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Improvements in comminution efficiency through high velocity impact Moosavi zadeh, Amir Bahador 2012

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i   IMPROVEMENTS IN COMMINUTION EFFICIENCY THROUGH HIGH VELOCITY IMPACT  by Amir Bahador Moosavi zadeh B.A.Sc., University of British Columbia, 2009   A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE in THE FACULTY OF GRADUATE STUDIES (Mining Engineering)  THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) April 2012  ©Amir Bahador Moosavi zadeh, 2012   ii  ABSTRACT In order to conduct efficient physical separation of a valuable mineral from an ore, the mineral in question must be liberated (broken into finer particles). Comminution, the physical process of rock breakage, accounts for a large portion (50 to 70%) of energy costs in the mining industry. Conventional comminution uses compressive forces to initiate and propagate cracks throughout the rock mass, yet it actually breaks under tension. Converting compressive forces into tensile ones is only 1 to 2 percent efficient. Blasting rock, in contrast, shows energy efficiencies of the order of 10 to 20%. This difference exists because a larger amount of forces are applied directly in tension and because the velocity of impact (and the rate of energy input ) is orders of magnitude higher (10,000 m/s versus 10 m/s). This thesis reports on studies that build on previous work that showed high strain rates achieved through high speed impact can enhance the energy efficiency of comminution. The work examines the effects of high energy input and impact speed as separate, but interconnected, phenomena to explain from where the efficiency improvement derives. The project also takes a preliminary look at rock-on-rock breakage. Magnetite samples of varying sample weights and size distributions were impacted by a projectile at various speeds. Different materials and weights of projectile were studied. Before and after each experiment, the specific surface area of the sample was measured and the energy recovered as new surface energy was calculated. The results indicate that energy efficiency increases to about 5% (over 3 times that observed in conventional comminution) as impact speed reaches the range of 200 to 300 ms-1. Above this velocity, the efficiency begins to fall off although significant comminution at higher than normal efficiency is still attained. The efficiency improvement results from both increased input energy and impact speed. Suggestions are given as to how this energy improvement could be scaled-up into a Barmac crusher. Recommendations are given for a new target chamber in the UBC CERM3 high-velocity facility in which the peak efficiency point at maximum compression might be eliminated in future testwork.   iii  TABLE OF CONTENTS ABSTRACT .......................................................................................................................................... ii TABLE OF CONTENTS...................................................................................................................... iii LIST OF TABLES ................................................................................................................................. vi LIST OF FIGURES ............................................................................................................................. vii ACKNOWLEDGMENTS ..................................................................................................................... xi 1 INTRODUCTION .......................................................................................................................... 1 1.1 Comminution Energy .............................................................................................................. 1 1.2 Problem Statement .................................................................................................................. 2 1.3 Hypothesis of the Thesis ......................................................................................................... 4 1.3.1 UBC-CERM3 High Velocity Impact Facility ................................................................. 5 1.4 Objectives of the Thesis .......................................................................................................... 6 2 COMMINUTION PROCESSES .................................................................................................... 8 2.1 Summary ................................................................................................................................. 8 2.2 Current Comminution Technology ......................................................................................... 8 2.2.1 Blasting Operations ......................................................................................................... 8 2.2.2 Crushing Operation ....................................................................................................... 10 2.2.2.1 Jaw Crushers ............................................................................................................. 10 2.2.2.2 Gyratory Crusher ...................................................................................................... 11 2.2.2.3 Cone Crushers ........................................................................................................... 12 2.2.3 Grinding Mills............................................................................................................... 13 2.2.4 Hammer Mills ............................................................................................................... 16 2.2.5 Attrition Mills ............................................................................................................... 16 2.2.6 Rolling Compression Mills ........................................................................................... 17 2.2.6.1 High Pressure Grinding Rolls (HPGR) ..................................................................... 18 2.2.7 Barmac Crusher ............................................................................................................ 19 2.2.8 Jet Milling ..................................................................................................................... 21 3 TESTWORK AND PROCEDURE .............................................................................................. 23 3.1 Summary ............................................................................................................................... 23 3.2 Sample Preparation ............................................................................................................... 23 3.3 Experiments .......................................................................................................................... 26 3.3.1 Samples ......................................................................................................................... 26 3.3.2 Procedure ...................................................................................................................... 27 iv  3.3.2.1 BET Surface Area Analyzer ..................................................................................... 29 3.3.2.2 Impact Testing using the High-Velocity Impact Facility .......................................... 29 4 RESULTS AND DATA ANALYSIS ........................................................................................... 31 4.1 Summary ............................................................................................................................... 31 4.2 The Base Case (1/2"St-MagAD Series) ................................................................................ 31 4.3 Reproducibility and Error Minimization .............................................................................. 34 4.4 The Effect of Particle Size Distribution ................................................................................ 40 4.5 The Effect of Sample Mass ................................................................................................... 44 4.6 The Effect of Bullet Size and Material ................................................................................. 48 4.7 Specific Surface Area ........................................................................................................... 54 5 DISCUSSION ............................................................................................................................... 56 5.1 Summary ............................................................................................................................... 56 5.2 Impact Speed and Input Energy Models ............................................................................... 56 5.2.1 Impact Speed vs. Input Energy ..................................................................................... 56 5.2.2 Energy of the New Surface Area .................................................................................. 59 5.2.3 Error Minimization ....................................................................................................... 61 5.2.4 Reproducibility ............................................................................................................. 61 5.3 Bond Efficiency .................................................................................................................... 62 5.4 The Peak ............................................................................................................................... 63 5.4.1 Effect of Particle Size Distribution ............................................................................... 64 5.4.2 Effect of Sample Mass .................................................................................................. 64 5.5 Rock-on-Rock Breakage ....................................................................................................... 65 5.6 A Modified Barmac Crusher ................................................................................................. 66 6 CONCLUSIONS AND RECOMMENDATIONS ....................................................................... 70 6.1 Conclusions ........................................................................................................................... 70 6.2 Future Work .......................................................................................................................... 71 6.2.1 Enhancement of the Quality of Research ...................................................................... 71 6.2.2 Commercialization ........................................................................................................ 72 REFERENCES ..................................................................................................................................... 73 APPENDIX A: EFFICIENCY CALCULATIONS .............................................................................. 78 APPENDIX B: SIEVE ANALYSIS RESULTS................................................................................... 83 APPENDIX C: BOND WORK INDEX DETERMINATION (MAGNETITE) ................................ 115 APPENDIX D: CALCULATIONS OF THE MODIFIED BARMAC CRUSHER ........................... 120 v  APPENDIX E: RECOMMENDED MODIFICATION OF TARGET CHAMBER .......................... 121 APPENDIX F: SAMPLE ASSAYING RESULTS ............................................................................ 123   vi  LIST OF TABLES Table 1. Estimated energy efficiency of comminution and Bond Work Index for several minerals. ..... 3 Table 2. Summary of all experiments ................................................................................................... 26 Table 3. Physical characteristics of magnetite ...................................................................................... 27 Table 4. P80, Bond energy and weight percent -37 µm material and -150 µm material of the Base Case....................................................................................................................................................... 32 Table 5. Material loss during experiments for the 1/2"St-MagAD Series ............................................ 33 Table 6. P80 and weight percent -150 µm material for MagA to MagD Series ................................... 36 Table 7. P80, Bond energy, and weight percent of - 37 µm material for MagE, MegF and MagG Series..................................................................................................................................................... 42 Table 8. Estimated peak efficiency and velocity for each feed size ..................................................... 44 Table 9. P80, Bond energy and weight percent of -37 µm and -150 µm material ................................ 46 Table 10. P80, Bond energy, and wt% -150 µm material for 6.35mm steel, 25.4mm steel, and 12.7mm Al and glass bullets. .............................................................................................................................. 50   vii  LIST OF FIGURES Figure 1. Distribution of electricity costs in a typical cement plant (Scheuer & Ellerbrock, 1992) ....... 2 Figure 2. A particle with inherent flaws being impacted ........................................................................ 4 Figure 3. Design configuration of the UBC-CERM3 high-velocity impact apparatus (Sadrai et al., 2011) ....................................................................................................................................................... 5 Figure 4. Energy efficiency as a function of impact velocity for Q=Quartz, L=Limestone, and S = Salt Rock (A = 13 gram sample and B = 25 gram sample) (Sadrai et al., 2011) ........................................... 6 Figure 5. Jaw crusher mechanism (Lindqvist & Evertsson, 2003). ...................................................... 11 Figure 6. Cross-sectional view of a gyratory crusher (Biddulph, 1976). .............................................. 12 Figure 7. Schematics of a cone crusher ................................................................................................ 13 Figure 8. Ball mill schematics .............................................................................................................. 14 Figure 9. Rod mill operation ................................................................................................................. 15 Figure 10. A laboratory size hammer mill. ........................................................................................... 16 Figure 11. Ring attrition mill. ............................................................................................................... 17 Figure 12. Laboratory attrition mill ...................................................................................................... 17 Figure 13. Schematics of HPGR  (Napier-Munn, 1996) ...................................................................... 19 Figure 14. Schematic of Barmac crusher operation (Jankovic et al., 2004) ......................................... 20 Figure 15. Components and operation of a jet mill. ............................................................................. 21 Figure 16. Crushing flowsheet .............................................................................................................. 23 Figure 17. Sieve analysis on crushed magnetite ................................................................................... 24 Figure 18. Specific Surface Area (SSA) of magnetite as a function of particle size ............................ 25 Figure 19. Experimental flowchart ....................................................................................................... 28 Figure 20. UBC-CERM3 high velocity impact facility ........................................................................ 30 Figure 21. Particle size analysis for 10 gram 1-2 mm size magnetite samples impacted by 1/2" long steel bullet ............................................................................................................................................. 32 Figure 22. Bond energy as a function of total input energy for the 1/2"St-MagAD Series .................. 33 Figure 23. Energy efficiency as a function of impact speed for magnetite samples with a size distribution of 1 to 2 mm, impacted using 12.7 mm length steel bullets. ............................................. 34 Figure 24. Particle size analysis of 10 gram magnetite samples, impacted by a 12.7 mm length steel bullet, with feed size distributions of a) 1 to 1.2 mm b) 1.2 to 1.4 mm c) 1.4 to 1.68 mm d) 1.68 to 2 mm. ....................................................................................................................................................... 35 Figure 25. P80 as a function of impact speed for samples with various size distribution (between 1 to 2mm) ..................................................................................................................................................... 37 viii  Figure 26. Bond energy as a function of impact speed for samples with various size distribution (between 1 to 2mm) .............................................................................................................................. 38 Figure 27. Bond energy as a function of total input energy for samples with various size distribution (between 1 to 2mm) .............................................................................................................................. 38 Figure 28. Impact efficiency as a function of impact speed for magnetite samples (impacted using a 12.7 mm length steel bullets) with a size distribution of a) 1 to 1.2 mm b) 1.2 to 1.4 mm c) 1.4 to 1.68 mm d) 1.68 to 2 mm. ............................................................................................................................ 39 Figure 29. Size analysis for 10g mag. samples impacted by a 12.7 mm long steel bullet, with a feed size distribution of a) 500 to 589 µm b) 210 to 300 µm c) 90 to 150 µm. ............................................ 41 Figure 30. Bond energy as a function of total input energy for samples  of different size distributions  .............................................................................................................................................................. 43 Figure 31. Comparison of energy efficiency vs. impact speed for samples of different size distributions .......................................................................................................................................... 43 Figure 32. Particle size analysis for 5g, 1-2 mm size magnetite samples ............................................. 45 Figure 33. Particle size analysis for 15g, 1-2 mm size magnetite samples ........................................... 45 Figure 34. Bond energy as a function of total input energy for samples of various masses ................. 47 Figure 35. Comparison of energy efficiency vs. impact speed for samples of different mass ............. 47 Figure 36. Size analysis for 1 to 2 mm, 10g magnetite samples impacted by a) 6.35 mm long steel bullet; b) 25.4 mm long steel bullet; c) 12.7 mm long aluminum bullet; d) 12.7 mm long glass bullet.  .............................................................................................................................................................. 49 Figure 37. Comparison of Bond energy as a function of input energy for various bullet types ........... 51 Figure 38. Comparison of energy efficiency vs. impact speed for various bullet types ....................... 52 Figure 39. Comparison of energy efficiency vs. input energy for various bullet types ........................ 52 Figure 40. Sieve analysis performed on glass projectiles after impact ................................................. 53 Figure 41. Efficiency as a function of impact speed for magnetite samples impacted by glass, glass bullet breakage and the total breakage efficiency ................................................................................. 54 Figure 42. Specific Surface Area (SSA) as a function of impact speed for particle sizes of a) -37 µm b) -150 µm +37 µm c) +150 µm ........................................................................................................... 55 Figure 43. Comparison of energy efficiency vs. impact speed for various bullet types ....................... 57 Figure 44. Comparison of energy efficiency vs. input energy for different bullet types ...................... 58 Figure 45. Energy efficiency as a function of impact velocity for various constant energy inputs. ..... 