PlenaryLectures:Session I

PlenaryLectures:Session II

Movement ofCopper and

IndustrialOutlook:

Markets andTrends

CopperApplications

and Fabrication:Fabrication

CopperApplications

and Fabrication:Applications

Electrorefining:Refinery

Operations I

Electrorefining:Refinery

Operations II

Electrorefining:Refinery

Operations III

Electrorefining:Refinery

Operations IV

Electrorefining:Refinery

Anodes andCathodes

Smelting:Technology

Development I

Smelting:Technology

Development II

Smelting:Process Modeling

and Control I

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Smelting:Process Modeling

and Control II/Fundamental

Studies

Smelting:FundamentalStudies andTechnology

Development I

Smelting:FundamentalStudies andTechnology

Development II

Smelting:Process Modeling

andFundamentals:Gas Handling

Pyrometallurgy-Operations:

Session V

MineralProcessing:

Operations I

Hydrometallurgy:Ore Leaching

MineralProcessing:Metallurgy

MineralProcessing:

Operations II

Hydrometallurgy:Concentrate

Leaching I

Hydrometallurgy:Biohydro-

metallurgy

Hydrometallurgy:Metal Extraction

Environment,Health & Safety:

Session I

Hydrometallurgy:Design, Simulation

and Control

Hydrometallurgy:Concentrate

Leaching II

Hydrometallurgy:Electrowinning I

Pyrometallurgy-Operations:

Session I

Hydrometallurgy:Electrowinning II

Pyrometallurgy-Operations:

Session II

Pyrometallurgy-Operations:

Session III

AM PM AM AMPM PM

COPPER 99 - COBRE 99

Monday Tuesday WednesdayPo

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PlenaryLectures:Session III

Pyrometallurgy-Operations:

Session VI

Movement ofCopper and

IndustrialOutlook:

Economics-Finances

Pyrometallurgy-Operations:

Session IV

Electrorefining:Reactions During

Electrorefining

Environment,Health & Safety:

Session II

Pyrometallurgy-Operations:

Session VII

1

Plenary Lectures: Session I

Monday AM Room: Flagstaff/Goldwater/ Indigo/Jerome

October 11, 1999 Location: Pointe Hilton Resort

Session Chairs: G. A. Eltringham, BHP Copper, Inc.,Special Projects, San Francisco, CA 94104-1020 USA;P. J. Mackey, Noranda Technology Centre, PointClaire, Québec, Canada

8:30 AMWelcome Addresses by Co-Organizing SocietiesG. A. Eltringham representing The Minerals, Metals andMaterials SocietyS. Demetrio representing the Chilean Institute of Min-ing EngineersC. Diaz representing The Metallurgical Society of TheCanadian Institute of Mining, Metallurgy and Petro-leum

8:50 AMMarkets for Copper into the Millennium: A New Ap-proach to Copper Market Forecasting: Paul Dewison1;1Metalica Limited, Forge Cottage, Ousden, Suffolk CB88TR England For nine years, from mid-1987 to mid-1996, the cop-per market enjoyed what appeared to be an end-less boom in which prices were much higher relativeto production costs than for most other base metals.After the boom ended abruptly mid-1997 withSumitomo affair, copper was burdened by an over-hang of new projects that promised to swamp de-mand in what, with the Asian financial and economiccrisis of 1997, had become a considerably worse con-sumption environment. Now, demand prospects donot look so bad. If, as we suspect, we will be dealingwith a more rational market in the future, it becomesall the more important to forecast accurately the pros-pects for consumption. In this paper, we present anew methodology for copper demand forecasting.The methodology forms the backbone of the de-mand-side analysis for the multi-client study entitled“Long Term Outlook for Copper,” co-authored byMetalica Ltd. and Bloomsbury Minerals Economics(BME). Key components of the methodology are asfollows: relate demand to economic structure, focuson products rather than refined consumption, applya consistent products/applications analysis to allcountries and time series and incorporate scrap mar-ket dynamics within the analytical framework.

This Plenary Lecture will be preceeded by some ob-servations by Paul Dewison on recent developmentsin the Copper Industry regarding consolidation andcapacity changes.

10:00 AM Break

COPPER 99 - COBRE 99Final Technical Program

Electrorefining: Refinery Operations I

Monday AM Room: IndigoOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: J. E. Dutrizac, CANMET, Ottawa,Ontario, Canada K1A 0G1; V. Ramachandran,Asarco, Inc., Technical Service Center, Salt LakeCity, UT 84119 USA

