0 0m g / L .S i n c es i m i l a rp a t t e r n so fs t a r t - u pp r o c e s sa n dM L V S Sc o n c e n t r a t i o nr a n g ew e r eo b s e r v e di n t h ep r e s e n ts t u d y ,i ti s b e l i e v e dt h a td e v e l o p m e n to f s l u d g ec o n c e n t r a t i o np r o f i l e( p e l l e t i z a t i o o n )d i d o c c u ri nt h e s y s t e m .I ti s q u i t ec l e a rt h a t a c i d o g e n i ca n dm e t h a n o g e n i cb a c t e r i ap l a y a ni m p o r t a n tr o l e5 2( a ) ( b ) ( C )5 I4 -E f f l u e n t M L V S S. R e a c t o r M L V S S43II I I I_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _02 04 06 002 04 06 002 04 06 0l i m e , d a y sF i g u r e5 . 1A n A c c l i m a t i z a t i o nW a s h o u tP h e n o m e n o nU n d e rd i f f e r e n t r u n n i n gc o n d f t l o n s( a , b , a n dc ) ,M e n t i o n e di n s e c t i o n5 . 1 . 1 . 2A c c l i m a t I z a t i o nA l t e r n a t i v e s4 0\ Y / ( a ) ( b ) ( C )3 0—+ c o o+S o L C O D0 4 - P2 0I I . . , —I—I II II II III02 04 06 002 04 06 00 2 04 06 0T i m e ,d a y sF i g u r e5 . 2S y s t e mR e m o v a lE f f i c i e n c yD u r i n gA c c l i m a t i z a t i o n :U n d e rd i f f e r e n tr u n n i n gc o n d i t i o n s( a , b , a n dc ) ,M e n t i o n e di ns e c t i o n5 . 1 . 1 . 2A c c l i m a t I z a t i o nA l t e r n a t i v e s53in the initial wash out phenomenon. As shown in alternative A, Figures 5.1, it tookapproximately 23 days to develop active and sufficient amounts of acidogenic andmethanogenic bacteria to dominate within A- and M-UASB reactors, respectively. As aresult, influent substrate is hydrolysed and acidified in theA-UASB, producing low to medium molecular weight VFA’s such as HVr, HBu, HPr,HAc etc.; these are further broken down to CH4,C02, and H2 by methanogenic bacteriain the M-UASB. Figures 5.3-5.4 showed a decrease of influent total VFA from 4,070 to1,120 mg/L with an HAcIHPr concentration ratio of 1:40, corresponding to an increaseof VFA removal efficiency of the M-UASB up to 71 %. The produced gas (CH4,C02,H2, and etc.) then caused a gas-lift, solids sludge floatation, and finally, a system washoutphenomenon in the M-UASB reactor at point (1) of the Figure 5.1. Conversely,alternatives B and C demonstrated the washout phenomenon immediately after day 1(points 2 and 3, respectively), and it took only a week for alternative C to start up,compared to two weeks for alternative B; however, the acclimatization process wascompleted within 4 weeks for both alternatives. Lettinga (1978) found a similar resultwhereby, when he acclimatized a UASB at 30 C with 1250 mg/L HAc and 1000 mg/LHBu, a distinct granulation appeared 5 weeks after the start-up of the process.The time reduction, compared with alternative A, may result from theeffectiveness of well acclimatized synthetic sludge seeded in A-UASBs, generatingsufficient volume of VFAS ready for methanogenesis to proceed further in the M-UASB.Comparing alternatives B and C at day 20-30 (same range of loading rate in bothalternatives as shown in Figure B2.1 of Appendix B), it is interesting to point out that5 42 0> .C . )a )C )C )0- 6 0( a )4C )IhL M11 0 06 0/( a ) ( b )( c )— I I— II—- 1 0 0- 1 4 0502 0 4 0 6 00 2 04 06 002 04 06 0T i m e , d a y sF i g u r e 5 . 3V F AR e m o v a l E f f i c i e n c yo ft h e M - U A S B :D u r i n g t h e a c c l i m a t i z a t i o n u n d e rd i f f e r e n t r u n n i n gc o n d i t i o n s ( a , b , a n d c ) ,M e n t i o n e di ns e c t i o n 5 . 1 . 1 . 2 A c c l i m a t i z a t i o nA f t e r n a t i v e s( b )I1 1 1 1 1 L I5( C )43 - J - .- C , ):I IIIIIII02 0 4 06 02 04 06 02 0 4 06 0T i m e ,d a y sF i c i u r e5 . 4 E f l u e n tV F A s o f t h eM - U A S B :D u r i n g t J T ea c c l i m a t i z a t i o nu n d e r d i f f e r e n tr u n n i n gc o n d i t i o n s ( a , b , a n d c ) ,M e n t i o n e d i n s e c t i o n5 . 1 . 1 . 2A c c l i m a t i z a t i o nA l t e r n a t i v e s5 5a l t e r n a t i v eC h a d b e t t e rp e r f o r m a n c e st h a nt h o s e o f a l t e r n a t i v eB i n t e r m so f s y s t e ma n dV F A r e m o v a l e f f i c i e n c i e sa n de f f l u e n t V F Aa ss h o w n i n F i g u r e s 5 . 2 - 5 . 4 .T h i s m a yb ec a u s e d b y am o r ed i v e r s i f i e ds t r u c t u r e o fb a c t e r i a l c o m m u n i t yd u e t o t h e s t e p - l o a d i n ga p p r o a c h( s t a r t i n gf r o ml o wl o a d i n g r a t e w i t hs e e d s l u d g ef r o m L i o n ’ s G a t ea n a e r o b i cd i g e s t e ru s e di na l t e r n a t i v eC , c o m p a r e d w i t hac o n s t a n t l o a d i n g s c h e m e( h i g h l o a d i n gr a t e ) a n d a c c l i m a t i z e ds e e ds l u d g e i na l t e r n a t i v eB .P a v o n i( 1 9 7 2 )a n dE n c i n a( 1 9 8 7 )i n d i c a t e dd u r i n gt h es t a r t - u pp r o c e s st h a ta l o wF / Mr a t i oo f t h ei n f l u e n th e l p e dp r o m o t ebc f o r m a t i o n a n da l s oi n d u c et h eg r e a t e s tw a s h o u tr a t ei n at y p i c a lU A S B . T h e r e a s o ni s t h a t f l o ca n dg r a n u l e sc a nb e f o r m e d e f f e c t i v e l yi fs u b s t r a t ef e e d r a t e sa r ek e p t a sc l o s ea s p o s s i b l et ot h a to fb a c t e r i a lg r o w t hr a t e s .H o w e v e r ,t h e r ea p p e a r e dt o b eas u d d e ni n c r e a s ei nt o t a le f f l u e n tV F Ao fA - U A S B( s a m p l i n gp o i n tn o . 5 )b e y o n d d a y3 0 ,r a n g i n g f r o m4 , 9 5 0 - 5 , 1 5 0t o5 , 2 0 0 - 6 , 2 0 0 m g / La sH A ca s s h o w ni nT a b l eB 2 . 5o fA p p e n d i xB . T h i s s u d d e n i n c r e a s ea sa s h o c kl o a d t o t h eM - U A S Br e s u l t e di na d e c r e a s ei ns y s t e mp e r f o r m a n c e s a si l l u s t r a t e di n F i g u r e s 5 . 1 - 5 . 4 .C o m b i n a t i o no f a d i f f i c u l t yi nc o n t r o l l i n gt h es y s t e m l o a d i n gr a t e b e y o n dd a y 3 0a n da na t t e m p tt o m a i n t a i nt h ep H o fM - U A S Bw h i c hd e s t r o y e dt h es l u d g eb e d a n db l a n k e t ,w a sr e s p o n s i b l ef o r t h i sp a r t i c u l a rs i t u a t i o n .T h i s w a s h o u tp h e n o m e n o nd u r i n gt h e s t a r t - u pp r o c e s sw a sa l s o m e n t i o n e db ys e v e r a lo t h e rr e s e a r c h e r s .Z e e u w( 1 9 8 0 )c o n c l u d e d t h a tt h e a c c l i m a t i o np r o c e s so fa nU A S Br e a c t o ri n c l u d e dr o u g h l y3 s t a g e so f a d a p t a t i o n :( a )a d a p t a t i o no f s l u d g et ot h es u b s t r a t ec o m p o s i t i o n- a ni n i t i a ll o a d i n gr a t es h o u l db ek e p tc l o s et ot h em a x i m u mp o t e n t i a lo f s e e ds l u d g e( 0 . 0 4k g C O D / k gV S S I d a y )i n o r d e rt op r e v e n ta n i n h i b i t i o no ft h e b r e a kd o w no fH P r ;( b )i n c r e a s i n go ft h es p e c i f i ca c t i v i t yo ft h es l u d g ea sa r e s u l to f5 6b a c t e r i a l g r o w t h , retention t i m e a n d w a s h o u t p r o c e s sw h i c ho c c u r r e di nt h ef i r s tw e e ko fo p e r a t i o n ;( c ) s l u d g ep e l l e t i z a t i o n- appeared a p p r o x i m a t e l y6 - 7 w e e k s after t h e startu pa n dt h e s l u d g eb e d c o n c e n t r a t i o ni n c r e a s e df r o m 7t o 1 8 k gVSS/m3.( b ) S y s t e m P e r f o r m a n c eI n a c c o r d a n c ew i t ht h e s t a r t - u po f d i f f e r e n ta c c l i m a t i z a t i o np r o c e d u r e s ,a s s h o w ni nF i g u r e s5 . 1 - 5 . 4 ,t h e r e s u l t s i n d i c a t e dt h a taw e l l - a d a p t e ds l u d g ec o u l df o r mw i t h i nap e r i o do f4 - 5w e e k s .T h eo r g a n i c l o a d i n gu p t o 1 . 0 - 3 . 4a n d0 . 5 6 - 1 . 8k g COD.m31d,e q u i v a l e n tt oah y d r a u l i cl o a d i n g u p t o0 . 1 0 - 0 . 2 4a n d0 . 0 6 - 0 . 1 3m”m-do ra no r g a n i cl o a d i n go f0 . 3 6 - 0 . 6 0a n d0 . 2 0 - 0 . 3 3k gC O D / k gV S S - d f o rt h eM - U A S Ba n d t h ee n t i r es y s t e mr e s p e c t i v e l y ,c o u l db es u c c e s s f u l l ya c c o m m o d a t e da t 3 50C . T h i sr e s u l t sh a v ea g r e e dw i t ht h es t u d i e sc a r r i e do u t b yH u l s o f f - P o le t . a l( 1 9 8 3 )o nt h ee f f e c to fs l u d g el o a d i n g rate o n g r a n u l a t i o n i nt h eU A S Bs y s t e m .H ef o u n dthatp e l l e t sf o r m e do n l ya tl o a d i n gr a t e si ne x c e s so f 0 . 6 k gC O D / k gV S S - d ,w h i l e a t0 . 3k gC O D / k gV S S - d , b u l k i n ga n dw a s h o u to c c u r r e d .D u r i n ga c c l i m a t i z a t i o n ,i tw a si n t e r e s t i n gt o n o t e that there w a sal a gp e r i o do fa b o u t2w e e k sf o ra l t e r n a t i v eA ,b e f o r et h es y s t e ms t a r t e dt o break d o w n t h es u b s t r a t e ,w h e r e a sn ol a gp e r i o d appeared i n e i t h e r a l t e r n a t i v eB o rC ( a ss h o w ni nF i g u r e5 . 2 - 5 . 4 ) .T h er e a s o n se x p l a i n i n gt h i sl a gp e r i o dh a v ea l r e a d yb e e nn o t e de a r l i e r .T h es y s t e mappearedt ot a k ea b o u t5 2 ,3 5 ,a n d3 0 - 5 2d a y sf o ra l t e r n a t i v eA ,B ,a n dC t or e a c hp s e u d os t e a d y - s t a t e ,a ta r e m o v a le f f i c i e n c yo f8 6 - 9 1%s o l u b l eC O Da n d9 4 - 1 0 0%V F A5 7( a ss h o w ni n F i g u r e5 . 2 a n d 5 . 3 ) ,r e s p e c t i v e l y .T h e a c c l i m a t i z a t i o np e r i o df o ra l t e r n a t i v eCt o o ka l m o s t t w om o n t h s(a p p r o x i m a t e l y3 0 - 5 2d a y s) ,l o n g e r t h a ne x p e c t e d . T h e p o s s i b l em a j o r c a u s e so f t h i sp a r t i c u l a rs i t u a t i o n a r ea s u d d e n i n c r e a s ei n s y s t e m l o a d i n ga n d / o rad i s t u r b a n c eo fs l u d g eb e da n d b l a n k e t a sm e n t i o n e de a r l i e r . A r a p i di n c r e a s e i nt h eH P r / H A cr a t i o ,a ss h o w ni n F i g u r e 5 . 4 , i n d i c a t e dt h a t t h es y s t e m w a s i n t e r r u p t e da n d / o ru n d e r s t r e s s ,c a u s i n gt h e a c c u m u l a t i o no f H P r( b e c a u s eH2- u t i l i z i n gb a c t e r i a , t of o r m C H4, a r ei n h i b i t e d ) .A ss u c h ,t h e e x c e s so fr e d u c t i o n e q u i v a l e n t si sd i v e r t e di n t ol e s s f a v o u r a b l eb i o c h e m i c a lr o u t e s( u s i n go r g a n i ca c i d s a s a ne l e c t r o ns i n k )r e s u l t i n gi nt h e a c c u m u l a t i o no f H P r( Z o e t e m e i j e r ,1 9 8 2 ) .H o w e v e r ,i t t o o k o n l y ac o u p l eo f w e e k sf o rt h e s y s t e m t or e c o v e rb yi t s e l f , n a t u r a l l y .D e s p i t et h i sp r o b l e m ,a l t e r n a t i v eC ( b e t w e e nd a y s2 0 - 3 0 )s e e m st o b es l i g h t l yb e t t e rt h a na l t e r n a t i v e sA a n dB ,i nt e r m so f a v e r a g es y s t e mr e m o v a le f f i c i e n c ya n de f f l u e n tq u a l i t y a ss h o w ni n T a b l eB 1 . 1o f A p p e n d i xB .Ap o s s i b l ee x p l a n a t i o ni s t h a tt h eA - U A S B o ft h e a l t e r n a t i v eC w a sp r o p e r l y a c c l i m a t i z e da n dl o a d e ds t e p - w i s e ,w i t h w e l la d a p t e ds e e ds l u d g e .T h i sh e l p e dt og e n e r a t es u f f i c i e n tv o l u m eo fr e a d i l yb i o d e g r a d a b l eV F A ’ sf o rm e t h a n o g e n e s i si nt h eM - U A S B ;w h i c hw a ss e e d e dw i t hs l u d g ef r o mt h ea n a e r o b i cd i g e s t e ro f L i o n ’ sG a t et r e a t m e n tp l a n t .W i t hg r e a t e rv a r i e t i e so f a c e t o g e n sa n dm e t h a n o g e n si nt h i st y p eo fd i g e s t e rs l u d g e ,c o u p l e dw i t ha p r o p e rs t a r t - u po ft h eA - U A S B ,a l t e r n a t i v eCa p p e a r st o a c c l i m a t i z et h e s y s t e mm o r e e f f e c t i v e l ya n de f f i c i e n t l yt h a ne i t h e ra l t e r n a t i v eAo r B .I n t e r m so f n u t r i e n tr e q u i r e m e n t s ,i t a p p e a r st h a te f f l u e n tl e v e l sa n d r e m o v a le f f i c i e n c yo f P04-P t e n dt o f o l l o wt h ep a t t e r n so fb o t hC O Da n d5 8V F Ae f f l u e n t l e v e l s a n d r e m o v a le f f i c i e n c y ; h o w e v e r ,T K Ns e e m e dt oh a v en or e l a t i o n s h i pa t a l lw i t ht h es y s t e m r e m o v a le f f i c i e n c y ,a s s h o w n i nF i g u r eB 1 . 1 o fA p p e n d i xB .T h es u m m a r yo fa v e r a g es y s t e mp e r f o r m a n c ed u r i n g t h ea c c l i m a t i z a t i o np r o c e s s ,u n d e r d i f f e r e n t r u n n i n gc o n d i t i o n sw a si l l u s t r a t e di n T a b l e B L 1 o f A p p e n d i x B .5 . 1 . 2 C o n c l u s i o n sS y s t e ma c c l i m a t i z a t i o ni s o n eo f t h em o s tc r u c i a ls t e p s t o s e c u r e ar e l i a b l e s y s t e mp e r f o r m a n c e .C a r e f u l a n dp r o p e r s y s t e ms t a r t - u pa n d a c c l i m a t i z a t i o nr e s u l t si n t h ep r o d u c t i o no f a na c t i v ea n d e f f e c t i v eg r a n u l a rb i o m a s ss l u d g e(p e l l e t s) ,w h i c hs u b s e q u e n t l yc r e a t e s a ne f f e c t i v es y s t e m r e m o v a le f f i c i e n c ya n dg e n e r a t e ss i g n i f i c a n ta m o u n t so f C H4g a s .A c c o r d i n gt o t h er e s u l t so b t a i n e dd u r i n g t h ea c c l i m a t i z a t i o np r o c e s s ,t h ef o l l o w i n gc o n c l u s i o n sc a nb e m a d e :( 1 )A s t e p - l o a d i n gs c h e m e ,s t a r t i n ga tas l u d g e l o a d i n gr a t eo f1 . 2g C O D I L - dw i t has e e ds l u d g er a t i o o f 1 : 1( b y v o l u m e ) ,a p p e a r st o b ea n e f f e c t i v e m e a s u r et oa c c l i m a t i z et h e s y s t e m .S a l t s o fC a2a n dP 043s e e mt op l a y am a j o rp a r t i nt h e i n c r e a s eo f t h es l u d g es e t t l e a b i l i t y .( 2 )T h e“ w a s h o u tp h e n o m e n o n ”o c c u r sw i t h i n 2w e e k s o ft h ep r o c e s sa c c l i m a t i z a t i o n ,a ta s l u d g e l o a d i n go f l e s s t h a n1 . 2 g C O D / L - do r 0 . 3 6 k gC O D / k gV S S - d .( 3 )A c c l i m a t i z a t i o na l t e r n a t i v eC ,s e e d i n gt h eA - U A S Bw i t ha c c l i m a t i z e ds y n t h e t i cs e e ds l u d g ea n dt h e M - U A S Bw i t hs l u d g ef r o m t h eL i o n ’ sG a t ea n a e r o b i cs l u d g ed i g e s t e r ,i st h e m o s te f f e c t i v ea n dp r a c t i c a l m e t h o dt o a c c e l e r a t et h ea c c l i m a t i z a t i o n5 9p r o c e s s , s i n c ea n a e r o b i c d i g e s t e rs e e d s l u d g ei s a l r e a d y a v a i l a b l ea t s u f f i c i e n tv o l u m e sf o rat y p i c a lf u l l s c a l eU A S B p r o c e s s .T h e s y s t e ms t a r t s t o w a s h o u tt h e M L V S Si m m e d i a t e l ya f t e ra c c l i m a t i z a t i o na n d c o m p l e t e st h e p r o c e s s w i t h i n4 - 5 w e e k s , w i t h8 6 - 9 1%C O D( s o l . ) a n d 9 4 - 1 0 0%t o t a l V F Ar e m o v a le f f i c i e n c i e s .6 05 . 2E X P E R I M E N T A LD E S I G NT h i s s e c t i o nd e s c r i b e sw i t ha s e a r c hf o r a n o p t i m u m “ b e s t k n o w n ”o p e r a t i n gc o n d i t i o nb y d e t e r m i n i n gt h ee f f e c t sa n d i n t e r a c t i o no f S R a n dR Ro n t h e r e s p o n s e sa n dp r o c e s sp e r f o r m a n c eu n d e r d i f f e r e n tr u n n i n g c o n d i t i o n s .T h e r e s u l t sa r et h e n u s e d t o l o c a t et h e“ b e s t k n o w n ”r u n n i n g c o n d i t i o n , w h i c h p r o v i d e ss u p e r i o rs u p e r n a t a n tq u a l i t ya n dr e a s o n a b l em e t h a n eg a sp r o d u c t i o n ,b ya n a p p l i c a t i o no fY a t e ’ s a l g o r i t h ma n dR e s p o n s eS u r f a c e M e t h o d( R S M )( B o x ,1 9 6 9 ) .T h e s ea p p l i c a t i o nt e c h n i q u e so f e x p e r i m e n t a ld e s i g n sa r ei n i t i a l l y u s e da s m a j o rt o o l st o h e l pd i r e c tt h en e x ta p p r o p r i a t ea n de f f e c t i v em o v e so ft h e e x p e r i m e n t a ld e s i g nt o w a r dt h e o p t i m a l“ b e s t k n o w n ”o p e r a t i n gc o n d i t i o n .T h ee f f e c t i v e n e s so f at w o - p h a s ea n a e r o b i cd i g e s t i o n( U A S B - U A S B ) s y s t e mt o s t a b i l i z et h ep a r t i c u l a t es u b s t r a t eu n d e rd i f f e r e n tr u n n i n gc o n d i t i o n si s t h e n e v a l u a t e d .S t e p -l o a d i n gr a t ee x p e r i m e n t sa r e f u r t h e ru n d e r t a k e nt ol o c a t et h e o p t i m u ma n dm a x i m u ms y s t e mh y d r a u l i ca n d / o ro r g a n i cl o a d i n g c a p a c i t i e s .F u r t h e r m o r e ,t h ee x p e r i m e n t ss h o u l dp r o v i d ei n f o r m a t i o no nt h er e q u i r e dr e c o v e r yp e r i o d ,a f t e ra s e r i o u sw a s h o u to f t h ea c t i v eb i o m a s sh a so c c u r r e d .E v a l u a t i o no f b a s i ck i n e t i c si s a l s om a d e .T h ef e a s i b i l i t yo ft h i st w o - p h a s e( U A S B - U A S B )p r o c e s sc a nt h e nb ee v a l u a t e di nt e r m so fs y s t e me f f e c t i v e n e s s(a c c l i m a t i z a t i o na n d p e r f o r m a n c e )a n ds y s t e ms u i t a b i l i t y( m a x i m u ma n do p t i m u mh y d r a u l i ca n d / o ro r g a n i cl o a d i n gc a p a c i t ya n ds y s t e mr e c o v e r y ) .M o d i f i c a t i o n st od e s i g nc r i t e r i aa n do p e r a t i o np r o c e d u r e sa r ep r o p o s e da tt h e e n do ft h i ss e c t i o n .5 . 2 . 1O p t i m u m“ b e s tk n o w n ”O p e r a t i n gC o n d i t i o n6 1T h e t e r m“ b e s t k n o w n’i n t h i sp a r t i c u l a rs i t u a t i o n ,i s d e f i n e d a s ar u n n i n gc o n d i t i o n t h a t p r o v i d e st h em a x i m u m s y s t e m C O D r e m o v a le f f i c i e n c ya n d C H4g a sp r o d u c t i o nu n d e rac e r t a i nr e g i m eo f p H , t e m p e r a t u r e ,a n d i n f l u e n tf l o w r a t e .T o l o c a t et h eo p t i m u m“ b e s t k n o w n ”o p e r a t i n gc o n d i t i o n , r e g a r d i n gS Ra n d R R , a p r e v i o u s l ys u c c e s s f u lr u n n i n g c o n d i t i o n ,d u r i n gt h ea c c l i m a t i z a t i o np r o c e s s , w a s u s e d a sas t a r t i n gc o n d i t i o n ;a l s o ,a n o t h e r s e to f r u n n i n g c o n d i t i o n s ,a s s h o w ni n T a b l e4 . 2 o fS e c t i o n4 . 2 . 1 ,w a sa l s oi m p l e m e n t e d .T h e r e s p o n s e sa n d e f f i c i e n c y o f e a c hr u n n i n gc o n d i t i o nw e r eu s e dt o e v a l u a t et h e e f f e c t so fS R / R Ro ns y s t e m p e r f o r m a n c e ,t h e e f f e c t i v e n e s so f t h et w o -p h a s e ( U A S B - U A S B )c o n c e p t ,a n d t h e l o c a t i o no f t h e“ b e s tk n o w n ”r u n n i n gc o n d i t i o n .5 . 2 . 1 . 1E f f e c t sa n dI n t e r a c t i o n o f S l u d g eR a t i o( S R ) a n d R e c y c l eR a t i o ( R R )T o oh i g h a n R R c a n d e s t r o yt h es l u d g eb e d a n d w a s ho u tt h ea c t i v e b i o m a s sf r o mt h es y s t e m ,b u t t o ol o w a n R Rc a na l s or e d u c e t h es y s t e mr e m o v a l e f f i c i e n c yb yr e d u c i n gt h ec h a n c e s o fb e t t e r c o n t a c tb e t w e e nm i c r o o r g a n i s m sa n d s u b s t r a t e sa n dd e c r e a s i n gt h es y s t e mb u f f e r i n gc a p a c i t y .E q u a l l y i m p o r t a n t ,t o o - h i g ha n d - l o wa nS R c a ns i g n i f i c a n t l ya f f e c tt h e s y s t e mp e r f o r m a n c e ,s i n c et h ep r i m a r ya n ds e c o n d a r ys l u d g e sa r e c o m p o s e do fe x t r e m e l yd i f f e r e n tn u t r i e n tc o n c e n t r a t i o n s ,t h u s a f f e c t i n go r g a n i cl o a d i n gc a p a c i t y .T h ee f f e c t sa n d i n t e r a c t i o no f b o t hR R a n dS R ,a sw e l la s t h e i n i t i a lo p t i m u mr a n g eo ft h e s et w oi n f l u e n t i a lc o n t r o lp a r a m e t e r s ,m u s tb e a n a l y z e da n di d e n t i f i e dp r i o rt op r o c e e d i n ga n yf u r t h e rt o w a r do p t i m u ma n dm a x i m u ml o a d i n g c a p a c i t yo ft h eU A S B6 2U A S Bs y s t e m .I n t h i s p a r t i c u l a rs i t u a t i o nt h a to n l y t h ea c c l i m a t i z a t i o nr u n n i n gc o n d i t i o ni sk n o w n ,a n “ E v o l u t i o n a r yO p e r a t i o nP r o c e s s( E O P ) ”u s i n gY a t e ’ sa l g o r i t h m sw i t h2s t a n d a r de r r o r s ( S . E . )i sa n e f f e c t i v e t e c h n i q u et o l e a dt h e e x p e r i m e n t a ld e s i g n t o w a r dt h eo p t i m a l “ b e s tk n o w n ” r u n n i n gc o n d i t i o n p r o v i d i n gs u p e r i o r s u p e m a t a n tq u a l i t ya n dr e a s o n a b l es y s t e m r e m o v a le f f i c i e n c y .A t e a c hs t e po fE O P ,a r e f e r e n c er u n n i n g( b e s tk n o w n ) c o n d i t i o nw i t ha n o t h e r f o u ra p p r o p r i a t er u n n i n gc o n d i t i o n si s d e s i g n e da n di m p l e m e n t e d .C a l c u l a t i o n so f e f f e c t ,i n t e r a c t i o n ,p h a s em e a n ,a n dc h a n g e i n m e a no ft h e s ed a t aa r em a d ea n da n a l y z e dw i t ha n a p p l i c a t i o no f S t e e p e s tA s c e n tt e c h n i q u e .I fn e c e s s a r y ,a n o t h e rs e to f e x p e r i m e n t a ld e s i g n( b e s tk n o w nr u n n i n gc o n d i t i o no ft h ep r e v i o u ss e t p l u sa n o t h e rf o u r d e s i g n e dr u n n i n gc o n d i t i o n s )h a st o b e s e t u pi fm a g n i t u d e so f e f f e c ta n dc h a n g ei n m e a n a r es i g n i f i c a n t ,c o m p a r e dw i t h2 S . E . .O nt h eo t h e rh a n d ,i f t h e s e m a g n i t u d e sa r en o t s i g n i f i c a n tc o m p a r e dw i t h 2S . E . , i tm e a n s t h er e f e r e n c eb e s t k n o w nc o n d i t i o ni sc l o s e dt o t h e v i c i n i t yo ft h eo p t i m a l s y s t e mo p e r a t i n gc o n d i t i o n .B ya p p l y i n gaY a t e ’ sa l g o r i t h mw i t ht w os t a n d a r de r r o r s(B o x , 1 9 6 9)o nt h es e l e c t e dp a r a m e t e r so fS e q u e n c e1a n d2 e x p e r i m e n t s ,t h ee f f e c t ,i n t e r a c t i o n ,p h a s em e a n ,a n dc h a n g ei nm e a nw e r ec a l c u l a t e da n ds u m m a r i z e di n T a b l e5 . 1 .A d e t a i l e dc a l c u l a t i o no f t h ea b o v es t a t i s t i c a lp a r a m e t e r s ,b a s e do nt h er e p l i c a t e dv a l u e sa tp s e u d os t e a d y - s t a t ec o n d i t i o no fe a c hr u n n i n gc o n d i t i o ni nS e q u e n c e1 a n d2e x p e r i m e n t s ,i sd e m o n s t r a t e di nT a b l eC 2 . 1o f A p p e n d i xC . F r o mT a b l e5 . 1 , i ti s a p p a r e n t ,a p a r tf r o mt h ee f f e c to f 2 s t a n d a r de r r o r s ,t h a tS Ra n dR Rh a v eas i g n i f i c a n te f f e c to nt h e e f f l u e n tJ a l e : 5 .1 S I . i r T 1 u T 1 a r ’ f . . è f f é i t s( S R . a i i il l/c h a n g ei nm e a nd u r i n g t h es e q u e n c e1a n d2e x p e r i m e n t s. R s p o n s e . :p a r a m e t e r s• l n t é r a-t i o n: .• : : P h a S e :S e q u e n c e 1E f f l u e n t , m g I Lo r m g i L a sH A cC 0 D ( s o l . )1 4 5 4- 3 4 6 0 4 8 6 3 2 0 7 2 3 5 7 1 8 6 / 1 6 7V F A ( t o t . ) 1 2 6 2 - 1 1 9 6 - 8 0 2 1 9 6 5 1 7 3 4 1 4 4 1 / 1 2 8 8P 0 4 - P8 5- 2 1 3- 81 4 2 1 2 2 7 2 . 3 3 / 6 4 . 6 4S y s t e m R e m . , %C 0 D ( s o L ) - 2 4 . 4 6 5 9 . 7 5 - 1 . 45 2 . 9 3 - 3 0 . 5 66 . 4 2 / 5 . 7 5P 0 4 - P - 5 1 . 5 2 8 1 . 2 8 1 6 . 9 9 2 4 . 2 8 - 6 0 . 3 1 2 1 . 7 6 / 1 9 . 4 4C H 4g a s% C H 4 - 7 . 4 9 5 . 3 1 - 5 . 3 1 6 7 . 9 1 6 . 3 2 . 7 9 / 2 . 5Y i e l d s 0 . 7 7 - 0 . 6 1 0 . 0 4 1 . 7 70 . 0 61 . 0 5 / . 9 5S e q u e n c e 2E f f l u e n t , m g I L o r m g / I .a sH A cC O D ( s o l . )- 3 6- 1 5 - 8 4 4 3 0 - 1 4 6 1 7 3 / 1 5 5V F A ( t o t . ) - 1 3 . 56 3 . 5- 1 3 . 58 3- 2 0 5 1 9 7 / 1 7 6P 0 4 - P - 4 3 . 5 - 7 8 . 5 4 0 . 53 9 3 33 8 . 4 9 / 3 4 . 4S y s t e m R e m . , %C O D ( s o l . ) 1 . 0 1 - 0 . 8 3 1 . 1 59 3 . 8 1 2 . 4 6 2 . 0 7 / 1 . 8 5P 0 4 - P 1 0 . 3 1 2 9 . 2 1 - 8 . 5 48 3 . 8 3- 1 0 . 21 1 . 2 7 / 1 0 . 0 7C H 4g a s% C H 4- 3 . 0 9 - 0 . 3 8- 1 . 8 1 7 2 . 6 200 . 9 8 / 0 . 8 8Y i e l d s 0 . 2 7 - 0 . 3 4- 0 . 5 31 . 9 4 0 . 1 0 . 2 9 / 0 . 2 7N o t e : 1.=2 s t a n d a r d Ø f t o o f . é f f é c t , i h t é r ä c t i o n . p h ã s e m e a r2 #= 2 s t a n d a r d e r r o r s o f c h a n g ei nm e a nN e g a t i v e ( — y e ) r e s p o n s e m a g n i t u d e , i f s i g n i f i c a n t ,c o m p a r e dw i t h2SE m e a nb e t t e rp e r f o r m a n c ec a nb e a c h i e v e db yd e c r e a s i n g S R , R R , a n d l o r ac o m b i n a t i o n o f b o t hD e t a i l e d c a l c u l a t i o n w a s i l l u s t r a t e d i n T a b l eC 2 1 o f A p p e n d i x C6 364and removal efficiency of COD(sol.) and P04-P in the Sequence 1 experiment. However,the effect of SR appears to be of a greater magnitude than that of RR and only theinteraction (SR*RR) of effluent COD is significant. This may suggest that the systemCOD removal efficiency is probably governed by the anaerobic stabilization processesand depends largely on the SR and RR factors to increase the contact betweenmicroorganisms and substrates, bufferring capacity, and nutrient requirements; whereas,the removal of P04-P, without any interaction, is mostly a chemical reaction, affectedstrongly by the influent TP in the feed SR, thus resulting in the precipitation of Ca2 andP043 salts inside the reactor.The large relative magnitudes of the main effect, interaction, and change in meanson most of the responses in the effluent and removal efficiency, compared with 2 SE.in the Sequence 1 experiment, indicated that the optimum “best known” runningcondition was still not reached. An additional sequence of running conditions was neededto move toward the optimum condition. Under these circumstances, a “steep ascent”method is the most effective preliminary procedure to direct the next appropriate moveof the experimental operation and thus approaches the optimum running condition. Oncethe linear effect becomes small, further application of the method is unprofitable (Boxet a], 1969).A graphical contour plot, using data from each pseudo steady-state of theSequence 1 experiment, was made, as shown in Figure 5.5. The sequence 2 experimentaloperation was then made by assigning the “best known” condition in sequence 1experiment as a reference running condition, plus another 4 different running conditionsYMAX.81.565I o.86Io3101z(a)240032o0r000V MIN. 48.5V MAX.. 81.58773D552zxC b)72 7256V M(N-48.5Figure 5.5 Surface Responses of Phase I Experiment:(a) Effluent COD (sol.);(b) COD Removal EfficiencAt Pseudo Steady-state under Different Running Conca’ionsNote: x = Recycle Ratio (RR); y = Sludge Ratio (SR)6 6a s s h o w ni n T a b l e 4 . 2 .T h e d e t a i l s o ft h i s “ b e s t k n o w n ” c o n d i t i o nw i l lb ed i s c u s s e di n t h en e x ts e c t i o n .C o m p a r i n g t h e p h a s em e a n s o fb o t hS e q u e n c e1a n d 2 e x p e r i m e n t s ,t h es y s t e m p e r f o r m e dm u c hb e t t e r i n t e r m s o f e f f l u e n tq u a l i t y , C O Dr e m o v a l e f f i c i e n c y ,a n dC H4g a sc o n t e n ta n dy i e l d , i nt h e S e q u e n c e2 e x p e r i m e n t( a s s h o w ni nT a b l e5 . 1 ) . T h e r ew a s a l s o n os i g n i f i c a n te f f e c t o fS R a n d R R o n a l lt h e r e s p o n s e s ,w h e n c o m p a r e dw i t h2 S . E . .T h e s e c o m b i n a t i o n si n d i c a t e d t h a tt h e s y s t e m w a sn o wi n t h e v i c i n i t yo f t h eo p t i m u m“ b e s tk n o w n ” c o n d i t i o np r o v i d i n gt h e m a x i m u mC O Dr e m o v a le f f i c i e n c y .H o w e v e r ,t h e r ew e r e s t i l ls o m ee f f e c t s o fS R o nt h e c o n t e n ta n dr e m o v a l e f f i c i e n c yo fP04-P a n dt h e e f f e c to fR R a n di n t e r a c t i o n( S R * R R )o nt h e C H4 g a s c o n t e n t .A na d d i t i o n a lr u n( S e q u e n c e3e x p e r i m e n ta s s h o w ni nT a b l e4 . 2 )w a st h e nc a r r i e do u tt oe n s u r et h a tt h es y s t e m r e a l l yr e a c h e dt h eo p t i m u m‘ b e s t k n o w n ”r u n n i n g c o n d i t i o n .5 . 2 . 1 . 2‘ E e s tK n o w n ”R u n n i n gC o n d i t i o nB ya p p l y i n gt h es t e e pa s c e n tt e c h n i q u ea sm e n t i o n e de a r l i e r ,a r e s p o n s es u r f a c eo f t h eS e q u e n c e1e x p e r i m e n t a lr u n s a ss h o w ni n T a b l e4 . 2 ,w i t h r e s p e c tt oe f f l u e n tC O D( s o l . )a n d C O Dr e m o v a le f f i c i e n c y ,i si l l u s t r a t e di nF i g u r e5 . 5 .A ss h o w n ,t h ec o n t o u rl i n e so fb o t hC O Dr e m o v a le f f i c i e n c ya n de f f l u e n tC O Dt e n dt om o v et o w a r d st h eb e s tk n o w nr u n n i n gc o n d i t i o n( e x p e r i m e n t a lr u nn o .0 : S R 8 O / 2 0a n d R R 4 / 7 ) ,w h e r e8 6 . 