59 Figure 46. Graph of energy of generates surface area as a function of input energy for various bullet types ...................................................................................................................................................... 60 Figure 47. Polynomial fit representing energy of new surface area as a function of input energy ....... 61 ix  Figure 48. Reproducibility of experiments on all samples with particles between 1 to 2 mm in size impacted by steel bullets ....................................................................................................................... 62 Figure 49. Bond efficiency as a function of projectile speed................................................................ 63 Figure 50. Efficiency as a function of energy per mass for samples of various masses ....................... 65 Figure 51. Comparison of the combined efficiency during impact by glass with the base case .......... 66 Figure 52. Size distribution of a crushed iron ore sample using a Barmac Crusher (tip speed: 63 ms-1 ) (Metso Minerals Limited) ..................................................................................................................... 69 Figure 53. Size analysis of the original feed ....................................................................................... 118 Figure 54. Size analysis of the final product....................................................................................... 119 Figure 55. Schematics of a modified target chamber ......................................................................... 122 xi  ACKNOWLEDGMENTS I would like to take this opportunity to thank the many wonderful people who kindly lend me their support and assistance whether through their words of wisdom or through encouragement.  I would like to extent my appreciation for the support and guidance that my supervisor, Dr. John Meech provided me with. This study could not be done without his invaluable input, as well as the resources he provided me throughout my work. John, in addition to being a great supervisor with extensive technical knowledge, you are a great human being who taught me many valuable life lessons.  I would also like to thank Dr. Desmond Tromans for his valuable input and support. I would also like to thank members of the Department of Mining Engineering - faculty, staff, and students - as well as members of the university community whom I have had the pleasure of knowing, for their assistance throughout my studies and for truly enhancing my university experience.  Most importantly, I would like to sincerely acknowledge the support and encouragement of my wonderful family, especially my mother, Ms. Elham Asefi and my father, Mr. Ghodratollah Moosavi- zadeh, for their patience and continuous assistance in every step of my life. Words cannot describe my level of appreciation for your sacrifices, thus, this work is dedicated to my wonderful family: my parents, my sister Shaghayegh, my brother AmirAbbas, and my sister-in-law Behnoush and our precious Nava.      1  1 INTRODUCTION Comminution is a crucial process in mining and mineral processing operations. The process refers to the size reduction of solid materials through application of energy, usually by means of mechanical forces. Comminution is required to liberate valuable minerals from gangue (or waste minerals) and it consumes a major amount of the total energy used during mining and mineral recovery. It is reported that more than half the energy used in a typical mineral processing plant is for size reduction and liberation of minerals (Walkiewicz et al., 1991). In a typical cement plant, comminution (crushing and grinding) consumes over 60 percent of all electrical expenditures (Fujimoto, 1994).  Comminution efficiency in this work is defined as the ratio of the useful output energy to total input energy. Fundamentally, this can be calculated from the ratio of new surface energy to the total input energy. With this definition, the efficiency of conventional comminution has been shown to be of the order of only 1 to 2% (Whittles et al., 2006; Tromans & Meech, 2002; Walkiewicz et al., 1991), with most input energy being dissipated as heat (Austin, 1984). From measurements performed on a single stage ball mill, 85% of the energy was dissipated as heat, 14% was converted to kinetic energy with the actual efficiency into the ore being only 1% (Alvarado et al., 1998).  As such, even minor improvements in efficiency (1 or 2 percent) can result in considerable energy savings, thereby justifying the conduct of research on energy efficiency in comminution.  1.1 Comminution Energy Crushing and grinding are the major stages of comminution. The main objectives of comminution are to produce particles of a required size and shape, to liberate valuable minerals from waste before concentration, and/or to increase surface area available for chemical reaction. About 50% of total comminution costs are attributed to energy consumption (Radziszewski, 2000) and it is estimated that comminution consumes over 3% of the total electricity generated worldwide (Fuerstenau et al., 1999). Grinding accounts for 90% of comminution energy compared to crushing which uses about 5-7% and 2  blasting at 3-5% (Alvarado et al., 1998). A breakdown of energy expenditures in a typical cement plant is shown in Figure 1.   Figure 1. Distribution of electricity costs in a typical cement plant (Scheuer & Ellerbrock, 1992)  Energy consumption during rock breakage depends on the availability of micro- or macro-cracks within particles. Less and less of these fractures exist as material becomes finer (below about 100 microns) meaning these sizes are more resistant to breakage. For ultra-fine grinding, the very low microcrack density significantly increases a material's work index by as much as several orders of magnitude. 1.2 Problem Statement Comminution efficiency in this work is determined from the ratio of the difference between the measured surface energy of the product and the feed (i.e., the energy of new surface created during size reduction) to the mechanical energy supplied to the machine that performs size reduction (Fuerstenau & Abouzeid, 2002). In a practical sense, the energy required to break a tonne of material from an infinite 80% passing size to an 80% passing size of 100 micron is defined as the Bond Work Index. This value can be determined from laboratory testwork as well as from observations taken Quarry crushing and prehomo Raw material grinding Feed homogenization burning and cooling Finish cement grinding Conveying, packing and loading 5% 5% 38% 24% 6% 22% 3  from an operating plant. Ratios of the plant value to the laboratory value can be used to evaluate the effectiveness of the operating plant which of course is subject to a great deal of variations in ore conditions, as well as plant operating changes. These efficiencies will typically range from a low level of about 75% to a high of perhaps 110%, but this does not reflect the real efficiency of energy used to break the ore. Theoretical estimations suggest that the true energy efficiency during crushing and grinding is of the order of 1 to 2% (Tromans & Meech, 2002). Table 1 shows the estimated comminution energy efficiency and Bond work index for several minerals calculated by a thermodynamic analysis.  Table 1. Estimated energy efficiency of comminution and Bond Work Index for several minerals.  (Tromans & Meech, 2002) Mineral Wi (kWh/ton) Efficiency (%) Galena 10.19 0.27 Fluorite 9.76 0.58 Pyrite 8.9 0.78 Garnet 12.37 0.94 Feldspar 11.67 0.97 Magnetite 10.21 1.38 Hematite 12.68 1.76 Rutile 12.12 2.03 The energy efficiency of particle fracture depends on several factors such as the loading force and the size and orientation of inherent micro-fractures in the particles. Generally, it may take a number of impacts before a force sufficient to propagate a fracture, is applied. Impacts that do not result in fracture generate elastic strain energy which is stored within the particles as thermal heat without any new surface area being produced which contributes to the inefficiency of the process (Tromans & Meech, 2004). Impact forces applied to a particle, as shown in Figure 2, result in compression parallel to the axis of impact and tensile stresses normal to the axis of impact. Interaction of these stresses may lead to the failure of the material with the orientation of internal flaws in the material playing a 4  key role in determining breakage efficiency. All rock particles fracture in tension, hence the transfer of a compressive force to a tensile stress is a major factor related to why efficiency is so low.   Figure 2. A particle with inherent flaws being impacted 1.3 Hypothesis of the Thesis During comminution, kinetic energy applied through physical contact will transform to potential energy (stored in the material as surface energy), heat, and sound. Energy stored in the material as new surface areas is the useful energy with only a small fraction of the total energy (about one to two percent) contributing to the new surfaces.  However, energy efficiency in blasting, which is the first stage of the breakage of material, is at least an order of magnitude higher than that of grinding mills and crushers. The calculated efficiency ranges from about 13 to about 20%. Despite the high costs associated with drilling and blasting, downstream cost savings in crushing and grinding make this unit operation an effective method to increase overall comminution effectiveness (Eloranta, 1997). There are three factors that contribute to the high energy efficiency of blasting: first, the sudden increase in pressure and rapid rate of energy release causing the rock to fracture (i.e., energy input); second, the shock wave produced by blasting moves in all directions throughout the rock with a velocity over 2,000 ms-1 (i.e., better conversion of compression to tension forces) (Formby & Wharton, 1996); and thirdly, the material after blasting generally has a higher density of micro-cracks which reduce the material's Work Index. Based on these ideas, this research project was commenced in 2004 to examine if the intermediate stress regime 5  that exists between crushing equipment and blasting could be exploited to produce higher energy efficiencies. The approach taken was to design a facility to impact rock at high velocities (Sadrai et al., 2011) and a successful demonstration project showed that energy efficiency could be improved significantly as the impact velocity increased.  The research project described here was initiated to increase our understanding of how energy use improves when compressive forces are applied at high rates. The methodology of using the high impact velocity facility was refined to ensure reproducibility and better correlation between new surface area created and energy input at high impact velocities.  1.3.1 UBC-CERM3 High Velocity Impact Facility The UBC-CERM3 high velocity impact facility (operating at speeds between 100 to 350 ms -1) was built to study how impact velocity can improve fragmentation and minimize energy use. Aggregated rock samples are fragmented inside a chamber by being subjected to the impact of a projectile. The apparatus uses compressed gas at high pressure (up to 250 psi) to accelerate the projectile. Immediately before impact, the projectile speed is measured by two pairs of fixed laser diode detectors, which record the time of passage of the projectile (Sadrai et al. 2006). Figure 3 is a schematic diagram of the facility.    Figure 3. Design configuration of the UBC-CERM3 high-velocity impact apparatus (Sadrai et al., 2011)  The initial testwork used limestone, quartz, and rock salt. These materials were selected to observe the effect of impact velocity over a range of Poisson's ratios and porosities. For each material, 6  samples of -2mm + 1mm were prepared and impacted at different speeds. The results showed a clear influence of velocity on energy efficiency for all materials up to about 250 ms-1 with the suggestion that a peak may exist in that region (see Figure 4).   Figure 4. Energy efficiency as a function of impact velocity for Q=Quartz, L=Limestone, and S = Salt Rock (A = 13 gram sample and B = 25 gram sample) (Sadrai et al., 2011)  While the results show that energy efficiency increases with impact velocity, considerable scatter is evident. As a result, this project was undertaken to improve reproducibly and determine the influence of velocities above the apparent peak point. In addition, it was considered important to examine if the energy input rate or the level of velocity impact was more important in increasing energy efficiency.   1.4 Objectives of the Thesis The purpose of this research is to explore methods to improve energy efficiency of comminution (processes and/or equipment) with the goal to decrease the cost of comminution. The specific objectives are as follows:  7  head2right To investigate the relationship between energy input during fragmentation and the amount of new surface area created within the rock mass. head2right To investigate the effects of particle size and bed depth of particles on the relationship between energy efficiency and impact velocity. head2right To separate the effects of impact velocity and input energy on energy efficiency. head2right To simulate and examine relationships for rock-on-rock impact. head2right To improve the reproducibility of testwork using the high velocity impact facility.   8  2 COMMINUTION PROCESSES 2.1 Summary This section provides background on current comminution technology by reviewing the unit operations of blasting, crushing and grinding. Some of the specialized comminution equipment aimed at increasing energy efficiency and the basic principles of their operation are outlined. Previous work on the relationship between impact velocity and comminution efficiency is presented. Calculations are presented to demonstrate the energy requirements for one type of impact machine were it to be operated at higher velocities. 2.2 Current Comminution Technology Comminution technology is widely used in modern industry, with all mining and mineral processing operations being major users of comminution equipment. Applications range from crushing of mined ore to grinding of very fine particles to produce advanced materials. The first stage of comminution includes rock cutting and blasting with blasting being the dominant method. Researchers have shown that an integrated approach comminution across the blasting and crushing stages can provide substantial energy and cost savings since the energy efficiency in blasting lies between 13 to 20 % (Dance et al., 2007; Workman, 2003; Paley & Kojovic, 2001; Dance, 2001; Eloranta, 1995).  2.2.1 Blasting Operations The extraction of rock mass and subsequent fragmentation generally begins with drilling and blasting techniques. A number of holes are drilled using a specified pattern and these are filled with explosive. The blast is initiated row by row with micro-second to milli-second delays to allow the rock mass to move out through the free-face. The degree of fragmentation is affected significantly by the blast hole pattern – the distance and orientation between adjacent holes as well as the accuracy of the holes drilled with respect to the desired directions and lengths. The type of explosive is an important factor 9  with ammonium nitrate and fuel oil (ANFO) being the dominant choice. Environmental factors such as water infiltration into the holes can also play a major role in the success of a blast.  Immediately following detonation, two types of loading forces are applied to the rock: a shock wave that quickly travels out from the explosion cavity (drill hole) into the material surrounding the borehole and a longer duration gas pressurization loading (Fourney et al., 1993). Controversy exists over which type of loading has the highest contribution to fragmentation. Stress waves propagate throughout the rock in all directions at high velocities to form crack patterns which then separate from the application of the high pressure explosion gas onto the crack surfaces (Donzé et al., 1997; McHugh, 1983).  Energy efficiency is influenced by many factors including burden, stemming length, delay period between rows, placement of booster charge, booster ratio, and blast pattern (Singh et al., 1994).  Blasting provides high energy efficiency in comparing surface area (energy) change of the rock mass with the chemical energy released from the explosion. A major reason behind this high level is that the transmitted energy directly produces tensile stresses causing fragmentation along the boundaries between blast holes. During blasting, impact velocity is much higher (3,000-6,000 ms-1) than that within conventional mechanical equipment leading to an increased crack density. Moreover, existing flaws and discontinuities help distribute the explosive gas throughout the rock helping to propagate these cracks. In addition to fragmentation, the strength of the surrounding rocks is diminished because of the new cracks introduced, making subsequent operations more efficient. Comminution efficiency can be improved by intensified blasting (Chi et al., 1996). Reducing the blast burden and spacing by 25% led to an equal energy reduction during crushing and a 9% improvement in grindability. Blasting is typically limited to achieving a top size (450 to 600 mm) sufficient to load and transport material to the primary crusher. These constraints are due to the cost of drilling and blasting and the problem of fly-rock generation and noise that may impact on nearby facilities.  10  2.2.2 Crushing Operation The main objective of crushing is to reduce the material in size by breaking large particles into fragments. Crushers are designed to reduce particle size to a specific top size and sometimes, it is a requirement that a minimum amount of fines is produced, although it is impossible to produce only material larger than a desired minimum size. Since the main objective is size reduction, crushers are usually compared using the term "Reduction Ratio". This ratio is a performance metric defined as the 80% passing particle size in the feed divided by that in the product. The energy used is affected by feed size and hardness changes together with idling periods (or other delays) while awaiting new ore. Crushing machines are normally massive pieces of equipment because of the tough nature of their operating environment. With all crushing equipment, crushing action results from stresses applied to particles by a moving solid surface within the equipment working against another (moving or stationary) solid surface. In the case of a gyratory or cone crusher, a cone (mantle) moves within a stationary bowl while in a jaw crusher, two plates are used – one moving and one stationary. The stresses produce strain within the ore particles leading to fracture when the deformation limit is reached. Crushers are commonly used for coarse (primary) breakage to 100 - 250 mm (4 - 10 inches), intermediate (secondary) to 25 - 65 mm (1 - 2.5 inches), and fine crushing to 12-20 mm (½ - ¾ inches). Both dry (< 5 %H2O) and wet (~10 %H2O) crushing of materials can be conducted, but coarse crushing is always done dry with intermediate crushing typically being done on dry materials as well. When the ore is very wet or contains high quantities of mud and/or clay minerals, then wet crushing may be used to advance the material through the equipment (Water Flush® crushing). 2.2.2.1 Jaw Crushers Jaw crushers are one of the most commonly used types of crushing equipment (Jinxi et al., 2007; Georget & Lambrecht, 1982). This crusher is mainly used as a primary crusher and consists of two vertical jaws. One jaw is fixed while the other moves back and forth using a cam mechanism. As 11  shown in Figure 5, material is fed from the top where the distance between the jaws is highest (known as the gape). As material falls through the machine, movement of the jaws together with the narrowing distance leads to fracture as particles and jaws impact each other. Jaw crushers are typically used to treat ores at tonnage rates below 1,000 tph. Crushing occurs on the inward stroke of the moving jaw while product is discharged on the opening stroke.   Figure 5. Jaw crusher mechanism (Lindqvist & Evertsson, 2003).  2.2.2.2 Gyratory Crusher Gyratory crushers can be thought of as jaw crushers, only with circular plates. Figure 6 shows the cross-sectional view of this type of crusher. Tonnage rates are significantly higher than that of jaw crushers with individual units capable of treating up to 10,000 tph. Crushing and discharge take place continuously as the mantle moves around inside the bowl to be closed on one side and open on the other. In most high tonnage open-pit operations, gyratory crushers are used as primary crushers, especially when processing hard and abrasive ores. Compared to other crushers, they have the largest unrestricted opening and provide more flexibility in terms of moderating feed rates (Major, 2002). Feed Product Fixed jaw Moving jaw 12   Figure 6. Cross-sectional view of a gyratory crusher (Biddulph, 1976).  