10:30 AMElectrolytic Copper Refining - 1999 World TankhouseOperating Data: W. G. Davenport1; J. Jenkins2; B.Kennedy3; T. Robinson4; 1University of Arizona, Dept.of Mats. Sci. and Eng., Tuscon, AZ 85721 USA; 2CyprusSierrita Corporation, 6200 W. Duval Mine Rd., P.O. Box527, Green Valley, AZ 85622 USA; 3Simons Engineer-ing, Inc., 2700 N. 3rd St., Suite 2006, Phoenix, AZ 85004USA; 4CTI ANCOR, 2121 San Jacinta St., Suite 2500,Dallas, TX 75201 USA A survey of world copper refining tankhouse prac-tices has been carried out. This paper compiles theresults and examines changes in operating practicessince the similar 1987, 1991 and 1995 surveys. Con-tinuing trends are the installation of ISA Process andKidd Process stainless steel cathode technology, poly-mer concrete cells, anode preparation machines andautomatic cranes. Instrumentation and automaticcontrol are increasing, particularly for addition agentoptimization; solvent extraction and ion exchangetechniques are being increasingly applied for elec-trolyte purification. The overall consequences of thesechanges have been improved cathode purities andenhanced tankhouse productivities.

10:55 AMLa Caridad, the Newest Copper Refinery in the World:M. E. Ramos Rada1; J. M. Garcia R.1; I. Ramirez G.1;1Mexicana de Cobre S.A. de C.V., P.O. Box 20,Nacozari, Sonora CP 84330 México Mexicana de Cobre, which is part of GrupoMexico, carried out studies for the construction of acopper refinery in the La Caridad Metallurgical Com-plex located in Nacozari, in the state of Sonora,Mexico. After the studies were concluded, the deci-sion was made to construct a 180,000 t/y refinery us-ing the state of the art permanent cathode Kidd Pro-cess. The basic engineering was developed by FluorDaniel and the detail engineering and the construc-tion were carried out in record time by the Mexicancompany Bufete Industrial. During the constructionphase, Grupo Mexico decided to expand the refin-ery, and actions were taken to increase its capacityby an additional 120,000 t/y; the final result was arefinery capable of producing 300,000 tonnes ofgrade A cathode per year. Construction began in

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January 1996, and the operation of the first stagebegan on July 1, 1997. The operation of the secondstage commenced on January 7, 1998. The capacityof the first stage was reached in November, 1997 andthe total capacity of the refinery was achieved in May,1998. This presentation describes the process andequipment installed in the refinery, the steps leadingto the start-up, the operation and the results obtainedduring the first two years, the handling of anodes withhigh impurity contents, and the problems confrontedand the way they have been solved. It also includespersonnel productivity, the control parameters andthe most relevant data on the operation of the pro-cess.

11:20 AMDesign and Operating Characteristics of the New OlenTank House: C. Geenen1; J. Ramharter1; 1UnionMiniere Copper, Watertorenstraat 33, Olen B-2250 Bel-gium At its Olen site, Union Minière Copper operates anew full-size deposit tank house. A first 200,000 t/ymodule was commissioned in October 1996, and anadditional 130,000 t/y unit started in April 1998. Themain objectives of the new tank house project wereto produce grade A cathodes starting from anodeswith a wide range of compositions and at a minimaloperating cost. The tank house uses Isa Process tech-nology. Based on the process parameters agreedupon with MIM, UM Copper developed the basicdesign and UM Engineering was the in-house con-tractor for the engineering. The new tank house isequipped with advanced technology polymer con-crete cells, automated two-bale cranes and high-capacity machines. The first 200,000 t/y module treatsanodes with a more conventional composition at 330A/m˝; the second 130,000 t/y module treats anodeswith a high slimes fall (12-13 kg/t) at current densitiesup to 285 A/m˝. After some teething problems, thenew tank house is meeting all set targets. This paperillustrates and comments on the design characteris-tics and operational results.

11:45 AMDesign, Start-Up and Operation of the Cyprus MiamiCopper Refinery: J. Garvey1; B. J. Ledeboer2; J. M.Lommen3; 1Cyprus Miami Mining Corporation, P.O.Box 4444, Claypool, AZ 85532 USA; 2Electrometallurgi-cal Consultant, 3210 Melendy Dr., San Carlos, CA94070 USA; 3Fluor Daniel Mining and Minerals, 1527Cole Blvd., Golden, CO 80401 USA The new Cyprus Miami electrolytic copper refinerywas commissioned in October 1994. The refinery hasbeen operating at its design capacity of 190,000 shorttons per year, and in recent months to 110% of designcapacity, producing high-grade electrolytic coppercathodes. Basic and detailed engineering, performedby Fluor Daniel Mining and Minerals, Inc. state-of-the-art technology, including stainless steel cathodes,automated electrode handling, fine-filtering of thecommercial electrolyte, autoclave leaching of theanode slimes and other techniques. The major de-sign goals have been safety of operation and qual-ity of the product. Relatively high cathode currentdensities of 30 amperes per square foot and greaterhave been applied since start-up. Cathode currentefficiencies of over 94% have been achieved sincethe latter part of 1997. The cathodes were certified

on the Comex and LME markets during 1996. ISO-9002certification is in progress and should be completedduring the first quarter of next year. This report dis-cusses some of the studies that were performed toobtain an optimum layout for efficient materials han-dling and to create optimum conditions for produc-ing high quality cathodes. A description of the de-sign and operation of the anode slimes facility, in-cluding decopperizing with autoclave leaching, isprovided. Finally, a description of the start-up experi-ences and present operation of the electrorefineryare presented.