0 9%C O D( s o l . )r e m o v a le f f i c i e n c ya n d8 6 1 m g / Lo fe f f l u e n tC O D( s o ! . )w e r e o b t a i n e d .I ti s q u i t ei n t e r e s t i n gt o n o t et h a tt h er u n n i n gc o n d i t i o no fS R 5 O / 5 0a n dR R 2 / 4w a s t h ew o r s t674-3.5- m—() :.3 - Running ConditionsSR RR(a) 80/20 2/4E 2.5- (b) 80/20 6/10( C ) 50/50 6/106° 2- (d) 50/50 214I1.5- IL HI A-UASB + M-UASB-0.5 -1 10 19 28 37 46 55 64 73 82 91 100Time, days- Figure 5.6 NaOH (0.1 N) AdditionDuring the Sequence 1 Experimentscenario in the Sequence 1 experiment, with 8.81 % COD removal efficiency and theeffluent (so!.) COD of 5950 mg/L. This may have been the result of a large volume of0.1 N NaOH automatically pumped into the reactor to neutralize and maintain the pH‘at 7.0-7.2 (as shown in Figure 5.6), thus destroying the sludge bed and diminishing theCH4 gas production and the system removal efficiency (as shown in Figure 5.7). It isspeculated that a malfunction of the pH sensor in the M-UASB might have played amajor role in this unusual situation. Although results of the worst running condition weresuspected and even without considering them, the overall picture of sequence 1Figure5.7SystemResponsesandPerformanceof Sequence1Experiment:(a)CODRemovalEffidency;(b)EffluentCOD;(c) CH4Content;(d) CH4GasProduction00 80-70-80-50-40-30 iiiJf/J}%70 50 30 10 80 40I I. I IE4?roa.N04•.L•ie3847 Tbn., d.y69experiment still remained moving toward the acclimatization running condition (SR 80/20and RR 4/7). Reseeding and repeating the acclimatization process of the M-UASB, usinga new pH sensor, were made before starting the experiments in Sequences 2 and 3, asdetailed in Table 4.2.A summary of average responses and system performance under different runningconditions (Sequence 1-3) is shown in Table 5.2. As also shown, running condition no.7(SR6O/40 and RR5/8) appeared to perform better in terms of better effluent quality andhigher CH4 gas productivity than those of running condition no.10 (SR8O/20 and RR4/7);however; condition no.10 provided a better P04-P removal efficiency. Finally, as shownin Table 5.2, the choice of running condition no.9 (SR8O/20 and RR5/8) was the optimum“Best known” condition with respect to P04-P removal efficiency, specific CR4 gasproductivity, and CH4 gas production, compared to all other running conditions. Asummary of average responses and performance of the “best known” running conditionis illustrated in Table 5.3. Under this “best known” condition, the system appears toprovide a promising performance with 95, 99, and 90 % removal efficiencies of solubleCOD, total COD, and P04-P, respectively. A low level of soluble effluent COD of 308mg/L is also indicated.5.2.1.3 Two-phase Separation (UASB-UASB)To avoid confusion between a conventional, completely mixed “two-stage”Table52Summaryof AverageResponsesUnderPseudoSteady—stateoftheDifferent DesignediunningConditions(Sequence1,2,and3Experiments)::ExperimentalRUAingConditionaAverageResponsesSequence1Sequence2SequenceS11213145161718911011112LoadingRatecu.m/cu.m—d0.100.140.100.120.120.120.080.120.090.110.090.10KgCOD(Sol)Icu.m—d0.630.970.620.760.750.780.630.910.690.590.590.62KgCOD(Total)Icu.m—d5.706.004.506.355.604.803.954.704.304.254.253.85Effluent QualitySolids,mgILTS714065003480544031303600235526352610260026602600VS4030420013002645900143081511751050620930880TSS270580190280210200230730300300340230TVSS18033016026065100100430155140120100COD,mg!LCOD(Total)2780338051356480490400420445470400425400COD(Sol)2755305548706030460325355350300305280290Inorganics,mg/LNH4—N270360425405455400525515510410390425TKN300385435466459420492483489387557420TP60124230364176747685913214027P04—P209123034096347420231111TotalVFA,mg/LHAG146020501780350780500000020SystemRemovalEfficiencySolids,%TS858091829189939191919392VS918096909795979596979797TSS999899999999999699999999TVSS9999999910010099989999100100COD,%COD(Total)959289839999999999999999COD(Sol)54572349395959596949695Inorganics,%TP6631—6—661463655750764083P04—P854033—949597815891889492MethaneGasFlow,l/dTotal Gas5380353095911071261208785.0083CH4Gas34461410605862.207169505449CH4ProductivitylId344614106058627169505449cu.m/cu.m—d0.751.000.300.201.351.301.381.601.551.101.201.10cu.m/cu.m—d@SC0.700.900.250.201.201.151.251.401.400.901.000.95cu.m/kgCOD(Total)added@SC0.120.150.050.030.200.250.300.300.320.250.250.25NoteExperimentalRunningConditionsSR=SludgeRatio(PrimaryandSecondarySludges)SRRRSRRRRR=RecycleRatio(RecycleandInfluentflow)180/202/4760/405I8operated©walk—incontrolledroomtemperatureat35o280/206/10860/403/6andpHof 5.0—5.3and7.0—7.3for A—andM—UASBs350/506/10980/205/8Intluent feed©4—5oC450/502/41080/20417570/303/61190/105/8670I305/812901103/6:Thble53PeifôrinanceofA:Twó-phaseAnaéróbkS!udgeDigestion: (UASB-UASB)PróoessOperatingConditions IPertormanceUASB-UASBRunningHRT,days9-10Loadingrate,kgCOD(total)Icu.m-d5.00kgVS/cu.m-d2.00Supernatantquality,Solids,mgIlTS2600VS,(%TS)1050(40)SS300VSS,(%TS)155(58)Organics,mgIl(Total)COD470(Fil.)COD310lnorganics,mg/INH4-N510P04-P20TKN490TP90Volatileacids,mg/lHAcnilHPrnillso-HBrnilHBrnilA-HVrnillso-HVrnilHVrnilHHenilTotalVFA,mg/1asHAcnil:TabieS3Perñiaheof:AT*d’phase Araèröblc:SiLdgeOistion:(UASBUA$B):process:at35degreeC/9dayHRT/SR80/20/fiR5/8(cont’dOperatingConditions IPerformanceUASB-UASBMethanegasCH4yieldscu.m/kgVSremoved0.90cu.m/kgCOD(Total)added0.32CH4productionratecu.m/d75vol/culturevol-d1.70%theoreticalCH495Gascomposition,mol%C0227N21.00CH472RemovalEfficiency,%Organics(Total)COD99(Fil)COD97SolidsTSS98InorganicsP04-P87TP56VFA1007 4a n a e r o b i cd i g e s t i o np r o c e s s a n da“ t w o - p h a s e’a n a e r o b i cd i g e s t i o np r o c e s s , i t i sa p p r o p r i a t et o c l e a r l yd i s t i n g u i s ht h e s e t w oc o n c e p t s .T h e“ t w o - s t a g e ”p r o c e s s c o n s i s t so ft w oc o m p l e t e l ym i x e dr e a c t o r sc o n n e c t e di ns e r i e s . T h ef i r s t r e a c t o r s e r v e sa saf e r m e n t e rw h i l et h es e c o n d o n e a c t s m a i n l ya s a s e t t l e ra n d / o rar e s e r v e df e r m e n t e r ,i nc a s eo fe m e r g e n c yo r f a i l u r e o f t h ef i r s t o n e . O f t e n ,t h es e c o n d d i g e s t e rp e r f o r m sp o o r l ya sat h i c k e n e r ,p r o d u c i n gd i l u t e s l u d g e a n d ah i g h s o l i d s s u p e r n a t a n t .T h i s m a yb e t h er e s u l to fa h i g h p r o p o r t i o no f f i n e - s i z e dp a r t i c l e s i n t h e f i r s td i g e s t e r .T h e ya r e p r o d u c e dg e n e r a l l yb ym i x i n ga n dn a t u r a lb r e a k d o w no fp a r t i c l es i z e t h r o u g hb i o l o g i c a ld e c o m p o s i t i o n ,a n d b e c o m es a t u r a t e dw i t hd i g e s t e rg a s .W h e nt h eg a s i st r a n s f e r r e di n t ot h es e c o n dd i g e s t e r ,i tw i l lc o m eO u to f t h es o l u t i o n , f o r m i n gs m a l lb u b b l e s ;t h e s eb e c o m ea t t a c h e dt os l u d g ep a r t i c l e s a n dc r e a t eab u o y a n tf o r c et h a th i n d e r ss e t t l i n g . T h e “ t w o -p h a s e ”c o n c e p t ,o n t h eo t h e rh a n d ,i sa n a t t e m p tt o t a k ea d v a n t a g eo f t h ed i - p h a s i cp h e n o m e n o no f t h ea n a e r o b i cd i g e s t i o np r o c e s s ,b yk e e p i n gt h e r e a c t o r ss e p a r a t e dp h y s i c a l l ya n d p r o v i d i n gt h eo p t i m u me n v i r o n m e n t a lc o n d i t i o n st o s t i m u l a t ea n d / o rp r o m o t et h e h y d r o l y s i s - a c i d i f i c a t i o na n da c e t o g e n e s i s - m e t h a n o g e n e s i si n t h e f i r s ta n ds e c o n dr e a c t o r sr e s p e c t i v e l y .I ns h o r t ,“ P h a s e ”s h o u l db eu s e d f o rp r o c e s s e sw h e nd i f f e r e n tr e a c t i o n so c c u ri n d i f f e r e n tr e a c t o r sa n d“ S t a g e ”s h o u l db ea p p l i e df o r t h es a m er e a c t i o n / p r o c e s so c c u r r i n gi nt h et w oc o n s e c u t i v er e a c t o r s .I ti sa l s o a p p r o p r i a t et oa v o i dt h eu s e o ft h e w o r d“ S t e p s ” ,s i n c ei t i su s u a l l yu s e dt od e s c r i b ev a r i o u st y p e so f r e a c t i o n si e . m e c h a n i s m so fc h e m i c a lr e a c t i o n .T od e t e r m i n ew h e t h e rat w o - p h a s e( U A S B - U A S B )p r o c e s sd o e so c c u r ,3 -d i m e n s i o n a lp l o t so fe f f l u e n tp r o f i l e so b t a i n e da l o n gt h eh e i g h to f b o t hA - U A S Ba n dM7 5U A S Bu n d e rd i f f e r e n t r u n n i n gc o n d i t i o n s , w e r em a d e .A s s h o w n i nF i g u r e5 . 8 ( a ) , i ti sc l e a rt h a t h y d r o l y s i s - a c i d i f i c a t i o np r e d o m i n a t e si nt h eA - U A S B ; t h e a v e r a g el o w c o n c e n t r a t i o no f i n f l u e n ts o l u b l eC O D i n c r e a s e sg r a d u a l l yf r o m t h eb o t t o mu p t o t h e t o p o f t h er e a c t o ru n d e ra l l t e s t e d r u n n i n gc o n d i t i o n sd u r i n g1 4 5 d a y so f t h eS e q u e n c e 2e x p e r i m e n t .I nc o n t r a s t ,t h e a v e r a g eh i g h C O D c o n c e n t r a t i o no f t h e e f f l u e n tf r o mA - U A S B ,f e da t t h eb o t t o mo f M - U A S B ,d e c r e a s e sr a p i d l ya s i te n t e r s t h es l u d g eb e da n d b l a n k e t ,b e f o r el e a v i n gt h e s y s t e ma t t h e t o po f t h er e a c t o r( a s s h o w ni nF i g u r e 5 . 8 ( b ) ) .T h i s m e a n st h a ta c e t o g e n e s i s - m e t h a n o g e n e s i sd o m i n a t e si nt h e M - U A S Ba n dm o s t o ft h er e a c t i o n s o c c u r sa t t h el o w e rp a r to f t h er e a c t o r .T h i s r e s u l ta l s oa g r e e s w i t ht h ew o r kp r e s e n t e db yG h o s h( 1 9 8 4 ) .F i g u r e s5 . 9 a n d5 . 2 6r e c o n f i r ma s i m i l a rs i t u a t i o no f3 - d i m e n s i o n a lp l o t so f e f f l u e n tt o t a lV F Aa n dC O D( s o l ) p r o f i l e s ,i n d i c a t i n g a f e a s i b i l i t yo ft w o - p h a s e( U A S B - U A S B )p r o c e s sp h e n o m e n o nd u r i n gb o t h“ b e s tk n o w n ”o p e r a t i n gc o n d i t i o na n dm a x i m i z a t i o na n d r e c o v e r yp e r i o de x p e r i m e n t s , r e s p e c t i v e l y .I na d d i t i o n ,F i g u r e5 . 1 0s h o w sa s i g n i f i c a n td i f f e r e n c eo fM L V S Sc o n c e n t r a t i o na t t h es l u d g eb e da n db l a n k e tl e v e l s ,c o m p a r e dw i t ht h o s e o f s e t t l i n ga n de f f l u e n t l e v e l s .I n f l u e n tM L V S Sc o n c e n t r a t i o ni n c r e a s e ds i g n i f i c a n t l ya t t h es l u d g eb e da n d b l a n k e tl e v e l sa n dt h e nr e m a i n e da l m o s tc o n s t a n ta t t h ee f f l u e n tl e v e lo fA - U A S B .I nc o n t r a s t , t h e s eh i g he f f l u e n tV S Sc o n c e n t r a t i o n so fA - U A S Bd e c r e a s e ds h a r p l ya f t e rt h e s l u d g eb e da n db l a n k e t l e v e l sa n dr e m a i n e da l m o s tu n c h a n g e di n t h ee f f l u e n to fM - U A S B .A l l t h e s er e s u l t s a p p e a rt oi n d i c a t et h ef e a s i b i l i t ya n d e f f e c t i v e n e s so ft h e t w o - p h a s ea n a e r o b i cs t a b i l i z a t i o n( U A S BU A S B )p r o c e s s ,i nw h i c hm o s to f t h er e a c t i o n so c c u r r e d a tt h e l o w e rp a r t(s l u d g eb e d76Sampllri point no.— Sp.1 So.3 Sp.4 Sp.2I Sampling point no.Sp.8 Sp.7 Sp.6 50.5(b)Lperimsntat running ccnditicnsj [Exper:men1aPenods-jSR RR Days70/30 3/6 1-2970/30 5/8 35.7160/40 5/8 78-1 (c)60/40 3/6 107-145Figure 5.8 COD (soluble) Profiles Along the Reactor Height:Under different runninq conditions(a) A-UASB; (b) M-UASB; (cYRunning ConditionsNote: All sampling locations are illustrated in Fig.4.1El fluent COO. mgJl llhousan)0—II1 8 16 22 25 29 43 50 57 54 71 75 35 92 99102106113120130134141146Time, daysEffluent COO. mg/I (thousand)(a)A1 8 16 22 25 29 43505754 71 75 86 92 99102106113120130134141146Time, days7 7r: L 111 5 2 5 4 35 7 7 18 5 9 9 1 0 6 1 2 0 1 3 4 1 4 5( a )L UT i m e ,d a y s6g g0 0 00 0 1 7 ( 6 )o o L 7 o o o c c f i o o o c / c201 1 51 4 5( b )L UT ’ r n e ,d a y s_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _L n t e d o s 1S RR RD a y s7 0 / 3 03 / 61 - 2 97 0 / 3 05 / 83 6 - 7 16 0 / 4 05 / 87 8 - 1 0 6( c )6 0 / 4 03 / 61 0 7 - 1 4 5F i g u r e5 . 9T o t a lV F A P r o f i l e s A l o n gt h eR e a c t o r H e i g h t :U n d e r D i f f e r e n tR u n n i n gC o n d i t i o n s( a )A - U A S B ;( b )M - U A S B ;( c ) R u n n i n g C o n d i t i o n sN o t e :A l ls a m p l i n gl o c a t i o n s a r e I l l u s t r a t e dI n F I g . 4 . 1780i1 15 25 43 57 71 85 99 106 120 134 145 (a)Time, days(7).J2OOOOOOOOCCU/8) f15 25 43 57 71 85 99 106120134145Time, days (b[iiri.nring conditions. [€xperimentatP.erlàdsjSR RR Days70/30 3/6 1-2970/30 5/8 35-7160/40 5/8 78-106 Cc)60/40 3/8 107-145Figure 5.10 MLVSS Profiles Along the Reactor Height:Under Different Running Conditions(a) A-UASB; (b) M-UASB; (c) Running ConditionsNote: All sampling locations are Illustrated in Fig.4.17 9a n d b l a n k e t l e v e l s)o f b o t h A - U A S B a n dM - U A S B .A s i n a r i( 1 9 8 1 ) a n d H a r p e r( 1 9 8 6 )r e p o r t e da s i m i l a rs i t u a t i o nw h e r e b yt h e c o n s t a n t p r o d u c t i o no fH P ra n d / o rH B ua c i d si n t h ef i r s tr e a c t o r w a s b e n e f i c i a lf o r t h em e t h a n o g e n i cr e a c t o r ,s i n c e i t e n a b l e dt h ed e v e l o p m e n to f a h e a l t h yp o p u l a t i o no f o b l i g a t e h y d r o g e np r o d u c i n ga c e t o g e n i c ,( O H P A ) ,b a c t e r i aa n d t h e a s s o c i a t e dh y d r o g e n - o x i d i z i n gm e t h a n o g e n s ;t h i s e n s u r e dt h er a p i d a s s i m i l a t i o no ft h e s ea c i d si n t h es e c o n dr e a c t o r .5 . 2 . 1 . 4C o n c l u s i o n sW i t ha na p p l i c a t i o no fa 2b y 2f a c t o r i a ld e s i g ne x p e r i m e n ta n dR e s p o n s eS u r f a c eM e t h o d( R S M ) ,t h ee f f e c t a n d i n t e r a c t i o no f S R a n dR Ro n t h es y s t e mr e s p o n s e sa n dp e r f o r m a n c ew e r ec a l c u l a t e d .A no p t i m u m“ b e s tk n o w n ” r u n n i n gc o n d i t i o nw a s l o c a t e d ,w i t ha n i n t e r p r e t a t i o no f t h ee f f e c ta n di n t e r a c t i o no fS Ra n d R R o nt h e r e s p o n s ep a r a m e t e r sa td i f f e r e n ts e q u e n c e so f t h ee x p e r i m e n t .T h er e s u l t so ft h i si n v e s t i g a t i o nc a nb es u m m a r i z e da sf o l l o w s :( 1 )A s t e e pa s c e n tt e c h n i q u e ,o n eo f t h em o s tp r o m i s i n gR S Ma p p r o a c h e s ,a p p e a r st ob ea ne f f e c t i v em e a s u r ei nd i r e c t i n ga na p p r o p r i a t es t e po ft h ee x p e r i m e n t a ld e s i g nt o w a r dt h eo p t i m u m“ b e s tk n o w n ”r u n n i n gc o n d i t i o n ,i nc a s e sw h e r et h e s ec o n d i t i o n sa r ef a i r l yr e m o t eo ru n k n o w n ,( l i k et h o s eo ft h eS e q u e n c e1e x p e r i m e n t ) .( 2 )T h e e f f e c to fS R o nt h e e f f l u e n tC O Da n d P04-P w a sg r e a t e rt h a n t h a to fR Ra n do n l yt h ei n t e r a c t i o no fS R a n dR Ro n t h ee f f l u e n tC O Dw a ss i g n i f i c a n ti n t h e8 0S e q u e n c e1 e x p e r i m e n t s .H o w e v e r ,t h e r e w e r en o s i g n i f i c a n te f f e c t s a n d i n t e r a c t i o n so fS R a n d R R a n yo f t h e r e s p o n s ep a r a m e t e r s i n t h eS e q u e n c e2 e x p e r i m e n t s , w i t ht h ee x c e p t i o no f S R o n t h e e f f l u e n ta n d r e m o v a le f f i c i e n c y o f P 04- P ,a n d R R o n t h e% C H4c o n t e n t ( w h e r ea s l i g h t e f f e c tw a sd e t e c t e d ) .( 3 )T h eo p t i m u m “ b e s t k n o w n ”r u n n i n gc o n d i t i o nw a sS R 8 0 1 2 0a n d R R 5 / 8 , w i t hr e s p e c t t oP 04- P r e m o v a le f f i c i e n c y , s p e c i f i cC H4 g a s p r o d u c t i v i t y ,a n d C H4 g a sp r o d u c t i o n .( 4 ) T h e f e a s i b i l i t yo ft w o - p h a s es e p a r a t i o no f a n a e r o b i c d i g e s t i o no f s e w a g es l u d g ew a sc o n f i r m e d .H y d r o l y s i s - a c i d i f i c a t i o na n d a c e t o g e n e s i s - m e t h a n o g e n e s i sd o m i n a t ei nt h eA -a n d M - U A S B s ,r e s p e c t i v e l y .I na d d i t i o n ,i t i sq u i t e p r o b a b l e t h a tm o s t o f t h er e a c t i o n si n s i d et h eM - U A S B o c c u r r e da t t h e l o w e rp a r t o f t h er e a c t o r(s l u d g eb e d a n db l a n k e t) .5 . 2 . 2 M a x i m u mL o a d i n gC a p a c i t ya n dR e c o v e r yP r o c e s sT h e c o n v e n t i o n a la n a e r o b i cd i g e s t i o np r o c e s s h a s , u n t i lr e c e n t l y , b e e nc o n s i d e r e dt ob e u n p o p u l a ra n dn o tf e a s i b l e f o r t r e a t m e n to f a h i g h - s t r e n g t ho r g a n i cw a s t e ( s u c ha ss e w a g es l u d g e )u n d e r s h o r t r e t e n t i o nt i m e s ,s i n c ei t i st o o s e n s i t i v e t o v a r i o u se x t r a n e o u sf a c t o r sa n d u n a b l e t or e t a i n a s i g n i f i c a n ta m o u n to f v i a b l e s l u d g eu n d e r h i g hl o a d i n gc o n d i t i o n s .H o w e v e r ,i ti sn o wp o s s i b l ea n df e a s i b l e t o i n s t a l lw e l l - f u n c t i o n i n g ,f u l l - s c a l ea n a e r o b i cf a c i l i t i e so p e r a t i n g a th i g h l o a d i n gr a t e s .A l lm o d e r n “ h i g hr a t e ” a n a e r o b i c8 1p r o c e s s e sa r eb a s e do n t h e p r i n c i p l e so fh i g h v i a b l eb i o m a s sr e t e n t i o na n d s l u d g ei m m o b i l i z a t i o n( i e .f i x a t i o n ) .A t l e a s t t w o m e c h a n i s m sa r ei n v o l v e dh e r e : ( i ) t h e f o r m a t i o no f h i g h l ys e t t l e a b l e s l u d g ea g g r e g a t e s , c o m b i n e dw i t he a r l y g a ss e p a r a t i o na n d s l u d g es e t t l i n g ;a n d ( i i )a t t a c h m e n ta n d e n t r a p m e n to f b a c t e r i aa n d s l u d g ea g g r e g a t e s t o a h i g hd e n s i t yp a r t i c u l a t ec a r r i e r ,o r p a c k i n g m a t e r i a l , s u p p l i e dt o t h e r e a c t o r ( L e t t i n g a ,1 9 8 3 a ) .T h eU A S B i sc o n s i d e r e dt o b e o n e o f t h e m o s ts u c c e s s f u l a n d p r o m i s i n g p r o c e s s e so f t h em o d e r nh i g h - r a t e a n a e r o b i cd i g e s t i o nc o n c e p t . I t h a sl o n gb e e nr e c o g n i z e dt h a t t h eU A S Bp r o c e s s h a ss u p e r i o rf l o c c u l a t i o na n ds e t t l i n g a b i l i t i e s ,a sw e l l a s b e i n ga b l et om a i n t a i nah i g hs o l i d sr e t e n t i o nt i m e , u n d e rah i g ho r g a n i c l o a d i n g r a t e .L e t t i n g a( 1 9 7 9 b )s u g g e s t e dt h a th i g hs e t t l e a b i l i t ya n d s p e c i f i ca c t i v i t yo f t h ea n a e r o b i cs l u d g e w e r et h em a i np r e r e q u i s i t e si na c h i e v i n gh i g h l o a d i n gr a t e s .T o a c c o m p l i s ht h i s t a r g e t ,a t l e a s t 3c o n d i t i o n sm u s t b ea p p l i e d : ( a )c a r e f u ls t a r t - u po f t h e p r o c e s s ; ( b )m a i n t e n a n c eo ff a v o u r a b l ec o n d i t i o n sf o rf l o c c u l a t i o na n dg r o w t h ;a n d ( 3 )p r o m o t i o no f t h i c k e n i n g .U n d e rt h e s er e q u i r e m e n t s ,t h e s y s t e mw a sl o a d e d s t e p - w i s e l y ,b y k e e p i n gt h e b e s tk n o w nr u n n i n gc o n d i t i o n( S R 8 O / 2 0a n dR R 5 / 8 ) f r o mt h e p r e v i o u ss e c t i o na s as t a r t i n gp o i n t . T h es y s t e ml o a d i n g r a t ew a sn o ts t e p p e d u pu n t i l t h es y s t e m w a so p e r a t e da s l o n ga s 2 - 3s y s t e mH R Ta n d / o r8 0 % r e m o v a le f f i c i e n c yw a sa c h i e v e d .P r i o r t o d i s c u s s i n gt h er e s u l t so f m a x i m i z a t i o na n d r e c o v e r yp e r i o d ,t h e f o l l o w i n gt e r m sa n da p p r o a c h e su s e di n t h i sp a r t i c u l a re x p e r i m e n t ,s h o u l db ec l e a r l yd e f i n e d :( a ) M a x i m u ml o a d i n g c a p a c i t y- i st h e p o i n t w h e r et h e r ew a sn o s y s t e mr e m o v a la t a l l ,w i t h t h ei n f l u e n ta n d e f f l u e n tC O Dc o n c e n t r a t i o n sb e i n ge q u a l .8 2( b )R e c o v e r yp r o c e s s - i st h e a p p r o a c h t o r e c o v e rt h e s y s t e m b y r e d u c i n gt h eo r g a n i cl o a d i n g r a t e ,s t e p - b y - s t e p ,a n da n a l y z i n gt h e p e r c e n t a g eo fs y s t e mr e c o v e r ya te a c h s t e po f l o a d i n gr e d u c t i o na f t e rac o m p l e t es y s t e m f a i l u r e .( c )O p t i m u mo p e r a t i n gc o n d i t i o n- i st h e o p t i m u mp o i n t o fS Ra n d R R w h e r et h eo p t i m i z a t i o no fs y s t e mC O Dr e m o v a l e f f i c i e n c ya n dm e t h a n eg a sp r o d u c t i o n w e r ea c h i e v e d .T h e r e s u l t s o f s y s t e mm a x i m i z a t i o n , p r o c e s s f a i l u r e ,r e c o v e r yp e r i o d , s y s t e mr e c o v e r y ,a n d o p t i m u mo p e r a t i n gc o n d i t i o n sa r ed i s c u s s e di n t h e f o l l o w i n gs e c t i o n s .8 35 . 2 . 2 . 1M a x i m u mL o a d i n gC a p a c i t yA s t h eo r g a n i c l o a d i n gr a t e i n c r e a s e ss t e p - b y - s t e pa n df i n a l l y o v e r l o a d st h e s y s t e m ,i t i si m p o r t a n tt om o n i t o r w h e t h e rt h e s y s t e mr e a c h e s t h e p o i n to f c o m p l e t e f a i l u r e .S e v e r a lf a c t o r s h a v et o b ec o n s i d e r e d ,i n c l u d i n g h o w t oi d e n t i f yw h e t h e rt h es y s t e m i s c l o s et ot h e c r i t i c a lp o i n t ; w h a tp a r a m e t e r ss h o u l d b e m e a s u r e d ;w h a t o p t i o n sa r e a v a i l a b l e ;a n dh o wt o c o n t r o lt h e m .I n g e n e r a l ,f e e ds t o p p a g e , i n f l u e n tl o a d i n g r e d u c t i o n ,e f f l u e n tr e c y c l e , a n da l k a l i n e a d d i t i o na r e r e c o m m e n d e df o rr e c o v e r i n gt h e s y s t e ma f t e r a s e r i o u ss h o c kl o a d a n d / o rf a i l u r e .A c o m b i n a t i o no f s t e p - l o a d i n gr e d u c t i o na n d r e c y c l e w a ss e l e c t e da sa p r a c t i c a la n d e f f e c t i v ea p p r o a c ht o t h i sp a r t i c u l a r c a s e .( a ) P r o c e s sF a i l u r eA l t h o u g ht h i st w o - p h a s eU A S B - U A S Bp r o c e s si sd e s i g n e d t o p r o v i d eo p t i m u mc o n d i t i o n st o s t i m u l a t et h e g r o w t ho f a c i d o g e n sa n dm e t h a n o g e n si n t h eA - a n dMU A S B s r e s p e c t i v e l y ,p r o c e s sf a i l u r ec a n s t i l lo c c u r , i f t h es y s t e m i s c o n t i n u o u s l ya n dc o n s t a n t l yo v e r l o a d e d .T h i sc a n s l o w l y t u r nt h e M - U A S Bi n t o as i n g l e - s t a g e d i g e s t e r ,w h e r eb o t h a c i d o g e n sa n dm e t h a n o g e n sc o m p e t e f o r s u b s t r a t eu t i l i z a t i o na n d g r o w t h .I fo v e r l o a d i n gc o n t i n u e s w i t h o u ta n y e f f e c t i v er e m e d i a la c t i o n st a k e n ,t h es y s t e mw i l le v e n t u a l l yf a i l .B e t t e r u n d e r s t a n d i n go fm i c r o b i o l o g i c a la n db i o c h e m i c a lr e a c t i o n s h a sl e a d t os t a b i l i t yi m p r o v e m e n to f t h e a n a e r o b i cd i g e s t i o np r o c e s s . I ti s n o w k n o w nt h a t V F A sa n d8 4h y d r o g e nc a n b ef o r m e dm o r e r a p i d l yt h a n t h e y a r e r e m o v e d ,u n d e r h i g h l o a d i n gr a t ea n d / o ra s u d d e ni n c r e a s ei n o r g a n i c l o a d i n g ( Z o e t e m e i j e r ,1 9 8 2 ) .U n d e rt h i s c o n d i t i o n ,a c e t o g e n s( e s p e c i a l l yO b l i g a t e H y d r o g e n P r o d u c i n gA c e t o g e n s ,O H P A ) ,r e s p o n s i b l ef o rc o n v e r t i n gI - I P r a n d o t h e r h i g h e r V F A si n t o H A c ,C 02, a n dH2 .a r e i n h i b i t e di f t h eh y d r o g e n c o n c e n t r a t i o ne x c e e d s 0 . 0 1% .A s a r e s u l t , t h ee x c e s so fr e d u c t i o ne q u i v a l e n t si s d i v e r t e di n t ol e s sf a v o u r a b l eb i o c h e m i c a l r o u t e s ,r e s u l t i n g i n a c c u m u l a t i o no f H P r o rh i g h e rV F Ap r o d u c t s ( Z o e t e m e i j e r ,1 9 8 2 ) .T h i s o b s e r v a t i o nc a n p a r t l y e x p l a i n t h ef e a s i b i l i t yo f u s i n gt h e t w o - p h a s ec o n c e p t t os t a b i l i z ei n f l u e n t s u b s t r a t ea n a e r o b i c a l l y .H o w e v e r ,i fs y s t e mo v e r l o a d i n gs t i l l c o n t i n u e s ,h i g hc o n c e n t r a t i o no fV F A sw i l ld e s t r o yt h eM - U A S Bb u f f e r i n gc a p a c i t y ,r e s u l t i n gi na d r o p i nt h e d i g e s t e rp Ha n dd i s c o u r a g i n gt h e g r o w t ho f m e t h a n o g e n s .T h i s s i t u a t i o nc o m b i n e dw i t hh i g hl o a d i n g a n dh i g h r e c y c l er a t e sc a n l e a dt o aw a s h o u to f t h e m e t h a n o g e n sf r o mt h e s y s t e m . I ft h eH R Te x c e e d st h em a x i m u mb a c t e r i a lg r o w t hr a t e , c e s s a t i o no fC H4p r o d u c t i o na n df i n a l l y p r o c e s sf a i l u r em a yr e s u l t .D i f f e r e n ta p p r o a c h e sa n d m e t h o d sh a v eb e e np r o p o s e dt o p r e d i c tw h e t h e rt h es y s t e mh a s f a i l e do r n o t .G r a e f a n dA n d r e w( 1 9 7 4 aa n d1 9 7 4 b )s u g g e s t e dt h a t c e s s a t i o no f C H4p r o d u c t i o nr a t e , s u d d e ni n c r e a s ei nV F Ac o n c e n t r a t i o n ,ai n c r e a s ei n % C O2c o n t e n ti nd r yg a s , a n da d r o pi n p H ,a s i n d i c a t o r so fp r o c e s sf a i l u r e .M o r e o v e r ,B e r g m a n( 1 9 6 6 )p r o p o s e dt h a tt h er a t i oo fV F A l a l k a l i n i t ye x c e e d i n g0 . 3 - 0 . 4 w a sa s i g n a lf o rp r o c e s sf a i l u r e .8 5A ss h o w n i n F i g u r e5 . 1 1 a n dF i g u r e5 . 1 3 - 5 . 1 4 ,t h e s y s t e m ( M - U A S B ) ,d u r i n gt h em a x i m i z a t i o ns e q u e n c e ,i n d i c a t e ds o m es i g n so ff a i l u r ea s t h el o a d i n g r a t e i n c r e a s e d ,b ys h o r t e n i n gt h e H R T f r o m 3 . 4 0t o1 . 2 0d a y s ;i tf a i l e dc o m p l e t e l ya t a nH R To fl e s s t h a n1 . 0 d a y( 0 . 9 8 ) , e q u i v a l e n tt o as y s t e m h y d r a u l i cl o a d i n go f 1 . 0m3/m-d. C O D ( s o l . ) a n dV F A r e m o v a le f f i c i e n c i e sd e c l i n e df r o m9 0%d o w nt ol e s s t h a n1 0% ,a t t h eH R To f1 d a y , w i t ha c c u m u l a t i o no f P04-P i n s i d e t h es y s t e m ( a s s h o w ni nF i g u r e5 . 1 1 ) . F i g u r e5 . 1 3 c o n f i r m st h i s s i t u a t i o n ,w h e r e b y t h et o t a l V F A c o n c e n t r a t i o nr o s ei nt h er e a c t o r a td a y3 7 ,a ta s y s t e mh y d r a u l i c l o a d i n gr a t e o f0 . 3 5m3/m-d.I n i t i a l l y ,t h ec o n c e n t r a t i o no fb o t h H A ca n dH P ri n c r e a s e dr a p i d l yt o9 3 0m g / La n d3 4 0m g / La td a y 4 0 ;a p p r o x i m a t e l y3 - 4d a y sl a t e r ,t h e1 - l A c d i s a p p e a r e da n d t o t a lV F Ac o n c e n t r a t i o nr o s e t o1 8 0 0 m g / L a sH A c ,b yd a y4 2 .A l s o ,t h ep r e s e n c eo fH B u a n do t h e rh i g h e rV F A Sw a s n o t e d ,f u r t h e ri n c r e a s i n gt h ec o n c e n t r a t i o no f t o t a lV F Au pt o 2 8 1 5 m g / La s H A ca ta nH R To f 1 d a y( o r p r o c e s sf a i l u r e ) .I t i si n t e r e s t i n g t on o t et h a t t h e r ei s a na c c u m u l a t i o no f H P ra ta nH R To f l e s s t h a no n ed a y . U n d e rt h es t r e s s o f ah i g h o r g a n i cl o a d i n gr a t e , t h e r e m a yb ea s h i f ti n t h em e t a b o l i cp a t h w a yt o al e s sf a v o u r a b l eo n e ,i n s i d et h e r e a c t o r . A st h eMU A S Bw a sl o a d e du ps t e p - b y - s t e p ,t h e r ew a sa s h i f ti n t h er a t i oo fV F Ap r o d u c e r s( a c i d o g e n sa n d a c e t o g e n s )a n dc o n s u m e r s( m e t h a n o g e n s ,S R B ,a n dN R B )i n s i d et h er e a c t o r .T h i sl e a d st ot h ep r o d u c t i o no f s i g n i f i c a n ta m o u n t so f C O2a n d H2. A sa r e s u l t ,t h ep a r t i a lp r e s s u r eo f H2 i n s i d et h es y s t e mi n c r e a s e su pt o c e r t a i nl e v e l(h i g h e rt h a n1 0a t m)c a u s i n gas h i f ti n t h e m e t a b o l i cp a t h w a ya n da c c u m u l a t i o no fH P r ,a s s h o w ni n F i g u r e5 . 1 2 .A sa l s os h o w ni n F i g u r e5 . 1 3( a ) ,t h ee f f l u e n ts o l u b l eC O Da n dV F Ac o n c e n t r a t i o n si n c r e a s e dg r a d u a l l yt od a y 5 1 ,w i t ha ni n c r e a s ei nl o a d i n gr a t e , a f t e r8 6F i g u r e 5 . 1 1 AT w o - p h a s e ( U A S B - U A S B )S t e p - l o a d i n gA n dM - U A S B R e m o v a lE f f i c i e n c yD u r i n gt h e s y s t e mm a x i m i z a t i o n( a )H R T , K gC O D / c u m - d ;( b )R e m o v a le f f i c i e n c y2 4 -2 0 -1 6 -1 2 -8- K g C O D ! c u . m - d2 5 4 7 6 a1 0 2] 1 M E ,d a y sa8I401 0 08 06 04 02 00- 2 05 1— II I— ‘ III’I.1 81 11 52 2 2 7 3 33 74 2 4 7l i M Ed a y s- _\ \ , 4 / ’• C O D( R I . )+ P 0 4 - P- 4 0 -- 6 0 -- 8 0161 11 5 2 22 7 3 33 7 4 24 7l i m e ,d a y s5 187(1) C9 2 NA&+ 2ADP + 2 p — 2 CHOOOH + 2 NADH + 2ATPPynMc add(2) 2 NADH —2 NAD . 2 H2 (2) CH OCOOH + 2 NADH + ADP + P(3)2 CH SOCOOH +2 NAD—CCI-COOH +2 NAD+ ATP +2 CKoA + 2 C+ 2 NACH (3) CHOCOOH + NAD(4)2CHoA+2ADP+2P—CCoA+O2+NADH2CHOOH+2ATP (4)CHoA+NADHCOOH+H+NAD(I) Gft.jcose (1 Glucose;NA1;7.r_aLa,I___2’ I2*0.(SI• I) 2*?’ (3g.. IMPc3 2PYR 2PYR(.32: I c 2>CA) 2AcCoA t AcC0A !‘H?r - HO(5’.. 3)12NAc ‘ HAc Ic.toc.C Aç•r;CSIc;. Ste;.SIc;.1 cr1ict pr.ssur. () ;ç;-I ‘4a c’aI r•S%if•Overail: C2&.2H2+4ADP+4P %J+3AOP+3P2CHOOH+2CO +4H24ATP CCCOOH+CCOOH+c ++3ATPFigure 5/2Aciaogenic phase ofglucosefermentation under low andh:ghH2partidpressures to form acetic acid propionic acid ‘‘2 gas and CO2.(Abbreviations: EM? - Embden-Meyerhof pathway; PYR - pyruvicacid; AcCoA — acetyl coenzyme A; I-fPr — propionic acid; HAc — acetic(Source: Modified after PALNS et.aI, 1987)14768102 —/ 1T i m e , d a y s11 12 23 34 2 5 1T I m e , d a y s— 1- 0 . 8- 0 . 4-0 . 208 8• C H 4 , V d÷ % C 0 2C O D( a )I2 6 02 4 02 2 02 0 01 8 01 6 0 -1 4 0 -1 2 0 -1 0 0 -8 0 -6 0 -4 0 -2 007---..-I’ll I”II1 0 -9 —6 -85 - •4 j2 — i04 -3 . 5-32 . 50 . 5M a 2 d n , nl o a d sU>4 -3 . 5 -3 -2 . 5 -2 -1 . 5 -1 —0 . 5 -0 .- 1 . 8- 1 . 41 . 22 54 76 6T i m e , d a y sDV F N A L K• T o t . V F A— H A C1 0 2( b )0 . 8161 1 1 52 22 73 33 7 4 24 75 1T I m e , d a y sF i g u r e5 . 1 3A M - U A S BS y s t e mE f f l u e n tQ u a l i t i e s :D u r i n gt h e p r o c e s sm a x i m i z a t i o n( a )C H 4p r o d u c t l o n , % C 0 2 , E f f . C O D ; ( b )T o t a lV F A , H A c / H P r , V F A / A l k a l l n I t y891 0.ooyp.flod9IE f f l u e n t MLV+ M L V S S ( M . U A S B )87A1 2 5 47: 6 8 1 0 2l i m e ,d a y s(a)0•I161 1 1 5 2 22 73 33 74 2 4 7 5 1l i m e ,d a y sT 1 < N ( M - I J A S 8 )U i d n i t m ,t o a d ’R . o o . t y o e d o d0 . 9_____T P ( M - U A S B )-(b)1I0 . 6l i m e ,d a y sitfttaftftftrl i m e ,d a y sFigure 5.14 A M-UASB Nutrients and MLVSS:During the System Maximization(a) Effluent MLVSS,MLVSS(M-UASB); (b) TKNJP9 0s h o r t e n i n gt h e H R T ( M - U A S B )t o 1 . 2 0d a y s . T h eC O2 c o n t e n ti n t h eo f f g a si n c r e a s e df r o m a p p r o x i m a t e l y3 1 . 0 3 ( d a y 3 7 )t o 5 1 %( d a y5 1 ) ,a st h e l o a d i n gr a t ei n c r e a s e d ,w h i l eC H4 g a sp r o d u c t i o ni n c r e a s e da l m o s tl i n e a r l yw i t had e c r e a s ei n H R T ( M - U A S B ) d o w nt o 1 . 5 5d a y s ; h o w e v e r ,b e y o n dt h a t ,t h e C H4 p r o d u c t i o nr a t e d e c r e a s e d w i t ha d e c r e a s ei n H R T . T h eV F A / a l k a l i n i t yr a t i oa l s os h o w e de v i d e n c e o f s y s t e mf a i l u r e a ta n H R Tl o w e r t h a n1 . 5 5 d a y s . T h er a t i os e e m st o i n c r e a s el i n e a r l yw i t had e c r e a s i n g H R Ta n di s a b o v et h e c r i t i c a ll e v e l o f 0 . 3 - 0 . 4 r e c o m m e n d e db yB e r g m a n( 1 9 6 6 ) .T h ew a s h o u tp h e n o m e n o n( a ss h o w ni n F i g u r e 5 . 1 4 ) ,l e a d i n gt os y s t e mf a i l u r e ,c o r r e s p o n d e dt o a ni n c r e a s ei n e f f l u e n tV S Sf r o m t h es y s t e m .T h ec o n c e n t r a t i o np r o f i l eo fM L V S Si nt h e M - U A S B ,a ss h o w ni n F i g u r e5 . 1 4 ,i s s i m i l a rt ot h a to f C R4g a sp r o d u c t i o n ,i l l u s t r a t e d i nF i g u r e5 . 