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The physical and chemical characteristics of kimberlite Howe, Diane Joan 1997

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T H E PHYSICAL AND CHEMICAL CHARACTERISTICS OF KTMBERLITE FINES by DIANE JOAN HOWE B.Sc, University of British Columbia, 1980 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE in THE FACULTY OF GRADUATE STUDIES (Department of Mining and Mineral Process Engineering) We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA March, 1997 © Diane Joan Howe, 1997 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of ^ . ^ u , <. V \ , M : t A v . fte-ot^V.'^ . The University of British Columbia Vancouver, Canada Date C W . l 1 ^ \ DE-6 (2/88) ABSTRACT A detailed study of the physical and chemical characteristics of kimberlite fines provided the basis for this study which was to determine the factors that govern the flocculation processes. These studies showed that there are many physical and chemical characteristics which are similar and many which differ between the kimberlite samples. The mineralogical study showed that the type of minerals present were the same for each pipe, however their modal distribution varied. This difference is related to the type and intensity of alteration and the subsequent formation of clay-type minerals. The presence or absence of these alteration minerals also accounts for the differences found in the particle size distributions, in the surface areas, in the cation exchange capacities and densities. The zeta potential was found to be similar, with ranges between -15 to -35 mV, between the samples. Tests also showed the zeta potential could be further reduced by the addition of a Mg 2 + ion. This reduction in zeta potential did cause some of the pipes to coagulate and settle. Although no one variable could be found, flocculant preference of the individual kimberhte samples appears to be related to the interaction of particle and polymer as a function of solution chemistry. It is postulated that the dissolution of magnesium bearing minerals (olivine) play a significant role. The dissolution of olivine increases the concentration of Mg 2 + in solution thus promoting the attraction between particles and between the particle and polymer. In fact, chemical leach tests showed that Mg 2 + and Ca 2 + were readily leached into solution, albeit not all pipes leached these ions at the same rate. ii Values of up to pH 9.5 can be accounted for by the dissolution of olivine. Alkaline pH's >9.5 are assumed to be the result of the formation of calcium hydroxide after the magnesium ion precipitates out of solution as Mg(OH)2. Pipes which produce a very high pH therefore do not have the Mg 2 + ion readily available in solution to act as a coagulant. Goincidentally, these pipes required the addition of a coagulant to promote flocculation and a produce a clear supernatant. iii TABLE OF CONTENTS ABSTRACT ii TABLE OF CONTENTS iv LIST OF TABLES vii LIST OF FIGURES viii LIST OF PLATES x ACKNOWLEDGEMENTS xi 1.0 INTRODUCTION 1 1.1 OBJECTIVE OF STUDY 4 2.0 BACKGROUND 6 2.1 GEOLOGY AND FORMATION OF KIMBERLITES 6 2.1.1 Geology of the NWT kimberlite pipes 15 2.1.2 Weathering of kimberlites 18 2.1.3 The dissolution of olivine and resulting alkaline geochemistry 19 2.2 THE ELECTRIC DOUBLE LAYER AND SURFACE PROPERTIES OF KIMBERLITE SUSPENSIONS 21 2.2.1 The electric double layer 21 2.3 COAGULATION AND FLOCCULATION OF KIMBERLITE TAILINGS 28 iv 3.0 E X P E R I M E N T A L P R O C E D U R E S 35 3.1 SAMPLE PREPARATION 35 3.2 MINERALOGY 40 3.3 CHEMICAL LEACH TESTS 41 3.3.1 pH leach test 42 3.3.2 Olivine dissolution test 43 3.4 SURFACE PHYSICAL CHARACTERISTICS 45 3.4.1 Cation exchange capacity 45 3.4 2 Particle size, surface area and density 46 3.4.3 Surface electrical prop erties 46 3.5 FLOCCULATION TEST WORK 48 4.0 T E S T R E S U L T S •• 50 4.1 MINERALOGICAL ANALYSIS 50 1 4.2 CHEMICAL LEACH TESTS 63 4.2.1 pH leach test 6 3 4.2.2 Olivine dissolution test 71 4.3 SURFACE PHYSICAL CHARACTERISTICS 75 4.3.1 Cation exchange capacity 75 v 4.3.2 Particle size, surface area and density 78 4.3.3 Surface electrical properties 81 4.4 FLOCCULATION TEST WORK 85 5.0 CONCLUSIONS AND RECOMMENDATIONS 93 REFERENCES 100 APPENDIX A Mineralogical analysis 106 APPENDIX B Chemical leach tests 161 APPENDIX C Surface physical characteristics 168 APPENDIX D Flocculation test work 190 vi LIST OF TABLES Table 1: Geochemical composition of igneous rocks. 8 Table 2: Minerals found in kimberlite and lamproite..., 10 Table 3: General features of Panda, Fox, Misery, Koala and Leslie kimberlite pipes 16 Table 4: Kimberlite samples used in research 37 Table 5:.Mineralogy and modal distribution as percent from CIPW normative calculations for HPGR samples 59 Table 6: Mineralogy and modal distribution as percent from CIPW normative calculations for core samples 60 Table 7: Results of the pH leach test 64 Table 8: Mineralogy and modal distribution as percent from CIPW normative calculations for the pre and post-leach pH test 69 Table 9: Summary of the physical characteristics for each of the NWT kimberlite samples 77 Table 10: Cation exchange capacities (meq/lOOg) of common clay minerals 79 Table 11: Cation exchange capacities (meq/lOOg) of the NWT kimberlite samples 79 Table 12: Flocculation test work summary on the NWT kimberlites 87 vii LIST OF FIGURES Figure 1: BHP-Diamet, NWT Diamonds project location 2 Figure 2: Idealized kimberlite pipes -13 Figure 3: Acquisition of surface charge by metals in water 23 Figure 4: Solid particles immersed in water will accumulate an ionic cloud because of surface charge -24 Figure 5: The electric double layer 25 Figure 6: Effect of concentration and counter ion charge on zeta potential 26 Figure 7: The Derjaguin-Landau-Verwey-Overbeek theory 30 Figure 8: Polyacrylamide synthetic flocculants are based on polyacrylamide and its derivatives 31 Figure 9: Mechanism for particle bridging 33 Figure 10: Sample preparation schematic for the HPGR samples 38 Figure 11: Sample preparation schematic for the core samples 39 Figure 12: Ternary diagram showing the components of kimberlite and lamproite in terms of wt% K 2 0, MgO and A1203 51 Figure 13: Relationship between A1203 and Si02 in contaminated and contaminate free kimberlites 62 Figure 14: Bars on graph show the total metals leached for each of the NWT kimberlite pipes at various pH's in terms of mg/kg 65 Figure 15: Concentration of magnesium ions as a function ofpH 67 viii Figure 16: Concentration of calcium ions as a function ofpH ....68 Figure 17: Test results from the unwashed olivine sample showing changes in pH and Mg 2 + concentrations over 96 hours 72 Figure 18: Test results from the washed olivine sample showing changes in pH and Mg 2 + concentrations over 96 hours 72 Figure 19: Plot showing the average, maximum and nnnimum zeta potential values for all the HPGR samples in solution of 0.005 NaC104 82 Figure 20: Plot showing the average, maximum and minimum zeta potential values for all the core samples in solution of 0.005 NaC104 82 Figure 21: Plot showing the average, maximum and minimum zeta potential values for all the HPGR samples in a mixture of 0.005 NaC104 and 0.001 M Mg(C104)2 84 Figure 22: Plot showing the average, maximum and minimum zeta potential values for all the core samples in a mixture of 0.005 NaC104 and 0.001 M Mg(C104)2 84 Figure 23: Coagulation test on HPGR Misery 86 Figure 24: Flocculation test on HPGR samples using various concentrations of Percol E10 89 Figure 25: Flocculation test on HPGR samples using various concentrations of Percol 156 89 Figure 26: Flocculation test on core samples using various concentrations of Percol E10 90 Figure 27: Flocculation test on core samples using various concentrations of Percol 156 90 Figure 28: Flocculation test for Fox 1 using Percol E10 as a flocculant and Percol 368 as a coagulant 92 ix LIST OF PLATES Plate 1: Fluidized cell apparatus used for the olivine dissolution test 44 Plate 2: HPGR Misery sample under plain light 52 Plate 3: HPGR Fox sample under plain light 53 Plate 4: Core Misery sample under polarized light 54 Plate 5: Core Fox sample under polarized light 55 Plate 6: Leslie sample under plain light 57 Plate 7: Leslie sample under polarized light 58 Plate 8: SEM photo of olivine crystal showing attachment of fine particles 73 Plate 9: Close up view of Plate 8 showing attachment of fine particles 73 Plate 10: SEM photo of washed olivine crystals showing that most of the sub-fine particles have been removed 74 Plate 11: Close up view of plate 10 showing most of the sub-fine particles have been removed ..74 Plate 12: Olivine after 96 hours of leaching 76 Plate 13: Signs of minerals dissolution obvious in etching patterns 76 Plate 14: SEM photo showing particle size distribution for HPGR Leslie 80 Plate 15: SEM photo showing particle size distribution for HPGR Koala 80 Plate 16: Settling test on select kimberlite samples 83 Plate 17: Flocculation test for Fox 1 88 Plate 18: Flocculation test for Misery 1 using Percol E10 88 ACKNOWLEDGEMENTS I would like to acknowledge my advisor, Dr. G. Poling, and members of my supervisory committee, Mr. C Pelletier, Mr. M Rylatt and Dr. K Morin for their support and for giving me this opportunity. I gratefully acknowledge the funding support of Rescan Environmental Services Inc. (Mr. C. Pelletier) and BHP Diamonds Ltd whom provided funding for all the analytical work and financial support to the author. I would also like to thank the faculty, technical staff, fellow students and friends for the advice, laughs and good times. I would to thank Lenore for giving her time unconditionally. Most of all I would like to thank Berle for being there when I needed her and believing in me. x i 1.0 Introduction The discovery of diamonds in 1991 on the Canadian Slave craton has created the potential for the development of an entirely new rnining industry in Canada. The BHP-DiaMet Project (BHP), known as the "NWT Diamonds Project", is located in the Northwest Territories approximately 300 kilometers northeast of Yellowknife (Figure 1). The project is located in a remote region accessible only by airplane or winter road. It is north of the tree line and is characterized by numerous lakes, continuous permafrost, low relief, vegetation and wildlife typical of the tundra. Pending completion of feasibility studies and government approval diamond production will begin in late 1998. Based on the results of the ongoing bulk sampling programs, five diamond bearing kimberlite pipes (Panda, Misery, Koala, Fox and Leslie) are scheduled for development (NWT Diamonds Project, 1996). As in any new mine proposal, environmental considerations are integral components of development plans. With the development of five mines and the projected disposal of 133 million tonnes of mine tailings, the maintenance of water quality in this pristine environment is of prime concern. Kimberlite, a common host rock for diamonds, is a relatively soft rock and can be crushed easily to liberate the diamonds. The recovery of diamonds is relatively innocuous as the processing of the ore is mechanical and no potentially toxic chemicals are used. However, because it is a soft rock due to the weathering and alteration of the primary minerals, crushed kimberHte produces many fines. These fines, produced during clrilling, mining and the milling processes, form 1 Figure 1: BHP-Diamet, NWT Diamonds project location 2 suspensions that have been shown by BHP to be colloidally stable and highly persistent when deposited into an aqueous environment. This has resulted in high turbidity which presents problems in meeting discharge requirements (maximum allowable turbidity, 25 mg/L, Canadian Water Quality Guidelines) to the aqueous environment. Several techniques have been investigated by BHP in an attempt to improve the solid/liquid separation of the kimberUte suspensions. BHP has determined that commercially available flocculants added to a high rate clarifier/thickener gives the best results. These tests, however, show that not all the pipes could be treated with equal success using the same technique. One objective of this thesis was to determine why the NWT kimberlite suspensions react differently to the flocculation processes in terms of the type of flocculant used and dosages required to. produce a clear supernatant. This required an understanding of the physical and chemical properties of the particles and a basic understanding of the theories of surface chemistry and how they applied to the principles of coagulation and flocculation. This background information is presented in Chapter 2.0. The first step was to understand what a kimberUte is. A summary on lcimberUtes is given to provide an understanding into the diversity of the rocks we call kimberUte which can be mineralogicaUy, texturaUy and geneticaUy very different. Included is a review on the geology of the NWT lcimberUtes. KimberUtes also tend to have a unique aqueous geochemistry. This is discussed briefly through the mechanisms of olivine dissolution. FoUowing these discussions is a review on surface chemical principles and the uses of coagulants and flocculants and how they work. 3 The second part of this study was to perform mineralogical, chemical and surface physical tests on the kimberlite samples provided. The procedures and interpretation of these tests are presented in Chapters 3.0 (Procedures) and 4.0 (Results). These data allow for an assessment of how the theories of coagulation and flocculation compare to those experienced from actual, on-site data and laboratory test work. Conclusions and recommendations, which specifically discusses the lake deposition option for the NWT kimberhte tailings, is given in Chapter 5.0. 1.1 OBJECTIVE OF STUDY The overall objective of this thesis was to investigate the physical and chemical behavior of kimberHte fines and their interaction with the aqueous environment. This was done by completing the following specific studies: • investigate the bulk chemical and mineralogical components of the NWT kimberhtes using x-ray and petrographic techniques; • assess the physical and surface electrical properties of selected NWT kimberhte samples by determining the surface area, cation exchange capacity, particle size and zeta potential; and • for representative kimberhte samples, determine the best overall flocculant and dosage required to produce a clear supernatant. In addition, simple leach tests were conducted on select samples to obtain an understanding of how kimberHte fines behave when deposited in an aqueous environment. Two separate tests were conducted: • pH 'Modified swep" test; and • olivine dissolution test. This research was designed to develop a better understanding of the surface chemistry of the NWT kimberhte fines. Its intent was to provide information important to the selection of a flocculation technique to improve supernatant clarity and provide insight into the problems of chemical toxicity. 5 2.0 Background The NWT Diamonds Project proposes to mine and process five separate kimberlite pipes: Panda, Fox, Misery, Koala and Leslie. The processing of this ore is expected to produce 133 million tonnes of tailings. These tailings, if left untreated, produce colloidalry stable suspensions which respond poorly to conventional dewatering techniques. Current practice is to dispose of these fines in large impoundments to facilitate the settling of solids. However, if a suspension is allowed to stand quietly, the larger particles settle out first while smaller particles settle out more slowly, followed by a portion of very fine material which takes a long time or does not settle out at all. Resistance to settling by the very fine particles is the result of many factors, but all relate to the physical and surface characteristics of the particle including: mineralogy, size, density, surface area, surface charge and components in the aqueous medium such as pH and ionic strength. This chapter provides insight into these physical and surface characteristics and their role as applied to the theories of coagulation and flocculation. 2.1 G E O L O G Y A N D F O R M A T I O N O F K I M B E R L I T E S The main host rocks of diamonds at the surface are certain ultramafic, volcanic rocks, namely kimberlites. Kimberlite is a rare volcanic rock type that originates 150 km or more beneath the earth's surface. Diamonds form at similar depths and are found contained within kimberlite. From recent advances in age dating techniques, we know kimberlites are not genetically related to diamond formation, but that they merely serve as vehicles which transport diamonds from the upper mantle to the crust (Mitchell, 1991; Levinson et al., 1992; Helmstaedt, 1995; Helmstaedt and Gurney, 1995a, b). 6 Kimberlite is thought to form as a result of the partial melting of a carbonate enriched peridotitic rock (Kirkley et al., 1991). Peridotite is an ultramafic igneous rock and is one of the dominate rock types comprising the earth's mantle. Minerals found in peridotite are: magnesium-rich olivine (Mg2SiC>4), calcium-rich clinopyroxene (CaMgSi206) and magnesium-rich orthopyroxene (MgSi03). Other minerals such as magnetite, chromite, ilmentite and garnet are frequently associated with peridotites (Kirkley et al., 1991). Table 1 shows the geochemical composition of a felsic (diorite), mafic (gabbro), ultramafic (peridotite) and kimberhte magma. There has been a great deal of discussion in classifying kimberhtes (Clement and Reid, 1989; Mitchell, 1991; 1995; Skinner and Clement, 1979). It is difficult to define exactly what a kimberhte is because of its variable nature, which includes taking into account the mineralogical composition, chemical composition, texture, and origin. A current definition, abbreviated from Mitchell (1995) is as follows: "kimberhtes are a group of volatile rich (dominantly C0 2) potassic ultrabasic rocks which commonly exhibit inequigranular texture resulting from the presence of macrocrysts (in some cases megacrysts) set in a fine grained matrix. The mega/macrocryst assemblage consists of anhedral crystals of olivine, magnesium ilmenite, Cr-poor titanium pyrope, Cr-poor diopside, phlogopite, enstatite and Ti poor chromite. The matrix contains a second generation of olivine which occurs together with one or more of the following primary minerals; monticelhte, phlogopite, perovskite, spinel, apatite and serpentine." 7 T a b l e 1: G e o c h e m i c a l c o m p o s i t i o n o f i g n e o u s r o c k s ( % ) Oxide Diorite Gabbro Peridotite Kimberlite Si02 72.1 48.4 43.5 32.1 Ti0 2 0.04 1.3 0.8 2.0 A1 20 3 13.9 16.8 3.9 2.6 Fe 2 0 3 0.9 2.6 2.5 9.2 FeO 1.7 7.9 9.8 * MnO 0.1 0.2 0.2 0.2 MgO 0.5 8.1 34.0 28.5 CaO 1.3 11.1 3.5 8.2 Na 20 3.1 2.3 0.6 0.2 K 2 0 5.5 0.6 0.3 1.1 H 2 0 0.5 0.64 0.76 8.6 P2O5 0.2 0.24 0.05 1.1 co2 * * * 4.3 * no value given (Hurlbut and Klein, 1977; Bergman, 1987) As the kimberHtic magma ascends to surface, it will incorporate other mantle rocks (peridotite and eclogites) and lithospheric wall rock. The temperatures during ascent are not hot enough to completely assimilate these other rock types, thus the kimberlite magma will have within it foreign rock fragments or xenoliths. In some cases the rock itself may not survive the ascent to surface, but the individual mineral grains will be incorporated into the kimberlite magma 8 groundmass as xenocrysts. The mineralogical complexity of kimberlites comes from the fact that minerals contained within kimberhtes are derived from a number of different sources, such as: • primary kimberhte magma; • xenohths of upper mantle and lithospheric wall rock; • fragmentation of the upper mantle xenohths (peridotite and eclogitic rocks, including diamond) forming xenocryst or discrete nodule suite; and • alteration minerals formed during and after emplacement. . The contribution from each source varies widely which significantly influences the petrographic and geochemical character of the rock. A distinction cannot always be made between mineral phases that have crystallized from the kimberhte magma (phenocrysts) and those that have been derived from the fragmented lower-crustal or upper-mantle xenohths (xenocrysts). Coupled with this extensive mineralogical variation is considerable textural diversity between and within the kimberhte pipes. All have a distinctive inequigranular texture resulting from the presence of macrocrysts and phenocrysts sitting in a fine-grained groundmass in proportions as varied as their emplacement mechanisms. Kimberhtes are classified on the basis of their groundmass mineralogy (Skinner and Clement, 1979). Table 2 shows minerals typically found within a kimberhte pipe. Also included are minerals found in lamproites, another source for diamonds, which are not part of this discussion. 