With primary crushers the size of a unit is usually characterized by the gape (or opening) required to process the ore at its run-of-mine top size and its tonnage rate. These crushers are "set" by adjusting the Open-Side setting which essentially controls the top size of the discharged product.  2.2.2.3 Cone Crushers Of all machines used in crushing plants, cone crushers have seen the greatest advancements and improvements in performance (Svensson & Steer, 1990). In a cone crusher, used mainly in secondary crushing plants, rocks are compressed between an eccentrically rotating spindle and a concave bowl similar to the configuration of a gyratory crusher, except in the latter case the bowl and mantle orientation is opposite (i.e., the bowl is convex). As large pieces of rock enter the crusher, they break and slide down to a lower position until they reach a size small enough to pass through the opening at the bottom of the crusher. Figure 7 demonstrates the operation of a cone crusher. With these units, the Closed-Side Setting is used to control product size and productivity mainly because of the difficulty in measuring the setting which is usually done using a piece of lead on a string and passed through the 13  crusher while it is idling. The angle and opening size of these crushers are different depending  on the performance – either a secondary function (1 to 2.5") or a tertiary function (0.5 to 0.75").    Figure 7. Schematics of a cone crusher   2.2.3 Grinding Mills The main objective of grinding is also size reduction, but to a much finer size wherein about 80% of all valuable particles are fully liberated from gangue material. This limitation is generally determined by a cost/benefit analysis in which 80% liberation is the typical design target. Grinding equipment normally consists of a heavy surface that slides or rolls over another solid surface, with material caught between the two surfaces. This mechanism leads to shearing and impact stresses in the material, causing it to be ground by attrition or impact into very small sizes (between 10 to 200 microns). Typically, the grinding action is achieved by tumbling steel rods or balls inside a cylinder or autonomously, using larger ore pieces (or pebbles) to break smaller particles. Compared to crushers, grinding units possess a much larger reduction ratio. For crushing, the typical reduction ratio lies from 3 to 10, while for grinding it can be 100 or larger. Grinding mills are most often used for wet applications. However, there are some cases, such as coal preparation for combustion or in the 14  preparation of chemicals that may or may not be soluble, where ball mills are used to grind dry material – typically to ultra-fine sizes (less than 20 microns). Energy is input into the rotating drum through a gear trunion that rotates the drum such that the velocity of the coarsest and heaviest material (generally the largest steel rod or ball) is about 80% of the critical velocity (the speed at which the ball centrifuges inside the drum as it rotates). Changes in feed size and ore hardness affect the actual energy required for a specific tonnage rate, but generally the steel charge (35-40% of the internal volume) determines the majority of energy needed. In the case of autogenous and semi-autogenous mills where the steel charge is from 0 to 18% of the total volume, the speed of the mill may be adjusted to compensate for varying ore parameters.  Figure 8 shows the general operation of a ball mill while that of a rod mill is depicted in Figure 9.   Figure 8. Ball mill schematics 15   Figure 9. Rod mill operation  Grinding mills come in a variety of lengths and diameters. Typical rod and ball mills have length to diameter ratios greater than 1.0 and, in some cases separate compartments are used to isolate the steel balls. In the case of rod mills, although these types of mills have a self-regulating size control which generates a size distribution narrower than that of an equivalent ball mill, these units have reached a point of maximum length of about 6 m at which point the rods begin to bend under their own weight. As milling equipment has increased in size to reduce maintenance costs and downtime, rod mills have gone out of vogue to be replaced by large capacity ball mills and autogenous or semi-autogenous mills. Autogenous and SAG milling has increased dramatically over the past forty years due to the reduction in steel consumption and the desire for higher-capacity milling circuits. SAG and Ag mills can receive feed directly from a primary crusher, hence the secondary crushing plant can be eliminated. Many of these mills have length to diameter (L:D) ratios of less than 1.0 to increase the height at which the coarse particles or steel balls fall. Mills as large as 12 m in diameter are now in common use. Despite this increase in height, the velocity of impact is in the range of 10-20 ms-1.  16  2.2.4 Hammer Mills Hammer mills are a common grinding or crushing unit in small-scale operations or in those cases where fine breakage is undesirable. These units generally consist of a horizontal shaft, rotating at high speed within a cylindrical chamber, attached to a disk with a number of swing hammers located on its circumference. The material entering the mill is impacted and broken by the swinging hammers. The broken particles are thrown against the inside surface of the chamber. Hammer mills are used for intermediate to fine crushing and in some cases for ultrafine (grinding) size production. The velocity of the swing hammers is generally in the range of 10 to 50 ms-1 with the major limitation being wear rates and maintenance/replacement requirements.  Figure 10. A laboratory size hammer mill. 2.2.5 Attrition Mills There are two types of attrition mills. One type, called the ring attrition mill, is used in laboratory- scale applications to grind samples to ultra-fine sizes. The unit consists of a cylinder within which a set of smaller cylindrical metal or ceramic rings are rotated. The action of these rings on the base of the cylinder leads to fine grinding of the material. Some commercial-scale versions are also in use. 17   Figure 11. Ring attrition mill.  A second type of attrition mill consists of two grooved flat circular rotating disks that face each other. The disks are either both rotating at high speeds (in opposite directions) or one of them is rotated while the other is fixed. Particles entering through an opening in one of the disks, pass towards the narrow gap between the disks, rubbing between the grooved surfaces and then discharged from the periphery (Sadler III et al., 1974). It is believed this type of milling has a high energy efficiency however, throughput is limited and is mainly used where production of ultra-fines is desired.   Figure 12. Laboratory attrition mill  2.2.6 Rolling Compression Mills Although these types of mills have been around for many years, only recently have they made a resurgence due to the development in the 1960s of high-pressure compression milling. In this type of mill (the term "mill" is used because of the rotating nature of the device, similar to a ball or rod mill), 18  particles are caught and crushed between a roller and a solid surface. Bowl mills and roller mills are both considered rolling compression mills in which a rotating roller moves around the surface of a flat plate or a bowl. Rolling mills are mainly in use in the cement industry where dry grinding is preferred and air can be used to sweep ground particles off the surface of the flat plate or bowl.  2.2.6.1 High Pressure Grinding Rolls (HPGR) Since its commercial introduction in the early 1980s, applications of HPGR have significantly increased in the last few years. HPGR is in wide use in the cement industry, but has had a considerably slower start in the mineral industry mainly due to a perception that wear rates are excessive. Over the last few years the problems with the wear rates have been addressed by the use of advanced wear-resistant materials leading to increased interest in the technology, particularly in copper and iron ore processing (Lim et al., 1997). HPGR offers a higher energy efficiency (about 30%) compared to processes such as semi-autogenous grinding (SAG) and balls mills (Rosario, 2010). It is today viewed as an alternative technology with a realistic potential to reduce comminution energy requirements (Daniel & Morrell, 2004). The cross-section of an HPGR can be seen in Figure 13. Material is drawn from the feeder into the unit by rotating rolls. There are two counter-rolling rolls, with one moving linearly and the other one rotating around a fixed axis. This creates a high compression force leading to inter-particle stresses throughout the particle bed to create particle breakage. High inter-particle stresses result in a greater amount of fines in comparison to other comminution methods according to (D. Fuerstenau et al., 1995).   19    Figure 13. Schematics of HPGR  (Napier-Munn, 1996)  It has been shown that weakening of particles in high-pressure roll grinding together with the HPGR product containing a greater amount of fines compared to other crushing methods leads to energy savings of the order of 20-40% (Tavares, 2005). The product leaves the unit as a compressed cake which must be broken-up for further processing. The energy to do this is relatively low.  2.2.7 Barmac Crusher The Barmac crusher is a type of impact crusher invented in the early 1960s by McDonald and Bartley in New Zealand. It is a high energy centrifugal rock "pump" with a relatively high rotor speed  up to 100 ms-1 tip speed (Hamer, 1998; Rodriguez, 1990). They are most commonly used in the cement and aggregate industries for abrasive materials. Figure 14 illustrates a schematic of a Barmac crusher. 20   Figure 14. Schematic of Barmac crusher operation (Jankovic et al., 2004)  As the feed passes over the distributing plate, it is split into two separate streams. Part of the material passes into the central rotor where it is accelerated by the centrifugal force of the rotor action. The remainder of the material falls vertically in the form of a curtain around the periphery of the chamber. The rotor-accelerated material is driven outward into this curtain where particles meet at high impact velocity in the crushing chamber. This "rock-on-rock" crushing involves a number of fracture modes such as impact, attrition, and abrasion to reduce the material size. The crushed particles discharge through the clearance between the crusher chamber and the rotor wall (Jankovic et al., 2004; Sandvik et al., 1999). Simulation and modeling work have shown that pre-crushing using Barmac crushers or replacement of roller crusher circuits with Barmac crushers can improve energy efficiency of the circuit and reduce operating costs significantly (Jankovic et al., 2004; Sandvik et al., 1999).  21  2.2.8 Jet Milling Jet mills are widely used in industries for ultra-fine grinding of solid materials, a unit operation process where particles are ground to a fineness in which 80% of the particles are smaller than 1-10 µm (Katz & Kalman, 2007). The milling component of a jet mill consists of a chamber and several nozzles. Particles are fed from a nozzle into a spiral opening where they are accelerated by pressurized gas or steam jets entering through other nozzles. The grinding effect is produced by collisions between the particles or by impact against solid surfaces. After breakage, material is classified from the center of the mill outlet (Vogel, 1991). The most significant variables in jet milling are feed rate, volumetric flow rate of air, and the height of the classification tube to provide a constant grinding pressure (Tuunila & Nyström, 1998). Feed rates and mass flow rates of air are the most important factors (Han et al., 2002; Ramanujam & Venkateswarlu, 1969). Figure 15 shows the components and operations of a jet mill (Cino Equipment, n.d.).    Figure 15. Components and operation of a jet mill.   High pressure water jet comminution shows great potential in coal pulverization with low energy consumption and high comminution efficiency and low equipment wear. The technique was first used in the mid-80s to disintegrate organic and non-organic materials, but applications today include coal comminution (Cui et al., 2006; Mazurkiewicz, 1984). The general operation of high pressure water 22  jets is similar to jet-milling with particles obtaining kinetic energy from the water jet, travelling at speeds from 200 to 400 ms−1 before colliding with each other and a target plate (Cui et al., 2006).  23  3 TESTWORK AND PROCEDURE 3.1 Summary  This section of the thesis outlines the testwork procedures used to conduct this research. The physical characteristics of the materials and the methods employed to prepare the samples are presented. The different steps of the experiments and the equipment used are discussed.  3.2 Sample Preparation 8 pieces of Lodestone (magnetite) were purchased from Ward's Natural Science. 6 pieces of these pieces, totaling about 4.5 kg in weight were crushed as shown in Figure 16.  Figure 16. Crushing flowsheet  After crushing, a sieve analysis was performed on the material. Figure 17 shows the graph of cumulative weight percent passing as a function of particle size obtained from this analysis. 10 Mesh Screen 10 Mesh Screen 10 Mesh Screen Crushed Magnetite  Figure  As expected, the size distribution in graph, is approximately linear on a log Figure 18 illustrates the relationship between sample (before impact) as a function of particle size for the SSA (0.78 to 0.8 m2g-1) of magnetite for the relatively large particles (1 to 2mm) this work. For comparison purposes, a of 80 cm2g-1  – a value 100 times less for real-world particles, two orders of magnitude have occurred because of the magnetic properties of magnetite; larger particles attract many dust sized particles to their surface. These tiny particles have an extremely high SSA which gives a false measure of the true SSA for the To verify this theo ample of the 1 to 2 mm size material was washed not stirred – and th ied to ensure that most of the dust subsequent measu significantly lowe 10 100 100 200 Cu m ul at ive  %  P as sin g Size Distribution of the Original Magnetite Sample 50     20 17. Sieve analysis on crushed magnetite the region of interest (from 1mm to 2 mm), as highlighted on the -log graph.  Specific Surface Area (SSA) of the original . Figure 18 indicates an unexpectedly high value spherical grain of magnetite of size 1.5 mm would have a  than this measure. While one would expect to see a higher SSA  seems exorbitant. This discrepancy was believed to larger particles.  with water -like particles were eliminated 400 800 1600 3200 6400 Size (um)  magnetite  involved in  SSA -  – gently shaken,  from a ry, a s en dr rement. The SSA of this washed material was determined to be 0 r than the initial measurement. The amount of dust washed out of the sample was 24 .34 m2g-1, i.e., 25  measured as 3.2%. If the dust has a mean particle size of 0.5 microns, then its theoretical specific surface area is 6.28 m2g-1. Assuming a 100% increase above theoretical (12.56), this gives a calculated specific surface area for the washed 1.5 mm sized magnetite of 0.41 m2g-1 which is close to the measured value of 0.34. The difficulty in isolating the -2+1 mm material from dust-sized particles does not affect the results of this work. The measured SSA gives the correct value before and after impact and the dust-sized particles in each sample remains as part of the sample throughout the experiment and within the final sample as well. All efficiency calculations are based on an accurate measurement of newly created surface area, i.e., the difference between the final and initial surface area of the material.  Figure 18. Specific Surface Area (SSA) of magnetite as a function of particle size  A representative sample of magnetite was prepared and sent for assaying. The results (as shown in Appendix F) show a total iron content of  68% with 24% FeO and 71% in the form of Fe2O3 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 0 500 1000 1500 2000 2500 SS A (m 2 / g) Size (µm) Specific Surface Area of the Original Magnetite Sample Vs. Particle Size `26  indicating about 6% gangue minerals in the sample. So the sample consists of about 77% pure magnetite with about 16% pure hematite. Microscopic analysis shows considerable intergrowth between hematite and magnetite as would be expected of a lodestone sample.     3.3 Experiments 3.3.1 Samples A total of 61 samples of different size distributions and different masses were prepared and impacted at various speeds by projectiles of varying lengths and different materials (steel, aluminum, and quartz glass). Each experiment was referenced using the following naming scheme: [BulletLength][BulletMaterial]-[SampleWeight]Mag[SampleSizeID][ImpactSpeed] Table 2 lists all the experiments that were conducted. Table 2. Summary of all experiments Experiment Type # of Samples Sample ID Bullet Type Sample Mass (g) Size Distribution Base Case 7 1/2"St-10MagAD 1/2" long Steel 10 1 mm – 2 mm Repeatability and Error Minimization 10 1/2"St-10MagA 1/2" long Steel 10 1 mm – 1.2 mm 5 1/2"St-10MagB 1/2" long Steel 10 1.2 mm – 1.4 mm 5 1/2"St-10MagC 1/2" long Steel 10 1.4 mm – 1.68 mm 5 1/2"St-10MagD 1/2" long Steel 10 1.68 mm – 2 mm Sample Size Distribution Effects 3 1/2"St-10MagE 1/2" long Steel 10 500 µm -589 µm 3 1/2"St-10MagF 1/2" long Steel 10 210 µm -300 µm 3 1/2"St-10MagG 1/2" long Steel 10 90 µm -150 µm Sample Mass Effects 3 1/2"St-5MagAD 1/2" long Steel 5 1 mm – 1.2 mm 3 1/2"St-15MagAD 1/2" long Steel 15 1 mm – 1.2 mm Bullet Type Effects 3 1/4"St-10MagAD 1/4" long Steel 10 1 mm – 1.2 mm 3 1"St-10MagAD 1" long Steel 10 1 mm – 1.2 mm 4 1/2"Al-10MagAD 1/2" long Aluminum 10 1 mm – 1.2 mm 4 1/2"Gl-10MagAD 1/2" long Glass 10 1 mm – 1.2 mm  27  Table 3 shows some of the physical characteristics of the material. The initial bulk density was calculated for the +1-2 mm size samples by placing a base case sample into the target chamber and measuring the sample bed depth. The specific surface energy for magnetite is from a literature value (Tromans & Meech, 2002) while the Bond Work Index was measured as described in Appendix C.  Table 3. Physical characteristics of magnetite Specific Gravity (g/cm3) Initial Bulk Density (g/cm3) Specific Surface Energy (Jm-2)* Bond Work Index (kWh/t) 5.15 2.18 6.449 11.3 * (Tromans & Meech, 2002) 3.3.2 Procedure Before and after each experiment, a particle size analysis was performed on each sample using a sieving time of 10 minutes. Each experiment consisted of the steps shown in Figure 19. The specific surface area of the sample was measured using a BET surface area analyzer, then the sample was placed into the CERM3 High-Velocity Impact Facility and impacted using the appropriate projectile. The sample was retrieved, weighed, and its specific surface area measured after impact. 28   Figure 19. Experimental flowchart The energy efficiency of breakage was then calculated using Equation 1:  ηG3=G3100× G123aSSAafter-SSAbefore G123bMsample.SEG373G374MprojectileV2  (1)                                 where: η Gd4c Energy Efficiency (%) SSAafter Gd4c Specific surface area after breakage (m2 gGd57 ) SSAbefore Gd4c Specific surface area before breakage (m2 gGd57 ) Msample Gd4c Mass of sample (g) SE Gd4c Specific surface energy ( J m2Gd57 ) MGb6eGb70Gb6dGb68Gb63Gb61Gb72Gb67Gb6aGb63 Gd4cG3Mass of projectile (g) V Gd4c Speed of projectile ( G749 G74fG3a4 ) Measure Surface Area of sample before crushing Shoot the Sample Measure Surface Area of the crushed sample Analyze 29  All variables were experimentally measured or calculated based on measurements except for the specific surface energy of magnetite which was taken to be 6.449 J/m2 (Tromans & Meech, 2002). It is possible that as particles become smaller, their specific surface energy may increase as edges take on a more important role. However, Tromans and Meech, 2002 showed that this phenomenon does not become significant until the particle size drops below 1 micron. So in these experiments, the assumption that specific surface energy remains independent of particle size is considered reasonable.  