1 3 .A s s h o w n ,t h es y s t e mb e g a nt ow a s ho u t t h eM L V S Sa n d t h ec o n c e n t r a t i o no fM L V S Si n t h e r e a c t o rd e c l i n e ds h a r p l ya f t e rr e a c h i n ga nH R T ( M - U A S B )o f1 . 5 5d a y s ;h o w e v e r ,t h eM L V S Sc o n c e n t r a t i o nd i dr e c o v e rs l i g h t l ya f t e r a b o u t4 d a y s ,a t ah y d r a u l i cl o a d i n gr a t eo f1 . 8 0m3/m-d ( H R T o f 1 . 0 d a y ) . T h i ss i t u a t i o nm a yh a v er e s u l t e df r o mt o o h i g ha l o a d i n gr a t ec r e a t i n ga nu n s e t t l e ds i t u a t i o na n ds e v e r et u r b u l e n c ei nt h e l o w e rp a r to f t h er e a c t o r ,t h u sp a r t l yd e s t r o y i n gt h es l u d g eb e d . B e c a u s et h es a m p l e sw e r et a k e ni nt h em i d d l eo ft h er e a c t o r( S a m p l i n gp o i n tn o . 6 ) ,i ti s p o s s i b l et h a tah i g h e rc o n c e n t r a t i o no fM L V S S ,r e s u l t i n gf r o mt h i st u r b u l e n c ei nt h i sp a r t i c u l a rc a s e ,c o u l do c c u r .I t i si n t e r e s t i n ga tt h i s p o i n tt on o t e t h a tt h em a i nc a u s e so f p r o c e s sf a i l u r ew e r et h e c o m b i n a t i o no f h y d r a u l i co v e r l o a d i n g ,t h u se x c e e d i n gt h eg r o w t hr a t eo fb o t h9 1a c i d o g e n sa n dm e t h a n o g e n s ( w a s h o u tp h e n o m e n o n ) , a n dt h e d e s t r u c t i o n o f t h ed y n a m i cb a l a n c eo fa c e t o g e n sa n dm e t h a n o g e n s i n s i d e t h e M - U A S B .T h es y s t e md e m o n s t r a t e da ni n c r e a s e i n V F Ac o n c e n t r a t i o na n d%C O2 c o n t e n t , b u t a d e c r e a s e i n%C H4 c o n t e n ta n d p r o d u c t i o n ,a sd i s c u s s e de a r l i e r .T h i s o b s e r v a t i o n a l s oc o n f i r m e dt h a tt h e f a i l u r e w a sn o t c a u s e db y a t o x i c e f f e c t ,s i n c e t h e r e w a s n o s i g no f a d e c r e a s ei nV F Ac o n c e n t r a t i o nc o r r e s p o n d i n gt o ad e c r e a s e i n%C H4 c o n t e n t .I n t e r m o f n u t r i e n tr e q u i r e m e n t sd u r i n gt h ep r o c e s sf a i l u r e , o n l y t h ec o n c e n t r a t i o no fT P i n s i d e t h er e a c t o ra n d e f f l u e n ti n c r e a s e ds i g n i f i c a n t l y ;T K Ni n c r e a s e do n l y s l i g h t l y .( b )M a x i m u mL o a d i n gR a t eT h es y s t e m c o m p l e t e l yf a i l e da st h el o a d i n gr a t ew a si n c r e a s e da n d t h eH R T w a ss h o r t e n e d ,i ns t e p w i s ef a s h i o n . A ss h o w n i nF i g u r e5 . 1 5 , t h es o l u b l eC O D r e m o v a le f f i c i e n c yd e c l i n e dl i n e a r l y ,a s t h e H R Td e c r e a s e db e y o n d1 . 5d a y s .T op r e d i c t t h em a x i m u ml o a d i n gr a t ep r e c i s e l y ,a s i m p l e l i n e a r r e g r e s s i o nw a sa p p l i e d ,u s i n gt h e a v e r a g ev a l u e so f e a c hs t e pl o a d i n gr a t e ,a t p s e u d os t e a d y - s t a t ec o n d i t i o n sa sf o l l o w s :Y= 1 2 9 . 2 8 1- 3 . 2 1 4 X( 1 5 )w h e r eY =%C O D( s o l u b l e )r e m o v a le f f i c i e n c yX= I n f l u e n tf l o wr a t e ,L i d0 . 8 89 21 0 0-9 0 -8 0 -7 0 -60-5 0-4 0 -3 0 -2 0 -1 00( a )Y = 1 2 9 . 2 8 1- 3 . 2 1 4 Xy= %C O D R e m o v a lE f f i c i e n c yx = I n f l u e n tF l o w R a t e ,l / dr2= 0 . 8 8M a x . S y s t e mC a p a c i t y= 4 0l / dO p e r a t i n g C o n d i t i o n s ;S R8 0 / 2 0 , R R 5 / 8T e m p .3’CN op H C o n t r o l+ % C O D R e m . E f f .• I n f l u e n t F l o w , l / dC r i t i c a lH R T s y s , d = 3 . 0H R T m - u a s b= 1 . 5- 1 0 0- 9 0- 8 0- 7 0-60• 5 0L .-40- 3 0- 2 0- 1 00a )C . )Ea )0C )C0D- o00 .IC )0a )- C01 0 09 08 07 06 05 04 03 02 01 00—IIIIII—0 . 51 . 52 . 53 . 54 . 5M - U A S BH R T ,d a y s( b )./S y s t e mH R T%T h e oC H 4P r o d[ . . : ‘ : . . . : . . . ‘ . : . 1 . 7 7 3 6 . 4 7I ...::.:...::.:. 2 . 1 8 6 0 . 1 1/ 2 . 8 0 7 3 . 2 1I ..::...-...:::.: 4 . 8 0 9 7 . 9 9I 6 . 0 7 8 3 . 7 0L_J O p t i m a l O p e r a t i n g R e g i o n—IIII1234567S y s t e mH R T ,d a y sFigure 5.15 System Optimum Operating Region and Maximum Capacity:( a )O p t i m a lO p e r a t i n gR e g i o n ; ( b )T h e o r e t i c a lC H 4P r o d u c t i o n9 3B a s e do n t h i ss i m p l em o d e l ,t h em a x i m u ml o a d i n g r a t e ( d e f i n e da sn o C O Dr e m o v a le f f i c i e n c y )a ss h o w ni n F i g u r e 5 . 1 5 , w a sa b o u t4 0L I d ; t h i sw a se q u i v a l e n tt o as y s t e m h y d r a u l i cl o a d i n g o f 1 . 8 0m3/m-d, a t a s y s t e m H R T o f 1 . 1 2 5 d a y s(0 . 6 2 5d a y f o rM - U A S B) .T h eC H4 g a s p r o d u c t i o na tt h i s p o i n to fc o m p l e t ef a i l u r ew a s a b o u t5 0%o ft h e t h e o r e t i c a lv a l u e ,w h i c hi s ac o m b i n a t i o no f C H4 g a s p r o d u c t i o nf r o m b o t h A -a n dM - U A S B s .D e t a i l s o fc a l c u l a t i n gt h e t h e o r e t i c a lC H4 g a sp r o d u c t i o n( b a s e do n t h ea s s u m p t i o nt h a t t h e i n f l u e n ts u b s t r a t ei s 1 0 0%g l u c o s e ) ,a r e s h o w ni nT a b l e D 3 . 1o fA p p e n d i xD .A t t h i s“ f a i l u r el o a d i n g ” ,t h e e f f l u e n tC O D( s o l . )w a si ne x c e s s o f9 5 4 0m g / L , t o t a lV F A sw e r ea b o v e3 , 7 5 0m g / La sH A c , t h eC O2c o n t e n tw a sm o r et h a n 4 5% , a n dt h eV F A l a l k a l i n i t yr a t i ow a so v e r1 . 5 5 .O l e s z k i e w i c z( 1 9 8 8 )i n d i c a t e dt h a tt h e“ f a i l u r el o a d i n gr a t e ”f o r ab i o f i l t e ru s i n g aU A S Br e a c t o rt os t a b i l i z e s y n t h e t i cw a s t e w a t e r ,w a s2 0 k g COD/m3-d, w h i c h i s e q u i v a l e n t t o 5 0L I da ta nH R To f5 . 8 h r s .M o r e o v e r ,B e r g m a n( 1 9 6 6 )p o i n t e do u tt h a t h i s s y s t e m ,b e i n gu s e dt o t r e a ts e w a g es l u d g e ,f a i l e da ta nH R To f2 . 2 0 d a y s ,a p H o f4 . 6 0 ,a n daH A c : H P r : H B ur a t i oo f2 . 0 : 2 . 5 : 1 . 0 ,w i t hH P ro v e r9 , 0 0 0m g / L .A l t h o u g ht h e s er e s u l t sa r en o td i r e c t l y c o m p a r a b l e ,t h e r ei ss o m es i m i l a r i t yi nt h ed a t a b a s e sf r o mt h e s eU A S B - U A S Bs t u d i e s ,w i t hr e c o g n i z a b l ep a t t e r n sa n d n u m e r i c a li n d i c e si nt h es a m eg e n e r a lr a n g e .5 . 2 . 2 . 2R e c o v e r yP r o c e s sI n a n a e r o b i ct r e a t m e n tp r o c e s s e s ,s h o r tt e r mh y d r a u l i co v e r l o a d i n gi sap r o b l e md i f f i c u l tt o a v o i da n d o p e r a t i o n a lf a i l u r ei s f r e q u e n t l yt h eo u t c o m e .A ne x t e n d e dr e a c t o r9 4r e c o v e i yp e r i o di s u s u a l l yn e c e s s a r y . T h ep r o b l e mo f h y d r a u l i co v e r l o a d i n gi s a g g r a v a t e dw h e r en o r e c y c l ef a c i l i t y i sa v a i l a b l e ,t op r e v e n tt h el o s s o ft h es l o w g r o w i n gm e t h a n o g e n sf r o m t h es y s t e m . T h ef o l l o w i n gs e c t i o n s d e a lw i t ht h eb e h a v i o u ra n dr e s p o n s eo f t h i ss y s t e ma f t e r c o m p l e t ef a i l u r e a n d t h er e c o v e r yt o i n i t i a ln o r m a l i t y .P r i o rt o a d e t a i l e dd i s c u s s i o n ,h o w e v e r ,s o m e c l a r i f i c a t i o n ss h o u l db e m a d e .T h et e r m “ p r o c e s sf a i l u r e ” c a n b e e i t h e rt e m p o r a r y(i e . a s u d d e n o r g a n i cs h o c kl o a d i n g) o r r e l a t i v e l yp r o l o n g e d ( i e .at o x i cs h o c k l o a do r h y d r a u l i c o v e r l o a d i n g-c o m p l e t ew a s h o u to ft h e a c t i v eb i o m a s s ) .S e v e r a ls t u d i e sh a v ed e a l tw i t h t e m p o r a r yf a i l u r e s ,b u tr a r e l yw i t ha p e r m a n e n to n e ,e s p e c i a l l yt h a to fh y d r a u l i co v e r l o a d i n g .T h ef o l l o w i n gs e c t i o n sd e a l w i t hs y s t e m r e c o v e r yb a c k t ot h e i n i t i a ls t a g e , u s i n ga c o m b i n a t i o no fR Ra n ds t e p - d o w nl o a d i n ga p p r o a c h e s .( a ) R e c o v e r yP e r i o dT h ew o r s ts c e n a r i o i nr e c o v e r i n gas y s t e ma f t e rc o m p l e t ef a i l u r ei st h e n e e dt or e - s e e da n dr e - a c c l i m a t i z et h es y s t e m .H o w e v e r ,t h i so p t i o ni s c o s t l ya n dn o t p r a c t i c a li nt e r m so faf u l l - s c a l eo p e r a t i o n :t i m e - c o n s u m i n gp r o c e s s e sa n dh i g h - s k i l l e dm a n p o w e ra r er e q u i r e d .A c o m b i n a t i o no f s t e p - d o w nl o a d i n gr a t ea n dR Ri s r e l a t i v e l ys i m p l ea n d q u i t ep r a c t i c a l ,c o m p a r e dw i t ht h eo p t i o no f r e s e e d i n ga n d a c c l i m a t i z a t i o n( s t e p - u pl o a d i n g ) .H o w e v e r ,s o m eq u e s t i o n ss t i l le x i s t a st ow h e t h e rt h i s a p p r o a c hi s m o r ee f f e c t i v et h a nt h a to fr e - a c c l i m a t i z a t i o n ,a n dw h a tc h a n g e st h es y s t e mu n d e r g o e sd u r i n gt h er e c o v e r yp r o c e s s ,c o m p a r e dw i t ht h a t o ft h e i n i t i a ln o r m a ls t a g e .9 5A ss h o w ni n F i g u r e 5 . 1 6 - 5 . 1 8 ,t h e s y s t e m a p p e a r e dt ob e g i nr e c o v e r i n g f r o m t h es e r i o u sf a i l u r e a f t e r 1 9d a y s o f d e c r e a s i n gt h e h y d r a u l i cl o a d i n g f r o m0 . 4 0t o0 . 2 5m31m-d ; t h i s w a sa c c o m p l i s h e db y p r o l o n g i n gt h eH R T ( M - U A S B )f r o m1 . 2 0d a y u p t o2 . 0 0d a y s .T h e s y s t e m d e m o n s t r a t e dC O D a n dV F A r e m o v a le f f i c i e n c i e s( M - U A S B )o f 4 3a n d4 5%r e s p e c t i v e l y ,w i t h6 , 5 8 0m g / L e f f l u e n t C O D ,4 7%C O2 c o n t e n t , 6 8L I do f C H4g a sp r o d u c t i o n ,a n da V F A l a l k a l i n i t yr a t i o o f1 . 4 0 . T h e r e a f t e r ,t h e s y s t e m s e e m e d t or e c o v e rl i n e a r l yw i t h t i m e a n dr e c o v e r e d c o m p l e t e l yt o t h ei n i t i a ll e v e l o f o p e r a t i o na ta p p r o x i m a t e l yd a y4 3 , t h e r e b ys h o w i n g9 7%V F A a n d9 2%s o l u b l eC O Dr e m o v a le f f i c i e n c i e s .T h ee f f l u e n tC O D ( s o l u b l e )w a s l e s st h a n1 , 0 0 0 ( 8 8 0 )m g / La n d t h e t o t a lV F Aw a s1 2 5 m g / La s H A c , w i t h3 2%C O2 c o n t e n t , 6 2L I do f C H4 g a s p r o d u c t i o n , a n dV F A l a l k a l i n i t yr a t i o o f l e s st h a n 0 . 1( 0 . 0 5 ) . T h es y s t e mt h e nf o l l o w e da“ d i m e n s i o n a lt i m ef r a m e ” ,d e f i n e da st h er a t i oo f t h er e c o v e r yt i m et o t h e H R T ;t h i sw a s e q u a l t oa p p r o x i m a t e l y5 . 6 0a n d 1 0f o rt h es y s t e ma n dt h e M - U A S B ,r e s p e c t i v e l y .T h i s c o m p a r e dw e l lt o a r a t i oo f5 - 1 0 f o ra n e x p a n d e db e da n a e r o b i cr e a c t o r(U A S Bw i t he f f l u e n tr e c y c l e) ,o p e r a t e da t ah i g h o r g a n i c l o a d i n gr a t e i n n o n - s t e a d ys t a t ec o n d i t i o n sr e p o r t e de l s e w h e r e( E n c i n a ,1 9 8 7 ) .B yd a y3 0 , t h ea c t i v eb i o m a s s( M L V S S )o ft h e s l u d g eb l a n k e t ,i nt h em i d d l eo ft h e r e a c t o r ,r e c o v e r e da n d r e a c h e da p e a ka t d a y4 0 . T h i sm a yh a v eb e e nt h e r e s u l to ft h es y s t e m b e g i n n i n gt or e c o v e ra n dp r o d u c i n gs m a l lg a s b u b b l e s ,t h u sc r e a t i n gf l o c c u l a t i o na tt h e s l u d g eb l a n k e t l e v e l ,( t h e r ew a s e v i d e n c eo f i n c r e a s i n gC H4g a sp r o d u c t i o na t d a y3 0 , a s i l l u s t r a t e di nF i g u r e 5 . 1 7( a ) ) . F o rt h en e x t1 0 d a y s( d a y 3 8 -4 3 ) , i ti s s p e c u l a t e dt h a tt h e g r a n u l a t i o np r o c e s sp l a y e dam a j o rr o l e i na s s i s t i n gs u b s t r a t es t a b i l i z a t i o na n d s y s t e mr e c o v e r y ;t h e r e w a sa s h a r pi n c r e a s ei nC O Da n dV F A9 62 2 -2 0 -1 8 -E -1 8-0-C . ,_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _1 4-1 2)10:8642 Ti’i’iii’ I1 51 01 51 92 6 3 84 55 1l i M E , d a y s2 :- 1 0- 3 0 -- 5 0 -- 7 0/VM a ) * n , . , nl o a d sR e c o w t yp . i o d1 2 54 7 6 81 0 2l i m e ,d a y s‘ 4 -l i m e , d a y s( a )• H R T+K g C O D / c u m - d11 01 9 3 85 1l i m e ,d a y sFigure 5.16 A Two-phase (UASB-UASB) Step-loadingAnd M-UASB Removal EfficiencyD u r i n gt h es y s t e mr e c o v e r y( a )H R T , K gC O D / c u . m - d ; ( b )R e m o v a le f f i c i e n c y9 71 9— 1 9 0- M a x i m u mL o a d s R e c o v e f y P e r i o d( a )•C H ,C O D% C O 22 5 4 76 81 0 2E 1 1— j1 1 0T l m e , d a y s-. ._ _ _. 1 0_ _ _ _ _:f l m e , d a y s68- \A e c w y p . 1 o d( b )V F N A L K• T o t . V F A3 5::H A c1 3 Z 2H P r12 5T i m e , d a y s320T i m e ,d a y sF i g u r e5 . 1 7 AM - U A S BS y s t e mR e c o v e r y P r o c e s s :( a ) C H 4 p r o d u c t i o n , % C 0 2 , E f f . C O D ;( b )T o t a lV F A , H A c / H P r , V F N A k a l i n i t y9 88 -( a )M s j d , m a i l o a d sE f f l u e n t M L V S S:M L V S S( M . I J A S B )1 7 1T I M E , d a y sT i m e , d a y s1 . 2( b )1 . 1T K N ( M - U A S B )M a d m u m l o a d s P o c o v e r y p o t o d1T P ( M - U A S B )•E f f l u e n tT K N i - E f f l u e n t T P0 . 90 . 812 54 76 81 0 20 . 7T I M E , d a y sE0 . 80 . 50 . 40 . 30 . 20 . 10I I1 1 0 1 93 85 1l i M E ,d a y sF i g u r e 5 . 1 8 A S y s t e mN u t r i e n t s a n dM L V S S :D u r i n g t h er e c o v e r y p r o c e s s( a )E f f l u e n tM L V S S , M L V S S ( M - U A S B ) ;( b )T K N , T P9 9r e m o v a le f f i c i e n c i e s , a p p r o x i m a t e l y9 1 - 9 7 % ,a V F A / a l k a l i n i t yr a t i ol e s st h a n 0 . 5 , a n das h a r p b u i l du p i nb i o m a s s ( M L V S S )i n t h es l u d g eb l a n k e t ,u p t o 1 , 7 0 0 m g / L .N u t r i e n tr e q u i r e m e n t s ,m e a s u r e da s C O D( t o t a l ) : T K N : T Pi n s i d e t h e r e a c t o ra t t h e s l u d g e b l a n k e tl e v e l( s a m p l i n gp o i n t n o . 6 ) , w a si n t h e r a t i o o f 3 6 : 4 : 1 .( b ) S y s t e mR e c o v e r yA l t h o u g h t h e s y s t e mr e t u r n e dt o t h ei n i t i a ll e v e lo f o p e r a t i o nb y d a y4 0 , i t i sq u i t ei n t e r e s t i n gt o n o t et h a ta na c c u m u l a t i o no fH P ra n d a n i n c r e a s ei nt o t a l V F Ao f t h e MU A S Bo c c u r r e d ,a ss h o w ni nF i g u r e 1 7( b ) ;t h i s i s i n a g r e e m e n tw i t h r e s u l t sr e p o r t e db yZ o e t e m e i j e re t a l , ( 1 9 8 2 ) . T h i sm i g h ts u g g e s t t h a tt h es y s t e mm e t a b o l i cp a t h w a y ss h i f t e dt oa l e s s f a v o u r a b l er o u t e ; h o w e v e r ,t h ep a t h w a y sd i ds h i f tb a c k t om o r ef a v o u r a b l eo n e sa f t e ra l m o s t2 0 d a y so f l o a d i n g r e d u c t i o n ,a sa ni n c r e a s e i n C H4g a s p r o d u c t i o n ,%C Hc o n t e n t ,a n dal i n e a r r e d u c t i o no f T o t a lV F Aa n dH P rc o n c e n t r a t i o nw e r eo b t a i n e d .R i n z e m a( 1 9 8 8 )i n d i c a t e dt h a t a s y s t e m u s i n gt h eU A S Bp r o c e s s ,i n o c u l a t e dw i t hg r a n u l a rs l u d g et os t a b i l i z eV F Ai n t h ep r e s e n c eo fH2S c o n c e n t r a t i o no v e r1 0 0 m g / LS ,h a das h a r pd r o po fV F Ar e m o v a l e f f i c i e n c y ,b u tr e c o v e r e dw i t h i n3 - 4 w e e k s .T od e m o n s t r a t eh o ww e l lt h e s y s t e mr e c o v e r e da te a c h s t e po f l o a d i n gr e d u c t i o n ,c o m p a r e dw i t ht h es a m e l o a d i n gr a t ed u r i n gt h e m a x i m i z a t i o np r o c e s s ,s o m em o d i f i c a t i o na n df u r t h e ra n a l y s i so f t h e e x p e r i m e n t a lr e s u l t s w e r em a d e ,a ss h o w ni nF i g u r e 5 . 1 9a n d5 . 2 0 .C O D( s o l . ) r e m o v a le f f i c i e n c ya n d C H4g a sp r o d u c t i o nw e r e s e l e c t e da s m a i nr e s p o n s ep a r a m e t e r sf o r t h i si n v e s t i g a t i o n ,s i n c es u p e r i o rs u p e r n a t a n tq u a l i t ya n d1 0 0r e a s o n a b l eC H4g a sp r o d u c t i o na r et h e t w o m a i n o b j e c t i v e so ft h ea n a e r o b i cs t a b i l i z a t i o np r o c e s s .F i g u r e s 5 . 1 9 ( c ) a n d5 . 1 9( d )s h o wt h e r e l a t i o n s h i pb e t w e e n t h e a c t u a lr u n n i n gH R T a n d% s o l u b l eC O Dr e m o v a l e f f i c i e n c y d u r i n gt h e m a x i m u m l o a d i n ga n d r e c o v e r yp e r i o d .B a s e do nt h e s e r e l a t i o n s h i p s ,C O D r e m o v a l e f f i c i e n c ya te a c hd i s c r e t e H R Ts t a r t i n gf r o m1 , 1 . 5 , . . . 4 . 5 d a y sc a nb ee s t i m a t e d d u r i n gt h e m a x i m i z a t i o n a n dr e c o v e r yp e r i o d .S y s t e mr e c o v e r y e f f i c i e n c y ,d e f i n e da s a p e r c e n t a g eo f C O Dr e m o v e dd u r i n g t h er e c o v e r yp e r i o d o v e r t h a t o f m a x i m i z a t i o na tt h es a m e H R T ,c a n t h e nb e c a l c u l a t e da n dg r a p h e d ,a s s h o w n i nF i g u r e s5 . 1 9 ( a )a n d 5 . 1 9( b ) . S i m i l a r l y ,s y s t e m r e c o v e r ye f f i c i e n c yi nt e r m so f C H4g a s p r o d u c t i o na t e a c hs p e c i f i cH R Td u r i n gt h e m a x i m i z a t i o na n dr e c o v e r yp e r i o dc a na l s ob e e x p r e s s e d ,a ss h o w ni n F i g u r e s5 . 2 0( a )-5 . 2 0 ( d ) .P r e d i c t i v e m o d e l s f o rt h i ss y s t e mr e c o v e r y ,w i t ha h i g hc o r r e l a t i o n(r2= O . 8 1 - 0 . 9 9 ) ,a s s h o w ni nF i g u r e5 . 2 1 ,a r ef o r m u l a t e da sf o l l o w s :Y = 2 5 . 3 7 e°( 1 6 )w h e r eY= %C O D( s o l . )r e m o v a le f f i c i e n c yXH R T( M - U A S B ) ,d a y sF o r t h eC H4 g a s p r o d u c t i o n ,t h ep r e d i c t i v em o d e li s a sf o l l o w s :Y l= 9 . 2 5+ 6 4 . 0 1 l nX l( 2 0 )w h e r e Y l= C H4g a s p r o d u c t i o n ,L i d80> 0 E a: 400 C) 0 020I__i—___j:::::IIII.7—80.4)0:—:IIIIII.7,•.600O1rrrPI404)02000--flecovetyPeriod0041.rr,Ir..-.U00lOt)204)0044)05.00IUF.tloysFigure5.19AM-UASBSystemRecoveryatPseudoSteady-stateWithdifferentrunningconditions%COD(FIL)removal100(a)(b)IIRT.days%000(11.)removalMax.LoadsHecoveryPeriod%Hecover1.0221801.58837412.09540422.59750523.09760623.59871724.098°81834.598.90924.798.9698Note°Estimatedvalues100/801’.60f‘%Recovery40RecoveryPeriod20/•MadmurnLoadsaIIIII01.01.52.02.53.03.54.4.54.7FIIT.days100001--’”---r—:(c)160001:60.00:I!•IIILi..•40.00:IMaximumLoadso•IlIo:IIII2O.OoI ::IIIIII0.0004)00044)4)450204)2.0100350IIRI.JIlys(d)220•2.00C-)1.80Figure5.20AM-UASBSystemRecoveryatPseudoSteady-stateWithdifferentrunningconditionsCH4,cu.m/cu.m-d54.5•0 E3.5,E,2.5C)21s I.(a)•MaximtznLoads100C?%Recovery80 604.4...:+RecoveryPeriod152.02:53.5HRT, days2.6014.00—II:1(C)II!Eh1: MaximumLoadsioIIIIIIIIIIIIIIIIII‘.00,.nm’j.,...,,,.I3.000.501.00502.002.503003.0HRT.days(b)IJT.days.CH4,cu.m/cu.m.dMaxLoadsRecoveryPeriod%Recoveq12.452.4601.53.982.25572.03.651.88522.53.251.78553.02.551.76693.51.701.74102IIIIIIIIIIIIIIIIIII————4,::cij\RecoveryPeriodI40.‘,Irr,rf..I.-.--,-.-j-,-. .II,.3.oO1.002.003.C04.005.00HRT.das2401 0 3F i g u r e5 . 2 1 AP r e d i c t e d M - U A S B S y s t e mR e c o v e r yLU n d e r D i f f e r e n t R u n n i n g C o n d i t i o n s1 2 0 —%C O D ( E l i . ) r e m o v a l1 0 0C H 4 ,c m / c u . m - d /8 0 -( 2 )/G )>0C . )6 0 -.4 0, .( 1 )2 0 -O . 2 9 X( 1 ) Y = 2 5 . 3 7 e(r2= O . 9 9 )( 2 )Y = 9 . 2 5 + 6 4 . 0 1( m x ) ( r2 0 . 8 1 )0 -I II012345H R T ,d a y s1 0 4X l = H R T( M - U A S B ) ,d a y sT o m e e tt h e o b j e c t i v e so fb o t hp o l l u t i o nc o n t r o la n dm a x i m u m C H4 g a sp r o d u c t i o n ,t h e o p t i m u m s y s t e mH R To f7 . 6 5 d a y s a n d 4 . 2 5d a y sf o r t h e M - U A S B(e q u i v a l e n tt o 4 3 d a y so f r e c o v e r yp e r i o da f t e r c o m p l e t es y s t e m f a i l u r e)w e r e i n i t i a t e di n o r d e rt op r o v i d e9 2a n d 1 0 0%r e c o v e r yo f C O D r e m o v a l e f f i c i e n c ya n d C H4 g a sp r o d u c t i o n ,r e s p e c t i v e l y .I t i sa l s o i n t e r e s t i n g t o p o i n t o u tt h a t t h e b r e a k t h r o u g ho fs y s t e mr e c o v e r yi sp r e d i c t e da t a nH R T M U A S Bo f1 . 5 - 1 . 7 d a y s ,r e s u l t i n gi n m o r et h a n 4 0%r e c o v e r yo f b o t hC O D r e m o v a l e f f i c i e n c ya n dC H4g a sp r o d u c t i o n ,( a s s h o w n i nF i g u r e5 . 2 1 ) .T h e s y s t e m t h e n r e c o v e r e db a c kt o t h ei n i t i a l l e v e la t a nH R T o f 4 . 2 5d a y s .T h i so b s e r v a t i o n l e a d st o t h e c o n c l u s i o nt h a ta t w o - s t e pi n c r e a s ei nH R Tb y 1 . 5 0a n d5 . 8 0 t i m e st h a to ft h ef a i l u r e v a l u eH R T M U A S Bo f 0 . 6 2 5 d a y s , i s am o s te f f e c t i v em e a s u r ef o rc o m p l e t er e c o v e r y .5 . 2 . 2 . 3B a s i cE x p e r i m e n t a lK i n e t i c sS i n c et h e a n a e r o b i cs t a b i l i z a t i o np r o c e s si s c o n s i d e r e dt o b eb i - p h a s i ci nn a t u r e ,t h u sr e q u i r i n gab a l a n c eb e t w e e na c i dp r o d u c t i o na n d u t i l i z a t i o n ,p r o c e s ss t a b i l i z a t i o na n dc o n t r o lm a yb ep o s s i b l y e n h a n c e db yp h y s i c a ls e p a r a t i o no f t h e s et w op h a s e s .F i g u r e5 . 8 c o n f i r m e dt h ef e a s i b i l i t yo ft h e p h a s es e p a r a t i o nc o n c e p t ,a sd i s c u s s e de a r l i e r .A l t h o u g ht h es y s t e m a c h i e v e dp r o m i s i n gr e s u l t s ,i tw o u l db ei n t e r e s t i n gt o k n o wh o w t h em i x e d c u l t u r eo fb a c t e r i ar e s p o n d e dd u r i n gb o t ht h em a x i m i z a t i o na n d r e c o v e r yp e r i o d s .1 0 5O n e w a yt o a c h i e v e t h i s i s t o p r e d i c tt h e k i n e t i c r e s p o n s e g o v e r n i n gt h e a c i d - a n dm e t h a n e - p h a s er e a c t o r s( A - U A S Ba n dM - U A S B ) , u n d e rt h e s es i t u a t i o n s .T h i s p r e d i c t i o na n d e s t i m a t i o n w e r eb a s e d o n t h e e x p e r i m e n t a ld a t a o b t a i n e da tp s e u d os t e a d y - s t a t ec o n d i t i o n s ,w i t h ac o n t i n u o u ss t e p - l o a d i n gr a t e d u r i n g t h em a x i m i z a t i o na n dr e c o v e r yp e r i o d s .I t i si m p o r t a n ta t t h i sp o i n t t om e n t i o n t h a tt h i s k i n e t i ce s t i m a t i o ni ss y s t e md e p e n d e n t :p r o c e s s d e s i g n a n d c o n f i g u r a t i o n ,r u n n i n g c o n d i t i o n s , f e e dc h a r a c t e r i s t i c s ,s e e ds l u d g ea n ds t a r t - u pp r o c e d u r e ,a n de v a l u a t i o np r o c e s s .Ac o m p a r i s o no f t h e s ek i n e t i c v a l u e sw i t ho t h e r sm u s t i n d e e dt a k e t h i sd e p e n d e n c yi n t oa c c o u n t .T h eb a s i ck i n e t i c r e s p o n s e sp r e d i c t e dh e r e a r ee x p e c t e dt o b e h i g h e r t h a nt h o s ec i t e di nt h el i t e r a t u r e ,s i n c es y n t h e t i c s u b s t r a t ea n dc o n t i n u o u sf e e d i n g( i n s t e a do f b a t c h f e e d i n g )w e r eu s e d ,a l o n gw i t h ap r o l o n g e dp e r i o do fa c c l i m a t i z a t i o na n de x p e r i m e n t a lr u n n i n go fa w e l l - a d a p t e dm i x e dc u l t u r eo f b a c t e r i a .B e c a u s er e a c t o r k i n e t i c s g o v e r n i n gt h ea c i d p h a s ea n dm e t h a n ep h a s e a r e q u i t ed i f f e r e n t ,a s ab i - p h a s i cp h e n o m e n o n ,a ne s t i m a t i o no ft h ek i n e t i c sm u s tb e m a d ea c c o r d i n g l y .T h er a t e - l i m i t i n gs t e pi n t h eA - U A S Br e a c t o ri s t h eh y d r o l y s i so fp a r t i c u l a t ef e e d t os o l u b l es u b s t r a t e s ,w h i l e m e t h a n o g e n e s i si s t h ep r e d o m i n a n tp r o c e s si n t h eMU A S B .T h ef i r s t - o r d e rh y d r o l y s i sc o n s t a n t( K h ) a n dp e r c e n t a g eo fp a r t i c u l a t eh y d r o l y s i so f t h eA - U A S B ,t h e y i e l dc o e f f i c i e n t( a ) ,d e c a yc o e f f i c i e n t( b ) ,m a x i m u ms p e c i f i cs u b s t r a t eu t i l i z a t i o nr a t e( K ) ,a n dh a l f - v e l o c i t yc o e f f i c i e n t( K s )o ft h eM - U A S Bw e r ee s t i m a t e d ,i no r d e rt o p r o v i d ea b r o a dv i e wo f m i c r o b i a lr e s p o n s eu n d e rd i f f e r e n ts t r e s s e s .T h e h y d r o l y s i sr a t e( R h ) f o l l o w sa na p p r o x i m a t ef i r s to r d e r r e a c t i o n ,w i t hr e s p e c t1 0 6t ot h e c o n c e n t r a t i o no fd e g r a d a b l ep a r t i c u l a t eC O D ( P a v l o s t a t h i s , 1 9 8 6 ) .R h = K h * F( 1 7 )w h e r eR h= h y d r o l y s i sr a t eK h= f i r s t - o r d e rh y d r o l y s i s c o n s t a n tF = p a r t i c u l a t e C O Dc o n c e n t r a t i o nAM a s sb a l a n c ea r o u n dA - U A S Ba t s t e a d y - s t a t ec o n d i t i o n sy i e l d s :Q ( F o F ) V * K h * F= 0( 1 8 )w h e r e 0 = F l o w r a t eF o= I n f l u e n tp a r t i c u l a t eC O Dc o n c e n t r a t i o nV R e a c t o rv o l u m eD i v i d i n ge q u a t i o n( 2 2 )b yQa n d r e a r r a n g i n g y i e l d s :0= F o / ( F / 0 )-1 / K h( 1 8 )w h e r e0=H R T=V / Q ,F = F o - F , a n d F * K h=B y p l o t t i n g0a g a i n s t0 / S F ,t h e i n t e r c e p to ft h i sl i n ei s e q u a lt ol I K h ,a s1 0 7i l l u s t r a t e di n F i g u r e 5 . 2 2 ( c ) ; t h ev a l u eo f K hi s e q u a l t o 1 . 6 7d a y1( r2= 0 . 8 8 ) d u r i n g t h em a x i m i z a t i o np r o c e s s , c o m p a r e dw i t h3 . 0d a y1 r e p o r t e db y E a s t m a n ( 1 9 8 1 ) . R a j a n( 1 9 8 9 )a l s o r e p o r t e dt h a tt h e p e r c e n t a g eo fp a r t i c u l a t eh y d r o l y s i s w a s a b o u t4 5% , d e f i n e d a st h ep e r c e n t a g eo fe f f l u e n t s o l u b l eC O Do v e r t o t a lC O D . H o w e v e r , i n t h i s e v a l u a t i o n ,t h ed i f f e r e n c eb e t w e e nt h e e f f l u e n ta n d i n f l u e n t s o l u b l eC O D w a s u s e d t o c a l c u l a t et h ep e r c e n t a g eo f p a r t i c u l a t eh y d r o l y s i su n d e rd i f f e r e n tl o a d i n g c o n d i t i o n s ,a s s h o w n i nF i g u r e5 . 2 2( d ) .T h er e l a t i o n s h i p b e t w e e nt h e r a t eo fm i c r o b i a lu t i l i z a t i o no ft h e s u b s t r a t ea n dt h er a t eo f b a c t e r i a l g r o w t hc a nb ee x p r e s s e d i nt e r m so f am a t h e m a t i c a lm o d e ld e v e l o p e db yL a w r e n c ea n dM c C a r t y( 1 9 7 0 ) :6 S / &= a 6 L / 6 t- b S( 1 9 )w h e r e6 S / 6 t= n e t g r o w t hr a t eo fm i c r o o r g a n i s m s ,m a s s / v o l - t i m ea=g r o w t h y i e l dc o e f f i c i e n t ,m a s s / m a s s6 L / 6 t = s u b s t r a t eu t i l i z a t i o nr a t e ,m a s s / v o l - t i m eb=m i c r o o r g a n i s m sd e c a yc o e f f i c i e n t ,t i m e ’S = m i c r o b i a lm a s sc o n c e n t r a t i o n ,m a s s / v o l .D i v i d i n ge q u a t i o n( 2 4 )b y S a n dr e a r r a n g i n gy i e l d s :( 6 L / 6 t ) / S= a ( 6 S / 6 t ) / S- b( 2 0 )3.515 1.4 1.31.20.70.50.40.30.20.1 8Maxlmizallonr—RecoveyPeriodK=1.37day-i/K0.50day-1Ks=400mgIL/Ks=io,55o mgLAI,j•ppIIIIIII012S4567S910iiObau.4EHMaximizationReccNelyPeriod10—.-.....Note:All ninningconditionsareIllustrated.lnFlguro5.22(c)CII45810a 1.5 0.5RecoveryPerioda=3.52b=-0.93day-ir=0.844..020.40.60.61(61.161)13,day-i1.21.41.632.50.5(c)00=1.67day-i020.40.50.611.21.41.61.8202OlAFExpeiimental RunningconditionsFigure5.22AnEstimationof ExperimentalKineticsDuringmaximizationandrecoveryperiod(a)aandb;(b)KandKs; (C)Kh; (d)ParticulateCODHydrolysis1 0 9B y p l o t t i n g ( c L I 5 t ) / Sa g a i n s t( 6 S / 6 t ) / S , a a n db c a nb eo b t a i n e d a st h e s l o p e a n dt h e i n t e r c e p to ft h e l i n e ,r e s p e c t i v e l y , a ss h o w ni nF i g u r e5 . 2 2( a ) .T h e s u b s t r a t eu t i l i z a t i o nr a t e c a na l s o b e r e l a t e dt os u b s t r a t ea n dm i c r o o r g a n i s m s c o n c e n t r a t i o n s :8 L / 6 t= ( k L e S ) / ( K s + L e )( 2 1 )w h e r ek = m a x i m u mr a t eo fs u b s t r a t e u t i l i z a t i o np e r u n i t w e i g h to fm i c r o o r g a n i s m s ,t i m e ’K s= h a l fv e l o c i t yc o e f f i c i e n t ,m a s s / v o l ,e q u a lt o s u b s t r a t ec o n c e n t r a t i o nw h e n8 L I 5 t= ( 1 / 2 ) kL e= e f f l u e n ts u b s t r a t em a s s c o n c e n t r a t i o n ,m a s s / v o l .L= i n f l u e n ts u b s t r a t e m a s sc o n c e n t r a t i o n ,m a s s / v o l .R e a r r a n g i n ge q u a t i o n( 2 6 ) :( 6 L / 6 t ) / S=( k L e ) / ( K s + L e )B y a p p l y i n gt h ec l a s s i cp l o t ( M o n o dt y p e )b e t w e e n( 6 L / 6 t ) / Sa g a i n s tL e , t h e ka n dK sv a l u e sc a n b eo b t a i n e d ,a ss h o w ni nF i g u r e 5 . 2 2( b ) .I n T a b l e 5 . 4a n dF i g u r e5 . 2 2 ( a ) ,t h ed a t as h o wo n l yam o d e r a t ec o r r e l a t i o nw i t ht h e l i n e( r2 = 0 . 6 6 - 0 . 7 1 )o b t a i n e db yr e g r e s s i o na n a l y s i s ,w i t h“ a ” a n d“ b ”v a l u e sp a r t i c u l a r l ys u s p e c t .H o w e v e r ,d e s p i t et h e s es h o r t c o m i n g s ,o n eo f t h ek i n e t i cc o e f f i c i e n t s ,i np a r t i c u l a r ,d o e s s h o ws o m e e v i d e n c eo f110what may be happening inside the M-UASB during maximization and recovery periods.During maximization, as the loading rate increases step-by-step, the k value is about 1.4day’, compared with 0.50 day’ during the recovery period.Table5.4 Statistical Constants and Kinetics During the Maximization and RecoveryTable 5.4 Statistical Constants and KineticsL During maximization and recovery periodKinetics Coefficients ‘ A-LJASB MUASBand constants....Maximization Recovery period Maximization Recovery periodn 4 5.00 4.00r 0.95 0.80 0.85Kh 1.706x 0.75 1.70a (1.80) 3.50b 2.65 (0.95)K 1.40 0.50Ks 400 10,550%Par.COD Hydrolysi 14-29 3-26Note: n = number of data pointthis tendency seems to reverse itself during the recovery period, as the loading rate isdecreased step-by-step, (as shown in Figure 5.22 (b)). This result is in agreement withthose reported by Chen (1978) where k was practically constant at low influent loadings‘but it increased rapidly at high loading rates. Unfortunately, none of the othercoefficients lend themselves to detinitive conclusions at this time and a more detailed“kinetic study” would be needed to advance any hypotheses further. Such an in-depthanalysis could not be justified in this study.1 1 15 . 2 . 2 . 