MODELING AND SIMULATION OF MINERAL PROCESSING CIRCUITS USING JKSIMMET AND JKSIMFLOAT

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1 Preprnt MODELING AND SIMULATION OF MINERAL PROCESSING CIRCUITS USING JKSIMMET AND JKSIMFLOAT S. Schwarz, JKTech Pty Ltd, Indoorooplly, QLD Australa J. M. Rchardson, Contract Support Servces, Red Bluff, CA ABSTRACT In recent years there have been sgnfcant advances n computng power and programmng technology, enablng more complcated processes to be modelled n greater detal. Ths has led to ncreased understandng of these complex processes, ncludng mneral processng crcuts. JKSmMet was developed over the past 35 years, ncorporatng outcomes from varous research projects conducted at the Julus Kruttschntt Mneral Research Centre (JKMRC), part of the Sustanable Mnerals Insttute at The Unversty of Queensland. It s a steady-state software program that allows the user to mass balance, model ft and smulate crushng, grndng and classfcaton crcuts. JKSmFloat has been developed over the past 20 years, ncorporatng outcomes from the JKMRC and other nsttutons around the world through the AMIRA Internatonal P9 project The Optmsaton and Smulaton of Mneral Processng Crcuts. It s also a steady-state software program, smlar to JKSmMet, but s focused on analysng flotaton crcuts. Both programs have been used n a wde varety of optmsaton and desgn projects over many years. Ths paper provdes an overvew of both JKSmMet and JKSmFloat and examples of how both programs have been used to better understand, develop and optmse mneral processng crcuts around the world. INTRODUCTION The JK approach to smulatng crcuts has always been to decouple machne characterstcs from ore characterstcs and has spawned many very successful computer smulaton software packages; most notably JKSmMet (McKee & Naper-Munn 1990) and JKSmFloat (Schwarz and Alexander 2006b; Schwarz and Alexander 2007). Machne characterstcs are easly measureable and readly avalable n the database of parameters on record wth JKTech (Schwarz and Alexander 2006a). Ore characterstcs need to be determned for ndvdual ore bodes and breakage tests have been avalable some tme, from the batch wse orgnal Bond Work Index tests to the new mult-partcle test (Sh et al 2008). Tests for partcle floatablty have also recently been developed wth the JK Floatablty Index enablng predcton of plant performance based on laboratory flotaton results (Collns et al, 2009). Background to JKSmMet development The germnaton of many of the commnuton and classfcaton models found n JKSmMet today began wth the frst ncarnaton of the AMIRA P9 project n 1962, followed by the 1970 foundng and evoluton of the Julus Kruttschntt Mneral Research Centre (JKMRC). Ball mll, crusher and rod mll models appeared n the 1970 s based on work by Whten (Whten 1972) and Lynch (Lynch 1977) followed n the 1980 s wth hydrocyclone models based on the work of Lynch and Rao (Lynch and Rao 1975) and Nageswararao (Nageswararao 1978).Autogenous mll models were based on the work of Leung (1987) and partcle breakage modellng and measurement technques were developed by Narayanan and Whten (Narayanan and Whten 1983 and Narayanan 1985). Further commnuton studes, led by Morrell (Morrell and Morrson 1989, Morrell 1992, Morrell 1993,Morrell 1996) led to development of the varable rates Autogenous mll model and the power predcton methods found n JKSmMet. A model for hgh pressure grndng rolls (HPGR) based on work by Danel and Morrell (Danel 2002; Danel and Morrell 2004) was ntroduced n the early 2000 s. From the 1970 s through today, sophstcated numercal technques have been adapted and further refned for use n JKSmMet to perform functons of smulaton convergence, model fttng (calbraton) and mass balancng. (data reconclaton). By the early 1980 s models developed by the JKMRC had been collected and ntegrated nto a sngle smulator framework that was the forerunner of JKSmMet. The frst commercal verson of JKSmMet was ntroduced n 1986, concdng wth the foundng of JKTech, commercal arm of the