3.3.2.1 BET Surface Area Analyzer Since direct measurement of surface energy is not easily done without using calorimetry, the total surface area of each sample before and after crushing was measured to calculate the energy efficiency of the system. Measurements were done using a BET surface analyzer, called the AUTOSORB-1 by Quantachrome Instruments. The equipment operates by measuring the quantity of nitrogen gas adsorbed onto a solid surface at an equilibrium vapor pressure. To obtain the necessary data, the material is placed in a sample cell maintained at a constant temperature and a known quantity of adsorbate gas is added to the cell. As adsorption occurs, the pressure in the sample cell changes until equilibrium is established. The difference between the amount of gas admitted and the amount required to fill the void space around the adsorbent is the amount of gas adsorbed at the equilibrium pressure. Using the Brunauer-Emmett- Teller (BET) (Brunauer et al. 1938) equation, the specific surface area of the sample is determined. For all experiments, nitrogen was used as the adsorbate gas.  3.3.2.2 Impact Testing using the High-Velocity Impact Facility The apparatus used to conduct these experiments and crush the samples is a laboratory scale device designed and built at UBC (S. Sadrai et al., 2006). The apparatus consists of a one-stage gas gun in which air is pressurized to a maximum of 250 psi using an air compressor. The projectile, together with a carrier (or sabot) to ensure that the projectile stays on track, is placed inside one end of a 6 m  long pipe of 25 mm internal diameter, facing a targ is filled with the sample to be impacted and the pipe is evacuated using a vacuum pump. A number of solenoid valves are used to release the compre evacuate the pipe. To shoot the projectile, the solenoid valve that allows compressed air to enter the air chamber is triggered. The released air pushes the projectile assembly down the pipe accelerating it towards the target. About 25 cm before reaching the target, the which stops the sabot thus releasing the projectile with all the associated energy. Using tw laser diode detectors located at fixed positions recorded. This value is used to calculate the actual velocity of the projectile just before it enters the target chamber to impact the sample. After impact, the sample Figure 20 shows the different components of the high v  Figure  Projectile Assembly Electrical Panel Air Compressor 30 et chamber at the opposite end. The target chamber to a level of less than 5 mm Hg ssed air and  diameter of the pipe abruptly changes to 12.7 mm , the projectile is detected and the time of travel  is recovered from the target chamber. elocity impact facility.   20. UBC-CERM3 high velocity impact facility   o sets of  Target Chamber Vacuum Pump 31  4 RESULTS AND DATA ANALYSIS 4.1 Summary  In this section, the results of the experiments performed are presented including the base case  in which 1 to 2 mm size samples are impacted at various speeds by a 12.7 mm length steel projectile.  For all experiments, the size distribution of samples after impact as well as the relationship between energy efficiency and impact velocity is given. For some experiments, the 80% passing size of the product as a function of impact speed, the relationship between the Bond energy and input energy as well as the relationship between energy efficiency and input energy are also shown. In the case of tests done with a glass projectile, the energy recovered into new surfaces in the broken projectile is also presented.  4.2 The Base Case (1/2"St-MagAD Series) The 1/2"St-10MagAD series was used as the base case throughout this research. To prepare a representative sample and avoid potential errors, samples were prepared from each of the size distributions (from A to D) and mixed in the correct proportions to give the total AD sample with a linear relationship on a log-log scale. After breakage, a particle size analysis was conducted on each sample as shown in Figure 21. Note that significant improvement in breakage is observed as the impact speed increases. 32    Figure 21. Particle size analysis for 10 gram 1-2 mm size magnetite samples impacted by 1/2" long steel bullet  Table 4 shows the P80 size, the Bond energy, and the weight percent - 37 µm size particles and weight% -150 µm size particles after impact. Note that the amount of undersize particles in the product significantly increases as the impact speed goes above 200 ms-1. In other words, as the impact speed increases above this value, the amount of fines created in the product substantially increases.  Table 4. P80, Bond energy and weight percent -37 µm material and -150 µm material of the Base Case Sample Speed (ms-1) P80 (µm) Bond Energy (J) - 37 µm Size (Weight%) - 150 µm Size (Weight%) Before Impact 0 1800 0 0 0.0 1/2"St-10MagAD72 72 1462 1.1 0.2 8.9 1/2"St-10MagAD129 129 1265 1.8 0.3 16.2 1/2"St-10MagAD148 148 1064 2.9 0.6 20.1 1/2"St-10MagAD171 171 875 4.2 1.4 28.2 1/2"St-10MagAD201 201 666 6.2 7.0 39.5 1/2"St-10MagAD268 268 313 13.4 45.3 67.4 1/2"St-10MagAD400 400 177 21.0 53.4 78.5 0.1 1.0 10.0 100.0 30 120 480 1920 Cu m ul at ive  P as sin g ( % ) Particle Size (µm) 1/2"St-10MagAD400 1/2"St-10MagAD268 1/2"St-10MagAD201 1/2"St-10MagAD171 1/2"St-10MagAD148 1/2"St-10MagAD129 1/2"St-10MagAD7233  The Bond energy as a function of total input energy is shown in Figure 22. As can be seen, the Bond energy increases as the total input energy increases but appears to level out at high energy levels.   Figure 22. Bond energy as a function of total input energy for the 1/2"St-MagAD Series  During each experiment, some of the sample is unrecovered, which could contribute to experimental error. Table 5 shows the material lost in each experiment.  On average, the material loss is about 1.7% and appears to be randomly distributed as a function of impact speed. Table 5. Material loss during experiments for the 1/2"St-MagAD Series Sample Speed (ms-1) Material Loss (g) Material Loss (%) 1/2"St-10MagAD72 71.8 0.1097 1.10 1/2"St-10MagAD129 128.5 0.3410 3.41 1/2"St-10MagAD148 148.4 0.1242 1.24 1/2"St-10MagAD171 170.9 0.1392 1.39 1/2"St-10MagAD201 200.5 0.1069 1.07 1/2"St-10MagAD268 268.3 0.2113 2.11 1/2"St-10MagAD400 400.0 0.1378 1.38  0 5 10 15 20 25 0 200 400 600 800 1000 Bo nd  En er gy  (J ) Total Input Energy (J)34  Figure 23 presents the energy efficiency as a function of impact speed. As can be seen, the energy efficiency increases as speed increases, but peaks between 250 to 300 ms-1.  At this peak, the efficiency is about four to five times higher than the efficiency at speeds below 100 ms-1.   Figure 23. Energy efficiency as a function of impact speed for magnetite samples with a size distribution of 1 to 2 mm, impacted using 12.7 mm length steel bullets. 4.3 Reproducibility and Error Minimization To examine the reproducibility of these experiments, additional tests were performed on individual samples of a tighter size distribution within the range of 1 to 2 mm. To produce a more precise feed size, 4 sets of samples from this size fraction were prepared with progressively smaller sizes. Ten representative samples of 1 to 1.2 mm size (A series), 5 samples of 1.2 to 1.4 mm size (B series), 5 samples of 1.4 to 1.68 mm size (C series) and 5 samples of 1.68 to 2 mm size (D series) were prepared. The samples were impacted with a 12.7 mm steel bullet at 5 speeds ranging from 100 ms-1 to 350 ms-1. After breakage, a screen analysis was performed on each sample. As can be seen in Figure 24, experiments conducted at similar impact speeds generate almost identical particle size distributions, showing high reproducibility. For all sets, a similar trend to the base case is observed, i.e., as velocity increases, breakage becomes more efficient – the error band is about ±0.1%. 0 1 2 3 4 5 6 0 100 200 300 400 500 Ef fic ie nc y Projectile Speed (ms-1)35    Figure 24. Particle size analysis of 10 gram magnetite samples, impacted by a 12.7 mm length steel bullet, with feed size distributions of a) 1 to 1.2 mm b) 1.2 to 1.4 mm c) 1.4 to 1.68 mm d) 1.68 to 2 mm. 1 10 100 80 320 1280 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) MagA325 MagA313 MagA240 MagA235 MagA177 MagA173 MagA144 MagA143 MagA105 MagA98 1 10 100 30 120 480 1920 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) MagB307 MagB222 MagB186 MagB135 MagB120 10 100 80 640 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) MagC337 MagC268 MagC154 MagC107 MagC127 1.00 10.00 100.00 80 640 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) MagD342 MagD275 MagD193 MagD142 MagD118 (a) (b) (c) (d) 36  The P80, Bond energy, and weight percent -150 µm size particles in the product are shown in Table 6 for each sample. As expected, the P80 is reduced and the amount of undersize particles increases as impact speed increases. Moreover, for similar experiments (experiments with very close impact speeds) the P80 and the amount of undersize particles in the product are similar. Table 6. P80 and weight percent -150 µm material for MagA to MagD Series Sample Speed (ms-1) P80 (µm) Bond Energy (J) - 150 µm Size (Wt. %) 1/2"St-10MagA Series Before Impact 0 1160 0.0 0.0 1/2"St-10MagA98 98 1031 0.7 7.2 1/2"St-10MagA105 105 1007 0.9 8.0 1/2"St-10MagA143 143 863 1.9 12.7 1/2"St-10MagA144 144 852 2.0 13.7 1/2"St-10MagA173 173 629 4.3 32.7 1/2"St-10MagA177 177 605 4.6 31.0 1/2"St-10MagA235 235 366 9.3 56.1 1/2"St-10MagA240 240 348 9.9 59.0 1/2"St-10MagA313 313 221 15.4 74.5 1/2"St-10MagA324 324 207 16.3 76.0 1/2"St-10MagB Series Before Impact 0 1360 0.0 0.0 1/2"St-10MagB120 120 1135 1.0 14.6 1/2"St-10MagB135 135 1026 1.7 27.4 1/2"St-10MagB186 186 684 4.5 42.8 1/2"St-10MagB222 222 476 7.6 53.8 1/2"St-10MagB307 307 264 14.0 71.4 1/2"St-10MagC Series Before Impact 0 1624 0.0 0.0 1/2"St-10MagC107 107 1410 0.7 11.9 1/2"St-10MagC127 127 1252 1.4 15.6 1/2"St-10MagC154 154 996 2.8 27.3 1/2"St-10MagC268 268 302 13.3 68.7 1/2"St-10MagC337 337 224 17.1 75.9 37  1/2"St-10MagD Series Before Impact 0 1936 0.0 0.0 1/2"St-10MagD118 118 1517 1.2 4.3 1/2"St-10MagD142 142 1272 2.2 9.0 1/2"St-10MagD193 193 767 5.4 30.7 1/2"St-10MagD275 275 290 14.6 63.3 1/2"St-10MagD342 342 234 17.4 73.2 The P80s for each of the above experiments are plotted against impact speed in Figure 25. As observed, for impact speeds between 100 to 250 ms-1, the P80 decreases rapidly as impact speed increases, but after 250 ms-1, the rate at which the P80 decreases drops. Note that at speeds above 250 ms-1, the P80 size for all experiments regardless of the original size distribution appears to converge to about 200 µm.   Figure 25. P80 as a function of impact speed for samples with various size distribution (between 1 to 2mm)  Figure 26 shows the Bond energy as a function of impact speed. Note that all results appear to follow a similar trend line simply displaced slightly along the trend line reflecting their different initial particle size. Note as well, that the Bond energy appears to level off at high velocities and high input energy levels. 100 1000 0 100 200 300 400 500 P8 0 (µ m ) Impact Speed (ms-1) 1 - 2 mm 1.68 - 2 mm 1.4 - 1.68 mm 1.2 - 1.4 mm 1 - 1.2 mm38   Figure 26. Bond energy as a function of impact speed for samples with various size distribution (between 1 to 2mm)  A graph of Bond energy as a function of total input energy is presented in Figure 27.   Figure 27. Bond energy as a function of total input energy for samples with various size distribution (between 1 to 2mm)  Energy efficiency as a function of impact speed is given in Figure 28.  A peak efficiency is observed at a speed of about 250 ms-1. The reproducibility of the experiments is clearly apparent. The trend of efficiency as a function of impact speed and the velocity at which the efficiency peaks are similar for all four sets of experiments. 0 2 4 6 8 10 12 14 16 18 20 0 50 100 150 200 250 300 350 400 Bo nd  En er gy  (J ) Speed (ms-1) 1/2"St-10MagA Series 1/2"St-10MagB Series 1/2"St-10MagC Series 1/2"St-10MagD Series 0 2 4 6 8 10 12 14 16 18 20 0 100 200 300 400 500 600 700 800 Bo nd  En er gy  (J ) Total Input Energy (J) 1/2"St-10MagA Series 1/2"St-10MagB Series 1/2"St-10MagC Series 1/2"St-10MagD Series39    Figure 28. Impact efficiency as a function of impact speed for magnetite samples (impacted using a 12.7 mm length steel bullets) with a size distribution of a) 1 to 1.2 mm b) 1.2 to 1.4 mm c) 1.4 to 1.68 mm d) 1.68 to 2 mm. 0 1 2 3 4 5 6 0 50 100 150 200 250 300 350 E f f i c i e n c y Speed (ms-1) 0 1 2 3 4 5 6 0 50 100 150 200 250 300 350 E f f i c i e n c y Speed (ms-1) 0 1 2 3 4 5 6 0 100 200 300 400 E f f i c i e n c y Speed (ms-1) 0 1 2 3 4 5 6 0 100 200 300 400 E f f i c i e n c y Speed (ms-1) (b) (a) (c) (d) 40  4.4 The Effect of Particle Size Distribution  The above experiments raise the question of how the relationship between the energy efficiency and impact speed changes as the feed particle size distribution varies. More specifically, does this trend continue as the feed size becomes finer? To answer this question, another set of experiments was designed with an ever decreasing particle size distribution. A total of 9 representative samples, 3 of 500 to 589 µm size (E series), 3 of 210 to 300 µm size (F series), and 3 of 90 to 150 µm (G series), were prepared and  impacted using a 12.7 mm length steel bullet at speeds ranging from 100 ms-1 to 350 ms-1. Figure 29 shows the results of these tests. As can be seen, better breakage occurs as the impact speed is increased but the effect seems to drop off with decreasing feed particle size. 41   Figure 29. Size analysis for 10g mag. samples impacted by a 12.7 mm long steel bullet, with a feed size distr n of a) 500 to 589 µm b) 210 to 300 µm c) 90 to 150 µm. 1 10 100 30 120 480 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) MagE336 MagE245 MagE163 1 10 100 30 120 480 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) MagF319 MagF224 MagF171 10 100 30 120 480 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) MagG344 MagG236 MagG176 (a) (b) (c) ibutio42  Table 7 contains the P80, Bond energy and weight percent of -37 µm size particles after impact for each sample. As expected, the amount of undersize particles increases as impact speed increases. Moreover, at the same impact speed, the amount of undersize particles in the product is higher when the size of the original sample is smaller. Table 7. P80, Bond energy, and weight percent of - 37 µm material for MagE, MegF and MagG Series Sample Speed (ms-1) P80 (µm) Bond Energy (J) - 37 µm Size (Weight %) 1/2"St-10MagE Series (-589 + 500 microns) Before Impact 0 571 0.0 0.0 1/2"St-10MagE163 163 447 2.2 3.2 1/2"St-10MagE245 245 286 7.0 11.6 1/2"St-10MagE336 336 172 14.0 15.7 1/2"St-10MagF Series (-300 + 210 microns) Before Impact 0 282 0.0 0.0 1/2"St-10MagF171 171 247 1.7 3.6 1/2"St-10MagF224 224 190 5.3 12.7 1/2"St-10MagF319 319 127 11.9 22.8 1/2"St-10MagG Series (-150 + 90 microns) Before Impact 0 138 0.0 0.0 1/2"St-10MagG176 176 127 1.5 15.5 1/2"St-10MagG236 236 106 4.9 27.5 1/2"St-10MagG344 344 77 11.7 33.4 The relationship between the Bond energy and input energy for this series of experiments is shown in Figure 30. Note that the Bond energy appears to increase at a higher rate for samples with the coarsest feed size distributions as a function of total input energy whereas for the finer sized samples the slope appears to remain the same and the Bond energy does not show a leveling off at high energy levels. 43   Figure 30. Bond energy as a function of total input energy for samples  of different size distributions Figure 31 shows how energy efficiency changes as a function of impact speed for four sets of different size distributions. As observed, the trend of each graph is similar, but energy efficiency at a particular impact speed is lower for finer feed size distributions. As well, the point at which energy efficiency peaks appears to increase as feed size decreases. For the G series, the efficiency peaks at 350 ms-1.    Figure 31. Comparison of energy efficiency vs. impact speed for samples of different size distributions  0.0 5.0 10.0 15.0 20.0 25.0 0.0 200.0 400.0 600.0 800.0 1000.0 Bo nd  En er gy  (J ) Total Input Energy (J) 1 to 2 mm 500 to 590 µm 210 to 300 µm 90 to 150 µm 0 1 2 3 4 5 6 0 100 200 300 400 500 Ef fic ie nc y Speed (ms-1) 1 to 2 mm 500 to 590 um 210 to 300 um 90 to 150 um44  The velocity at which efficiency peaks together with the peak efficiency for each set is shown in Table 8.   Table 8. Estimated peak efficiency and velocity for each feed size Feed Size (µm) Peak Velocity (ms-1) Peak Efficiency (%) 1000-2000 240 4.8 500-590 280 4.0 210-300 310 3.4 90-150 350 2.8  4.5 The Effect of Sample Mass A factor that may also affect energy efficiency achieved for a particular impact speed is the weight of the sample (or the bed depth of the target). To investigate this aspect, three 5g and three 15g samples with the same particle size distribution as the base case were prepared. The samples were each impacted by a 12.7 mm length bullet at speeds ranging from 100 to 350 ms-1. Figure 32 shows the particle size distribution of the 5g and 15g samples after impact. As can be seen, at lower speeds (below about 220 ms-1) the amount of breakage observed in the 5g samples is higher than that observed in the 10g samples (base case) at similar speeds. But, at speeds close to 300 ms-1, it appears that better breakage occurs for the 15g samples.  45  Figure 32. Particle size analysis for 5g, 1-2 mm size magnetite samples  Figure 33. Particle size analysis for 15g, 1-2 mm size magnetite samples  impacted by 12.7 mm long steel bullet 1 10 100 30 120 480 1920 Cu m ul at ive  P as sin g ( % ) Particle Size (µm) 1/2"St-5Mag 1/2"St-5Mag 1/2"St-5Mag 0.1 1.0 10.0 100.0 30 120 480 1920 Cu m ul at ive  P as sin g ( % ) Particle Size (µm) 1/2"St-15Ma 1/2"St-15Ma 1/2"St-15Ma (a) (b) AD307  AD205 AD141 g g g AD316  AD206 AD12846  The P80, Bond energy and weight percent of - 37 µm and - 150 µm in the product is shown in Table 9. As expected, the amount of undersize particles increases as impact speed increases. However, at lower speeds (under 210 ms-1), the amount of undersize particles in the product is higher at lower masses. As the speed increases to about 300 ms-1, the amount of these undersize particles for the 5 gram sample is lowest, while the amount of undersize particles for the 10 gram sample is much higher than that of the 15 gram sample.  Figure 34 shows the Bond energy as a function of input energy for samples of different mass. The Bond energy for the 5g samples at constant energy is lower than that of the 10g and the 15g samples. However, the Bond energy of the 10g samples is equal, if not higher, than that of the 15g samples up to an input energy level of ~400 J.  Table 9. P80, Bond energy and weight percent of -37 µm and -150 µm material  for 5MagAD, 10MagAD and 15MagAD Series Sample Speed (ms-1) P80 (µm) Bond Energy (J) - 37 µm Size (Weight %) - 150 µm Size (Weight %) 1/2"St-5MagAD Series Before Impact 0 1800 0.0 0.0 0.0 1/2"St-5MagAD141 141 1068 1.4 7.2 33.1 1/2"St-5MagAD205 205 538 4.0 9.3 46.2 1/2"St-5MagAD307 307 287 7.2 21.2 67.2 1/2"St-10MagAD Series Before Impact 0 1800 0.0 0 0.0 1/2"St-10MagAD72 72 1462 1.1 0.2 8.9 1/2"St-10MagAD129 129 1265 1.8 0.3 16.2 1/2"St-10MagAD148 148 1064 2.9 0.6 20.1 1/2"St-10MagAD171 171 875 4.2 1.4 28.2 1/2"St-10MagAD201 201 666 6.2 7.0 39.5 1/2"St-10MagAD268 268 313 13.4 45.3 67.4 1/2"St-10MagAD400 400 177 21.0 53.4 78.5 1/2"St-15MagAD Series Before Impact 0 1800 0.0 0.0 0.0 1/2"St-15MagAD128 128 1543 1.2 0.3 8.3 1/2"St-15MagAD206 206 916 5.8 4.9 30.2 1/2"St-15MagAD316 316 337 18.9 28.6 63.2   Figure 34. Bond energy as a function of total input energy  Finally, Figure 35 illustrates and compares energy efficiency as a function of impact speed for samples of different mass.  The trends for both series (5g samples and 15 case. However, the 5g series peaks at a lower speed (around 200 ms 300 ms-1. Figure 35. Comparison of energy efficiency vs. impact speed 0 5 10 15 20 25 0 200 400 Bo nd  En er gy  (J ) Total Input Energy (J) 0 1 2 3 4 5 6 0 100 Ef fic ie nc y ( % ) 47  for samples of various masses g samples) are very similar to that of the base -1) while the 15g series peaks at about for samples of different mass 600 800 1000 200 300 400 500 Speed (m/s) 5 gram sample 10 gram Sample 15 gram sample     15 gram samples 10 gram samples 5 gram samples48  4.6 The Effect of Bullet Size and Material This set of experiments used different size bullets so the energy input would be different for the same projectile velocity. As well, different types of bullet materials were tested to investigate further effects of bullet mass at the same velocity. By changing the size or the material of the bullet, we can investigate the effects of input energy on energy efficiency independent of velocity. A total of fourteen 10g samples with a size distribution of 1 to 2 mm were prepared. Three samples were impacted using a 25.4 mm long steel bullet, three were shot using a 6.35 mm long steel bullets, four were done using a 12.7 mm aluminum bullet and four were shot using a 12.7 mm long glass bullet. Figure 36 shows the relationship between energy efficiency as a function of impact speed for different bullet sizes and types.  