4O p t i m u m I o a d m gC a p a c i t yS i n c et h i sp r o c e s s i s a t w o - p h a s e U A S B - U A S Bs y s t e m ,o p t i m u ml o a d i n g c a p a c i t ys h o u l db ec o n s i d e r e d s e p a r a t e l ya s A - U A S B a n d M - U A S B .H o w e v e r , i f t h es y s t e mi sc o n s i d e r e d a saw h o l e , t h e o p t i m u ml o a d i n g c a p a c i t yo f t h e M - U A S B i s r e a l l yt h e s y s t e ml o a d i n g c a p a c i t y , b e c a u s et h e m a x i m u ms p a c e l o a d i n g c a p a c i t y o f M - U A S Bi s t h e r a t e -l i m i t i n gs t e po f t h ew h o l es y s t e m .H o w e v e r , t h e o p t i m u ml o a d i n g c a p a c i t y o f t h eMU A S Bi sn o tn e c e s s a r i l yt h e o p t i m u mo n ef o r t h e A - U A S B .I n f a c t ,t h e l a t t e rc a n h a n d l ea h i g h e rl o a d i n gr a t e b e c a u s e t h eg r o w t hr a t eo f a c i d o g e n si sp r e d o m i n a n ta n ds i g n i f i c a n t l yg r e a t e r t h a n m e t h a n o g e n s .T oo p t i m i z et h e s y s t e ml o a d i n g c a p a c i t yw i t hr e s p e c tt op o l l u t i o nc o n t r o l a n dC H4 g a s p r o d u c t i o n ,t h ef o l l o w i n g t w o p a r t i c u l a rc a s e sa r ep r e s e n t e d :( a ) C a s e 1 :O v e r a l l S y s t e mL o a d i n g C a p a c i t yS y s t e ml o a d i n g c a p a c i t yi sd e p e n d e n tl a r g e l yo n s y s t e mc o n f i g u r a t i o na n do p e r a t i o n a lc o n d i t i o n s .D i f f e r e n c e si nt h ec o n f i g u r a t i o na n do p e r a t i n gc o n d i t i o n sc a na f f e c tt h e o p t i m u ms y s t e ml o a d i n g c a p a c i t y .F i g u r e5 . 2 3s h o w s t h eo p t i m u mo p e r a t i n gc o n d i t i o na t 2 a n d 2 . 7d a y s H R T sf o r t h eM - U A S B ,r e s u l t i n gf r o mt w op r e d i c t i v em o d e l so f C O Dr e m o v a l e f f i c i e n c ya n d C H4g a sp r o d u c t i o nd u r i n gt h e s y s t e mm a x i m i z a t i o na n dr e c o v e r yp e r i o d s ,r e s p e c t i v e l y .T h e s em o d e l s a r ef o r m u l a t e db a s e do n t h e C O D( s o l . )r e m o v a le f f i c i e n c ya n d C H4 g a sp r o d u c t i o nr e l a t i v et o t h eH R To f M - U A S Ba s :>0Ea )IU00C u>0EG )00H R T ,d a y s- 3 . 51 ?EC . )E- 2 . 5I02 . 52EDC . )SC . )1 . 5I0I//1 1 2- 4 . 5- 4— 3( a )A%C O D( F . ) r e m o v a lC H 4 , c u . i / c u . m - dAV( 2 )A( 1 ) V = 8 8 . 1 3 + 7 . 2 7 I n X ( r2=0 . 7 4 >( 2 ) V = 5 . 2 9 - 2 . 5 9I n X ( r0 . 9 0 )1 2 01 0 08 06 04 02 001 0 08 06 04 02 0001 2345— 2— 1 . 53% C O D( F H . ) r e m o v a lC H 4 ,C u/ / , / / 9 / Z( )Q— . . . . . - - - . . -D \I/f 4( 3 ) V=1 . 2 7 8 + 1 9 . 9 1 X ( r2=0 . 9 9 )‘‘- 0 . 3 0 4( 4 ) Y = 2 . 4 4 X( r = 0 . 9 3 )/0 123451F i g u r e 5 . 2 3A P r e d i c t e dO p t i m a l O p e r a t i n gH R T( a )M a x i m i z a t i o nP r o c e s s ; ( b )R e c o v e r yP e r i o d1 1 3D u r i n gt h e m a x i m i z a t i o np r o c e s s :Y 2= 8 8 . 1 3 + 7 . 2 7 i n X 2( 2 3 )w h e r eY 2=%s o l u b l eC O Dr e m o v a le f f i c i e n c yX 2 H R T( M - U A S B ) , d a y s0 . 7 4F o r C H4 g a sp r o d u c t i o n , t h e p r e d i c t i v em o d e l i s a s f o l l o w s :Y 3 = 5 . 2 9 - 2 . 5 9I n X 3( 2 4 )w h e r eY 3 = C H4 g a s p r o d u c t i o n ,L i dX 3H R T ( M - U A S B ) ,d a y sr2 = 0 . 9 0D u r i n g t h er e c o v e r yp e r i o d :Y 4 = 2 . 4 4X 4 °3 0 4( 2 5 )w h e r eY 4=%s o l u b l eC O D r e m o v a le f f i c i e n c yX 4= H R T ( M - U A S B ) ,d a y sr2 = 0 . 9 3F o r C H4g a sp r o d u c t i o n ,t h e p r e d i c t i v em o d e li s a s f o l l o w s :Y 5=1 . 2 7 8 + 1 9 . 9 1X 5( 2 6 )1 1 4w h e r e Y 5= C H4g a sp r o d u c t i o n ,L i dX 5= H R T ( M - U A S B ) ,d a y sr2= 0 . 9 9A s s h o w n i n F i g u r e5 . 2 3 , t h e o v e r a l l o p t i m u ms y s t e m o p e r a t i n gc o n d i t i o ni sp r e d i c t e da t a n H R To f 2 . 0 d a y s , w i t h9 0 %C O D ( s o l . ) r e m o v a le f f i c i e n c ya n d 3 . 6m3/m-d o f C H4 g a s p r o d u c t i o n . T h i s o p t i m u m H R T c o r r e s p o n d st ot h e o p t i m u mp o i n to b t a i n e df r o mt h eC O2a n d V F A j a l k a l i n i t yr a t i o d a t aa t H R T sf r o m 1 . 5 - 2 . 2 5d a y s , a ss h o w ni n F i g u r e5 . 1 3 a n d5 . 1 4 . F i g u r e 5 . 1 5i n d i c a t e sa n o p t i m u mf l o wr a t eo f 1 6 . 1 0L i d ,e q u i v a l e n tt oa nH R T o f 1 . 5 5d a y sw i t h9 5%C O D r e m o v a le f f i c i e n c ya n d a p p r o x i m a t e l y7 5 - 8 0% o f t h e t h e o r e t i c a lC H4 g a sp r o d u c t i o n .T h e o p t i m u mR R ’ sa r e t h e nc a l c u l a t e da s1 . 6 a n d2 . 5 . G h o s h( 1 9 8 4 ) s u g g e s t e dt h a t H R T so f 0 . 9- 1 . 5a n d 4 . 0- 5 . 0 d a y s a r eo p t i m u mf o rA - a n dM - U A S B sr e a c t o r s r e s p e c t i v e l y ,a n dC h a n ge ta l .( 1 9 8 9 ) r e p o r t e dt h a ta nH R T o f 2d a y sw a st h e o p t i m u mf o rt h eA - U A S B .A p p r o x i m a t e l y7 7 %o f t h et h e o r e t i c a lC H4 g a s p r o d u c t i o n( 0 . 4 8 m3/ k g V Sa d d e da t s t a n d a r dt e m p e r a t u r ea n dp r e s s u r e )w a s a c h i e v e dt h r o u g ht h eu s e o fat w o - p h a s eU A S B - U A S Bp r o c e s sa tH R T so f 5 . 5a n d5 . 9d a y s r e s p e c t i v e l y( G h o s h ,1 9 8 4 ) . I np r i n c i p l e ,t h e m i n i m u mS R Tf o rm e t h a n o g e n si s i nt h er a n g eo f 2 . 5 - 4 . 0d a y s ( E a s t m a n , 1 9 8 1 ;A n d r e w s ,1 9 6 5 ; T o r p e y ,1 9 5 5 ;B e r g m a n ,1 9 6 6 ;a n dA n d e r s o n ,1 9 7 8 ) .U S . E P A ( 1 9 7 9 ) ,r e c o m m e n d st h a t t h eo p t i m u mS R Ti se q u a lt o t h em i n i m u mS R Tp l u sa s a f e t yf a c t o ro f 2 . 5 .A p p l y i n gt h eE P Ar e c o m m e n d a t i o nt ot h i sp a r t i c u l a rc a s e ,a s s u m i n gt h a tt h em i n i m u mS R T ( z e r or e m o v a le f f i c i e n c y )i s e q u i v a l e n tt o t h em a x i m u mH R T ,t h e o p t i m u mH R Ti st h e ne q u a lt o1 1 5a p p r o x i m a t e l y1 . 6d a y s ,c o r r e s p o n d i n gt o a m a x i m u m f a i l u r e f l o wr a t e o f 4 0 . 2 2L I d ,c o n s i d e r a b l yh i g h e r t h a n f o u n d i n t h i s s t u d y .( A s u m m a r yo f a v e r a g e r e s p o n s e s a n dp e r f o r m a n c e a te a c h p s e u d o s t e a d y - s t a t e ,u n d e rd i f f e r e n t r u n n i n g c o n d i t i o n s ,i ss h o w ni n T a b l eD 1 . 1o f A p p e n d i xD ) .C o n s i d e r i n g t h e o p t i m u mH R To b t a i n e d f r o m t h i s e x p e r i m e n t a lr e s e a r c h ( 1 . 5 - 2 . 2 5d a y s a sm e n t i o n e d e a r l i e r ) ,t h e o p t i m u m H R T s c i t e di ns e v e r a lp u b l i c a t i o n s ,a sw e l la st h eo n e c a l c u l a t e db a s e d o n t h e U S . E P A r e c o m m e n d a t i o n ,i t i sr e a s o n a b l ea n d s a f e t os u g g e s t t h a tt h e o p t i m u mo p e r a t i n gH R T ’ s f o r t h eM - U A S B a n d t h e o v e r a l l s y s t e m ,a r e2 . 0 a n d4 . 0 d a y sr e s p e c t i v e l y .T h i s 2 - d a y H R T i s as l i g h t l yl o w e rt h a n t h e m i n i m u mr a n g eo f 2 . 5 - 4 . 0 d a yS R T r e c o m m e n d e df o r m e t h a n o g e n sm e n t i o n e da b o v e ; h o w e v e r ,i n t h i sc a s e ,i t i s r e a s o n a b l e s i n c et h e d e s i g n e d s y s t e mi s a t w o - p h a s eo n e , p r o v i d i n gt h eo p t i m u m e n v i r o n m e n tt os t i m u l a t et h e g r o w t ho f m e t h a n o g e n s .I t i s a l s o e q u i p p e dw i t ha r e c y c l ef a c i l i t y t o i n c r e a s et h ec o n t a c tb e t w e e nm i c r o o r g a n i s m sa n d s u b s t r a t ea sw e l la s t o i n c r e a s et h e s y s t e m b u f f e r r i n gc a p a c i t y . M o r e o v e r ,i ti s i n t e r e s t i n gt o n o t e t h a t t h i so p t i m u mH R To f 2 d a y s ,p r e d i c t e d f r o mt h ee x p e r i m e n t a lr e s u l t s d u r i n gt h em a x i m i z a t i o np r o c e s s , i s s h o r t e rt h a n t h a t o f2 . 7 d a y sH R To b t a i n e d a t t h er e c o v e r yp e r i o d ,a s s h o w ni n F i g u r e5 . 2 3 . T h i sm a y b e t h e r e s u l to f a s h i f t i nt h e m i c r o b i a ls t r u c t u r e(ac h a n g ei n p r e d o m i n a n tb a c t e r i a l c o m m u n i t i e sa n d t h e i rm i c r o e n v i r o n m e n t ,a n d a d i f f e r e n c ei n b i o c h e m i c a lp a t h w a y s )o f t h e a c e t o g e n i ca n d m e t h a n o g e n i cb a c t e r i a lc o m m u n i t yi n s i d e t h e M - U A S B .1 1 6( b ) C a s e2 :O p t i m u mL o a d i n g C a p a c i t yo fA -a n dM - U A S B sT h e o p t i m u m2 - d a yH R To ft h eM - U A S B , r e c o m m e n d e d e a r l i e ri n c a s e ( a ) ,e q u i v a l e n tt o a f l o w r a t e o f a b o u t1 6L I d ,i sn o t n e c e s s a r i l yt h e o p t i m u mo n ef o r t h e AU A S B ,s i n c e t h e g r o w t hr a t e o f a c i d o g e n si s p r e d o m i n a n ti n t h e A - U A S B .F r o m F i g u r e5 . 2 4a n dT a b l e D 1 . 1o f A p p e n d i xD , i tc a nb e c o n c l u d e dt h a t r u n n i n gc o n d i t i o nn o . 4 , a ta n A - U A S BH R To f1 . 0( 0 . 9 7 )d a y sa n d e q u i v a l e n tt oa f l o wr a t eo f 2 0L I d ,i s t h eo p t i m u ml o a d i n g c a p a c i t y .T h i si s i na g r e e m e n tw i t h t h eo p t i m u mr a n g eo f0 . 9 - 1 . 5 d a yH R Tf o r a c i d o g e n i cr e a c t o r s r e p o r t e db yG h o s h( 1 9 8 4 ) .A tt h i so p t i m u mr u n n i n gc o n d i t i o n d u r i n gt h em a x i m i z a t i o np e r i o d ,t h eA - U A S Bg e n e r a t e dt h eh i g h e s tV F A / a l k a l i n i t yr a t i oo f7 . 5a t d a y 4 0 , w i t he f f l u e n tC O D( s o l . )o f1 1 , 0 5 5m g / La n dt o t a lV F Ap r o d u c t i o no f5 , 3 0 0m g / L a sH A c . T h e M L V S Sc o n c e n t r a t i o no ft h eA - U A S B a l s oi n c r e a s e ds i g n i f i c a n t l yu pt o 4 2 , 1 5 0m g / L , b u tt h e r ew a so n l yas m a l l c h a n g ei n t h ee f f l u e n tT K Na n d T Pc o n c e n t r a t i o n s ,a ss h o w ni nF i g u r eD 1 . 1a n dD 2 . 1o f A p p e n d i xD .I t i s i n t e r e s t i n gt o n o t et h a tt h e t o t a lV F Aa n dt h e V F A l a l k a l i n i t yr a t i oo ft h eA - U A S Bi n c r e a s e ds i g n i f i c a n t l yd u r i n gt h er e c o v e r yp e r i o d ,a ss h o w ni n F i g u r e5 . 2 4 ( b ) .T h i sm a yb e t h er e s u l to f t h ea b i l i t yo f t h eA - U A S Bt ot o l e r a t es h o c k - l o a d s ,a n dt o s t i m u l a t et h er e a c t o r ’ sa c t i v i t y( L e t t i n g a ,1 9 7 9 a ) .T h eo p t i m u mH R Tr a t i o sb e t w e e nA - a n dM - U A S B s ,a n d a l s ob e t w e e nA - U A S Ba n dt h eo v e r a l ls y s t e m ,a r ea b o u t0 . 6 0 a n d0 . 4 0, r e s p e c t i v e l y( D e t a i l si n T a b l eD 1 . 1o f A p p e n d i xD ) .D i n o p o u l o u( 1 9 8 9 )r e p o r t e dt h a tt h e o p t i m u mv o l u m eo ft h e a c i d o g e n i cr e a c t o rw a s i nt h e r a n g eo f1 2 - 2 5%o ft h eo v e r a l la c t i v e1 1 72 0— i2 0 01 8 0 -+ C H 4 ,l / d‘ %C 0 2: ;C O Do1 2 0- T i m e , d a y s1 4 - ’01 3 - i1 0 0 -:T I m e , d a y s6 -H A c H P rl i m e , d a y s/ \- 6P :: I i f t [ 1 J I i t t f l ZT i m e , d a y sF i g u r e5 . 2 4 A nA - U A S BS y s t e mE f f l u e n t Q u a l i t i e s :D u r i n gt h ep r o c e s sm a x i m i z a t i o n( a )C H 4 p r o d u c t i o n , % C 0 2 , E f f . C O D ; ( b )T o t a lV F A , H A c / H P r , V F A ’ A l k a l i n i t y1 1 8v o l u m ei n a s t u d y , u s i n g a t w o - p h a s e a n a e r o b i c d i g e s t i o ns y s t e mw i t hC S T R a c i d o g e n i cr e a c t o r a n da m e t h a n o g e n i c f l u i d i z e d b e d r e a c t o r t o s t a b i l i z e a s y n t h e t i cw a s t e w a t e r .T h ed i f f e r e n c ei n t h e H R T s r a t i o s i n t h i s c a s e m a y r e s u l t f r o m a l o n g e r h y d r o l y s i s r a t e o f t h ep a r t i c u l a t es y n t h e t i c s l u d g e t a k i n g p l a c e i n t h e U A S B - U A S B p r o c e s s , c o m p a r e d w i t h t h es h o r t e rh y d r o l y s i s r a t e f o r t h e s y n t h e t i cw a s t e w a t e r .5 . 2 . 2 . 5 C o n c l u s i o n sF r o m b o t h s y s t e m p e r f o r m a n c e a n d k i n e t i c c o n s i d e r a t i o n s ,i t a p p e a r st h a tt h eU A S B - U A S B s y s t e m c a n r e c o v e r t o i t so r i g i n a l p e r f o r m a n c e b y a p p l y i n g as t e p - d o w nl o a d i n ga p p r o a c h . A l t h o u g h t h e p e r f o r m a n c e , i n t e r m s o f%C O D r e m o v a l e f f i c i e n c y a n d% C H c o n t e n t ,r e c o v e r e dt o t h e o r i g i n a l v a l u e s ,t h e t o t a l C H4 g a s p r o d u c t i o nw a sr e d u c e da n d t h e o p t i m u m o p e r a t i n g p o i n t b e t w e e n C O D r e m o v a l e f f i c i e n c y a n d g a sp r o d u c t i o n w a s m o v e d a l i t t l e f u r t h e r . T h i sm e a n s t h a t t h e r ew a sa t o t a l s h i f t o f t h es p e c i e s r a t i oa m o n g t h e m i x e d c u l t u r e o f a c e t o g e n s a n dm e t h a n o g e n s i n s i d e t h e MU A S B a f t e r t h e r e c o v e r y p r o c e s s .B a s e d o n t h e r e s u l t s o f t h e s e s t u d i e s , t h e f o l l o w i n gc o n c l u s i o n s c a n b e d r a w n :( 1 ) A c o m b i n a t i o n o f h y d r a u l i c a n do r g a n i co v e r l o a d i n go f t h e M - U A S B r e a c t o rw a sa m a j o r c a u s eo fp r o c e s sf a i l u r e ; t h i s c a n r e s u l t i n M L V S S w a s h o u t ,i n c r e a s e i n t o t a lV F Ac o n c e n t r a t i o n ,r e d u c t i o n o f t h e s y s t e m r e m o v a l e f f i c i e n c y ,a n d c e s s a t i o n o f C H4 g a sp r o d u c t i o n .1 1 9( 2 ) A d r o p i np H a n d a n i n c r e a s e i n t o t a l V F A / a l k a l i n i t yr a t i o , a r e d u c t i o no f C H4g a s p r o d u c t i o n ,a n d a n i n c r e a s ei n t h e e f f l u e n t t o t a lV F A , w e r ea l s o i n d i c a t o r s o f t h ep r o c e s s f a i l u r e .( 3 ) T h em a x i m u mh y d r a u l i c l o a d i n g r a t e sw e r e1 . 6 a n d 0 . 9 0m31 m- d , e q u i v a l e n tt oH R T s o f l e s s t h a n 1 . 1 2 5 a n d 0 . 6 2 5d a y s , f o rt h e M - U A S B a n d t h e w h o l e s y s t e m ,r e s p e c t i v e l y . T h eC H4 g a s p r o d u c t i o nw a s r e d u c e d t ol e s s t h a n 5 0%o f t h e t h e o r e t i c a lv a l u e ,w i t he f f l u e n tC O Da n d t o t a lV F Ao f 9 , 5 4 0m g / La n d 3 , 7 5 0 m g f La s H A c ,r e s p e c t i v e l y .( 4 ) T h eM - U A S Br e c o v e r e de x p o n e n t i a l l yw i t ha ni n c r e a s e i n H R T ( l o a d i n gr e d u c t i o n )i n t e r mo f C O Dr e m o v a le f f i c i e n c y ,b u t l o g a r i t h m i c a l l yw i t hr e s p e c t t o C H4g a sp r o d u c t i o n , a s f o l l o w s :Y = 2 5 . 3 7e o .2 9xY l = 9 . 2 5 + 6 4 . 0 1I n X lw h e r eY= %s o l u b l eC O Dr e m o v a l e f f i c i e n c yX= H R T( M - U A S B ) , d a y sY l= C H4 g a sp r o d u c t i o n ,L i dX l= H R T ( M - U A S B ) ,d a y sT h es y s t e m d i d r e c o v e rb a c k t o i t si n i t i a ls t a g eo f o p e r a t i o nb y a p p l y i n g a t w o - s t e pi n c r e a s eo f t h eH R T M . U A S Ba t 1 . 5 a n d5 . 8t i m e s t h ef a i l u r e H R T , w i t ha d i m e n s i o n a lt i m eo f 5 . 6 0a n d 1 0 f o r t h eM - U A S B a n d t h eo v e r a l ls y s t e m ,r e s p e c t i v e l y .1 2 0( 5 ) T h e s h o c k l o a d s a p p e a r e dt o s t i m u l a t e t h eA - U A S B ’ s a c t i v i t y d u r i n gs y s t e mr e c o v e r y ,b u ti t a p p e a r e d t o h a v en o e f f e c t a t a l lo nt h eM - U A S B , w h e nt h es y s t e mf a i l e dc o m p l e t e l y . T h e r e c o v e r ya p p r o a c h ,e m p l o y i n gt h e s t e p - l o a d i n gr e d u c t i o n a n d t h ei n t e r n a lR R , s e e m e d t o h a v en o s i g n i f i c a n tb e n e f i c i a l e f f e c t , c o m p a r e d w i t ht h e r ea c c l i m a t i z a t i o ni n t e r mo f t i m e r e q u i r e m e n t( b o t h n e e d e d 4 - 5 w e e k st o c o m p l e t e t h ep r o c e s s e s ) . H o w e v e r ,i t d i d p r o v i d es o m e a d v a n t a g e si nt e r m s o f e a s e o fo p e r a t i o n a n da m o r ep r a c t i c a l a p p r o a c hf o ra p o t e n t i a l f u l l - s c a l eo p e r a t i o n .( 6 ) T h eh y d r o l y s i s r a t e g o v e r n i n gt h eA - U A S Bw a sa b o u t1 . 7 0d a y s . T h e s p e c i f i cv e l o c i t yk d u r i n gt h e m a x i m i z a t i o na n d r e c o v e r yp e r i o d s , w a s 1 . 4 0 a n d0 . 5 0 d a y1,r e s p e c t i v e l y .T h e c o r r e s p o n d i n gs u b s t r a t e s a t u r a t i o nc o e f f i c i e n t( h a l fv e l o c i t yc o n s t a n t ,K s ) w a sf o u n d t o b e4 0 0 a n d 1 0 , 5 5 0m g / L d u r i n gt h e m a x i m i z a t i o na n d r e c o v e r y p e r i o d ,r e s p e c t i v e l y .( 7 )T h eo p t i m u mH R Tf o r t h e A - U A S B w a s1 . 0 ( 0 . 9 7 ) d a y s ,w h e r e a s ,t h o s e f o rt h eM - U A S B ,w i t hr e s p e c tt o C O Dr e m o v a le f f i c i e n c ya n d C H4 g a sp r o d u c t i o n ,d u r i n gt h em a x i m i z a t i o n a n dr e c o v e r yp e r i o d , w e r e2 . 0 a n d 2 . 7 d a y s , r e s p e c t i v e l y .T h i ss e e m st o i m p l yt h e r e w a sar e s t r u c t u r i n go f t h eb a c t e r i a lc o m m u n i t yi n s i d et h e M - U A S B ,d u r i n gt h e r e c o v e r yp e r i o d .F o rd e s i g n p u r p o s e s ,t h e o p t i m u m o p e r a t i n gH R T ’ so f 1 a n d 2 d a y s ,a s w e l la st h e R Ro f 1 . 6 a n d2 . 5 t i m e s t h e i n f l u e n tf l o wr a t e ,a r e r e c o m m e n d e df o r Aa n d M - U A S B s ,r e s p e c t i v e l y ,w i t ha c o n s e r v a t i v eo r g a n i c l o a d i n gr a t eo f 1 9k gC O D ( t o t a l ) / m3-d( e q u i v a l e n tt o 0 . 5 5m3/ m- d ) .1 2 1( 8 ) T h eo p t i m u mH R T A UH R T M U Br a t i ow a sa b o u t 0 . 6 0a n d t h eH R T A .u p s i / H R T s y s t e mw a s 0 . 4 0 ,a s a p p l i e d t o t h e t w o - p h a s ea n a e r o b i cd i g e s t i o n o f s e w a g e s l u d g e( U A S B - U A S B ) .1 2 25 . 2 . 3 D e v e l o p m e n t o f S y s t e mD e s i g n C r i t e r i aT h e m a i n r e s e a r c hg o a lw a st oe v a l u a t et h e f e a s i b i l i t y o f t h e t w o - p h a s ea n a e r o b i cd i g e s t i o n( U A S B - U A S B ) c o n c e p t , t o s t a b i l i z e a p a r t i c u l a t es u b s t r a t e . T h ef o l l o w i n gs e c t i o n s ,d e a lw i t ht h e s y s t e me f f e c t i v e n e s s( o r p e r f o r m a n c e ) ,s y s t e m s u i t a b i l i t y ( o rl o a d i n g c a p a c i t y ) ,a n d s y s t e m f e a s i b i l i t y , f o l l o w e db y a m o d i f i c a t i o n o f d e s i g n c r i t e r i a a n do p e r a t i o np r o c e d u r e s . F i n a l l y , m a j o r s y s t e m c o n t r o lp a r a m e t e r s a r ee v a l u a t e da n dd i s c u s s e d .5 . 2 . 3 . 1 O p t i m u m S y s t e mP e r f o r m a n c ea n d F e a s i b i l i t yT h e o p t i m u m s y s t e m H R T o f 2 . 8 0 ( 1 . 2 4 + 1 . 5 5 ) d a y s e q u a t e st o a h y d r a u l i c l o a d i n gr a t eo f 0 . 4 0m3/ m- d .T h e o v e r a l l s o l u b l ea n d t o t a l C O D r e m o v a l e f f i c i e n c i e s w e r e9 0 . 7 6a n d 9 8% ,r e s p e c t i v e l y , w i t h6 9%C H4 c o n t e n t a n d 1 7 9L I do f C H4 g a s p r o d u c t i o n( / e q u i v a l e n tt o 7 3% o ft h et h e o r e t i c a lv a l u e ) .A v e r a g ep s e u d o s t e a d y - s t a t e s y s t e mp e r f o r m a n c ea n d e f f l u e n t q u a l i t y , a t t h e o p t i m u mr u n n i n g c o n d i t i o n , a r e s u m m a r i z e di nT a b l e 5 . 5 . I t i s i n t e r e s t i n gt o p o i n t o u t t h a t t h e r e w a s a c t u a l l ys o m e P 04- P ( a n d / o rT P )r e m o v a l ,b u t r a r e l y N H4- N ( a n d / o rT K N )r e m o v a la s s h o w n i n F i g u r e5 . 1 4 . T h i s m a y b ed u e t oc h e m i c a l r e a c t i o n s f o r m i n gp r e c i p i t a t i n g s a l t so f C aa n d / o rM g p h o s p h a t e .H o w e v e r ,t h e r e w a s as m a l l c h a n g e i n N H4- N ( a n d / o rT K N ) . c o n c e n t r a t i o n , s i n c eN H4- Nc a nb e u s e da s a r e l e a s e - a n d - a p p r e h e n di o n t o m a i n t a i n t h eb a l a n c e o f b u f f e r c a p a c i t y1 2 3T a b l e5 5S u m m a r yo f A v e r a g e R e s p o n s e sa tt h eO p t i m a lS y s t e mO p e r a t i n g. s e d oSA v e r a g e R e s p o n s e s E x p e r i m e n t a l R u n n i n g C o n d i t i o nP r o c e s s e s2 — p h a s e( U A S B — U A S B )R u n n i n gP e r i o d , d a y s 3 6S l u d g e F e e d R a t i o( S R )8 0 / 2 0R e c y c l e R a t i o ( R R ) 2 / 3I n f l u e n t F l o w , l / d 1 6 . 1 0H R T ,d a y sA - U A S B 1 . 2 5M - U A S B1 . 5 5S y s t e m 2 . 8 0L o a d i n gR a t ec u . m / c u . m — d 0 . 3 5K g C O D ( s o l . ) / c u . m — d 2 . 1 5E f f l u e n tQ u a l i t yS o l i d s ,m g I LT S2 8 5 0V S1 2 3 0T S S1 8 5T V S S1 1 0C O D , m g I LT o t a l C O D 6 8 0C O D ( s o l . ) 5 5 0I n o r g a n i c s ,m g / LN H 4 - N 3 0 0T K N 4 0 0T P 8 5P 0 4 - P 1 5V F A , m g / LH A c4 0H P r 6 5l s o — H B r0H B r 5A - H V r0l s o — H V r 0H V r0H H e0T o t a l V F Am g / La sH A c9 51 2 4T a b l e5 5S u m m a r yo fA v e r a g eR e s p o n s e s a tt h eO p t i m a lS y s t e m O p e r a t i n gL J n d e r . 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S e U d oS I e á d y S t à t e Q nA v e r a g e R e s p o n s e sE x p e r i m e n t a l R u n n i n g C o n d i t i o nP r o c e s s e s2 — p h a s e( U A S B — U A S B )A l k a l i n i t y ,m g / La s C a C O 3A - U A S B9 6 0M - U A S B2 5 2 0T o t a lV F A / A l kA - U A S B4 . 9 0M - U A S B0 . 0 5S y s t e m R e m o v a l E f f i c i e n c yS o l i d s , %T S S9 9 . 0 0C O D , %C O D ( s o l . )9 1 . 0 0T o t a l C O D9 8 . 0 0I n o r g a n i c s ,%P 0 4 — P8 8 . 0 0T P3 9 . 0 0M e t h a n eG a sF l o w ,l / dT o t a lG a s3 1 0 . 0 0C H 4G a s1 8 0 . 0 0C H 4 P r o d u c t i v i t yl I d1 8 0 . 0 0c u . m l c u . m — d4 . 0 0c u . m l c u . m — d @ S C3 . 5 0c u . m / k g C O D ( T o t a l ) a d d e d@ S C0 . 2 5% o ft h e o r e t i c a l C H 4 P r o d u c t i o n7 3 . 0 0% C H 4c o n t e n t6 9 . 0 01 2 5o f t h eM - U A S B ,a sw e l la s a b a s i cg r o w t h n u t r i e n t .I t i s d i f f i c u l t t o c o m p a r et h e p e r f o r m a n c eo fd i f f e r e n t p r o c e s s e s , s i n c ee a c hp r o c e s s h a si t so w nu n i q u ec h a r a c t e r i s t i c s , c o n f i g u r a t i o n ,a n d o p e r a t i n gc o n d i t i o n s .H o w e v e r ,t h eo p t i m u ms y s t e mp e r f o r m a n c e a n d e f f l u e n t q u a l i t yc a n b e u s e da sg u i d e l i n e st oe v a l u a t eb o t he f f e c t i v e n e s s a n d s u i t a b i l i t y ,p o s s i b l y l e a d i n g t o a ne v a l u a t i o no f s y s t e mf e a s i b i l i t y . A s s h o w ni n T a b l e 5 . 5 ,i t i s c l e a r t h a t t h e t w o - p h a s eU A S B - U A S Bc o n c e p t ,a t a ne x t r e m e l yl o wo p e r a t i n gH R T ( 2 . 8 d a y s ) ,p e r f o r m s r e a s o n a b l y w e l l w i t hC H4 g a sp r o d u c t i o n o f a b o u t7 3%t h e o r e t i c a lC H4 v a l u e ,e f f l u e n t C O D o f5 5 0 m g / L ,a n dv o l a t i l ea c i d so f 9 5m g / L .T h ei n t e r n a lR R a p p e a r st op l a y am a j o rr o l e i nc o n t r o l l i n ga n dm a i n t a i n i n g t h es y s t e mp e r f o r m a n c e b y i n c r e a s i n gt h ec o n t a c t b e t w e e nm i c r o o r g a n i s m sa n ds u b s t r a t e s ,r e d u c i n gt h ee f f e c to f s h o c kl o a d i n g ,a n d i n c r e a s i n gt h es y s t e mb u f f e r i n gc a p a c i t y .C o m b i n i n gi n f l u e n tl o a d i n gr a t e c o n t r o la n da p p r o p r i a t eR R s , i ti s t h u s p o s s i b l e t om a i n t a i nag o o ds y s t e mp e r f o r m a n c eo rt o a s s i s ti n r e c o v e r i n gt h e s y s t e m , i n c a s eo f a ni n t e r r u p t i o na n d / o rf a i l u r e .5 . 2 . 3 . 2M o d i f i c a t i o no f D e s i g nC r i t e r i aa n dO p e r a t i o nD e v e l o p m e n to fa n a e r o b i cd i g e s t i o ns y s t e md e s i g nh a s r e c e n t l ym o v e dt o w a r d s“ h i g hr a t e ”d i g e s t i o ns y s t e m s .E a c h s y s t e mh a s i t so w n m e r i t s ,l i m i t a t i o n s ,a n d p o t e n t i a l ,a n dd e p e n d sl a r g e l yo n t h e l o c a ls i t u a t i o n ,c h a r a c t e r i s t i c so ft h e w a s t e st ob e t r e a t e d ,a n d1 2 6t h e p e r f o r m a n c ea n d s p e c i f i ce x p e r i e n c eo fe a c hs y s t e md e s i g n e r i n e a c h t y p e o f s y s t e mc o n f i g u r a t i o n .A l t h o u g ht h et w o - p h a s ea n a e r o b i cd i g e s t i o n c o n c e p t w o r k se x c e p t i o n a l l yw e l l ,c o m p a r e dw i t h a s i n g l e s t a g eo n e , t h e r e i s s t i l ln ou n i v e r s a l ,t w o - p h a s ed i g e s t i o nc o n f i g u r a t i o nt h a ti s o p t i m u mf o r a l ls i t u a t i o n s .T h e c h o i c eo ft h ef e r m e n t e rt y p ed e p e n d sl a r g e l y o nt h e p h y s i c a l , c h e m i c a l a n d b i o l o g i c a lc h a r a c t e r i s t i c so f t h e f e e d a n dt h eo b j e c t i v eo ft r e a t m e n t , i e . , w h e t h e ri ti sp o l l u t i o nc o n t r o l o rm a x i m i z a t i o no f C H4 g a sp r o d u c t i o n .T h ed e s i g no f t h e t w o - p h a s eU A S B - U A S Bp r o c e s s m u s t e n s u r e a u n i f o r md i s t r i b u t i o n o f i n f l u e n tf e e d a tt h e l o w e rp a r t o f t h er e a c t o r ,as u f f i c i e n tc r o s s - s e c t i o nt op r e v e n tb i o m a s s e n t r a i n m e n t ,a n da ne f f e c t i v es e p a r a t i o n o f g a s ,b i o m a s s ,a n d l i q u i d .T h ek e y s t ot h e s u c c e s s f u la n a e r o b i c s t a b i l i z a t i o np r o c e s s e sa r e t oi n c r e a s et h ec o n t a c tb e t w e e nm i c r o o r g a n i s m sa n ds u b s t r a t e sa sw e l la s t oi n c r e a s et h e s y s t e mb u f fe r r i n gc a p a c i t y . S l u d g e r e c y c l i n ga l s op l a y s am a j o r r o l ei nt h e s e a s p e c t s ,w h i c hs u b s e q u e n t l yi m p r o v e st h ep r o c e s sp e r f o r m a n c ea n ds t a b i l i t y .B a s e do n t h e r e s u l t so ft h i ss t u d y ,o p t i m u md e s i g nH R T ’ s f o r A - a n d M - U A S B ’ sr e a c t o r s a r ea b o u t 1a n d 2 d a y s , w i t hR R s2 a n d3 t i m e st h ei n f l u e n tf l o wr a t e ,r e s p e c t i v e l y .M o s to f t h er e a c t i o n ss e e mt oo c c u ra t t h el o w e r p a r to f t h er e a c t o r s ( s l u d g eb e da n db l a n k e tp o r t i o n ) .A ss h o w ni nF i g u r e5 . 2 5 ,t h e r ei s n od i f f e r e n c ei n t h ee f f l u e n tV F Ac o n c e n t r a t i o np r o f i l e f r o mt h eb o t t o mt o t h eu p p e rp a r to f t h eM - U A S Br e a c t o r .P o s s i b l er e a s o n sf o r t h i sp h e n o m e n o nm a yb e d u et o h i g h c o n c e n t r a t i o n so fa c t i v ea n a e r o b i cs l u d g ei nt h e l o w e rp a r to f t h er e a c t o r ,t h ee f f e c t i v em i x i n gc r e a t e d b yt h ei n c o m i n gf l o wr a t e , t h eu p w a r de s c a p e o ft h ep r o d u c e dg a s , a n dt h er e c y c l eo f t h e e f f l u e n tf r o mt h e s l u d g eb l a n k e t .A l l t h e s ef a c t o r s1 2 7F i g u r e5 . 2 5C o m p a r i s o no f T o t a lV F AA l o n g t h eH e i g h t o fM - U A S B :D u r i n gt h eA c c l i m a t i z a t i o nP r o c e s sS l u d g e b l a n k e t V F A1 . 6M A cH P r21 . 2- 0 . 8I -- 0 . 40I i I i0III0 2 0 4 06 08 0l i m e ,d a y s1 2 8c o n t r i b u t e t o i n c r e a s et h e r e m o v a le f f i c i e n c ya t t h e l o w e r p a r t o f t h er e a c t o r .C h r i s t e n s e n( 1 9 8 4 ) f o u n d t h a tC O Dr e m o v a lo c c u r r e dt h r o u g h o u tt h e s l u d g e b e da n db l a n k e t o fa n U A S B r e a c t o r .A ss h o w ni n F i g u r e 5 . 2 5 a n d5 . 2 6 , t h e r e w a s s m a l lc h a n g ei n e f f l u e n tC O D ( s o l . )p r o f i l e s o f b o t h A - a n dM - U A S B s , a f t e r t h e s l u d g eb l a n k e tp o r t i o n ( s a m p l i n gp o i n t n o . 3 a n d 6a ss h o w ni n F i g u r e4 . 2 )d u r i n gt h e a c c l i m a t i z a t i o na n dm a x i m i z a t i o n / r e c o v e r yp e r i o d .T h e s er e s u l t sl e a d t o t h e c o n c l u s i o nt h a t t h e r e a c t o rh e i g h tc o u l d h a v eb e e n r e d u c e dt o5 0 c m sw i t h o u ta n y e f f e c t so nt h e p r o c e s sp e r f o r m a n c e .T h e r a t i o o f r e a c t o r d i a m e t e rt o h e i g h t c o u l dt h e nb ea sl o wa s 1 : 4( 1 2 . 5 / 5 0 ) . H o w e v e r ,f o r d e s i g np u r p o s e s , t h i sr a t i o s h o u l db e c l o s e r t o 1 : 8t o1 : 1 0(d e p e n d i n go n s a f e t yf a c t o r c h o s e n ) ,t o e n s u r e t h a t e x t r as p a c ei s p r o v i d e d f o r t e m p o r a r yg a sa c c u m u l a t i o na n d f o r s c u m f o r m a t i o n .I t i s a l s o i m p o r t a n tt h a t p e a kh y d r a u l i cl o a d i n g b e t a k e ni n t o a c c o u n t f o rt h ed e s i g no f d i g e s t e r v o l u m e .T h e d e s i g ns y s t e m h y d r a u l i cl o a d i n g r a t ei s c o n s e r v a t i v e l ys e ti n t h er a n g e o f 0 . 5 5m31 m- d e q u i v a l e n t t o 1 9 k g C O D ( t o t a l ) / m3-d,a t 3 50C w i t ha nS R 8 O / 2 0a n d R R 1 . 6 / 2 . 5 .S i n c e m o s tm u n i c i p a l w a s t e w a t e rt r e a t m e n tp r o c e s s e s p r o d u c ea s l u d g er a t i o ( S R )o f a b o u t6 0 / 4 0( b yw e i g h t ) ,t h eo p t i m u mr a t i o o f t h i ss t u d y ( 8 0 / 2 0 )c a nb e m o d i f i e d t o c o m p e n s a t ef o rt h e e x c e s s a m o u n to f w a s t ea c t i v a t e ds l u d g e ( W A S )p r o d u c e d .T h i s c a n b e d o n eb ye i t h e ri n c r e a s i n g t h e r a t i oo f W A S p o r t i o no r u s i n gt h ee x c e s s a m o u n t ,w h i c hi s f u l lo fn u t r i e n t s( N a n d P ) , f o r s o i lc o n d i t i o n i n ga n d / o rc o m p o s t i n g .A s u m m a r yo f r e c o m m e n d e dd e s i g nc r i t e r i a/s t a r t - u p a n da c c l i m a t i z a t i o n/a n d o p e r a t i o nf o r t h et w o - p h a s ea n a e r o b i c d i g e s t i o no f s e w a g es l u d g e( U A S B - U A S B )p r o c e s si s i l l u s t r a t e di n T a b l e5 . 6 .fS a m p l i n gP o i n t n o .LS p . 1 S p . 3 S p . 4S p . 51 2 9S a m p h n gP o i n t n o .S p . 8S p . 7S p . 6S p . 5F i g u r e5 . 