JKMRC. One of the mneral ndustry s frst smulators to have a graphcal user nterface, the current verson of JKSmMet shares ts 3 rd - generaton nterface wth JKSmFloat, as well as ts 2 nd -generatonmultdmensonal mass balancng routne. Background to JKSmFloat development JKSmFloat ncorporates the modellng methodology developed as part of the AMIRA Internatonal P9 project, ttled The Optmsaton of Mneral Processes by Modellng and Smulaton and sponsored by many of the worlds leadng mneral processng companes and supplers to the ndustry. Ths s a collaboratve research project nvolvng the Julus Kruttschntt Mneral Research Centre (JKMRC) n Australa (from 1952), the Unversty of Cape Town (UCT) n South Afrca (from 1997),the McGll Unversty of Canada (from 2001), and other unverstes n more recent years. Ths methodology uses data obtaned from the flotaton plant and ncorporates varous sememprcal sub-process models to represent the data for smulatons. JKSIMMET Bass of models The JKSmMet commnuton models dvde commnuton performance nto that resultng from machne parameters, such as breakage rates (also known as selecton functons) from ore parameters, such as appearance functons (whch derve from measurement of an ore s resstance to breakage). The JKSmMet mll models belong to a generc famly of models known as populaton balance models, and they all share a common underlyng model whch nvolves solvng a steady-state balance around each ndvdual partcle sze found n the mll feed, load and product streams, as shown n the followng equaton: where: f - r. s + a j=1 - d = 0 1 Copyrght 2013 by SME j r f - fracton of sze n mll feed r - rate of breakage from sze to smaller szes n load s - fracton of sze contaned n mll load a j - appearance functon vector element whch specfes quantty of each larger broken partcle j appearng n sze d - rate of dscharge of sze from mll due to transport j s j s

2 The rates n the populaton balance equaton represent the machne parameters and the appearance functon s an ore parameter. At the heart of the hydrocyclone and other classfer models such as screens and trommels, s the well-known concept of the effcency curve, whch defnes the classfcaton performance. The JKSmMet cyclone model bulds on ths concept by addng correlaton equatons whch relate the normalzed classfcaton performance, as well as the capacty of the cyclone to certan equpment dmensons such as cyclone dameter, vortex fnder, apex and cone angle. Key model parameters n the equatons can be determned by the calbraton process known as model-fttng, allowng the user to then scale the ftted hydrocyclone (or parts of the ftted hydrocyclone) up or down from the actual cyclone whch was measured. When the commnuton and classfcaton model parameters have been calbrated to actual plant performance, the models can then be used to predct the performance of the plant when changes are made to the equpment dmensons or certan operatng condtons. Predctons can also be made to determne the effect of changng ore parameters, allowng the user to see how the plant performance wll vary wth changes n the feed. Case study 1: Model and optmze SAG-only crcut An exstng large tonnage copper operaton was operatng wth a sngle 38 ft, 19.4 MW SAG mll followed by two 25 ft 11.1 MW ball mlls. The SAG mll was operatng n a SAG-only confguraton, closed by a vbratng screen. A base-case model of the exstng crcut was constructed and model-ftted (calbrated) aganst plant survey data usng JKSmMet. The resultng model accurately depcted the grndng crcut condtons at the tme of the survey, as shown n the followng flowsheets: Fresh Feed Fresh Feed - Prod SAG H2O _MllLoad SAG Screen TPH - Solds (Sm) Volume Flow (Sm) - Prod SAG Screen - O/S Gross Power, kw Tot. Load, v/v% % Solds (Sm) P80 (Sm) Fgure 1. Case Study 1 Exstng SAG crcut flowsheet orgnal crcut as modelled wth JKSmMet. The crcut was surveyed durng a perod when the mll was beng fed by a typcal, recurrng hard ore type. Durng ths perod, prmary crusher product was typcally coarse, wth 80% passng sze (f80) = 119 mm. [Ore hardness