9 Table 2: Minerals found in kimberlite and lamproite Mineral Kimberlite Lamproite Kimberlite Magma Olivine / Diopside Phlogopite Calcite Serpentine Monticellite Leucite Amphibole </ Enstatite Sanidine </ Minor minerals Apatite Perovskite JJmenite Spinel Priderite Nepheline </ Wadeite •/ Upper Mantle Olivine Garnet Clinopyroxene •/ Orthopyroxene Chromite S Diamond (Kirkley et al, 1991) 10 Minerals belonging to the xenocryst group are the minerals most often used as indicator minerals in the search for kimberhtes. Although they may not have a genetic relationship to kimberhte, and are foreign grains incorporated by the kimberhte, they are indicative of material derived from the upper mantle where diamonds may have formed. Kimberhte eruptions are gas charged, and therefore rise in a rapid and explosive manner. It is generally accepted the rate of ascent must be reasonably rapid because diamonds and diamond bearing xenohths transported from as deep as 200 km below the surface, are found in kimberhtes (Kirkley et al., 1991). Reported estimates on kimberhtes rate of ascent vary from 10-30 km per hour to within 2-3 km of the surface where the velocity is dramatically increased to several hundred kilometers per hour as they break explosively through to the surface (Eggler, 1989; Kirkley et al., 1991). Should a magmatic explosion result, they are of relatively short duration and involve small volumes of magma (Mitchell, 1991). In general, kimberhtes tend to have a circular, ellipsoidal or kidney shaped expression when viewed in plan. They tend to occur as small volcanic diatremes and pipes which taper with depth and are often described as carrot shaped (Mitchell, 1991). The size, shape, depth and complexity of a kimberhte pipe varies considerably. The depth of groundwater at the time of eruption and its availability are important phreatomagmatic variables that account for the shape and volume of the deposit (Nixon, 1995). The pipe or diatreme is reamed out when an expanding mix of gas and magma sohds breaks through to the surface. This gas charged explosion will throw rock fragments and mineral grains, including diamonds, out of the pipe. The rest of the material left in the pipe is cemented together by the crystallized residual gaseous products such as calcite (CaO + CO2) and serpentine (MgO + Si02 + H20). Eruptions 11 can terminate with little or no diatreme development after a single eruption, or multiple eruptions may result due to successive ejections of steam and water (Nixon, 1995). A kimberlite volcano includes: a feeder magmatic dike intrusion or hypabyssal root zone, a diatreme — comprised predominately of breccia, and the overlying crater zone with epiclastic (reworked) sediments and an apron of pyroclastic ejecta (flows, falls, surges). Rocks belonging to each facies differ in their petrography, rnineralogy, and texture. An idealized kimberlite volcano and magmatic system is illustrated in Figure 2. Root Zone Composed of crystallized kimberlite magma, the root zone is the deepest part of the pipe, located at about 2-3 km below the surface. It is irregular in shape, varies in widths between 0.6 and 10 metres and may extend over 500 metres in length. With depth, the root zone grades into individual feeder dikes extending downward indefinitely but not continuously (Kirkley et al., 1991). The intrusions in root zones consist mainly of hypabyssal-facies kimberUtes and kimberlite breccias. Although these intrusions exhibit extensive petrographic diversity, they all reflect the emplacement of 'normal' kimberlite magma (Skinner and Clement, 1979). A relatively slow crystallization of root zone intrusions is indicated by the hypabyssal nature of the intrusions (Clement and Reid, 1989). 12 EPICLASTICS Figure 2: Idealized kimberlite pipe (Mitchell, 1991) 13 Diatreme The diatreme represents a much greater vertical extension than does the root zone, ranging from 1 to 2 km in height extending to within 300 metres of the surface. It is typically regularly shaped (inverted truncated cone), and has steep, joint-bounded generally smooth or striated contacts and vertical axes (Clement and Reid, 1989). The main characteristics of the diatreme zone are the volcanoclastic breccias, tuff and other fragmented rocks resulting from the forceful, explosive injection of the magma. Contained within these pyroclastic rocks are xenoliths and xenocrysts from the mantle and other crustal rocks which have been incorporated into the magma during its rise. In terms of mining, the diatreme is the most important source of diamonds because of its volume. Crater Zone The crater zone is that part of the kimberlite which shares typical features with a volcano in terms of the types of rocks found. Craters tend to form shallow basins <500 meters in depth and, have relatively flat slopes, brecciated contacts and a tendency towards circular shapes (Clement and Reid, 1989). Unlike other volcanoes which erupt magma, the crater zone of a kimberlite erupts as solid, broken fragments of rock. This is because by the time the kimberlite has passed through the diatreme it is no longer molten. Little is known about the broken rock fragments (pyroclastics) which land outside the crater (tuff ring) because of their scarcity due to erosion. Within the crater, both pyroclastic rocks and rocks derived by the erosion of the pyroclastic rocks are re-deposited back into the crater. These deposits typically form bedded or graded deposits. 14 2.1.1 Geology of the NWT kimberlite pipes The NWT diamond bearing kimberhte deposits are located in the Slave Geological Province of the Canadian Shield. The Slave Province contains the earth's oldest rocks (3.96 Ga.) and is comprised of several discreet terrains, including from east to west: a core area of metamorphosed intrusive rock namely granodiorites and quartz diorites, a band of gneisses and migmatites and a large greenstone belt. It is within the greenstone belt that the NWT kimberhtes are found. Rocks found on the property include metasedimentary schists and migmatites and various syn- and post-tectonic intrusives. Age dates of the kimberhte (0.052 Ga.) show that diamond bearing intrusives are significantly younger than their host rocks (1.27-1.67 Ga.) (NWT Diamonds Project, 1996). Geologically speaking, the NWT kimberhtes are similar to the South African and Russian occurrences in that the hypabyssal mineralogy is similar. One major difference is that some of the NWT kimberhte crater zones are intact, and the olivine rich kimberhte may contain more country rock fragments. A generalized textural pattern can be inferred as the pipes show a gradation from a fine grained to coarse grained texture with increasing olivine at depth. Table 3 outlines the general features of each pipe. Each pipe exhibits a wide range of characteristics in terms of mineralogy and textures. Panda Pipe The Panda pipe, host within a weakly fohated massive biotite granite is described as a diatreme with both volcanoclastic and sedimentary hthologies present. These rocks are juxtaposed in a chaotic fashion suggesting episodic eruptive events formed the Panda diatreme. 15 Table 3: General features of Panda, Fox, Misery, Koala and Leslie kimberlite pipes Pipe Dimensions Depth of Overburden Surface Feature Depth of Crater Type * Panda 150x150 m 19 m diatreme n/a TK, TKB and epiclastic rocks Fox 225x400 m 25 m crater 130-180 m epiclastic, TK, TKB Koala 200x200 m 35 m crater 96-120 m TK, TKB Misery 100x150 m 12 m diatreme n/a TK, TKB Leslie 295x295 m 8m hypabyssal n/a hypabyssal * TK= tuffisitic kimberlite, TKB= tuffisitic kimberlite breccia (NWT Diamonds Project, Feasibility Study, 1996) Rock types identified include a fine to coarse grained tuffisitic kimberlite and tuffisitic kimberlite breccia mixed with isolated discrete lenses or blocks of mudstone, siltstone and sandstone. Fox Pipe The Fox pipe consists of a 130-180 metre crater zone overlying a diatreme. The crater zone which exhibits minor bedding features consists of a black fine grained Idmberlite with xenoliths of mudstone. The kimberlite is comprised of olivine macrocrysts (or serpentine, talc and/or calcite) within a phlogopite dominated groundmass which also contains olivine, serpentine, and calcite. 16 The upper part of the diatreme zone is mineralogically similar to the crater zone, however, quartz, feldspar and biotite have also been observed in the diatreme. Clay often replaces the feldspar mineral. A thick granitic boulder zone crosscuts the entire pipe and separates the upper part of the diatreme from the lower. Below the granitic boulder zone, in the lower half of the diatreme, serpentine replaces phlogopite as the dominate groundmass constituent and the olivine tends to increase and coarsen with depth. The Fox pipe contains more country rock than any of the other pipes. Unlike the other pipes, it is speculated the Fox kimberlite forced its way along a highly fractured, faulted, host rock structure, thus easily incorporating foreign host rock. Koala Pipe The host rock for the Koala pipe is a biotite granite, however, a variety of other rock types have been observed in close proximity and include granodiorite, granite gneiss, and diorite. A well bedded, 150 metre deep crater zone overlying a diatreme has been identified. The crater shows distinctive bedding features, grading from silty, sandy layers to a coarse grained tuffaceous Idmberlite breccia at depth. Interlayered are zones of fine grained mudstones. The discrete layering described above is thought to represent three distinctive eruptive events separated by quiescent lake sedimentation. Minerals identified include quartz, mica, olivine, talc, chlorite and minor pyrite in the upper zones, with an increase in olivine, serpentine, phlogopite, vermicuhte, calcite, garnet and diopside with depth. The diatreme zone is comprised of a matrix of olivine and serpentine with macrocrysts of serpentine, garnet and diopside with xenoliths of granodiorite, mudstone, sandstone and eclogite. 17 c Misery Pipe Two pipes are located at Misery, a north and south pipe. The north pipe, the pipe of interest, is found at the contact between a foliated biotite schist and granite. The granite, described as a two mica granite, contains abundant primary muscovite. The Misery diatreme is approximately 400 metres thick and is comprised of a mix of pyroclastic and volcanoclastic units. Numerous xenohths rich in serpentine macrocrysts suggest pre-alteration events. The diatreme has been reworked as indicated by fining and sorting textures. Multiple phases of eruption are interpreted for the Misery diatreme. Hypabasal dikes, consisting of coarse grained olivine, garnets and diopside in an aphanitic phlogopite clay mixture cross cut the area. These dikes are thought to represent the early stages of pipe development. Leslie Pipe The Leshe pipe, hosted within the same weakly fohated massive biotite granite as Panda, is generally fresh, competent and is described as hypabyssal in origin of a single phase. It is comprised of megacrysts of olivine, rare phlogopite, garnet and diopside within an olivine, chlorite, serpentine groundmass. The groundmass contains minor calcite, ilmenite and pevoskite. Rare xenohths of granite, dunite and mafic rock are also described by BHP. 2.1.2 Weathering of kimberhtes Kimberhtes are likely to be much more deeply weathered than the surrounding host rock because of their high porosity and ultramafic mineral assemblage (Berg, 1989; Macnae, 1995; Zinchuk, 1982; Zinchuk, 1992). However, even before the kimberhte mineral assemblage reaches 18 the surface, the magma may undergo deuteric and metasomatic alteration. These alteration processes occur during the late stages of magma consolidation. Other reactions such as serpentinization, carbonatization, chloritization may occur during and after pipe emplacement (Hodgson et al., 1988). There are some 70 secondary mineral products of Idmberlite formed during alteration and weathering, including the more common calcite, dolomite, chlorite, talc, micas and quartz (Hodgson and Dudeney, 1988). The formation of serpentine from olivine (serpentinization) is the most common form of alteration (Moody, 1976). 2Mg2Si04 + 3H20 => Mg3Si205(OH)4 + Mg(OH)2 (olivine + water =>' serpentine + brucite) The factors which determine which secondary minerals form are the variations in the chemical potentials of C0 2 and H 2 0 (Mitchell, 1995; Milashev, 1963). Carbonatization generally follows serpentinization. For example, depending on conditions, serpentine will further alter to talc, biotite, illite, kaolinite and montmorillonite with carbonate or quartz (Hodgson and Dudeney, 1988; Milashev, 1963). Depending of the degree and intensity of the weathering processes, clay minerals represent the final stages of the weathering process (Macnae, 1995). 2.1.3 The dissolution of olivine and resulting alkaline geochemistry Waters draining ultramafic rocks tend to have unusual characteristics including: very high pHs (between 11 and 12), a low concentration of carbonate species, and low concentrations of magnesium and silica. These waters were essentially found to be dilute solutions of calcium hydroxide (Barnes et al., 1967; 1978; 1971; Hem, 1992). Since kimberlite is similar in mineral 19 composition to an ultramafic rock, it stands to reason these waters can be derived by the dissociation of magnesium-calcium bearing kimberhte minerals as well —olivine being the primary mineral component. The dissolution rates for olivine are among the highest rates measured for common silicates (Wogehus and Walther, 1992). The dissolution of olivine is as follows: Mg2Si04(forsterite) + 2H20 = 2Mg2 + + 20FT + H2Si04(aq) Olivine is known for its acid neutralizing capacity and its potential to neutralize acid mine waters (Van Herk and Pietersen, 1989; Schuiling et al., 1986). With the dissolution of olivine the pH is driven up as the H* ion is consumed. This causes the precipitation of calcium and magnesium carbonates until all carbonate species initially present in solution are removed as sohds, and free hydroxyl builds up in solution. The solution becomes supersaturated with respect to brucite and serpentine and these minerals precipitate, Mg 2 ++ 20FT = Mg(OH)2 (Brucite) 3Mg2 + + 60FT + 2Si02 ( a q ) = Mg3Si205(OH)4 (Serpentine) + H 2 0 The precipitation of brucite and serpentine keeps the concentrations of magnesium and silica at low values. Hydroxides and silicates of calcium are more soluble than their magnesium equivalents thus the small amounts of calcium not precipitated as carbonate, are left as the major cation in solution thus forming dilute solutions of CaOH (Drever, 1982). 20 2.2 T H E E L E C T R I C D O U B L E L A Y E R A N D S U R F A C E P R O P E R T I E S O F K I M B E R L I T E SUSPENSIONS To enhance the separation of kimberhte suspensions, commerciaUy available coagulants and flocculants are used in order to produce a clear, particle free effluent. This section reviews the surface chemical and electrical principals which govern the coagulation and flocculation processes. 2.2.1 The electric double layer All particles suspended in a homogeneous polar liquid (such as water) acquire an electrical surface charge. This charge originates from several possible mechanisms. For example: • particle ionization in the case of ionic sohds; • particle adsorption of ions from the hquid; or • excess dilution of ions of one sign charge, as in the case of oxides and clays. In kimberhte suspensions, silicates are the major mineral constituents with the most predominate being olivine, (Mg2Si04), and various phyllosilicate (clay) components. Olivine will take on a net negative charge when suspended in water. This results when the broken bond structures on the olivine silicon tetrahedron bind to water molecules to form hydrated Si04. In alkaline solutions the hydrated Si04 will lose an FT yielding a negatively charged particle and under acidic conditions, the molecule will gain an FT yielding a positive charge. Broken bond structures found on the edge of clay particles react similarly in aqueous solution. It is important to note that these edge charges will be affected by the pH of the solution (Figure 3). 21 Clays are unique in that they may exhibit two types of charges; a negative edge charge which can be changed with pFL and a positive face charge which is permanent. The positive charge originates from cation substitutions in the mineral and cannot be changed by pH. Due to this surface charge, a sohd particle immersed in water will accumulate an ionic cloud or electric double layer (Figure 4). This electric double layer results when oppositely charged ions in the liquid are attracted to charges on the surface of the particles. The ions closest to the particle (stern layer) are strongly attached and will travel with the particle if it moves in liquid. The more diffuse ions (diffuse layer) will stay with the liquid. The plane of separation is called the surface of shear and an electrical potential called zeta potential (£) is measured at this surface (Figure 5). Since the zeta potential can be determined more easily than the actual surface charge, it is often taken to be a convenient measure of that charge. In terms of the ions in solution, it is the charge at the zeta potential which governs their response. The magnitude of the zeta potential is often in the order of tens of millivolts and depends upon: the surface charge on the particle (surface potential), the concentration of the counter ions, and the charge carried by the counter ions (Figure 6). A practical way to measure zeta potential as a characteristic of the double layer is to shear off the diffuse layer and measure the potential that was created or apphed by measuring the velocity 22 Mn—O—Mn—O I I 0 O 1 I O—Mn—O—Mn I I 0 O 1 I Mn—O—Mn—O I I 0 O 1 I O—Mn—O—Mn I O H hydration + H ,0 H 0 O H -1 I " HO—Mn—O—Mn—O I I 0 o 1 I O — M n — O — M n — O H ' "HO—Mn—O—Mn—O I I 0 o 1 I O—Mn—O—Mn—OH" I I O H " O III H H \ / 0 O \ I I O—Mn—O—Mn—O H O O , 1 I / O—Mn—O—Mn—O I I \ 0 O * \ I I O—Mn—O—Mn—O H O O L 1 I / O—Mn—O—Mn—O I I ^ 0 b , 1 I / *HO—Mn—O—Mn—O H O O 1 \ I I O—Mn—O—Mn—OH* ' I I 0 O v 1 I / *HO—Mn—O—Mn—O A- ^ I H . H O / \ H H IV O a l n m , .^^ 5^ 1 b y c o U o i d a l Mn°2 " Anhydrous MnO, 0) has two VfeSf^ tf? ™ 3w "L*??3^ a c o U o i d - it binds to water molecules to form hydrated i ^ ^ l f 5 5 oH . ^ ^ b o u n d H 2 ° yield* a negatively charged colloidal particle (Dfj. Gain, ^ " p r e d ^ S c ? S ! ? t e .^'UVely *"* P a r t i C ' e ( I V ) - ^ f o r m e r ^ Cos. of H+ Figure 3: Acquisition of surface charge by metals in water (Manahan, 1991) 23 Figure 4: Solid particles immersed in water will accumulate an ionic cloud because of surface charge (Manahan, 1991) 24 Figure 5: The electric double layer. Zeta potential is located at the surface of shear between the bound layer and the diffuse layer (Shaw, 1966) 25 100* KX)X Figure 6: Effect of: a)concentration of univalent electrolyte, andb) counter ion charge zeta potential (Shaw, 1966) 26 of particle travel. There are several techniques used to measure zeta potential. The best known is electrophoresis — the migration of small particles suspended in a polar liquid subject to an electric field. The particles tend toward an electrode of opposite charge. The particles, regardless of their size and shape, move at the same velocity (electrophoretic mobility). This mobility can be easily measured so the zeta potential can be calculated: \ =13v£ v = electrophoretic mobility, E = applied potential (volts/cm) In order to induce particle aggregation, the zeta potential must be reduced to ensure that Van der Waals attractive forces can predominate. The zeta potential can be reduced by either: adjusting pH, increasing the ionic strength of the suspending medium, or by increasing the adsorption of counter ions. Detailed studies on the zeta potential of kimberhte by Mackenzie and Lovell (1971, 1972), and O'Gorman and Kitchener (1974), show kimberhte fines have a high zeta potential of-77 mV. This would account for the high stability exhibited by kimberhte suspensions. From this work, it was also shown the zeta potential can be depressed by adjustments in pH, or by the addition of multivalent metal cations (Ca2+ or Mg2+). The lowering of pH was not found to be a practical application because a very low pH< 3.0 is required for coagulation to occur. The adsorption of multivalent metal cations caused kimberhte to coagulate by reducing the net surface charge on the particle. These cations are referred to as specifically adsorbing ions (SAT) and are highly surface dependent, probably because of the high surface activity of the metal hydroxyl cations (O'Gorman and Kitchener, 1974). Magnesium has been shown to be superior to calcium in reducing zeta 27 potential. This may result because magnesium is a major lattice ion present in many kimberhte minerals and is adsorbed more strongly by chemical bonding mechanisms (O'Gorman and Kitchener, 1974). 