Figure 36. Size analysis for 1 to 2 mm, 10g magn 1 10 100 30 240 1920 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) 1/4"St-10MagAD347 1/4"St-10MagAD235 1/4"St-10MagAD170 1 10 100 30 240 1920 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) 1"St- 10MagAD287 1"St- 10MagAD213 1 10 100 30 240 C u m u l a t i v e  P a s s i n g  ( % ) Particle Size (µm) 1/2"Al-10MagAD336 1/2"Al-10MagAD272 10 100 P a s s i n g  ( % ) 1/2"Gl- 10MagAD362 (b) (a) 49  etite samples impacted by a) 6.35 mm long steel bullet; b) 25.4 mm long steel bullet; c) 12.7 mm long aluminum bullet; d) 12.7 mm long glass bullet. 1920 1/2"Al-10MagAD205 1/2"Al-10MagAD146 0 1 30 240 1920 C u m u l a t i v e  Particle Size (µm) 1/2"Gl- 10MagAD258 (c) (d) 50  Table 10 summarizes the P80, Bond energy and Weight% -150 µm material in the product for each of the above experiments. As expected, for experiments using steel bullets, the amount of breakage increases when the sample is impacted by a larger bullet. For different materials, breakage with an aluminum bullet is higher than that for the glass bullet, but less than that for the steel bullet. Table 10. P80, Bond energy, and wt% -150 µm material for 6.35mm steel, 25.4mm steel, and 12.7mm Al and glass bullets. Sample Speed (ms-1) P80 (µm) Bond Energy    (J) -150 µm Size Particle (Mass %) 1/4"St-10MagAD Series Before Impact 0 1800 0.0 0.0 1/4"St-10MagAD170 170 1078 2.8 24.9 1/4"St-10MagAD235 235 631 6.6 58.4 1/4"St-10MagAD347 347 244 16.5 74.4 1"St-10MagAD Series Before Impact 0 1800 0.0 0.0 1"St-10MagAD127 127 1044 3.0 21.1 1"St-10MagAD213 213 488 8.8 44.4 1"St-10MagAD287 287 273 15.0 63.3 1/2"Al-10MagAD Series Before Impact 0 1800 0.0 0.0 1/2"Al-10MagAD205 205 784 4.9 38.1 1/2"Al-10MagAD272 272 429 10.1 57.2 1/2"Al-10MagAD336 336 251 16.1 71.2 1/2"Gl-10MagAD Series Before Impact 0 1800 0.0 0.0 1/2"Gl-10MagAD152 152 1646 0.4 2.6 1/2"Gl-10MagAD195 195 1358 1.5 4.8 1/2"Gl-10MagAD258 258 862 4.3 25.7 1/2"Gl-10MagAD362 362 379 11.3 62.2  Figure 37 shows Bond energy as a function of input energy for samples impacted by different bullet types.    51   Figure 37. Comparison of Bond energy as a function of input energy for various bullet types  The relationship of energy efficiency with respect to impact speed for experiments using various bullet dimensions and materials is shown in Figure 38. As can be seen, the energy efficiency peaks at around 200 ms-1 for samples impacted by the 25.4 mm long steel bullet. For the 6.35 mm steel bullet, the efficiency peaks at 350 ms-1. The trend and relationship between the efficiency and the impact speed seems very similar for the 6.35 mm steel bullet series and the 12.7 mm aluminum bullet series which have a similar mass. In the case of glass bullets, the efficiency is much lower than the other cases and the relationship over the range considered appears almost linear, however, the breakage of the bullet is not considered in this diagram. This will be done subsequently.  0 5 10 15 20 25 0 200 400 600 800 1000 Bo nd  En er gy  (J ) Total Input Energy (J) 1/2" Aluminum 1/2" Glass 1/4" Steel 1/2" Steel 1" Steel52   Figure 38. Comparison of energy efficiency vs. impact speed for various bullet types  The type of bullet changes the input energy since the S.G. and mass are different. Figure 39 shows the energy efficiency for the different sets of experiments as a function of input energy. As observed in this graph, experiments with similar input energy lead to similar energy efficiency, although a distinction between the trends of each set can be observed.   Figure 39. Comparison of energy efficiency vs. input energy for various bullet types 0 1 2 3 4 5 6 0 100 200 300 400 500 Ef fic ie nc y ( % ) Speed (ms-1) 1 " Steel 1/2 " Steel 1/4 " Steel 1/2 " Aluminium 1/2" Glass 0 1 2 3 4 5 6 0 200 400 600 800 1000 Ef fic ie nc y Energy (J) 1/2 " Steel 1/2 " Aluminium 1/4 " Steel 1 " Steel 1.2" Glass53  Special consideration must be given to the testwork with glass bullets. As a result of impacting the sample, the glass bullet also breaks and the energy recovered as new surface energy in the bullet particles can be measured. A size analysis was performed on the broken glass after impact. Figure 40 shows the results of this analysis. The trend observed here is similar to that observed for the target sample in that more breakage occurs as impact speed increases.  Figure 40. Sieve analysis performed on glass projectiles after impact  Figure 41 illustrates the efficiency of breakage of samples impacted by glass, the efficiency of glass breakage and the combined efficiency of the system as a function of speed Although the relationship seems linear for the case of magnetite particles impacted by glass bullets for this speed range, the overall efficiency of the system, which is the efficiency of breakage of the sample plus the efficiency of breakage of the bullet, has the same trend as a steel bullet of similar energy with a peak occurring at about 300 ms-1.  0.10 1.00 10.00 100.00 30 120 480 1920 Cu m ul at ive  P as sin g ( % ) Particle Size (µm) Sieve Analysis for Glass Projectile GL362 GL258 GL195 GL15254   Figure 41. Efficiency as a function of impact speed for magnetite samples impacted by glass, glass bullet breakage and the total breakage efficiency 4.7 Specific Surface Area Since the definition of efficiency depends on specific surface area, attention should be given to how this changes with particle size. Four samples impacted at various speeds were selected out of the 12.7 mm long St-MagA series. After impact, these samples were sieved into 3 portions: -37 µm, -150 µm +37 µm and +150 µm. Using the BET surface area analyzer, the specific surface areas of these fractions were measured. A similar analysis was also conducted on the sample before impact. The results of these measurements are summarized in Figure 42.  As can be seen the S.S.A. of each size fraction increases with impact velocity indicating that the surface roughness significantly changes during breakage. This suggests that attrition of ultra-fines from surface on surface interactions becomes greater as impact velocity increases. 0 1 2 3 4 5 6 0 100 200 300 400 Ef fic ie nc y Speed (ms-1) Combined Efficiency Glass Bullet Brakage Sample Impacted by Glass Glass Bullet Bre kage 55    Figure 42. Specific Surface Area (SSA) as a function of impact speed for particle sizes of a) -37 µm b) -150 µm +37 +150 µm   1.64 1.65 1.66 1.67 1.68 1.69 1.70 1.71 0 200 400 600 SS A (m 2 / g) Speed (ms-1) 1.44 1.46 1.48 1.50 1.52 1.54 1.56 1.58 0 200 400 600 SS A (m 2/ g) Speed (ms-1) 0.87 0.88 0.89 0.9 0.91 0.92 0.93 0.94 0.95 0.96 0.97 0 100 200 300 400 500 SS A (m 2 / g) eed (ms-1) (a) (b) (c) Sp  µm c) 56  5 DISCUSSION 5.1 Summary This section discusses the results of the experiments conducted. The separate contribution of input energy and impact speed on improvements in energy efficiency is analyzed. The reproducibility of the results is evaluated and results are compared to those in previous work. Subsequently, an analysis is provided to describe why the energy efficiency peaks at a particular impact speed and how this peak is influenced as a function of particle size distribution and target bed depth. A discussion of the results of the rock-on-rock impact (using glass projectiles to impact magnetite samples) is also provided. Some thoughts on how these results can be used in future work are presented.  5.2 Impact Speed and Input Energy Models The objective of this work was to find a relationship between impact speed and energy efficiency. For the base case, it was observed that energy efficiency can be increased up to about 5%. This is over 3 times the comminution efficiency of conventional equipment. Moreover, during all experiments it is shown that, as speed is increased, the energy efficiency increases to a maximum after which it drops as impact speed is further increased.  For impact speeds ranging from 100 ms-1 to 350 ms-1, two behaviors are observed:  one leading up to the peak efficiency and the second for speeds above this peak.  5.2.1 Impact Speed vs. Input Energy One important question to consider here is "Does the enhancement in energy efficiency result from impact speed or is it a result of input energy?" Both impact speed and energy efficiency could be thought of as reasons for improvement in energy efficiency. In the case of impact speed, similar to what happens during blasting, higher impact speed introduces a shock wave that travels within the particles facilitating crack initiation and faster crack propagation. This results in more efficient breakage of particles. Likewise, in the 57  case of input energy, the number of internal microcracks within particles that would start propagating at the time of impact is directly related to the amount of input energy. However, these two factors may or may not contribute equally. It may even be the case that the contribution of one is insignificant or that there are other factors involved. To investigate the source of improvement in energy efficiency further, a number of experiments with various projectiles having different sizes and materials were conducted, as explained before. Comparing the results obtained from these experiments, the contribution of each of these factors can be analyzed separately. In fact, for a given speed, before the peak is reached, more massive projectiles appear to result in higher efficiencies confirming that the input energy is definitely a contributing factor in its own right. However, this observation is countered when considering the effect of input energy on energy efficiency. The graphs in Figures 43 and 44 compare the samples impacted by the 12.7 mm long aluminum projectile to those impacted by the 12.7 mm long steel projectile. For low input energy and a constant energy input, the energy efficiency is higher for the lower mass projectile meaning that impact speed may play a role independent role of energy. At higher energy input levels, the opposite is true suggesting that the effect of impact velocity increases becomes less at high energy levels.  Figure 43. Comparison of energy efficiency vs. impact speed for various bullet types 0 1 2 3 4 5 0 100 200 300 400 500 Ef fic ie nc y Speed (ms-1) 1/2 " Steel 1/2 " Aluminium58   Figure 44. Comparison of energy efficiency vs. input energy for different bullet types  So although input energy and impact speed both contribute to an improved energy efficiency, their relative contributions are not necessarily equal and may change as impact speed changes. Figure 45 has been drawn to show the family of curves that represent conditions that produce equal energy levels on the efficiency vs. speed graph for various steel projectiles. With this approach, the effects of speed and energy can be separated. The graph shows that despite what was originally expected, at constant energy level, increasing speed does not result in higher efficiencies. In fact, the efficiency obtained at a constant energy level decreases as velocity increases. This shows that the mass of the projectile is the dominant factor which results in improved efficiencies as more input energy is applied. It is important to note, however, that impact speed still has a positive effect on efficiency but through increased input energy.    0 1 2 3 4 5 0 200 400 600 800 1000 Ef fic ie nc y Energy (J) 1/2 " Steel 1/2 " Aluminium59   Figure 45. Energy efficiency as a function of impact velocity for various constant energy inputs. 5.2.2 Energy of the New Surface Area To further investigate the effects of impact speed and input energy, it is important to look at the relationship between the created surface energy through impact as a function of these variables, as this is a measure of how much breakage occurs during impact. Figure 46 plots total energy of the created surface through each experiment as a function of input energy for various projectiles impacting samples of 1-2 mm size distributions. This graph confirms that more breakage occurs (i.e. more surface area is created) as input energy increases. Moreover, this graph shows that the variations among experiments with projectiles of different masses are not significant. In other words, a particular input energy generates a particular amount of new surface area regardless of the mass and speed of the projectile.  60   Figure 46. Graph of energy of generates surface area as a function of input energy for various bullet types  Figure 47 plots all points obtained from experiments involving samples of 1 - 2 mm size distribution on one graph. At low energy input levels, the graph is relatively flat, since very low input energies simply do not result in breakage. However as input energy increases, there comes a point at after which further increases in input energy do not produce the same efficiency and si the energy recovered begins to level off. The best fit to this data is a third order empirical polynomial equation of the form:  G727Gb57 Gd4c G83G8Gb67Gb6c Gb37 Gd45 G84G8Gb67Gb6c Gb36 Gd45 G85G8Gb67Gb6c (2) where a, b and c are three constants that change as a function of physical properties of the sample. 0 5 10 15 20 25 30 35 40 45 0 200 400 600 800 1000 En er gy  o f t he  su rfa ce  cr ea te d (J) Input Energy (J) 1" steel 1/2" steel 1/4" steel 1/2" Aluminum61   Figure 47. Polynomial fit representing energy of new surface area as a function of input energy  5.2.3 Error Minimization Previous work reported the relationship between impact speed and energy efficiency for three minerals (rock salt, quartz and limestone). Similar to the results for magnetite samples, previous work indicated significant improvements in energy efficiency (of the order of 3 to 5%) as a function of impact speed. Moreover, it was concluded that improvement in energy efficiency was a combined effect of increased impact speed and increased input energy. The objective of this work was to ensure that a minimum error on each test was achieved with error minimized to a point where experiments are reproducible to a reliable value with the existence of a peak clearly observed. This has been achieved with an error on similar tests of ± 0.3%. 5.2.4 Reproducibility To demonstrate the reproducibility of the results and to minimize the errors associated with having a large sample size distribution, experiments in Section 4.3 were designed. If all 26 points obtained with a sample size distribution between 1 to 2 mm (results of sections 4.2 and 4.3) are plotted on one graph (Figure 48), it  can be observed that a similar trend as those found for individual sets of experiments is found. that the experimental error is very small. Figure 48. Reproducibility of experiments on all samples with particles between 1 to 2 mm in size impacted by steel bullets  5.3 Bond Efficiency The Bond energy method is used widely in mining and mineral processing as an important design criterion in determining energy requirements of comminution equipment Figure 49 shows the graph of efficiency as calculated using the Bond equation as a function of for all experiments in which steel projectiles was used to impact 1 to 2 mm samples. figure, the Bond efficiency peaks at around the same speed, as well. about 3%. Bond's method relies on the P80 of the sample rather than the whole size distribution provides no information on the amount and though, the majority of the surface area of a sample is within its finer particles. calculated using the Bond method will always be It is important to note that this is still a considerable improvement to efficiencies obtained in conventional equipment since typical Bond efficiencies are of the order of 1% 0 1 2 3 4 5 6 0 100 Ef fic ie nc y 62  .   According to this  However, the peak efficiency is only characteristics of fines and ultra-fines within the sample For this reason, efficiency  lower than one calculated using the surface area method. .  200 300 400 500 Projectile Speed (ms-1) This shows   projectile . Thus, it even  Figure 49. Bond efficiency  5.4 The Peak Tied to the main objectives of this study, the existence of a peak has question now becomes, what causes thi must consider what happens within the chamber during impact. particles begin to break. At the same time, space between the particles. The existence of void s particles to enter. Without this space, even if enough energy is supplied the daughter particles cannot be created, heat. As particles continue to break, the voidage space becomes filled until there is no further compaction possible. This occurs at a void space of about 22%. The increase in input energy will improve the efficiency of breakage but up to a cert the maximum compaction for the sample is reached and more of the add heat. This is the point at which maximum energy effic impact speed increases. However, sieve analysis results 0.0% 0.5% 1.0% 1.5% 2.0% 2.5% 3.0% 3.5% 4.0% 0 50 100 Bo nd  Ef fic ie nc y 63  as a function of projectile speed  now been clearly identified s peak and can it be manipulated or eliminated? To answer this When the projectile hits the sample  the bulk material begins to compact thus reducing the pace is essential to ensure free space exists that should break the energy will simply move through the mass and  ain point, after which ed input energy will iency occurs and after which efficiency reduces suggest that, although energy efficiency does not 150 200 250 300 350 Projectile Speed (ms-1)  . The , one  void for broken the particles, if dissipate as dissipate as  as 400 45064  improve after the peak efficiency, significant breakage still occurs. The breakage mode after the point of maximum compaction is mainly attrition, since the particles have very little void space that they can break into. So the majority of the breakage results in ultra-fine particles. As discussed previously, the finer the particles, the harder to break them because of a dirth of micro-cracks and the ever increasing loss of void space.  5.4.1 Effect of Particle Size Distribution Experiments were conducted on samples of four distinct size distributions to investigate the effects of particle size distribution on the relationship between energy efficiency and impact speed. Results show that for finer feed particle sizes, a particular impact speed results in lower energy efficiencies. This behavior is expected because as particles get smaller, they become more resistant to breakage, since finer materials contain less inherent flaws. Moreover, as observed, the impact speed which produces the maximum efficiency is higher for finer particles. In fact, for particles finer than 300 µm (the two smallest sets) a peak is not reached within the range of the study. This is because compaction of finer particles to the limit of 22% voids requires a much higher force (or speed).  5.4.2 Effect of Sample Mass The results for samples of various masses indicate that for a particular impact speed, the more massive the sample, the lower the obtained energy efficiency. In our experiments, changing the amount of sample changes the bed depth. This means that more mass requires much more energy input for all of its particles to break. In regards to the location of the peak, as observed, the peak is obtained at a higher velocity for heavier samples. To reach maximum compaction with more mass or a deeper bed, more input energy is required. 65  Figure 50 shows the graph of efficiency as a function of normalized energy (energy per sample mass). In this figure, the behavior of the 5 gram and 10 gram series are similar. For these samples, the efficiency is higher than that of 15 gram samples at a particular energy level.    Figure 50. Efficiency as a function of energy per mass for samples of various masses  Furthermore, with further increases in impact speed, the energy efficiencies for all sets appear to converge to a similar value (~3.5%), (see Figure 35).  5.5 Rock-on-Rock Breakage Special consideration must be given to the experiments involving glass projectiles since they provide information about rock-on-rock impact in which both target and projectile particles may break. The efficiency of fragmentation in the magnetite sample is less than that obtained when the sample is impacted by other projectiles. In addition, there was considerable breakage observed within the projectile itself. When the efficiency of the projectile breakage is combined with the efficiency of fragmentation of the sample, an overall combined energy efficiency is attained. This overall efficiency has a similar trend to the one observed in experiments where an unbreakable projectile is used under similar conditions.  