parameters A, b and ta, are measured by the JKTech drop weght test. Ths partcular ore, whle nearly twce as hard compared to other ore types n the depost, was found to be soft when compared aganst several thousand measured ore types n the JKTech DWT data base.] Crcut throughput was 2,321 dmtph. The SAG mll and the ball mlls were all drawng sgnfcantly less power than nstalled motor capacty. Ths suggests all three mlls had suffcent power capacty for addtonal throughput. - Prod Prod BM 1 H2O BM 2 H2O - Prod U/F Prod U/F O/F Pressure, kpa Gross Power, kw O/F Pressure, kpa Gross Power, kw Fgure 2. Case Study 1 Ball mll crcut flowsheet orgnal crcut as modelled wth JKSmMet. The mll operators were nterested n determnng whether addng a pebble crusher to the SAG mll crcut would ncrease throughput and mll utlzaton. At the same tme, however, the goal was to mantan fnal grnd (cyclone overflow 80% passng sze or p80) as closes as possble to the baselne operaton wth p80 at 139 mcrons. JKSmMet demonstrated that sgnfcant extra throughput would result from nstallng a pebble crusher wth closed sde settng of 13 mm. At the same tme, SAG dscharge grates were ncreased from 38 mm to 63.5 mm to remove addtonal crtcal-szed materal from the SAG load; whle returnng materal wth p80 of 14.5 mm back to the SAG mll. As seen n the followng flowsheet, the effect of these changes was to ncrease SAG mll throughput by 16% to 2,692.5 dmtph. However, the addtonal throughput and coarser transfer sze (t80 = 3.66 mm vs 1.3 mm before addng the crusher), caused the ball mll crcut to produce a coarser product (p80 = 154 mcrons vs 139 mcrons before addng crusher). It was notced that the ball mlls were drawng well below nstalled power capacty at 9.36 MW or about 84% of nstalled capacty, wth ball charge at only 27%. Addtonally, the ball top sze was 76.2 mm, whch s too small for the mll, ore SG, work ndex and transfer sze, accordng to the Bond ball calculaton equaton: where: B = F K SgW (% C 3.281D s 3 B Ball dameter (mm) F F80 (mcrons) W Ball mll work ndex (kwh/mt) Sg Ore specfc gravty %CS Percent crtcal speed D Dameter nsde shell (m) K Constant = 350 for wet overflow mlls Copyrght 2013 by SME

3 Fresh Feed Fresh Feed - Prod SAG H2O Pebble Crusher CSS, mm Gross Power, kw Pebble Crusher Pebble Crusher - Prod Prod SAG Screen SAG Screen - O/S _MllLoad Gross Power, kw Tot. Load, v/v% Fgure 3. Case Study 1 SAG mll crcut wth pebble crusher added. It was also noted that an addtonal cyclone needed to be opened n each mll crcut, ncreasng from 9 to 10 operatng cyclones per ball mll, n order to keep cyclone / pump pressure below 60 kpa. The combnaton of smaller ball top sze (63.5 mm), and ncreasng the ball mll charge from 27 to 31.5 % v/v, and slght adjustment of percent solds n cyclone feed (lower water addton) had the desred effect of reducng fnal product p80 back to 139 mcrons, whle ncreasng ball mll power draw to about MW or 98% of nstalled capacty. At the same tme, crculatng load as a percent remaned at 207%, whle pump volume flow n each ball mll crcut ncreased from gpm to 16,438 gpm, stll wthn the maxmum capacty of the cyclone feed pumps. The solds overflow densty ncreased only slghtly from 45.7% to 46.5%. The followng fgure shows the effect of these changes on the ball mll crcut: The operatng company determned from ths exercse that the cost of nstallng the crusher was easly pad for by the ncreased throughput at dentcal recovery, snce t was also determned that there was suffcent extra capacty n the float crcut whch had been desgn to accept hgher throughput of softer ores. The pebble crusher was subsequently nstalled and surveys and modellng snce then has confrmed t s performng as predcted. Case study 2: Determne optmum mll / motor szes for an SABC grndng crcut n a pre-feasblty desgn study An operatng company wshed to develop an ore body, from whch a small number of drll core samples were avalable to establsh the prelmnary varablty of hardness wthn the depost. The samples were subjected to both JKTech drop weght testng to