2.3 C O A G U L A T I O N A N D F L O C C U L A T I O N O F K I M B E R L I T E T A I L I N G S Coagulants and flocculants serve primarily to improve sedimentation rates or increase clarification of effluent waste waters. They are often misused or considered interchangeable because both processes lead to an increase in particle size thus giving higher settling rates. There is, however, a difference in the two processes. In accordance with current usage, the term coagulation is used to describe aggregation resulting from the addition of charge reducing reagents to reduce electrostatic repulsion and induce Van der Waals attraction between particles The term flocculation is used to describe the aggregation produced by the bridging action of polymer reagents between particles. Coagulation is a process which brings particles into contact by lowering the energy barrier so that Van der Waals attraction forces can act to form agglomerates (coagules) which settle easily. Some coagulants simply neutralize the surface charges on the primary particles, others suppress or thin the electric double layer (indifferent electrolytes), and some even combine with the particles through hydrogen bridging or complex formation. The Derjaguin-Landau-Verwey-Overbeek (DLVO) theory explains why particles can be coagulated by decreasing the electrical repulsive forces between the particles. The theory involves 28 the estimation of energy due to the overlap of the electric double layer and the Van der Waals energy in terms of interparticle distance. Coagulation will result when the electrostatic energy barrier of curve S (see Figure 7) is minimized. Flocculation uses chemical polymers, usually in the form of natural or synthetic polyelectrolytes. For mining apphcations, polyacrylamide flocculants (PAMs) of high molecular weight (106) are used. Figure 8 shows a pure polyacrylamide and some of its derivatives. Polyacrylamide is essentially non-ionic. The co-polymerisation of polyacrylamide with other molecules gives an ionic character to the flocculant. The ionic character, either a positive (cationic) or negative (anionic) charge, serves two primary functions: • provide a means of adsorption onto the particle surface by electrostatic attraction; and • cause the polymer molecules to extend and uncoil due to charge repulsion along the length of the polymer chain so that the molecule is linear and can bridge to more particles. The most commonly used type of synthetic polymer used in mining apphcations is the anionic polyacrylamide. This polymer which has some of the amide groups along the chain replaced by carboxyl groups. These form poly-sodium carboxylate salts in the solution state. In neutral to higher pH water solutions, these anionic polyacrylamids have a net negative charge. To determine 29 Figure 7: The Derjaguin-Landau-Verwey-Overbeek theory. Curve A shows the attraction forces; curve R shows the repulsion forces; curve S is the summation of curves A and R and is the actual potential energy curve followed by two particles approaching one another (Moss and Dymond, 1987) 30 Anionic polyelectrolytes Catiohic polyelectrolytes H H — C — C — polyvinyl pyridinium H H H I I I — C — C — N — | I I I H H H polyethylene imine polystyrene sulfonate Nonionic polymers H I H I - C C -I I cor H polyacrylate H H I I — C — C — I I 0 H 1 H polyvinyl alcohol H H I I — C — C — I H C — N H 2 II O polyacrylamide Figure 8: Polyacrylamide synthetic flocculants are based on polyacrylamide and its derivatives (Manahan, 1991) 31 the best flocculant it is necessary to find out which degree of carboxylation does the best job for enhancing or settling of a certain particulate phase. As an example, kaolinite, a common clay constituent, is best flocculated by 30-35% carboxylated polyacrylamide (O'Gorman and Kitchener, 1974). The molecular mechanism for flocculation is postulated to be the formation of bridges between mineral particles which lead to larger aggregates that settle rapidly (Figure 9). The best bridging is obtained when the polymer is only just adequately attached, leaving long loops in solution available for further bridging. The best bridging flocculants are the anionic flocculants because they tend to be of a higher molecular weight than cationics (Hab/erson, 1987). It would be expected that since most suspensions encountered in the mining industry contain negatively charged particles, cationic polyelectrolytes would be best suited. However, in the case of bridging flocculants, the polymer need only be adequately attached. There are many factors affecting flocculation. Often times it is a trial and error process to select a flocculant best suited to the application. For example, for sedimentation, a small, dense floe is best, whereas for filtration, an open floe is better. Some of the factors to consider include: solution pH, particle size, pulp density of feed, molecular weight of polymer, charge density of polymer, mixing technique and temperature (Moss and Dymond, 1987). Kimberlite, being a relatively unknown material, has had little documented research done on the use of flocculants and coagulants in the dewatering of its suspensions. Other than this research 32 Figure 9: Mechanism for particle bridging. The theory assumes that the polymer attaches at several points leaving loops projecting which attach to other particles (Moss and Dymond, 1987) 33 (UBC) and work done by the company (BHP), the only other research found was that of MacKenzie and Lovell (1971, 1972) and O'Gorman and Kitchener (1974). Their coagulation and flocculation test results showed: • an inorganic coagulant was successfully used to reduce electrostatic repulsion and promote coagulation— MgS04 gave the best results; • dosages were much higher than expected due to the very high specific surface area of the colloidal fraction; • the best combination of coagulant and flocculant was the addition of a critical amount of MgS0 4 to induce coagulation followed by the addition of an anionic flocculant; • floe strength could be controlled by dosage of the anionic flocculant. Their work showed that kimberhte fines behaved like any other better known colloidal clays (montmorillonite, kaolinite) with respect to electrical double layer properties. 34 3.0 EXPERIMENTAL PROCEDURES This chapter reviews the experimental procedures used for this research. Section 3.1 discusses the sample preparation techniques. Two samples sets were used for this research; one sample set was pre-crushed using a high pressure grinding roller (HPGR), and the other sample set was received as core pieces. The objective of these preparations was to liberate the fine (-75 um) particles to be used in this test work. In section 3.2, the procedures used to determine the mineralogy of the NWT kimberlite pipes is reviewed. Petrographic techniques were used to determine the primary mineral components and x-ray techniques were used to determine the bulk chemical compositions. The pipes were compared in terms of normative mineralogical calculations. Following mineralogy, the test procedures used to identify the chemical leaching characteristics are presented in Section 3.3 The first procedure was a pH leach test, which resembles a modified special waste extraction (SWEP) test. This is followed by an olivine dissolution test, which was designed to look at the effects olivine dissolution has on solution pH. Section 3.4 outlines the procedures used to identify the physical characteristics of the kimberlite fines. These include: cation exchange capacity (CEC) particle size, surface area, density and surface charge (zeta potential). Finally, Section 3.5 outlines the flocculation and coagulation testing done on select Idmberlite samples. 3.1 SAMPLE PREPARATION A total of 17 samples representing five Idmberlite pipes Panda, Fox, Misery, Koala and Leslie were tested (Table 4). The 17 samples have been split into two groups and consist of five HPGR 35 samples supplied from the BHP pilot process plant in Reno, and twelve core samples supplied by BHP in Kelowna. Figures 10 and 11 outline the sample preparation procedure for both sample sets. The HPGR samples were crushed using a high pressure roller grinding process prior to being received for this research. These samples were used because they best simulate the conditions that will be used in processing the kimberhte. However, there is some concern that these samples may not be truly representative. These samples were actually the coarse fraction of another sample set in which the true fines were removed prior to being crushed. For this study, no further size reduction was conducted on these samples except in the preparation of the X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD) samples. The core samples from Kelowna were received as NQ size core pieces. The core was size reduced at UBC's, Mining and Mineral Processing labs using a cone crusher and disc pulverizer with the intent of liberating fine mineral particles. All samples were screened to a coarse (+100 um), medium (-100+75 um) and fine (-75 um) fraction using a Ro-Tap vibrating screen shaker. Sample preparation was performed dry to prevent mineral dissolution. AU test work conducted utilized the -75 um fraction or less with the exception of the thin section analysis and leach tests. Samples were split for the various tests using a Jones riffle sampler. 36 Table 4: Kimberlite samples used in research Sample Type Hole Depth (m) Lithology Pipe zone HPGR Panda Roller crushed HPGR Fox Roller crushed HPGR Misery Roller crushed HPGR Koala Roller crushed HPGR Leslie Roller crushed Panda 1 Core PUC 2-4 9.14-13.7 TKB Crater Panda 2 Core PUC 2-4 20.7-25.6 TKB Crater Panda 3 Core PUC 2-4 25.6-38.1 TK Diatreme Panda 4 Core PUC 2-4 65.3-70.4 TKB Diatreme Fox 1 Core FUC 4-9 31-31.4 TKB Diatreme Fox 2 Core FUC 4-6 64-64.7 TKB Diatreme Fox 3 Core FUC 92-1 45.7-106.7 TK Diatreme Misery 1 Core MCH3 304-306.9 TK Diatreme Misery 2 Core MCH3 332-335 TKB Diatreme Koala 1 Core 92-10 157-178 TK Diatreme Koala 2 Core 92-10 332-335 TK Diatreme Leslie 1 Core LDC 13 68.6 KB Hypabasal TKB=tuffisitic kimberlite breccia TK=tuffisitic kimberlite KB=kimberlite breccia 37 HPGR SAMPLE sample split + Imm OLIVINE DISSOLUTION TES T Imm screen d • o v v • Imm par t ic le s ize thin section pH L E A C H T E S T v m pulverize (-75 micron) r X R F L XRD Infrasizer (air sort) coarse <-(+ 75 micron) (retoin) I X R F XRD SEM - porticle size BET - surfoce oreo CEC - cation exchange ZETA potential V V fines (- 75 micron ] flocculation / coagulation (optimization and turbidity) Figure 10: Sample preparation schematic for the HPGR samples 38 CORE SAMPLE \) ) crush 8 mm ~> hond sample sample split W pulverize screen 75 micron w * thin section -> flocculation/coagulation testwork -> XRF XRD SEM - particle size BET - surface area ZETA potential Figure 11: Sample preparation schematic for core samples 39 3.2 M INERALOGY The mineral assemblage of each kimberhte sample has been determined using petrographic (hand and thin section descriptions) and XRD techniques. Whole rock geochemistry was determined by XRF techniques. In preparation for thin sectioning, the core samples were crushed to approximately +4 mm. The HPGR samples were used as received. AU samples were fixed in an epoxy and sectioned using oil to prevent mineral dissolution. X-Ray diffraction is a determinative tool used to identify minerals within completely unknown substances. Advantages of XRD are that it is nondestructive and can be done within a short time on a very smaU volume of sample. The minerals within each kimberhte sample were identified using the Siemens D5000 X-Ray Diffractometer and the D5000 mineral search program housed at UBC's Earth and Ocean Sciences Department. Unknown minerals were identified using a match with ASTM (American Society for Testing Materials) mineral standards. Samples for XRD were prepared by grinding the sample to approximately -38 um with a mortar and pestle. The sample was then smear mounted on a standard thin section of glass. For the HPGR samples, spectra were collected from 3-60° 20 using a step size of 0.02° 29 with a counting time of 1 second per step. For the core samples, spectra were collected from 3-30° 20. The minerals identified represent the major minerals present within the sample — minerals with less than 3% distribution could not be identified. 40 X-Ray fluorescence spectroscopy was chosen as the method to analyze elements within each Idmberlite sample. XRF is an established tool for chemical analysis and is well suited for bulk chemical analysis. All 17 samples (-38 um) were submitted to Geochemical Laboratories, Earth and Planetary Sciences, McGill University for whole rock analysis. Elements are reported in the form of percentage oxides. This laboratory uses a Philips PW2400 3kW automated XRF spectrometer system The major elements (Si, Ti, Al, Mn, Mg, Ca, Na, K, and P) and trace elements (Ba, Cr, Cu, Ni, V) were analyzed using a 32 mm diameter fused bead prepared from a 1:5 (sample:hthium tetraborate) mixture. The oxide analysis was used to complete CIPW normative calculations using the computer based program NewPet (Memorial University, 1994). 3.3 CHEMICAL LEACH TESTS Two separate chemical leach tests were performed on select kimberhte samples: • pH leach test; and • olivine dissolution test. The pH leach test was conducted in order to obtain a better understanding of how the kimberhte tailings would react when deposited into an aqueous environment. The olivine dissolution experiment was performed to test the hypotheses that the mineral olivine dissociates under standard aqueous conditions to produce an alkaline pH. 41 3.3. J pH leach test A pH leach test was conducted to determine the relative quantities of metals that a kimberhte material may release when deposited in an aqueous environment. A modified SWEP procedure was used — solids from each of the HPGR samples were agitated for 24 hours in pH solutions of 7, 9, and 11. These solutions were chosen to simulate the conditions of tailings deposition observed during the on-site test work. Whole rock analysis was performed before and after on each sample to determine elemental changes. A 5 kg sample was obtained using a Jones riffle from each of the five HPGR samples. From each 5 kg sample, three 1 kg samples were split. Whole rock chemical analysis and particle size screening was conducted on each sample prior to testing. Samples were subjected to a 24 hour leach in pH solutions of 7, 9, and 11. Each 1 kg sample was placed into a 2000 mL erlymer flask, with 1 htre of distilled water added and brought to the desired pH. Samples were agitated using mechanical stirrers, and monitored over a 24 hour period. The pH was adjusted, when required, using NaOH or HC1. At the end of the 24 hour period, a 250 mL portion of each sample leachate was filtered into an acid rinsed bottle and sent to Elemental Research in North Vancouver for analysis of Al, Ca, Mg, K, Fe, and Si. The remainder of the sample was pressure filtered, oven dried and weighed. Samples were then pulverized, screened (-38 um) and a spht sample was sent for XRF whole rock analysis. 42 3.3.2 Olivine dissolution test It is postulated the alkaline waters experienced when processing kimberhte is due to the dissolution of ohvine and that the dissolution is promoted by the crashing and grinding of the mineral into sub-fine particles. The olivine dissolution test was designed to observe these effects. This experiment is based on a fluidized bed, continuous reactor technique developed to study the kinetics of weathering feldspars (Chow and Wollast, 1984). In a fluidized bed reactor, the flow of fluid is adjusted so that its velocity equals the settling rate of the particles such that a homogeneous suspension is achieved where the solid and fluid are extensively mixed. The advantages of this type of reactor are that there are no chemical gradients and that the solution is kept undersaturated so that no precipitates are generated. Short term dissolution tests were run on crystals of olivine hand-picked from the Panda HPGR sample. The grains were tested for purity using XRD. The olivine was dry ground using a hand mortar and sieved to obtain a size fraction between 75 - 100 um. Prior to the dissolution experiments, the sample was split and one sample set was ultrasonically washed of fine adhered particles using distilled water and acetone until a clear supernatant was observed. A scanning electron microscope (SEM) was used to monitor sub-fine particle adherence. Tests were run over a 96 hr period (4 days). In the fluidized bed reactor, 150 mL of distilled water was combined with 10 gm of olivine (Plate 1). Over the 96 hour period, leachate samples were collected and analyzed for pH and magnesium For the first 12 hours, 10 mL of sample was collected in acid rinsed bottles 43 Plate 1: Fluidized cell apparatus used for the olivine dissolution test 44 every 3 hours, then once every 12 hours for the duration. In order to maintain a small difference in concentration of the overall solution, it was necessary to keep the sample extraction small (5% of total volume), so that the renewal rate integrated easily and did not affect the concentration. For every 10 mL extracted, 10 mL of laboratory distilled water was added. 3.4 S U R F A C E P H Y S I C A L C H A R A C T E R I S T I C S Procedures for deterrnining physical and surface electrical properties are presented in this section. These include: cation exchange capacity, particle size, surface area, density, and zeta potential. 3.4.1 Cation exchange capacity The cation exchange capacity (CEC) of a soil is simply a measure of the quantity of sites on a mineral's surface that may be exchanged easily by other cations which are available in solution. The procedure used was the BaCk compulsive exchange method described by Gillman (1979). The basic procedure is to equilibrate the soil with a barium chloride solution. Barium, on the exchange sites, is then replaced by magnesium sulphate. Pertinent measurements are: initial weight of tube and sohds, final weight of tube, solids and solution, and volume of MgS0 4 added. Direct measurements of exchangeable basic cations can also be determined but was not done in this study. The CEC test was used to aid in the determination of the clay mineral content. 45 3.4.2 Particle size, surface area and density Particle size distribution data for each of the HPGR samples was provided by BHP. The size distribution for each of the core samples was determined using SEM and an image analysis technique. To obtain a sample for the SEM, the sample was dusted onto a clean surface and randomLy sampled using 6 individual SEM stubs (1 cm diameter) coated with a sticky carbon tape. Two stubs were viewed using the 100X magnification, two were viewed using the 500X, and the last two were viewed using the 2000X magnification. In each case no two images overlapped. Approximately 30 images were collected from all six stubs. Using an image analysis technique, the average diameter for each particle image was determined. Surface area was determined using a Quanta-Sorb (Quantachrome Corporation, N.Y.). Quanta-Sorb is an instrument which directly measures the surface area of a powdered solid by nitrogen adsorption. Based on the Brunauer, Emmett and Teller (BET) theory, a mono-layer adsorption of nitrogen onto a solid enables the calculation of the surface area of the solid once the quantity of nitrogen adsorbed is known. Dry powder densities were determined using a Beckman Model 930 Air Comparison Pycnometer which provides precise volume measurements (+/- 0.1 cc) of a pre-weighed sample. 3.4.3 Surface electrical properties The objective of this test was to determine the nature and relative magnitude of the surface electrical properties of select kimberhte samples. Ideally, pure mineral samples would be used 46 however, since kimberhte tailings would be a composite of minerals, the surface electrical properties were determined using the whole rock sample. The surface electrical properties of solids in water are determined by measuring the zeta potential (Section 2.2). The best way to measure zeta potential as a characteristic of the electric double layer is to shear off the diffuse layer and measure the potential created or applied. In this research, a Zeta Meter (Zeta Meter Inc., New York, N.Y.) was used to determine zeta potential. This was done by placing a sample in a specially designed cell, applying a potential across the cell and using a microscope to observe and time the moving particles. The particles will move towards either the positive or negative electrode. From the velocity measurements and voltage apphed, the zeta potential can be calculated. Initial measurements were done to determine the nature and relative magnitude of the surface potential, by using an indifferent electrolyte solution of 0.005 M NaC104. (Mackenzie and Lovell, 1971, determined that NaC104 was an indifferent electrolyte.) Samples were prepared by adding 1 mL of a 6% w/v suspension to a 500 mL solution of electrolyte. The mixture was pH adjusted and allowed to equilibrate for 30 minutes. For zeta potential measurements, 20 particles were timed with the zeta meter. The sample in the cell was changed after each five measurements. Zeta potential was determined over a range of pH 3-11. To test the effects on the zeta potential with the addition of a multivalent cation, the samples were prepared by adding 1 mL of a 6% w/v suspension to a 500 mL solution electrolyte mixture of 0.005 M NaC104 and 0.001 M Mg(C104)2. Equilibration time, pH adjustments and measurements followed a similar procedure as detailed above. 47 Effects on zeta potential were also tested using various concentrations of a cationic coagulant. Samples were prepared as 3% w/v solids in solutions of distilled water. The suspensions were allowed to equilibrate at solution pH (no adjustments to pH). Separate samples were prepared for each concentration of coagulant. After 30 minutes, zeta potential and light transmission measurements were made. The suspensions were sampled using a pipette from approximately the same depth. 