2 6 C O D( s o l u b l e )P r o f i l e so fa T w o - p h a s eU A S B - U A S BP r o c e s s :D u r i n gM a x i m i z a t i o na n dR e c o v e r yP e r i o d( a )A - U A S B ;( b )M - U A S B ;( c )R u n n i n g C o n d i t i o n sN o t e :A l l s a m p l i n gl o c a t i o n sa r ei l l u s t r a t e di n F i g . 4 . 2C O O ( s o l u b l e ) . m g / L( T h o l i s a n c ; )I III I I.6 i i1 62 22 73 33 7 4 24 75 15 88 16 57 07 58 4 9 8 1 0 2 1 0 7T i m e ,d a y s( a )C O D ( s o l u b l e ) ,m g / L ( T h o u s a n d s )I6 1 1 1 6 2 2 2 7 3 33 74 2 4 75 15 86 1 6 6T i m e ,d a y s7 0 7 58 4 9 6 1 0 2 1 0 7( b )[ x p e a i r u n n i n gc o n d i t i o n sE x p e r i m e n t a lP e r l o d s itM a x i m i z a t i o nS y s t e mH R T ,d a y s5 . 6 5 -6 . 8 44 . 6 5 -5 . 1 62 . 7 6 -3 . 1 62 . 1 3 - 2 . 2 01 . 5 5 - 1 . 8 22 . 3 0- 2 . 7 72 . 7 1- 3 . 2 13 6 3- 3 . 9 57 3 2- 9 . 0 0D a y s1 - 1 5( c )VAR e c o v e r ’ , ’P e r i o dV2 0 - 2 93 3- 3 74 0- 4 44 7 - 5 15 4 - 5 86 1- 6 56 8- 7 27 5 - 1 0 71 3 0T a b l e 5 . . 6 R e c O m m e n d e dd e s i g nca n d o p e r a t i o no fa t w o — p h a s ea n a e r o b i cd i g e s t i o no f s e w a g es l u d g e( U A S B - U A S B )p r o c e s sD e s i g nc r i t e r i aV a l u e sO p t i m u m H R T ,d a y sA - U A S B1 . 0 0M - U A S B2 . 0 0R R , Q r I Q i n( L o w e r 1 / 3 o f t h er e a c t o r h e i g h t )A - U A S B2 . 0 0M - U A S B3 . 0 0R e a c t o r d i a m e t e r / h e i g h tr a t i o 1 : 1 0G a s c o l l e c t i o na p e r t u r e ,m 3 / m 2 — d0 . 7 0( M i do ft h e r e a c t o rh e i g h tw i t h5 0d e g r e ei n c l i n e dw a l l )O r g a n i c L o a d i n gR a t e , k g C O D ( t o t a l ) / m 3 — d1 9 . 0 0S t a r t - u pa n da c c l i m a t i z a t i o nS y s t e ms e e d i n gr a t i o 1 : 1S t a r t — u pl o a d i n gr a t e ,k g C O D / k g V S S — d0 . 1 0S t e p — u pl o a d i n gr a t ei f :C O D ( s o L )r e m o v a le f f i c i e n c y ,%> 8 0H R T ,d a y s 2 — 3p H c o n t r o l ,0 . 1N , N a O HA - U A S B5 . 0 - 5 . 3M - U A S B7 . 0 - 7 . 3T e m p e r a t u r e ,oC 3 5 . 0 0S R8 0 / 2 0( a )R R4 / 7( a )S y s t e mO p e r a t i o nH y d r a u l i cl o a d i n gr a t e ,m 3 / m 3 — d0 . 3 5p H v a l u e sA - U A S B5 . 0 - 5 . 3M - U A S B7 . 0 - 7 . 3T e m p e r a t u r e ,oC 3 5 . 0 0S R8 0 / 2 0( a )R R2 / 3( a )R e c o v e r yP r o c e s s2 — s t e pi n c r e a s i n gH R T1. 5 Q 1 5 . 8 Q( a )( w h e r eQ= F a i l u r eH R T )N o t e :( a )= n l I n 2 , w h e r en i=A — U A S Ba n d n 2= M — U A S B1 3 1T oo p e r a t e t h e s y s t e ms u c c e s s f u l l y a n d e f f e c t i v e l y ,p r o p e r s t a r t - u pa n da c c l i m a t i z a t i o na r ev e r y i m p o r t a n t s t e p s ;a l s o ,c l o s em o n i t o r i n go fs e v e r a lm a j o rc o n t r o lp a r a m e t e r si sa b s o l u t e l yn e c e s s a r yt o m a i n t a i na na c c e p t a b l ep e r f o r m a n c e .p Hi so n e o f t h e m o s ts e n s i t i v ea n d p r a c t i c a lc o n t r o l p a r a m e t e r su s e d t om o n i t o rt h ea n a e r o b i cs t a b i l i z a t i o np r o c e s s( a s s h o w ni nF i g u r e 5 . 2 7 ) .As i g n i f i c a n td r o pa n d r i s e i np Hd u r i n g t h ep r o c e s sf a i l u r e a n dr e c o v e r y p e r i o d d e m o n s t r a t e st h e e f f e c t i v e n e s so f t h i s c o n t r o l p a r a m e t e r . I ti sa l s oi n t e r e s t i n gt op o i n to u t t h a tt h e p Hv a l u e so f A - a n dM - U A S B sa r e p r a c t i c a l l yc o n s t a n ta t5 . 0 - 5 . 3 a n d 7 . 0 - 7 . 3 r e s p e c t i v e l y ,i n d i c a t i n gt h a t b o t hr e a c t o r sa r e n a t u r a l l yb u f f e r e d b yt h e m s e l v e s . T h i sm a y r e s u l tf r o ma b a l a n c eb e t w e e nt h eNH4- i o n s , c a t i o n sr e l e a s e df r o m t h ef a t t ya c i d s a l t s ,a n d HCO3-ions f o r m e d b y C 02, c o n t r i b u t e dp a r t l y b yt h er e c y c l i n gp r o c e s si n b o t h r e a c t o r s a n dh e l p i n gt o i n c r e a s ea n ds t a b i l i z et h e b u f f e rc a p a c i t y( T r u d e l l ,1 9 8 5 ) .R e m e d i a la c t i o n ss h o u l db e q u i c k l y m a d e i ft h e r ea r es i g n i f i c a n tc h a n g e si n s y s t e mc o n t r o lp a r a m e t e r st h a ta r e p r o v i d i n ga no v e r a l lp i c t u r e o f w h a th a p p e n s i n s i d et h er e a c t o ru n d e rd i f f e r e n tc i r c u m s t a n c e s .H y d r a u l i cl o a d i n gr e d u c t i o na n dr e c y c l i n gf a c i l i t ya r e e f f e c t i v em e a s u r e si n r e c o v e r i n gt h es y s t e m ,b yi n c r e a s i n gt h e s y s t e mb u f f e r i n gc a p a c i t y a n dp r o v i d i n gt h e m e t h a n o g e n sab e t t e ro p p o r t u n i t yt o c o n t a c tw i t hs u b s t r a t e sa n d s u r v i v eu n d e rt h i s s t r e s sc o n d i t i o n s .p Ha d j u s t m e n tw i t ha na l k a l i n ea d d i t i o ni sa n o t h e rp r o m i s i n gm e a s u r et oa l l e v i a t et h e p r o b l e m .T h e r e f o r e ,ac o m b i n a t i o no f t h e s em e a s u r e sm a yb en e c e s s a r yi f t h es y s t e m i ss e v e r e l yd a m a g e d .A l l o ft h e s em e a s u r e sa r ed e s i g n e dt oa v o i das y s t e mw a s h o u t ,i fa ta l lp o s s i b l e .6 . 86 . 66 . 4zE6 . 2065 . 85 . 65 . 45 . 254 . 8Figure 5.27 rH Variation in A-UASB and M-UASB:( a )S e q u e n c ea n d3E x p e r i m e n t s ;( b ) M a x i m i z a t i o na n dR e c o v e r yP e r i o d7 . 47 . 27‘1H i l l 1 1 1 1l U1 3 2r f— I( a )P h a s e2 E x p e r i m e n tP h a s e3 E x p e r i m e n tf- - - — - --— -I A - U A S B+ M 4 J A S B—--4- ,.T. ill “‘ii•o -T——-r —, %r ‘-JII2 14 16 18 11 0 11 2 11 4 11 6 11 8 1 2 0 12 2 12 4 12 6 12 8 1T i m e ,d a y s- _ _ . -—IC )( b )7 . 276 . 86 . 66 . 46 . 265 . 85 . 65 . 45 . 254 . 84 . 64M a x I m i z a t i o n--J ” _ - LI A - U A S B+ M - I J A S B-__—H C f W A F V- . . ,r o I I u Jp2 9 53 1 53 3 5 3 5 53 7 53 9 5T I m e ,d a y s1 3 3C H A P T E RS I XC O N C L U S I O N SA N D R E C O M M E N D A T I O N S6 . 1 C O N C L U S I O N SM o d i f i c a t i o n a n d i m p r o v e m e n to f a p r o c e s sc o n f i g u r a t i o n , s t a r t - u pa n da c c l i m a t i z a t i o n , a n ds y s t e m o p e r a t i o n o fa t w o - p h a s e U A S B - U A S Bp r o c e s sh a v eb e e ns t u d i e d .T h es y s t e m a p p e a r s t o b ef e a s i b l e , e f f e c t i v e ,a n d s u i t a b l ef o r s t a b i l i z i n gs e w a g es l u d g e , w i t h p r o m i s i n gr e s u l t s . B a s e d o n t h e r e s u l t so f t h i sr e s e a r c h p r o g r a m , t h ef o l l o w i n gm a j o r c o n c l u s i o n sc a n b e m a d e :( 1 ) . At w o - p h a s eU A S B - U A S Bp r o c e s sa p p e a r s t ob e f e a s i b l e a n de f f e c t i v ef o rs t a b i l i z i n gs e w a g e s l u d g e ,w i t ha h i g ho r g a n i c l o a d i n gr a t e , w h i l em a i n t a i n i n g a na c c e p t a b l el e v e l o f s u p e r n a t a n tq u a l i t y a n dC H4 g a s p r o d u c t i o n .T h e s y s t e ma l s o h a s ah i g h p o t e n t i a lt o r e c o v e re f f e c t i v e l ya f t e ras e r i o u sf a i l u r e ,u s i n g a s t e p - l o a d i n gr e d u c t i o na n d i n t e r n a lr e c i r c u l a t i o n ( R R )a p p r o a c h .T h e“ T w o - p h a s e ”c o n c e p th a s t h u s p r o v e nt ob e s u c c e s s f u li n t r e a t i n gs e w a g es l u d g e .H y d r o l y s i s a n d a c i d i f i c a t i o np r e d o m i n a t ei n t h eA - U A S B ,w h i l ea c e t o g e n e s i sa n d m e t h a n o g e n e s i sd o m i n a t ei n t h eM - U A S B . M o s t o f t h er e a c t i o n so c c u r a t t h e l o w e rp a r t o fb o t h r e a c t o r s(S l u d g e b l a n k e t a n db e d ) .( 2 ) . T h em o s te f f e c t i v ea n dp r a c t i c a la p p r o a c h t o a c c e l e r a t et h e a c c l i m a t i z a t i o np r o c e s si s t op r o v i d ea c o n t i n u o u s ,s t e p - u po r g a n i c l o a d i n gr a t e ,t o m a t c ht h e b a c t e r i a l g r o w t h .1 3 4T h e s t a r t - u pl o a d i n gr a t er e c o m m e n d e di s 1 . 2 g C O D / L - d , w i t ha s e e ds l u d g et a k e nf r o ma na n a e r o b i cd i g e s t e rf o r t h eM - U A S B ,a n da na c c l i m a t i z e d s e e d s l u d g e f o rt h e AU A S B ,a t t h e r a t i o o f 1 : 1( b yv o l u m e ) .T h ew a s h o u tp r o c e s s o c c u r r e da f t e rt w o w e e k so f a c c l i m a t i z a t i o na tas l u d g el o a d i n go f0 . 4 0k g C O D / k g V S S - d .T h e a c c l i m a t i z a t i o np r o c e s sr e a c h e d ap s e u d o s t e a d y - s t a t ew i t h i n 4 - 5w e e k s , w i t h9 1 a n d1 0 0%C O D ( s o l . )a n d V F A r e m o v a le f f i c i e n c i e s , r e s p e c t i v e l y .( 3 ) .U n d e rs p e c i f i cc o n t r o lo ft e m p e r a t u r e a t 3 5°C , a n i n f l u e n tf l o wr a t eo f 5 - 6L I d ,a n da p H a t5 . 0 - 5 . 3a n d7 . 0 - 7 . 3f o rt h eA - U A S Ba n dM - U A S Br e s p e c t i v e l y ,t h e o p t i m u m“ B e s tK n o w n ”r u n n i n gc o n d i t i o ni s a t s l u d g er a t i o( S R )8 0 / 2 0a n dr e c y c l er a t i o( R R ) 5 / 8 ;t h i s a c h i e v e dm o r et h a n9 5a n d 9 0%C O D( s o l . )a n d P04-P r e m o v a l e f f i c i e n c i e s , w i t he f f l u e n tC O D( s o l . ) o f3 0 0 m g / L . I n a d d i t i o n ,t h i s “ B e s tK n o w n ”c o n d i t i o np r o d u c e d ah i g hv o l u m eo f C H4 g a s , a b o u t1 . 5 5m3/m-d, e q u i v a l e n t t o a s p e c i f i c C H4 p r o d u c t i o n o f0 . 3 2m3/ k gC O D ( T o t a l ) a d d e d ,a t 7 2% C H4 c o n t e n t . I n t e r n a l r e c i r c u l a t i o n( R R ) s e e m st ob e a n i m p o r t a n t f e a t u r eo ft h e t w o - p h a s es y s t e m ;n o to n l y d o e si ti n c r e a s et h ec o n t a c tb e t w e e nm i c r o o r g a n i s m sa n ds u b s t r a t e s ,b u t a l s oh e l p s t or e c o v e rt h e s y s t e mf r o mas e r i o u s f a i l u r ea n d s t a b i l i z e s ,n a t u r a l l y ,t h eb u f f e r i n gc a p a c i t yi n b o t hA - a n dM - U A S B s .( 4 ) .A c o m b i n a t i o no f h y d r a u l i ca n d o r g a n i co v e r l o a d i n go ft h e M - U A S Bw a sa m a j o rc a u s ef o r p r o c e s sf a i l u r e ,a s i n d i c a t e db yM L V S Sw a s h o u t ,a n i n c r e a s ei n t h e t o t a lV F Ac o n c e n t r a t i o n ,a r e d u c t i o ni n s y s t e mr e m o v a le f f i c i e n c y ,a c e s s a t i o ni nC H4g a sp r o d u c t i o n ,a d r o pi np H , a n da n i n c r e a s ei n t o t a l V F A / a l k a l i n i t yr a t i o .1 3 5( 5 ) . M a x i m u mh y d r a u l i c l o a d i n g r a t e s f o u n d w e r e1 . 6 a n d 0 . 9 0m31 md ,e q u i v a l e n t t oH R T so f l e s s t h a n 1 . 1 2 5 a n d 0 . 6 2 5 d a y s f o r t h eM - U A S Ba n d t h es y s t e m , r e s p e c t i v e l y .T h eC H4 g a s p r o d u c t i o n w a s r e d u c e d t o l e s s t h a n5 0%o f t h e t h e o r e t i c a l v a l u e , w i t he f f l u e n tC O D a n dt o t a l V F A l e v e l so f 9 , 5 3 5 m g / La n d 3 , 7 5 0 m g f L a s H A c , r e s p e c t i v e l y .( 6 ) .T h e M - U A S B r e c o v e r e d e x p o n e n t i a l l ya f t e r f a i l u r e ,w i t ha n i n c r e a s ei n H R T( l o a d i n gr e d u c t i o n ) , i n t e r m so f C O Dr e m o v a le f f i c i e n c y , b u t l o g a r i t h m i c a l l y w i t hr e s p e c tt oC H4 g a s p r o d u c t i o n a s f o l l o w s :Y= 2 5 . 3 7 e °Y l= 9 . 2 5 + 6 4 . 0 1 I n X lw h e r eY = % s o l u b l e C O D r e m o v a le f f i c i e n c yX = H R T ( M - U A S B ) , d a y sY l = C H4 g a s p r o d u c t i o n ,L i dX l = H R T( M - U A S B ) , d a y sT h es y s t e m r e t u r n e d t o i t s i n i t i a ls t a g e o f o p e r a t i o nb y at w o - s t e pi n c r e a s ei nt h eH R T M U A S B ,b y1 . 5 a n d 5 . 8 t i m e s t h a to f t h e f a i l u r e H R T v a l u e ( w i t ha d i m e n s i o n a lt i m eo f 5 . 6 0 a n d 1 0f o r t h e M - U A S Ba n d t h e o v e r a l l s y s t e m ,r e s p e c t i v e l y ) .S h o c k - l o a d ss e e m e d t o s t i m u l a t et h e A - U A S B ’ sa c t i v i t y d u r i n g t h es y s t e m r e c o v e r y ; h o w e v e r ,t h e r ew a sn o a p p a r e n te f f e c t o n t h eM - U A S B , a f t e r i t h a s f a i l e dc o m p l e t e l y . T h e r e c o v e r ya p p r o a c h ,e m p l o y i n g s t e p - l o a d i n gr e d u c t i o na n d i n t e r n a lR R , a p p e a r s t o b e c o m p a r a b l et or e - a c c l i m a t i z a t i o n ,i n t e r m so f t i m e r e q u i r e m e n t s( b o t h n e e d4 - 5w e e k st o c o m p l e t e1 3 6t h ep r o c e s s e s)f o rr e c o v e r y . H o w e v e r ,t h e r e c o v e r ya p p r o a c h h a s s o m e a d v a n t a g e s ,i nt e r m so fs i m p l i c i t y o f o p e r a t i o na n d p r a c t i c a l i t y , a sa p p l i e dt o a f u l l - s c a l ep l a n t .( 7 ) . T h e o p t i m u mH R T f o r A - U A S B w a s1 . 0 ( 0 . 9 7 ) d a y s , w h e r e a st h e H R Tf o r t h e MU A S B w i t hr e s p e c t t oC O D r e m o v a l e f f i c i e n c ya n d C H4 g a sp r o d u c t i o n d u r i n g t h em a x i m i z a t i o na n d r e c o v e r y p e r i o d w a s2 . 0 a n d 2 . 7 d a y s , r e s p e c t i v e l y .T h i s s e e m st o i m p l ya r e s t r u c t u r i n go f b a c t e r i a l c o m m u n i t yi n s i d e t h e M - U A S B ,d u r i n g t h e r e c o v e r yp e r i o d .F o r d e s i g np u r p o s e s ,o p t i m u mo p e r a t i n g H R T so f 1 a n d 2 d a y s , a sw e l la s R Ro f 1 . 6 a n d2 . 5t i m e s t h e i n f l u e n tf l o w r a t e ,a r e r e c o m m e n d e df o r A - a n dM - U A S Br e a c t o r s ,r e s p e c t i v e l y .( 8 ) T h eo p t i m u mH R T A U A S B / H R T M U A S Br a t i o w a sa b o u t 0 . 6 0 w h i l et h eH R T AU A S B / ’ H ” T s y s t e mw a s0 . 4 0 , a p p l i e dt o t h e t w o - p h a s ea n a e r o b i c d i g e s t i o no f s e w a g e s l u d g e( U A S B - U A S B ) .T h e r e a c t o rd i a m e t e r t o h e i g h t r a t i oi s r e c o m m e n d e da t 1 : 8t o 1 : 1 0 , w i t hah y d r a u l i cl o a d i n gr a t e o f 0 . 5 5m3/ m 3 - d ( e q u i v a l e n t t o 1 9 k g C O D( t o t a l ) / m3-d a t3 5 Ca n dt h e S R 8 O / 2 0a n d R R 2 / 3 ) .6 . 2R E C O M M E N D A T I O N SF u t u r er e s e a r c hn e e d s a r e r e c o m m e n d e di n t h e f o l l o w i n ga r e a s :( 1 ) .R e b u i l d i n gab e n c h - s c a l e ,t w o - p h a s eU A S B - U A S Bp r o c e s sa c c o r d i n gt ot h em o d i f i e d1 3 7d e s i g n e dc r i t e r i a ,i s h i g h l y r e c o m m e n d e d .E v a l u a t i o no fs y s t e m f e a s i b i l i t y a n de f f e c t i v e n e s sw i t h a c t u a ls l u d g e ,o p e r a t i n ga t t h e o p t i m u mc o n d i t i o ni s a l s o n e c e s s a r y .( 2 ) . O r g a n i cs h o c kl o a d i n g a n dt o x i cs p i k i n go f t h e s y s t e ms h o u l d b ei n v e s t i g a t e d ;t h i s c a np r o v i d ea d d i t i o n a l i n f o r m a t i o ni n u n d e r s t a n d i n gh o wt h es y s t e m r e s p o n d s u n d e rs u c hc i r c u m s t a n c e sa n dt h e d e g r e eo fs u s c e p t i b i l i t y .( 3 ) .I n v e s t i g a t i n gt h et e m p e r a t u r ee f f e c t so nt h ep r o c e s sp e r f o r m a n c eb yk e e p i n gt h et e m p e r a t u r eo ft h eA - U A S Ba n d M - U A S Ba t2 0 a n d 3 5°Cr e s p e c t i v e l y ,i s a ni n t e r e s t i n ga r e ao f f u r t h e rr e s e a r c h .T h i s m a yh e l pr e d u c et h e c o s to fr e a c t o rh e a t i n g .( 4 ) .R e c i r c u l a t i o n o ft h e w a s t e ds l u d g e f r o mt h eA - U A S B ,a s a w h o l e o rp a r t , i n t ot h eM - U A S Bi sw o r t hi n v e s t i g a t i n g ;i t m a yr e d u c et h ea m o u n to f s l u d g e t ob e d i s p o s e d o f .H o w e v e r ,i tc o u l d a l s o r e d u c e t h ee f f i c i e n c yo f t h eM - U A S B .( 5 ) .T h e e f f e c to f t h ei n t e r n a lR Ra n ds t e p - l o a d i n gr e d u c t i o no nt h eo p t i m u m“ b e s tK n o w n ”r u n n i n gc o n d i t i o nf o rs y s t e m r e c o v e r yf r o mf a i l u r e ,s h o u l db er e - e v a l u a t e db ye m p l o y i n ga2 b y 2 f a c t o r i a ld e s i g ne x p e r i m e n t .( 6 ) .T r e a t i n gt h e d o m e s t i cw a s t e w a t e rd i r e c t l yb y u s i n gt h i sm o d i f i e dp r o c e s sc o n f i g u r a t i o ni s h i g h l yr e c o m m e n d e d .T h e i d e ai s t o e v a l u a t et h ef e a s i b i l i t ya n de f f e c t i v e n e s so f t h es y s t e m ,a st o w h e t h e ro r n o ti t c a nt e m p o r a r i l ys e r v ea s a m a i n1 3 8s t r e a mt r e a t m e n t f a c i l i t y , i n c a s eo f ap r o c e s s i n t e r r u p t i o no r f a i l u r e . I f s u c c e s s f u l , t h e na b y - p a s so f t h ei n f l u e n tw a s t e w a t e rc o u l dt h e n b et e m p o r a r i l y r e - d i r e c t e dt h r o u g h t h et w o - p h a s es y s t e m .( 7 ) E v a l u a t i n gt h ee f f e c to f s l u d g e r e c y c l i n g o nt h ep r o c e s sp e r f o r m a n c e .T h i s m a yi n d i c a t e w h e t h e rt h e r e i s a n y n e g a t i v ei m p a c t o n s y s t e m p e r f o r m a n c er e l a t e d t o s o l i d sr e c y c l i n go r n o t .1 3 9R E F E R E N C E SA n d e r s o n , G . K . , D o n n e l l y , T . , ( 1 9 7 8 )“ A n a e r o b i c C o n t a c t D i g e s t i o n f o r T r e a t i n gH i g h -S t r e n g t h S o l u b l e W a s t e s ” ,I n : M a t t o c k , G . ( e d . ) N e w p r o c e s s e so fw a s t e w a t e rt r e a t m e n t a n d r e c o v e r y ,E l l i sH o r w o o d ,C h i c h e s t e r , p . 7 5 .A n d r e w , J . W . ,( 1 9 6 8 ) “ A M a t h e m a t i c a lM o d e l f o r t h e C o n t i n u o u sC u l t u r e o fM i c r o o r g a n i s m sU t i l i z i n g I n h i b i t o r y S u b s t a n c e s ” , B i o t e c h .B i o e n g . ,j Q ,7 0 7 - 7 2 3 .A n d r e w ,J . F . , a n d P e a r s o n , E . A . , ( 1 9 6 5 )“ K i n e t i c s a n d C h a r a c t e r i s t i c s o f V o l a t i l eA c i dP r o d u c t i o n i n A n a e r o b i c F e r m e n t a t i o nP r o c e s s e s ” , I n t l . J o u r . A i r a n d W a t e rP o l l .( G . B . ) ,9 , 4 3 9 .A s i n a r iD i S a n M a r g a n o , C M ,( 1 9 8 1 )“ V o l a t i l eF a t t y A c i d s ,A n I m p o r t a n t S t a t eP a r a m e t e r f o r t h eC o n t r o l o f t h e R e l i a b i l i t y a n d t h e P r o d u c t i v i t i e so f M e t h a n eA n a e r o b i cD i g e s t i o n s ” , B i o m a s s , 1 , 4 7 - 5 9B e r g m a n , R . D . , ( 1 9 6 6 )“ A n a e r o b i c S l u d g e D i g e s t i o n- M O P 1 6 ” , J .W P C F ,3 8 , 7 1 7 - 7 2 1 .B a r r e t t e , O . J . ,( 1 9 5 2 ) “ R e p o r t o n t h e O p e r a t i o na n d M a i n t e n a n c e o f t h e W a t e r l y S e w a g eT r e a t m e n t P l a n t - C l e v e l a n d ,O h i o ” , S e w a g ea n d I n d u s t r i a lW a s t e s ,4 ,1 4 2 7 .B e n e f i e l d ,L . D . , a n dC . W .R a n d a l l ,( 1 9 8 0 ) “ B i o l o g i c a l P r o c e s s D e s i g n f o r W a s t e w a t e rP r o c e s s T r e a t m e n t ” , P r a c t i c e - H a l l ,I n c . , N . J . , 5 2 6 p p .B o x ,G . E . P . , ( 1 9 6 9 )“ E v o l u t i o n a r yO p e r a t i o n ” ,J o h n W i l e y & S o n s ,I n c . , N . Y . , U . S . A .B r u c e ,A . , ( 1 9 8 4 ) “ S e w a g e S l u d g eS t a b i l i z a t i o n a n d D i s i n f e c t i o n ” ,E l l i s H o r w o o d L i m i t e d ,C h i c h e s t e r , E n g l a n d .B u i j i s , J . W . ,( 1 9 8 1 ) “ M o d e l l i n g a n d S c a l e - u p o f A n a e r o b i c C o n v e r s i o no f D i s s o l v e d F a t t yA c i d s ” , A d v a n c ei n B i o t e c h n o l o g y , I . M . M o o - Y o u n ga n d R o b i n s o n , C . W . ,P e r g a m o n ,N . Y . , 5 2 9p p .B u i j i s , C . , ( 1 9 8 2 ) “ D i s t r i b u t i o na n d B e h a v o i ro f s l u d g e i n U p f l o w R e a c t o rf o r A n a e r o b i cT r e a t m e n to fW a s t e w a t e r ” ,B i o t e c h .B i o e n g . ,4 ,1 9 7 5 .B u l l , M . A . ,( 1 9 8 4 ) “ A n E v a l u a t i o no f S i n g l e - a n d S e p a r a t e - P h a s eA n a e r o b i c m d . W a s t eT r e a t m e n ti n F l u i d i z e d B e dR e a c t o r ” , B i o t e c h . B i o e n g . ,2 6 , 1 0 5 4 .C a i l , R . G . ,a n d e t a l . , ( 1 9 8 6 )“ T h eD e v e l o p m e n to f G r a n u l a t i o ni n a n U p f l o wF l o cD i g e s t e r a n da n U A S B T r e a t i n gC a n e J u i c e S t i l l a g e ” B i o t e c h n o l o g yL e t t e r s ,7 ,4 9 3 - 4 9 8 .1 4 0C a l l e n d e r ,I . J . , e t a l . , ( 1 9 8 3 ) “ R e c e n t A d v a n c ei n A n a e r o b i c D i g e s t i o n T e c h n o l o g y ” ,P r o c e s s B i o c h e m . , 1 8 ( 4 ) , 2 4 - 3 7 .C a p r i , M . G . ,( 1 9 7 5 ) “ p H a d j u s t m e n t i n A n a e r o b i c D i g e s t i o n ” , W a t . R e s . , , 3 0 7 - 31 3 .C h a n g ,T . C . ,W u ,Y . C . , a n d e t . a l , ( 1 9 8 9 ) “ A n a e r o b i cS l u d g e D i g e s t i o n U s i n gT h e r m o p h i l i c P h a s eS e p a r a t i o n ” , J . C h e m . T e c h . B i o t e c h n o l . , 4 5 ,3 3 5 - 3 3 7 .C h e n ,Y . R . , H a s h i m o t o , A . G . , ( 1 9 7 8 ) “ K i n e t i c s o f M e t h a n eF e r m e n t a t i o n ” , B i o t e c h n o l o g yB i o e n g i n e e r i n g S v m p . , , 2 6 9 - 2 8 2 .C h i u - Y u e , L i n , ( 1 9 8 6 ) “ M e t h a n o g e n i cD i g e s t i o n U s i n g M i x e d S u b s t r a t eo fA c e t i c ,P r o p i o n i c , a n dB u t y r i c A c i d s ” ,W a t .R e s . , ( 3 ) , 3 8 5 - 3 9 4 .C h o a t e , W . T . , a n d e t a l . ,( 1 9 8 2 ) “ M e m b r a n e - E n h a n c e d A n a e r o b i c D i g e s t e r s ” P r o c . 3 7 t hI n d u s t r i a l W a s t e C o n f e r . , P u r d u e U n i v . ,I n d i a n a , 6 6 1 - 6 6 6 .C h r i s t e n s e n ,D . R . , G e r i c k , J . A . , ( 1 9 8 4 ) “ D e s i g n a n d O p e r a t i o no f a nU p f l o wA n a e r o b i cS l u d g e B l a n k e t R e a c t o r ” ,W P C F ,5 6 ( 9 ) , 1 0 5 9 - 1 0 6 2 .C h u n g ,K . T . , ( 1 9 7 6 ) “ I n h i b i t o r y E f f e c t so f H2 o ng r o w t ho f C l o s t r i d i u m c e l l o b i o p a r u m ”A p p i . e n v i r . M i c r o b i o l . , 3 1 , 3 4 2 - 3 4 8 .C o h e n , A . , e t a l . ,( 1 9 7 9 ) “ I n f l u e n c e o f P h a s e S e p a r a t i o n o n t h eA n a e r o b i c D i g e s t i o n o fG l u c o s e - I : M a x i m u m C O D T u r n o v e r R a t e d u r i n gC o n t i n u o u s O p e r a t i o n ” ,W a t .j ,5 7 1 .C o h e n ,A . , e t . a l , ( 1 9 8 3 ) “ T w o - P h a s e D i g e s t i o no fL i q u i da n d S o l i d w a s t e s ” , P r o c . 3 r dI n t e r . S v m p . o n A n a e r o . D i g e s t . , B o s t o n ,U S A , 1 2 3 - 1 3 8 .C o l l e r a n ,E . , a n d e t a l . , ( 1 9 8 3 ) “ O n ea n dT w o - S t a g eA n a e r o b i c d i g e s t i o no f A g r i c u l t u r a lW a s t e s ”P r o c . o f t h e 3 r d I n t e r n a t i o n a lS y m p o s i u m o n A n a e r o b i cD i g e s t i o n ,B o s t o n , U S A .C o r t i n o v i s ,D . , ( 1 9 8 4 ) “ C o n t r o l l i n g W a s t e w a t e rT r e a t m e n t P r o c e s s e s ” ,R i d g e L i n e P r e s s ,C a l i f o r n i a ,U . S . A .D a t t a ,R . K . , ( 1 9 8 1 ) “ A c i d o g e n i cF e r m e n t a t i o n o fC o r nS t o v e r ”B i o t e c h . B i o e n g . ,2 3 , 6 1 ,D i c h t l ,N . J . , ( 1 9 8 7 ) “ T w o S t a g eS l u d g e S t a b i l i z a t i o n ” W a t .S c i . T e c h n o l . ,j( 7 ) , 1 2 4 7 -1 2 5 0 .D i n o p o u l o u ,G , a n d L e s t e r , J . N . ,( 1 9 8 9 ) “ O p t i m i z a t i o no f a T w o - p h a s eA n a e r o b i cD i g e s t i o n S y s t e mT r e a t i n g aC o m p l e x W a s t e w a t e r ” , E n v . T e c h . L e t t .j Q ,7 9 9 - 8 1 4 .1 4 1D o l f i n g ,J . , 1 9 8 6 ,“ G r a n u l a t i o n i n U A S BR e a c t o r ” W a t . S c i . T e c h . ,j( 1 2 ) , 1 5 - 2 5 .E a s t m a n , J . A . , a n d F e r g u s o n , J . F . ,( 1 9 8 1 )“ S o l u b i l i z a t i o n o f P a r t i c u l a t eO r g a n i c C a r b o nd u r i n g t h e A c i d P h a s eo f A n a e r o b i c D i g e s t i o n ” , J .W P C F ,( 3 ) , 3 5 2 - 3 6 5 .E n e m a , P . A . G . ,P o l a n c o , F . F . , ( 1 9 8 7 )“ B e h a v i o u ro fa n a e r o b i ce x p a n d e d b e d r e a c t o r i nn o n - s t e a d y s t a t e c o n d i t i o n s ” ,W a t . R e s . ( 1 1 ) , 1 3 2 9 - 1 3 3 4 .F a n n i n , K . F .e t . a l , ( 1 9 8 1 - 1 9 8 3 ) “ A n a e r o b i cP r o c e s s ” ,J .W P C FL i t e r a t u r e R e v i e w I s s u e ,, 5 3 - 5 5 .F i s h e r ,A . J . ,( 1 9 3 4 )“ D i g e s t o r O v e r f l o wL i q u o r : I t s C h a r a c t e ra n d E f f e c to nP l a n tO p e r a t i o n ” ,S e w a g e W o r k s ,6 , 9 3 4 .F o n g s a t i t k u l ,P . , ( 1 9 8 6 )“ A P r e l i m i n a r y R e p o r t :A nA s s e s s m e n to f W a s t e w a t e r T r e a t m e n tS y s t e m P r a c t i c a l l yU s e d i nT h a i l a n d ” ,C I D A H o m eA t t a c h m e n tP r o g r a m .G h o s h ,S . , a n d H e n r y ,M . P . , ( 1 9 8 1 )“ S t a b i l i z a t i o na n dG a s i f i c a t i o no f S o f tD r i n kM a n u f a c t u r i n gW a s t e b y C o n v e n t i o n a la n d T w o - P h a s e A n a e r o b i c D i g e s t i o n ”P r o c .o ft h e 3 6 t h P u r d u e I n d u s t r i a l W a s t e C o n f e r e n c e ,L a f a y e t t e ,I N ,2 9 2 .G h o s h , S . , a n d e t a l . , ( 1 9 8 3 a ) “ M e t h a n eP r o d u c t i o n f r o mI n d u s t r i a lW a s t e sb yT w o - P h a s eA n a e r o b i cD i g e s t i o n ” P r o c . o f t h e 6 t hS y m p o s i u m o n B i o m a s sa n d W a s t e s ,O r l a n d o ,F L . , U S A .G h o s h ,S . , a n d e t a ! ,( 1 9 8 3 b )“ T w o - s t a g e U p f l o wA n a e r o b i cD i g e s t i o n o f C o n c e n t r a t e dS l u d g e ”P r o c . o f t h e5 t h S m p o s i u m o n B i o t e c h n o l o g y f o r F u e l sa n d C h e m i c a l s ,G a t l i n b u r g ,T N .G h o s h , S . , ( 1 9 8 4 )“ A d v a n c e T w o - P h a s eD i g e s t i o no fS e w a g eS l u d g e ” ,S y m p . o n E n e r g yf r o m B i o m a s sa n d W a s t e V I I I , L a k eB u e n a , V i s t a , F l o r i d a ,U S A ,, 8 3 5 - 8 7 4p p .G h o s h ,S . , ( 1 9 8 7 )“ I m p r o v e dS l u d g e G a s i f i c a t i o nb yT w o - P h a s eA n a e r o b i c D i g e s t i o n ”J . E n v i r . E n g .D i v . ,1 1 3 ( 6 ) ,1 2 6 5 - 1 2 8 4 .G l o y n a ,E . F . , ( 1 9 8 2 )“ A n A n a l y s i so f r e s e a r c h N e e d sc o n c e r n i n gt h e T r e a t m e n t ,U t i l i z a t i o n ,a n d D i s p o s a lo f W a s t e w a t e rt r e a t m e n tP l a n tS l u d g e ” , W P C FH i g h l i g h t s ,. 1 2( 7 ) .G r a e f ,S . P . a n d A n d r e w ,J . F . ,( 1 9 7 4 a )“ S t a b i l i t y a n d C o n t r o lo f A n a e r o b i cD i g e s t i o n ” ,j .W P C F ,4 6 , 6 6 6 - 6 8 3 .G r a e f ,S . P . ,a n dA n d r e w , J . F . ,( 1 9 7 4 b ) “ M a t h e m a t i c a lM o d e l a n dC o n t r o l o f A n a e r o b i cD i g e s t i o n ”A I C h ES y m p o s i u mS e r i e s , 7 0 ,( 1 3 6 ) , 1 0 1 - 1 3 1 .1 4 2G u j e r , W . ,a n d Z e h n d e r ,A . J . B . ,( 1 9 8 3 ) “ P a t h w a yo f A n a e r o b i c D i g e s t i o n ” ,W a t .S c i . T e c h . , , 1 2 7 .H a m o d a ,M . F . ,a n d e t a l . ,( 1 9 8 4 ) “ E f f e c t o f S e t t l i n go n P e r f o r m a n c eo f t h e U p f l o wA n a e r o b i cS l u d g e B e dR e a c t o r s ”W a t . R e s . ,1 2 , 1 5 6 1 - 1 5 6 7 .H a r p e r ,S . R . ,a n d e t a l ,( 1 9 8 6 ) “ B i o t e c h n o l o g yR e p o r t :R e c e n tD e v e l o p m e n t si nH y d r o g e nM a n a g e m e n tD u r i n gA n a e r o b i cB i o l o g i c a l W a s t e w a t e rT r e a t m e n t ” ,B i o t e c h . B i o e n g . ,( 4 ) , 5 8 5 - 6 0 2 .H e e r t j e s ,P . M . , ( 1 9 7 8 )“ D y n a m i co f L i q u i dF l o w i na nU p f l o wR e a c t o ru s e d f o rA n a e r o b i cT r e a t m e n to fW a s t e w a t e r ” ,B i o t e c h .B i o e n g . ,Q ,1 5 7 7 .H e e r t j e s ,P . M . ,( 1 9 8 2 ) “ F l u i d F l o wi n U p f l o wR e a c t o r f o rA n a e r o b i cT r e a t m e n to fB e e tS u g a r F a c t o r yW a s t e w a t e r ” ,B i o t e c h .B i o e n g . ,2 4 , 4 4 3 .H i c k e y ,R . F . ,V a n d e r w i e l e n ,J . , a n d S w t z e n b a u m ,M . S . ,( 1 9 8 7 ) “ T h e E f f e c t so f O r g a n i cT o x i c a n t so nM e t h a n eP r o d u c t i o na n d H y d r o g e nG a sl e v e l sd u r i n g t h eA n a e r o b i cD i g e s t i o no f W a s t eA c t i v a t e dS l u d g e ”W a t .R e s . , 2 1 ( 1 1 ) , 1 4 1 7 - 1 4 2 7 .H u l s o f f - P o l ,L . W . ,d e Z e e u w . W . J . ,e t . a l ,( 1 9 8 3 ) “ G r a n u l a t i o ni nU A S B - r e a c t o r s ” ,W a t . S c i . T e c h n o l ,1 5 ,2 9 1 .H u l s o f f - P o l ,L . W . ,e t a l ,( 1 9 8 6 ) “ N e wT e c h n o l o g i e sf o r A n a e r o b i cW a s t e w a t e rT r e a t m e n t ” ,W a t .S c i .T e c h . ,1 8 , ( 1 2 ) , 4 1 - 5 3 .J a m e ,R . W . ,( 1 9 7 6 ) “ S e w a g eS l u d g e T r e a t m e n ta n dD i s p o s a l ” ,N o y e s D a t a C o r p o r a t i o n ,N e w J e r s e yU S A ,3 3 9p p .J e r i s ,J . S . , a n dM c C a r t y , P . L . ,( 1 9 6 5 ) “ T h eB i o c h e m i s t r yo f m e t h a n ef e r m e n t a t i o nu s i n gC ’4 t r a c e r s ”J .W P C F ,7 ,1 7 8 - 1 9 2 .K a s p e r ,H . F . , a n dW u h r m a n n ,K . , ( 1 9 7 8 ) “ K i n e t i cP a r a m e t e r sa n d R e l a t i v eT u r n o v e rs o m eI m p o r t a n t C a t a b o l i cR e a c t i o n si n D i g e s t i n gs l u d g e ”A p p l .e n v i r .M i c r o b i o l, 1 - 7 .K e e n a n ,J . D . ,( 1 9 7 6 )“ M u l t i p l e S t a g e dR e c o v e r yf r o m S o l i dW a s t e s ”J .E n v i r o n .S c i .H e a l t h , A l l( 8 / 9 ) , 5 2 5 .K e l e t i ,G . , e ta l ,( 1 9 7 4 ) “ H a n d b o o ko fM i c r o m e t h o d sf o r t h e B i o l o g i c a lS c i e n c e ” ,V a nN o s t r a n dR e i n h o l dI n c . ,N . Y . , U S A .K l a p w i j k ,A . ,e t a l ,( 1 9 8 1 )“ D e n i t r i f i c a t i o no f d o m e s t i cw a s t e w a t e ri n a n u p f l o ws l u d g eb l a n k e t r e a c t o rw i t h o u tc a r r i e r m a t e r i a lf o r t h e b i o m a s s ”I n : C o o p e rP F , A t k i n s o n1 4 3B( e d s )F l u i d i s e d b e dt r e a t m e n t o fw a t e ra n d w a s t e w a t e r .E l l i sH o r w o o d ,C h i c h e s t e r , p . 