0.00 1.00 2.00 3.00 4.00 5.00 6.00 0.00 20.00 40.00 60.00 80.00 100.00 120.00 Ef fic ie nc y Energy / mass (J/g)) 10 gram Sample 5 gram sample 15 gram sample66  Figure 51 compares the combined efficiency with that obtained with the base case. Although, the trends are similar, there are two main differences. First, the peak efficiency is slightly higher than that of the base case. This takes place because the energy is dissipated through breakage of the projectile during the process of compaction of the target sample. For unbreakable projectiles, all the kinetic energy applied to the projectile is dissipated as heat and sound and does not contribute to the overall breakage. Secondly, the peak efficiency occurs at a higher speed. This happens because the breakage of the projectile provides some void space for particles to break into. Hence a higher amount of input energy is required to achieve maximum compaction.  Figure 51. Comparison of the combined efficiency during impact by glass wit  5.6 A Modified Barmac Crusher The main aim of this project was to investigate and prove that high impact speed improvements in energy efficiency. As a result, it was identified that there exists the energy efficiency of comminution is maximized. It should be noted that prov itself is a very energy intensive process and may not be cost-effective. Moreover 0 1 2 3 4 5 6 0 100 200 300 400 500 Ef fic ie nc y Speed (m/s) Combined Glass Efficiency B Glass (Combined E fect)  h the base case  results in significant  an impact speed at which iding high impact speeds , operating costs of a ase Case67  machine that provides such comminution techniques, especially in regards to wear rates, should be considered. As this thesis is focused on investigating the relationship between comminution efficiency and impact speed and since there is no equipment in which material is impacted by speeds up to 350 ms-1 (other than high-pressure water jet breakage), as a thought-experiment, this section investigates the power requirements of a modified Barmac crusher which could accommodate particle impacts at these speeds. The Barmac unit was chosen as it has the attributes that could achieve such velocities without significant increase in wear rates assuming the mechanical issues of vibration can be dealt with. The power requirements of a crusher with a cylindrical rotor of a given height (h) and diameter (D), which accelerates rock particles to a certain speed (V) at the tip of the rotor, is given by the following equation:  Power = πG376 ρGb70G8aG7G19Gb37 (3)  where ρr is the density of the rotor. Moreover, the total production of such a crusher (in tph) with a number of discharge slots (n) is given by the following equation:  Production = 600G24e G373 Gd46 G88Gb74G88 ρG90G95Gb6eG8aG19 (4)  G88Gb74 Gd4c Void fraction  G88 Gd4c Fraction of ore through rotor ρ = ore density ( t m3Gd57 ) G95Gb6e Gd4c Particle size (m) Thus, a rotor made out of steel with a diameter of 0.3 m and a height of 0.1 m will require 5 MW to accelerate particles to 300 ms-1. The production for such a crusher, with 8 discharge slots, crushing 2 mm size silicate or limestone rock in which 25% of the ore goes through the rotor with a void fraction of 90% 68  is calculated as 850 tph. For such a system, the energy use is about 6 kWh/t. According to the general Bond equation, for material with a Bond Work Index of 12.0 kWh/t, the product size would be 150 µm. If the efficiency of crushing were to be doubled, then one would expect the product size to decrease further to 108 µm. If it were to be tripled, the product size would be 41 µm.  It should be noted that the Barmac crusher actually works on material of about 10-20 mm in size and reduces it to a P80 size of around 7 mm at a rotor tip speed of about 70 ms-1. The available ratings of current Barmac crushers are very different than calculated here. For example, the B9100SE VSI crusher, manufactured by Metso (http://www.metso.com), has an installed power of 600 kW and provides a capacity of 775 tph when the tip speed is 70 ms-1. The crusher has a 0.4 m rotor and is generally used to crush 10 to 20 mm size samples. However, the proposed modification is possible by replacing the rotor with a smaller one and investing in a more powerful motor.  It is also interesting to note that a typical sample size distribution after breakage using a Barmac crusher (as shown in Figure 52) is similar in shape to that obtained in our experiments at low velocities albeit at an order of magnitude difference (see Figure 21, for example).  69   Figure 52. Size distribution of a crushed iron ore sample using a Barmac Crusher (tip speed: 63 ms-1 ) (Metso Minerals Limited)  70  6 CONCLUSIONS AND RECOMMENDATIONS This research has investigated the influence of high speed impact on rock fragmentation and energy efficiency of comminution. The separate effects of input energy and impact speed were examined. Using a high velocity impact laboratory facility, experiments on magnetite samples of various masses and size distributions, impacted by different masses and types of projectiles were performed and analyzed at projectile speeds ranging from 100 ms -1 to 400 ms -1. Before and after each experiment, the specific surface area of the sample was measured and the energy efficiency of breakage was calculated. The results prove that the energy efficiency of rock fragmentation can be improved to a level of 5% as a result of high speed impact.  6.1 Conclusions The following conclusions result from this research: • Energy efficiency in rock fragmentation can be increased to 5% in comparison to conventional comminution equipment at 1-2% through application of high-velocity impact. • This improved efficiency results from two factors: high rate of input energy and high impact speed, both of which have significant contributions. • The results indicate that energy efficiency peaks at an impact speed of 225 to 250 ms-1. At this point the sample has been compacted to its maximum limit after which higher input energy does not result in further efficiency improvement. • If this point of maximum compaction could be eliminated, higher efficiencies may be possible. • The overall trend in the relationship between energy efficiency and impact speed is conserved regardless of the length of the target bed, size distribution of the sample, or type of projectile.  • The larger the length of the target bed is, the lower the efficiency of breakage at any particular impact speed.  71  • The smaller the size of the particles in the sample is, the lower efficiency of breakage will be at a particular speed. For example, the maximum efficiency achieved with a sample having a size of 280 µm was only 3% compared to the 5% efficiency achieved with 1.8 mm samples. • Utilization of more massive projectiles results in higher energy efficiencies at any impact speed. • During rock-on-rock impacts, where both particles break, higher overall efficiencies can be expected. 6.2 Future Work The results of this research prove that high velocity impact has significant implication in mining and mineral processing. However, there is still much work to do in applying this technique to achieve the main vision of the research, i.e., to reduce energy requirements in comminution. In this section, some recommendations on the direction of the future work are outlined: 6.2.1 Enhancement of the Quality of Research While the high velocity impact facility was central to conducting this research, there are some limitations in its use. It is recommended that improvements be done on the facility to enable studying other velocity regimes (an order of magnitude higher). The inspiration behind this work comes from what happens during blasting, but because of the limitation of the facility, we cannot study the effect of velocities higher than 400 ms-1. Moreover, during the experiments, some sample material is lost. Although, the weight percent of these particles are low, their contribution to the overall specific surface area is very significant. Essentially, most of these particles are very fine particles (or dust) that simply cannot be collected after impact. Thus, using a dust collection technique is recommended. Probably the most important modification that could result in remarkable findings should attempt to eliminate the peak efficiency. As discussed, the existence of the peak is a result of a limitation of the 72  apparatus as insufficient space exists into which new particles can move into during breakage at high impact speeds. There are many ways to implement this modification and a recommendation is given in Appendix E which involves redesigning the target chamber. Elimination of the peak point where maximum compaction occurs will mean that further increases in energy efficiency may be possible at higher speeds.  Throughout the experiments, it became apparent that knowledge about how the system behaves at and immediately after the moment that the projectile comes into contact with the sample would enhance our understanding of how particle breakage occurs and how energy is expended. More specifically, identifying and monitoring the location of the projectile as a function of time would enable us to calculate how much force is exerted on the sample as comminution ensues. 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Of 29th Conference on Explosives and Blasting Technique, Nashville, TN.    78  APPENDIX A: EFFICIENCY CALCULATIONS  Before Impact  After Impact  Sample SSA (m2/g) Sample Mass (g) Total Area (m2) Speed (m/s) SSA (m2/g) Sample Mass (g) Input Energy (J) Total Area (m2) Efficiency (%) 1/2"St-10MagA Series 10MagA173 0.817 9.9958 8.1666 173.0 0.910 9.9409 172.06 9.046 3.47 10MagA177 0.813 9.9898 8.1217 176.6 0.915 9.8603 179.31 9.017 3.60 10MagA143 0.778 9.9923 7.7740 142.6 0.819 9.9874 116.86 8.180 2.26 10MagA144 0.810 9.9983 8.0986 143.5 0.853 9.9374 118.41 8.477 2.33 10MagA235 0.821 9.9983 8.2086 234.8 1.041 9.8249 317.07 10.223 4.39 10MagA240 0.808 9.9983 8.0786 239.6 1.037 9.8762 330.16 10.242 4.42 10MagA313 0.802 9.9983 8.0186 312.9 1.170 9.9032 563.09 11.590 4.18 10MagA324 0.818 9.9983 8.1786 324.3 1.207 9.8876 604.56 11.934 4.10 10MagA98 0.799 9.9983 7.9886 98.1 0.811 9.7918 55.30 7.937 1.32 10MagA105 0.822 9.9983 8.2186 104.8 0.836 9.8256 63.17 8.215 1.41 1/2"St-10MagB Series 10MagB307 0.762 9.9962 7.6171 307.3 1.111 9.9268 542.84 11.029 4.12 10MagB222 0.793 10 7.9300 221.5 0.979 9.9491 282.14 9.740 4.23 10MagB135 0.788 9.9999 7.8799 134.9 0.818 9.7829 104.59 8.002 1.81 10MagB186 0.835 9.9875 8.3396 186.1 0.944 9.792 199.10 9.244 3.46 10MagB120 0.800 10.0017 8.0014 119.7 0.821 9.8233 82.41 8.065 1.61 Projectile mass 11.5 g Specific Surface Energy 6.449 Jm-2 79   Before Impact  After Impact  Sample SSA (m2/g) Sample Mass (g) Total Area (m2) Speed (m/s) SSA (m2/g) Sample Mass (g) Input Energy (J) Total Area (m2) Efficiency (%) 1/2"St-10MagC Series 10MagC127 0.778 10.0059 7.7846 127.4 0.812 9.6852 93.36 7.864 2.27 10MagC337 0.798 9.9925 7.9740 337.2 1.230 9.8437 653.67 12.108 4.20 10MagC154 0.756 9.9945 7.5558 153.8 0.820 9.8758 135.98 8.093 2.97 10MagC268 0.841 9.9912 8.4026 267.9 1.157 9.7138 412.63 11.234 4.79 10MagC107 0.755 9.9973 7.5480 107.2 0.771 9.8652 66.14 7.606 1.54 1/2"St-10MagD Series 10MagD342 0.780 9.9974 7.7980 342.1 1.244 9.8947 672.89 12.309 4.40 10MagD193 0.766 9.9862 7.6494 193.1 0.897 9.6977 214.47 8.697 3.81 10MagD118 0.756 9.9995 7.5596 118.1 0.780 9.9224 80.25 7.736 1.88 10MagD142 0.820 9.987 8.1893 142.3 0.864 9.8089 116.43 8.477 2.40 10MagD275 0.778 9.9995 7.7796 275.1 1.105 9.9408 435.13 10.980 4.81 1/2"St-10MagE Series 10MagE336 0.829 9.9996 8.2897 335.7 1.239 9.7873 647.93 12.1264647 3.99 10MagE254 0.888 9.9977 8.8780 245.4 1.097 9.7829 346.30 10.7318413 3.81 10MagE163 0.862 9.9994 8.6195 162.8 0.902 9.8287 152.44 8.8654874 1.66 1/2"St-10MagF Series 10MagF319 1.023 10.0017 10.2317 318.8 1.333 9.9246 584.50 13.2294918 3.39 10MagF224 1.069 9.9982 10.6881 224.4 1.203 9.8333 289.67 11.8294599 2.93 10MagF171 1.024 9.9973 10.2372 170.5 1.058 9.7781 167.09 10.3452298 1.28 Projectile mass 11.5 g Specific Surface Energy 6.449 Jm-2 80   Before Impact  After Impact  Sample SSA (m2/g) Sample Mass (g) Total Area (m2) Speed (m/s) SSA (m2/g) Sample Mass (g) Input Energy (J) Total Area (m2) Efficiency (%) 1/2"St-10MagG Series 10MagG344 1.412 10.0014 14.1220 344.0 1.718 9.9563 680.50 17.1049234 2.89 10MagG176 1.362 9.9972 13.6162 176.4 1.393 9.9595 178.90 13.8735835 1.11 10MagG236 1.366 9.9992 13.6589 236.3 1.473 9.7476 321.01 14.3582148 2.10 1/2"St-10MagAD Series 10MagAD268 0.789 9.999 7.8892 268.3 1.095 9.7877 413.94 10.718 4.67 10MagAD72 0.793 9.9991 7.9293 71.8 0.797 9.8894 29.60 7.885 0.93 10MagAD400 0.740 9.9994 7.3996 400.0 1.309 9.8616 920.00 12.909 3.93 10MagAD171 0.800 9.9988 7.9990 170.9 0.889 9.8596 167.84 8.762 3.36 10MagAD201 0.756 9.9942 7.5556 200.5 0.912 9.8873 231.21 9.017 4.30 10MagAD129 0.790 9.9983 7.8987 128.5 0.817 9.6573 94.94 7.890 1.77 10MagAD148 0.818 9.9994 8.1795 148.4 0.865 9.8752 126.62 8.542 2.36 1/2"St-15MagAD Series 15MagAD316 0.787 15.0089 11.8120 316.2 0.978 14.7238 574.84 14.3998764 3.16 15MagAD206 0.788 15.0057 11.8245 205.7 0.845 14.774 243.22 12.48403 2.23 15MagAD128 0.803 15.0068 12.0505 128.2 0.811 14.7668 94.47 11.9758748 0.81 1/2"St-5MagAD Series 5MagAD307 0.808 5.004 4.0436 307.3 1.527 4.8722 542.84 7.4398494 4.16 5MagAD205 0.771 5.0036 3.8578 205.1 1.147 4.9117 241.91 5.6337199 4.92 5MagAD141 0.788 5.0032 3.9425 140.7 0.923 4.9326 113.86 4.5527898 3.77 Projectile mass 11.5 g Specific Surface Energy 6.449 Jm-2    81   Before Impact  After Impact  Sample SSA (m2/g) Sample Mass (g) Total Area (m2) Speed (m/s) SSA (m2/g) Sample Mass (g) Input Energy (J) Total Area (m2) Efficiency (%) 1/2"Al-10MagAD Series 10MagAD336 0.803 9.9968 8.0274 336.4 0.924 9.78 227.49 9.037 3.35 10MagAD273 0.806 10.0012 8.0610 272.6 0.884 9.587 149.40 8.475 3.23 10MagAD205 0.776 10.0012 7.7609 205.4 0.813 9.8957 84.79 8.045 2.78 10MagAD146 0.789 10.001 7.8908 146.0 0.797 9.8387 42.83 7.841 1.19 Projectile mass 4.02 g Specific Surface Energy 6.449 Jm-2  Before Impact  After Impact  Sample SSA (m2/g) Sample Mass (g) Total Area (m2) Speed (m/s) SSA (m2/g) Sample Mass (g) Input Energy (J) Total Area (m2) Efficiency (%) 1/4"St-10MagAD Series 10MagAD347 0.769 10.0005 7.6904 347.2 0.961 9.8761 346.48 9.491 3.53 10MagAD235 0.801 10.0014 8.0111 235.2 0.883 9.8034 159.02 8.656 3.26 10MagAD170 0.794 10.0006 7.9405 169.7 0.823 9.8231 82.80 8.084 2.22 Projectile mass 5.75 g Specific Surface Energy 6.449 Jm-2  Before Impact  After Impact  Sample SSA (m2/g) Sample Mass (g) Total Area (m2) Speed (m/s) SSA (m2/g) Sample Mass (g) Input Energy (J) Total Area (m2) Efficiency (%) 1"St-10MagAD Series 10MagAD127 0.797 10.0019 7.9715 127.4 0.934 9.8829 186.73 9.231 4.68 82  10MagAD213 0.762 10.0006 7.6205 213.4 1.167 9.8815 523.93 11.532 4.93 10MagAD287 0.787 10.0011 7.8709 286.5 1.461 9.8476 943.72 14.387 4.54 Projectile mass 23 g Specific Surface Energy 6.449 Jm-2  Before Impact  After Impact  Sample SSA (m2/g) Sample Mass (g) Total Area (m2) Speed (m/s) SSA (m2/g) Sample Mass (g) Input Energy (J) Total Area (m2) Efficiency (%) 1/2"Gl-10MagAD Series 10MagAD195 0.808 10.0041 8.0833 194.9 0.818 9.9241 63.05 8.118 1.02 10MagAD362 0.796 9.9986 7.9589 362.0 0.868 9.8604 217.53 8.559 2.10 10MagAD258 0.787 10.0022 7.8717 257.9 0.813 9.7812 110.38 7.952 1.49 10MagAD152 0.792 10.0018 7.9214 151.8 0.795 9.8246 38.25 7.811 0.50 Projectile mass 3.32 g Specific Surface Energy 6.449 Jm-2  Before Impact  After Impact  Sample SSA (m2/g) Sample Mass (g) Total Area (m2) Speed (m/s) SSA (m2/g) Sample Mass (g) Input Energy (J) Total Area (m2) Efficiency (%) 1/2"Al-10MagAD Series Glass195 0.000507 3.32 0.0017 194.9 0.143 3.0851 63.05 0.441 2.09 Glass362 0.000507 3.32 0.0017 362.0 0.659 2.7273 217.53 1.797 2.48 Glass258 0.000507 3.32 0.0017 257.9 0.385 3.2145 110.38 1.238 3.36 Glass152 0.000507 3.32 0.0017 151.8 0.051 3.1568 38.25 0.161 1.25 Projectile mass 3.32 g Specific Surface Energy 6.449 Jm-2 83  APPENDIX B: SIEVE ANALYSIS RESULTS 1/2"St-10MagA98 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 2.31 23.67 100.00 20 0.850 -1000 +  850 1000 1.28 13.11 76.33 25 0.710 -  850 +  710 850 1.23 12.60 63.22 30 0.589 -  710 +  589 710 0.75 7.68 50.61 35 0.500  - 589 +  500 589 0.68 6.97 42.93 40 0.425 -  500 +  425 500 0.70 7.17 35.96 50 0.300 -  425 +  300 425 1.00 10.25 28.79 100 0.150 -  300 +  150 300 1.11 11.37 18.55 170 0.090 -  150 +  90 150 0.45 4.61 7.17  0.000 -90 90 0.25 2.56 2.56 Total 9.76 100.00  1/2"St-10MagA105 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 2.03 20.78 100.00 20 0.850 -1000 +  850 1000 1.54 15.76 79.22 25 0.710 -  850 +  710 850 1.11 11.36 63.46 30 0.589 -  710 +  589 710 0.82 8.39 52.10 35 0.500  - 589 +  500 589 0.71 7.27 43.71 40 0.425 -  500 +  425 500 0.72 7.37 36.44 50 0.300 -  425 +  300 425 0.96 9.83 29.07 100 0.150 -  300 +  150 300 1.10 11.26 19.24 170 0.090 -  150 +  90 150 0.39 3.99 7.98  0.000 -90 90 0.39 3.99 3.99 Total 9.77 100.00    84  1/2"St-10MagA143 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 0.64 6.51 100.00 20 0.850 -1000 +  850 1000 1.45 14.75 93.49 25 0.710 -  850 +  710 850 1.23 12.51 78.74 30 0.589 -  710 +  589 710 0.87 8.85 66.23 35 0.500  - 589 +  500 589 0.79 8.04 57.38 40 0.425 -  500 +  425 500 0.63 6.41 49.34 50 0.300 -  425 +  300 425 1.19 12.11 42.93 100 0.150 -  300 +  150 300 1.78 18.11 30.82 170 0.090 -  150 +  90 150 0.61 6.21 12.72  0.000 -90 90 0.64 6.51 6.51 Total 9.83 100.00  1/2"St-10MagA144 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 0.65 6.62 100.00 20 0.850 -1000 +  850 1000 1.33 13.54 93.38 25 0.710 -  850 +  710 850 1.41 14.36 79.84 30 0.589 -  710 +  589 710 0.71 7.23 65.48 35 0.500  - 589 +  500 589 0.77 7.84 58.25 40 0.425 -  500 +  425 500 0.47 4.79 50.41 50 0.300 -  425 +  300 425 1.31 13.34 45.62 100 0.150 -  300 +  150 300 1.82 18.53 32.28 170 0.090 -  150 +  90 150 0.78 7.94 13.75  0.000 -90 90 0.57 5.80 5.80 Total 9.82 100.00     85  1/2"St-10MagA173 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 0.18 1.83 100.00 20 0.850 -1000 +  850 1000 0.61 6.19 98.17 25 0.710 -  850 +  710 850 0.74 7.51 91.99 30 0.589 -  710 +  589 710 0.66 6.69 84.48 35 0.500  - 589 +  500 589 0.57 5.78 77.79 40 0.425 -  500 +  425 500 0.42 4.26 72.01 50 0.300 -  425 +  300 425 1.19 12.07 67.75 100 0.150 -  300 +  150 300 2.27 23.02 55.68 170 0.090 -  150 +  90 150 1.13 11.46 32.66  0.000 -90 90 2.09 21.20 21.20 Total 9.86 100.00  1/2"St-10MagA177 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 0.22 2.24 100.00 20 0.850 -1000 +  850 1000 0.55 5.59 97.76 25 0.710 -  850 +  710 850 0.59 6.00 92.17 30 0.589 -  710 +  589 710 0.70 7.11 86.18 35 0.500  - 589 +  500 589 0.56 5.69 79.07 40 0.425 -  500 +  425 500 0.36 3.66 73.37 50 0.300 -  425 +  300 425 1.20 12.20 69.72 100 0.150 -  300 +  150 300 2.61 26.52 57.52 170 0.090 -  150 +  90 150 1.31 13.31 31.00  0.000 -90 90 1.74 17.68 17.68 Total 9.84 100.00     86  1/2"St-10MagA235 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 0.22 2.26 100.00 20 0.850 -1000 +  850 1000 0.29 2.98 97.74 25 0.710 -  850 +  710 850 0.30 3.08 94.76 30 0.589 -  710 +  589 710 0.15 1.54 91.68 35 0.500  - 589 +  500 589 0.39 4.01 90.13 40 0.425 -  500 +  425 500 0.20 2.06 86.13 50 0.300 -  425 +  300 425 0.84 8.63 84.07 100 0.150 -  300 +  150 300 1.88 19.32 75.44 170 0.090 -  150 +  90 150 1.92 19.73 56.12  0.000 -90 90 3.54 36.38 36.38 Total 9.73 100.00  1/2"St-10MagA240 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 0.23 2.34 100.00 20 0.850 -1000 +  850 1000 0.25 2.54 97.66 25 0.710 -  850 +  710 850 0.27 2.74 95.12 30 0.589 -  710 +  589 710 0.15 1.52 92.38 35 0.500  - 589 +  500 589 0.35 3.56 90.85 40 0.425 -  500 +  425 500 0.24 2.44 87.30 50 0.300 -  425 +  300 425 0.78 7.93 84.86 100 0.150 -  300 +  150 300 1.76 17.89 76.93 170 0.090 -  150 +  90 150 2.00 20.33 59.04  0.000 -90 90 3.81 38.72 38.72 Total 9.84 100.00     87  1/2"St-10MagA313 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 0.14 1.42 100.00 20 0.850 -1000 +  850 1000 0.16 1.62 98.58 25 0.710 -  850 +  710 850 0.16 1.62 96.96 30 0.589 -  710 +  589 710 0.09 0.91 95.34 35 0.500  - 589 +  500 589 0.22 2.23 94.43 40 0.425 -  500 +  425 500 0.13 1.32 92.20 50 0.300 -  425 +  300 425 0.47 4.76 90.88 100 0.150 -  300 +  150 300 1.15 11.65 86.12 170 0.090 -  150 +  90 150 1.34 13.58 74.47  0.000 -90 90 6.01 60.89 60.89 Total 9.87 100.00  1/2"St-10MagA325 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 16 1.200 -1400 + 1200 1400 0.00 0.00 100.00 18 1.000 -1200 + 1000 1200 0.14 1.42 100.00 20 0.850 -1000 +  850 1000 0.16 1.63 98.58 25 0.710 -  850 +  710 850 0.17 1.73 96.95 30 0.589 -  710 +  589 710 0.15 1.53 95.22 35 0.500  - 589 +  500 589 0.14 1.42 93.69 40 0.425 -  500 +  425 500 0.15 1.53 92.27 50 0.300 -  425 +  300 425 0.41 4.17 90.74 100 0.150 -  300 +  150 