3.5 F L O C C U L A T I O N TEST WORK Separate flocculation tests were conducted for this research. Select kimberhte samples were tested with the same flocculants and coagulants used by BHP in their pilot test program The flocculants used were high molecular weight, anionic flocculants. They varied in their charge densities, ranging from a low (Percol E10), medium-low (Percol 155), medium (Percol 727), medium-high (Percol 156) to high (Percol 919) anionic charge. The coagulant used was a very high density cationic coagulant (Percol 368). The purpose of the (UBC) tests was to produce a clear supernatant (>90% light transmission) by varying the polymer type and dosage. Only the fine portion (-75 um) of select kimberhte samples were used for this testing. Each sample was tested with the various flocculants. Sample proportions were pre-weighed and mixed in 30 mL test tubes with laboratory distilled water to a desired suspension. (20 % sohds for the HPGR samples; 15% sohds for the core samples.) After the addition of the flocculant, the test tubes were stoppered and inverted 3 times. The suspensions were allowed to settle undisturbed for 10 minutes. A 5 mL ahquot of the supernatant was extracted and placed in a specially designed cell used for light transmission measurements. Based on the results of these tests, the 48 flocculant which gave the best performance, i.e. highest % light transmission, was subject to further testing in order to optimize dosage. Once the preferred flocculant and optimal dosage was determined, the suspension was re-tested in a larger container—a 500 mL glass cylinder. Due to the limited amount of sample available, three cylinder tests were done; one test using a dosage below optimum, one test at the optimum dosage, and one test using a dosage above optimum. The samples were observed for clarity of the supernatant. 49 4.0 TEST RESULTS This chapter reviews the test results from this research. Included are the results of the mineralogical analysis, chemical leach test, surface physical characteristics, and flocculation testwork. 4.1 M I N E R A L O G I C A L ANALYSIS The primary minerals identified are very similar and are consistent with typical kimberhte (Table 2) occurrences with the exception of Panda 3. Figure 12 compares the NWT kimberhte samples to the main composition of kimberhtes and lamproites found globally. All samples, with the exception of Panda 3, plot within tolerable margins for the kimberhte field. Dominant minerals identified include: olivine, phlogopite, garnet, diopside, calcite, quartz, feldspar, serpentine, montmorillonite and clinochlore. The distribution of minerals present from sample to sample, however, does vary (Appendix A). For example, the HPGR samples are relatively coarse grained, with some samples comprised of up to 87% olivine (specifically forsterite — a magnesium end member of the olivine group) (Plates 2 and 3). There are few fines present. In contrast, some of the core samples (Fox and Misery) show extreme alteration, as the primary minerals have been completely replaced by serpentine, montmorillonite and clinochlore (Plates 4 and 5). Anhedral crystals of olivine may comprise 3% of these samples. Leslie, because of its unique history, exhibits a slightly different mineralogy. Monticelhte (Mg-Ca olivine member) and brucite, which may have occurred in the other pipes at some point in time, were observed. 50 K20 MgO A 1 2 0 3 Figure 12: Ternary diagram showing the components of kimberlite and lamproite in terms of wt% K 2 0 , MgO and A1 20 3 (Wilson, 1989). The NWT kimberlite pipes are plotted as symbols, o Panda, • Fox, A Misery, V Koala, and 0 Leslie. Solid symbols are HPGR samples, open symbols are core samples. 51 Plate 2: HPGR Misery sample under plain light. Olivine (clear), garnet (pink), diopside (green) (2cm=lmm) 52 Plate 3: HPGR Fox sample under plain light. Notice the abundance of anhedral crystals. Olivine (clear), diopside (green), garnet (brownish) (2.0cm=lmm) 53 Plate 4: Core Misery sample under polarized light. Note the abundance of montmorillonite (bright, very fine grained) and serpentine (yellow-brown)— forming pseudomorphs after olivine (?) (7.6cm=lrnm) 54 Plate 5: Core Fox sample under polarized light. Note clumps of montmorillonite (brown) and serpentine (yellow) forming pseudomorphs after olivine (3.8cm=lmm). 55 only in Leslie (Plates 6 and 7). There is little or no alteration of the primary minerals observed in Leslie. Individual rock descriptions and XRD (liffraction plots are presented in Appendix A. Using the XRF oxide analyses, CD?W normative calculations were performed. CIPW normative calculations produce a list of mineral components, thought to be the order of mineral crystallization in a theoretical magma. Although this method was apphed to the kimberhte samples and proved to be useful for comparison purposes, the mineralogical descriptions are probably not representative, as some of the kimberhtes have undergone extensive alteration and contamination from wall rock sources. The results of the CIPW normative calculations for the HPGR and core samples are presented in Table 5 and 6. These tables show a variation in the calculated modal mineralogy between and within the five kimberhte pipes. For the HPGR samples (whole rock and -75 um fraction), Table 5 indicates the samples were composed primarily of olivine (26 to 87%). This corresponds with the thin section and XRD analysis of these samples. For Panda, Fox, Koala and Misery, the minerals hypersthene, feldspar (albite, anorthite and orthoclase), corundum and magnesite comprise a significant bulk of the calculated modal mineralogy. Since hypersthene, corundum and magnesite were not identified in either the thin section or the XRD analysis, and the feldspar was identified in only a few samples, it is likely these calculations represent the identified thin section occurrences of phlogopite, garnet, serpentine and chlorite (Appendix A). Calcite comprises between 1.5 - 8% of the modal mineral assemblages which was also observed. 56 Plate 6: Leslie sample under plain light. Garnet is large crystal on the right with a kelphatic rim, monticelhte, large crystal in center showing alteration to serpentine, calcite rhomb in top left corner (3.8cm-"-lmm) 57 Plate 7: Leslie sample under polarized light. Monticellite (white mineral top left), olivine (coloured mineral at bottom left), pervoskite (?) top left corner (pinkish colour), garnet (opaque mineral at right) (2cm=lmm) 58 f UK S-a o J3 u "3 u a 0 a 1 u a o c <U W •H <U eg a o s •a o a ca JD "« &3 IT, H 0) h-l g '•8 rt o o i a I rt o » SI I OH 00 C N * # * # Tt C N * Tt o CO r-C N C N * Tt Tt O N ON C N ON * 00 VO f - H o c-~' o o O r—1 * Tt r> 00 VO »/-> t-* o 00 * * * * C N CO 00 O co C N co o >ri o o d Tt C N co C N * o t> T - H Tt o * CO Tt * * * * t> C N 00 Tt r--o o CO O t> Tt r-' C N o p-' o © CO CO o CO CO T-H Tt 00 00 VO # * * * # 00 t> CO C N o CO * C N r> Tt C N C N Tt o C N o CO IT) O N * O VO r-Tt C N * o ON * # * * ON O < N CO CO o 00 C N Tt 00 00 VO CO o o C N o d CO 00 r-co * * * * >/-> CO * * 00 VO VO * Tt Tt C N O VO C N C N r- * vo VO 00 00 o ' © co C N co * o Tt oo 00 C N VO * ON CO * * * * Tt r~ O N oo o C N ON co CO VO C N O p-' o d d VO r-C N * ~ C N C N * * 00 C N * * # 00 IT) O N Tt U"N o 00 Tt O IT) C N ON o d VO C N Tt o O CO Tt CO p VO 00 * * * * * 00 Tt o vr. # Tt CO CO C N CO r-' o C N d C N ON * VO C N vn 00 Tt C N # 00 00 * * * CO C N VTl CO CO o r> Tt 00 r-C O o '-' C N 1-1 © d CO C N o 6 o •5 a s= w 1 ^ CD J3 O « 5 a> 58 •3 rj O Q ffi O < < u Z ^ Q C / u g < o CD § 59 .2 " lO r-H CN -2 ca o CN &l <u J3 IO cn o a CN i O <-> ro I I I , a |U CN cn x Iii O £ ca . ° Lb •3 CM | PH CN 1 PH o p * * * * CN 00 * CN CN CN r-OS * CN 00 ON o ro ro p * * in o in o O O * * 00 00 ro * 00 # * ON CN <N VO in r-o ON * CO ro CN o in ro O O d r~- *~| * * VO o o CN ** * ro NO * * * CN ro CN m o r—1 Os VO VO CN O m' vd rH o o d d r-ro * CN VO VO * Os VO * * * * 00 CN VO 00 00 o r-ON CN * CN ro ro O in O o d vd " ON * VO CN VO ro •* Os * VO CN * * * # r--CN ro CN VO 00 CN VO CN in vd o ON o d Os ro * * CN o VO ON ON # r-~ 00 * * # IT) VO p CN o VO r-H * ro ON o vd vd CN o d CN <n 00 Ti-ro ro VO m ro ro * * * * * ro >n CN >n CN O VO * * vO •«*• CN ON' CN CN r- o I-H d ON o (N CN 00 m ro 00 00 * * * * * CN CN 00 o CN o * * Os >n >n VO O O o d # * ON 00 ro oo * * * * ON f--CN CN VO ON >n * o VO O O O d vd * * * * ro ro * 00 * * * in CN O r-o CN VO CN vq CN vq O r-' o in O o d ro ro * VO vq p ro * ON ON * * # CN ON CN r- ON ON ro O * in CN O o d r- d * * CN o CN CN * * * * * O ON ON CN 00 ON 00 00 >n >n * 00 O o d ON o MH cu rs •S CO .. g *c3 H K O o K4 cu •S a a 1 r4 P EH S <J <-> N la 11 S3 +Z ca T3 C O 60 in thin section. The CIPW normative calculations for Leslie showed olivine, kahophihte and DiCaSilicate represented most of the calculated modal mineralogy. These calculations likely reflect the occurrences of olivine, monticelhte, brucite and garnet as identified in thin section and XRD analysis. The CIPW normative calculations (Table 6) of the core samples do not correspond well to the thin section observations and XRD analysis. As mentioned previously, because of alteration and contamination of wall rock sources, the CIPW calculated mineralogy may not reflect the true mineralogical composition. In both thin section and XRD studies, all samples except Leslie show alteration to serpentine, montmorillonite or clinochlore. Both Fox and Misery contain a greater abundance of montmorillonite (35-50 %) while Panda and Koala contain more clinochlore (7-10%) (Appendix A). Leslie contains traces of serpentine. All the samples, with the exception of Leslie, show signs of contamination. Mitchell (1986) discusses the problems of contamination and the various attempts at estimating the degree of contamination or alteration of kimberhtes. Weathering of primary minerals to mixtures of chlorite, montmorillonite and serpentine leads to increased Si02 and AI2O3 as the soluble cations are removed. Figure 13 demonstrates the effects of contamination in terms of Si02 and AI2O3 on the NWT kimberhtes using Mitchell's (1986) work. 61 20 15 5 - 0 I 1 1 1 1 1 • s 1 o - 8 a y ^ • — • — / / • • • Contamination free kimberlites < 1 1 / ^ ^ S * . i i • 1 30 35 40 45 50 55 GO Si02M*) Figure 13: Relationship between A1203 and Si02 in contaminated and contaminate free Jdrnberhtes (Mitchell, 1986). The solid lines are simple mixing lines between various crustal contaminants as weathering products. The NWT kimberhte pipes are plotted as symbols, O Panda, 6 Fox, A Misery, V Koala, and 0 Leslie. Open symbols are HPGR samples, solid symbols are core samples. 62 4.2 C H E M I C A L L E A C H TESTS Two separate chemical leach tests were conducted and are discussed in this chapter. They include the results of the pH leach test, and olivine dissolution test. The purpose of these tests was to better understand how kimberhte behaves when deposited in an aqueous environment. For example, test work done by others (Rescan, 1995) have shown that aluminum is released in sufficient quantity that it may represent a toxicity to the aquatic system Test results are given in Appendix B. 4.2.1 pH leach test It is well documented that minerals vary widely in their stability or their solubility in water. Kimberlite rock, being comprised largely of magnesium silicates, tends to react rapidly in water and has an alkaline pH (Drever, 1982; Luce et al., 1972). This was found to be true for the NWT kimberhte samples. Mixing these samples with laboratory distilled water (pH 5.96) resulted in pH readings between 8 and 10.5, with Panda recording the lowest pH and Leshe the highest (Table 7) (Appendix B). Total metals (of those analyzed) leached are presented in Figure 14 in terms of mg/kg. These profiles show that kimberhte tailings deposited into a solution at or near a neutral pH, will release more metal ions than if they were deposited into an alkaline environment. From Table 7, it can be concluded that magnesium and calcium are the major contributors to the cations released— aluminum was not a significant contributor. 63 ta +-> •s ee s OH <+H o cn 3 H PH ca K4 If T3 C3 •8 <a T 3 r*5 I d 1 •8 c IE °' IS HH •p. C J (1) H OA 0) ca ro ro NO ON r- r r 00 o NO CN NO ro o ro ' — 1 ON CN 00 00 ro CN 00 m ro ro i — 1 o <n ro 00 d NO NO' ro r-' , — ' ro in d ON ON d t- r--m CN CN m r r m rT O r r o o o ro (N 00 i—* o ro NO i—i T—1 CN o CN CN TT ~ CN o O O o o o o O p O p o O o O d d d d d d d d d d d d d d d o o 00 o o Os o o o o o o o o 00 <—i in o 00 00 p NO o r H ON o ' — 1 i — ; d CN CN d CN >n ro Os CN Os I—' ON d ON i — ' ON m NO CN NO r r I -H CN >n SO CN ro 00 o o o O O O o o o o o O o o O o r f r r O I T l Os 00 1—1 r r r r o ON 1-H o o o d CN fH NO ro CN r f r--' NO Os ro r- r--' CN CN CN i—l Os NO ro IT) r r T—1 r r ro 1—H ON rT rT ON 00 r r O o O o ON o o CN o NO r-NO - H - h 00 00 in o r r r r ON NO CN m CN Os >n ro Os CN sd CN in 1—<' 00 rr' 00 d d —i rl- r r o o O O CN CN O o ,_, o NO o o o O o O O O ro o o o r- O ON o o o d d d rr' d in d d d d d d d d d o o o r- O o o OS o o o o o ro o o NO ' — ' NO CN o CN ro o 00 NO o p d ro CN 00 >n NO CN r H ro in OS d CN i — ' NO CN CN m 00 CN CN i—< r r r-CN ro n- CN ro o o O O O O o sq in r r CN 00 CN d ,—i r f d d NO ro ro CN in O O o O o O o o o O O Os o o O in o o CN PH NO in ON NO 00 Os ON ro i - H r r 00 Os ON m ro r r in r t in ro 00 ro o NO O in SO rT CN o o o CN r H i—< r r r r r r r r ro r r rT CN 00 00 00 d d d 00 00 00 00 00 00 d d d o o o o o o o o o o o o o o o o o p o o p p o p o p p p o p ON I—I t~~' ON r-' ON i—i r-' ON 1-H ON 1-H -3 PH o PH 3 0) HH 64 CD CD CP _c o o CD _OT O -t—' CD O o 3 0 0 0 2 5 0 0 2 0 0 0 1500 1 000 500 0 i — i — i — i — i — i — i — i — i — i — i — i — i — i — i — r ^ i p H 7 9 1 1 7 9 1 1 7 9 1 1 7 9 1 1 7 9 1 1 P a n d a Fox M i s e r y K o a l a L e s l i e Figure 14: Bars on graph show the total metals leached for each of the NWT kimberhte pipes at various pH's in terms of mg/kg 65 However, under alkaline conditions, both magnesium and calcium will precipitate, leaving much lower concentrations in solution. These changes can be accounted for by reviewing species concentration plots verses pH for magnesium and calcium (Figures 15 and 16). The major species of magnesium in solution is Mg 2 +. Not until the solution reaches a pH value of 10.6 where Mg(OH)2(S) precipitates does the concentration of Mg 2 + drastically decrease. It is the same for calcium, as Ca 2 + is the major species until pH 13 is attained and Ca(OH)2(S) begins to precipitate, removing calcium from solution. The calculated mineral components of the HPGR kimberhte samples determined the Mg 2 + could result from the dissolution of olivine, diopside, hypersthene or magnesite. Olivine was determined to be the primary mineral. Calcium could result by the dissolution of calcium carbonate or diopside or apatite. The same CIPW normative calculations were done on major oxides of the post leach XRF analysis. These calculations are presented in Table 8. A review of this table shows that some of the minerals tended to decrease in modal %, others only slightly decrease or did not change at all, and others tended to increase in modal %. These changes are thought to indicate the relative solubilities of the minerals present. For example, minerals which tend to decrease in modal %, represent minerals with a high solubility when compared to the overall leaching rate of the solids. Minerals which shghtly decreased or did not change are minerals only slightly soluble. Minerals that tended to increase in modal % are relatively insoluble when compared to the overall leaching rate of the solid. Olivine indicates a tendency for a high solubility; calcite shows a moderate solubility, with the exception of Leslie which shows a high solubility for the calcite bearing minerals. 66 pH value Figure 15: Concentration of magnesium ions as a function of pH (MacKenzie and LovelL 1971) 67 pH value Figure 16: Concentration of calcium ions as a function of pH (MacKenzie and Lovell, 1971) 68 ON * ON m T t 00 * T t T t * * 00 in 00 m 00 o ON O o in 5 Q . C O T t ON C N ON d d l > in Misery O N C N * C O N O 00 C N * N O O * * N O 00 m 00 o ON O C N O N Misery X a 00 C O T t C O ~ d d d d r--' m r- ON * C O C N O * * O O * * ON T t m o C O N O o p x a T t C N " d d d in r-C N * C N C N * * 00 C N * 00 m ON T t in o 00 T t m 8 PH CD H d IT) in C N ON d d N O m 1—H 00 C O m 00 r--N O in 00 N O N O * * * * 00 ON O N C O in 00 * S a C O r- C N C N T t r- d C N d C O ON ON r-C N O * 00 00 C N N O ON in * * 00 O N T t T t o T t Fox a N O C N C O 00 d d C N d d r- 00 o o 00 00 C N 1-- ON N O * * # C O o in m 00 ON * X a C N t- C O C N C O co 00 -~H C N d Pre- C N T t o O C O T t C O o N O 00 * * * 00 T t l-H o in * Pre- CO CD H T t r> C O C O C N C O d C N d C N 00 00 # C N T t T t 00 00 C N * 00 C O * * * C N C O 00 C O T t o ON C O o a r--' N O C O d d C O d d C O ON Panda ON C O in * in N O m 00 * * in in * * * C N C O ON C O T t o o C O C O Panda X a. ON N O T t d C O ~ d d C O ON r> C N C N * o C O N O 00 ON C N * T t m * * * T t C O T t T t o C O C O r-NO E a ON N O C O d d C O " d d C O • ON * N O C N in 00 T t C N * 00 00 * * * C O C N m C O C O o r~ T t 00 8 PH C/3 CD H 00 m d C N d d C O C N O J £ £ % 9, «f § 3 9, g g 8 8 S M z u . u CD •is a S S 1 -S 2 3 3 x .o « o i " 3 y O £ ^ Q o 3 ^ 3 69 CM i l l PH H >n vci NO m * rr re' NO l/-> * o * ON r H T j - i n O N » n r H c n * C N C - <T1 >n I N m O N -H o rr oo o rn o m * rH * in 00 * in rr so r- * ro O f- rr rn vo O N N O CN r~ m m H CN d r~- oo d rn' d m IT lONrr iNOrrONrH* CN ON NO m rn rN 00 NO NO NO rH O NO C-~ O rH O i n * * oo N O rr C N N O C N cn sq rn -rr o C N r-~ H oo oo d rn ' d cn est ° * O m O O rr rH O 00 in I-H rn' C N cn o r-~ o rn' CN cn ON * CN rr rr NO C N * in NO C N O f- < N O N O rH S O rH CN O O Os CN CN rH SO O rH SO r-C N d d f- rH oo o ON rf CN PH H rH # CN d CN C N * cn rH oo r> * Os Os NO C N rH O m O 00 CN * rT 00 so m CN ON * cn S O S O O t- rH o N O r n oo rn C N d d r- N O C N rT ON o h 00 H C N >n r-~ os m m SO rH CN rH O O O SO o o H-o w5 PH ^ a n "} O 9 n O O O r S a s s S ^ l ^ ^ e g y S £ JS s a i l HO 3 CO g « -5 8 a ^ o « o ,& n 5 O K4 Q I •C CL) $6 CD u 70 From Figure 14, it is also shown that the NWT kimberhte pipes will release metals at different rates when deposited in an aqueous environment. Since the bulk chemical properties of each of the kimberhte pipes have been shown to be different, it is not surprising that this research found the metal leaching rates to vary between pipes. 4.2.2 Olivine dissolution test It is speculated that the alkaline pH found in process waters is the result of olivine being crushed and ground during the d u l l i n g , blasting and crashing of kimberhte. It is proposed the grinding and crushing of the olivines produces very fine, less stable, more soluble particles. Results of the two dissolution experiments are shown in Figures 17 and 18 which graphically display the changes in pH and magnesium over the 96 hour period. SEM images showed that the removal of the fines by ultrasonic washing was effective (Plates 8 to 11), leaving few fine particles attached. For the unwashed sample, the initial pH started at 9.4 and fluctuated by only 0.5 pH units over the period of sampling. Magnesium concentrations were reduced considerably from a high of 17 mg/1, to a low of 5 mg/1, then showed a steady increase after the first 3 hours. Based on the initial pH value it would appear the sample was over-saturated at startup and in fact, a precipitate was observed at startup. For the washed sample, the initial pH was 6.2 and showed a steady increase up to pH 8.7 over 96 hours. The magnesium concentration started at a much higher concentration (54 mg/1) and showed a steady decrease to 36 mg/1 over the 96 hours. No precipitate was observed over the 96 hours. 71 6 0 5 0 E 4 0 3 0 § 2 0 c o o 0 i r "i 1 r PH Magnesium J , I , I , L _j i i i i i i_ J I L 0 8 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 0 T i m e ( h o u r s ) Figure 17: Test results from the unwashed olivine sample showing changes in pH and Mg concentrations over 96 hours 2+ o 6 0 5 0 L> 4 0 3 0 c O C o o 2 0 1 0 0 i i i r T ~ — r j i i L pH Magnesium I 1_ 0 8 7 6 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 0 Figure T i m e ( h o u r s ) 18: Test results from the washed olivine sample showing changes in pH and Mg 2 concentrations over 96 hours 72 Plate 8: SEM photo of olivine crystal showing attachment of fine particles Plate 9: Close up view of Plate 8 showing attachment of fine particles 73 Plate 10: SEM photo of washed olivine crystals showing that most of the subfine particles have been removed Plate 11: Close up view of plate 10 showing most of the subfine particles have been removed 74 These results suggest that grinding has created artifacts on the surface of the olivine, which results in an accelerated initial dissolution rate. In the unwashed sample, the precipitate at startup indicated an over-saturation of magnesium due to the immediate dissolution of the ultra-fine particles. In the washed sample, after the initial dissolution of ultra-fines, the dissolution rate compares to those found by Grandstaff (1980) and others (Schott and Berner, 1985; Brady and Walther, 1989; Stumm and Wollast, 1990). Their work showed that olivine dissolution rates are determined by surface reactions and tend to follow a linear trend. One study, Holdren and Berner (1979) provided evidence that the dissolution of olivine was the result of the grinding procedure which produces a large number of fine particles. If these particles were removed, a linear rate law was observed not the parabolic rate law as previously documented (Luce et al, 1971). In fact, SEM images (Plates 12 and 13) from this study, show controlled etch pits on the mineral surface of the washed sample, indicating that the dissolution occurred preferentially along lattice imperfections. 