2 O5K u g e l m a n ,I . J . a n d J e r i s , J . S . , ( 1 9 8 1 )“ S l u d g eT r e a t m e n tA n a e r o b i c D i g e s t i o n ” ,M a r c e l .D e k k e r , I n c . ,N . Y . , 5 9 1p p .L a w r e n c e ,A . W . , a n dM c C A r t y , P . L . ,( 1 9 7 0 )“ K i n e t i c so fM e t h a n e F e r m e n t a t i o ni nA n a e r o b i cT r e a t m e n t ” ,J . W P C F ,4 1 ,R 1 - R 1 6L e t t i n g a ,G . , ( 1 9 7 8 )“ T h e P r o s p e c t so f A n a e r o b i cW a s t e w a t e rT r e a t m e n t ” ,4 t h E u r o p e a nS e w a g ea n dR e f u s e S y m p . ,E A S ,M u n i c h . ,2 2 6 .L e t t i n g a ,G . ,V a n D e r G u s t , A . T h ,( 1 9 7 9 a )“ A n a e r o b i c T r e a t m e n to fM e t h a n o l i c W a s t e ” ,W a t .R e s . , 1 3 ,7 2 5 .L e t t i n g a ,G .V a n V e l s e n , a n d e t . a l ,( 1 9 7 9 b )“ F e a s i b i l i t yo ft h eU p f l o wA n a e r o b i c S l u d g eB l a n k e t ( U A S B ) - P r o c e s s ” ,P r o c . N a t . C o n f . o nE n v i r o n . E n g . , A S C E ,S a nF r a n c i s c o ,U S A ,3 5 - 4 5 .L e t t i n g a ,G . e t a l ,( 1 9 8 0 )“ U s eo fU p f l o wS l u d g e B l a n k e t( U S B )R e a c t o rC o n c e p t f o rB i o l o g i c a lW a s t e w a t e rT r e a t m e n t , E s p e c i a l l yf o r A n a e r o b i cT r e a t m e n t ” ,B i o t e c h .B i o e n g . ,2 2 ,6 9 9 - 7 3 4 .L e t t i n g a ,G . , H o b m a ,S . W . ,a n d e t . a l ,( 1 9 8 3 a )“ D e s i g n ,o p e r a t i o n , a n d e c o n o m yo fa n a e r o b i c t r e a t m e n t ” , W a t .S c i . T e c h . ,1 5 , 1 7 7 - 1 9 5 .L e t t i n g a ,G . ,R o e r s m a ,R . , a n dG r i n , P . ,( 1 9 8 3 b ) “ A n a e r o b i cT r e a t m e n t o f R a wD o m e s t i cS e w a g ea ta m b i e n tt e m p e r a t u r eu s i n ga g r a n u l a rb e dU A S BR e a c t o r ” B i o t e c h .B i o e n g . , ,2 5 ,1 7 0 1 - 1 7 2 3 .L e t t i n g a ,G . , H u i s h o f f ,P o l ,e t a l ,( 1 9 8 3 c )“ U p f l o wS l u d g e B l a n k e tP r o c e s s ” ,P r o c .3 r dI n t e r .S y m p .o n A n a e r o b i cD i g e s t i o n ,B o s t o n ,U S A , 1 3 9 - 1 5 8 .L e t t i n g a ,G . ,H u i s h o f f ,P o l , e t a l ,( 1 9 8 6 ) “ A d v a n c e dR e a c t o rD e s i g n ,O p e r a t i o na n dE c o n o m y ” ,W a t .S c i . T e c h . ,1 8( 1 2 ) ,9 9 - 1 0 8 .M a a t , D . Z . ,a n dH a r b e t s ,L . H . A . ,( 1 9 8 7 ) “ T h eU p f l o wA n a e r o b i cS l u d g eB l a n k e tW a s t e w a t e rT r e a t m e n tS y s t e m :AT e c h n o l o g yR e v i e w ” , P u I p & P a p e rC a n a d a ,( 1 1 ) .M a h o n e y ,E . M . ,V a r a n g u ,L . K . ,C a i r n s ,W . L . ,( 1 9 8 7 ) “ T h eE f f e c to f C a l c i u mo nM i c r o b i a lA g g r e g a t i o nd u r i n g U A S BR e a c t o rS t a r t - U p“ W a t .S c i .T e c h . ,1 9 , 2 4 9 -2 6 0 .1 4 4M a l i n a , J . F . , ( 1 9 8 0 )“ A n a e r o b i cW a s t e T r e a t m e n t ” ,L e c t u r e N o t e ,U n i v .o f T e x a s( A u s t i n ) .M a s s e y ,M . C . a n dP o h i a n d F . G . , ( 1 9 7 8 )“ P h a s e S e p a r a t i o no f A n a e r o b i cS t a b i l i z a t i o nb yK i n e t i cC o n t r o l s ” ,J . W P C F ,5 0 ,2 2 0 4 .M c C a r t y ,P . L . , ( 1 9 7 1 )“ E n e r g ya n d K i n e t i c so f A n a e r o b i cT r e a t m e n t ” ,A n a e r o b i cB i o . T r e a t . ,P r o c . A m e r .C h e m .S o c i e t y ,A d v a n c ei nC h e m i s t r y S e r i e s ,9 1 - 1 0 7 .M o n t g o m e r y ,C . D . ,( 1 9 8 4 )“ D e s i g na n d A n a l y s i so fE x p e r i m e n t s ” ,J o h nW i l e ya n d S o n s ,2 n d E d i t i o n .M o s e y , F . E . ,( 1 9 8 3 a ) “ M a t h e m a t i c a lM o d e l l i n go fA n a e r o b i cD i g e s t i o nP r o c e s s :R e g u l a t o r yM e c h a n i s m sf o r t h eF o r m a t i o no fS h o r t - C h a i nV o l a t i l eA c i d sf r o mG l u c o s e ”W a t e rS c i .T e c h n o l . ,1 5 ,2 0 9 - 2 3 2 .M o s e y ,F . E . ,( 1 9 8 3 b )“ K i n e t i cD e s c r i p t i o n so fA n a e r o b i cD i g e s t i o n ” , P r o c .3 r d I n t e r .s y m p .o nA n a e r o b i cD i g e s t i o n ,B o s t o n ,U S A ,3 7 - 5 2 .N o r m a n n ,J . ,a n dF r o s t e l l ,B . , ( 1 9 7 7 ) “ A n a e r o b i c W a s t e w a t e rT r e a t m e n t i naT w o - S t a g eR e a c t o ro fa N e wD e s i g n ”P r o c . o f t h e3 2 t h P u r d u eI n d u s t r i a lW a s t e C o n f e r e n c e ,3 8 7 .O l e s z k i e w i c z ,J . A . ,T h a d a n i ,V . J . ,( 1 9 8 8 )“ E f f e c t so fB i o f i l t e rM e d i ao nt h e P e r f o r m a n c eo fA n a e r o b i cH y b r i dR e a c t o r s ” ,E n v . T e c h . L e t t ,9 ,8 9 - 1 0 0 .O l t h o f ,M . ,( 1 9 8 2 )“ A n a e r o b i cT r e a t m e n to fI n d u s t r i a l W a s t e w a t e r s ”C h e m i c a lE n g i n e e r i n g ,( 2 3 ) , 1 2 1 - 1 2 6 .P A L N SS a m - s o o n ,e t a l ,( 1 9 8 7 )“ H y p o t h e s i sf o r P e l l e t i z a t i o ni n t h eU p f l o wA n a e r o b i cS l u d g eB e dR e a c t o r ” ,W a t e rS AV o l . 1 3 ,N o . 2 ,6 9 - 8 0 .P a t e l ,G . B . ,R o t h ,L . A . ,a n dS p r o t t ,G . D . ,( 1 9 7 9 )“ F a c t o r sI n f l u e n c i n gF i l a m e n tL e n g t ho fM e t h a n o s p i r i l l u mh u n g a t i i ”J . G e n .M i c r o b i o l . ,1 1 2 ,4 1 1 - 4 1 5 .P a v l o s t a t h i s ,S . G . , a n dG o s s e t t ,J . M . ,( 1 9 8 6 )“ AK i n e t i cM o d e lf o rA n a e r o b i cD i g e s t i o no f B i o l o g i c a lS l u d g e ” ,B i o t e c h .B i o e n g . , ,1 5 1 9 - 1 5 3 0 .P a v o n i ,J . L . ,T e n n e y ,M . W . ,e ta l , ( 1 9 7 2 )“ B a c t e r i a lE x o c e l l u l a rP o l y m e r sa n dB i o l o g i c a lF l o c c u l a t i o n ” ,J . W P C F4 4( 3 ) ,4 1 5 .P e r o t ,C . ,( 1 9 8 9 )“ O p t i m i z a t i o no fS l u d g eA n a e r o b i cD i g e s t i o nb yS e p a r a t i o no fH y d r o l y s i s - A c i d i f i c a t i o na n d M e t h a n o g e n e s i s ”E n v i r .T e c h n o l .L e t t e r . ,j Q ,6 3 3 - 6 4 4 .1 4 5P i p y n , P . , a n d e t a l . ,( 1 9 7 9 ) “ A P i l o t - s c a l eA n a e r o b i c U p f l o w R e a c t o rT r e a t i n g D i s t i l l e r yW a s t e w a t e r s ” ,B i o t e c h n o l . L e t t . ,1 , 4 9 5 .P o h l a n d , F . G . , a n dG h o s h , S . , ( 1 9 7 1 ) “ D e v e l o p m e n ti n A n a e r o b i cT r e a t m e n t P r o c e s s e s ” ,B i o t e c h .B i o e n g . S y m p . , , 8 5 - 1 0 6 .P o h l a n d ,F . G . a n d G h o s h , S . ,( 1 9 7 1 a ) “ D e v e l o p m e n ti n A n a e r o b i c S t a b i l i z a t i o no fO r g a n i cW a s t e- T h e T w o - P h a s eC o n c e p t ” , E n v . L e t t e r s ,. 1 ( 4 ) .P o h i a n d ,F . G . a n dM a s s e y , M . L . , ( 1 9 7 5 ) “ A nA p p l i c a t i o n o f P r o c e s sK i n e t i c s f o r P h a s eS e p a r a t i o n o f t h eA n a e r o b i c S t a b i l i z a t i o nP r o c e s s ” , P r o g r e s si n W a t .T e c h . , 7 ( 1 ) ,1 7 3 - 1 8 9 .R a j a n ,R . V . ,L i n J i h - G a w ,R a y, B . T . , ( 1 9 8 9 ) “ L o w - l e v e lc h e m i c a lp r e t r e a t m e n tf o re n h a n c e ds l u d g es o l u b i l i z a t i o n“ , J . W P C F ,j ,1 6 7 8 - 1 6 8 3 .R i j k e n s ,B . A . ,( 1 9 8 1 ) “ AN o v e lT w o - S t e pP r o c e s sf o r t h eA n a e r o b i c D i g e s t i o no f S o l i dW a s t e s ”P r o c . o f t h e5 t h S y m p o s i u mo nE n e r g y f r o m B i o m a s sa n d W a s t e s ,O r l a n d o ,F L , U S A , 4 6 3 - 4 7 5 .R i n z e m a ,A . , L e t t i n g a ,G . , ( 1 9 8 8 )“ T h e E f f e c to f S u i p h i d e o n t h e A n a e r o b i cD e g r a d a t i o no f P r o p i o n a t e ” ,E n v . T e c h . L e t t . ,9 ,8 3 - 8 8 .R i p l e y ,L . E . ,a n d B o y l e , W . C . ,( 1 9 8 3 ) , “ A n a e r o b i cD i g e s t i o n M o d e l s :I m p l i c a t i o nf o r t h ed e s i g ne n g i n e e r , P r o c . 3 r dI n t e r . S y m p . o n A n a e r o b i cD i g e s t i o n ,B o s t o n ,U S A ,4 5 1 - 4 6 3 .S c h e i f i n g e r ,C . C . ,L i n e h a n , B . , a n d W o l i n ,M . J . , ( 1 9 7 2 )“ H2 p r o d u c t i o nb y S e l e n o m o n a sr u m i n a n t i u mi n t h e a b s e n c ea n d p r e s e n c eo f m e t h a n o g e n i cb a c t e r i a ”A p p l .M i c r o b i o l . ,2 9 , 4 8 0 - 4 8 3 .S c h w a r t z ,L . J . , ( 1 9 8 2 )“ A n a e r o b i c D i g e s t i o na n dH e a t P u m p s :P o t e n t i a lf o r E n e r g yR e c o v e r yi n aW a s t eS t r e a m ” ,B i o t e c h .B i o e n g . S y m p . ,1 1 , 4 6 3 .S o u z a ,M . E . , ( 1 9 8 6 )“ C r i t e r i a f o r t h eU t i l i z a t i o n ,D e s i g na n dO p e r a t i o no f U A S BR e a c t o r ”W a t .S c i .T e c h . , ,1 8( 1 2 ) , 5 5 - 6 9 .S t r o n a c h ,L . J . , e t .a l ,( 1 9 8 6 ) ,i n I n d u s t r i a lW a s t e w a t e rT r e a t m e n t ” , S p r i n g e r - V e r l a g ,t I1 8 3p pT a v e r y ,M . A .e t a l ,( 1 9 7 9 )“ P h a s e S e p a r a t i o nT r e a t m e n t :S u r f a c t a n t - F o a m i n gP r o b l e m s ;S o l i d - L i q u i dS e p a r a t i o n ” , W a t e ra n d W a s t eE n g i n e e r i n g ,j( 2 ) , 4 7 .T h e r k e n s e n ,H . H . ,( 1 9 7 9 ) “ T h e r m o p h o l i cD i g e s t i o n o fa S t r o n g C o m p l e xS u b s t r a t e ” ,j1 4 6W P C F ,5 1 , 1 9 4 9 - 1 9 6 4 .T o r p e y ,W . N . ,( 1 9 5 5 ) “ L o a d i n gt o F a i l u r e o f a P i l o t H i g h - R a t eD i g e s t o r ” , S e w ,a n d m d .W a s t e s .2 7 ,1 2 1 .T r u d e l l , M . , V a n d e r B e r g ,L . , a n d e t . a l , ( 1 9 8 5 ) “ A n a e r o b i cT r e a t m e n to f H i g h - S t r e n g t hA c i d i cO r g a n i c W a s t e w a t e r sU t i l i z i n g t h e U p f l o wS l u d g e B l a n k e tT r e a t m e n tP r o c e s s ” , W a t e rP o l l . R e s . J o u r n a l( C A N A D A ) ,2 0 ( 1 ) , 2 5 - 4 1 .U S . E P A ,( 1 9 7 8 ) ,“ P r o c e s s D e s i g nM a n u a l f o r M u n i c i p a l S l u d g e L a n d f i l l ” ,E P A6 2 5 / 1 - 7 8 -0 1 0 . T e c h . T r a n s f .U S . E P A , ( 1 9 7 9 ) “ P r o c e s sD e s i g n M a n u a l f o r S l u d g eT r e a t m e n ta n d D i s p o s a l ” , E P A6 2 5 / 1 - 7 9 - 0 1 1 ,T e c h . T r a n s f .V a nD e rM e e r ,R . R . , ( 1 9 8 3 ) “ M a t h e m a t i c a lD e s c r i p t i o n o f A n a e r o b i cT r e a t m e n to fW a s t e w a t e ri nU p f l o wr e a c t o r ” , B i o t e c h .B i o e n g . , , 2 5 3 1 - 2 5 5 6 .V e s i l i n d ,P . A . , ( 1 9 8 0 )“ T r e a t m e n ta n d D i s p o s a l o f W a s t e w a t e rS l u d g e ” , A n n A r b o rS c i . ,M i c h i g a n , 3 2 3 p p .W i e g a n t ,W . W . ,a n d e ta l . ,( 1 9 8 5 ) “ G r a n u l a t i o n o fB i o m a s si n T h e r m o p h i l i c U p f l o wA n a e r o b i cS l u d g e B l a n k e tR e a c t o r sT r e a t i n g A c i d i f i e d W a s t e w a t e r s ”B i o t e c h .B i o e n g . , , 7 1 8 - 7 2 7 .W u .W e i - m i n ,e t . a l , ( 1 9 8 5 )“ P r o p e r t i e so f G r a n u l a rS l u d g ei nU p f l o wA n a e r o b i c S l u d g eB l a n k e tR e a c t o ra n d i t s F o r m a t i o n ” ,P r o c . 4 t hI n t e r . S y m p . o nA n a e r o b i cD i g e s t i o n .G u a n g z h o u ,C h i n a .Y a n , J i n g - Q i n g ,( 1 9 9 1 ) “ A n a e r o b i cD i g e s t i o no f C h e e s e W h e yi n A n U p f l o wA n a e r o b i cS l u d g e B l a n k e tR e a c t o r ” P h . dT h e s i s , U n i v . o fB r i t i s h C o l u m b i a ,C a n a d a .Z e e u w .D e W i l l e m ,( 1 9 8 0 ) “ A c c l i m a t i z a t i o no fD i g e s t e dS e w a g eS l u d g eD u r i n g S t a r t - U Po f A n U p f l o wA n a e r o b i cS l u d g e B l a n k e t( U A S B ) R e a c t o r ” ,P r o c . 3 5 t hP u r d u e .I n d .W a s t eC o n f e r e n c e ,3 9 - 4 7 .Z i e k e f o o s e ,C . , ( 1 9 7 6 ) “ O p e r a t i o n sM a n u a l - A n a e r o b i cS l u d g e D i g e s t i o n ” ,E P A4 3 0 / g - 7 6 -0 0 1 , U S . E P A ,W a s h i n g t o n ,D . C . , U . S . A .Z o e t e m e i j e r ,R . J . , ( 1 9 8 2 )“ A c i d o g e n e s i so fS o l u b l eC a r b o h y d r a t e - C o n t a i n i n gW a s t e w a t e r ,P h . DT h e s i s , U n i v .o f A m s t e r d a m ,T h e N e t h e r l a n d s .Z o e t e m e i j e r ,R . J . e t . a l ,( 1 9 8 2 ) “ p H I n f l u e n c eo n A c i d o g e n i cD i s s i m i l a t i o no f G l u c o s ei na n A n a e r o b i cD i g e s t i o n ” ,W a t .R e s . 1 6 , 3 0 3 - 3 1 1 .1 4 7A P P E N D I XAS y n t h e t i cS l u d g eP r e p a r a t i o na n d S y s t e mS e t - u pA L l:S u m m a r y o f R e s e a r c hP r o b l e m s / R e m e d i a lA c t i o n s / S c o p ea n dA p p r o a c hM o d i f i c a t i o n sA 2 . 1:S y s t e mS e e d i n ga n dL o a d i n gR a t eA 2 . 2 :F i n a l C o n s t i t u e n t so f P r i m a r ya n d S e c o n d a r y S y n t h e t i cS l u d g e s a n dC h e m i c a lA n a l y s i so f D o gf o o d sA 3 . 1:D e t a i l e dS i z i n g o fA c i d -a n dM e t h a n e - P h a s eR e a c t o r s( U A S B - U A S B )A 3 . 2:S p r e a d - s h e e tf o rS i z i n go f t h eA c i d -a n dM e t h a n e - P h a s eR e a c t o r s( U A S B - U A S B )A 4 . 1:D e v e l o p m e n to f A S m a l l - S c a l e( 1 - L i t r e ) S y n t h e t i cS l u d g eP r e p a r a t i o nA 4 . 2 : D e v e l o p m e n to fAS c a l e - U p( 3 0 - L i t r e )S y n t h e t i cS l u d g e P r e p a r a t i o nA 5 . 1: M o n i t o r i n gt h eC h a r a c t e r i s t i c so f P r i m a r yS y n t h e t i cS l u d g eP r e p a r e dT h r o u g h o u tt h eE x p e r i m e n tA 5 . 2 :M o n i t o r i n gt h eC h a r a c t e r i s t i c so f S e c o n d a r yS y n t h e t i cS l u d g e P r e p a r e dT h r o u g h o u tt h eE x p e r i m e n tLiable11SummaryofResearchProblems/RemedialActions/ScopeancippfoachsMoiifcatIonPhase/durationResearchproblems andconceptual ideasRemedial actionsandmodificationsoftheoriginalproposaloftheresearchworks*IProposalprepazahonCompof erliteraturesearchon:sewagesludge;AgreewiththeapproachTwo-phaseanaerobicdigcshori;UASSOplineebothobicdrresintermsoil:Anaerobicdigestionobicctaes:Systemremoval clliciencyPofutioncontrolCH4contentandproductionEnergyrecoveryControl tcm@35degreeCandProblemareas:pH@517brA-andM-UASBsPoorsupcmataritqualityReplicalo-BuildmoreUASBandrunparalelyLowCH4contentandproductionBid.costproblemsHydrolysisratelimitingstepOptionally. comparisonofactual C114productionFlowandIcedisscns.livctoLIASOintermsof%theorcliealCH4productionEttedoftemperatureandpt1(>0.4-OK)Approaches:Syntheticskidge-asoidloiiieunavailabilityHRTIRR/SRMixingStratI-scaledwithnjbbcr!o-nngMicingspeedoperateunder walerlevelSuscwplibildylrccoveryperiodSummarizeproblemareaslapproachTwo-phaseIJASB-UASBequipmentrcqdkostostitnalionKineticsinthetonnofresearchproposalSpCciliccontrololpllftcnrp.ZProposaiDefenseSpeciecontrolofpelifemp.2-3considerableparameterssheukibeenoughOptimaloperatingconditions:Firstslopvarinblcscoukintremain222tactorixi design:constantappliedtosecondstepFWSIslop-FWSRimixingspeed77Y.theoreticalC1l41??Secondstep-RRlwaslinaJmriiriglime(Or.Olciham)Overal processpertormancos:Analyticalmethodfor sludgecarbohydrateRerunopl.nmngcorwi.(Dr.KJlaFeeddirectlyfromPnandSec.sludgesTimecorretraudfnostudyonmodellingMax.toadiogrccovcryperiodRevisionofexperimental designsBestknownnwvwigcoral.(Seedetailelaterincap.runs)Recoveryalernalees:IncreaseScc.skrilgeratioSloptecdingperiodicallyAlkalineadditionCombination-222lactorial designNote:*Discussion/agreement amongresearchersupervisnrandCo-supervisorhavebeenreachedpriortoanymodificationstobetakenCoSummary of research problems/remedial actions/scope and approach modifications (corttd) 149Phase/duration Research problems and c o n c e p e i a l d R e m e d i a l a c t i o n s a r i d m o d i f i c a t i o n so ft h e o r i g i n a lp r o p o s a lo ft h eresearch works’3 . E s p e f l r n e n t i p r o g r a m3 . 1 S y n t h e t I c a l u o g eT o oh i g hC O D N S S a n d T OS l e n dd o g f o o dw i t hw a t e r. 2h r l / t e I V e o v e r n i g h tw a r m@6 5 - 7 0d e g r e e0 . 1 . 5 h r s / n ,l h rS a u t e / d r a i np o r t i o no ft h es o l i d s o u tT o o l o wN / PM du r e a / N e J 1 P 0 43 . 2S y s t e ms e tu pL e a k i p H p r o b e i r . a o f . m o o v e l lD o u b l eO . . l n ga r o u n dt h e p r o b e s / m o r eb o l t sL e a k dMebn w i t h o a n I r r gI u i d / N 2g a s3 . 3A 1 l J n I t l Z a t l o nF w n . n t a z l o nm a d et h e b l e n d e lM o v et h e b l e n d e rt ot h eC o l d r o o m ( 4 4d e g r e eC )C l o g g i n gi n s i d ,t h et u b e o o n n . o d n gL e v e l i n gt i l ee f f l u e n t n ef r o mt h e b l e n d e r1 0t h ,b l e n d e re n d M . I A S Bi M U e rt h e A 4 I A S Ba i n i s h i r , o l a c ea l lp i e s l i dt u b . ,w i t ht h et h i o k a ro n e , u s e df o rf o o d / b e v a r a g WC o n n e d t h e s o f tt u b e sb e l w e e f lt h e h a r do n e s /aquee r e g u l r l yN o g a sp a s s i n gt h r o u g ht h e tg a s f l o wm e t e r sM a k e U 4 u b et i l le f f l u e n tl i n e o f b o t hr e a d t e r a /P l e c es e a l e r i tO u t s i d et h e0 - i l o gb e r w . e nc o v e ra r i d r e a d e r sS l u d g es p i l l a g eS l m p l 6 y / s t i o r t e n r e c u c et h e t u b i n gl i n e a r i da n d C o n f l e a e r v m p i a c ec o n . 4 h a p .c o n n e d e r sw a t tt h ee t r a t q n t o n e sa r i dp s t i d d , m p s w i t ht I l em e t a lo n e ,R u n n i n gc o n d l t l o n e :R e v i s er u n n i n gC o n d i t i o n s :3 5d e g r e eC / p H5 / 7S a m e a sp r o o o a e a .e x c e p t F R5 4F 1 0 , S R8 0 2 0 ,R A4 / 7( S p i l i a g e / t t r n eC e c y s )M b ca ’2 0r p m3 . 4E x p e r I m e n t a lr u n s3 . 4 . 1O p t . o p a r a t l n gC o n d .S a m ea st h o s e m e n t i o n e dI n2 . 0C o n s i d e n n go o n t m e n t S / t l r n eC o n s t r a i n t s ,R e v i s no r t h ew p r o a c nw a sa s :U s eS u r t a c er a s o o n s .m e t h o d( S R M ) I22 t a d o r , Lc e s i g ni n s t e a d o f2r2 f e d o r a l d e s i g nP s e u d o - e t e a c ys t a t e :2 - 3H R T 1 S - 1 0% v a r i a t i o no fa l lr e s p o n s e sPhase/durationR e s e a r c hp r o b l e m s and concepeial I d e a s R e m e d i a la c t i o n sa n dm o d i f i c a t i o n so ft h eo r i g i n a lp r o p o s a lo ft h eresearchw o r k s*P h a s eI:R e f e r e n c ec o h d t l o n( A c d l m n a l i i o n )R u n sS R P RF R0& 2 04 1 75 - 813 C . C2 . 1 45 42 2OS f 1 05 - 635 0 / 5 05 / 1 03 - 648 0 2 O2 1 45 - 6P h a s e2 :5 e s tI m o w nc o n d i t i o nR u n sS RP RF R08 0 ( 2 04 / 75 - 617 0 / 3 0 35 - 62X / 1 03 1 . 8$ 437 0 / 3 05 15 - 849 0 ( 1 03 / 85 - 8P h a s e3 :A d d i t I o n a lr u n eR u n sS RR PF RI8 0 / 4 03 / 85 - 628 0 / 4 0 3 / 85 - 638 0 / 2 05 / 85 - 6N o r.pIt.f o r . e U ’r u nt o celeie deateradion Cajtela e l f e c n f i n t a r a C t i o nb a s e do f lr . p & s t eo fS Ra n d R Rw t h tImaJrspIsa ’c e m e rp t . (ailristIon)C o m o a r e3 . 0 .a ’c e n t e rp t .w E l lth0a ’s a u lr u n n i n gc o n d i t i o nN o acnmnt ulnge i nt h ei r i s i o rr i e p o n s .p e r s s i r e r sC h e c i cM L / S Sa ’e a d ir u n n i n gc o n d i t i o no f e e u l r u n n e l g c o n d a f o n3 . 4 . 2U I X . I o a d i n g fS a m ea s tb,. m e n t i o n e d I n2 . 0U m e a t I o no f S l u d g ep r , p a r s t b n l l l t n eC o n s t r a l n t sR e c o v e r yp e r i o dA p p r o a u lw a st w e e da s :MaadaHRT.d 96 . 54 . 53 . 02 . 2 51 . 51 . 1 3R e C o v e r y , H R T - d2 . 2 53 . 04 . 59 . 0M G L H.a l l ’ L l n ee d d t l u f l7 7 7 7150Volum. of s..d sludg. r.quir.d for acid-phas. r.act.r:• 0.520Utr.— 10 Iltr. • 10 lltr. tap wat.rVolum. of s..d sludg. r.quir.d for m.than.—phas. r.aet.r:O.525 iltr.• 12.5 Itt. • 12.5 Iltr•tapwat.r.comm.nd.d start—up loading:1.2 gCOD/i/d 10.1 gCOO/gVSS/d @ 58-hr HRTI and/or5.0 KgCOD/cu.m-d to. 1-0.2 KgCOD/KgTS/dICh.ck loading rat.:It pri.sI: s.c.sI • 80 20Th.n, mix.d liquid aludg. conc.ntration:Clvi .C2V2 CVC[VSSI = tt0.8V17293H0.2*117721]/V• 16,189Mg/ISimilarly, CtTSJ • [tO.8333691•[0.2 199733.1/V=30,890 Mg/ICECODI - U0.8328721•t0.2254671]/V• 31391Mg/ISludg. loading rat. • ttCOO/VSSIFLOWJ/V• 0.I9COD/9VSS/d= ([3139 1/i6t891/451f1owTh.n, Flow 2.32 l/d OKVolum.tric loading rat.:• t[31391/[45*1000J]*flow• 1.2 gCOD/i/dTh.n, Flow • 1.72 l/d OK(a) (b)Constituents Synthetic Sludges (%) Constituents Analysis (%)Primary Secondary ‘No Name’ Special Dinner foe DogsDog Food 86.50 93.00 Proteins 22 (mm)Soap 3.00 0.25 Fat 7 (mlri)011 3.00 2.00 Carbohydrate 54 (mm)CaC 2.00 Fibre 5 (max)NaHO I’H 0 1.50 3.25 MoIsture 12 (max)Paper 2.00MgCp 2.00tires 1.501 5 1:.:Tae::A3;1:::D:etai!ed::Si( 1 ) . D e s i g n C r i t e r i a1 . 1 ) S y s t e mS u r f a c eL o a d i n gR a t e ( S y s - S L R )• 1 - 1 , 5m 3 / m 2 . h r1 . 2 ) S e t t l e r S u r f a c e L o a d i n g R a t eL e s s T h a n 0 . 7m 3 / m 2 . h r1 . 3 )G a s C o l l e c t i o nA p e r t u r e( G C A ) L e s sT h a n2 . 0 m 3 / m 2 . h r1 . 4 )5 0 oI n c l i n e d W a l l s1 . 5 ) D e s I g n e dH R T : 2 h r s .. 9d a y s1 . 6 )A c t I v e S l u d g eB l a n k e t / B e d( A S B ) a n d S e t t l e rR a t i o —7 : 31 . 7 ) P r o p e rB a f f l eA r r a n g e m e n tB e n e a t hG a sC o l l e c t o r( 2 ) . R e a c t o rV o l u m eS y a - S L R— 1 . 0 - 1 . 5 m 3 / m 2 . h r( 1 . 0m 3 1 m 2 . h r )D i a .o fr e q u i r e d a r e a— 1 2 . 5c m s .A r e ar e q u i r e d( 2 2 / 7 ) * d 2 1 4— 0 . 0 1 2 3m 2M a x . F l o w( 0 )• Ar’S L— 0 . 0 1 2 3m 2*1m 3 / m 2 . h r0 . 0 1 2 3 m 3 / h r w 2 9 5 l / dC r i t i c a l H R T— 2 h r s :R e a c t e rV o l .—H R T ’ Q2 h r s . ’ 0 . 0 1 2 3m 3 / h r s= 0 . 0 2 4 6m 3 2 5l i t r eM mF l o w( ( 0 , 0 2 4 6m 3 ) / ( 9d a y s ) )* ( 10 0 0L / m 3 )= 2 . 7 3L / d( 3 ) .R e a c t o rH e i g h t( R H )A p p r o x . ,R H— V o l / A r e a r e q ’ d—( 0 . 0 2 4 6m 3 ) / ( 0 . 0 1 2 3m 2 )—1 . 9 9 w 2 . O O mS e t t l e rV o l .— 0 . 3 2 5 . 0 0— 7 . 5l I t r e0 . 0 0 7 5m 3D o u b l i n gs e t t l e r sd i a m e t e r— 1 2 . 5 * 2— 2 5 . 0 0 c m .A r e a r e q ’ d— 0 . 0 4 9 1m 2S e t t l e rH— ( 0 . 0 0 7 5m 3 ) / ( 0 . 0 4 9 1m 2 )—1 5 . 2 7 c m 1 5 c mC o n n e c tV— 5l I t r eA S V • 2 5 - 7 . 5 - 5 . 0 • 1 2 . 5 D t r eA S H ( 0 . 0 1 2 5 m 3 ) / ( 0 , 0 1 2 3m 21 . 0 0 m( 4 ) . Q a sC o l l e c t i o n A p p a r a t u sG C A=2 . 0 0m 3 / m 2 . h rA r e aR e q d— F I o w / Q C A— ( 0 . 0 1 2 3m 3 / h r ) / ( 2 . 0 0m 3 / m 2 / h r )0 . 0 0 6 2m 2D i a . o fG C A—( ( 0 . 0 0 6 2m 2 ) * ( ( 4 ) / ( 2 2 1 7 ) ) 1 / 2=0 . 0 8 8 5m . w8 . 8 5c m( 5 ) . A d d I t i o n a lS e t t l e rA r r a n g e m e n tD o u b l i n gt h e s e t t l e r ’ sd I a m e t e r( 1 2 . 5c m . *2 w 2 5 c m )t os l o wd o w nt h el i q u i dv e l o c i t yp a s s i n gt h r o u g ht h ee f f l u e n tw e l r .C H E C K :S e t - S L Ra 0 . 7m 3 / m 2 . h rS e t t l e ra r e a— ( 2 2 / 7 ) ( d 2 1 4 )•( / 7 ) ’ ( ( 0 2 5 ) 2 / 4 ) )A c t u a lS L R• ( 0 . 0 0 6 4m 3 / h r ) / ( ( 2 2 / 7 ) ’ ( ( 0 2 5m ) 2 1 4 ) )— 0 . 2 5m 3 / m 2 . h rO KT o h e l ps e t t l es o l i d sb a c kt o t h e A S B ,ap r o p e rb a f f l ea r r a n g m e n tb e n e a t ht h eg a s c o l l e c t o ra n d5 0 0I n c l i n e dw a l l@t h e c o n n e c t i o nb e t w e e ns e t t l e ra n dA S BI n c l u d i n gt h eg a sc o l l e c t o rw e r ec r e a t e d ..A.3.2.cii.zirlgcf.1.—a.ri’i[1]DesignCriteriaI.!SystemSurfaceLoadingRate(Sys—SLR)=1.0—1.5m3!m2.hr1.2SettlerSurfaceLoadingRate(Set—SLR)<or=0.7m3/m2.hr1.3GasCollectionApparatus(GCA)<or=2.0m3/m2.hr1.450oInclinedWalls1.5DesignedHRT=2hrs—9days1.6ActiveSludgeBlanket/Bed(ASB)andSettlerRatio=7:31.7ProperBaffleArrangementBeneathGCA[2]ReactorVolume[RV][3]ReactorHeight [RID[41GasCollecttonApparatusDia.SLRAreaMax.Crit.React.Mm.ApprS.Set.AreaSet-.Conn.Act.Sl.Act.S1TotalGCAAreaGCACheckreq’flowHRTvol.flowvol.dia.req’Highvol.vol.HighRHreq’Dia.SLRcm.m3/ni2.hrm2L/dhrs.lit.L/dm3cmm2cmlitASV,m3ASH,mmm3!m2.hrm2cm0.7m3/m2h10.0010.00791892161.750.0047200.0314152.130.00891.131.3420.00397.070.2510.5010.00872082171.930.0052210.0347152.130.01001.151.3620.00437.420.2511.0010.00952282192.110.0057220.0380152.130.01121.181.3920.00487.780.2511.5010.01042492212.310.0062230.0416152.130.01241.191.4020.00528.130.2512.0010.01132722232.510.0068240.0453152.130.01371.211.4220.00578.490.2512.5010.01232952252.730.0074250.0491152.130.01511.231.4420.00618.840.2513.0010.01333192272.950.0080260.0531152.130.01651.241.4520.00669.190.2514.0010.01543702313.420.0092280.0616152.130.01941.261.4720.00779.900.25I-’TableA41Developmentof asmallscale(1—litre)SyntheticSludgePreparation.F23toNór.1O,1ExperimentalCharacteristics,%TSRunsPrimarySyntheticSludgeCOONSSTDSTDTSSTDSTDVSSTDSTDTPSTDSTDPROT.STDSTDTOCTKNSTDSTDGARBSTDSTD(1)3.001.21.63.82379264930.830.351.220.8320303.31.5415.001726(2)1.421.21.62.90379364930.790.351.220.82203029.63.31.5415.801726(av)2.211.21.63.36379364930.810.351.220.73203029.63.31.5415.401726SecondarySyntheticSludgeCODNSSTOCINSTOSTOTSSTOSTDVSSTO$70TKNSTO570TPSTOSTOROT.STOSTOGARBTOCSTDSTD(1)2.902.173.514.64.11292.259883.602.46.70.901.31.822.50324112.501744(2)2.432.178.03.514.62.41291.669883.732.46.71.081.31.823.30324126.6738.31744{3flh)2.352.1718.13.514.62.11289.759883.592.46.71.801.31.622.50324127.9065.01744(2)3.102.1714.73.514.61.71287.659883.902.46.71.501.31.624.70324119.8957.31744(3)3.752.1713.53.514.61.81288.059884.102.46.71.801.31.625.60324126.8455.51744(4)2.752.1714.83.514.82.01289.359883.702.46.71.401.31.623.30324120.3154.7174415)2.412.1715.93.514.62.41287.959883.782.46.71.501.31.623.65324127.1060.31744(6)3.102.1715.23.514.62.31289.559883.982.46.71.591.31.624.90324120.9060.81744(7)2.842.1715.13.514.62.41290.059884.002.46.71.651.31.625.00324132.1060.21744(812.362.1713.83.514.62.81290.759883.802.46.71.491.31.623.80324121.1052.71744(912.672.1715.83.514.63.31290.559883.892.46.71.421.31.624.36324124.6081.31744(1012.902.1718.63.514.83.01289.559883.662.46.71.431.31.622.89324122.2068.01744(11)2.612.1718.43.514.62.81290.059883.642.46.71.451.31.622.78324117.0067.01744(12)2.612.1719.63.514.63.21291.059883.752.46.71.331.31.623.41324120.8073.71744lay)2.792.1716.13.514.62.51289.559883.822.46.71.511.31.623.91324123.3861.41744(4)(i)4.532.46.71.711.31.6(2)4.722.46.71.431.31.6(3)7.962.46.71.391.31.6(4)10.552.46.71.061.3i.e(av)6.942.46.71.401.31.6Note:12CombinationOptionsofFeedsolids(%T)S,Settlingtime(ST),Warmingtime.(Wi)(1)=OCT23,1987(1)=5%WT.(51=6%TRWT.(9)=7%TWT.(2)=NOV2,1987(2)=5%WT.(6)=6%TRWT.(10)=7%TWT.(3) =NOVIO, 1987(3)=5%WT.(7)=6%TRWT.(11)=7%TWT.(4) =DEC15,1987(4)=5%WT.(8)=6%TRWT.(12)=7%TWT.STO=Typical normalrangesofactualprimarysludgecharacteristicsU’TableA42Development of aScale-Up(30-hire)SyntheticSludgePreparationBetweenNovember 1710December 30,1987PrimarySyntheticSludgeExperimentalCharacteristics,%TSRunsCODNSSTDSmTSSTDSTDVSSTDSmTKNSTDSTDTPSTDSTOPROTSWSTDCARBOSWSmTOC(1)2.271.21.62.33788.864933.11.540.980.31.219.2203035.7172642.72.461.21.62.13788.164933.11.540.940.31.219.5203028.6172634.42.511.21.61.93787.264933.11.540.940.31.219.5203027.2172627.9[avl2.411.21.62.13788.064933.11.540.950.31.219.4203030.5172635.02.301.21.62.13787.764932.91.540.930.31.217.5203021.5172635.62.211.21.62.33788.964932.81.540.890.31.217.7203017.7172629.6(2)2.291.21.62.33787.864932.91.540.830.31.218.1203017.8172649.21.941.21.62.93789.764933.11.540.810.31.219.3203017.7172628.3[avj2.191.21.62.43788.564932.91.540.870.31.218.2203018.7172635.71.541.21.63.03790.364933.51.540.920.31.221.8203023.1172631.51.691.21.62.63789.264933.61.540.890.31.222.3203022.0172632.2(3)1.301.21.62.43788.864933.61.540.940.31.222.3203013.5172652.01.831.21.62.23788.564933.51.540.910.31.222.1203023.1172649.8[avj1.591.21.62.53789.264933.61.540.920.31.222.1203020.4172641.41.581.21.63.23790.964933.91.541.050.31.225.520301.891.21.63.63791.064933.91.541.050.31.225.52030{4)2.091.21.63.33791.064933.91.541.080.31.225.420302.071.21.63.33790.864934.11.541.070.31.225.92030[avj1.911.21.63.43790.964933.91.541.060.31.225.62030•.:.