establsh SAG mll performance and Bond ball mll work ndex to establsh ball mll performance. From these tests, the 75 th percentle hardest ore among the samples wth respect to SAG performance per drop weght test A, b and t a parameters, was selected to provde the desgn bass values of these parameters, whle the 75 th percentle hardest sample wth respect to ball mll performance, provded the desgn bass value of Bond ball mll work ndex. These values, whle only slghtly softer than the mean of the large JKTech drop-tested sample database, are stll consdered to be soft yet competent. Ball mll work ndex at around 15 was consdered to be moderately hard. - Prod Prod BM 1 H2O BM 2 H2O - Prod U/F Prod U/F O/F Pressure, kpa Gross Power, kw O/F Pressure, kpa Gross Power, kw Fgure 4. Case Study 1 Ball mll crcut after pebble crusher added and ball mll optmzed by addng smaller balls and ncreasng ball charge. The only other desgn crtera provded were: Throughput = 50,000 92% avalablty = 2,264 dmtph nstantaneous Feed 80% passng sze (f80) = 150 mm Fnal Product 80% passng sze (p80) = 150 mcrons Crcut: 1 x SAG mll /pebble crusher/2 x ball mlls n SABC confguraton For ths desgn exercse, JKSmMet was used to buld a general model of the proposed SABC flowsheet. Once the model was constructed, dfferent typcal and realstc SAG mll dameter / length dmenson combnatons(avalable from mll vendors) were tested n successve smulatons to determne the mnmum sze mll whch meets the desgn throughput target at accepted operatng condtons whch allow operatonal flexblty as ore gets harder or softer than the 75 th percentle desgn bass sample: 12% SAG ball charge 78% crtcal speed (assume varable speed drve) 75% solds SAG feed/dscharge 25% total volumetrc load (rocks, balls and pulp) Slotted grate apertures wth wdth 50 to 63.5 mm In desgn studes where there s no plant to calbrate the model parameters, default values must be used. In ths case, the default breakage rate functon of the JKSmMet SAG model, whch was developed form over 60 sets of actual plant data wth a wde range of mll szes, s used. Wth the default breakage rate functon, a total load of 25% v/v, must be mantaned. If the load s exceeded at a gven set of desgn operatng condtons, ether the throughput or the mll sze must be decreased untl a 25% load s re-establshed. In ths manner, the optmum mll sze and ts related power draw s establshed. Once the mll sze and power draw to perform the actual work of the desgn crtera s known, t s assumed that the desgn bass ore would be drawng about 85% of nstalled motor capacty, allowng that nstalled capacty to be estmated. The followng fgure shows the SAG crcut for ths desgn project, whch resulted n determnng that a 36 x 19 ft SAG mll, wth 12% ball charge and operatng at crtcal speed, would meet the desgn crtera and would draw 12.7 MW n dong so. If 12.7 MW s assumed to be 85% of nstalled motor capacty, ths suggests a 15 MW motor. 3 Copyrght 2013 by SME

4 Fresh Feed TPH - Solds (Sm) Volume Flow (Sm) Stockple SAG H2O Stockple - Prod % Solds (Sm) P80 (Sm) Pebb Crusher - Prod Prod SAG Screen SAG Screen - O/S Fgure 5. Case Study 2 SABC crcut flowsheet pre-feasblty desgn study to sze SAG mll wth JKSmMet. Once the SAG mll sze and power has been determned, a Bond calculaton based on the desgn bass work ndex value s performed to determne the total power requred to reduce the SAG screen undersze product t80 to fnal target cyclone overflow p80 of 150 mcrons. Ths total power s found to be 20.3 MW at the pnon, and f a conservatve power loss of 5% across motor and drve s assumed, amounts to a gross power of 21.3 MW or MW per ball mll, f 2 mlls. Assumng ths gross power draw represents 98% of total motor capacty, nstalled motor power would be 10.9 MW per mll. JKSmMet ball mll model wth bult n power calculaton can be used to test dfferent reasonable (per mll vendor data) combnatons of dameter and length) needed to draw to 10.9 MW. In ths manner, two (2) x 24 x 36 ft ball mlls wth 10.9 MW motors are selected. The followng fgure shows the JKSmMet model