4.3 S U R F A C E PHYSICAL CHARACTERISTICS Results of the surface physical characterization tests are presented in the following sections. These test include cation exchange capacity, particle size, surface area, density and zeta potential. Test results are given in Appendix C and summarized in Table 9. 4.3.1 Cation exchange capacity The determination of cation exchange capacities was included in this test work to aid in the identification of the clay minerals. Different types of clay particles tend to have specific ranges of 75 Plate 12: Olivine after 96 hours of leaching. The olivine crystal is showing signs of etching indicating mineral dissolution Plate 13: Similar to plate 12. Signs of mineral dissolution obvious in etching patterns 76 o Os N CN Os O O O O O r-H r H lO in m in o m co CN CN co CN O CN CN CN O O ro m CN o o m co o 2 m >n CN CN o CN cu S3 CU &H .© t cu ca 44 cu cu • H -r>> 44 CL, CU u « a s cu H CD 1 O 0 1 <H PH CD O O >n o o o o ,H- r-H in r-~ in so O O so so ^ S w 2 10 8~ "o "o "o "Q o o o o tH tH lH tH 53 53 53 53 53 • PH PH .PH PH PH O cn SO in CD PH SO in 53 PH oo cn oo so m O m in o W CD PH O m in o "o u o PH O m SO in CD PH O cn CN r-& PH s 8 •8 "e cn • in m H H in in r r r r so H r n ' os rf cn CN m 00 m cn Os cn ro r--Os cn so cn CN rT ro in o O o ° f Os SO r^ m CN cn Os O r H o Os h i^ l h O OS CN r H co| r~» so in oo d r H CN r H in SO r H oo so so r H CN CO CN rT SO m CN O so Os rf CN CN CO 00 oo in co in r H ro CN 00 00 in rr rT so SO o SO CN 1 Os 00 t> CO CO CN CN r H o o in s q rT s q s q m m s q m o CO CO CO CO CO CN CN CN CN CN CN CN CN CN CN CN CO CD N t/3 CD "3 C3 PH o o o o o o in o m in oo m so so co r H OS CO CN r H r-H 2 CO o CN in r r CN O GO 8, O-J o 00 . r r r r ^ . 2 oo oo 2 r H tN OS Os Os rf CN 00 <n so Os Os CO Os os r~-Os Os "T3 PH CD H H PH P4 o4 rg P4 & o o o o o Si & & & & r H r H H H H H H H r n cN CO rT f i l l PH PH PH PH >-H rs co S S >< o o o PH PH PH r H CN CD CD Ui Ui r H CN "re "re o o ^ h^H CD r-I 77 cation exchange capacities (CEC). Table 10 shows the cation exchange capacities of common soil constituents (Drever, 1982) which can be compared to those of the NWT kimberhte samples shown in (Table 11). The samples are of mixed clay components as determined by the mineralogical studies. It is presumed that the wide variability in the CEC values recorded reflect these variations in the mineral components. CEC values for the HPGR samples tend to be lower than the core samples. This result likely reflects the lack of fines in the HPGR samples. Samples with a high proportion of montmorillonite (i.e. Fox and Misery) indicate a high CEC value. 4.3.2 Particle size, surface area and density SEM examinations revealed particles of a great range in morphology and size. However, the homogeneity of form throughout the samples is remarkable considering the heterogeneity in the parent rocks as shown in Plates 14 and 15. Particle size distribution graphs are given in Appendix C. For the HPGR samples the average size (50 %) distribution ranged between 350 to 800 um with less than 4 % being considered fines (1-10 um ). For the core samples, the average size ranged between 7 to 50 um (Table 9). Fox and Misery had the greater percentage of fines present. This corresponds with the petrographic observations that the HPGR samples had fewer fines present. Surface area calculations for a single point BET analysis for select kimberhte samples are given in Appendix C. Surface areas, given as m2/gm, range from 1.53 to 9.45 for the HPGR samples and 7.42 to 38.52 for the core samples (Table 9). As expected, the core samples, which had more fines present, had a greater surface area. 78 Table 10: Cation exchange capacities (meq/lOOg) of common clay minerals Clav CEC Smectite 80-150 Vermicuhte 120-200 Illite 10-40 Kaolinite 1-10 Chlorite < 10 (Drever, 1982) Table 11: Cation exchange capacities (meq/lOOg) of the NWT kimberlite sample Kimberhte sample CEC Primary clay component(s) HPGR Panda HPGR Fox HPGR Misery HPGR Koala HPGR Leslie Panda 1 Panda 2 Panda 3 Fox 1 Fox 2 Fox 3 Misery 1 Misery 2 Koala 1 Koala 2 Leslie 1 2.79 7.56 15.03 17.19 10.9 15.39 28.72 10.61 21.85 42.66 63.61 29.05 24.62 13.83 34.58 7.82 serpentine, chlorite serpentine, chlorite serpentine, chlorite, montmorillonite chlorite, montmorillonite serpentine serpentine, montmorillonite, chlorite serpentine, montmorillonite, chlorite chlorite, montmorillonite, serpentine montmorillonite, chlorite montmorillonite, chlorite montmorillonite, chlorite montmorillonite, chlorite montmorillonite, chlorite serpentine, chlorite chlorite, serpentine serpentine 79 A density comparison between the two sample groups vary. The predominance of olivine (S.G. 3.2) and lack of fines account for the higher densities found in the HPGR samples. 4.3.3 Surface electrical properties Results of the zeta potential test work are graphically presented in Appendix C and summarized in Table 9. Zeta potential measurements are used to show the pH range at which the particle surface has cation or anion exchange properties, and also the pH range in which stable colloidal suspensions can form Previous work by O'Gorman and Kitchener (1974) (Section 2.2) showed that kimberhte had a high zeta potential of -77mV. This research showed the zeta potential not to be as high with an average plot between -15 to -35 mV over the tested pH range (Figures 19 and 20). There was no sign reversal except in the case of Panda 3 and Leslie 1 which both showed a tendency towards a positive surface potential below pH 6. Most samples have a surface potential in which slow coagulation could occur ( ± 20mV). In fact, as shown in Plate 16 some of the kimberhte suspensions if left undisturbed for 24 hours will naturally coagulate and settle (with the exception of HPGR Fox and Koala, Fox 1 and Misery 1). Magnesium ions were found to be effective in reducing the zeta potential of the kimberhte to values between +10 to -15 mV (Figures 21 and 22). Above pH 10 the zeta potential measurements were strongly positive and probably reflect Mg(OH)2 precipitates as observed through the zeta meter microscope. 81 30 > c 0) o CL M 20 -10 -0 •10 •20 •30 -40 •50 average maximum minimum _ l , I u_ 6 7 PH 8 10 11 Figure 19: Plot showing the average, maximum and miriimum zeta potential values for all the HPGR samples in a solution of 0.005 M NaC104 > E c o Q_ CD N 30 20 minimum p H 10 11 Figure 20: Plot showing the average, maximum and minimum zeta potential value for all the core samples in a solution of 0.005 M NaQC>4 82 Plate 16: Settling test on select kimberlite samples. Note that some of the samples are clear indicating natural coagulation has taken place. 83 3 4 5 6 7 8 9 1 0 1 1 pH Figure 21: Plot showing the average, rmximum and minimum zeta potential values for all the HPGR samples in a mixture of 0.005 M NaC104 and 0.001 M Mg (C104)2 Q_ - £ - 3 0 - • a v e r a g e M - » m a x i m u m — 4 0 - T m i n u m u m _ 5 0 1 i i i i i i i i i i i i i , i i i -3 4 5 6 7 8 9 1 0 1 1 pH Figure 22: Plot showing the average, maximum and minimum zeta potential value for all the core samples in a mixture of 0.005 M NaC104 and 0.001 M Mg(C104)2 84 Inorganic coagulants act much like a multivalent cation in that they specifically adsorb on the particle thus reducing surface charge sites. In some cases the addition of a coagulant promoted a quick settling and a clear supernatant. This, however, was not always the case. Most HPGR samples did not produce a clear supernatant. Figure 23 demonstrates that the addition of too much coagulant results in re-stabilization of the suspension. This results because the polymer wraps itself around the particle and forms a protective, positively charged coat. This can be attributed directly to the quantity of fines present. 4.4 F L O C C U L A T I O N TEST WORK Results of the flocculation test work on the NWT kimberhtes are presented in Appendix D and are summarized in Table 12. This table includes the results done for this research (UBC) as well as results from BHP laboratory and on-site tests for comparison. Examples of the UBC tests are shown in Plates 17 and 18. Test results show of the five types of flocculants tested, only two were preferred: Percol E10, a low density charged flocculant and Percol 156, a medium-high density charged flocculant. One pipe, Fox, required the addition of a coagulant Percol 368. Dosages required to produce a clear supernatant ranged between 23 (HPGR Panda) to 525 (Misery 1) gms/tonne. Figures 24 to 27 show the various responses the kimberhte suspensions had to E10 and 156 in terms of light transmission (%). There are obvious preferences in terms of flocculant type and dosages required for each pipe. For example, Misery and Fox responded only to E10, while Panda, Leshe and Koala gave varying responses to both E10 and 156. In general, the HPGR samples (except Fox) 85 > E c CD •A-' O D_ O -t—' CD N — 40 0.0 . 0 .5 ' 1.0 1.5 2.0 ppm of Perco l 368 100 90 80 c 70 _o OT OT 60 E OT C 50 o I— 40 -t—' sz CD 30 20 10 0 2.5 Figure 23: Coagulation test on HPGR Misery. Note as the concentration of coagulant increases the zeta potential changes to positive, so much so that the particles start to repel one another (i.e. light transmission decreases) 86 C3 I* HH •3 -3 -3 o ro CN t--o m si5 m o in so o SO >n o >n <n o m o m o W £ 0 0 o So •—1 so o o o s SO >n o ro SO * * m rr SO <n o >n ro SO in o o in o o ri-se in in m SO in o o CN O oo SO in ro r— ro so 00 SO ro O O in >0 CN O 00 r H SO W ro o in SO in o o ro O in CN so in s tn m 12 "3 O o so in so in o in ro CN SO m SO O 1 — 1 m o in in oo >o SO O CO o SO o ro so in 8 ^ H ro o °° S so m ™ cu CU •t-> bo V\ CD d -g t> rd ,3 rH -c3 ecf g ^ CD W VH CU <p o I & o o r>> T3 -O CD CD -U & 5. O err1 HH) CD CD eg. o 00 SO ro *o o !H CD PH CD 1 CD C7j 00 o eB O f r H ^ § 2 2 o o o p r H CD CD PH PH CO j _ , CD CD 1^ CD 3 rg 5 M d « i r - H 8 CD . „ Vi (1> g g CD d • g d o o CD VH CD 3 o o eg CD rO CD r-H Cfl P d C J o 1 * rS 0 rO • cn p vt o x ""1 © W HH CD* CD OH O a r-C3 X CD VI H « d H UH * * 87 Plate 18: Flocculation test for Misery 1 using Percol E10. Dosage of flocculant in test tubes 1 through 5 are: 444, 476, 489, 511 and 556 gms/tonne respectfully. In % sohds test, Percol E10 was used at a concentration of 16 ppm 88 c o CO CO CO c o 1 00 80 60 40 20 0 F l o c c u l a n t P e r c o l E10. P a n d a Fox M ise ry K o a l a L e s l i e 0 350 50 100 150 200 250 300 gm/tonne of Flocculant Figure 24: Flocculation test on HPGR samples using various concentrations of Percol E10 c o co CO CO c o 1 0 0 8 0 6 0 4 0 2 0 h 0 ZK. r * -o-</°' F l o c c u l a n t P e r c o l 156 -1 1 —i r -->• . 1 . P a n d a Fox M ise ry K o a l a L e s l i e 0 5 0 3 5 0 1 0 0 1 5 0 2 0 0 2 5 0 3 0 0 g m / t o n n e of F l o c c u l a n t Figure 25: Hocculation test on HPGR samples using various concentrations of Percol 156 89 Panda 1 Panda 3 Misery 1 Koala 1 Leslie 1 0 0 0 0 2 0 0 3 0 0 4 0 0 5 0 0 g m / t o n n e o f F l o c c u l a n t Figure 26: Flocculation test on core samples using various concentrations of Percol E10 c o CO CO CO c D SZ 1 0 0 8 0 6 0 4 0 h 2 0 0 0 Flocculant Percol 156 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 ° Panda 1 » Panda 3 ° M i s e ry 1 * Koala 1 • Leslie 1 g m / t o n n e o f F l o c c u l a n t Figure 27: Flocculation test on core samples using various concentrations of Percol 156 90 responded to Percol 156 at a dosage of approximately 50 gms/tonne, whilst the core samples (except Misery ) also responded favorably to Percol 156 but at a much higher dosage of 125 gms/tonne. Figure 28 shows the test work conducted on Fox 1. Without the addition of a coagulant, flocculant dosage of Percol E10 would exceed >1100 gms/tonne for Fox 1. 91 1 00 200 400 600 800 1000 1200 gm/tonne of Flocculant • E10 ' E10 with 138 g m / t o n n e 368 • E10 w i th '277 g m / t o n n e 368 Figure 28: Flocculation test for Fox 1 using Percol E10 as a flocculant and Percol 368 as a coagulant 92 5.0 CONCLUSIONS AND RECOMMENDATIONS This chapter surnmarizes the findings of this thesis by discussing the objectives presented in Section 1.1. The primary objective of this thesis was to investigate the physical and chemical behavior of kimberhte fines and their interaction with the aqueous environment. To observe these characteristics, kimberhte suspensions were subjected to the processes of coagulation and flocculation. A suspensions response to these processes and its intrinsic ability to resist sedimentation is governed by many factors, including: • the physical and chemical characteristics of the solid particles present; • the solution chemistry mcluding pH and the type and quantity of dissolved ions present; and • the surface charge and charge density on the polymer molecule. For this study 17 samples representing 5 kimberhte pipes were tested—twelve of the samples were received as whole core pieces; five of the samples (HPGR) were precrushed using a high pressure grinding roller process. The HPGR samples were thought to be representative of the ore feed which will be reproduced during the actual processing of the kimberhte on site whereas the core samples were artificially crushed at UBC. 93 This research has shown that each of the NWT kimberhte pipes responded differently. In order to produce a clear supernatant, both the type of flocculant preferred and the dosage requirements varied. For example: • the HPGR samples and the majority of the core samples required a medium-high density, anionic flocculant (Percol 156), but the core samples required a dosage of 125 gms/tonne, 2.5 times that of the HPGR samples; • core samples from Fox and Misery responded only to a low density, anionic flocculant (Percol E10), but required very high dosage of between 550 to 1100 gms/tonne. The addition of a coagulant (Percol 368) significantly improved the dosage requirement; and • Leshe core samples gave the best results when flocculated with a medium density, anionic polymer (Percol 727). To investigate these behaviors a detailed study on the physical and chemical characteristics on each of the kimberhte pipes was completed. A review of kimberhte geology and the geology of the NWT kimberhte pipes, showed that each of the NWT pipes tended to have unique emplacement and post alteration histories. From the mineralogical study, the minerals identified were shown to be typical of kimberhte occurrences. These minerals included: olivine, phlogopite, garnet, diopside, calcite, serpentine, montmorillonite, clinochlore, feldspar and quartz. However, a bulk chemical comparison between samples indicated a wide variation in the modal distribution of these minerals. This is due mainly to the presence of alteration clay-type minerals. 94 The degree of alteration and the presence of these alteration minerals affects many of the physical characteristics. A particle size analysis showed that 50% of the HPGR samples ranged between 800 to 350 um In comparison, 50 % of the core samples ranged between 50 to 6 um. This can be directly attributed to the alteration minerals (montmorillonite, serpentine and clinochlore) present in the core samples but absent in the HPGR samples. Samples which exhibited extensive alteration (i.e. Fox and Misery) also have a greater total surface area. Density measurements also reflected the presence of the less dense, clay-type alteration minerals as these minerals are generally less dense than their primary mineral counterparts. During the processing of kimberhte ore, many of these clay type particles are left in suspension which will be deposited as tailings. It is well documented that these particles, under alkaline pH conditions, will take on a high negative surface charge which results in the formation of stable suspensions. This was found true for some, not all of the NWT kimberhte suspensions. For this study, the zeta potential measurements showed the kimberhte particles exhibit a negative charge ranging between -15 to -35 mV over a pH range of 3 to 11. Albeit not as high as those found by O'Gorman and Kitchener (-77 mV), this range of charge would account for some kimberhtes forming stable suspensions while others naturally coagulate and settle. This study has also shown that some suspensions could be easily coagulated by reducing the zeta potential to near neutral values with the addition of a multivalent metal cation (Mg2+) or an inorganic coagulant. The significance of reducing the zeta potential was to reduce the repulsion between particles, and between the particle and polymer, thus enabling Van der Waals attraction forces to predominate. 95 Chemical leach tests showed that these metal cations are readily available and that the pipes vary in their tendencies to release these cations. For example, Leshe will leach metal cations 100 times the rate of Panda in near neutral pH waters. In kimberhte suspensions where alkaline waters predominate, this rate is reduced dramatically. Based on the above findings there is no obvious answer as to why one kimberhte sample would preferentially require a particular type of polymer molecule. There are many physical and chemical characteristics which are similar and many which differ between the kimberhte samples. There is, however, one mechanism which clearly plays a significant role. It is the capacity for Mg 2 + (and possibly Ca2+) to act as a coagulant and reduce the repulsion forces between particles and polymers. For example, most of the samples preferred a medium-high anionic flocculant to produce a clear supernatant. These samples have a moderate zeta potential and they tend to have a pH of 9; indicating that Mg 2 + is still in solution and available. (If the repulsion forces were not reduced by the Mg2+ion, these particles could reject a polymer molecule which also carries a high negative charge density.) Due to the reduction in the repulsion forces, the particles and polymer will attach. With a high density of binding sites available on the polymer, more particles will be attached, thus the more effective the flocculant will be. In the case of Fox and Misery, which preferred a low anionic charge flocculant polymer, it is postulated the Mg 2 + ion was not available (i.e. precipitated as brucite or serpentine above pH 10). Therefore, a less densely charged polymer molecule would have a better chance of being accepted. However, because there are fewer sites on the flocculant to bind to, more of the polymer is required. For these samples the addition of a cationic coagulant helped to reduce the flocculant dosage. 96 What is evident, and is documented extensively elsewhere, is the function surface area has on dosage requirements. When comparing the HPGR samples to the core samples and in pipes where the alteration of primary minerals is extensive and clay remains as a final product, a higher dosage of flocculant is required for a clear supernatant. This study has shown that flocculant preference of the kimberhtes appears to be related to the interaction of particle and polymer as a function of solution chemistry. It is possible the high solubilities of the minerals involved and their interactions under different pH conditions influence the efficacy of the polymers and their interaction with charged particle surfaces. From the test work conducted the following observations have been made: • there is no one variable which sets apart why one flocculant should be preferred over another. Both a low anionic strength polymer (Percol E10) and a medium-high anionic strength polymer (Percol 156) gave good flocculation results within a variable range of conditions; • pipes which produce a highly alkaline pH and that have been heavily altered or contaminated, such as Fox and Misery, benefit from the addition of a coagulant prior to flocculation to reduce dosage requirements. Flocculant preferred in this case is Percol E10; • dosage rates are clearly a function of surface area. The core samples required 2.5 times the dosage rate than did the HPGR samples; • solution chemistry and the release of Mg 2 + and Ca 2 + ions from the dissolution of minerals appears to play a significant role on the effectiveness of the flocculant. It is possible these ions in solution act to: reduce electrostatic repulsion between particle-particle and particle-97 polymer, promote chemical bonding bridges between particle-polymer, and govern the solution chemistry (pH and ionic strength) which affects for example the polymer configuration in solution. The second objective of this thesis was to develop a better understanding of how kimberhte tailings will behave in an aqueous environment. From on site experience, if the kimberhte tailings are left untreated, the pond or lake into which they are deposited will experience a high turbidity. This turbidity is the result of the repulsion between clay particles due to their surface charge. These repulsion forces prevent the particles from coming together and also retard settlement by keeping the particles in constant motion. The high surface charge exhibited on the particles is the result of the alkaline medium into which they are deposited. Over time, if left undisturbed, these fines tended to settle. This process is quite clearly a function of dilution and pH reduction, and possibly the dissolution and subsequent adsorption of magnesium ions — which reduce the zeta potential inducing coagulation of the particles. This research has also shown that the deposition of untreated kimberhte tailings into natural pH waters will release a considerable quantity of dissolved metal cations, namely magnesium and calcium, which in all probability, will exceed water quality criteria. However, should these metal rich waters be aerated to incorporate C0 2 from the atmosphere, magnesium and calcium carbonates could precipitate thus reducing the metal cation concentrations. 