•Note::(1)=NOV17,1987(2) =NOV25.1987(3)=DEC1,1987(4)=DEC30,1987.:.STD=Typicalnormalrangesofactualprimarysludgecharacteristics.V•C,’TabI&A42DeIópmeAt&a..Scálé—Up(3O-litre)SynthéticSiudgèPreparationBetweenNovember1710December30,1987(cont’d)SecondarySyntheticSludgeExp.Characteristics,%TSRunsCODNSSSTDTSSTDSTDVSSTDSTDTKNSTDSTDTPSTDSTDPROT.STDSTDCARBO.TOCSTDSTDCINSTDSTD{1)2.652.21.71.0287.459883.22.46.71.71.31.619.8324122.930.117449.43.514.62.502.21.71.0287.159883.02.46.71.61.31.618.4324130.332.5174411.03.514.63.072.21.91.0287.559883.12.46.71.51.31.619.0324132.047.6174415.63.514.62.382.21.81.0287.959883.12.46.71.51.31.619.0324125.942.8174414.03.514.6lay]2.652.21.81.0287.559883.12.46.71.61.31.619.1324127.838.3174412.53.514.62.322.22.31.0289.159883.72.46.71.51.31.623.0324119.845.4174412.43.514.61.922.22.41.0289.559883.72.46.71.41.31.622.3324118.032.417448.93.514.6(2)2.192.22.21.0289.459883.62.46.71.51.31.622.5324118.734.317449.53.514.62.262.22.21.0288.859883.42.46.71.41.31.622.2324124.136.5174410.73.514.6[avj2.172.22.31.0289.259883.62.46.71.41.31.622.5324120.237.2174410.43.514.62.032.22.11.0288.159885.62.46.71.31.31.635.1324130.434.017446.13.514.62.192.22.01.0288.259885.82.46.71.61.31.636.4324125.532.717445.63.514.6(3)2.202.21.91.0288.859886.42.46.71.81.31.640.0324125.034.117445.33.514.62.212.22.01.0288.559885.52.46.71.31.31.634.7324125.133.017446.03.514.6(av]2.162.22.01.0288.459885.82.46.71.51.31.636.6324126.533.417445.73.514.6Note{1}NOV25,1987{2}=DEC11987(3)=DEC231987STD=TypicalnormalrangesofactualprimarysludgecharacteristicsC,’C,’TabliA5.1SumniäMotoringonthePrimarySyntheticSludgesUsedThroUghOuttheExpérimentalPrógram:.:c::BetweenApril13,1988toDecember21,1989••:DateDaysCharacteristics,%TSCOD,mILVSSCOD!SThSTDTSSTDSTDVSSTDSTDTKNSTDSTDTPSTDSTDPROT.STDSTDTotalSol.mgILVSS04/13/881375057084245501.531.21.62.103.007.0089.1564933.851.54.000.910.351.2024.08203005/10/8828379594549243201.561.21.63.303.007.0091.9464933.521.54.000.800.351.2022.00203005/31/8849436625191254801.711.21.63.263.007.0092.6864934.061.54.000.870.351.2025.37203007/12/8891279075349204801.361.21.62.163.007.0087.7964933.851.54.000.860.351.2024.06203008/16/88126239525509168801.421.21.62.843.007.0088.8064933.241.54.000.990.351.2020.25203009/30/88171305157340248001.231.21.63.413.007.0089.2564933.571.54.000.920.351.2022.31203011/01/88203238106587179601.331.21.63.643.007.0089.1264933.591.54.000.650.351.2022.44203012/09/88241304005440212801.431.21.62.873.007.0088.9984933.521.54.000.920.351.2022.00203002/14/89308259844724235861.101.21.62.563.007.0087.6564934.061.54.001.090.351.2025.37203003/14/89336488985371259501.881.21.62.663.007.0086.8464933.951.54.000.930.351.2024.69203004/18189371394375956238501.651.21.63.553.007.0084.2564933.431.54.000.990.351.2021.44203005/30/89413226126706.172301.311.21.62.473.007.0087.2164933.261.54.000.800.351.2020.38203007/04/89448272194930150601.811.21.62.473.007.0089.7064934.231.54.001.130.351.2026.44203008/01/89476229635147218101.051.21.63.753.007.0089.9664933.901.54.000.900.351.2024.38203008/22/89497244924525209501.171.21.63.073.007.0088.1584934.231.54.000.970.351.2028.44203010/03/89539260185041150901.721.21.62.283.007.0086.2684935.421.54.000.990.351.2033.88203010/25/89561285456373230201.241.21.63.033.007.0087.0464933.521.54.000.990.351.2022.00203011/21/89588357855567187801.911.21.62.653.007.0089.1964933.651.54.000.910.351.2022.81203012/21/89618264235854178501.481.21.62.503.007.0086.0164933.681.54.000.890.351.2023.002030Average307415644209951.471.21.62.863.007.0088.4164933.821.54.000.920.351.2023.862030STDTypicalnormalrangesofactual primarysludgecharacteristicsC” a,TableA51SummaryofDataMonitoringonthePrimarySyntheticSludgesUsedThroughouttheExperimentalProgramBetweenApril13, 1988toDecember 21,1989DayDaysVFA, mgILTot.VFANH4-NP04-PHAcHPrIso-HBrHBrA-HVrIso-HVrHVrHHemgILHAc04/1318812311551353110105/10/88281813451439014705/31/8849238046453410007/12/88919958591122518308/16/88126459082911116509/30/8817134127110119584527311/01/8820332138984585192121091882411475120457520802/14/8930838171162821223703/14/893361610675211610304/18/89371331149798311920905/30/89413351205391293016407/04/894483812945107778221908/01/894762612348110575720008/22I894971113456324511310/03!89539156436672410710/25189561141226357481915311/21I89588716659562712312I21I8961810139455518102Average23118735911247254158163c,1TableA52SummaryofDataMonitoredontheSecondarySyntheticSludgesUsedThroughouttheExperimentalProgramf..:.:..BéieeApriI13,1988toDecebei211989.DateDaysCharacteristics,%TSCOD,mg!LVSSCOD!SThTSSTDSTDVSSTDSTDTKNSmSTDTPSTDSmPROTSTDSTDSol.NGINSThSTDTotalSol.mg!LVSS04/13/881475057084163002.912.172.171.002.0089.7459884.952.406.701.361.301.603132417859.0241505/10/8828416327008188002.212.172.231.002.0086.8459885.092.406.701.511.301.603232418018.7541505/31/8849265417123157801.682.172.381.002.0093.8659885.612.406.701.411.301.6035324154613.0541507/12/8891255816357110852.312.172.161.002.0087.7959884.952.406.701.321.301.603132416859.2841508/16/88126305157340150102.032.172.531.002.0089.3259884.802.406.700.891.301.6030324165811.1641509/30/88171280166190157801.782.172.541.002.0088.9859884.942.406.700.861.301.603132417568.1941511/01/88203272006080138701.962.172.551.002.0086.2559884.572.406.701.431.301.602932417647.9641512/09/88241296227008161601.832.172.481.002.0092.7459884.902.406.701.501.301.603132417419.4841502/14/89308367686970157602.332.172.231.002.0089.9959884.112.406.701.111.301.602632417579.2141503/14/89336256516092155601.652.172.231.002.0088.5459883.592.406.700.951.301.6022324150112.1641504/18/89371297797324141602.102.172.461.002.0081.8859884.502.406.701.231.301.6028324171610.2341505/30/89413382077407150602.542.171.851.002.0086.0559884.062.408.701.361.301.6025324173110.1341507/04/89448437386839224101.952.173.111.002.0087.4959886.742.406.701.541.301.604232416969.8341508/01/89476251855074136901.842.171.941.002.0086.5359886.002.406.701.361.301.603832416308.0541508/22/89497266396827158101.682.172.561.002.0088.6859884.262.406.700.971.301.602732418018.5241510/03/89539239676281115002.082.172.001.002.0087.3959885.472.406.701.211.301.603432418087.7741510/25/89561285126289147101.942.172.731.002.0089.0359885.182.406.700.831.301.6032324159810.5241511/21/89588282317318161601.752.172.561.002.0087.2059885.272.406.701.321.301.6033324165811.1241512/21/89618260167236160301.622.172.581.002.0088.7759885.122.406.701.121.301.603232417859.22415Average310166729154542.012.172.381.002.0088.2759884.952.406.701.231.31.63132417069.664155ThTypical normalranges ofactualprimarysludgecharacteristicsI-’ 01 00TableA52SummaryofMonitoringDataontheSecondarySyntheticSludgesUsedThroughoutV:...::c::.thi:Experimental ProgramBeenApril1,19881oDateDaysNH4-NP04-PHAcHPrIso-HBrA-HVriso-HVrHHeTot.VFAHBrHVrmgILHAc04/13/8812311555454312105110/88281813441653710705/31/8849238052417307112/8891995291019808/16/881264590106871281527309/30/8817134127180811025211/01/882033213814554819412/0918824114751345691219302114189308381711461033025003114/89336161064110911504/18/8937133114222205/30/894133512025143607/04/8944838129171208/01!8947626123161108/22/8949711134975010/03i8953915642332510I25/8956114122351154711/21!895887166473212/21/89618101394581100Average231187256452169106C,’CD1 6 0A P P E N D I XBA c c l i m a t i z a t i o nP r o c e s sT a b l eB 1 . 1:A v e r a g eS y s t e mE f f l u e n t Q u a l i t ya n d R e m o v a lE f f i c i e n c ya t P s e u d o S t e a d y -s t a t eU n d e r D i f f e r e n tA l t e r n a t i v e sD u r i n gt h e A c c l i m a t i z a t i o nT a b l e B 2 . 1 - B 2 . 8: R e s p o n s eD a t ao f t h e S a m p l i n gP o i n t N u m b e r e d1 t o8 U n d e rD i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n g t h eA c c l i m a t i z a t i o n .F i g u r eB 1 . 1:E f f l u e n tQ u a l i t i e so f t h e M - U A S B ( C O D , M L V S S ,P 04- P ,T K N I T ’ P ) U n d e rD i f f e r e n tR u n n i n gC o n d i t i o n sD u r i n gt h e A c c l i m a t i z a t i o nF i g u r e B 2 . 1: S y s t e m G a sP r o d u c t i o na n d L o a d i n gR a t e U n d e r D i f f e r e n tR u n n i n gC o n d i t i o nD u r i n g t h eA c c l i m a t i z a t i o nN o t e: A l l s a m p l i n g l o c a t i o n sa r e i l l u s t r a t e di n F i g u r e4 . 2A c c l i m a t i z a t i o nA l t e r n a t i v e s :( a ) S e e d i n gb o t h A - U A S Ba n d M - U A S Bw i t hs l u d g ef r o m t h e L i o n ’ s G a t ea n a e r o b i cs l u d g ed i g e s t e r a n d u s i n ga s t e p - l o a d i n ga p p r o a c h ;( b ) S e e d i n gb o t h A - U A S Ba n dM - U A S Bw i t h a c c l i m a t i z e ds y n t h e t i cs e e d s l u d g ea n du s i n ga c o n s t a n t - l o a d i n ga p p r o a c h ;( c )S e e d i n gt h eA - U A S Bw i t ha c c l i m a t i z e ds y n t h e t i cs e e ds l u d g e ,b u t t h eM - U A S Bw i t hs l u d g ef r o m t h eL i o n ’ sG a t e a n a e r o b i cs l u d g e d i g e s t e r ,u s i n gas t e p - l o a d i n ga p p r o a c h .C, w C,.-E i. 1.00(iCr)znnznX0c-)OCO0T1Cl)(Q00.(TI00.00.c,‘i—w.()()C)C)C)()5)———.G-cia.c.cLa_u.ôh00c000)JCl)U).—a’U)—V.)O‘000WU)))O00——C)V.V.—OU).a’c0OO0O4V.—V.V.0—0’0U)1’3U)0000—0Cl.000.V.0000Cl.QsV.500000V.00U)V.‘3U)00—U)0’I’)NV.0—a—os)—V.)U)0O——0’—J—OU)..V..000—J0—-JU)-.J‘0‘0.V.C)Osa’4—Osa’———2t’3‘OsU)U)0.0050a’0.Os—0003.—V.Os‘0.‘0‘0IsOCl.‘0SM-——J1-0U)0’s0—U)V10IsJO—OU)—4U)OOOIsOIsOO\0—OU.V.V.00-J—U).1-.)U)0000IsO0—.J—soV.—IsOU)01-.)—V.IsO-———U)-CDa’IsO1-0—Os1-0001-0—-.2‘0‘0—U)V.Os0000).4 w—cJ—_,GO .i cn llI• . .Q’0C,,>1(DOOOC)flOfl<OOflOOOOfl1flOOOCflflOi_.CCTh<CO1OOI.PPPCCCCCCCCCCCCC)CCQCCCIIIIO00000000000000000000000000000000000000000000-.()fl(fl<<<<nnnr)<<<OOOO<<<9BB0000c.Cciu00000°00CCn0000“‘c”iijiii‘0--•ow0-0.C0-0.0-0.0-.-0--SD_90-0-B0--0-U)U)Cl)aa00a@a‘U)Cl)1WO1WO1WCl)C)C)C)-‘0pp0pppp00000000——00Va‘0-1.31-31.3U-.-0000W-‘000————00000%————UI—00I-.)‘00%1-3-.3—SOUI001.31.3.V)I’)-.31.3t..)—.10’1-30’1.3f..)00-—00000000——J-0±0000000—00•ft-3031.31.31.3..30%00-.0%%O00013—U0000Qs-.‘00a.3Wi.3.l..31.3‘0U1-.)OsUI—01J‘00%00VI‘0‘013OsUI-0%1.)0—1.3——-—000000——1.31.31.31-.)()0)00000—-a-1-3000%UIIQ-.VU..50‘0—0‘0—1-.).1.31.30000—I..3SO—1-3I.)Vi001-301.3000%1..)——01-31.3.‘01.30l.A-0’.c.3V..-.31-.)—UIUI‘00—IIIIIIIIIIIIIIIIIIIIIIIIIIII1 6 3T a b l e B 1 . 1A v e r a g eS y s t e mE f f l u e n t Q u a l i t y a n dR e m o v a lE f f i c i e n c yA t P s e u d o S t e a d y - S t a t e U n d e rD i f f e r e n tA l t e r n a t i v e sD u r i n gt h eA c c l i m a t i z a t i o n ( c o n t ’ d )R u n n i n g c o n d i t i o n s [ a ][ b ] [ c ]R u n n i n g t i i n e , d a y s4 8 2 2 5 0S y e m e f f l u e n tS o l i d sT S ,m g / L— 4 9 0 3 5 3 2 7 3 2 6 2V S ,m g / L2 7 4 01 8 9 71 1 0 1T S S ,m g l L8 3 7 1 6 5 2 7 7T V S S ,m g / L5 2 7 1 0 51 4 1T S .%0 . 4 9 0 . 5 30 . 3 3V S ,%d r y s o l i d s 5 4 . 8 83 8 . 5 13 3 . 5 9T S S ,%0 . 0 9 0 . 0 20 . 0 3T V S S ,%d r y s o l i d s6 2 . 9 4 6 2 . 9 7 5 0 . 4 0C O D , _ m g / LT o t a l C O D1 6 9 29 7 5 8 2 0S o l . C O D7 5 8 8 6 16 4 8I n o r g a n i c s , _ m g / LN H 4 — N 2 9 02 7 1 3 8 6T K N3 0 3 2 9 64 2 3T P7 47 9 7 3P 0 4 — P1 4 2 39V F A ,m g / LH A c1 1 21 1 64 5H P r1 0 5 2 0 7 2 3 1I s o — H B r 001 4H B r00 0A - H V r 0 0 0H V r 00 0I s o — H V r 000H H e00 0T o t a lV F A ,m g / L a s H A c ( M - U A S B )1 9 72 8 4 2 3 5T o t a l V F A ,m g f L a s H A c ( A - U A S B )5 1 6 4 4 4 9 4 5 6 6 7S y e mr e m o v a le f f i c i e n c yC O D _ R e m o v a l , _ %T o t a l C O D 9 49 8 9 8S o l . C O D8 6 8 79 1T S S R e m o v a l ,%9 7 9 99 9T o t a lV F A R e m o v a l ,% ( M - U A S B9 69 4 9 6T PR e m o v a l ,%5 4 5 56 4P 0 4 - P R e m o v a l ,%8 9 8 4 9 5N o t e :[ a ] S e e d i n g b o t h A - U A S B a n d M - U A S Bw i t h s l u d g e f r o m t h e L i o n ’ s G a t ea n a e r o b i c s l u d g e d i g e s t e r a n d u s i n g as t e p — l o a d i n g a p p r o a c h[ b ] S e e d i n g b o t hA - U A S Ba n dM - U A S B w i t ha c c l i m a t i z e d s y n t h e t i c s e e d s l u d g eu s i n g a c o n s t a n t - l o a d i n g a p p r o a c ht c ]S e e d i n g A - U A S B w i t h a c c l i m a t i z e ds y n t h e t i c s e e d s l u d g e ,b u t M - I J A S Bw i t h s l u d g e f r o m t h e L i o n ’ s G a t e a n a e r o b i cs l u d g e d i g e s t e r ,u s i n gas t e p — l o a d i n g a p p r o a c h1 6 4T a b l eB 2 .IR e s p o n s eD a t ao f t h e S a m p l i n g P o i n t N u m b e r e dIU n d e r D i f f e r e n tA c c l i m a t i z a t i o nA l t e r n a t i v e sA c c l i m .D a t e D a y s S o l i d s ,m g / L S o l i d s . % o r % T SC O D . m g / LA l t e r .T S V S T S S T V S S[ % ][ % T S ][ % ][ % T S ] T o t a ls o l u b l e( 1 )0 3 / 2 8 / 8 81 3 0 6 6 0 2 7 1 7 0 2 9 6 4 0 2 7 0 3 0 3 . 0 68 8 . 6 22 . 9 69 1 . 1 9 5 6 1 6 1 5 5 3 40 4 / 0 4 / 8 88 5 2 3 0 0 4 7 2 4 05 2 6 1 04 8 4 6 05 . 2 39 0 . 3 3 5 . 2 6 9 2 . 1 1 6 2 4 0 0 5 7 2 00 4 / 0 8 / 8 81 22 8 4 7 0 2 5 4 8 02 4 0 9 0 2 2 3 6 0 2 . 8 58 9 . 5 0 2 . 4 1 9 2 . 8 2 7 8 9 2 06 0 7 40 4 / 1 2 / 8 81 6 3 5 6 2 0 3 1 9 2 0 1 8 4 5 0 1 7 1 2 0 3 . 5 6 8 9 . 5 91 . 8 59 2 . 8 03 3 3 3 6 6 0 0 00 4 / 1 5 / 8 81 9 3 2 4 8 0 2 8 9 3 02 1 2 2 01 9 6 9 0 3 . 2 5 8 9 . 0 72 . 1 29 2 . 7 95 0 7 4 25 2 4 50 4 / 1 9 / 8 82 34 5 3 9 0 4 0 9 3 02 7 6 3 0 2 5 5 6 04 . 5 4 9 0 . 1 72 . 7 69 2 . 5 1 5 1 5 2 45 6 3 90 4 / 2 3 / 8 82 73 1 3 2 0 2 8 5 4 0 2 2 2 9 0 2 2 5 3 0 3 . 1 3 9 1 . 1 22 . 2 3 9 2 . 1 0 9 6 6 0 45 0 8 40 4 / 2 6 / 8 83 0 4 9 9 6 0 4 5 1 6 0 3 2 7 4 0 3 0 1 7 0 4 . 9 9 9 0 . 3 93 . 2 7 9 2 . 1 55 9 5 1 45 3 0 40 4 / 3 0 / 8 83 44 7 6 0 0 4 2 6 1 03 0 4 2 0 2 8 1 9 0 4 . 7 68 9 . 5 2‘ 3 . 0 49 2 . 6 7 3 5 4 8 25 9 6 70 5 / 0 3 / 8 8 3 7 4 2 2 0 03 7 8 3 0 2 8 9 8 0 2 7 1 8 0 4 . 2 2 8 9 . 6 42 . 8 9 9 3 . 7 9 2 4 9 9 85 0 0 00 5 / 0 7 / 8 8 4 13 3 2 5 0 2 9 9 4 0 2 0 1 9 0 1 9 1 5 0 3 . 3 2 9 0 . 0 02 . 0 29 4 . 8 53 0 2 0 4 4 9 8 00 5 / 1 0 / 8 84 42 6 3 0 0 2 3 2 2 0 3 5 4 1 0 3 2 5 4 0 2 . 6 3 8 8 . 2 93 . 5 49 1 . 8 9 3 3 1 9 7 5 6 9 70 5 / 1 4 / 8 84 8 3 1 0 7 0 2 7 6 8 0 2 4 7 3 02 2 9 3 0 3 . 1 18 9 . 0 9 2 . 4 7 9 2 . 7 2 2 4 7 4 7 5 4 7 70 5 / 1 7 / 8 85 14 5 5 0 0 4 0 7 9 02 9 7 1 0 2 7 7 7 04 . 5 5 8 9 . 6 5 2 . 9 7 9 3 . 4 7 3 2 1 9 35 3 1 2( 2 ) 0 5 / 3 1 / 8 81 3 3 4 5 0 3 0 6 6 02 2 5 2 02 2 0 2 0 3 . 3 5 9 1 . 6 6 2 . 2 59 7 . 7 83 2 7 2 7 7 9 6 00 6 / 0 7 / 8 884 0 9 4 03 6 7 1 0 3 3 6 5 0 3 1 1 1 0 4 . 0 98 9 . 6 73 . 3 69 2 . 4 25 5 9 3 6 7 2 0 30 6 / 1 4 / 8 81 5 4 0 1 0 0 3 7 1 4 0 3 4 1 2 0 3 3 3 8 0 4 . 0 1 9 2 . 6 23 . 4 19 7 . 8 34 5 5 4 58 1 9 80 6 / 2 1 / 8 82 2 4 1 9 0 0 3 8 7 0 0 3 3 1 9 0 3 1 5 3 1 4 . 1 9 9 2 . 3 6 3 . 3 2 9 5 . 0 0 4 9 6 0 0 5 7 6 00 6 / 2 8 / 8 82 9 3 3 5 1 0 3 0 6 8 0 2 5 2 4 0 2 4 2 2 5 3 . 3 5 9 1 . 5 5 2 . 5 2 9 5 . 9 8 2 9 2 6 8 5 2 8 5( 3 ) 1 1 / 1 5 / 8 81 2 6 4 1 5 2 2 4 6 5 2 2 0 3 0 1 9 5 2 02 . 6 48 5 . 0 5 2 . 2 0 8 8 . 6 1 2 9 2 4 95 1 3 81 1 / 1 8 / 8 8 42 9 2 5 0 2 5 4 6 5 2 8 1 5 0 2 5 1 1 0 2 . 9 38 7 . 0 62 . 8 2 8 9 . 2 0 4 4 4 4 45 0 7 91 1 / 2 2 / 8 88 2 3 7 2 0 2 0 4 6 0 2 1 3 4 0 1 9 6 6 0 2 . 3 7 8 6 . 2 62 . 1 39 2 . 1 35 4 4 7 5 5 6 8 11 1 / 2 5 / 8 81 1 2 9 1 8 0 2 5 5 8 0 2 8 9 7 02 6 4 0 02 . 9 28 7 . 6 62 . 9 0 9 1 . 1 3 3 2 2 5 8 5 4 0 31 1 / 2 9 / 8 81 5 3 2 1 8 0 2 9 1 9 0 2 5 3 6 02 4 3 8 03 . 2 29 0 . 7 1 2 . 5 49 6 . 1 4 3 2 8 0 06 0 0 01 2 / 0 2 / 8 81 8 2 9 1 6 0 2 6 3 6 0 2 9 6 9 0 2 8 2 4 0 2 . 9 29 0 . 4 02 . 9 79 5 . 1 23 3 1 9 8 5 3 4 41 2 / 0 6 / 8 82 2 3 6 8 6 5 3 3 4 7 0 3 5 6 6 0 3 4 0 2 0 3 . 6 9 9 0 . 7 9 3 . 5 79 5 . 4 02 6 7 2 1 5 1 8 21 2 / 0 9 / 8 82 53 7 6 6 53 4 5 9 5 3 2 6 5 03 1 2 4 0 3 . 7 79 1 . 8 53 . 2 79 5 . 6 84 5 6 6 96 5 3 51 2 / 1 3 / 8 82 9 3 5 8 0 03 2 6 8 03 4 0 4 03 2 9 0 0 3 . 5 89 1 . 2 8 3 . 4 0 9 6 . 6 5 3 0 7 0 9 5 1 9 61 2 / 1 6 / 8 83 2 3 2 0 4 5 2 8 7 6 0 2 4 1 3 02 2 9 2 0 3 . 2 08 9 . 7 5 2 . 4 1 9 4 . 9 9 3 3 0 0 6 7 0 7 31 2 / 2 0 / 8 83 6 2 9 3 4 02 6 2 5 5 2 2 1 8 02 1 0 9 02 . 9 38 9 . 4 9 2 . 2 2 9 5 . 0 9 3 6 2 9 2 5 9 9 61 2 / 2 3 / 8 83 9 3 3 3 3 5 3 0 3 7 0 2 8 9 7 0 2 7 5 8 0 3 . 3 3 9 1 . 1 ! 2 . 9 0 9 5 . 2 0 3 3 7 3 56 3 4 51 2 / 2 7 / 8 84 33 5 2 6 0 3 2 0 0 5 3 0 8 3 02 9 3 4 03 . 5 39 0 . 7 7 3 . 0 8 9 5 : 1 7 5 0 4 0 0 6 8 8 01 2 / 3 0 / 8 84 63 8 0 2 03 4 8 1 0 2 5 4 8 0 2 4 4 5 0 3 . 8 0 9 1 . 5 6 2 . 5 5 9 5 . 9 6 3 6 5 0 8 7 6 1 90 1 / 0 3 / 8 95 0 3 2 5 1 5 2 9 6 1 0 2 6 7 1 0 2 5 1 9 0 3 . 2 59 1 . 0 7 2 . 6 7 9 4 . 3 1 4 0 3 9 6 6 9 7 00 1 / 0 6 / 8 95 3 2 5 5 8 02 2 8 4 0 2 8 8 5 0 2 7 2 1 02 . 5 68 9 . 2 9 2 . 8 9 9 4 . 3 2 2 8 6 8 5 5 9 7 6( 4 ) 3 4 2 9 0 3 0 5 6 3 2 9 9 5 0 2 7 7 4 7 3 . 4 3 8 9 . 0 1 2 . 9 9 9 2 . 6 9 3 0 0 4 6 5 4 9 5( 5 )3 8 5 0 3 3 5 5 0 7 3 0 8 5 02 9 7 1 23 . 8 59 2 . 1 8 3 . 0 8 9 6 . 2 7 4 1 4 7 1 6 4 1 4( 6 ) 3 2 0 3 8 2 9 0 8 7 2 7 0 1 3 2 5 6 1 73 . 2 09 0 . 6 4 2 . 7 0 9 4 . 8 6 3 5 1 9 6 6 8 5 5TableB2.1ResponseDataof theSamplingPoint NumberedIUnderDifferent AcclimatizationAlternatives(cont’d)Acci.DateDayInorganics, mgILVFA,mg/LTot.VFAAlter.NH4-NTKNTICN. XiSTP, %TSTI’P04-PHAcHPrIso-HBrHBrA-HVrlio-HVrHVrHHcmg/I..HAc(1)03/28/88I26.401473.781002.001305203855104/04/88837.502501.521701.8099401263944904/08/881245.863862.071481.761274253110122465104/12)881630.564501.591422.0319632442116184545(‘4115/881928.761663.661520.90124127335218904/19/882328.761963.931581.1812822811315742704/231882729.872973.252060.751212821631237354104/26/883040.642423.151520.96133535404218390124104/30/883437.772494.161830.9113544029317232598605/03/883718.073183.651591.0612430719311624368605/07/884123.002393.691570.9711935727113227282705/10/884423.002663.581661.1312231724812525075005/14/884821.002573.011420.821222362111002543064205/17/885128.002433.001700.741424794771243521157(2)05/31188I86.003264.862781.8926870760777297142606/07/88844.003124.051841.0216784213736242111706/14/881529.002624.551900.8815797913369462139906/21/882224.003044.141680.811365464924072706/28/882922.002804.271690.81124556136119251895(3)11/15/88113.152633.431811.6414175370211698145911/18/88428.342863.411372.02106463377627085211/22/88874.003294.942011.7014989079615854167511/25/88ii72.003395.072011.751621198111219927225111/29/881595.004224.852051.8614997584014830177512)02/881843.003424.071531.351325824244595212/06/882230.003504.351591.36143504640157-113012)091882526.003433.952330.931787551077273l81412/13/88299003024.131740.92141559893153138712/16/883218.003624.201721.05118508788ItS122512)20/883618.003454.181541.22130376498631483112/23/883957.223384.041920.961415496644223949128512)27/894357.223044.501720.971608691419106238223212)30/884672.604194.612161.0317188214151620090221101/03/895018.003454.141871.0216010281620106204253401/06/895330.003945.102131.072207881295591821985(4)24.002553.201590.90129344312116250254191850(5)25.002824.321760.83139694106119692464621007(6)40.203864.622051.041848991443602001592243No1e:(4),(5),aod(6)areaveragere.ponaeaatpacudoateady-ate(6-14to6-28,1988;5—10to5-17,1988;12-30to01-06,1989)foralter.I.2,ad3respcctivclyv1166Table B2.2 Response Data of Sampling Point No.2 Under Different Acclimatization AlternativesAcdlim. Date Days Solids, mgfL , mg/L Inorganics. mgfLAlter. TSS TVSS [%] %TSJ Total Sol. NH4-N TKN TKN 1? TP P04—P[%TSJ [%TSj(1) 03/28/88 1 46670 43880 4.67 94.02 100606 11071 277 398 1.19 190 2.76 20204/04/88 8 37640 35320 3.76 93.84 77600 9920 288 150 3.32 110 2.32 18404/08/88 12 41400 38910 4.14 93.98 88012 9380 250 545 1.74 162 0.87 18304/12/88 16 40700 38650 4.07 94.96 69172 10834 270 446 1.71 154 0.91 20204/15/88 19 41250 38560 4.12 93.48 78884 10362 242 242 5.97 172 0.67 20904/19/88 23 41470 39210 4.15 93.94 67792 10169 235 212 5.45 168 0.63 18704/23/88 27 46690 43990 4.67 94.22 76677 10345 275 282 5.97 183 0.57 20504/2H88 30 58540 55170 5.85 94.24 113776 9676 216 275 5.52 183 0.58 17904!30,’88 34 54530 51700 5.45 94.81 116122 10161 276 348 5.75 193 0.82 18605/03/88 37 54150 51360 5.42 94.85 105638 9193 259 366 6.07 183 0.93 18305/07/88 41 52500 49790 5.25 94.84 89795 9388 304 336 6.21 191 0.59 19005/10/88 44 50660 47960 5.07 94.67 108608 10451 280 363 5.84 213 0.55 18305/14/88 48 50990 48440 5.10 94.99 95335 10832 253 339 5.89 207 0.60 19305/17/88 51 50990 48600 5.10 95.31 120724 9416 245 329 5.81 192 0.60 195(2) 05/31/88 I 45330 42990 4.53 94.84 89293 8768 455 368 6.82 202 0.82 19506/07/88 8 55030 51280 5.50 93.19 80080 9537 327 396 6.15 214 0.85 20706/14/88 15 51280 48810 5.13 95.18 105743 8673 292 350 6.12 182 1.05 17806/21/88 22 53790 50132 5.38 93.20 111200 8800 224 268 6.24 174 0.81 17106/28/88 29 53600 51390 5.36 95.88 127525 7480 89 108 7.54 195 0.94 71(3) 11/15/88 1 56560 54130 5.66 95.70 74310 10751 299 368 6.57 204 0.84 20311/18/88 4 60880 57990 6.09 95.25 98413 9762 266 353 5.89 192 0.81 18211/22/88 8 50100 48160 5.01 96.13 71595 10350 297 388 7.45 195 0.66 19011/25/88 11 55730 53500 5.57 96.00 108065 10484 284 470 8.11 234 068 20011/29/88 15 52950 50510 5.30 95.39 105600 9600 293 417 7.85 199 0.76 18212/02/88 18 40190 38300 4.02 95.30 85020 8907 287 342 6.50 173 0.82 16612/06/88 22 59840 57370 5.98 95.87 86640 9474 230 278 6.27 165 0.81 16612/09/88 25 50720 48480 5.07 95.58 96063 10315 193 302 6.08 201 0.81 17812/13/88 29 38590 36600 3.86 94.84 63780 8268 133 224 5.07 144 0.67 14112/16/88 32 51420 49260 5.14 95.80 117092 10295 216 299 5.8 205 0.69 18712/20/88 36 49930 48050 4.99 96.23 107298 11124 260 354 5.95 205 0.74 18312/23/88 39 48640 46730 4.86 96.07 62651 10683 268 330 5.62 198 0.68 19012/27/88 43 64220 61890 6.42 96.37 80800 11120 287 356 6.21 192 0.78 19012/30/88 46 45960 44110 4.60 95.97 84921 10159 319 428 5.64 199 0.81 17901/03/89 50 49020 46930 4.90 95.74 90297 10455 287 336 5.98 176 0.98 18301/06/89 53 42990 41230 4.30 95.91 64542 9721 293 394 5.84 191 0.72 182(4) 50880 48333 5.09 94.99 108222 10233 259 344 5.85 204 0.58 190(5) 52890 50111 5.29 94.75 114823 8318 202 242 6.63 184 0.93 140(6) 45990 44090 4.60 95.87 79920 10l12 300 386 5.82 189 0.84 181167Table 82.2 Response Data of Sampling Point No.2 Under Different Acclimatization AlternativesAcci. Date Days VFA, mg/L Tot.VFAAlter. HAc HPr iso- HBr A-HVr Iso— HVr HHe mg/L HAcHBr HVr(1) 03/28/88 1 2506 1765 40 1490 498004/04/88 8 2246 1740 36 1521 782 517804/08/88 12 1544 1185 25 1173 582 366404/12/88 16 1810 1587 31 1426 724 451604/15/88 19 1459 1471 24 1226 601 385804/19/88 23 1511 1606 28 1276 661 409104/23/88 27 2128 2364 37 1204 18 39 694 88 537804/26/88 30 2080 2498 31 1131 16 35 632 3 530104/30/88 34 1751 2034 42 1189 26 52 696 4 469705/03/88 37 1648 1824 32 1154 18 38 622 4 433605/07/88 41 1663 1998 43 1220 26 55 698 4 460405/10/88 44 1710 1793 36 1173 20 44 665 4 441805/14/88 48 1982 2089 40 1316 23 52 792 5 511305/17/88 51 1754 1798 36 1266 22 47 749 5 4583(2) 05/31/88 1 1382 1565 49 929 31 66 747 106 386906/07/88 8 1313 1742 49 1043 30 61 947 695 444006/14/88 15 1049 1601 49 1051 29 56 860 212 376306/21/88 22 1682 1690 27 990 17 37 765 153 430706/28/88 29 802 794 380 18 279 48 1904(3) 11/15/88 1 2125 2182 45 1027 19 59 590 110 507511/18/88 4 2065 2023 41 987 18 55 574 99 483811/22/88 8 2058 1853 49 1022 24 57 647 95 476811/25/88 11 2204 1958 47 1015 20 54 587 490411/29/88 15 2261 2060 53 864 22 58 546 82 496712/02/88 18 2142 2058 52 879 24 58 580 92 488212/06/88 22 2334 2025 27 1011 503 498012/09188 25 2395 2070 962 481 501212/13/88 29 1825 1724 756 432 399212/16/88 32 2321 2304 931 506 512212/20/88 36 2420 2468 26 1080 69 135 845 84 583612/23/88 39 2281 2295 30 1032 59 129 776 80 547412/27/88 43 2643 2547 31 1107 49 770 96 601512/30/88 46 2321 2236 36 938 99 730 82 532801/03/89 50 2535 2664 34 871 94 702 69 581601/06/89 53 2201 2431 34 854 18 100 663 69 5273(4) 1815 1893 37 1252 22 48 735 4 4705(5) 1178 1362 38 807 23 37 635 138 3325(6) 2352 2444 35 888 18 98 698 73 5472Note:(4),(5),and (6) are average responses at pseudo steady—state (6—14 to 6—28, 1988; 5—10 to 5—17, 1912—30 to 01—06, 1989) for alternatives 1, 2, and 3 respectively.Table82.3ResponseDataofSamplingPoint No.3UnderDifferent AcclimatizationAtternaLiiesAcclim.DateDaysSolids,mg/LSolids,%or%TSCOD,mg/IIriorganics, mg/IAlter.TSVSTSSTVSSTot.sol.NH4—NTKNThNTPTPP04-Pf%Jf%TSJ[%JI%TSI1%TSJI%TSJ(1)03/28/88173204870224020300.7366.530.2290.831515297582494305.782001.8618704/04/88866104500180015900.6668.080.1888.3314720129752831654.521602.0717704108188127330515028002554)0.7370.260.2891.071681198752574246.171422.0918804112/881664204500231020700.6470.090.2389.6116835104182324365.651602.0820004115/881978605670272025800.7972.140.2794.8523823107882402365.151803.1020704/19/882376905410292025500.7770.350.2987.3317965102542232324.671662.4520304/23/882783605980308027400.8471.530.3188.961712192912352864.961652.0218504/26/8830105208090748066901.0578.900.7589.4432254100002132645,081831.2917904/30/883499607350461041800.9973.800.4690.6739254106442302825.141941.8219305/03/8837100007410419038801.0074.100.4292.892177399992353485.001931.9419005/071884182805930303028400.8272.500.3093.731251796332553084.891972.4418805/10/884487306290368032900.8772.050.3789.401926297132452924.721852.2516905/14/884894806890418038000.9572.680.4290.9018797117242433294.702072.3619005/17/885199307430499045100.9974.820.5090.382253595772413084.971972.13197(2)05/31/88184406980469046100.8482.460.4796.1615111747542817406/07/88882705440413031000.8365.780.4175.0615855696238619806/14/881566404980206019600.6675.000.2190.301338692283423884.492043.1719906/21/88221289310627650059931.2882.420.6592.202464088802643085.691921.4617808/281882993306875397037200.9373.690.4093.701918790242342495.031692.48178(3)11/15/881216001807015405144852.1683.661.5494.0332411107513273684.612041.6320511/181884631305823559850567508.3192.255.9795.14109524107943253656.212060.7520011/221888357703225031800302103.5890.163.1895.005758887943304317.182140.7120311/25/8811489304469040000384404.8991.334.0098.1073387108453213978.422051.1520211/29/8815423803842046580442904.2490.864.6895.089200099203124317.562120.9819012/02/8818407003719040710389404.0791.384.0795.658178196363043466.161850.8217912/08/8822405103640028410271104.0589.852.8495.425508193932523506.532070.8916812/09/8825375703401034640329503.7690.523.4695.127718596062333106.801930.8117812113/8829393903553036410342003.9490.203.6493.938346595282152775.831820.6918412118/8832410103693030480290704.1090.053.0595.4458939104522452915.961910.691851212018836395803600034720334403.9690.963.4796.3159172112032853246.211910.761901212318839457204215033700324004.5792.193.3796.1481847131732803386.112000.7818612/27/8843425303879038060366104.2591.213.8196.1965600108003193826.212020.7618612/30/8846390403484034690332903.90‘89.243.4795.9663492107943313916.361990.9719001/03/8950351703183038120365703.5290.503.8195.9366535102182993915.082040.8318301/06/8953410303737041690398904.1091.084.1795.6837450109963304796.292470.90205(4)93806870428338670.9473.180.4390.2320198103382433104.801962.25185(5)96217494417738910.9677.040.4292.071907190442803155.071882.37184(6)384133468038167365833.8490.273.8295.8655828106693204205.912170.90193I-’ 0) 90Table 82.3 Response Data of the Sampling Po4nt Numbered 3 Under DifferentAcclimatization Alternatives (cont’d)Acci. Date Days VFA. mg/L Tot VFAAlter. HAc HPr leo-HBr H& A.-HVr o-HVr HVr HHe mg/I.. HAcNote:(4).(5),and (6) are average responses at pseudo steady-state (6—14 to 6—28, 1988: 5—10 to 5—17. 1988:12—30 to 01—06, 1989) for alternatives 1, 2, and 3 respectively.169(1) 03/28/88 1 1668 1179 29 938 328204104188 8 2090 1644 34 1429 74 446404/08/88 12 1349 1017 22 1053 512 320804/12/88 16 1286 1155 20 1124 547 332404/15/88 19 1540 1579 23 1334 669 413904)19/88 23 1571 1634 24 1333 674 421804123/88 27 1920 2169 28 1090 11 26 825 93 487804/26/88 30 1799 2157 28 953 11 30 533 75 459204/30/88 34 1956 2384 30 1212 15 42 629 3 512505/03188 37 1822 2079 30 1190 18 42 630 3 474605/07188 41 1959 2118 35 1360 20 51 739 4 510405/10/88 44 1766 1824 33 1207 18 48 664 4 452205/14/88 48 2110 2243 39 1459 22 55 850 5 549805/17/88 51 1963 2037 36 1340 21 54 782 5 5060(2) 05/31/88 1 1459 1410 40 855 25 55 677 93 370606/07/88 8 1074 1300 38 746 23 45 841 14 308706/14/88 15 1040 1800 54 1162 33 84 985 247 409306121/88 22 1430 1775 35 1030 21 46 854 176 422806/28/88 29 1887 2043 27 1016 17 40 771 144 4816(3) 11/15/88 1 2130 2345 52 1087 66 639 128 528811/18/88 4 2183 2213 49 1056 18 65 621 113 520311/22/88 8 2424 2365 54 1238 26 73 690 121 574811/25/88 11 2454 2285 81 1172 30 73 711 107 568211/29)88 15 2378 2104 57 1000 27 67 817 101 527312/02/88 18 2269 2006 48 889 22 55 545 490012106/88 22 2309 2121 941 505 496712/09/88 25 2256 2091 884 474 483312/13/88 29 2290 2281 897 516 505512116/88 32 2496 2520 34 954 558 554012/20/88 36 2349 2445 30 1004 89 140 816 70 567612/23/88 39 2229 2248 22 991 56 131 784 530212/27/88 43 2335 2311 30 966 61 133 744 83 548312/30/88 46 2414 2336 36 988 101 769 89 556401/03189 50 2305 2429 32 774 95 636 64 528701/06/89 53 2480 2767 39 951 21 109 726 70 5938(4) 1946 2035 36 1335 20 52 765 5 5026(5) 1452 1873 39 1089 24 50 870 189 4379(6) 2400 2511 36 904 21 102 710 74 5596170Table B2.4 Response Data of Sampling Point Numbered 4 Under Different Acclimatization AlternativesAcclim. Date Days ScUds, mg/I COD. mg/I lnorgamcs, mg/IAlter. TSS TVSS [%) [%TSJ Total Soluble Nl-14-N TKN TP P04-P(1) 03/28/88 1 1200 1050 0.12 87.50 11353 8848 273 379 160 20004/04/88 8 860 740 0.09 86.05 11040 9040 298 280 70 19304/08/88 12 1120 980 0.11 87.50 11940 793 265 440 144 19704/12/88 16 980 840 0.09 85.57 12834 10928 247 454 126 20904/15/88 19 970 890 0.09 91.75 12238 10020 220 240 162 20004/19/88 23 900 810 0.09 90.00 12287 9999 230 220 156 19904/23/88 27 1310 1040 0.13 79.39 11968 9615. 243 340 206 20104/26/88 30 1020 820 0.10 80.39 12591 9838 245 304 208 20304/30/88 34 1240 1090 0.12 87.90 13064 11209 250 318 207 20505/03/88 37 1330 1240 0.13 93.23 12902 10322 239 378 189 19005/07/88 41 1050 910 0.11 86.67 12653 8735 250 299 194 19005/10/88 44 950 750 0.10 78.95 12664 9959 267 306 188 17805/14/88 48 1400 1340 0.14 95.71 13753 9939 248 315 201 18605/17/88 51 1340 1130 0.13 84.33 13119 9829 243 305 196 187(2) 05/31/88 1 3260 3150 0.33 96.67 12000 6101 370 428 146 14106/07188 8 1880 940 0.19 50.00 10825 8410 407 415 202 19806/14/88 15 600 550 0.06 55.00 10891 8356 329 412 212 19206/21/88 22 630 505 0.06 80.20 9920 7840 257 284 274 17806/28/88 29 815 705 0.08 86.50 10650 8943 247 295 195 192(3) 11/15/88 1 1100 875 0.11 79.55 12095 10672 345 421 202 20311/18/88 4 1103 883 0.11 80.05 11587 10714 325 380 208 20011/22188 8 1024 966 0.10 94.34 12840 10895 322 417 203 20511/25/88 11 970 940 0.10 96.91 12661 10968 321 422 232 21311/29/88 15 894 846 0.09 94.63 11680 10080 345 489 236 19212/02/88 18 955 893 0.10 93.51 11012 9555 317 354 185 18612/06/88 22 938 888 0.09 94.67 10850 9069 265 290 157 17312/09/88 25 1283 1190 0.13 92.75 11575 8898 240 302 178 16412/13/88 29 1218 1138 0.12 93.43 11181 8583 210 236 152 16012/16/88 32 1150 1066 0.12 92.70 11081 9823 231 287 185 17812/20/88 36 1903 1803 0.19 94.75 13728 10729 299 358 207 19012/23/88 39 2300 2183 0.23 94.91 13655 10120 293 343 200 19012/27/88 43 1878 1768 0.19 94.14 13040 10000 312 334 191 19012/30/88 46 1463 1388 0.15 94.87 11984 8730 344 428 206 18301/03/89 50 1393 1285 0.14 92.25 10931 9227 402 350 196 18301/06/89 53 1403 1300 0.14 92.66 12510 10518 320 444 213 194(4) 1230 1073 0.12 86.33 13179 9909 253 309 195 184(5) 682 587 0.07 73.90 10487 8380 278 330 227 187(6) 1420 1324 0.14 93.26 11808 9492 355 407 205 187171Table B4 Response Data of the Sampling Point Numbered 4 Under DIfferent Acclimatization AlternativesAcclim. Date Days VFA. mg/I.. Tot VFAAlter. HAc HPr lso-HBr HBr A-HVr lso-HVr HVr HHe mg/I. HAc(1) 03/28/88 1 767 327 22 189 117604104188 8 1859 1456 31 1265 660 431104/08/88 12 2149 1667 37 1624 840 512704/12188 16 1607 1450 28 1381 690 414904/15/88 19 1411 1434 21 1229 601 378004/19/88 23 1649 1785 28 1420 724 450904/23/88 27 1905 2162 29 1131 12 28 610 3 483204/26/88 30 2044 2453 30 1069 14 32 582 3 515304/30/88 34 1999 2444 32 1230 17 42 651 3 526005/03/88 37 1676 2005 30 1154 16 36 624 3 450905/07/88 41 1596 1973 34 1213 19 42 697 4 449305/10/88 44 1717 1912 35 1241 20 44 708 4 459305/14/88 48 1795 2199 40 1391 23 51 845 5 509705/17/88 51 1620 1887 34 1196 12 48 723 5 4452(2) 05/31/88 1 1035 1118 38 628 25 51 500 266 287206107/88 8 1049 1536 49 871 30 59 768 188 352306/14/88 15 818 1721 56 1014 34 66 959 264 370206/21/88 22 1107 1654 37 818 22 45 816 184 364606/28/88 29 1681 2179 31 1011 18 43 845 162 4775(3) 11/15/88 1 1938 2247 53 952 24 77 550 110 488511/18/88 4 2095 2243 49 1040 23 69 590 111 511511/22)88 8 1985 2102 57 1080 29 68 689 95 497611/25/88 11 2339 2358 64 1226 31 74 760 108 569511/29/88 15 1976 2011 57 970 28 65 638 102 479012/02)88 18 2040 1719 41 853 18 45 501 437512106/88 22 1993 2139 31 891 554 468212109/88 25 1961 2047 30 835 507 450912/13/88 29 1730 2003 695 454 409512116/88 32 2223 875 561 326212120/88 36 2221 2614 37 971 74 140 830 89 568812123/88 39 1980 2361 33 926 59 129 780 77• 515712/27/88 43 2010 2433 37 873 71 758 85 513512/30/88 46 2120 2448 39 905 104 786 92 532001/03/89 50 1958 2447 39 706 98 646 83 493101/06/89 53 2100 2721 40 814 23 110 693 71 5411(4) 1711 1999 37 1276 18 48 759 4 4714(5) 1202 1851 41 948 25 51 873 203 4041(6) 2059 2539 39 808 23 104 708 82 5220Note:(4),(5),and (6) are average responses at pseudo steady—state (6—14 to 6—28, 1988; 5—10 to 5—17, 1988:12—30 to 01—08, 1989) for alternatives 1, 2. and 3 respectively.TableB2.5ResponseDataof SamplingPoint No.5UnderDifferentAcclimatizationAlternativesAcclim.DateDaysSolids,mgILSolids,%v%TSCOD,mgILInoiganics.rnglLPJter.TSVSTSSTVSSTotalaol.NH4-NTKNTPPO4-PI%1I%TSI1%]l%TS)(1)03/28/881559033005204800.5659.030.0580.00118791058627738020116004/04/888478026708206900.4855.860.0884.15104801053729044017517004/08/8812511031405004800.5161.450.0596.001152894822684361901340411218816492030007205900.4960.980.0781.94118681116827549222716004/1518819567027005905400.5747.620.0691.5310873507426728220914904/19/8823474039406504500.4783.120.0769.23112701016923235120319204/23/8827565035708907100.5763.180.0979.7812455969624528223220104/26/8830515031008704900.5260.190.0773.13117811040524334023220504/30/8834519029305604400.5256.450.0678.57120151120928530714020105/03/8837527031505504200.5359.770.0678.36118541040325240420220205/0718841517030505103800.5258.990.0574.5111592979628731620019905/10/8844541030204603300.5435.820.0571.74115171086128033320618605/14/8848572033806805700.5759.090.0783.82125381083224532520819305/17/8851343013908905900.3440.520.0785.511199210463281291188199(2)05/31/88119701940166014200.2098.480.1782.547232505131938519611106/07/8885240274013804900.5252.290.1435.519376873239439621020006/14/881544202830120420.4464030.0135.2010653930733741220820806/2118822612542055203940.6188.650.0575.8010240872028930419417806/28/8829711542408907900.7159.590.0988.76114639837264299199188(3)11/15/8817430453710337800.7461.080.1075.51129841177936544321721311/18/884678739279005760.6857.860.0964.00122221095233539520219511/22/888720845205204960.7262.710.0595.38117511058431944121219811/25/8811631036464634350.8357.780.0593.95110481104831745523021011)29/881571734373121311530.7260.960.1295.0512160960032142219918712/02/881844832303•5574930.4551.370.0888.5110283971731332217117912/06/8822698544155384830.7063.210.0589.7810688931227431417716812/09/8825648336535535080.6556.350.0691.86103941007924530218617612113/8829735745006986430.7461.170.0792.1211181960621526117417112/16/8832873740676005630.8760.370.0693.83117091013824028718718012/20/88367700523310039430.7787.980.1094.02133331136130437021119412/23/883978405107150314050.7666.850.1593.48134941084365141222219812/27/88437737518010389680.7766.950.1093.26129601096033139020219012/30/8846686342908005530.6962.510.0692.17119841063535144219918601/03/8950846039308838180.6580.840.0790.4811089986335135416317901/06/895381775615157414630.8268.670.1692.951410411394343474222201(4)48485325978104970.4845.140.0680.361201510719269318200193(5)22588737585104090.5964.090.0566.59107859288290338200191(8)50716748129528780.7264.000.1091.871239210564348423195189-3 t’3173Table 82.5 Response Data of Sampling Point No.5 Under DifferentAcclimatization AlternativesAcci. Date Days VFA . mg/L Tot.VFAAlter. HAc HPr iso- HBr A - HVr iso- HVr HHe mgIL HAcHBr HVr(1) 03/28/88 1 1051 512 28 346 172104104188 8 2059 1602 34 1371 696 472504/08/88 12 1837 1407 31 1433 724 440204/12188 16 2067 1833 33 1706 871 525104/15/88 19 1423 1291 31 1270 656 374304/19/88 23 1560 1626 24 1323 660 418504/23/88 27 1932 2151 28 1110 12 2 629 92 489104/26/88 30 2076 2461 30 1072 14 32 593 77 523804130188 34 2046 2420 31 1226 16 37 642 3 527505/03/88 37 1894 2193 32 1247 17 39 663 3 496805/07/88 41 1777 1856 32 1190 18 39 644 3 452905/10/88 44 1961 2032 38 1372 21 48 755 4 505705/14/88 48 2073 2191 39 1414 22 49 817 4 536405/17/88 51 1970 2049 37 1336 22 48 780 5 5070(2) 05/31/88 1 864 911 32 531 21 44 399 55 228806/07/88 8 1125 1404 42 805 25 50 692 151 337006/14/88 15 935 1771 54 1136 32 65 960 241 392906/21/88 22 1380 1823 37 1065 22 47 874 179 425706/28/88 29 2037 2262 32 1135 19 46 862 162 5296(3) 11/15/88 1 2069 2402 68 1112 32 91 643 130 533911/18/88 4 2068 2295 59 1093 28 81 625 111 520311/22188 8 2094 2210 53 1132 25 74 637 111 518411/25/88 11 2256 2331 65 1191 29 77 724 105 554511/29/88 15 2101 1966 57 964 27 65 622 91 485812/02/88 18 2205 2066 52 933 24 60 571 84 498012106/88 22 2210 2133 38 958 531 493112109188 25 2339 2219 36 . 