of the ball mll crcut wth a sngle crcut representng total flows of 2 x ball mll crcuts. Cyclone parameters have been adjusted per best desgn practce to result n 250% crculatng load wth reasonable underflow densty (75% solds and about 40% solds overflow densty. JKSmMet predcts partcle sze dstrbuton, volumetrc flows, solds flows and pulp denstes for each stream and can thus be used by engneers to estmate pumps and ppng. The balance around the cyclones can be used by vendors to establsh best cyclone confguraton for ths duty. TPH - Solds (Sm) % Solds (Sm) Volume Flow (Sm) P80 (Sm) Cyc H2O x Ball Mls Gross Power, kw x Ball Mls - Prod BM 1 & 2 Cyclones 2 x Ball Mls BM 1 & 2 H2O BM 1 & 2 Cyclones - O/F BM 1 & 2 Cyclones - U/F Cyc Feed - Prod Fgure 6. Case Study 2 Ball mll crcut flowsheet pre-feasblty desgn study to sze SABC crcut ball mlls wth JKSmMet. Usng the results from ths study to obtan mll estmates from vendors, the operatng company has contnued on to a feasblty study, whch s currently underway. Addtonal drll samples wll be taken to confrm the hardness varablty and desgn bass and to brng the fnal mll szngs nto better focus. JKSIMFLOAT Bass of models As mentoned prevously, the models used wthn JKSmFloat dvde the flotaton performance nto that resultng from machne parameters, such as hydrodynamcs and froth performance, and ore parameters, such as susceptblty to flotaton. The underlyng model for predctng the recovery of a partcular group of partcles from flotaton cells (R ) n JKSmFloat s shown below: R where: = P Sb R f τ ( 1 Rw ) + ENT Rw ( 1 + P Sb R f τ )( 1 Rw ) + ENT Rw P ore floatablty for component, S b bubble surface area flux (mn -1 ) R f froth recovery τ- resdence tme (mn) R w water recovery (-) ENT degree of entranment (-) The methodology used to obtan the above parameters has been descrbed n detals elsewhere (Harrs et al, 1997; Alexander et al, 2000; Harrs et al, 2002). Case study 1: Kanowna Belle Gold Mne, Australa Kanowna Belle Gold Mne s located near Kalgoorle, n Western Australa wth the followng flowsheet: Plant Feed Flash Flotaton Rougher Column Rougher and Flash Concentrate Tank Cells Cleaners Wemco Scavengers Fgure 7. Kanowna Belle Gold Mne flotaton crcut flowsheet. 4 Copyrght 2013 by SME (1) Fnal tal Recleaners Fnal Concentrate A flotaton crcut model was developed based on surveys, cell measurements ncludng bubble sze, superfcal gas velocty, gas holdup, froth recovery, entranment, as well as laboratory batch flotaton tests and set up n JKSmFloat for use as a smulator (Alexander et al, 2005). Smulatons conducted ncluded: - Increasng water addton to the recleaners; - Recyclng the concentrate from the 2 nd stage of cleanng; - Further cleanng of the concentrate from the 1 st stage of mechancal cells; - Extra capacty n the recleaner bank. From these smulatons, t was dentfed that the hydrodynamcs n the cleaner and recleaner cells were lower than typcal and a further study ndcated the use of hgh shear stators would mprove the gas dsperson n these cells. The mplementaton of the ntal smulatons conducted for changng operatng condtons resulted n over 1.3% ncreased gold recovery n the flotaton crcut and an mprovement of US$1.3 mllon per year (Alexander et al, 2005). The mplementaton of the hgh shear stators mproved the gold flotaton recovery by 1.9% and had a project payback perod of 3 months (Blney et al, 2006). Case study 2: Century Znc Mne, Australa The Century lead-znc-slver depost s located approxmately 250km north-northwest of Mt Isa n north-western Queensland. A