98 Although suspensions from some pipes will naturally coagulate and settle out, the pretreatment of the tailings by flocculants to remove fines will negate both the turbidity and possibly the dissolved metals released. Flocculation selection and dosage are unfortunately sample specific and will need to be tested subsequent to processing to determine optimization controls. 99 REFERENCES Barnes, I., LaMarche, V.C., Himmelberg, G. (1967). Geochemical evidence of present day serpentinization. Science 156: 830-832. Barnes, I., O'Neil J.R, Trescases, J.J. (1978). Present day serpentinization in New Caledonia, Oman and Yugoslavia. Geochemica et Cosmochimica Acta 42: 144-145. Barnes, I., O'Neil J.R. (1971). Relationship between fluids in some fresh alpine type ultramafics and possible serpentinization, Western United States. Geol. Soc. Am Bull., 80: 1947-1960. Berg, GW. (1989). The significance of brucite in South African kimberhtes. Kimberhtes and Related Rocks, Volume I. Their Composition, Occurrence, Origin and Emplacement. (Ed.) Ross, J., Proceedings of the Fourth International Kimberhte Conference, Perth 1986. GSA Special Publication No. 14: 282-296. Bergman, S.L. (1987). Lamproites and other potassium-rich igneous rocks: a review of their occurrences, mineralogy and geochemistry. Alkaline Igneous Rocks. (Eds.) Fitton, F.G., Upton, B.J. Geological Society of London, Special pubhcation No. 30: 103-189. Brady, P.V., Walther, J.V. (1989). Controls on silicate dissolution rates in neutral and basic pH solutions at 25° C. Geochemica et Cosmochimica Acta 53: 2823-2830. Chou, L., Wollast, R (1984). Study of the weathering of albite at room temperature and pressure with a fluidized bed reactor. Geochemica et Cosmochimica Acta 48: 2205-2217. 100 Clement, C R , Reid, A.M. (1989). The origin of kimberhte pipes: An interpretation based on a synthesis of geological features displayed by Southern African occurrences. Kimberhtes and Related Rocks, Volume I. Their Composition, Occurrence, Origin and Emplacement. (Ed.) Ross, J., Proceedings of the Fourth In International Kimberhte Conference, Perth 1986. GSA Special Publication No. 14: 489-504. Drever, J.I. (1982). The geochemistry of natural waters. Prentice Hall: 388 pp. Eggler, D.H. (1989). Kimberhtes: how do they form? Kimberhtes and Related Rocks, Volume I. Their Composition, Occurrence, Origin and Emplacement. (Ed.) Ross, J., Proceedings of the Fourth In International Kimberhte Conference, Perth 1986. GSA Special Publication No. 14: 489-504. Gillman G.P. (1979). A proposed method for the measurement of exchange properties of highly weathered soils. Aust. J. Soil Res., 17: 129-39. Grandstaff, D.E. (1980). The dissolution rate of forsteritic olivine from Hawaiian beach sand. 3rd Proceedings In International Symposium Water Rock Interactions, Edmonton Alberta: 72-74. ' Hatverson, F. (1987). Selected physical-chemical aspects of flocculation. Canadian Mineral Processors. Paper presented in January, Ottawa, Canada. Helmstaedt, H.H. (1995). Natural diamond occurrences and tectonic setting of'primary' diamond deposits. Geological Association of Canada, February 6, 1995, Short Course 20, Vancouver B.C. Helmstaedt, H.H., Gurney, J.J. (1995a). Geotectonic controls of primary diamond deposits: implication for area selection. Diamond Exploration, into the 21st Century. (Ed.) Griffin, W.L., Journal of Geochemical Exploration, Vol. 53, Nos. 1-3, March 1995: 125-144. 101 Helmstaedt, H.H., Gurney, J.J. (1995b). Kirnberlites-why, when, and where? A hierarchy of geotectonic controls. Extended Abstracts, Sixth International Kirnberhte Conference. Russia 1995. Hem, J.D. (1992). Study and interpretation of the chemical characteristics of natural waters. USGS Supply Paper 2254: 263 pp. Hodgson, M., Dudeney, A.W.L. (1988). Hydrothermal alteration of kimberhte in acid media with aluminium ion additions. Trans. Instution of Mining and Metallurgy, Vol. 97, March: Section C: C1-C12. Holdren, G R , Berner, RA. (1979). Mechanism of feldspar weathering: Experimental studies. Geochemica et Cosmochimica Acta 43: 1161-1171. Hurlbut, C. S. Jr, Klein, C. (1977). Manual of Mineralogy 19th Ed. Wiley. Kirkley, M.B., Gurney, J.J., Levinson, A.A. (1991). Age, origin, and emplacement of diamonds: Scientific advances in the last decade. Gems and Gemmology. Spring 1991: 2-25. Levinson, A.A., Gurney, J.J., Kirkley, M.B. (1992). Diamond sources and production: past, present and future. Gems and Gemmology. Winter 1992: 234-253. Luce, R.W., Bartlett, RW., Parks, G.A. (1972). Dissolution kinetics of magnesium silicates. Geochemica et Cosmochimica Acta 36: 35-50. Mackenzie, J.M.W., LovelL V.M. (1971). The electric double layer properties of kimberhte suspensions. Nat.Inst. for Metallurgy. Report No. 1372:.31 pp. Mackenzie, J.M.W., LovelL V.M. (1972). The coagulation and flocculation of suspensions of kimberhte. Nat. Inst, for Metallurgy. Report No. 1403: 40 pp. 102 Macnae, J. (1995). Application of geophysics for the detection and exploration of kimberhte and lamproites. Diamond Exploration: into the 21st Century. (Ed.) Griffin, W.L., Journal of Geochemical Exploration, Vol 53, No. 1-3, March 1995: 213-244. Manahan, S.E. (1991). Environmental Chemistry. 5th ed. Lewis Publishers Inc. Mitchell, R.H. (1986). Kimberhtes: mineralogy, geochemistry and petrology. Plenum Press, New York. Mitchell, R.H. (1991). Kimberhtes and Lamproites: Primary sources of diamond. Geoscience Canada., 18: 1-16. Mitchell, R.H. (1995). The role of petrography and hthogeochemistry in exploration for diamondiferous rocks. Diamond Exploration: into the 21st Century. (Ed.) Griffin, W.L., Journal of Geochemical Exploration, Vol 53, No. 1-3, March 1995: 339-350. Milashev, V.A. (1963). Parageneses of secondary minerals in kimberhtes. GeoMrimiya (Geochemistry). No. 6:557-565. Moody, J.B. (1976). An experimental study on the serpentinization of iron-bearing olivines. Canadian Mineralogist, Vol.14: 462-478. Moss, N , Dymond, B. (1987). Flocculation: theory and application. Allied Colloids internal publication. Nixon, P.H. (1995). The morphology and nature of primary diamondiferous occurrences. Diamond Exploration: into the 21st Century. (Ed.) Griffin, W.L., Journal of Geochemical Exploration, Vol 53, Nos. 1-3, March 1995: 41-72. NWT Diamonds Project. (1996). Environmental Impact Statement. O'Gorman, J.V., Kitchener, J.A. (1974). The flocculation and de-watering of Idmberlite clay slimes. International Journal of Mineral Processing Vol. 1: 33-49. 103 Rescan (1995). Drill Chip Underwater Disposal Testwork Program. Report for BHP Diamonds Inc. (January). Schott, J., Berner, RA. (1985). Dissolution mechanisms of pyroxene and olivine during weathering. Chemistry of Weathering, (Ed.) Drever, J.J.: 35-53. Schuiling, RD. , van Herk, J., Pietersen, H.S. (1986). A potential process for the neutralisation of industrial waste acids by reaction with olivine. Geologic Mijnbouw 65: 243-246. Shaw, D.J. (1966). Introduction to colloid and surface chemistry. Butterworth Publishers. pp:186. Stumm, W., Wollast, R (1990). Coordination chemistry of weathering; kinetics of the surface controlled dissolution of oxide minerals. Rev. Geophys. 28: 2123-2135. Skinner, E.M.W., Clement, C R (1979). Mineral classification of S.A. kimberhtes. Kimberhtes, Diatremes and Diamonds Vol I. (Eds.) Boyd, F.R, Meyer, H.O.A. 2nd International Kimberhte Conference (1977). American Geophysical Union: 129-139. Sverdrup, H.U. (1990). Kinetics of base cation release due to chemical; weathering. Lund University Press, Lund. pp:246. Sverdrup, H.U., Warfvinge, P. (1988). Weathering of primary silicate minerals in natural soil environments in relation to a chemical weathering model. Water Air Soil Poll. 38. 387-408. Van Herk, J., Pietersen, RD. (1989). Neutralisation of industrial waste acids with olivine-the dissolution of forsteritic olivine at 40-70 °C. Chemical Geology, 76:341-352. Wilson, M. (1988). Igneous Petrogenesis. Oxford University Press. Wogehus, RA. , Walther, J.V. (1992). Olivine dissolution kinetics at near surface conditions. Chemical Geology, 97: 101-112. 104 Zinchuk, N.N. (1992). Comparative characteristics of weathering crust composition of kimberhte rocks in the Siberian and East-European platforms. Geologiya-i-Geofizika. Vol. 33, No. 7: 82-90. Zinchuk, N.N., Kotel'nikov, D.D., Sokolov, V.N., (1982). Variation in the mineral composition and structural features of the kimberhtes of the Yakutiya during weathering. Geologiya-i-Geofizika. Vol. 23, No. 2: 42-52. 105 A P P E N D I X A Mineralogical Analysis • Hand sample descriptions • Thin section descriptions • X-ray Diffraction plots 106 Sample: HPGR Panda Lithology: unknown Hand Sample Description: Fine to coarse grained, yellow-green in colour. Observed pale yellow, 1-2 mm olivine crystals (70%), red 1-2 mm garnet (5%), apple green coloured, 1-2 mm diopside (1%). Dark coloured, unknown minerals +/- magnetic (25%). No fizz with HC1. Thin Section Description: Anhedral crystals of olivine, garnet, diopside, phlogopite comprise 80% of slide. Few alteration minerals observed. Dark-brown fragments of rock (unknown mineral composition) containing non-fragmented crystals of olivine, comprises 10% of slide. (Plates A- l,A-2, Figure A-1). Major Minerals % Minor Minerals olivine 65 serpentine garnet 5 chlorite diopside 2-3 calcite phlogopite 1-2 quartz unknown dark mineral 3-4 107 Plate A-2:Cross polarized light view of above plate A - l . Olivine (bright colours, pinks and blues), garnet (dark), diopside remains green. 108 ^ I N — O-H S3 S3 0") JO O CO D •—> •—1 ix,<E<E ITJOQ 5'-<Q 6 9 * S 9 S 0 0 ' 0 J 00 "008 J l _ 0 0 ' 0 Figure A - l : Siemens 5000 x-ray diffraction pattern, (-75 um) of HPGR Panda. 109 Sample: Panda 1 (PUC 2-4, 914-13.7 m) Lithology: Heterolithic tuffisitic kimberlite breccia (TKB) Hand Sample Description: (Composite sample) Sample 1) Fine to coarse grained, heterolithic, matrix supported (40%). Pale green-grey colour, speckled with white and pale green minerals. Breaks easily, soft. Xenohths comprise 5% of rock, and resemble elongate mudstone clasts (1 cm). Observe olivine, serpentine, garnet and diopside. Moderate fizz with HC1. Sample 2) Similar to above, except matrix comprises 60% of rock. Clast much coarser (5 mm). Observe olivine crystal being replaced by serpentine (Plate A-3). Thin Section Description: Unidentified dark coloured alteration and/ or matrix minerals comprise 60% of slide. Anhedral olivine crystals and a fine grained white felted like mineral (possibly montmorillonite) comprise rest of slide. Most olivine crystals show alteration to serpentine along fracture surfaces (Plate A-4, Figure A-2). Major Minerals % Minor Minerals olivine 20 plagioclase garnet 2 chlorite serpentine 5-7 calcite montmorillonite 5-7 phlogopite unknown dark mineral 60 110 Plate A-3: Panda 1 core sample. Plate A-4: Plain polarized view of Panda 1. Olivine (clear) showing signs of replacement possibly by serpentine along fractures (2cm=lmm). I l l ^ 30'0i6 Figure A-2: Siemens 5000 x-ray diffraction pattern, (-75 um) of Panda 1. 112 Sample: Panda 2 (PUC 2-4, 20.7-25.6 m) Lithology: Heterolithic tuffisitic kimberlite breccia (TKB) Hand Sample Description: (Composite sample) Sample 1) Fine to coarse grained, light green-grey colour, clast supported. Heterolithic, similar to Panda 1 with respect to type and % of foreign clasts present. Contains rounded xenohths of granitic rock (1 cm). Matrix comprise 30 % of rock, xenohths 60 % and pale yellow-green crystalline olivine 10 %. Sample 2) Very fine grained black rock with minor laminations (mudstone). Contains (20 %) rounded, unitentified weathered mineral (8 mm) (possibly serpentinized olivine) (Plate Moderate fizz with HC1. Thin Section Description: Dark coloured unidentified minerals) and rock fragments comprise 30 % of shde. Observe olivines being replace by serpentine along fractures. A-5). Major Minerals % Minor Minerals olivine serpentine montmorillonite chlorite unknown dark mineral(s) 35 25 10 20 5 quartz plaigioclase calcite pyroxene phlogopite (possibly biotite) 113 Plate A-5: Panda 2 composite core sample Plate A-6: Plain polarized view of Panda 2. Olivine (clear) showing replacement along fractures to serpentine, phlogopite (yellow-brown, centre), rock fragment or unidentified matrix minerals) (bottom right) (2cm-1mm). 114 4 —A CD 0 3 I N 0 •cr CM o r 63 g CN " .-L-: CT' C3 - S - - .— rrr* 3 CD H. \f> on -£, - -CO DJ \D O — S3 0~> I N . &U1 Q - 0 • d.x csr-r - l 3 K S • r H . ^ a CU: o CO X r < <r Q ":; CD £3'S9b s^ u n o o g g - g Figure A-3: Siemens 5000 x-ray cliffraction pattern, (-75 u) of Panda 2. o IB Q ; J ;X —1 - — r j • CO r. « O 1 iT> Oil • CSS ! I • Q m 115 Sample: Panda 3 (PUC 2-4, 25.6 - 38.1 m) Lithology: Tuffisitic kimberlite (TK) Hand Sample Description: (Composite sample) Sample 1) Pale green grey coloured, medium to coarse grained, matrix supported. Similar to Panda 1. Observed olivines (alteration to serpentine), diopside (<1%) and garnet Sample 2) Very fine grained black rock, showing minor laminations (mudstone). Contains (5%) rounded, pale yellow minerals (possibly serpentinized olivine) (Plate A-7). Thin Section Description: Very dark slide, contains masses of unidentified black, angular clasts (xenoliths). Minor alteration to a very fine grained, white felted mineral (possibly montmorillonite) (Plate A-8, Figure A-4). (<!%)• No fizz with HC1. Major Minerals % Minor Minerals olivine serpentine chlorite montmorillonite Unknown dark mineral 2 5 10 10 70 plaigioclase phlogopite quartz muscovite calcite 116 Plate A-7: Panda 3 composite core sample Plate A-8: Plain polarized view of Panda 3. Observe the black unidentified rock fragments containing anhedral to euhedral grains of olivine (4cm=lmm). 117 IN j (3 r ° s .CO CO ** CO 69 to h£ (S 4 "-3 U 0? 1 0 +> r-0 X e-1 CO! CJ a, IN " CO "T K 0") a a.; o 3 X <E E-<Xi C i (X W to s LO a ^ 0 0 " Z c L £ 0 0 ' 0 a Figure A-4: Siemens 5000 x-ray diffraction pattern, (-75 um) of Panda 3. 118 Sample: Panda 4 (PUC 2-4, 65.3-70.4 m) Lithology: Heterolithic tuffisitic kimberhte breccia Hand Sample Description: Fine to coarse grained, heterolithic, matrix supported. Pale green-grey coloured, speckled with white and pale green minerals. Breaks easily, soft. Xenohths of mudstone, (1.5 cm clasts) and granitic rock (1.0 cm clasts) comprise 10% of rock. Observe anhedral olivine, garnet and diopside crystals (Plate A-9). Moderate fizz with HC1. Thin Section Description: Very dark shde, contains predominately masses of black, unidentified, angular clasts and yellow-brown blebs (serpentine and /or chlorite) (Plates A-10, Figure A-5). Major Minerals % Minor Minerals olivine 5 chlorite dark unknown mineral 70 plagioclase serpentine 20 garnet pyroxene quartz phlogopite ilmenite 119 Plate A - 9 : Panda 4 core sample. Plate A - 1 0 : Plain polarized view of Panda 4. Observe dark matrix (unknown mineralogy) fragments containing olivine crystals. Large olivine crystal in top right hand corner (2cm=lmm). 120 ^ 00'Z9E 63 r - r r G O o ui NO r- r-iD T 63 Q Qi i"! "63 O Figure A-5: Siemens 5000 x-ray diffraction pattern, (-75 um) of Panda 4. 121 Sample: HPGR Fox, Lithology: unknown Hand Sample Description: Fine to coarse grained, yellow-green, light grey colour. Observe yellow-green, coarse grained, anhedral olivine grains(60%), coarse grained red garnet (3%), coarse grained, apple green coloured diopside (1%). black flaky phlogopite/biotite (2%), unknown black mineral (35%)— slightly magnetic. No fizz with HC1. Thin Section Description: Anhedral crystals comprise 90% of slide. Little alteration of crystals observed other than the minor replacement of olivine by serpentine along fractures (Plates A-11, A-12, Figure A-6). Major Minerals % Minor Minerals olivine diopside garnet phlogopite/biotite pyroxene unknown dark mineral plagioclase serpentine 70 chlorite 3 calcite 5 2-3 2-3 5 2-3 2-3 (veinlets within olivine) 122 Plate A - l 1: Plain polarized view of HPGR Fox. Observe distribution of olivine (clear) with minor alteration along numerous fractures (2cm=lmm). Plate A-12: Cross polarized view ofPlate A - l l . Olivine (bright colours), plagioclase feldspars showing twinning (greys). 123 Figure A-6: Siemens 5000 x-ray diffraction pattern, (-75 um) of HPGR Fox. 124 Sample: Fox 1 (FUC 4-9, 31-31.4 m) Lithology: Heterolithic tuffisitic kimberhtic breccia (TKB) Hand Sample Description: Fine to coarse grained, pale green-grey coloured, speckled with white and pale green minerals. Heterolithic, matrix supported. Soapy feel. Inclusions of granitic xenohths comprise 5 % of rock. Observe yellow-brown alteration mineral (serpentine), rounded, white (altered) mineral (30%), red garnet (<1%), black metallic mineral (2%) (Plate A-13). Moderate fizz with HC1. Thin Section Description: Heavily altered slide. Unidentified alteration and/or matrix components comprise 80% of slide. A fine grained, brownish coloured felted mineral (possibly montmorillonite) makes of 50% of this material. Also observed are serpentine and chlorite psedomorphs after olivine. Observe unaltered grains of olivine, biotite, calcite. (Plate A-14, Figure A-7). Major Minerals % Minor Minerals olivine 5 plagioclase montmorillonite 45 hornblende serpentine 30 biotite/phlogopite unknown dark minerals 10 quartz v 125 Plate A-13: Fox 1 core sample. Plate A-14: Plain polarized view of Fox 1. Observe serpentine (yellow) rimming montmorillonite (brown) and chlorite (green) forming pseudomorphs after olivine (7.6cm=lmm). 126 h 00'Z86T-Figure A-7: Siemens 5000 x-ray diffr action pattern, (-75 urn) of Fox 1. 127 Sample: Fox 2 (FUC 4-6, 64 -64.7 m) Lithology: Heterolithic tuffisitic kimberhte breccia (TKB) Hand Sample Description: Similar to Fox 1. Fine to coarse grained, pale green-grey coloured, speckled with white, pale green minerals. Heterohthic, matrix supported. Soapy feel. Inclusions of granitic and black coloured (mudstone) xenohths/ xenocryst comprise 5% of the rock (Plate A-15). Minor fizz with HC1. Thin Section Description: Alteration and/or matrix components comprise 80% of slide. Predominant minerals are montmorillonite (white felted masses) and brownish-green fibrous serpentine and possible chlorite. Anhedral crystals of olivine, plagioclase and phlogopite observed (plate A-16, Figure A-8). Major Minerals % Minor Minerals montmorillonite 65 olivine serpentine 25 plagioclase dark unknown mineral 5 pyroxene chlorite quartz 128 Plate A-15: Fox 2 core sample. Plate A-16: Cross polarized view of Fox 2. Slide showing rock is heavily altered. Observe clumps of montmorillonite (white) and serpentine forming pseudomorphs after olivine (3.8cm=lmm). 129 *r cn cn I —> 1 LO (N > J 1 1: 1 o CO «T5 -*-> ID X. E-CO IN 0 rj- CO C Q N i-J 3 * CO .03 £ IN CS (M <S 13 .00 no CO CO 2 s o (N X fx, IN 9 <I cc X & "JM o Ji 19 ! O -<EO (3 ' LO +> • Q < •- u> n <E fO CO c a i i : o-.o 1 0 ^ LO I - i - -; t N < I I x • < O N ' (3 CO I O i --• m a*<X ^ -—<x — cotn - 07 T X or co 13 IS liifl a ^ 00'8Z8 00' 0 r CN co 3 L " CO i I I •3 I"I r-< Figure A-8: Siemens 5000 x-ray diffraction pattern, (-75 \im) of Fox 2. 130 Sample: Fox 3 (FUC 92-1, 45.7-106.7 m) Lithology: Heterolithic tuffisitic kimberhte (TK) Hand Sample Description: (Composite sample) Sample 1) Fine to medium grained, green-grey coloured, heterolithic, matrix supported. Breaks easily, soft. Xenohths of mudstone (8mm clasts) comprise 5 % of the rock. Observe yellowish-green, light green mineral (serpentine) (Plate A-17). Moderate fizz HC1. Sample 2) Very fine grained black rockwith minor laminations (mudstone). No fizz HC1. Thin Section Description: Alteration and/or matrix components comprise 60% of shde. Similar to Fox 1 & 2 as alteration is to serpentine and montmorillonite. Xenohths comprise 3 % of shde, generally shown as dark black unidentified masses. Observe anhedral crystals of olivine mostly altered to serpentine (Plate A-18, Figure A-9). Major Minerals % Minor Minerals montmorillonite 35 serpentine 25 olivine 5 chlorite 1-2 dark unknown minerals 3 0 quartz biotite pyroxene plagioclase 131 Plate A-17: Fox 3 core sample. I i i CO CN cn IS M LO ~ * 0 0 <r •I cn (T. © IN O m LO w rH u tN — J N •J I! H - X u c CO (S T5 s - » CN Q N . p H - ' 0 " CD - X O H c cn «D OS 00 CO "1 -- LO +> CO CO r H © O CO X cC >i o cs r H vi-CC CO X • u • • t n t c o i £ • ' co •' H-> J - * • C 2 + 1 : 0 " e I X <c ! E-) ( i O T C O 1 co I o S C r H :0 *0 •CN 0~ i ~ L 0 I X X ' ' t u r n T —« IN <I X " LO •ox • O (N 1(3 w -i I N CS CO CD X X X P re a co 00 ' to r-UD 00' 0 s LO n X X r H . — oi _ i CO —« <I L0 , r ~ w • ) X CO CD X ' i3 IN CD 107 CT. CO 07 T CO : S 3 < S ! i I • r - iS rH <HrH Figure A-9: Siemens 5000 x-ray d"ifrraction pattern, (-75 um) of Fox 3. 