966 540 513912/13/88 29 2247 2243 893 512 497612116/88 32 2322 2404 916 544 521612120/88 36 2536 2693 38 1092 76 146 862 82 617012123/88 39 2231 2572 49 1074 75 154 855 92 576712/27/88 43 2418 2490 39 1046 56 133 798 92 580512/30/88 46 2323 2324 40 966 105 754 87 544401/03/89 50 2186 2513 51 880 114 729 83 539701/06/89 53 2508 2920 48 995 29 120 760 78 6162(4) 48 2001 2091 38 1374 22 48 784 4 5164(5) 22 1451 1952 41 1112 24 53 899 194 4494(6) 50 2339 2586 46 947 29 113 748 83 5667Note (4)(5) and (6) are average responses at pseudo steady-state (6-14 to 6-28 1988 5-10 to 5-17 198812-30 to 01-06. 1989) for alternatives 1, 2, and 3 respectively.Table82.6ResponseDataof SamplingPointNo.6UnderDifferentAcclimatizationAlternativesstchm.DateDaysSolids,mgILSOlids.mgILCOD. mgIL.Inorganics. mg/IAlter.TSVSTSSWSTotalSolubleNH4—NTKNTKNTPTPP04—P%Jl%TSII%1I%TSIl%TSIl%TSI(1)03128/881457028606004700.4658.210.0678.33424239192772795.791131.023204/04/88880605000193014000.8162.030.1972.54776072312832673.891191.038504/08/881274204230175012700.7457.010.1872.57747956812292823.961560.918004/1218818649037409306600.6557.630.0970.971075149172352964.111500.919604/15188196570393011607500.6659.820.1264.86558638802552572.851341.215904/19/882363403780186012800.6359.620.1968.82542328812282572.831271.885204/23/882763503810219015700.6456.860.2271.69523428802702862.742051.953604/261883060203170172012000.6052.660.1769.77506121462782863.321381.9835041301883478204610344025200.7660.500.3473.26717731452413072.472112.985305/031883789104030288021700.6958.320.2975.35572523392702582.851292.874305107/884178604770425031300.7960.690.4373.6557968982652793.621172.613005/10/884481304790513037100.8158.920.5172.32876211062823033.511292.7610051141884894705900837046500.9562.300.6472.9963498952792843.88282.882305/1718851107106750786057501.0763.020.7973.1598199252862914.06502.449(2)05/31/88153903850192016500.5471.430.1985.94400031922772906/07/8884340204013103300.4347.000.1325.19261618912854706/14/88153570185010903280.3651.820.1130.10170310692993121.78803.554206/21/88225830368011906050.5863.120.1250.80280016002923161.54922.003706/28/882957952920214012850.5850.390.2159.11292711382492532.19864.5514(3)11/15(881388521408304770.3955.080.0857.47490144274285673.441254.322411(18/884524029409975870.5256.110.1058.88619047824184702.081313.112911/22/8885185311010877700.5259.980.1172.16575943583934892.741383.084711125/881159003425248018100.5958.050.2572.98524128234025043.00.1202.822211/29/881583703620311021700.6456.830.3169.77560028403734892.851183.122712102/881893255630369022900.9360.380.3762.08489610533783502.63313.161412/06/882259832937320019900.6049.250.3262.1936448913653422.91905.022712)091882571003610418023700.7150.850.4256.7043318683263633.021024.87612113/882968053130379022500.6846.000.3859.3738587872963263.281486.432912116/883255502625263017400.5647.300.2886.1629869432803032.521328.064312/20/883662503480284020500.6355.680.2872.18512823673243242.971304.007712/23/883961053410294020300.6155.860.2969.05530126513573692.991293.45512)27/884369553910346024800.7056.220.3571.68616023203763383.301083.791512/30)884667653720311022400.6854.990.3172.0351598734083913.531003.574401/03/895064303505382025400.6454.510.3866.49467315054144373.541044.422501/06(895380853375389025800.6155.460.3769.9241435583664794.35415.628(4)94375813645347030.9461.410.6572.8276439752822933.82692.6314(5)5065281714737330.5155.110.1546.87247712692802941.84793.3731(6)84273533354024530.6464.990.3569.4846589793964363.81824.5426I-’175Table B6 Response Data of Sampling Point No.6 Under Different Acclimatization Alternatives (contd)Acci. Date Days VFA, mg/L TC.VFAAlter. HAc HPr leo- HBr A-HVr leo- HVr HHe mg/I.. HAcHBr HVr(1) 03/28/88 1 1780 1172 25 1029 344904/04/88 8 2062 1053 55 496 315 347704/08/88 12 1479 912 44 329 222 260304/12188 16 1065 1144 55 241 225 232704/15188 19 345 1003 39 80 125 131304/19/88 23 92 1424 41 127504/23188 27 172 1359 32 10 14 131104/26/88 30 69 1664 32 6 15 145304/30/88 34 255 1466 25 11 24 149205/03/88 37 277 1058 21 9 24 117005/07I88 41 131 277 35605/10/88 44 218 178 36005114188 48 216 227 40005117/88 51 193 186 344(2) 05/31I88 1 415 540 32 155 18 25 188 27 113006/07/83 8 398 447 12 17 27 79306/14/88 15 89 35 11706/21/88 22 236 484 16 5 17 65106/28/88 29 359 361 17 662(3) 11/15/88 1 819 811 44 278 18 31 241 150311/18/88 4 886 962 56 259 28 56 335 212711/22/88 8 1236 80 73 30 67 190 126211/25/88 11 407 978 56 30 63 34 131311/29/88 15 252 584 57 984 12 55 14 146912/02/88 18 122 146 11 24712/06/88 22 198 16112/09/88 25 133 10812/13/88 29 266 21612)16/88 32 104 155 23012)20/88 36 96 114.3 19 59 117 81 118712123188 39 101 1396 19 16 34 127512/27/88 43 95 1301 13 48 137 126812130/88 46 92 819 12 23 100 83701/03/89 50 201 4.37 10 29 174 68401/06189 53 63 123 2 164(4) 208 197 368(5) 228 293 18 5 17 477(8) 119 460 8 29 23 137 562Note:(4),(5),and (6) are average responses at pseudo steady—state (8—14 to 8—28, 1988:5—10 to 5—17. 198812—30 to 01—06, 1989) for alternatives 1,2. and 3 respectively.176Table B2.7 Response Data of Sampling Point No.7 Under Different Acclimatization AlternativesAcclim. Date Days Solids, mg/I COD. mg/I lno.ganics, mg/IAlter. TSS VSS (%j %TS) Total Sd. NH4-N TKN TP 04-P(1) 03128/88 1 900 690 0.09 76.67 4404 2788 277 286 113 2504/04/88 8 920 610 0.92 66.30 6080 5520 290 320 116 5604/08/88 12 530 360 0.05 67.92 4752 5578 242 240 252 6604/12/88 16 730 520 0.07 71.23 5834 5000 235 312 400 5904/15/88 19 840 610 0.08 72.62 4562 4136 245 156 150 4504/19/88 23 850 570 0.09 67.06 4152 3305 245 156 150 4704/23/88 27 1000 670 0.10 67.00 3773 32Q5 270 278 138 3804/26/88 30 770 460 0.08 59.74 3765 3036 272 286 138 4404/30/88 34 1070 810 0.11 75.70 4435 3064 303 319 139 4705/03/88 37 750 630 0.08 84.00 3226 2258 278 292 146 4405/07/88 41 1240 1220 0.12 98.39 2041 816 275 296 129 3005/10/88 44 870 540 0.09 62.07 1926 1004 294 313 132 2205/14188 48 1120 850 0.11 75.89 2150 832 279 298 76 3205/17/88 51 940 370 0.09 69.15 1730 724 284 284 46 13(2) 05/31/88 1 3120 2590 0.31 83.01 4566 2222 290 349 54 3606/07188 8 1530 390 0.15 25.49 2616 1891 288 329 76 4506/14/88 15 500 160 0.05 32.00 1386 990 282 332 88 3306/21/88 22 650 406 0.07 62.50 2000 1120 287 316 90 3306/28/88 29 595 350 0.06 58.82 1707 1138 237 261 70 28(3) 11/15/88 1 893 568 0.09 63.61 5296 4190 451 575 116 3411/18/88 4 745 370 0.07 49.66 4286 3492 464 477 118 2411/22188 8 205 190 0.02 92.68 3658 3580 438 567 133 4911/25188 11 478 323 0.05 67.57 2823 2339 402 523 124 3811/29/88 15 860 523 0.09 60.81 2960 1920 392 494 105 1512102188 18 677 417 0.07 61.60 1619 971 387 410 66 1412/06/88 22 780 483 0.08 61.92 1377 729 365 362 90 2212109/88 25 930 560 0.09 60.22 1575 1024 326 339 84 1212113/88 29 875 475 0.09 54.29 1181 1024 300 326 126 2012116/88 32 857 490 0.09 57.18 1375 668 275 287 112 2312120/88 36 810 500 0.08 61.73 2288 1775 294 329 120 2712123/88 39 740 440 0.07 59.46 2691 1285 338 338 117 2612/27/88 43 1080 720 0.11 66.67 2760 2160 312 377 112 912/30/88 46 690 530 0.07 76.81 1151 754 376 377 97 501/03/89 50 785 490 0.08 62.42 1228 950 338 359 176 901/06/89 53 370 207 0.04 55.95 916 398 171 459 75 4(4) 977 587 0.10 69 1935 853 286 298 85 22(5) 582 305 0.06 51 1698 1083 269 303 83 31(6) 615 409 0.06 65 1098 701 295 398 116 6177Table B2.7 Response Data of Sampling Point No7 Under Different Acclimatization Alternatives (cont’d)Acclim. Date Days VFA, mg/I Tot.VFAAlter. HAc HPr iso- HBr A-HVr Iso- HVr HHe mg/L HAcHBr HVr(1) 03128188 1 698 284 154 103304/04/88 8 1615 692 38 305 170 251004/08/88 12 1775 914 47 284 186 285104/12188 16 904 955 46 208 171 195204/15/88 19 381 1063 42 83 135 140804/19/88 23 90 1502 44 133804/23/88 27 118 1652 39 28 18 151304/26/88 30 76 1459 29 5 11 128804/30188 34 169 1379 23 39 20 134105/03188 37 204 969 19 35 19 103805/07/88 41 103 297 7 34905/10/88 44 174 146 25 30905/14/88 48 130 156 10 26305/17/88 51 115 114 10 214(2) 05/31/88 1 287 295 55 11 12 69 61806/07/88 8 464 518 21 30 19 19 33 96106/14/88 15 72 298 27 23 34606/21/88 22 136 362 43006/28/88 29 254 302 26 22 530(3) 11/15/88 1 587 290 34 126 12 25 139 103511/18/88 4 820 572 46 105 18 41 160 151611/22/88 8 996 769 54 27 48 60 173611/25/88 11 560 700 54 19 57 14 121711/29/88 15 585 533 120 20 111112/02/88 18 186 56 10 23712106/88 22 60 4912/09/88 25 68 5512/13/88 29 104 189 28 27612/16/88 32 78 48 11712/20/88 36 44 853 13 87 52 82612/23/88 39 134 1259 16 35 52 122012/27/88 43 85 824 7 26 42 80012/30/88 46 56 650 7 38 61001/03/89 50 118 219 4 18 143 39501/06/89 53 53 46 90(4) 140 139 15 262(5) 154 321 27 23 435(6) 76 305 6 18 91 365Note: (4), (5). and (6) are average responses at pseudo steady—state (6—14 to 6—28. 1988; 5—10 to 5—17. 1988: 12—30 to 01—06, 19for alternatIves 1, 2, and 3 respectively.Table BZ8 Response Data of Sampling Point No.8 Under Different Acclimatization Alternatives (contd)Acci. Date Days VFA. mg/I Tot. VFAAlter. HAC HPr iso.- HBr -HVr iso- HVr HHe mg/I HAcHBr HBr178( 1 )0 3 1 2 8 / 8 81 2 0 5 1 1 4 1 70 4 / 0 4 / 8 882 1 0 88 8 30 4 / 0 8 / 8 81 22 2 2 91 1 3 50 4 / 1 2 / 8 81 69 7 7 1 0 7 20 4 / 1 5 / 8 81 91 1 8 2 1 3 5 30 4 / 1 9 / 8 82 33 31 3 0 40 4 / 2 3 / 8 82 77 51 6 5 90 4 / 2 6 1 8 83 08 8 1 3 7 10 4 / 3 0 / 8 83 4 1 0 59 5 50 5 / 0 3 ) 8 83 71 0 7 7 1 30 5 / 0 7 / 8 84 19 72 1 40 5 / 1 0 / 8 84 41 2 29 60 5 / 1 4 / 8 84 81 2 41 3 60 5 1 1 7 1 8 85 1 9 08 3( 2 ) 0 5 / 3 1 ) 8 81 2 3 51 7 40 6 / 0 7 / 8 882 0 02 4 40 6 ) 1 4 / 8 81 55 71 4 60 6 / 2 1 / 8 82 29 5 2 3 50 6 / 2 8 ) 8 82 9 1 9 52 4 1 )( 3 )1 1 1 1 5 / 8 814 1 26 81 1 / 1 8 / 8 848 3 51 8 81 1 / 2 2 / 8 888 3 46 8 91 1 / 2 5 / 8 81 14 2 38 1 31 1 / 2 9 / 8 81 53 0 86 6 61 2 ) 0 2 1 8 8 1 81 4 22 1 11 2 1 0 6 / 8 82 2 001 2 / 0 9 / 8 82 5001 2 ) 1 3 1 8 82 90 01 2 / 1 6 / 8 83 2001 2 / 2 0 / 8 83 6 4 48 9 51 2 1 2 3 / 8 83 95 71 2 0 71 2 ) 2 7 / 8 84 35 91 0 4 51 2 1 3 0 ) 8 84 64 85 7 10 1 / 0 3 / 8 95 05 09 90 1 / 0 6 / 8 95 . 33 62 3( 4 )4 81 1 21 0 5( 5 )2 21 1 6 2 0 7( 6 )5 04 52 3 14 0 7 13 2 4 33 5 5 42 1 3 73 2 8 01 1 1 71 4 5 71 2 0 09 0 26 9 42 7 02 0 02 3 41 5 71 13 8 23 9 81 7 52 8 63 9 05 4 28 7 51 4 6 59 9 08 6 53 1 90000000 08 1 01 1 2 29 6 35 2 11 3 05 51 9 72 8 42 3 5N o t e : ( 4 ) , ( 5 ) , a n d( 6 )are average responses a t pseudo s t e a d y — s t a t e( 6 — 1 4 to 8 — 2 8 .1 9 8 8 ;5 — 1 0t o5 — 1 7 .1 9 8 8 ;1 2 — 3 0t o 0 1 — 0 6 ,1 9 8 9 ) fora l t e r n a t I v e s1 ,2 ,and3r e s p e c t w e l y .2 9 1 2 4 95 0 3 6 62 3 12 3 16 1 3 3 02 3 52 3 55 2 2 0 81 9 31 9 32 5 1 0 1 3 4 9 94 9 93 94 0 1 62 881 58 1 23 1 262 62 51 56 93 82 91 23 06 05 12 15 04 35 3 2 41 75 51 31 44 81 51 0000000 0000000000 00 001 39 25 362 51 1 51 57 91 41 4Table82.8ResponseDataofSamplingPointNo.8UnderDifferentAcclimatizationAlternativesAcclim.DateDaysSolids,mg/I..Solids.%or%TSCOD.mg/I.Inorganic.. mg/I.Alter.TSVSTSSTVSSTotalSd.NH4—NTKNTPP04—PI%1(%TSI(%J(%TS(1)03/28/881358022806603600.3663.690.0754.55.272728692583981905804/04/888522026404002300.5250.570.0457.50536049802802711085804/08/8812835034202601900.8453.860.0373.0855785351229236150660411218816610036504302900.8159.840.0487.4450844917237294154700411518819606035108704100.8057.920.0781.19430725372352321604504/19/8823502028705303800.5057.170.0571.69398330082351501523804/23188275520296010907400.5553.620.1167.89385428602642971302404/26/883060303420213015400.6056.720.2172.30506l25302642751303204/30/883446702290205316040.4849.030.0672.73322524192722891244305/03/883776004460377028700.7658.680.3878.13604817742652291143505/07/884148302740174013600.4856.730.1778.1823677352873091042205/1018844461022907804900.4649.870.0882.8217827992943261171605/14/8848384020108605400.3852.340.0962.791744791284298541905/17/8851626039208705500.6382.620.0983.221589684291286508(2)05/31/88141303220130012900.4177.970.1399.2327071515306356503606/07/8884010185012803000.4048.130.1323.4420521268282318703606114/881527901230120600.2844.090.0150.00911851274296722806121/8822398016122601690.4040.500.0365.0011209202843129023061281882992102850115850.9230.940.0173.918948132542807817(3)11/1518813260187010105800.3357.360.1057.43395326884716121004711/18/884322518557203200.3251.320.0744.44309525404385181043411/22/888344219163221700.3455.870.0352.80350224124385531224211/25/8811391520953401900.3953.510.0355.8824192258392533.1181211/29/8815359617834702700.3649.580.0557.4523201920364485922712/02/8818316713002631380.3241.050.0352.471053891374370551212)06/8822324312633931970.3238.950.0450.13574486357378881212/09/8825334513353731880.3339.910.0450.40866709322351841212/13/8829335511604372000.3434.580.0445.777095512963351161412/18/8832340310373171570.3430.470.0349.537075892802871031412/20/8836377714904272100.3839.450.0449.18193318543044621462612/23/8839390918573801930.3942.390.0450.7922891847274330102512/27/8843391717173501130.3943.830.0432.292040204035133880512/30/8848350713002571770.3537.070.0368.8713091032370400781501/03/8950326010703701770.3332.820.0447.8471355439539170501/06/89533020933203700.3030.890.0234.48438359394479737(4)490327408375270.4954880.0962.9416927582903037414(5)532718971651050.5338.510.0262.979758612712967923(6)326211012771410.3333.590.0350.408208483864237393(o coo>.c E a ‘I 0 a-U) U)Ox: 0b2.62.21.81.4 10.60.2 80 70-60-50-40-30 20-10-0-E a I—1121927344)48115Ti,no(lilys29411182532394653FigureBi.1Effluent QualityoftheM-UASB:Duringthencclimatizationunderdifferentrunningconditions:(a)A-UASBandM-UASBseededwithUonGatesludge;(b)M-UASBseededwithacclimatizedsludge;(c)M-UASBseededwithLionGatesludge00 00 E I 0FigureB2.1SystemGasProductionandLoadingRateDuringacclimatizationunder differentrunningconditions:(a)A-UASI3andM-UASBseededwithLionGatesludge;(b)M-UASBseededwithacclimatizedsludge;(c)M-UASBseededwithLionGatesludge80 60 40 20 9 7.--5-3-C 0 0 I. 0. (3/-----4-—A-UAS1-M-UASO(a)—-“‘--(Li)”’‘“‘‘-(c)—-—-—-v-_.\_____-_____-__--—-_-_zr-—-----r-/\—Cu.mkgVSromov9dCu.m/kgCOD:__1— 8 7— 6— 5—C4- -32— 1— 0-121927344148KgCOofror )lcu.m-dKgVS)cu.m-d1529411182532394653Timo,(laysCo182APPENDIX COptimum ‘best known” Operating ConditionTable C1.1-C1.8 : Response Data of the Sampling Point Numbered 1 to 8 UnderDifferent Running Conditions During the Sequence 1, 2, and 3 Experiments.Table C2.1 Calculation of the effects (SR and RR), Interaction, Phase means, Changein means, on the Response Parameters during the Acclimatization (Sequence 1, 2, and3 Experiments).Table C3.l : pH of A-and M-UASBs During the Sequence 2 and 3 Experiments as wellas the Maximization and Recovery PeriodTable C3.2 : NaOH (0.1 N) Addition During the Sequence 1 ExperimentNote : All sampling locations are illustrated in Figure 4.2TABLECLIRESPONSEDATA(SAMPLINGPOINTNUMBERED1)UNDERDIFFERENTRUNNINGCONDITIONSDURINGPHASE1,2,AND3EXPER.RUNDAYDATESOLIDS,MG/LorELSECOD,MG/LINORGANICS,MG!LorELSENUMBERSTSVSTSSTVSS[%][%TSJ[%J%TS]TOTALSOL.NH4—TKN[%TSITP(%TSIP04-P[1].F5,SR8O/20,107/12/88485334442745500433004.8591.544.5595.16758645149182764.061711.06169RR214807/19/88439804045538250364204.4091.983.8395.22872304951202453.751580.91110II07/22/88502554638048180460805.0392.294.8295.64471954487182674.041650.88136[2].F5,SR8O/20,1507/26/88467604304042510407604.6892.044.2595.88434618450182584.621851.21168RR6/I02208/02/8833655293f27260250603.3787.242.7391.93317277430502704.271671.15134[07/30/88]2908/09/88410953655031520286704.1188.943.1590.96444888645522964.271361.311123208/12/88279152493022180210902.7989.312.2295.09628007800502824.561681.241403608/16/88360003297027270263203.6091.582.7396.52510986786302273.961510.891283908/19/88328103006526580257003.2891.632.6696.69413527157232694.081550.991314308/23/88346203159525724249783.4691.262.5797.10457596233182924.231750.971364608/26/88350503212528130274903.5191.652.8197.72385096501322774.081750.85147[31.F5,SRSO/50,4908/29/88281192562533620328002.8191.133.3697.56462178793422814.361860.89173RR6/105309/02/88284752583518960187702.8590.731.9099.00387637256393784.692180.63189[08/31/88]5709/06/88170801544716310160801.7190.441.6398.59302667689314294.532220.941916009/09/883534.03213527790266803.5390.932.7896.01421497107414644.782311.441806509/14/88495454521034140326804.9591.253.4195.72477377654214724.312141.261786809/17/88378253475529570286103.7891.882.9696.75344268115504774,432441.231937109/20/88304302723020580199303.0489.482.0696.84383676449424434.322041.101697409/23/88292952627528350269902.9389.692.8495.20406505935594853.451921.121617809/27/88420453842034390332404.2091.383.4496.66522096827684623.622450.861898109/30/88450254075551830490504.5090.525.1894.64476196270394803,.332200.83177[4J.F5,SRSO/50,8510104/88326002902026400251903.2689.022.6495.42339396426344733.741941.08163RR2/49510/14/88324952933024250231303.2590.262.4395.38411076324234944.522301.50181[10/03/88]9910/18/88284002516519930189802.8488.611.9995.23384006250285015.292171.6917810210/21/88287452564033960319702.8789.203.4094.14376006320145214.692121.56166[5].F5,SR7O/30,I01/17/89256852256021470201202.5787.832.1593.71357777801534345.042251.81182RR3/6801/24/89271902396019800184602.7288.l21.9893.23373246761546226.122522.59247[14/01/88]1501/31/89337703068028300271603.3890.852.8395.97353315931414584.701741.261542202/07/89360653273531090295703.6190.773.1195.11402176087774164.431971.281582502/10/89374003371530240285603.7490.153.0294.44626026179564674.572021.271652902/14/89365253314029920286303.6590.732.9995.69258066532824093.792170.96182I-’TABLECI.1RESPONSEDATA(SAMPLINGPOINTNUMBERED1)UNDERDIFFERENTRUNNINGCONDITIONSDURINGPHASE1,2,AND3EXPERIMENTEXPER.RUNDAYDATESOLIDS,MG/LorELSECOD, MG/LINORGANICS,MG/LorELSENUMBERSTSVSTSSTVSS[%][%TSI[%][%TS]TOTALSOL.NH4-NTKN%TS]TP%TSIP04-P[6].F5,SR7O/30,4301/14/00260252324520450194002.6089.322.0594.87370816469574444.951741.33149RRS/85001/21/00402653658531140300503.0290.483.1196.50509097354674784.852571.48198[02/20/89]5701/28/00301852731023350225004.0390.862.3496.36514297184444134.771971.481596402/04/00264202399525400244503.0290.482.5496.26433736667264404.611991.181677102/11/003627533310328903)0402.6490.823.2994.38373336578253853.542000.92185[7].F5,SR6O/40,7802/18/00224701972023260219403.6391.832.3394.33409846967254774.382021.40175RR5/88502/25/00324052921029010277402.2587.762.9095.62381347789214234.242331.30218[03/29/89]9203/03/00263052336522550218103.2490.142.2696.72297797082254963.872181.321959903/10/00282402544023840229702.6388.822.3896.35308918951105614.922331.7218210203/13/00256952290524350232302.8290.082.4495.40378336918124064.251831.1917310603/17/00328803027823760223402.5789.142.3894.02504938126214174.942091.20182[8].F5,SR6O/40,11303/24/00371653376033290314703.2992.093.3394.53360787216195015.7225)1.47210RR3/612003/31/00310)02810027410262303.7290.842.7495.70506937446285075.122260.87194[05/09/89]13004/10/00200451754513390128903.1090.621.3496.27408647151205425.142271.2318513404/14/0034)353138533230320202.0087.533.3296.3639766764!245233.592350.9517513704/17/0028)302546520040194103.4191.942.0096.86308887490154455.301791.0818014104/21/00280502527518610180702.8)90.531.8697.10362237245105)05.052183.22167[9].F5,SR8O/20,106/13/89297552689521470209202.8)90.112.1597.44363616679173655.441640.98146RRS/8806/20/89316102856518270178202.9890.391.8397.54464737137123165.241501.05141[06/10/89]1506/27/89290002594522770214203.1690.372.2894.07607297935104)45.382090.98164[10].F5,SR8O/202207/04/89322502879538230365502.9089.473.8295.6131014675983535.091950.76161RRS/82907/11/89397303618033740321903.2389.293.3795.41590827425273665.122001.04163[07/02/89]3607/18/89319352881028170266603.9791.062.8294.64509806902433453.991920.81160Reacclimatizatio4307/25/89255552283025090241103.1990.212.5196.09560006080453304.771670.961324607/28/89258752289524150229702.5689.342.4295.11370375778232784.241520.861305008/01/89297652667028050263302.5988.482.8193.87382354926292175.1)1101.1310)5308/04/89275402456531490294802.9889.603.1593.62390855073392654.941471.21121TABLECI.)RESPONSEDATA(SAMPLINGPOINTNUMBEREDI)UNDERDIFFERENTRUNNINGCONDITiONSDURINGPHASE1,2,AND3EXPERIMENTEXPER.RUNDAYDATESOLIDS,MG/LorELSECOD,MG/LINORGANICS.MG/LorELSENUMBERSTSVSTSSTVSS[%][%TSI[%][%TS1TOTALSOL.N114—TKN%TSJTP%TSJP04-P5650392415.831560.751315447333374.882961.071215656243434.732900.781035944345474.242261.041236800245213.882370.941606270242764.361510.941235992182554.551411.041386705242834.371770.851655691542624.461371.001425971502814.061640.661426504392783.521770.741566033242784.321511.23135NOTE1,212AREAVERAGERESPONSESATPSEUDO—STEADYSTATEFOREXPERIMENTALRUNNINGCONDITIONSNUMBEREDITO12RESPEC[11].F5,SR9O/10,5708/08/89380153474533450318902.7589.203.3595.3450224RRS/86408/15/893046026955,25430237903.8091.402.5493.5532340[08/05/89]7108/22/89468004194539560372203.0588.493.9694.08483617808/29/89399103624037820359504.6889.633.7895.06248998109/01/89348453153032710308703.9990.803.2794.37464008509/05/89327102930534620330803.4890.493.4695.5548413[12].F5.SR9O/I0,9209112/89301952704524550234303.2789.592.4695.4435020RR3/69909/19/89352153203036350348103.0289.573.6495.7659345[09/06/89]10609/26/89323202917531330298703.5290.963.1395.344248510909/29/89302952738529520281303.2390.272.9595.295153411310/03/89342653135232240315603.0390.393.2297.893139811610/06/89320902807033720310203.4391.503.3791.99413221469984329242980410874.7092.114.3095.58592955963192574.141691.001382325962978229158284233.2691.352.9297.46434957176312834.221790.901523387883515038190364273.8890.533.8295.50468266344554763.472190.941764298802671226047246932.9989.362.6094.92390366298225054.832201.581755366633319730417289203.6790.553.0495.0842875626672431.4.262051.171686313482865329145277452.8390.652.9195.32403536623264134.082001.051767319132898127133256802.8990.442.7194.65414687420174414.972141.161808280902537019325187403.1191.231.9396.98335567368134785.181992.151749303052725520520196203.0790.382.0595.80536017536II3655.311801.3120710277272471027897262602.7189.142.7994.20381195259302534.761361.52189Ii358223235835050333004.0590.313.5194.99399046338274484.162051.4617812322172893631827302373.2390.723.1895.06414186169382793.971640.88144I-’ do rn1 8 6T A B L EC I .1R E S P O N S ED A T A ( S A M P L I N GP O I N T N U M B E R E D1 ) U N D E RD I F F E R E N TR U N N 1 NC O N D I T I O N SD U R I N G P H A S E1 , 2 ,A N D3E X P E R I M E N T SE X P E R . R T J ND A Y D A T EV F A .M G / LT O T . V F AN U M B E R S H A c H P r i s o -H B rA - H V r I s o — H V rH H e m g I LH A cH B rH V r[ 1 ] . F 5 , S R 8 O / 2 0 .1 0 7 / 1 2 1 8 84 2 61 4 38 9 6 0 3R R 2 / 48 0 7 / 1 9 / 8 8 5 1 2 2 9 41 1 78 3 01 1 0 7 / 2 2 / 8 85 8 0 3 7 11 1 7 9 6 1[ 2 ] . F 5 , S R 8 O / 2 0 , 1 5 0 7 / 2 6 / 8 8 1 3 1 8 2 1 7 52 8 53 2 7 6R R 6 / 1 02 20 8 / 0 2 / 8 8 5 9 4 4 7 22 2 7 1 7 7 62 1 7 6[ 0 7 / 3 0 / 8 8 ]2 90 8 / 0 9 / 8 8 2 9 72 31 5 59 8 81 0 0 33 2 0 8 / 1 2 / 8 85 7 93 02 7 2 1 6 98 8 83 60 8 / 1 6 / 8 85 5 1 5 31 4 11 7 67 9 43 9 0 8 / 1 9 / 8 86 2 18 68 1 1 6 0 8 4 04 30 8 / 2 3 / 8 85 6 1 2 6 16 0 2 3 3 1 4 6 1 0 3 64 60 8 / 2 6 / 8 86 1 23 2 17 32 0 9 1 0 4 5[ 3 j . F 5 , S R 5 O / 5 0 , 4 9 0 8 / 2 9 / 8 88 4 1 5 5 61 3 73 3 9 1 5 8 5R R 6 / 1 05 3 0 9 / 0 2 / 8 87 2 84 9 59 73 3 7 1 3 9 4[ 0 8 / 3 1 / 8 8 15 7 0 9 / 0 6 / 8 87 0 92 8 81 2 43 1 81 2 1 46 00 9 / 0 9 / 8 84 4 8 1 5 11 1 4 1 9 01 77 7 06 50 9 / 1 4 / 8 83 8 81 0 18 83 6 5 5 16 8 0 9 / 1 7 / 8 85 5 1 2 2 51 6 02 5 33 41 0 1 17 10 9 / 2 0 / 8 82 6 19 853 31 4 3 7 27 40 9 / 2 3 / 8 82 2 21 0 1 1 23 1 17 80 9 / 2 7 / 8 86 2 23 9 1 3 14 82 2 1 0 0 18 1 0 9 / 3 0 / 8 83 5 02 1 32 06 71 55 8 5[ 4 1 . F 5 , S R S O / 5 0 , 8 5 1 0 / 0 4 / 8 82 4 81 4 52 51 23 8 7R R 2 / 49 51 0 / 1 4 / 8 84 8 33 8 35 15 52 48 7 5[ 1 0 / 0 3 / 8 8 ]9 9 1 0 / 1 8 / 8 8 3 6 82 2 83 23 496 0 01 0 21 0 / 2 1 / 8 83 4 02 0 03 11 75 3 3[ 5 ] . F 5 , S R 7 O / 3 0 , 1 0 1 / 1 7 / 8 98 5 41 5 2 71 6 61 2 72 2 8 0R R 3 / 680 1 / 2 4 / 8 95 7 99 1 81 5 31 9 41 5 4 2[ 1 4 / 0 1 / 8 8 ]1 50 1 / 3 1 / 8 95 1 07 7 76 29 . 51 1 8 82 2 0 2 / 0 7 / 8 98 6 61 2 7 58 34 41 9 8 22 50 2 / 1 0 / 8 97 3 6 1 3 0 46 1 3 01 8 5 32 90 2 / 1 4 / 8 99 9 7 1 6 0 71 2 6 4 92 4 1 5[ 6 ] . F 5 , S R 7 0 1 3 0 ,4 30 2 / 2 8 / 8 95 5 18 0 84 7 1 2 3 8R R S / 85 00 3 / 0 7 / 8 91 1 2 2 1 7 3 21 1 24 52 6 2 9[ 0 2 / 2 0 / 8 9 ]5 70 3 / 1 4 / 8 97 6 11 2 5 37 58 01 8 7 56 40 3 / 2 1 / 8 95 6 8 9 0 56 5 1 31 3 5 47 10 3 / 2 8 / 8 91 0 5 91 4 7 01 3 23 92 3 6 4[ 7 ] . F 5 , S R 6 O / 4 0 .7 80 4 / 0 4 / 8 94 5 5 7 7 66 74 91 1 5 9R R S / 88 50 4 / 1 1 / 8 93 4 93 7 55 42 27 0 3[ 0 3 / 2 9 / 8 9 ]9 20 4 / 1 8 / 8 96 3 1 1 1 3 57 64 11 6 2 79 90 4 / 2 5 / 8 94 3 68 5 36 75 01 2 0 31 0 2 0 4 / 2 8 / 8 93 5 05 5 55 04 18 5 81 0 60 5 / 0 2 / 8 94 1 6 6 7 45 84 81 0 3 01 8 7T A B L E C 1 . 1 R E S P O N S E D A T A( S A M P L I N G P O I N T N U M B E R E D 1 )U N D E R D I F F E R E N TR U N N I N G C O N D I T I O N SD U R I N G P H A S E1 , 2 .A N D 3 E X P E R I M E N T SE X P E R . R U N D A Y D A T EV F A , M G / I .T O T . V F AN U M B E R S H A c H P r I s o —H R r- H V rI s o -H V rH H eg / L H A cH B rH V r[ 8 ] . F 5 , S R 6 O / 4 0 , 1 1 3 0 5 / 0 9 / 8 9 6 3 4 1 2 7 21 1 36 21 7 7 9R R 3 / 6 1 2 0 0 5 / 1 6 / 8 9 6 5 0 1 3 5 61 2 08 51 8 8 1[ 0 5 / 0 9 / 8 9 ]1 3 00 5 / 2 6 / 8 9 4 6 3 6 2 47 28 3 1 0 6 71 3 40 5 / 3 0 / 8 9 4 8 0 3 3 24 66 98 2 11 3 7 0 6 / 0 2 / 8 9 2 8 91 5 9 5 0 4 5 21 4 10 6 / 0 6 / 8 9 2 4 08 33 0 7[ 9 ] . F 5 , S R 8 O / 2 0 , 1 0 6 / 1 3 / 8 94 4 43 9 4 1 8 7 8 9 1R R S / 8 8 0 6 / 2 0 / 8 94 0 35 2 8 2 2 49 8 4[ 0 6 / 1 0 / 8 9 ] 1 50 6 / 2 7 / 8 9 7 4 9 1 3 9 3 3 9 11 0 2 2 2 0 5[ 1 0 ] . F 5 , S R S O / 2 0 , 2 20 7 / 0 4 / 8 9 7 4 0 1 5 6 33 2 69 92 2 8 8R R S / 82 90 7 / 1 1 / 8 96 8 31 4 3 22 3 48 12 0 5 1[ 0 7 / 0 2 / 8 9 ]3 60 7 / 1 8 / 8 97 9 2 1 6 8 12 7 31 1 82 4 1 1R e a c c l i m a t i z a t i o n4 30 7 / 2 5 / 8 97 2 11 3 8 51 8 32 1 72 0 9 64 6 0 7 / 2 8 / 8 96 3 21 3 4 11 8 08 71 8 9 35 00 8 / 0 1 / 8 95 5 9 1 1 4 41 5 58 61 6 4 35 3 0 8 / 0 4 / 8 95 6 61 2 1 11 6 59 31 7 1 5[ 1 1 ] . F 5 , S R 9 O I 1 O , 5 7 0 8 / 0 8 / 8 96 5 0 1 3 3 21 9 31 1 21 9 2 7R R S / 8 6 40 8 / 1 5 / 8 9 5 6 71 1 1 62 6 18 51 7 0 0[ 0 8 / 0 5 / 8 9 ]7 10 8 / 2 2 J 8 9 4 9 39 9 82 7 85 1 61 7 9 57 8 0 8 / 2 9 / 8 95 7 21 2 8 03 3 31 1 01 9 0 28 1 0 9 / 0 1 / 8 97 5 91 5 0 53 5 84 82 2 5 28 50 9 / 0 5 / 8 95 4 7 9 7 22 1 67 4 1 5 2 6[ 1 2 ] . F 5 , S R 9 O / l 0 , 9 20 9 / 1 2 / 8 95 8 81 2 2 42 5 45 61 7 8 7R R 3 / 69 90 9 / 1 9 / 8 9 7 6 6 1 4 4 92 9 17 42 1 8 3[ 0 9 / 0 6 / 8 9 ]1 0 60 9 / 2 6 / 8 95 3 39 1 4 1 8 23 6 1 4 1 91 0 90 9 / 2 9 / 8 94 9 78 9 61 7 83 71 3 6 71 1 31 0 / 0 3 / 8 97 1 2 1 2 9 02 4 1 6 11 9 5 81 1 61 0 / 0 6 / 8 95 0 87 8 71 4 4 2 91 2 6 1N O T E :1 , 2 , . . . . ,1 2 A R EA V E R A G ER E S P O N S E SA T P S E U D O - S T E A D YS T A T E( E X P E R I M E N T A LR U N N I N GC O N D I T I O N SN O . 1T O1 2R E S P E C T I V E L Y )18 0 39 4 71 7 31 6 8 926 7 1 3 7 99 02 6 01 4 61 2 2 233 9 82 3 52 65 81 66 3 243 9 72 7 03 84 5 1 76 6 958 6 61 3 9 59 04 1 2 0 8 368 1 41 1 8 89 92 61 8 5 977 5 7 1 1 2 31 0 04 41 7 6 182 6 51 2 15 03 8 094 9 07 5 56 53 21 1 6 51 05 3 4 9 9 47 24 6 1 4 1 51 13 9 37 0 45 94 61 0 3 01 25 7 29 9 11 8 84 21 5 2 9TABLEC1.2RESPONSEDATAOFTHESAMPLINGPOINTNUMBERED2UNDERDIFFERENTRUNNINGCONDITIONSDURINGPHASE1,2,AND3EXPER.RUNDAYDATESOlIDS,MG/LorELSECOD,MGILINORGANICS, MG/INUMBERSTSSTVSS[%][%TSITotalSol.NH4—NTKN(%TSITP[%TS1P04-P[1].F5,SRSO/20,107/12/8860290583606.0396.80127525109312802727.061990.75193RR2/4807/19/8863550611406.3696.2117288888801722236.071680.781631107/22/8849120474504.9196.607272792072082606.101750.93169[2].F5,SR8O/20,1507/26/8869990675507.0096.51121529108652313025.491850.71182RR6/I02208/02/8862360574906.2492.1913132596792663585.571870.76171[07/30/88]2908/09/8859560574105.9696.3910984287012393686.061820.671663208/12/8867430652806.7496.81122800100402342926.001790.591783608/16/88580105614.05.8096