5 schematc of the area of the process flowsheet nvestgated usng ths methodology s gven below: Grndng Crcut Feed Mll Feed Water Cone Crusher Roughers Screen Water Scavengers Vbratng Screen Cyclone Feed Water Ball Mll Cyclones Cyclone Feed Sump Flotaton Feed Cleaners Ball Mlls 3 n parallel Fgure 9. Laguna Seca grndng crcut flowsheet. Rougher Feed Rougher Crcut 6 rows of 9 cells Fgure 8. Century Znc flotaton crcut partal flowsheet. Note that only a porton of the flotaton crcut flowsheet s provded n Fgure as only ths porton was nvestgated usng the JKSmFloat methodology. A number of survey campagns were conducted around the Century prmary flotaton crcut from and models were developed from each campagn (Schwarz et al, 2008). Smulatons conducted ncluded: - Addton of a 200m 3 flotaton cell at the head of the scavenger crcut (mplemented n 2003); - Addtonal regrnd capacty; - Increased ar rates n scavenger and 1 st cleaner cells; - Increased feed rates; - Extra capacty n the rougher crcut. The combnaton of the model development and smulatons enabled Century personnel to sgnfcantly ncrease the throughput possble n the flotaton crcut whle mantanng the prmary znc crcut performance (Schwarz, 2009). GRINDING AND FLOTATION INTEGRATION A powerful applcaton of JKSmMet and JKSmFloat s by usng these programs together to predct the mpact of changng throughput and/or grnd sze on the flotaton crcut recovery. Case study 3: Mnera Escondda Lmtada, Chle Escondda s one of the largest copper producers n the world and s located n the Atacama Desert n northern Chle, 170km southeast of Antofagasta. An ntegrated grndng and flotaton study was conducted at Escondda usng both JKSmMet and JKSmFloat, based on the Laguna Seca concentrator (Coleman et al, 2007). A schematc of the flowsheets used s provded n Fgures 9 and 10. Models were developed of both the grndng and flotaton crcuts for use n JKSmMet and JKSmFloat. A number of smulatons were conducted, whch ncluded: - Change n flotaton feed sze dstrbuton; - Increase n grndng crcut capacty to ncrease throughput; - Estmaton of mpact of nstallng a flash flotaton crcut; - Flotaton crcut confguraton changes; - Increased flotaton crcut capacty. Escondda personnel performed laboratory and plant-scale trals for several of the smulaton scenaros and showed smlar trends to the ntegrated smulator results. Ths allowed decsons to be made regardng plant mprovements based on a valdated throughput-grnd sze-flotaton recovery relatonshp. Frst Cleaner Crcut 5 rows of 4 cells Regrnd Crcut 4 Vertcal Mlls Cleaner Scavenger Crcut 5 rows of 4 cells Second Cleaner Crcut 8 columns Rougher Tals Fnal Concentrate Fgure 10. Laguna Seca flotaton crcut flowsheet. Scavenger Tals Fnal T als Case study 4: Anglo Platnum, South Afrca Snce case study 3, a number of ntegrated studes have been conducted, wth the methodology beng expanded to nclude blast fragmentaton models. A major study was undertaken wth Anglo Platnum at one of ther operatng stes n South Afrca and combned the smulaton resources of JKSmBlast, JKSmMet and JKSmFloat (Zemsk et al, 2010). A geology-mne-plant ntegraton tool was developed to optmse performance as well as energy, water and greenhouse gas emssons. A schematc of the software archtecture s shown below: Fgure 11. An overvew of the geology-mne-plant ntegraton software archtecture. Usng ths tool, a number of optmsaton scenaros were conducted ncludng changes n ore hardness, ROM sze dstrbuton and operatng condtons. As well as the plant performance results, the energy consumpton and CO 2 producton was tracked to provde valuable sustanablty nformaton to ste personnel. As well as the plant optmsaton smulatons, a number of pt optmsaton smulatons were conducted to determne the mpact of dfferent ore types on the throughput and recovery n the plant. Ths 5 Copyrght 2013 by SME

6 nformaton was then fed back to the block model to redefne the zones of economc and uneconomc ores wthn the depost. CONCLUDING REMARKS In summary, software programs such as JKSmMet and JKSmFloat allow operators, metallurgsts, researchers and consultants a greater ablty to analyse, understand and optmse mneral processng crcuts. The JK methodology of separatng the ore and machne parameters has been proven many tmes over n ganng ths better understandng of the processes occurrng n commnuton and flotaton crcuts. Contnued research and mplementaton of ths methodology wll provde the ndustry wth very powerful tools to mprove mneral processng crcut performance. ACKNOWLEDGEMENTS The authors wsh to acknowledge the many