133 Sample: HPGR Misery Lithology: unknown Hand Sample Description: Fine to coarse grained pale grey-green colour. Observe numerous 1mm red and orange garnet and 1mm olivine crystals. Also phlogopite, muscovite and diopside. Minor fizz with HC1. Thin Section Description: Anhedral crystals of olivine, garnet, calcite, diopside and phlogopite comprise 80% of the shde. Minor alteration of olivine to serpentine observed (Plate A-19, Figure A-10). Major Minerals % Minor Minerals olivine 55 chlorite garnet 10 diopside calcite 7-10 montmorillonite phlogopite 3-5 serpentine 134 Plate A-18: Plain polarized view of HPGR Misery. Notice the abundance of anhedral crystals. Olivine (clear), diopside (green), garnet (pink). Minor serpentine (brownish masses) (2.0cm=lmm). 135 ea ' 0 Figure A-10: Siemens 5000 x-ray dif&action pattern, (-75 um) of HPGR Misery. 136 Sample: Misery 1 (MCH 3, 304-306.9 m) Lithology: HeterolitMc tuffisitic kimberlite (TK) Hand Sample Description: Black very fine grained, matrix supported. Sample very friable. Observe large crystal of muscovite (5mm) and clasts of mudstone (possibly an altered mineral). Also olivine crystals, garnet and diopside (Plate A-20). No fizz with HC1. Thin Section Description: Alteration and/or matrix components comprise 80% of slide. Predominant minerals present are montmorillonite and serpentine. Observe pseudomorphs of montmorillonite and serpentine after olivine. Unaltered crystals of olivine and calcite also observed (Plate A-21,FigureA-ll). Major Minerals % Minor Minerals montmorillonite 50 serpentine 20 calcite 10 unknown dark mineral 10 olivine chlorite phlogopite 137 Plate A-20: Misery 1 core sample. Plate A-21: Cross polarized view of Misery 1. Observe montmorillonite (white) and serpentine (yellow-brown) forming pseudomorphs after olivine (7.6cm=lmm). 138 ^ 00"8901 00' 0 ) vJj CO T I " H <T LD T : S Q 63 r - l ( i l l r • G UTT • i cH rj< Figure A - l l : Siemens 5000 x-ray (uffiaction pattern, (-75 um) of Misery 1. 139 Sample: Misery 2 (MCH 3, 332-335 m) Lithology: Heterolitliic tuffisitic kimberlite breccia (TKB) Hand Sample Description: (Composite sample) Sample 1) Fine grained, friable, pale green-grey colour, matrix supported. Numerous "soft" white, pale yellow in colour, mineral fragments (altered olivine?). Note olivine crystal in altered mineral. Large granitic xenolith (1.5 cm). Minor fizz with HC1.. Sample 2) Very fine grained, grey-black in colour, soft, matrix supported. Few, pale-yellow, soft, rounded altered minerals. White coating on fracture surface. No fizz with HC1 (Plate A-22). Thin Section Description: Dark coloured alteration and/or matrix components comprise 75% of shde. Minerals observed are montmorillonite and serpentine (very similar to Misery 1). Abundant calcite observed. Major Minerals % Minor Minerals montmorillonite 60 chlorite serpentine 15 olivine calcite 8-10 garnet opaque 5 phlogopite 3 140 Plate A-22: Misery 2 core sample. Mineralogy and texture very similar to Misery 1. 141 cn cn CH i w—t 3 •-9 I LO CN J 5^  1 s S I N si: 4 J « 0 CO 1 #» h E -I r", 0 0 ' £ J 9 CO CM 0 <r <sr cn M g LO CN -CD CO CO 7 !LO CO O C N 0 -._}<3L - S O L (S 0 E E - L O ^ •P M"I • O C I r H < £ o » cn - v - CS — jrf 3 CuXLO CN _^ 2.' X K : (S • r» (N (-3 X O w CN cn o c w o X CD X X E-* X o (X Cd CO X (3 s Q LO P 0) • - H-> 00' 0 CJ - - o o -CON I - - ' —ro - OT CO o ;t X cn <C - S E O I: — X r N r~ <>D H CT. v T CD - LO 3 s n o ; I 1 I X Figure A-12: Siemens 5000 x-ray diffraction pattern, (-75 um) of Misery 2. 142 Sample: HPGR Koala Lithology: Hand Sample Description: Fine to coarse grained, mottled green-grey colour. Observe yellow-green coloured olivine, red garnet, biotite and or phlogopite, muscovite plagioclase, and diopside. Minor fizz with HC1. Thin Section Description: Anhedral crystals make up 80 % of slide. The rest of the slide is comprised of a very fine grained, green coloured mineral (chlorite). Few olivines show alteration to serpentine. Observe a wood fragment infilled with calcite (Plates A-23, A-24, Figure A-13). Major Minerals % Minor Minerals olivine 70 calcite garnet 7 montmorillonite diopside 2 plagioclase clinochlore 5 biotite dark unknown minerals 13 143 Plate A-23: Plain, polarized view of HPGR Koala. Slide comprised of fragmented crystals of olivine (clear) garnet (pinkish colour, right side), phlogopite (slender green mineral center). Calcite (fine grained, brownish). Note wood fragment (bottom center) (7.6cm=lmm). Plate A-21: Cross polarized view of Plate A-20. (7.6cm=lmm). 144 0 <r cn C3 IB C c CH 03 I u o <r cn ID ^ 00'IZS O O J -• LJ" CNCD c o---vf t-i - 1 csi—<r o ai^r-'CriTj m o r s » T CH l J CVHODLf) ii) N 1 - • /-» -rn; S J - • I-H t, x 0 : 0 0 I C - H I W w x i/pH "HUT? IS <X ; - « C ( K-•••••> I »—' J i ^ - -• O :.<E «--< X CH^-° 0 - -fl I Hi (S CD j r-C;C0 »<£ »3C W O *•»-*» I C <U — 03 -> CD CDO<E nJ—• — — ->0<E COCO <D CD w w {Tf •-• CD cn » O C 0 * z: Ml * X O " U I > Q * X 01 <vT CD <.£> 03 CD LO IS- CO CD <T v,C C3 0100 (3 63QC33C3 I I I I 1 (3v-» r- U» K» Figure A-13: Siemens 5000 x-ray attraction pattern, (-75 um) of HPGR Koala. 145 Sample: Koala 1 (92-10, 157-178 m) Lithology: Heterolithic tuffisitic kimberhte (TK) Hand Sample Description: Fine to coarse grained, pale green-grey coloured, speckled white and pale green. Heterolithic, clast supported. Friable with numerous inclusions of black mudstone like xenoliths which comprises 5 % of the rock. Few mineral clast are highly altered to a clay like texture. Observe small grains of phlogopite, garnet and olivine (Plate A-25). No fizz with HC1. Thin Section Description: Very fine grained alteration and/or matrix components comprise 60% of the slide. Predominant minerals observed are serpentine, chlorite, olivine, plagioclase, phlogopite and quartz (Plate A-26, Figure A-14). Major Minerals % Minor Minerals olivine 10 montmorillonite Quartz 3-5 phlogopite/biotite serpentine 2 plagioclase clinochlore 7 dark unknown mineral 50 146 Plate A-25: Koala 1 core sample. Plate A-26: Plain polarized view of Koala 1 showing the abundance of dark unknown masses. Crystals of olivine garnet, and phlogopite also observed (2cm=lmm). 147 rH i D cn cn I I I I LO CN 3 j 4^  o CO ra +> OJ I CO CN vO CN 0 <E rf CO M eg L.7 CN •-IN J CD C3 S CN s CN is CS -CD 07 CO CO 3S) - LO J 0 3 < T . w-tn IS -H'LO — o - x c n c ^ <s 0 T SE- 'LD s^.unoQ 00* 0 jC H"~' 01 ' U C 1 rH o 0 C B C ^~ -P - -rH • ~ rH — O 0 . 3 "J I N 0 w X X cn :o a o ID CN 2 rH 3 -, . — p J " CN JX X O--0-. U - X 0 X O [N co X rH w •—• - - H PC b ~ i x •+> cs • vT rH O C rH rH -• o w <r J -"3*63 X Z — rH rj< - CO O ^ O , , N ~ x X i i - _ 0 CD X - ' c o X ~ I S . COLO c E- - — CO CN X x —* Q " - - 0 7 CD coX cofO i. >r?X co CO X X I X y cs s r -LO : CN <r Q 2 'X CS rH y M i l n N X <J< o •H rH H r f Figure A-14: Siemens 5000 x-ray diffraction pattern, (-75 um) of Koala 1. 148 Sample: Koala 2 (92-10, 332-335 m) Lithology: Heterolithic tuffisitic kimberhte (TK) Hand Sample Description: Similar to Koala 1. Fine to coarse grained, pale green-grey coloured, speckled white and pale green. Heterolithic, clast supported. Friable with numerous inclusions of black mudstone like xenohths which comprises 5 % of the rock. Few mineral clast are highly altered to a clay like texture. Observe small crystals of phlogopite, garnet and olivine (Plate A-25) (Plate A-27). Minor fizz with HC1. Thin Section Description: Very fine grained alteration and/or matrix components comprise 80% of the shde. Predominant minerals observed are serpentine, chlorite, olivine, plagioclase, phlogopite and quartz (Plate A-28, Figure A-15). Major Minerals % Minor Minerals olivine 30 plagioclase clinochlore 5 phlogopite dark unknown minerals 60 calcite diopside montmorillonite serpentine 149 Plate A-27: Koala 2 core sample. Plate A-28: Plain polarized view of Koala 2. Note masses of dark opaque minerals, abundant chlorite (pale green), and olivine (clear) (2.0cm=lmm). 150 I 5 "5 4 1 s \ ^ 00'0S9 s^unoo Figure A-15: Siemens 5000 x-ray diffraction pattern, (-75 um) of Koala 2 co G CTi CN N, Ll 3 0 a: <j* cn " N m LT3 sr l - -0 •TS CN - - ..-r CNJ 3 S co n's -iii p4 CO 63 "I CN C3 N - ' 63 — <E ' j ucn Q O S CO —< \ f CO X CO <— Q CO l > -1 co r, o -O X — ! E-.C ©CO I O 0 - o> i ^ -IN — — CL J C< O X O co x CO tN O (si a -• x — i-i 3 X X X X O ' P~ 3 - ~ IN <E r-i x PC O O X \L Q • w o /r ** CN - ca w •* l J - - C N 6 3 x - C O O o -\-CD X w < X X / .n — n-i <T rn —• E-* — — CO <r <i ^ w o -—ro L i j i K m<E co CO - X X —1 K»00 ® iN 63 CO CO CT) £ If) «H CO T C' Q 6363 63 _y / i n 00'0 o f'"S 151 Sample: Leslie HPGR Lithology: Hypabyssal Hand Sample Description: Fine to medium grained, grey in colour. Mineral fragments are grey, no texture, not easily determined. Minor fizz with HC1. Thin Section Description: Fragmented olivines, and possibly monticelhte, and calcite comprise 50 % of shde. Other half of shde comprised of a dark coloured, non-descript matrix, some may contain small crystals of olivine. Some serpentine observed (Plate 30, Figure A-16). Major Minerals % Minor Minerals olivine 20 diopside monticelhte 20 garnet calcite 3-5 phlogopite opaque 40 serpentine 152 Plate A-30: Cross polarized view of Plate A-29. Olivine is the colourful fragments (7.6cm=lmm). 153 f!j 00" E9v JL 00*0 x .IN I *T CO X Sea I X X 00 '£9- f s3.1j.n03 00'0 ro e-. x Q K W T CO ro x , / o o HI IN tO CO o a cn X T - LO 0 • x on cnx ^ cs cn - - o . " X J> -L0^C3 rf • rj< nrto _3 - - v-i •w 3 +> - • nm t x +'C0 w "•-<-< 31 CD J ) - * (ft — C «-»— -p C O 4)<E f-> +> —• "sT CO M C O A +> C O J I -X L O 0 tr LO * 70N0U O " M - i COX — CO CO roOCOO •"•:-X-- COX •ST; rtS CD CD t j E O I E O co cn cn •> <x) •XuNfOrHQj t- r-t c\i T LO 3 G S G Q M i l l x <r* r- r> ui Figure A-16: Siemens 5000 x-ray diffraction pattern, (-75 um) of HPGR Leslie. 154 Sample: Leslie 1 (LDC 13, 68.6 m) Lithology: Heterolithic kimberhte breccia (KB), Hypabyssal Hand Sample Description: Very hard, competent rock. Pale grey colour, matrix supported. Contains dunite xenolith (3 cm), olivine crystals (4 mm), diopside and garnet (Plate A-31). Fizz with HC1. Thin Section Description: Fragmented crystals comprise 60% of slide. Rounded crystals of olivine and monticelhte and, rhombic crystals of calcite are observed. Rock fragments are generally a black-brown matrix supporting rounded crystals of olivine (Plates A-32, 33, 34 and 35, Figure A-17). Major Minerals % Minor Minerals olivine 20 serpentine calcite 15 diopside garnet 5 (few show kelphatic rims) phlogopite monticelhte 15 dark unknown masses 40 155 Plate A-31: Leslie 1 core sample. 156 Plate A-33: Cross polarized view of Plate A-32. Olivine, possible monticellite (coloured mineral), calcite (bright) in lower left corner, pervoskite top left corner (orange) (2cm=lmm). 157 Plate A-34: Plain polarized view of rock fragment detail. Garnet (left side with kelphatic rim), olivine, large crystal in center showing alteration to possible serpentine, calcite rhomb in top left corner (3.8cm=lmm). Plate A-35: Close up of Plate 34, cross polarized view showing garnet (dark), kelphatic rim (orange-brown), and olivine colored (7.6cm=lmm). 158 1 1 "I 1 7 — r' } 1 f • -I i i — !—~~ Sii : \\ i }. -- 1 y : • { -f C i 1 1 , V CM —< IS •r-cn r-LD L .CD (NJ 1 G3 LLO , N CM •S 60 L £ CO N CO •. _1_ JL. cn CM <r [ N . CO LO CO o CM CM CO -2 :>» CMg •'X tt CO J D X 1 E- 1 I CD CC w CO n 6 3 Q L O ft ^ 0S"08Z sq.unoo 00' 0 0S'08Z sq.unoQ 00'0 c <r cn is L O 0 - X 0 <H cn <L - 63 (Ji 0 " - • • T o<r O J L O srcn<r.:i -L O 6 3 CT) w - •^63 - r-> L O \T E - • -0 ' LO 03 J 'I - • H - I X j , j d m •-T*-* J Q3 -o U J CUH-H 3 w c o C e a oo •v C — — -3 —« 3 > £ -2 0 L. « CL •-> 0 C, c o - C M 0 C — — © - £ T l _ l +> X IA §3 C "** O P -—< © C S X © + » T + * H •* B O CM ox u•-U X O 0 ~ I - &, <L O S T L O CD J O O <T i D - C M O C 0 O n co — —• ^ CM c o C Q € M O — ' J ' X C O C M c r i C O 95 c o co i_ —< : O I E I X ) s r- co CM r-1 •vT vfj on CD i CM r-1 CD >©r+©<SCS 1 I I I I S Q W ^ C S f M Figure A-17: Siemens 5000 x-ray diffraction pattern, (-75um) of Leslie 1. 159 Common Kimberlite Minerals Mineral Chemical Formula Features Olivine (forsterite) Mg 2Si0 4 strong bifringence Phlogopite KMg3Al(OH)Si04 crystal form, brown colour Diopside CaMg(Si03)2 cleavage, green colour Garnet (pyrope) M g 3Al 2(Si0 4) 3 isotropic Calcite CaC0 3 strong bifringence, crystals Monticelhte CaMgSi04 Brucite Mg(OH)2 Pervoskite CaTi03 colour, tvvinning Serpentine Mg3Si205(OH)4 colour, form, occurrence Apatite Ca5(P04)3(F,CLOH) crystal form JJmenite FeTi03 opaque, crystal form Spinel MgAl 20 4 crystal form, isotropic Chromite FeCr 20 4 opaque Enstatite MgSi03 pyroxene form, cleavage Mineral Other common n ^ Chemical Formula Features Quartz Plagioclase Chlorite Muscovite Talc Montmorillonite Si02 NaAlSi308-CaAl2Si208 (Mg,Fe)3(SLAl)4O10(OH)2 (Mg,Fe)3(OH)6 KAl2(OH)2(AlSi3O10) Mg3(OH)2(Si08)2 (ALMg)8(Si401o)3(OH)1o 12(H20) FeS2 no cleavage, lacks alteration twinning colour, pleochroic,cleavage form, strong bifringence as above rricrocrystalline aggregates 160 APPENDIX B Chemical and leach test results • X-ray flouresence of whole rock and -200 mesh fraction • pH leach test results • Pre and post leach X-ray flouresence analysis • Olivine dissolution test • X-ray diffraction plot for olivine dissolution test • particle size analysis for the olivine dissolution test 161 > i5 o o cj o o o pq O PH o o u '3 o o cs o g CD 00 M in ^ O '— M I S CN r-H r H vo vo r- vo ON o r f ON N i f l h i £ ) « 1 CN ^ r-H <—1 r-H ON r f in r f 00 oo r f m o\ 00 <N ^ r-H r f r~ t"- CN r f vo o r- p p T-H ro os o o ON in r f o in 00 VO >n ON r f I—" O C O 00 r-H O r~ VO r f 00 r f CO CN ON in >-H o cn m oo O ON r f r f O CN VO O N vo 00 r f O cn CN r f CN vo r-CN CO CO r f co r-~ O r-H O r-H IT! CN r-H CN t--CN C O r f r - H CN r f in r-H r f O O O O O h h CN in co O 00 vo in o o o o o vo in o CN in o C O o r-H O o o o o o vo 00 CN CO t~- r f ON C O r-H CN r-H r f CN f O CO O m CO in r f CN O r f r f CO CO t~ CO r-H r f r-n' 00 C O C O oo oo r~ oo oo o o o o o ON O VO >n r-n ON m in vq co O CO r-H r—I ON r - H r f O NO r f t— CN in ON i> CN vo vd in <-H ON O in 00 vo r-H O (N r f vo O r-n O O O CO CO 'rf t O r-H r-H CO O O O CN o oo o r f r f r f CO CO •a X o PH ° IS ' - H o cu i4 & & eg o o o o o & & & & PJ HH HH HH HH HH t ^ O N C O O N O N O N r f c O i n C D O N O O O O r f C N v o i n o O N O v o o o o o r f i n v o o o c N o o c o m r -CN r— r-H r^  r^  c—in CN CN vo ro m oo r~ vo CN r-H r-H r-H r-H r-H ON r~ o CN 00 r-H m CN O O CN C O CN r-H i—i r-H r-H o in CN in co ON r f in o o o o o co in r-n o <n r-I O CO r f r-r-H r-< O r f r f r f VO CO vo CN r—i ON r-H r-H r-H fN CN r - 1 o r f O O O CN r f ON CN ON O ON r- o i n c o o v O N r f O N r f r - H i n i n oo cs O r f r f r-H vo in 00 00 00 t~~ r-H CS VO m 00 in r-H r—I o CO in vo r f CN vo r-n ro vo vo CN r f CN t in oo CN o r f r- oo CN r-VO r-H r-H r-H r-H f— CN O N O O v O r f O O O O C - r - n O O r f i - H C N C O O r ~ r - - - O N C N r f i n r f r - H t~-c-~coONinoocotN>nvovoo r - r f O O O O C O r - ^ r - H r-H r-H VO 00 CN 00 V O O r f C N V O O O N C N V O r- C O r-H O ro 1—1 r-H o ,_ ,_ c- ro C O r- ON O N r-C N in o 00 o 00 in in in O N r f C N C O o o O N r-H ,_, o m m r f o p r ^ <—1 r—I vo in C N m m ON O N o ,_ V O O C N r—< p r f in C O r f O in cn in r f 00 t - O N r f r f in 00 vo C N 1—1 r — ' r-H 1—1 C O CN r f in ON o r-H CN r f O N -H O o o o o r f O CN CO vo O N o m O N O N o r-H CN r- CO m r- in CO r- 00 *—i CO in CN o cs o 00 o 00 ON CO O N CN CN in 00 VO r-H vo r- VO ,_ r-H r- r--CN CO CS CN cs CN CN ' — 1 *— 1 r f d d d d d d d d d d O r f CN VO vO CS r f r f m ON r f CN CN O in CO r-in CO in O 00 r-oo in in ON o in CO 00 cs VO d d d d d r f '-' CN CN d d d m o 00 00 CN O vo r-H o O o 00 cs ON O r f vq 00 in m rH t--o r f o m o d d d d d d d d d r ~ ' d d d d d d o CO CO p oo vo 00 ON r f O vo vq ON 00 CN CO o CO cs ON ON r f cs 00 vo cs 00 r f r-H r-H vo o in CN CO d CO CN cs in r f r f in in CN m cs r—1 CO CS VO CN r- VO vq in in r f CN r f VO in 00 00 o CN CO CO CN CO r f VO CS 00 m cs o CS r f ON CS r f CO CO 00 CO CS CS ON r-H r f vd CN CO cs 00 vd CN CS vd CN in CN d CS r f CO r- 00 VO r-H vo 00 I—1 r-o o o r-H o ON O ON o t-d d d d d d d d d d d d d d d d d CO r-00 t> CN 00 in CN in p CN CN ON CO p p in 00 in vq CO CO ON 00 CO r f ON ON o ON CN ON d ON r-' ON vd r-' vd vd vd vd in ON in CO VO 00 cs ON 00 r f m r-r- r f CN O CO 00 o 00 VO VO r f vq 00 00 in o. VO CO CO cs VO <n r f in r~- cs CO vd ON r- vd r f CO in CS r f O r f cs VO r f NO r f ON CO cs in cs CO CO 00 r f m r f in co CS CS CO CO 00 in d d d d d d d d d d d d d d d d o r f m vq CN o VO m r-in CO in vo r f in o r f CO p o ON r f vq o m r f CS ON d r f CS r f d r f 00 CO d CO vd r f 00 r f in r f r f CS r f vd r f 00 r f r-H r f ON CO d m d in ON CN T3 PH CU HJ r—I CS CO r f r ^ ^ r ^ r ^ P ^ e r J C S W C q & & P j P j P j c 1 c 1 § c i ^ H cs CTJ o CN o PH PH PH (4 r4 2 6 ^ O H a, S C M C H CS o d ex C H ^ C H in s C H in I co in N? i cs in N ? ON o CO O N ? I CN in CO o vo 162 pH Leach test results Sample pH Test Initial Final pH pH Initial wt Final wt lose solids(gm) solids (gm) % solution surface vol. (ml) area (m2/kg) HPGR Panda 7.00 9.00 11.00 8.04 8.35 8.04 9.03 8.05 10.74 993.70 975.60 1.82 989.20 950.60 3.90 979.80 967.00 1.31 1266.89 17.99 1078.23 18.19 1326.18 17.71 HPGR Fox 7.00 9.00 11.00 10.23 7.15 10.18 8.76 10.13 11.42 1077.60 1004.50 6.78 1000.00 968.60 3.14 1017.20 986.50 3.02 1890.60 13.18 1367.63 12.82 1263.21 11.71 HPGR Misery 7.00 9.00 11.00 8.41 7.40 8.41 8.45 8.40 10.15 997.30 966.40 3.10 1002.60 966.10 3.64 1033.40 1018.70 1.42 1524.67 11.43 1658.44 11.73 1969.42 11.06 HPGR Koala 7.00 9.00 11.00 8.56 7.64 8.40 9.05 8.35 10.76 1000.00 976.00 2.40 996.80 977.10 1.98 1003.20 966.90 3.62 1974.93 12.66 1992.41 12.96 2096.98 14.48 HPGR Leslie 7.00 9.00 11.00 10.46 8.06 10.44 9.16 10.22 11.31 1005.80 929.80 7.56 993.50 923.70 7.03 1067.50 997.70 6.54 3050.43 15.40 2069.56 15.40 1608.66 15.40 Sample mg/1 Mg Al Si K Ca Fe Total Total mg/kg mg/m2 HPGR Panda 160.00 0.00 9.69 20.40 90.80 0.01 123.00 0.00 5.18 22.40 52.10 0.01 2.67 0.00 3.14 11.00 2.58 0.01 358.13 19.91 220.93 12.15 26.26 1.48 HPGR Fox 78.10 4.00 49.80 96.50 260.00 0.01 5.67 0.02 12.80 63.90 22.80 0.01 26.20 5.32 56.50 32.80 5.89 0.01 856.89 65.01 143.87 11.22 157.37 13.44 HPGR Misery 252.00 0.00 12.00 54.10 363.00 0.01 81.20 0.00 5.49 47.40 49.60 0.01 3.39 0.01 1.40 16.40 2.70 0.01 1041.28 91.10 303.87 25.91 45.56 4.12 HPGR Koala 325.00 10.70 48.40 149.00 819.00 0.01 29.80 0.01 4.92 33.90 21.10 0.01 15.60 0.96 8.64 17.10 9.90 0.01 2670.32 210.93 179,36 13.84 109.13 7.54 HPGR Leslie 3440.00 0.00 10.20 197.00 1050.00 0.01 272.00 0.00 0.56 142.00 69.10 0.01 1.73 0.00 1.27 147.00 1.11 0.01 1.42E+4 925.06 1007.53 65.42 227.73 14.79 163 i5 o o o o o r I u o TO PQ O PM o is o O H O i ^ o o o c/5 c o CN in rt V O o T - H CN r--<N V O V O V O r-- N O O N O T t ON ( N V O r- V O in CN ON T t in T t 00 00 c o T t IT! O N 00 CN T - H T - H T t r- CN T t vq p r-- O p d d C O O N ON m T t o >n 00 V O 1/N ON T t d C O 00 o V O T t 00 T t co CN ON m 1 - 1 d C O m' 00 o ON T t rt in T t O CN CN T - H V O ON V O CN r-oo T t O CN C O T - H i n ( N T t rt rt CN V O r- t - c-CN C O co T t T—H CN T t C O r- T f in O H H o < - H T t d d d d d O N r- o 00 ( N >/-) c o V O in • p* 09 d d d d d V O in o C l o CN in o T - H o d d d d d GO H V O 00 CN ON C O co r- T t 1 CN 1—1 T t CN T t d T - H PH co O in r- C O C O m T t H H T t <N d T t H 00 T t C O C O C O C O 00 00 r~- 00 00 1—1 T - H '—i '—1 '—1 • d d d d d ON o V O ON in >n vq C O d C O — T - H O N T t o V O T t f N m ON r-CN VO* V O in O N O in 00 V O I—1 O CN T t V O d < 1 d d d in C O T t o *—1 C O o o d CN d 00 d T t T f T t C O C O -3 PH -2 " T O o p4 pi pi p4 o4 o o o o o & & & & H H H H H H H H H H T t ON C O T t 00 o C O T t CN C O T t C O r- in N O T t C O C O rt CN CN o CN rt CN CN CN in T t C O ,_ o o m CN rt 00 in 00 t - 00 ON C O r- C O O CN rt 00 C O CN CN CN T t T t T t r- in in V O t~-CN CN CN >n 00 CN in 00 r-- CN in V O 00 r~- T t T t V O C» o C O CN r- rt rt ON 00 O r — ' C O C O C O • — 1 CN CN CN CN o o O o o o o O O O o O m <n m o o o o 00 m ON 00 V O d d d d d d • - 1 CN CN CN CN CN V O ON in o o o o o o O N T t T t C O 00 00 in p O N r- vq CN CN in C O C O C O d d rt* 1—' c o C O T i 1—t d '. 00 V O CN o T t o 00 r- 00 00 O V O r- 00 00 o o o O N CN O N V O in O ~ d d d T t C O vd vd vd 00 T t T t CN T t in m C O 00 in O N r-H O N >n r- o o C- m C O o C O >n C O CN C O o 00 ON V O rt o in O N V O QN ON O N V O m in , — ' o o T t T t T t CN O o CN CN o T t 00 00 V O in C O CN CN in r—« CN m T t in r~ T - H C O CN CN CN T t T t T t CN T t T t t~- r-1-H , — ' m m m C O T t T t r~- o o T t T t T t o o o '—' '—' T - H O T ' T - H H H »—H rt d d d d d d d d d d d d l> O 00 i n T t O N CN i n m c o vo T t r-o T t o T t O N V O o v o o VO in in o. CN vq CN CN O CN CN CN d o r-CN i n ON i n o r~-CN V O T t T t ON m V O t -00 T t m T-H T t i n vo CN CN CN 00 o O i n T t m m C O d d d CN CN r - C 0 t ~ ~ 0 0 O C 0 C 0 C 0 T t ' - H O O N C N c N o o ^ r ~ c o i n i n v o v o v o > n T t c o o o o o o o o o o o o o o o o V O O p o d d v o v o T t > n o T t ' - H T t v o o N v o i n i n O v o t ~ - t ~ O O C N ' - H O C < - > p p p d d d d d d d d d d d d d C O in C O T t 00 00 00 V O O CN m T t in O N o 00 00 CN 00 o V O CN O N in ! — ' , — ' T t T t T t CN CN CN C O C O C O ^ rt T t vo m C O ON 00 C O >n C O V O m CN V O O N 00 o o T t C O T t ON V O r-O O N N O CN m ON 0 s -d . T t T t T t r-' CN 00 CN 00 CN T t C O d C O T-H C O d C O d C O d C O vd C O vd C O vd C O ON O N ON o CN O CN o CN 00 r- V O r-- 00 00 ON o CN o CN O C O N ? 