300 1.04 10.58 86.57 170 0.090 -  150 +  90 150 1.35 13.73 75.99  0.000 -90 90 6.12 62.26 62.26 Total 9.83 100.00     88  1/2"St-10MagB120 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 14 1.400 -1680 + 1400 1680 0.00 0.00 100.00 16 1.200 -1400 + 1200 1400 1.62 16.58 100.00 18 1.000 -1200 + 1000 1200 1.03 10.54 83.42 20 0.850 -1000 +  850 1000 0.99 10.13 72.88 30 0.589 -  710 +  589 850 1.03 10.54 62.74 35 0.500  - 589 +  500 589 0.60 6.14 52.20 50 0.300 -  500 +  300 500 1.38 14.12 46.06 70 0.210 -  300 +  210 300 0.97 9.93 31.93 100 0.150 -  210 +  150 210 0.72 7.37 22.01 140 0.105 -  150 +  105 150 0.64 6.55 14.64 200 0.075 -  105 +  75 105 0.34 3.48 8.09 270 0..053 -  53 +  37 75 0.21 2.15 4.61 400 0..37 -  75 +  54 53 0.15 1.54 2.46 -37 37 0.09 0.92 0.92 Total 9.77 100.00  1/2"St-10MagB135 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 14 1.400 -1680 + 1400 1680 0.00 0.00 100.00 16 1.200 -1400 + 1200 1400 1.22 12.55 100.00 18 1.000 -1200 + 1000 1200 0.83 8.54 87.45 20 0.850 -1000 +  850 1000 0.65 6.69 78.91 30 0.589 -  710 +  589 850 0.89 9.16 72.22 35 0.500  - 589 +  500 589 0.47 4.84 63.07 50 0.300 -  500 +  300 500 1.24 12.76 58.23 70 0.210 -  300 +  210 300 0.95 9.77 45.47 100 0.150 -  210 +  150 210 0.81 8.33 35.70 140 0.105 -  150 +  105 150 0.83 8.54 27.37 200 0.075 -  105 +  75 105 0.60 6.17 18.83 270 0..053 -  53 +  37 75 0.53 5.45 12.65 400 0..37 -  75 +  54 53 0.39 4.01 7.20 -37 37 0.31 3.19 3.19 Total 9.72 100.00  89  1/2"St-10MagB186 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 14 1.400 -1680 + 1400 1680 0.00 0.00 100.00 16 1.200 -1400 + 1200 1400 0.48 4.92 100.00 18 1.000 -1200 + 1000 1200 0.39 4.00 95.08 20 0.850 -1000 +  850 1000 0.50 5.13 91.08 30 0.589 -  710 +  589 850 0.91 9.33 85.95 35 0.500  - 589 +  500 589 0.44 4.51 76.62 50 0.300 -  500 +  300 500 1.14 11.69 72.10 70 0.210 -  300 +  210 300 0.91 9.33 60.41 100 0.150 -  210 +  150 210 0.81 8.31 51.08 140 0.105 -  150 +  105 150 0.68 6.97 42.77 200 0.075 -  105 +  75 105 0.66 6.77 35.79 270 0..053 -  53 +  37 75 0.62 6.36 29.03 400 0..37 -  75 +  54 53 0.65 6.67 22.67 -37 37 1.56 16.00 16.00 Total 9.75 100.00  1/2"St-10MagB222 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 14 1.400 -1680 + 1400 1680 0.00 0.00 100.00 16 1.200 -1400 + 1200 1400 0.30 3.04 100.00 18 1.000 -1200 + 1000 1200 0.20 2.02 96.96 20 0.850 -1000 +  850 1000 0.34 3.44 94.94 30 0.589 -  710 +  589 850 0.69 6.98 91.50 35 0.500  - 589 +  500 589 0.32 3.24 84.51 50 0.300 -  500 +  300 500 1.07 10.83 81.28 70 0.210 -  300 +  210 300 0.87 8.81 70.45 100 0.150 -  210 +  150 210 0.77 7.79 61.64 140 0.105 -  150 +  105 150 0.65 6.58 53.85 200 0.075 -  105 +  75 105 0.61 6.17 47.27 270 0..053 -  53 +  37 75 0.60 6.07 41.09 400 0..37 -  75 +  54 53 0.63 6.38 35.02 -37 37 2.83 28.64 28.64 Total 9.88 100.00   90  1/2"St-10MagB307 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 14 1.400 -1680 + 1400 1680 0.00 0.00 100.00 16 1.200 -1400 + 1200 1400 0.35 3.55 100.00 18 1.000 -1200 + 1000 1200 0.17 1.72 96.45 20 0.850 -1000 +  850 1000 0.20 2.03 94.73 30 0.589 -  710 +  589 850 0.42 4.26 92.71 35 0.500  - 589 +  500 589 0.22 2.23 88.45 50 0.300 -  500 +  300 500 0.52 5.27 86.22 70 0.210 -  300 +  210 300 0.50 5.07 80.95 100 0.150 -  210 +  150 210 0.44 4.46 75.89 140 0.105 -  150 +  105 150 0.57 5.78 71.43 200 0.075 -  105 +  75 105 0.59 5.98 65.65 270 0..053 -  53 +  37 75 0.63 6.38 59.68 400 0..37 -  75 +  54 53 0.73 7.40 53.29 -37 37 4.53 45.90 45.90 Total 9.87 100.00  1/2"St-10MagC107 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 12 1.680 -2000 + 1680 2000 0.00 0.00 100.00 14 1.400 -1680 + 1400 1680 2.00 20.73 100.00 16 1.200 -1400 + 1200 1400 1.40 14.51 79.27 18 1.000 -1200 + 1000 1200 0.70 7.25 64.77 20 0.850 -1000 +  850 1000 0.70 7.25 57.51 25 0.710 -  850 +  710 850 0.80 8.29 50.26 30 0.589 -  710 +  589 710 0.50 5.18 41.97 35 0.500  - 589 +  500 589 0.35 3.63 36.79 40 0.425 -  500 +  425 500 0.20 2.07 33.16 50 0.300 -  425 +  300 425 0.65 6.74 31.09 100 0.150 -  300 +  150 300 1.20 12.44 24.35  0.000 -150 150 1.15 11.92 11.92 Total 9.65 100.00   91  1/2"St-10MagC127 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 12 1.680 -2000 + 1680 2000 0 0.00 100.00 14 1.400 -1680 + 1400 1680 0.97 10.74 100.00 16 1.200 -1400 + 1200 1400 1.13 12.51 89.26 18 1.000 -1200 + 1000 1200 0.67 7.42 76.74 20 0.850 -1000 +  850 1000 0.68 7.53 69.32 25 0.710 -  850 +  710 850 0.53 5.87 61.79 30 0.589 -  710 +  589 710 0.52 5.76 55.92 35 0.500  - 589 +  500 589 0.49 5.43 50.17 40 0.425 -  500 +  425 500 0.52 5.76 44.74 50 0.300 -  425 +  300 425 0.8 8.86 38.98 100 0.150 -  300 +  150 300 1.31 14.51 30.12  0.000 -150 150 1.41 15.61 15.61 Total 9.03 100.00   1/2"St-10MagC154 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 12 1.680 -2000 + 1680 2000 0 0.00 100.00 14 1.400 -1680 + 1400 1680 0.62 6.47 100.00 16 1.200 -1400 + 1200 1400 0.83 8.65 93.53 18 1.000 -1200 + 1000 1200 0.45 4.69 84.88 20 0.850 -1000 +  850 1000 0.6 6.26 80.19 25 0.710 -  850 +  710 850 0.53 5.53 73.93 30 0.589 -  710 +  589 710 0.51 5.32 68.40 35 0.500  - 589 +  500 589 0.51 5.32 63.09 40 0.425 -  500 +  425 500 0.53 5.53 57.77 50 0.300 -  425 +  300 425 0.93 9.70 52.24 100 0.150 -  300 +  150 300 1.46 15.22 42.54  0.000 -150 150 2.62 27.32 27.32 Total 9.59 100.00   92  1/2"St-10MagC268 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 12 1.680 -2000 + 1680 2000 0 0.00 100.00 14 1.400 -1680 + 1400 1680 0.12 1.22 100.00 16 1.200 -1400 + 1200 1400 0.22 2.24 98.78 18 1.000 -1200 + 1000 1200 0.11 1.12 96.53 20 0.850 -1000 +  850 1000 0.20 2.04 95.41 25 0.710 -  850 +  710 850 0.19 1.94 93.37 30 0.589 -  710 +  589 710 0.21 2.14 91.44 35 0.500  - 589 +  500 589 0.28 2.85 89.30 40 0.425 -  500 +  425 500 0.15 1.53 86.44 50 0.300 -  425 +  300 425 0.49 4.99 84.91 100 0.150 -  300 +  150 300 1.10 11.21 79.92  0.000 -150 150 6.74 68.71 68.71 Total 9.81 100.00   1/2"St-10MagC337 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 12 1.680 -2000 + 1680 2000 0 0.00 100.00 14 1.400 -1680 + 1400 1680 0.12 1.23 100.00 16 1.200 -1400 + 1200 1400 0.12 1.23 98.77 18 1.000 -1200 + 1000 1200 0.12 1.23 97.53 20 0.850 -1000 +  850 1000 0.12 1.23 96.30 25 0.710 -  850 +  710 850 0.08 0.82 95.06 30 0.589 -  710 +  589 710 0.16 1.65 94.24 35 0.500  - 589 +  500 589 0.20 2.06 92.60 40 0.425 -  500 +  425 500 0.22 2.26 90.54 50 0.300 -  425 +  300 425 0.41 4.11 88.28 100 0.150 -  300 +  150 300 0.81 8.23 84.17  0.000 -150 150 7.51 75.94 75.94 Total 9.89 100.00   93  1/2"St-10MagD118 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 -2362 + 2000 2362 0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 1.16 11.76 100.00 14 1.400 -1680 + 1400 1680 1.39 14.10 88.24 16 1.200 -1400 + 1200 1400 0.98 9.94 74.14 18 1.000 -1200 + 1000 1200 0.73 7.40 64.20 20 0.850 -1000 +  850 1000 0.83 8.42 56.80 25 0.710 -  850 +  710 850 0.91 9.23 48.38 30 0.589 -  710 +  589 710 0.64 6.49 39.15 35 0.500  - 589 +  500 589 0.76 7.71 32.66 40 0.425 -  500 +  425 500 0.63 6.39 24.95 50 0.300 -  425 +  300 425 0.81 8.22 18.56 100 0.150 -  300 +  150 300 0.60 6.09 10.34 170 0.090 -  150 +  90 150 0.16 1.62 4.26  0.000 -90 90 0.26 2.64 2.64 Total 9.86 100.00  1/2"St-10MagD142 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 -2362 + 2000 2362 0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.53 5.39 100.00 14 1.400 -1680 + 1400 1680 0.96 9.80 94.61 16 1.200 -1400 + 1200 1400 0.74 7.52 84.80 18 1.000 -1200 + 1000 1200 0.50 5.07 77.29 20 0.850 -1000 +  850 1000 0.80 8.17 72.22 25 0.710 -  850 +  710 850 0.82 8.33 64.05 30 0.589 -  710 +  589 710 0.77 7.84 55.72 35 0.500  - 589 +  500 589 0.75 7.68 47.88 40 0.425 -  500 +  425 500 0.56 5.72 40.20 50 0.300 -  425 +  300 425 1.12 11.44 34.48 100 0.150 -  300 +  150 300 1.37 14.05 23.04 170 0.090 -  150 +  90 150 0.37 3.76 8.99  0.000 -90 90 0.51 5.23 5.23 Total 9.78 100.00  94  1/2"St-10MagD193 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 -2362 + 2000 2362 0 0.00 100.00 12 1.680 -2000 + 1680 2000 0.21 2.19 100.00 14 1.400 -1680 + 1400 1680 0.43 4.48 97.81 16 1.200 -1400 + 1200 1400 0.34 3.55 93.33 18 1.000 -1200 + 1000 1200 0.27 2.82 89.78 20 0.850 -1000 +  850 1000 0.41 4.28 86.97 25 0.710 -  850 +  710 850 0.44 4.59 82.69 30 0.589 -  710 +  589 710 0.39 4.07 78.10 35 0.500  - 589 +  500 589 0.52 5.42 74.04 40 0.425 -  500 +  425 500 0.49 5.11 68.61 50 0.300 -  425 +  300 425 1.30 13.56 63.50 100 0.150 -  300 +  150 300 1.85 19.29 49.95 170 0.090 -  150 +  90 150 1.13 11.78 30.66  0.000 -90 90 1.81 18.87 18.87 Total 9.59 100.00  1/2"St-10MagD275 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 -2362 + 2000 2362 0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.03 0.30 100.00 14 1.400 -1680 + 1400 1680 0.09 0.92 99.70 16 1.200 -1400 + 1200 1400 0.08 0.81 98.79 18 1.000 -1200 + 1000 1200 0.12 1.22 97.98 20 0.850 -1000 +  850 1000 0.16 1.63 96.75 25 0.710 -  850 +  710 850 0.18 1.83 95.13 30 0.589 -  710 +  589 710 0.14 1.42 93.30 35 0.500  - 589 +  500 589 0.26 2.65 91.87 40 0.425 -  500 +  425 500 0.22 2.24 89.23 50 0.300 -  425 +  300 425 0.57 5.80 86.99 100 0.150 -  300 +  150 300 1.76 17.91 81.19 170 0.090 -  150 +  90 150 1.97 20.04 63.28  0.000 -90 90 4.25 43.24 43.24 Total 9.83 100.00 1/2"St-10MagD342 US Mesh Size  Size Range  Passing Weight (g) Weight Cumulative 95  (mm) (µm) Size (µm) (%) % Passing 10 2.000 -2362 + 2000 2362 0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.02 0.20 100.00 14 1.400 -1680 + 1400 1680 0.06 0.61 99.80 16 1.200 -1400 + 1200 1400 0.07 0.71 99.19 18 1.000 -1200 + 1000 1200 0.09 0.92 98.47 20 0.850 -1000 +  850 1000 0.13 1.32 97.56 25 0.710 -  850 +  710 850 0.14 1.42 96.23 30 0.589 -  710 +  589 710 0.14 1.42 94.81 35 0.500  - 589 +  500 589 0.15 1.53 93.39 40 0.425 -  500 +  425 500 0.18 1.83 91.86 50 0.300 -  425 +  300 425 0.47 4.78 90.03 100 0.150 -  300 +  150 300 1.19 12.08 85.24 170 0.090 -  150 +  90 150 0.95 9.67 73.17  0.000 -90 90 6.24 63.50 63.50 Total 9.83 100.00  1/2"St-10MagAD72 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 1.29 13.16 100.00 14 1.400 -1680 + 1400 1680 0.86 8.78 86.84 16 1.200 -1400 + 1200 1400 0.54 5.51 78.06 18 1.000 -1200 + 1000 1200 0.35 3.57 72.55 20 0.850 -1000 +  850 1000 0.33 3.37 68.98 30 0.589 -  710 +  589 850 0.71 7.24 65.61 35 0.500  - 589 +  500 589 0.50 5.10 58.37 40 0.425 -  500 +  425 500 1.15 11.73 53.27 50 0.300 -  425 +  300 425 1.61 16.43 41.53 100 0.150 -  300 +  150 300 1.59 16.22 25.10 140 0.105 -  150 +  105 150 0.53 5.41 8.88 200 0.075 -  105 +  75 105 0.23 2.35 3.47 270 0..053 -  53 +  37 75 0.07 0.71 1.12 400 0..37 -  75 +  54 53 0.02 0.20 0.41 -37 37 0.02 0.20 0.20 Total 9.80 100.00  96  1/2"St-10MagAD129 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.88 9.15 100.00 14 1.400 -1680 + 1400 1680 0.72 7.48 90.85 16 1.200 -1400 + 1200 1400 0.48 4.99 83.37 18 1.000 -1200 + 1000 1200 0.34 3.53 78.38 20 0.850 -1000 +  850 1000 0.44 4.57 74.84 30 0.589 -  710 +  589 850 0.72 7.48 70.27 35 0.500  - 589 +  500 589 0.64 6.65 62.79 40 0.425 -  500 +  425 500 0.98 10.19 56.13 50 0.300 -  425 +  300 425 1.41 14.66 45.95 100 0.150 -  300 +  150 300 1.45 15.07 31.29 140 0.105 -  150 +  105 150 0.66 6.86 16.22 200 0.075 -  105 +  75 105 0.55 5.72 9.36 270 0..053 -  53 +  37 75 0.25 2.60 3.64 400 0..37 -  75 +  54 53 0.07 0.73 1.04 -37 37 0.03 0.31 0.31 Total 9.62 100.00  1/2"St-10MagAD148 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.69 6.93 100.00 14 1.400 -1680 + 1400 1680 0.61 6.12 93.07 16 1.200 -1400 + 1200 1400 0.44 4.42 86.95 18 1.000 -1200 + 1000 1200 0.37 3.71 82.53 20 0.850 -1000 +  850 1000 0.51 5.12 78.82 30 0.589 -  710 +  589 850 0.75 7.53 73.69 35 0.500  - 589 +  500 589 0.72 7.23 66.16 40 0.425 -  500 +  425 500 0.95 9.54 58.94 50 0.300 -  425 +  300 425 1.38 13.86 49.40 100 0.150 -  300 +  150 300 1.54 15.46 35.54 140 0.105 -  150 +  105 150 0.83 8.33 20.08 200 0.075 -  105 +  75 105 0.62 6.22 11.75 270 0..053 -  53 +  37 75 0.36 3.61 5.52 400 0..37 -  75 +  54 53 0.13 1.31 1.91 -37 37 0.06 0.60 0.60 Total 9.96 100.00 97  1/2"St-10MagAD171 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.37 3.77 100.00 14 1.400 -1680 + 1400 1680 0.39 3.97 96.23 16 1.200 -1400 + 1200 1400 0.34 3.46 92.26 18 1.000 -1200 + 1000 1200 0.38 3.87 88.80 20 0.850 -1000 +  850 1000 0.58 5.91 84.93 30 0.589 -  850 +  589 850 0.71 7.23 79.02 35 0.500  - 589 +  500 589 0.76 7.74 71.79 40 0.425 -  500 +  425 500 0.79 8.04 64.05 50 0.300 -  425 +  300 425 1.20 12.22 56.01 100 0.150 -  300 +  150 300 1.53 15.58 43.79 140 0.105 -  150 +  105 150 0.77 7.84 28.21 200 0.075 -  105 +  75 105 0.83 8.45 20.37 270 0..053 -  53 +  37 75 0.72 7.33 11.91 400 0..37 -  75 +  54 53 0.31 3.16 4.58 -37 37 0.14 1.43 1.43 Total 9.82 100.00  1/2"St-10MagAD72 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.24 2.44 100.00 14 1.400 -1680 + 1400 1680 0.27 2.75 97.56 16 1.200 -1400 + 1200 1400 0.28 2.85 94.81 18 1.000 -1200 + 1000 1200 0.33 3.36 91.96 20 0.850 -1000 +  850 1000 0.43 4.37 88.61 30 0.589 -  850 +  589 850 0.59 6.00 84.23 35 0.500  - 589 +  500 589 0.63 6.41 78.23 40 0.425 -  500 +  425 500 0.66 6.71 71.82 50 0.300 -  425 +  300 425 1.01 10.27 65.11 100 0.150 -  300 +  150 300 1.51 15.36 54.83 140 0.105 -  150 +  105 150 0.98 9.97 39.47 200 0.075 -  105 +  75 105 0.91 9.26 29.50 270 0..053 -  53 +  37 75 0.77 7.83 20.24 400 0..37 -  75 +  54 53 0.53 5.39 12.41 -37 37 0.69 7.02 7.02 Total 9.83 100.00 98  1/2"St-10MagAD268 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.24 2.47 100.00 14 1.400 -1680 + 1400 1680 0.16 1.64 97.53 16 1.200 -1400 + 1200 1400 0.04 0.41 95.89 18 1.000 -1200 + 1000 1200 0.06 0.62 95.48 20 0.850 -1000 +  850 1000 0.10 1.03 94.86 30 0.589 -  710 +  589 850 0.26 2.67 93.83 35 0.500  - 589 +  500 589 0.07 0.72 91.16 40 0.425 -  500 +  425 500 0.40 4.11 90.44 50 0.300 -  425 +  300 425 0.69 7.09 86.33 100 0.150 -  300 +  150 300 1.15 11.82 79.24 140 0.105 -  150 +  105 150 0.66 6.78 67.42 200 0.075 -  105 +  75 105 0.46 4.73 60.64 270 0..053 -  53 +  37 75 0.40 4.11 55.91 400 0..37 -  75 +  54 53 0.63 6.47 51.80 -37 37 4.41 45.32 45.32 Total 9.73 100.00  1/2"St-10MagAD400 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.01 0.14 100.00 14 1.400 -1680 + 1400 1680 0.02 0.21 99.86 16 1.200 -1400 + 1200 1400 0.04 0.38 99.65 18 1.000 -1200 + 1000 1200 0.04 0.40 99.27 20 0.850 -1000 +  850 1000 0.09 0.92 98.87 30 0.589 -  710 +  589 850 0.19 1.90 97.96 35 0.500  - 589 +  500 589 0.18 1.83 96.05 40 0.425 -  500 +  425 500 0.27 2.73 94.23 50 0.300 -  425 +  300 425 0.43 4.39 91.49 100 0.150 -  300 +  150 300 0.85 8.63 87.11 140 0.105 -  150 +  105 150 0.53 5.39 78.47 200 0.075 -  105 +  75 105 0.46 4.72 73.08 270 0..053 -  53 +  37 75 0.62 6.29 68.36 400 0..37 -  75 +  54 53 0.85 8.70 62.07 -37 37 5.22 53.37 53.37 Total 9.79 100.00 99  1/4"St-10MagAD170 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.37 3.78 100.00 14 1.400 -1680 + 1400 1680 0.74 7.55 96.22 16 1.200 -1400 + 1200 1400 0.57 5.82 88.67 18 1.000 -1200 + 1000 1200 0.46 4.69 82.86 20 0.850 -1000 +  850 1000 0.79 8.06 78.16 30 0.589 -  710 +  589 850 1.40 14.29 70.10 35 0.500  - 589 +  500 589 0.46 4.69 55.82 50 0.300 -  500 +  300 500 1.26 12.86 51.12 70 0.210 -  300 +  210 300 0.65 6.63 38.27 100 0.150 -  210 +  150 210 0.66 6.73 31.63 140 0.105 -  150 +  105 150 0.53 5.41 24.90 200 0.075 -  105 +  75 105 0.49 5.00 19.49 270 0..053 -  53 +  37 75 0.35 3.57 14.49 400 0..37 -  75 +  54 53 0.28 2.86 10.92 -37 37 0.79 8.06 8.06 Total 9.80 100.00  1/4"St-10MagAD235 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 10 12 1.680 -2000 + 1680 2000 0.16 1.64 12 14 1.400 -1680 + 1400 1680 0.33 3.37 14 16 1.200 -1400 + 1200 1400 0.26 2.66 16 18 1.000 -1200 + 1000 1200 0.21 2.15 18 20 0.850 -1000 +  850 1000 0.40 4.09 20 30 0.589 -  710 +  589 850 0.71 7.26 30 35 0.500  - 589 +  500 589 0.25 2.56 35 50 0.300 -  500 +  300 500 0.78 7.98 50 70 0.210 -  300 +  210 300 0.49 5.01 70 100 0.150 -  210 +  150 210 0.48 4.91 100 140 0.105 -  150 +  105 150 0.52 5.32 140 200 0.075 -  105 +  75 105 0.64 6.54 200 270 0..053 -  53 +  37 75 0.82 8.38 270 400 0..37 -  75 +  54 53 1.18 12.07 400 -37 37 2.55 26.07 Total 9.78 100.00 100  1/4"St-10MagAD347 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.05 0.51 100.00 14 1.400 -1680 + 1400 1680 0.14 1.42 99.49 16 1.200 -1400 + 1200 1400 0.10 1.01 98.08 18 1.000 -1200 + 1000 1200 0.09 0.91 97.06 20 0.850 -1000 +  850 1000 0.22 2.23 96.15 30 0.589 -  710 +  589 850 0.37 3.74 93.93 35 0.500  - 589 +  500 589 0.14 1.42 90.18 50 0.300 -  500 +  300 500 0.58 5.87 88.77 70 0.210 -  300 +  210 300 0.46 4.66 82.89 100 0.150 -  210 +  150 210 0.38 3.85 78.24 140 0.105 -  150 +  105 150 0.43 4.35 74.39 200 0.075 -  105 +  75 105 0.51 5.16 70.04 270 0..053 -  53 +  37 75 0.61 6.17 64.88 400 0..37 -  75 +  54 53 1.21 12.25 58.70 -37 37 4.59 46.46 46.46 Total 9.88 100.00  1"St-10MagAD127 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.31 3.14 100.00 14 1.400 -1680 + 1400 1680 0.45 4.56 96.86 16 1.200 -1400 + 1200 1400 0.65 6.59 92.29 18 1.000 -1200 + 1000 1200 0.72 7.30 85.70 20 0.850 -1000 +  850 1000 0.88 8.92 78.40 30 0.589 -  710 +  589 850 1.32 13.39 69.47 35 0.500  - 589 +  500 589 0.68 6.90 56.09 50 0.300 -  500 +  300 500 1.36 13.79 49.19 70 0.210 -  300 +  210 300 0.73 7.40 35.40 100 0.150 -  210 +  150 210 0.68 6.90 27.99 140 0.105 -  150 +  105 150 0.60 6.09 21.10 200 0.075 -  105 +  75 105 0.49 4.97 15.01 270 0..053 -  53 +  37 75 0.39 3.96 10.04 400 0..37 -  75 +  54 53 0.32 3.25 6.09 -37 37 0.28 2.84 2.84 Total 9.86 100.00 101  1"St-10MagAD213 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.05 0.51 100.00 14 1.400 -1680 + 1400 1680 0.12 1.22 99.49 16 1.200 -1400 + 1200 1400 0.18 1.83 98.27 18 1.000 -1200 + 1000 1200 0.25 2.54 96.45 20 0.850 -1000 +  850 1000 0.34 3.45 93.91 30 0.589 -  710 +  589 850 0.75 7.61 90.46 35 0.500  - 589 +  500 589 0.20 2.03 82.84 50 0.300 -  500 +  300 500 1.36 13.81 80.81 70 0.210 -  300 +  210 300 1.08 10.96 67.01 100 0.150 -  210 +  150 210 1.15 11.68 56.04 140 0.105 -  150 +  105 150 1.06 10.76 44.37 200 0.075 -  105 +  75 105 1.03 10.46 33.60 270 0..053 -  53 +  37 75 0.87 8.83 23.15 400 0..37 -  75 +  54 53 0.73 7.41 14.31 -37 37 0.68 6.90 6.90 Total 9.85 100.00  1"St-10MagAD287 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.02 0.20 100.00 14 1.400 -1680 + 1400 1680 0.05 0.51 99.80 16 1.200 -1400 + 1200 1400 0.05 0.51 99.29 18 1.000 -1200 + 1000 1200 0.07 0.71 98.78 20 0.850 -1000 +  850 1000 0.11 1.12 98.06 30 0.589 -  710 +  589 850 0.40 4.08 96.94 35 0.500  - 589 +  500 589 0.16 1.63 92.86 50 0.300 -  500 +  300 500 0.88 8.97 91.23 70 0.210 -  300 +  210 300 0.74 7.54 82.26 100 0.150 -  210 +  150 210 1.12 11.42 74.72 140 0.105 -  150 +  105 150 1.15 11.72 63.30 200 0.075 -  105 +  75 105 1.08 11.01 51.58 270 0..053 -  53 +  37 75 1.01 10.30 40.57 400 0..37 -  75 +  54 53 1.15 11.72 30.28 -37 37 1.82 18.55 18.55 Total 9.81 100.00 102  1/2"Al-10MagAD146 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.84 8.57 100.00 14 1.400 -1680 + 1400 1680 1.29 13.16 91.43 16 1.200 -1400 + 1200 1400 0.90 9.18 78.27 18 1.000 -1200 + 1000 1200 0.53 5.41 69.08 20 0.850 -1000 +  850 1000 0.69 7.04 63.67 30 0.589 -  710 +  589 850 1.31 13.37 56.63 35 0.500  - 589 +  500 589 0.44 4.49 43.27 50 0.300 -  500 +  300 500 1.22 12.45 38.78 70 0.210 -  300 +  210 300 0.68 6.94 26.33 100 0.150 -  210 +  150 210 0.58 5.92 19.39 140 0.105 -  150 +  105 150 0.47 4.80 13.47 200 0.075 -  105 +  75 105 0.34 3.47 8.67 270 0..053 -  53 +  37 75 0.25 2.55 5.20 400 0..37 -  75 +  54 53 0.16 1.63 2.65 -37 37 0.10 1.02 1.02 Total 9.80 100.00  1/2"Al-10MagAD205 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.26 2.63 100.00 14 1.400 -1680 + 1400 1680 0.40 4.05 97.37 16 1.200 -1400 + 1200 1400 0.39 3.95 93.31 18 1.000 -1200 + 1000 1200 0.25 2.53 89.36 20 0.850 -1000 +  850 1000 0.42 4.26 86.83 30 0.589 -  710 +  589 850 1.00 10.13 82.57 35 0.500  - 589 +  500 589 0.61 6.18 72.44 50 0.300 -  500 +  300 500 1.12 11.35 66.26 70 0.210 -  300 +  210 300 0.85 8.61 54.91 100 0.150 -  210 +  150 210 0.81 8.21 46.30 140 0.105 -  150 +  105 150 0.70 7.09 38.10 200 0.075 -  105 +  75 105 0.68 6.89 31.00 270 0..053 -  53 +  37 75 0.62 6.28 24.11 400 0..37 -  75 +  54 53 0.58 5.88 17.83 -37 37 1.18 11.96 11.96 Total 9.87 100.00 103  1/2"Al -10MagAD272 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.12 1.26 100.00 14 1.400 -1680 + 1400 1680 0.18 1.89 98.74 16 1.200 -1400 + 1200 1400 0.22 2.31 96.86 18 1.000 -1200 + 1000 1200 0.14 1.47 94.55 20 0.850 -1000 +  850 1000 0.17 1.78 93.08 30 0.589 -  710 +  589 850 0.49 5.14 91.30 35 0.500  - 589 +  500 589 0.27 2.83 86.16 50 0.300 -  500 +  300 500 0.90 9.43 83.33 70 0.210 -  300 +  210 300 0.89 9.33 73.90 100 0.150 -  210 +  150 210 0.70 7.34 64.57 140 0.105 -  150 +  105 150 0.89 9.33 57.23 200 0.075 -  105 +  75 105 1.06 11.11 47.90 270 0..053 -  53 +  37 75 0.80 8.39 36.79 400 0..37 -  75 +  54 53 0.94 9.85 28.41 -37 37 1.77 18.55 18.55 Total 9.54 100.00  1/2"Al-10MagAD336 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.04 0.41 100.00 14 1.400 -1680 + 1400 1680 0.10 1.02 99.59 16 1.200 -1400 + 1200 1400 0.07 0.72 98.57 18 1.000 -1200 + 1000 1200 0.05 0.51 97.85 20 0.850 -1000 +  850 1000 0.15 1.54 97.34 30 0.589 -  710 +  589 850 0.47 4.81 95.80 35 0.500  - 589 +  500 589 0.22 2.25 90.99 50 0.300 -  500 +  300 500 0.61 6.24 88.74 70 0.210 -  300 +  210 300 0.45 4.61 82.50 100 0.150 -  210 +  150 210 0.65 6.65 77.89 140 0.105 -  150 +  105 150 0.88 9.01 71.24 200 0.075 -  105 +  75 105 0.91 9.31 62.23 270 0..053 -  53 +  37 75 0.84 8.60 52.92 400 0..37 -  75 +  54 53 1.13 11.57 44.32 -37 37 3.20 32.75 32.75 Total 9.77 100.00 104  1/2"Gl -10MagAD152 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 1.69 17.32 100.00 14 1.400 -1680 + 1400 1680 2.15 22.03 82.68 16 1.200 -1400 + 1200 1400 1.25 12.81 60.66 18 1.000 -1200 + 1000 1200 0.96 9.84 47.85 20 0.850 -1000 +  850 1000 0.95 9.73 38.01 30 0.589 -  710 +  589 850 1.14 11.68 28.28 35 0.500  - 589 +  500 589 0.36 3.69 16.60 50 0.300 -  500 +  300 500 0.61 6.25 12.91 70 0.210 -  300 +  210 300 0.26 2.66 6.66 100 0.150 -  210 +  150 210 0.14 1.43 4.00 140 0.105 -  150 +  105 150 0.09 0.92 2.56 200 0.075 -  105 +  75 105 0.07 0.72 1.64 270 0..053 -  53 +  37 75 0.04 0.41 0.92 400 0..37 -  75 +  54 53 0.03 0.31 0.51 -37 37 0.02 0.20 0.20 Total 9.76 100.00  1/2"Gl-10MagAD195 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.87 8.81 100.00 14 1.400 -1680 + 1400 1680 0.79 8.00 91.19 16 1.200 -1400 + 1200 1400 1.52 15.38 83.20 18 1.000 -1200 + 1000 1200 1.58 15.99 67.81 20 0.850 -1000 +  850 1000 1.18 11.94 51.82 30 0.589 -  710 +  589 850 1.43 14.47 39.88 35 0.500  - 589 +  500 589 0.52 5.26 25.40 50 0.300 -  500 +  300 500 0.84 8.50 20.14 70 0.210 -  300 +  210 300 0.43 4.35 11.64 100 0.150 -  210 +  150 210 0.25 2.53 7.29 140 0.105 -  150 +  105 150 0.15 1.52 4.76 200 0.075 -  105 +  75 105 0.10 1.01 3.24 270 0..053 -  53 +  37 75 0.08 0.81 2.23 400 0..37 -  75 +  54 53 0.05 0.51 1.42 -37 37 0.09 0.91 0.91 Total 9.88 100.00 105  1/2"Gl -10MagAD258 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.08 0.82 100.00 14 1.400 -1680 + 1400 1680 0.19 1.95 99.18 16 1.200 -1400 + 1200 1400 0.40 4.11 97.23 18 1.000 -1200 + 1000 1200 0.65 6.68 93.11 20 0.850 -1000 +  850 1000 0.68 6.99 86.43 30 0.589 -  710 +  589 850 1.15 11.82 79.45 35 0.500  - 589 +  500 589 0.73 7.50 67.63 50 0.300 -  500 +  300 500 1.67 17.16 60.12 70 0.210 -  300 +  210 300 0.90 9.25 42.96 100 0.150 -  210 +  150 210 0.78 8.02 33.71 140 0.105 -  150 +  105 150 0.70 7.19 25.69 200 0.075 -  105 +  75 105 0.55 5.65 18.50 270 0..053 -  53 +  37 75 0.46 4.73 12.85 400 0..37 -  75 +  54 53 0.33 3.39 8.12 -37 37 0.46 4.73 4.73 Total 9.73 100.00  1/2"Gl-10MagAD362 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.06 0.61 100.00 14 1.400 -1680 + 1400 1680 0.10 1.02 99.39 16 1.200 -1400 + 1200 1400 0.17 1.74 98.36 18 1.000 -1200 + 1000 1200 0.23 2.35 96.63 20 0.850 -1000 +  850 1000 0.34 3.48 94.27 30 0.589 -  710 +  589 850 0.55 5.62 90.80 35 0.500  - 589 +  500 589 0.20 2.04 85.17 50 0.300 -  500 +  300 500 0.77 7.87 83.13 70 0.210 -  300 +  210 300 0.62 6.34 75.26 100 0.150 -  210 +  150 210 0.66 6.75 68.92 140 0.105 -  150 +  105 150 0.62 6.34 62.17 200 0.075 -  105 +  75 105 0.72 7.36 55.83 270 0..053 -  53 +  37 75 0.85 8.69 48.47 400 0..37 -  75 +  54 53 1.12 11.45 39.78 -37 37 2.77 28.32 28.32 Total 9.78 100.00 106  GLProjectile152 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.12 3.86 100.00 12 1.680 -2000 + 1680 2000 0.15 4.82 96.14 14 1.400 -1680 + 1400 1680 0.24 7.72 91.32 16 1.200 -1400 + 1200 1400 0.17 5.47 83.60 18 1.000 -1200 + 1000 1200 0.11 3.54 78.14 20 0.850 -1000 +  850 1000 0.13 4.18 74.60 30 0.589 -  710 +  589 850 0.24 7.72 70.42 35 0.500  - 589 +  500 589 0.14 4.50 62.70 50 0.300 -  500 +  300 500 0.38 12.22 58.20 70 0.210 -  300 +  210 300 0.29 9.32 45.98 100 0.150 -  210 +  150 210 0.27 8.68 36.66 140 0.105 -  150 +  105 150 0.31 9.97 27.97 200 0.075 -  105 +  75 105 0.21 6.75 18.01 270 0..053 -  53 +  37 75 0.12 3.86 11.25 400 0..37 -  75 +  54 53 0.09 2.89 7.40 -37 37 0.14 4.50 4.50 Total 3.11 100.00  GLProjectile195 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.04 1.34 100.00 12 1.680 -2000 + 1680 2000 0.12 3.96 98.66 14 1.400 -1680 + 1400 1680 0.18 5.94 94.70 16 1.200 -1400 + 1200 1400 0.13 4.29 88.76 18 1.000 -1200 + 1000 1200 0.07 2.31 84.47 20 0.850 -1000 +  850 1000 0.12 3.96 82.16 30 0.589 -  710 +  589 850 0.18 5.94 78.20 35 0.500  - 589 +  500 589 0.07 2.31 72.26 50 0.300 -  500 +  300 500 0.35 11.55 69.95 70 0.210 -  300 +  210 300 0.26 8.58 58.41 100 0.150 -  210 +  150 210 0.28 9.24 49.83 140 0.105 -  150 +  105 150 0.26 8.58 40.59 200 0.075 -  105 +  75 105 0.22 7.26 32.01 270 0..053 -  53 +  37 75 0.17 5.61 24.75 400 0..37 -  75 +  54 53 0.12 3.96 19.14 -37 37 0.46 15.18 15.18 Total 3.03 100.00 107  GLProjectileAD258 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.03 0.95 100.00 12 1.680 -2000 + 1680 2000 0.04 1.26 99.05 14 1.400 -1680 + 1400 1680 0.06 1.89 97.79 16 1.200 -1400 + 1200 1400 0.06 1.89 95.90 18 1.000 -1200 + 1000 1200 0.05 1.58 94.01 20 0.850 -1000 +  850 1000 0.05 1.58 92.43 30 0.589 -  710 +  589 850 0.10 3.15 90.85 35 0.500  - 589 +  500 589 0.04 1.26 87.70 50 0.300 -  500 +  300 500 0.19 5.99 86.44 70 0.210 -  300 +  210 300 0.18 5.68 80.44 100 0.150 -  210 +  150 210 0.23 7.26 74.76 140 0.105 -  150 +  105 150 0.26 8.20 67.51 200 0.075 -  105 +  75 105 0.23 7.26 59.31 270 0..053 -  53 +  37 75 0.16 5.05 52.05 400 0..37 -  75 +  54 53 0.15 4.73 47.00 -37 37 1.34 42.27 42.27 Total 3.17 100.00  GLProjectile362 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.01 0.38 100.00 14 1.400 -1680 + 1400 1680 0.03 1.13 99.62 16 1.200 -1400 + 1200 1400 0.03 1.13 98.50 18 1.000 -1200 + 1000 1200 0.02 0.75 97.37 20 0.850 -1000 +  850 1000 0.02 0.75 96.62 30 0.589 -  710 +  589 850 0.06 2.26 95.86 35 0.500  - 589 +  500 589 0.03 1.13 93.61 50 0.300 -  500 +  300 500 0.11 4.14 92.48 70 0.210 -  300 +  210 300 0.11 4.14 88.35 100 0.150 -  210 +  150 210 0.14 5.26 84.21 140 0.105 -  150 +  105 150 0.14 5.26 78.95 200 0.075 -  105 +  75 105 0.13 4.89 73.68 270 0..053 -  53 +  37 75 0.14 5.26 68.80 400 0..37 -  75 +  54 53 0.07 2.63 63.53 -37 37 1.62 60.90 60.90 Total 2.66 100.00 108  1/2"St-5MagAD141 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.27 5.56 100.00 14 1.400 -1680 + 1400 1680 0.23 4.73 94.44 16 1.200 -1400 + 1200 1400 0.30 6.17 89.71 18 1.000 -1200 + 1000 1200 0.26 5.35 83.54 20 0.850 -1000 +  850 1000 0.27 5.56 78.19 30 0.589 -  710 +  589 850 0.51 10.49 72.63 35 0.500  - 589 +  500 589 0.20 4.12 62.14 50 0.300 -  500 +  300 500 0.50 10.29 58.02 70 0.210 -  300 +  210 300 0.36 7.41 47.74 100 0.150 -  210 +  150 210 0.35 7.20 40.33 140 0.105 -  150 +  105 150 0.36 7.41 33.13 200 0.075 -  105 +  75 105 0.31 6.38 25.72 270 0..053 -  53 +  37 75 0.32 6.58 19.34 400 0..37 -  75 +  54 53 0.27 5.56 12.76 -37 37 0.35 7.20 7.20 Total 4.86 100.00  1/2"St-5MagAD205 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.01 0.21 100.00 14 1.400 -1680 + 1400 1680 0.12 2.48 99.79 16 1.200 -1400 + 1200 1400 0.10 2.07 97.31 18 1.000 -1200 + 1000 1200 0.08 1.66 95.24 20 0.850 -1000 +  850 1000 0.16 3.31 93.58 30 0.589 -  710 +  589 850 0.41 8.49 90.27 35 0.500  - 589 +  500 589 0.15 3.11 81.78 50 0.300 -  500 +  300 500 0.65 13.46 78.67 70 0.210 -  300 +  210 300 0.44 9.11 65.22 100 0.150 -  210 +  150 210 0.48 9.94 56.11 140 0.105 -  150 +  105 150 0.46 9.52 46.17 200 0.075 -  105 +  75 105 0.53 10.97 36.65 270 0..053 -  53 +  37 75 0.42 8.70 25.67 400 0..37 -  75 +  54 53 0.37 7.66 16.98 -37 37 0.45 9.32 9.32 Total 4.83 100.00 109  1/2"St-5MagAD307 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.00 0.00 100.00 14 1.400 -1680 + 1400 1680 0.03 0.63 100.00 16 1.200 -1400 + 1200 1400 0.04 0.84 99.37 18 1.000 -1200 + 1000 1200 0.02 0.42 98.53 20 0.850 -1000 +  850 1000 0.08 1.68 98.11 30 0.589 -  710 +  589 850 0.25 5.25 96.43 35 0.500  - 589 +  500 589 0.08 1.68 91.18 50 0.300 -  500 +  300 500 0.41 8.61 89.50 70 0.210 -  300 +  210 300 0.28 5.88 80.88 100 0.150 -  210 +  150 210 0.37 7.77 75.00 140 0.105 -  150 +  105 150 0.42 8.82 67.23 200 0.075 -  105 +  75 105 0.51 10.71 58.40 270 0..053 -  53 +  37 75 0.59 12.39 47.69 400 0..37 -  75 +  54 53 0.67 14.08 35.29 -37 37 1.01 21.22 21.22 Total 4.76 100.00  1/2"St-15MagAD128 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 1.73 11.83 100.00 14 1.400 -1680 + 1400 1680 2.44 16.69 88.17 16 1.200 -1400 + 1200 1400 1.52 10.40 71.48 18 1.000 -1200 + 1000 1200 0.76 5.20 61.08 20 0.850 -1000 +  850 1000 0.91 6.22 55.88 30 0.589 -  710 +  589 850 1.83 12.52 49.66 35 0.500  - 589 +  500 589 0.65 4.45 37.14 50 0.300 -  500 +  300 500 1.79 12.24 32.69 70 0.210 -  300 +  210 300 0.93 6.36 20.45 100 0.150 -  210 +  150 210 0.84 5.75 14.09 140 0.105 -  150 +  105 150 0.59 4.04 8.34 200 0.075 -  105 +  75 105 0.31 2.12 4.31 270 0..053 -  53 +  37 75 0.18 1.23 2.19 400 0..37 -  75 +  54 53 0.10 0.68 0.96 -37 37 0.04 0.27 0.27 Total 14.62 100.00 110  1/2"St-15MagAD206 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.37 2.52 100.00 14 1.400 -1680 + 1400 1680 0.70 4.77 97.48 16 1.200 -1400 + 1200 1400 0.73 4.98 92.70 18 1.000 -1200 + 1000 1200 0.58 3.96 87.72 20 0.850 -1000 +  850 1000 0.99 6.75 83.77 30 0.589 -  710 +  589 850 1.92 13.10 77.01 35 0.500  - 589 +  500 589 0.58 3.96 63.92 50 0.300 -  500 +  300 500 1.88 12.82 59.96 70 0.210 -  300 +  210 300 1.21 8.25 47.14 100 0.150 -  210 +  150 210 1.27 8.66 38.88 140 0.105 -  150 +  105 150 1.18 8.05 30.22 200 0.075 -  105 +  75 105 1.06 7.23 22.17 270 0..053 -  53 +  37 75 0.87 5.93 14.94 400 0..37 -  75 +  54 53 0.60 4.09 9.00 -37 37 0.72 4.91 4.91 Total 14.66 100.00  1/2"St-15MagAD316 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 10 2.000 + 2000  0.00 0.00 100.00 12 1.680 -2000 + 1680 2000 0.07 0.48 100.00 14 1.400 -1680 + 1400 1680 0.15 1.03 99.52 16 1.200 -1400 + 1200 1400 0.19 1.30 98.49 18 1.000 -1200 + 1000 1200 0.14 0.96 97.19 20 0.850 -1000 +  850 1000 0.39 2.67 96.23 30 0.589 -  710 +  589 850 0.86 5.89 93.56 35 0.500  - 589 +  500 589 0.22 1.51 87.66 50 0.300 -  500 +  300 500 1.10 7.54 86.15 70 0.210 -  300 +  210 300 0.84 5.76 78.62 100 0.150 -  210 +  150 210 1.41 9.66 72.86 140 0.105 -  150 +  105 150 1.29 8.84 63.19 200 0.075 -  105 +  75 105 1.24 8.50 54.35 270 0..053 -  53 +  37 75 1.17 8.02 45.85 400 0..37 -  75 +  54 53 1.34 9.18 37.83 -37 37 4.18 28.65 28.65 Total 14.59 100.00 111   1/2"St-10MagE163 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 30 0.589 -  710 +  589 850 0.00 0.00 100.00 35 0.500  - 589 +  500 589 0.27 2.77 100.00 40 0.425 -  500 +  425 500 2.37 24.31 97.23 50 0.300 -  425 +  300 425 1.30 13.33 72.92 100 0.150 -  300 +  150 300 1.40 14.36 59.59 140 0.105 -  150 +  105 150 1.24 12.72 45.23 200 0.075 -  105 +  75 105 1.33 13.64 32.51 270 0..053 -  53 +  37 75 0.98 10.05 18.87 400 0..37 -  75 +  54 53 0.55 5.64 8.82 -37 37 0.31 3.18 3.18 Total 9.75 100.00  1/2"St-10MagE245 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 30 0.589 -  710 +  589 850 0.00 0.00 100.00 35 0.500  - 589 +  500 589 0.46 4.72 100.00 40 0.425 -  500 +  425 500 0.65 6.67 95.28 50 0.300 -  425 +  300 425 0.74 7.60 88.60 100 0.150 -  300 +  150 300 1.07 10.99 81.01 140 0.105 -  150 +  105 150 1.28 13.14 70.02 200 0.075 -  105 +  75 105 1.48 15.20 56.88 270 0..053 -  53 +  37 75 1.66 17.04 41.68 400 0..37 -  75 +  54 53 1.27 13.04 24.64 -37 37 1.13 11.60 11.60 Total 9.74 100.00     112   1/2"St-10MagE336 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 30 0.589 -  710 +  589 850 0.00 0.00 100.00 35 0.500  - 589 +  500 589 0.19 1.95 100.00 40 0.425 -  500 +  425 500 0.41 4.20 98.05 50 0.300 -  425 +  300 425 0.48 4.92 93.85 100 0.150 -  300 +  150 300 1.02 10.45 88.93 140 0.105 -  150 +  105 150 1.34 13.73 78.48 200 0.075 -  105 +  75 105 1.64 16.80 64.75 270 0..053 -  53 +  37 75 1.56 15.98 47.95 400 0..37 -  75 +  54 53 1.59 16.29 31.97 -37 37 1.53 15.68 15.68 Total 9.76 100.00  1/2"St-10MagF171 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 50 0.300 -  425 +  300 425 0.00 0.00 100.00 70 0.210 -  300 +  210 300 3.29 33.78 100.00 100 0.150 -  210 +  150 210 2.30 23.61 66.22 140 0.105 -  150 +  105 150 1.64 16.84 42.61 200 0.075 -  105 +  75 105 1.41 14.48 25.77 270 0..053 -  53 +  37 75 0.54 5.54 11.29 400 0..37 -  75 +  54 53 0.21 2.16 5.75 -37 37 0.35 3.59 3.59 Total 9.74 100.00      113   1/2"St-10MagF224 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 50 0.300 -  425 +  300 425 0.00 0.00 100.00 70 0.210 -  300 +  210 300 1.44 14.68 100.00 100 0.150 -  210 +  150 210 1.56 15.90 85.32 140 0.105 -  150 +  105 150 1.59 16.21 69.42 200 0.075 -  105 +  75 105 1.37 13.97 53.21 270 0..053 -  53 +  37 75 1.33 13.56 39.25 400 0..37 -  75 +  54 53 1.27 12.95 25.69 -37 37 1.25 12.74 12.74 Total 9.81 100.00  1/2"St-10MagF319 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 50 0.300 -  425 +  300 425 0.00 0.00 100.00 70 0.210 -  300 +  210 300 0.83 8.38 100.00 100 0.150 -  210 +  150 210 0.94 9.49 91.62 140 0.105 -  150 +  105 150 1.15 11.62 82.12 200 0.075 -  105 +  75 105 1.29 13.03 70.51 270 0..053 -  53 +  37 75 1.60 16.16 57.47 400 0..37 -  75 +  54 53 1.83 18.48 41.31 -37 37 2.26 22.83 22.83 Total 9.90 100.00       114  1/2"St-10MagG176 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 100 0.150 -  210 +  150 210 0.00 0.00 100.00 140 0.105 -  150 +  105 150 3.81 38.53 100.00 200 0.075 -  105 +  75 105 2.86 28.87 61.47 270 0..053 -  53 +  37 75 1.09 11.07 32.60 400 0..37 -  75 +  54 53 0.60 6.04 21.53 -37 37 1.53 15.49 15.49 Total 9.89 100.00  1/2"St-10MagG236 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 100 0.150 -  210 +  150 210 0.00 0.00 100.00 140 0.105 -  150 +  105 150 1.97 20.35 100.00 200 0.075 -  105 +  75 105 1.77 18.29 79.65 270 0..053 -  53 +  37 75 1.40 14.46 61.36 400 0..37 -  75 +  54 53 1.87 19.32 46.90 -37 37 2.67 27.58 27.58 Total 9.68 100.00  1/2"St-10MagG334 US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 100 0.150 -  210 +  150 210 0.00 0.00 100.00 140 0.105 -  150 +  105 150 1.06 10.69 100.00 200 0.075 -  105 +  75 105 1.11 11.19 89.31 270 0..053 -  53 +  37 75 1.88 18.95 78.13 400 0..37 -  75 +  54 53 2.56 25.81 59.17 -37 37 3.31 33.37 33.37 Total 9.92 100.00  115  APPENDIX C: BOND WORK INDEX DETERMINATION (MAGNETITE) Test Conditions Period Weight (gram)  Weight (gram)    Fresh Feed Undersize fresh feed # of revolutions Oversize Undersize Net Undersize Net Undersize Per Rev Circulating Load (%) 1 1985.1 279.42 200 1310.2 674.9 395.48 1.98 194.13 2 674.9 95.00 238.8 1387.5 597.6 502.60 2.10 232.18 3 597.6 84.12 229.5 1399.2 585.9 501.78 2.19 238.81 4 585.9 82.47 221.7 1408.6 576.5 494.03 2.23 244.34 5 576.5 81.15 218.1 1415.6 569.5 488.35 2.24 248.57 6 569.5 80.16 217.5 1416.2 568.9 488.74 2.25 248.94  Test Results Material Charge Weight - 700 ml (g) 1985.1 Test Sieve (µm) 150 IPP (g) 567.2 Undersize in feed (%) 14.08 Circulating Load (%) 249 Grindability (average) 2.24 Product P80 (µm) 134 Feed F80 (µm) 2055 BWI (kWh/t) 11.3 116   Feed Sieve Analysis US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 6 3.35 + 3350  0 0.00 100.00 8 2.38 -3350 + 2380 3350 143.96 9.26 100.00 10 2.000 -2380 + 2000 2380 195.55 12.58 90.74 12 1.680 -2000 + 1680 2000 176.02 11.32 78.16 14 1.400 -1680 + 1400 1680 165.20 10.62 66.84 16 1.200 -1400 + 1200 1400 107.36 6.90 56.22 18 1.000 -1200 + 1000 1200 90.76 5.84 49.31 20 0.850 -1000 +  850 1000 92.90 5.97 43.48 30 0.589 -  710 +  589 850 154.08 9.91 37.50 35 0.500  - 589 +  500 589 47.58 3.06 27.59 50 0.300 -  500 +  300 500 101.36 6.52 24.53 70 0.210 -  300 +  210 300 61.22 3.94 18.01 100 0.150 -  210 +  150 210 48.10 3.09 14.08 140 0.105 -  150 +  105 150 43.06 2.77 10.98 200 0.075 -  105 +  75 105 39.27 2.53 8.21 270 0..053 -  53 +  37 75 30.11 1.94 5.69 400 0..37 -  75 +  54 53 23.51 1.51 3.75   -37 37 34.81 2.24 2.24        Total 1554.85 100.00  117  Product Sieve Analysis US Mesh Size  (mm) Size Range  (µm) Passing Size (µm) Weight (g) Weight (%) Cumulative % Passing 70 0.210 -  300 +  210 300 0.0 0.00 100.00 100 0.150 -  210 +  150 210 0.0 0.00 100.00 140 0.105 -  150 +  105 150 291.3 51.20 100.00 200 0.075 -  105 +  75 105 154.1 27.09 48.80 270 0..053 -  53 +  37 75 71.1 12.50 21.71 400 0..37 -  75 +  54 53 35.7 6.28 9.21 -37 37 16.7 2.94 2.94        Total 568.90 100.00    Figure 53. Size analysis of the original feed  1 10 100 10 100 1000 10000 W e i g h t  %  C u m u l a t i v e  P a s s i n g Size (µm) P80 = 2055 µm 118   Figure 54. Size analysis of the final product  1 10 100 25 250 W e i g h t  %  C u m u l a t i v e  P a s s i n g ) Size (µm) P80 = 134 µm 119 120  APPENDIX D: CALCULATIONS OF THE MODIFIED BARMAC CRUSHER The power requirements of a crusher with a cylindrical rotor of a given height (h) and diameter (D), which accelerates rock particles to a certain tip speed (V) at the moment the particles leave the rotor, is given as follows: Power = G252G258Gd4cG3GcG23dG258Gd4cG3 G72fG726 Gb36G37a G7f1Gb37 Gd4c G72fG726 Gb36 G37a G1246G37aG738 Gb37 G726 Gb37 G1247 Gd4c G72fG738 Gb37 G726  G3G3G3G3G3G3G3G3G3G3G3G3Gd4c G3 G24eG376 G24fGb70G8aG7Gb36 G19 Gb37 G7 Gd4c G24eG376 G24fGb70G8aG7G19 Gb37 G59c Power = G24eG376 G24fGb70G8aG7G19 Gb37 The total production of such a crusher is given by as follows: Production = G17G88 Gd4c G3 G123aG373 Gd46 G88Gb74 G123bG13Gb70GfGb6eG88 Gd4c G3 G123aG373 Gd46 G88Gb74 G123bG88 G86Gb6eωG19Gb6e G123a G8aG95Gb6e G123b where, G86Gb6e Gd4c πGb48Gb71Gc66 G90G3, and G7f1 Gd4c GbcfGc17Gbbd, and G19Gb6e Gd4c G376 G375Gd57 πG123aGbe6GcdbGb36 G123bGb37 G59c Production = G123aGb35Gb3fGb64Gc6c G123bGb3aGb64 πG90G95Gb6eG8aG19 (m3/s)  or converting the units to tph: Production = 600G24e G373 Gd46 G88Gb74G88 ρG90G95Gb6eG8aG19 G8a Gd4c Rotor height (m) G7 Gd4c Rotor diameter (m) G19 Gd4c Rotor speed (m) G10 Gd4c Rotor mass (Kg) G24fGb70 = Rotor density (G96G1e4G8fG1e6G375) G90 Gd4c Number of G86G8bG95G85G8aG83G94G89G87G3G95G8eG91G96G95G3 G88Gb74 Gd4c Void fraction  G88 Gd4c Fraction of ore through rotor T = Rotor throughputG3(G8fG375G1e4G95G1e6G373) G3G24f = ore density (G96G1e4G8fG1e6G375) G95Gb6e Gd4c Particle size (m) G19Gb6e = Particle volume (G8fGb37) GfGb6e Gd4c Layers of particles G13Gb70 = Production rate (G8fG375G1e4G95G1e6G373) G86Gb6e = Particle dischargeG3G94G83G96G87  121  APPENDIX E: RECOMMENDED MODIFICATION OF TARGET CHAMBER Redesigning the target chamber to allow the volume of the void space in the sample to not contually decrease in volume as the sample is compressed during impact could result in sustaining the effects of high input energy on the efficiency of particle breakage and may eliminate the observed peak efficiency. One way to achieve would be to place the sample into a chamber consisting of an annulus around a central movable cylinder. Figure 56 provides the schematics for this chamber. In this apparatus, the projectile (having a tapered front-end) would enter the central cylinder and force particles out against the outer surface of the target chamber generating torsion forces in the particles as they move between the projectile and the chamber wall. This should enhance breakage due to higher transfer of energy as a shear force.  In this scenario, the resultant impact velocity on particles might be significantly less than the projectile velocity, but the distance that the particles move is also less. In addition, a component of the impact force creates shear stresses rather than normal compressive stresses which could also improve efficiency.                                          re 55. Schematics of a modified target chamber      Target Sample (Annular Ring) Void Space (Annular Ring) Movable "plastic" cylinder to support annular ring sample. This is pushed by the projectile past the sample target the annular ring sample above Projectile  Muzzle Figu Stationary steel ring to support 122 123  APPENDIX F: SAMPLE ASSAYING RESULTS  METHOD Fe-VOL51 ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a SAMPLE Fe Ag Al As Ba Be Bi DESCRIPTION % ppm % ppm ppm ppm ppm AMOUNT 67.94 <1 0.15 50 <50 <10 <20  METHODS ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a SAMPLE Ca Cd Co Cr Cu Fe Ga DESCRIPTION % ppm ppm ppm ppm % ppm AMOUNT 0.56 <10 110 50 30 >50 <50  METHODS ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a SAMPLE K La Mg Mn Mo Na Ni DESCRIPTION % ppm % ppm ppm % ppm AMOUNT <0.1 50 0.43 590 <10 0.13 410  METHODS ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a SAMPLE P Pb S Sb Sc Sr Th DESCRIPTION ppm ppm % ppm ppm ppm ppm AMOUNT 1720 690 0.13 <50 <10 10 <50  METHODS ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a ME-ICP61a Fe-VOL05 SAMPLE Ti Tl U V W Zn FeO DESCRIPTION % ppm ppm ppm ppm ppm % AMOUNT <0.05 <50 <50 1170 <50 1200 23.7  

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