JKMRC and JKTech staff and students assocated wth the development of the products dscussed n ths paper, together wth the ndustry companes who funded much of the development, often through AMIRA. REFERENCES Alexander, D.J. and Wgley, P Flotaton Crcut Analyss at WMC Ltd. Olympc Dam Operaton.In Proceedngs of the AusIMM 8th Mll Operators Conference, Townsvlle, Australa, August.The Australasan Insttute of Mnng and Metallurgy. Alexander, D.J., Blney, T., and Schwarz, S Flotaton Performance Improvement at Placer Dome Kanowna Belle Gold Mne.InProceedngs of the 37 th Annual Canadan Mll Operators Conference, Ottawa, Canada, January. Alexander, D.J., Runge, K.C., Franzds, J.P. and Manlapg, E.V The applcaton of mult-component floatablty models to full scale flotaton crcuts. In Proceedngs of theausimm7 th Mll Operators Conference, Kalgoorle, Australa, October Blney, T., McKnnon, S. and Kok, J. (2006); Assessment of hgh shear stator performance at Kanowna Belle Gold Mne, Proceedngs of MetPlant 2006, Perth. Coleman, R.G.,Urtuba, H.E., and Alexander, D.J A comparson of BHP-Bllton s MneraEscondda Flotaton Concentrators.In Proceedngs of the 38 th Annual Canadan Mll Operators Conference, Ottawa, Canada, January. 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Lynch, A.J. and Rao T.C Modelng and scale-up of hydrocyclone classfers.in Proceedngs XI Int Mn Proc Congress, Caglar, Paper 9. Lynch, A. J Mneral crushng and grndng crcuts; ther smulaton, optmzaton, desgn and control.elsever, 340 pp. McKee, D.J. and Naper-Munn, T.J The status of commnuton smulaton n Australa.Mnerals Engneerng, 3(1-2), Morrell, S. and Morrson, R.D Ore charge, ball load and materal flow effects on an energy based SAG mll model. In Proceedngs Advances n Autogenous and SAG Technology, Vancouver, Eds: Mular and Agar, (Unversty of Brtsh Columba). Morrell, S The smulaton of autogenous and sem-autogenous mllng crcuts.in Proceedngs Commnuton: Theory and Practce, Ed.: Kawatra, Ch 27, (AIME). Morrell, S The predcton of power draw n wet tumblng mlls. PhD. Thess Unversty of Queensland (JKMRC). Morrell, S. 1996a. Power draw of wet tumblng mlls and ts relatonshp to charge dynamcs Part 1: a contnuum approach to mathematcal modelng of mll power draw. Trans. 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InProceedngs of the Mneral Process Modellng, Smulaton and Control Conference, Laurentan Unversty, Sudbury, Schwarz, S. and Alexander, D Optmsaton of flotaton crcuts through smulaton usng JKSmFloat.In Proceedngs of the 33rd Internatonal Symposum on Applcaton of Computers and Operatons Research n the Mneral Industry (APCOM), Santago, Chle, Schwarz, S. and Klgarff, B Flotaton optmzaton studes of the Perlya Broken Hll lead crcut.in Proceedngs of the Centenary of Flotaton Symposum, Brsbane, Australa, The Australasan Insttute of Mnng and Metallurgy. Schwarz, S., Alexander, D., Whten, W.J., Franzds, J.P. and Harrs, M.C JKSmFloat V6: Improvng flotaton crcut performance and understandng. InProceedngs of the XXIII Internatonal Mneral Processng Congress, Istanbul, Turkey, September 2006, Schwarz, S., Crnkovc, I. and Alexander, D Flotaton crcut analyss at Znfex Century Mne.In Proceedngs of the 40 th Annual Canadan Mll Operators Conference, Ottawa, Canada, January. Schwarz, S., Obeng, D. and Alexander, D Improvng flotaton performance n the good, the bad and the ugly economc tmes the Century story.in Proceedngs of the AusIMM 10 th Mll Operators Conference, Adelade, Australa, October.The Australasan Insttute of Mnng and Metallurgy. Sh, F., Kojovc, T., Larb-Bram, S. and Manlapg, E Development of a new partcle breakage characterzaton 6 Copyrght 2013 by SME

7 devce the JKRBT.In Proceedngs of the Commnuton 2008 Conference, Falmouth, Cornwall, June Zemsk, M., Bye, A.,Plnt, N., Cole, M. andtordor, A An ntegrated geology-mne-plant and eco-effcency smulator for Anglo Platnum s evaluaton and operatonal mprovement ntatves.in Proceedngs of the XIX Internatonal Mneral Processng Congress, Brsbane, Australa, September 2010, AusIMM 7 Copyrght 2013 by SME