0 s -d d d d d d d d d d d d d d d in o O N r-- ON CN vo T-H O N T t o C O rt T t o r- o CN 00 C O CN >n o vq O N O C O 0 s -CN rt in <n wo C O CN CN CN CN CN O N O N ON o 00 T t C O ON ON 00 00 vo o >n 00 ON ON 00 o o O N r- ON T t 00 O O N o CN °^ 0 s -CN CN CN V O vd vd vd vd vd in vd in r-H CN CN CN CN m ~~| "~| C O CN 00 CN 00 CN N O C O vo C O T t C O CN T t V O in C O ^° 0 s -d d d d d d d d d d d d in 00 in o in o ON in o ON in o C O V O 00 m vo m o vo 00 in C O CN o vo 0 s -ON C O d T t d T t T t CN T t T t d T t T t d T t ob C O C O r~-c o ON CN O N CN d C O _ _ > - H t ^ O ^ r t i - H H H t - O N - H ^ c ^ o . r t r - O N H H ffiffiffir-ON-WWWffiffiffiKffiffi ^ ^ J J . O H O H P H C H C H C H Q) (J) Q) w—I i—l i—H • i-H • ^-t -i-H OH OH 11 PM PM £ K K U) ^ a, a D . £ ^ c3 o o o PM PH PH PH 164 Olivine dissolution test unwash sample washed sample Hour pH Mg (mg/L) Hour pH Mg (mg/L) 0 9.4 16.8 (precipitate 0 6.2 53.8 3 9.3 5.4 form) 3 5.9 50.8 6 9.5 5 6 6.7 49.8 9 9.4 5.4 9 6.9 43 12 9.6 6 12 6.8 40.4 24 9.3 6.6 24 7.1 38 36 9.4 8.6 36 7.4 39.4 48 9.3 11.4 48 8.3 36.2 60 9.4 12.4 60 8.2 35.4 72 9.1 13.4 72 8.3 34.2 96 9.2 15.4 96 8.7 35.6 pH of distilled H 2 0 5.9 Weight of unwash sample: 10.001 gm Weight of washed sample: 8.046 gm Average particle size: 335 microns 165 CD "CO i t "1 2 f-o <r cn co CD IN CS CS CO ro CO 6 3 E-"' CO | CN 4 w — %_ 05 => r CM O K I U 00' 0 0 0 ' 6 £ S 00' 0 CN Q iC i" w co: 63 63 ; CN EJ 166 OLIVINE DISSOLUTION TEST Sample: O l i v i n e - l a Units: microns x v e P e r c e n t 0 f F e 1 u 100 75 50 25 l l I I 67.4 175 282 i i 496 i T 603 389 Avg Diameter i i i i i r 710 817 924 167 APPENDIX C Physical surface characteristics mcluding: • Cation exchange capacity calculations • Particle size distribution plots for Panda, Fox, Misery, Koala and Leslie • Surface area calculations for HPGR and core samples • Density summary • Zeta potential summary and graphs 168 d 0 • rH 1 13 o O w u ocB & O 00 u 8 a o o o W ID 60 § "8 'si 3 3 g o « -H t i l 13 .2 3 S 5 ^ H o w rf O ^ ^-rZ « M | H o CD O ON V O t-~ in CN t> CN cn O N o ON CN r -H in VO i - H m CN CO 0 0 © r - H ON co t> V O 00 V O v q O V O 0 0 <n in l > © in 00 d i—I CN Co' O N r f CO r f r - H r - H r -H r -H CN r -H CN r f V O CN CN r - H CO 0 0 CN r f VO r f 00 VO r f I -H CO CO CN CO m CN m d d d d d d d d <n CO CO CO in r f r f CO VO r f o o o o o O O o o © d d d d d d d d d O r f r f CO r f CO r f r f in m VO in CO ON o o r - CN VO CO r -00 r f r- o in in r - H CO 0 0 O N CN f - ON 00 r - r - H in O N r - H o v d d d d v d r f r f d r - H CO r - H r - H r - H r -H r - H r - H r - H * -H CN r - H ca CD ^ 2 « § ^ HJ P^ P^ P^ o o o o o & & & & & I W S M H a o PM PH O N co d I-H m o CN CN VO VO d d NO V O o o d d co co r-i-H CN CO CS ca ca d d d a a a r - H CN CO X X X! o o o PH PH PH r-H CN r V CD CU CO d oo d rf in o o d d ca ca 'w 13 CN 00 00 d CO o i-- CO CN oo o CO m r - CO CO r f 0 0 ON VO ON 0 0 v q CO O N O N r—I i n d r - H I - H i - H r - H r - H VO o r f r - H CN oo CN r f 0 0 CN T-t- VO VO VO r f r f d d r -H r—! d r - H CN d CN \ J CN CN CO d CO 00 r f CO r f m VO VO CO CO VO r f 00 ON in r f ON CN m r f O N r f CO . 0 0 vo r-~ #*r\ VO 00 CN m CN m CO O 0 0 r f VO O N CO /— \ VO © CO O r f ON CN in VO CN Ov i - H m in W CO m ' O N O N ON m ' CO CN O N d CN r f O N O N O N r f v r i oo' r f CO CO CO r f r f r r CO in r f r f r f r f CO CO VO vo r f 00 m i - H ON VO 0 0 r - CO CN CN <n r - H ON CO CO 00 O o r- r f 0 0 VO in CN Ov VO in ON 00 CN CO VO r f 0 0 I -H VO CN r - 1-H CN 00 CN ON i—H t> O N O N 00 r - H r - H o ON ON CN ON r - H 00 CN i - H i - H r - H i - H i - H CN CN CN 1-H r - H CN r ^ CN i - H O N r f r -H ON 1-H r - H VO r - H r - H r - CO ON r ^ r -H 00 O N CO CN in 00 CN 0 0 CO 0 0 VO VO o t> CO CN r> CO 0 0 r f r f m r- O N o ON ON O in r - H CN r - H co o r- VO O VO r - H O ON in r f r -H CN CN r- ON vo VO 0 0 00 00 0 0 O N ON r- ' 00° ON ON 0 0 ON ON oo' t -CN CN CN CN CN CN CN CN CN CN CN CN CN CN CN CN CO 0 0 r - H in r f CO VO VO (TN r f CO CO r f m l > r - H VO in ON 00 r f in r > U N 0 0 in ON VO VO m r f CN 00 CO vo r f VO CO in 5 0 0 0 0 r f O N r - H r -H in VO r - H 0 0 CN r -H o r f (*) CN CN r f O N in v d v d v d v d K r-' v d VO r-r N v©' r-' r-' in vd m CN CN CN CN CN CN CN CN 1 N I N CN CN CN CN CN CN r - H CN r - H ii IS ii 169 Par t ic le Size Distr ibut ion for P a n d a I i i i i i i i i I i i i i i i i i I i j I—.J I—I—l.l I 1> 10 100 1000 Par t i c le S ize (m ic ron ) 170 171 172 P a r t i c l e S i z e D i s t r i bu t i on f o r K o a l a i i i i i i i i i i i i i i i i 1 1 1 i i i_—i— i— i 1 1 1 1 10 1 0 0 1 0 0 0 Par t i c le S ize (m ic ron ) 173 1 0 1 0 0 1 0 0 0 Par t i c le S ize (m ic ron ) 174 o CO M oo ON m CO t -V O CQ! PH Hi & 00 C/5 cj C/5 C/5 cd C J X vo i ON O N vo • T t ON V O W 00 > rt o CQ to VO m ^ <! ° ed <? 73 *< oo. .1 ° PH i d PH C J to o m T t VO CD ON V O o MH Hi & 60 C/5 O a „ C/5 ^ C/5 S X X o X VO w ON © V O T f T f VO VO i W V O VO V O i W i-H oo' o > > ^ © ""3 O cd 0J ft (-* - H ^ 0 0 « d ed C J <2 00 r t < < c n 2 °^  .|p °' cw % © o i—i OH O PH 8* o .1 o eo VO C N C/5 6X5 1 . cd O u ON CO | H C/5 ^ C/5 a ? cd q <D C N H . ed i W O N X o X w vd ON C N > r - H O IT. £ > N o cd 5 •? §. cd (vj u cd C J <? oo rt <; Tf 2 0 0 tt> % O r H PH o PH 0 •H M ON 00 C N CO 2 ON ON vo O ed S C/5 C J cj C J ft s* <3 C/5 60 CD T f H-> O F—i 1 -o X > C J V O W VO 00 oo o o ON C N vo i W T f 00 ON V O W ON C N ON 00 rt ""cd o cd (0 ^ <r cj oo U cd cj ^H "~> -a < <•*•-. .§ -C/5 ^ <=> O >-H PH O PH & C J (H CD .1 m oo cj C N C J h- 1 60 CN o U ft C/5 ^ C/5 ca ^ T f T f a x cd d> SH cd X o X Tf 00 C N vq m' oo C N T f w VO > "ed O ed CO J < ^ CJ ed C J a -• rH % « o .PH O PH 175 o CD rf CN <D r-o ea d « ra-ta 00 CD H CN e8 CD CO X O X >n 00 CO CO r~ CN CO 00 rf 1 w co r - H 00 > r - H O l> £ > o *« U ea CD ca O ea CD -3 < .1 O PH CN O r-co CN O PH o rH CD .1 00 VO CD © 00 o ca T 3 60 00 •w « co P co gl O CD CD H tZ5 a x ea CD X > ca O ca CD ca O ca CD 13 < .1 o PH o PH rf 1 00 r-' «n CO CN r - H VO X H r f r-00 VO o r - H CN CN 8* o r H CD 00 t-CD 2 VO 00 ON O o P H VI CN ,1 I B S vi ^ 05 •*-> o H 1 X rf W O VO rf VO 00' P-l CN CN v d 00 £ > © O ca CD 00 o m ' vo r j < ca O ca CD <; >n — <t! r-ea ^ r-9) ^ bo ' r - H I ^ PH O S3 CN CO o CO Ov o s •s « vo C/3 CS CD r H CS 00 CO co X o X rf 1 PtH ON vo ON CN co CN 1 W 00 o co PH 1 ON CN ON o > r - H O 00 £ > © O CS CD 3 ca O . ea CD ON r - H 00 00 CN r-H << rf 2 ^ M> ™ O r - H PH S ~ " ' r - H I ^ PH 8* o rH CD .1 CN CN r f m CD vo VO 00 O ca 3 o CD PH C/3 60 CN « ft" CD r--1 ea CD r H ca X o X PLI rf 00 VO r-CN rf «n rf 1 PLI <n o CN PL) rf > ^ U r -H r - H 'ea u ea «> ~ H ON <T O r-H ^ < l a <N U ea CD <j vo IS < 00 .1 o PH O PH CN =4 o ON 00 v o CD CO VO CO CD r-H, CO CD 60 o CD H CO 1/^ 1 I a x ea CD X o X > r—i o m l £ > d | *« u ea CD ea o ca CD 13 < I o PH O PH f>6 176 Density measurements Sample Weight of sample (gm) Counter CC Density gm/cc HPGR Panda 44.76 13.65 3.28 HPGR Fox 56.52 17.37 3.25 HPGR Miser 28.07 8.95 3.14 HPGR Koala 32.99 10.86 3.04 HPGR Leslie 41.24 13.48 3.06 Panda 1 25.51 9.97 2.56 Panda 2 27.08 10.43 2.60 Panda 3 22.43 9.11 2.46 Panda 4 32.31 11.87 2.72 Fox 1 27.66 10.60 2.61 Fox 2 27.37 10.18 2.69 Fox 3 29.50 11.44 2.58 Misery 1 25.92 10.10 2.57 Misery 2 26.96 10.24 2.63 Koala 1 16.32 5.98 2.73 Koala 2 31.99 12.47 2.57 Leslie 1 39.70 13.21 3.01 Volume measurements taken with a Beckman Model 930 Air Comparison Pycnometer 177 o C 83 s © .a *M Tt o a Si s i-H O o O 0 o o o o v o r n c o . a - n o o oo r - o\ t—i TT r -rt r - H i—i r - H P H n (S CN CN N n N N rtO-H-H'-H _ rt , - H , - H rt rH rH ^ ^ c n i n ON c n ON oo i—i t~» c n v o w o < • i ON ON ON ON rt c n t N vo t N O N CN ON rt c n c n 00 ON ON O N O N ON O N 00 ON ON ON zeta CN I V O • I • T-H 00 1 i n * c n • * 00 i T t CN i o. IT) r- H O N T-H r- r- * 00 * r- ON V O r- vd vd N O V D 1 N O 1 T-H o T-H c n t N • 00 1 o f N 00 o O V O • op o N w a </") CN rt i n t N T t t N i n T t CN T t c n c n CN T t i n m ' m ' m ' i n i n i n i n i n i n i n m ' i n V O • T t T-H 1 ON I c n i • o • c n • o i T t • c n • t N • f N • V O O N 1 o N c n tN. V O c n c n 00 t N ON T - H H H ON vo c n c n T t c n c n CN t N c n CN c n c n CN f N t N CN CN i n rt i n T t r - vo c n * T t T t ON T t m r -zeta c n i c n i O N t N i n t N c n t N i CN <N 1 00 t N i cn t N i t N i t N i i n f N • T t CN N O 1 00 1 tn a T - H * r - c n i n t N rt CN O N 00 * f N CN 00 CN zeta c n c n • CN t N • c n CN i c n • i n CN • CN t N c n CN T t CN c n • CN • c n • m' CN • CN i CN CN • X H O N r H O N CN H 00 ON t - * t N ON T -H O N T - H ON ON 00 ON O N 00 00 ON O N ON zeta ON I • c n t N • CN 1 t N t N o O N c n * T t t N V O , t N i r-f N • >n CN • i n CN • T t i X a 00 O N O N CN 00 c n m i n * r - i n H H c n r - r-vd vd vd N O vd vd vd r-' zeta ON I c n t N i 00 i T f I T t 1 t N i 00 i n t N i rt t N i c n f N • V O f N • T t c n • O N 1 i n K Q. c n m t N CN CN c n r-H c n H H T t CN f N CN i n m i n i n i n m m m m m m i n i n i n m r -1 t N t N • V O CN 00 t N 00 CN 00 CN N O f N • t N f N 1 t N f N 1 o i n • i n T t • • N E O H rt t N rt rt 00 m rt c n rt f N m . - H T - H c n c n c n c n t N t N c n c n c n f N c n CN f N CN 2 5 « § ^ J pi pi pi pi pi o o o o o u g PH HH H CN cn cd cd C3 * ^ * 0 * ^ PH PH PH rt cn O O PH PH T-H tN T-H CN iS rt "c« 13 O O H4 Ui HH in a c > S 8 g .2 • - H <S2s in CO S S °- -s I a l l H •§ CH N O~-178 H co * * in o co — CN oo * * * c o CN CN co rf CN CO ON CN CN CN m in ON in rf ON o r-O ON CN in CN CN rf in in oo H H CN CN CN 6 a a. in * * in in CN' ^ ^ . in in in r-' in o in m CN H ON CO * C N r-H CN CO CO * N£> * CO CN CN * co ON 00 00 O NO m r-H r-H CN rf r-00 ON NO oo CN 1 f- ON ON ON HH CO CN CN in t~-00 00 r - H rf a r-H m * m m r- CN CN CN C CN CN ON NO m m m C 00 CN CO CO rf r-n • cN CN * co co ON 00 r- NO ON ON CN m ON 00 r o r o oo ON o r o 0 1 o IT, © oo NO CO "3 S-PH CS N a oo o ON m * c o r o CN r-n m m m m m CN H H o HH r-H 00 I I m m m HH ON CN r-H I I m m c o NO r-H r-H CN CN O r o cs N a C rf NO C ON m r-n cN m CN 00 rf rf NO * r-n r o CN 1 m m m m m d CN -—I o d * rf oo ON 00 O r-H ON CN 00 ON ON rf r-H rf CN 00 HH ON ON rf NO CN CN CN CN CN r-ON ON CN r^ m CN 00 CO o CN CN H r-H rf O m CN NO CN co m r o m rf NO NO rf H HH I CN I I * 00 CN 00 00 O CN r-H i i i O r-H CN t"-r-H CN rf H H i i r o rf 00 r-r - H m r o CN • i 00 CO 00 ON r-~ oo • i ON rf CO CN I a m r-n in in m CN d CN CN d d in in in d d d CN m d m m /—N r--CN r^ l > r-H in * HH NO O rf O ON O rf CN d d CN r-H CN ^; o r-* o m ON m CN r-H r-H CN O CN I I I r o r— rO r-H i i O ON CN r-H r-- o i oo o o o o o o o o o o o o o o cu 5C cs « a) T3 CU HH 'rH fi X 2 « « 8 O irS Q ID PH PH 2 Ui r J fg P4 (4 (g (g o o o o o & & & & & B W W H H H M m cs cS cS -o c3 cc] c3 PH PH PH X X o o PH PH HH CN ID (D in in HH CN | *CS *CS • Q q a \ Ui Ui H H 179 Z e t a p o t e n t i a l s u m m a r y f o r HPGR P a n d a 4 0 3 0 2 0 h 1 0 0 1 0 2 0 3 0 4 0 5 0 2 0 l 1 1 I 0 . 0 0 5 M N a C I 0 4 0 .001 M M g ( C I 0 4 ) 2 3 7 P H 8 1 2 p p m o f P e r c o l 3 6 8 1 0 11 1 2 I * / / *• i — * • / - V i % L igh t T r a n s m i s s i o n i 1 0 0 180 Z e t a p o t e n t i a l s u m m a r y f o r P a n d a > o c CD O Q_ CL) M 4 0 3 0 2 0 1 0 0 •10 •20 •30 •40 n 1 1 r n r > E c 0 ) -i-> o Q_ D CD M 0 . 0 0 5 N N a C I 0 4 0 .001 M M g ( C I 0 4 ) 2 I I I i i i i I • P a n d a 1 * P a n d s 2 • P a n d a 3 10 11 12 1 0 0 9 0 8 0 c 7 0 o cn CO 6 0 E OT C 5 0 o f— 4 0 -I-' sz 3 0 2 0 1 0 0 2 3 4 p p m of P e r c o l 3 6 8 181 Zeta potent ia l s u m m a r y for HPGR Fox 2 3 4 5 ppm of Percol 368 182 Z e t a p o t e n t i a l s u m m a r y f o r Fox Zeta potent ia l s u m m a r y for HPGR Misery 4 0 3 0 2 0 1 0 o 0 c CD - ) - ' - 1 0 o Q_ - 2 0 D CD M - 3 0 - 4 0 - 5 0 > E c CD o Q_ D -\-> CD M "i i i i i i r 0 . 0 0 5 M N a C I 0 4 0 .001 M M g ( C I 0 4 ) 2 0 .5 1.0 1.5 2 . 0 p p m of P e r c o l 3 6 8 0 11 1 184 Zeta potent ia l s u m m a r y for Misery Zeta potent ia l s u m m a r y for HPGR Koa la 4 0 3 0 2 0 1 0 6 - 1 0 - 2 0 - 3 0 - 4 0 - 5 0 0 . 0 0 5 M N a C I 0 4 0 .001 M M g ( C I 0 4 ) 2 3 ' 4 7 8 10 11 12 1 ' 2 3 p p m of P e r c o l 3 6 8 c o 'cn co E cn 186 Zeta potent ia l s u m m a r y for HPGR Lesl ie > c CD H — ' o Q_ D CD M 40 30 20 P 10 0 •10 •20 --30 -•40 •50 P n r "i i r > o -t—' c <D O D_ O _ <D M 0 . 0 0 5 M N a C I 0 4 0 .001 M M g ( C I 0 4 ) 2 2 3 7 8 1 a 11 12 1 2 3 ppm of Percol 368 187 Z e t a p o t e n t i a l s u m m a r y f o r L e s l i e 40 30 20 1 0 0 - 1 0 - 2 0 - 3 0 - 4 0 - 5 0 0 . 0 0 5 N N a C I 0 4 0 .001 M M g ( C I 0 4 ) 2 Leslie 1 10 11 12 2 3 4 ppm of Percol 368 188 Z e t a p o t e n t i a l s u m m a r y of K o a l a K o a l a 1 K o a l a 2 1 00 90 80 c 70 o cn CO 60 £ CO c 50 D i_ i 40 i -t-i JZ cn 30 '_l 20 10 0 2 3 4 ppm of Percol 368 189 APPENDIX D Flocculation test results for: • HPGR Panda, Panda 1, Panda 3 9 • HPGR Fox, Fox 1 • HPGR Misery, Misery 1 • HPGR Koala, Koala 1 • HPGR Leslie , Leslie 1 190 Panda 1 Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 1 16.7 67 44.3 0.0 73.9 47.3 0.0 2 33.3 133 46.0 46.6 87.8^ 43.3 38.3 3 50.0 200 50.0 39.8 87.1 67.4 49.1 4 66.7 267 44.8 63.5 70.0 55.7 89.5 5 83.3 333 52.8 73.8 63.2 57.7 60.3 Solids % w/v 25 Solution vol.(ml) 15 Density of dry sohds 2.55 Flocculant solution 0.025 % 250 ppm Dry sohds weight 5 gm 191 F l o c c u l a t i o n tes t fo r P a n d a 1 1 oo 80 60 40 20 0 \ -^ , - ' \ • E 1 0 » 1,56 • 1 5 5 - 727 • 9 1 9 j I i 0 50 100 150 200 250 300 350 gm/tonne of Flocculant 192 HPGR Panda Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0.05 0.8 3 24.9 * * * * 0.08 1.3 5 72.0 * * * * 0.10 1.7 7 75.4 * 83.1 * * 0.15 2.5 10 * * 84.4 * * 0.20 3.3 13 81.2 * 85.4 * * 0.30 5.0 20 97.3 * * * * 0.40 6.7 27 * * 90.7 * * 0.60 10.0 40 * * 92.6 * * 1 16.7 67 97.1 92.3 94.1 88.9 93.7 2 33.3 133 90.7 83.9 94.6 84.8 91.3 3 50.0 200 85.1 80.6 82.8 72.5 88.0 4 66.7 267 82.1 78.2 77.7 65.5 83.7 5 83.3 333 86.4 72.7 70.7 67.8 82.6 Solids %w/v 25 Solution vol. (ml) 15 Density of dry solids 3.28 Flocculant solution 0.025 % 250 ppm Dry sohds weight 5 gm 193 F l o c c u l a t i o n t e s t f o r H P G R P a n d a 194 Panda 3 Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0.0 0.0 0 * * * * * 0.6 10.0 67 * * 78.4 * * 0.7 11.7 78 * * 85.2 * * 0.8 13.3 89 * * 82.6 * * 0.9 15.0 100 * * 77.9 * * 1 16.7 111 92.1 90.1 91.8 77.8 48.7 2 33.3 222 93 89.1 92.2 84.4 56.6 3 50.0 333 89.9 89.5 88.6 90.6 63.8 4 66.7 444 75.7 84.2 91.3 83.6 59.4 5 83.3 556 74.3 76.4 88.8 78.9 66.4 Solids % w/v Solution vol.(ml) Density of dry solids Flocculant solution Dry solids weight 15 15 2.46 0.025 % 250 ppm 2.64 gm 195 F l o c c u l a t i o n tes t fo r P a n d a 3 196 P A N D A 1 Plate D-l:Flocculation test for Panda 1 using Percol 156. Dosage of flocculant in test tubes 1 through 5 are: 67, 133, 200, 267 and 333 gm/tonne respectfully. 197 HPGR Fox Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0 0.0 0 0.1 * * * * 0.4 6.7 27 35.5 * * * * 0.5 8.3 33 55.5 * * * * 0.6 10.0 40 90.6 * * * * 0.7 11.7 47 92.2 * * * * 0.8 13.3 53 89.8 * * * * 1 16.7 67 84.7 18.9 7.9 5.2 5.5 2 33.3 133 83.9 9.3 1.9 4.9 6.2 3 50.0 200 79.4 1.8 0.5 0.8 1.7 4 66.7 267 65.2 0.7 1.7 2 0.6 5 83.3 333 56.3 0.2 0.1 0.1 0.2 Solids % w/v 25 Solution vol.(ml) 15 Density of dry solids 3.25 Flocculant solution 0.025 % 250 ppm Dry solids weight 5 gm 198 F l o c c u l a t i o n tes t fo r HPGR Fox 1 00 I 1 1 1 1 1 1 1 1 1 1 r 0 50 100 150 200 250 300 350 g m / t o n n e o f F l o c c u l a n t 199 Foxl Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0 0.0 0 0 * * * * 1 16.7 111 0 * * * * 2 33.3 222 0 * * * * 3 50.0 333 0 * * * * 4 66.7 444 0 * * * * 5 83.3 556 0 * * * * 6 100.0 667 7.5 * * * * 7 116.7 778 15.2 * * * * 8 133.3 889 51.7 * * * * 9 150.0 1000 82.9 * * * * 10 166.7 1111 92.6 * * * * Solids % w/v 15 Solution vol. (ml) 15 Density of dry sohds 2.61 Flocculant solution 0.025 % 250 ppm Dry sohds weight 5 gm 200 Fox 1 (continued) E 10 Flocculant added with Coagulant 368 ml gm/tonne gm/tonne % Light E10 368 1.0 138 138 5.7 2.0 277 138 66 3.0 416 138 88.2 4.0 555 138 92.3 5.0 694 138 93.4 E 10 Flocculant added with Coagulant 368 ml gm/tonne gm/tonne % Light E10 368 1.0 138 277 1.2 2.0 277 277 * 3.0 416 277 78.3 4.0 555 277 93.7 5.0 694 277 75.8 Solids % w/v 6 Solution vol.(ml) 30 Flocculant solution 0.025 % Coagulant solution 0.05 % Dry solids weight 2 gm 201 F l o c c u l a t i o n tes t fo r Fox 1 o i i_ _ i _ i . i . ^ i i i i i i I 0 200 400 600 800 1000 1200 g m / t o n n e o f F l o c c u l a n t • E 1 0 ' E 1 0 with 138 g m / t o n n e 3 6 8 • E 1 0 with 2 7 7 g m / t o n n e 3 6 8 202 Plate D-3: Flocculation test for Fox I. Percol E10 is used at various concentrations ranging from 111-1111 gm/tonne (see table). Plate D-4: Fox 1 flocculation test showing the effects of Percol E10 with coagulant 368. On the left, Percol E10 dosage ranges from 138 to 694 gm/tonne using 368 gm/tonne coagulant (see table). On the right, same flocculant concentrations are used but coagulant dosage is changed to 277 gm/tonne. 203 HPGR Misery Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0 0.0 0 * * * * * 0.2 3.3 13 * * 66.4 * * 0.4 6.7 27 67.7 * 79.9 * * 0.6 10.0 40 75.5 * 85.4 * * 0.7 11.7 47 * * 84.1 * * 0.8 13.3 53 94.4 * 84.8 * * 0.9 15.0 60 93.1 * * * * 1 16.7 67 79.5 59.7 79.6 66.5 69.5 2 33.3 133 90.4 59.6 70.7 64.1 68.9 3 50.0 200 88.8 61 58 69.2 65.7 4 66.7 267 85.7 69.5 46 67.7 71 5 83.3 333 75.4 42.1 30.1 68.7 63.2 Solids % w/v 25 Solution vol. (ml) 15 Density of dry sohds 3.14 Flocculant solution 0.025 % 250 ppm Dry sohds weight 5 gm 204 F l o c c u l a t i o n tes t fo r HPGR Misery / 205 Misery 1 Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0 0.0 0 0.1 * * * * 1 16.7 111 0.1 11.6 27.5 1.3 17.5 2 33.3 222 1.1 44.5 29.2 10.9 17.4 3 50.0 333 17.7 43.3 23.0 16.3 13.4 3.8 63.3 422 30.0 * * * * 4 66.7 444 67.9 30.3 52.7 26.9 1.5 4.2 70.0 467 70.6 * * * * 4.4 73.3 489 84.9 * * * * 4.6 76.7 511 92.7 * * * * 5 83.3 556 96.7 40.2 9.5 22.8 5.6 Solids % w/v 15 Solution vol. (ml) 15 Density of dry sohds 2.57 Flocculant solution 0.025 % 250 ppm Dry sohds weight 2.64 gm 206 207 H P G R M I S E R Y ^ Plate D-5: Flocculation test for HPGR Misery. In test tubes 1 through 5 are Percol E10, Percol 155, Percol 156, Percol 727, and Percol 919 respectfully, each at 67 gm/tonne. Plate D-6: :Hocculation test for Misery 1 using Percol E10. Dosage of flocculant in test tubes 1 through 5 are: 444, 467,489, 511 and 556 gm/tonne respectfully. 208 HPGR Koala Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0 0.0 0 8.0 * * * * 0.8 13.3 53 47.9 * * * * 1 16.7 67 49.7 91.9 93.6 64.7 79.9 1.2 20.0 80 54.0 * * * * 1.4 23.3 93 87.3 * * * * 1.6 26.7 107 89.1 * * * * 2 33.3 133 88.7 54.8 91.6 91.5 61.4 3 50.0 200 90.2 36.3 86.0 93.6 75.4 4 66.7 267 89.0 62.1 78.6 74.0 42.3 5 83.3 333 82.2 11.6 77.2 72.2 63.6 Solids % w/v 25 Solution vol. (ml) 15 Density of dry sohds 3.04 Flocculant solution 0.025 % 250 ppm Dry sohds weight 5 gm 209 F l o c c u l a t i o n t e s t f o r H P G R K o a l a 1 oo 80 h 60 40 20 0 E1 0 1 56 1 5 5 727 9 1 9 l _ \ / 1 0 50 100 150 200 250 300 350 g m / t o n n e o f F l o c c u l a n t 210 Koala 1 Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0 0.0 0 18.9 * * * * 0.5 8.3 56 74.8 * * * * 0.7 11.7 78 60.5 * * * * 0.9 15.0 100 76.9 * * * * 1 16.7 111 71.9 91.7 87.7 80.3 80.0 1.1 18.3 122 73.2 * * * * 1.5 25.0 167 91.3 * * * * 2 33.3 222 94.6 92.7 78.7 82.6 78.5 2.5 41.7 278 89.2 * * * * 3 50.0 333 90.6 77.6 70.8 88.7 87.3 4 66.7 444 86.2 68.6 69.2 78.6 93.3 5 83.3 556 83.7 67.6 63.0 78.1 95.0 Solids % w/v 15 Solution vol. (ml) 15 Density of dry sohds 2.72 Flocculant solution 0.025 % 250 ppm Dry sohds weight 2.64 gm 211 KOALA 11 i Plate D-7: Flocculation test for Koala 1. In test tubes 1 through 5 are Percol E10, Percol 155, Percol 156, Percol 727, and Percol 919 respectfully, each at 67 gm/tonne. Plate D-8: :Flocculation test for Koala 1 using Percol E10. Dosage of flocculant in test tubes 1 through 5 are: 111, 222, 333, 444 and 556 gm/tonne respectfully. 212 f 213 HPGR Leslie Flocculant added % Light Transmission Flocculant ml ppm(w/v) anne E10 155 156 727 919 0 0.0 0 54.9 * * * * 0.2 3.3 13 65.1 * 85.8 * * 0.3 5.0 20 62.3 * 93.6 * * 0.4 6.7 27 79.2 * 94.6 * * 0.6 10.0 40 83.3 * 96.4 * * 0.8 13.3 5 93.5 * 98.0 * * 1 16.7 67 94.5 90.9 95.5 85.7 88.9 2 33.3 133 85.0 75.2 90.3 70.6 79.9 3 50.0 200 78.7 69.3 90.4 67.5 81.9 4 66.7 267 76.4 66.9 69.8 73.6 76.5 5 83.3 333 73.6 67.3 71.7 61.5 75.9 Solids % w/v 25 Solution vol.(ml) 15 Density of dry sohds 3.06 Flocculant solution 0.025 % 250 ppm Dry sohds weight 5 gm 214 215 Leslie 1 Flocculant added % Light Transmission Flocculant ml ppm(w/v) g/tonne E10 155 156 727 919 0 0.0 0 * * * 49.5 * 0.20 3.3 22 * * * 56.9 * 0.30 5.0 33 * * * 60.3 * 0.35 5.8 39 * * * 69.1 * 0.40 6.7 44 * * * 88.0 * 0.45 7.5 50 * * * 83.3 * 1 16.7 111 84.4 88.6 87.3 96.1 92.4 2 33.3 222 78.0 75.9 81.2 91.3 94.6 3 50.0 ' 333 77.9 78.2 76.9 83.2 97.1 4 66.7 444 72.6 80.3 60.7 83.2 95.3 5 83.3 556 72.0 76.1 62.9 80.6 91.1 Sohds % w/v 15 Solution vol. (ml) 15 Density of dry sohds 3.01 Flocculant solution 0.025 % 250 ppm Dry sohds weight 2.64 gm 216 F l o c c u l a t i o n t e s t f o r L e s l i e 1 1 oo. 0 100 200 300 400 500 gm/tonne of Flocculant 217 

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