Hydrometallurgy: Ore Leaching

Monday AM Room: HopiOctober 11, 1999 Location: Pointe Hilton Resort

Session Chair: Henry Salomon-De-Friedberg,Compañia Minera Quebrada Blanca, Santiago,Chile S.A.

10:30 AMElectrolytic Copper—Leach, Solvent Extraction andElectrowinning World Operating Data: JacksonJenkins1; William G. Davenport2; Brian Kennedy3; TimRobinson4; 1Cyprus Sierrita Corporation, Tech. Svcs.Dept., Green Valley, AZ USA; 2University of Arizona,Dept. of Mat. Sci. and Eng., Tucson, AZ USA; 3SimonsEngineering, Inc., Metallu. Eng. Phoenix, AZ USA; 4In-ternational Business Development, Cti Anchor, Dal-las, TX USA The second survey of world copper SXEW plantshas been completed. Solvent extraction and electrow-inning data published in 1996 has been updated andleach data from seventeen plants is now included.The results of the thirty-two plants that responded tothe survey are presented. Selected information is sum-marized in graphical form.

10:55 AMRecent Changes to Operating Practices at MineraQuebrada Blanca: Henry Salomon-De-Friedberg1;1Compañia Minera Quebrada Blanca S.A., Apoquin-do 3200, 4° Piso, Santiago, Chile Quebrada Blanca has had to overcome numer-ous challenges in achieving design throughput. Thepaper reviews how actual practice has evolved fromthe original design. The major challenges that wereencountered from heap leeching to solvent extrac-tion, the tankfarrn and through to electrowinning arediscussed. The eventual solutions to some of the keyissues are presented.

11:20 AMEnhanced Leaching of Copper Sulfide Leach Dumps:Application at Cananea, Mexico: Jose HectorFigueroa P.1; Jorge Enrique Ruiz H.1; Ramon Ayala F.1;1Mexicana de Cananea, S.A. de C.V., Av. Juarez No.4, Cananea, Sonora 84620 Mexico Mexicana de Cananea, S.A. de C.V. is a majorcopper producer mining a large deposit of the dis-seminated porphyry type considered one of the larg-est copper resources of the world with 2.7 billion tons

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of 0.60% copper for the mill plus 4.1 billion tons ofaveraging 0.26% copper for leaching. Mining of lowgrade sulfide leach ore, has been an important partof the overall production of the open pit mine whichstarted in 1944. Before this time all the mining inCananea was by underground methods. The leach-ing process in Cananea began on the 1920’s with insitu operations in the underground mine and smalldumps up to the 1950’s. Large scale leaching opera-tions began in 1960 and the copper solutions pro-duced were treated in precipitation plants until 1980when the first SX/EW Plant was put in operation inCananea. Leaching action is essentially ferric-bacte-rial, with no fresh acid added to the leaching solu-tions. Traditionally, 55-60% copper extraction is recov-ered from ROM, 70-120 meter high leach dumps in 80months of leaching. Cananea has successfully im-proved copper recoveries by implementing severalactions that include: stripping of old dumps, leach-ing of old dumps through slotted casing, and crush-ing conveying leach ore to minus 8 inch and stack-ing it in 30 meter lifts. As result of these actions, cop-per recovery has been increased to about 70% of totalcopper with actions 1 and 2 and up to 85% in half thetime by crushing-conveying the leach ore, based onthe same solubility index of the run-of-mine ore. Thispaper describes the above actions that were imple-mented to enhance the leaching recoveries from sul-fide leach dumps and the economics of such actions.

11:45 AMDesign Modifications at Zaldivar to Reach Plant Ca-pacity Production: C. Garcia1; H. Arias1; J. Campos1;S. Gonzalez1; J. Mallory1; G. Merino1; J. Roco1; O. SanMartin1; J. Whittaker1; 1Compañia Minera Zaldivar,Balmaceda 2536, 4° Piso, Antofagasta, Chile Several modifications to Zaldivar’s original designhave been made in order to reach the design cath-ode production. This paper describes the modifica-tions to the crushing, leaching, solvent extraction andelectrowinning operations, which in turn have in-creased the production by 14.8% over the design ca-pacity in 1999. The principal modifications were to(1) incorporate a dry prescreening plant between thesecondary and tertiary crushers to increase the per-centage of fines to the piles, (2) increase the reten-tion time of the solutions inside of the piles, and (3)increase the efficiency of the tertiary crusher’s to re-duce the particle size of the product material. Theleaching ratio was increased from 2.8 to 5.6 m3/ton.The temperature of the pregnant leach solution (PLS)was increased, the amount of acid used was reduced,and a strain of native bacteria was adapted in highlycontaminated solutions. The copper concentrationin the PLS was increased by more than 50% and wasstabilized at this level by commissioning a process oftwo-stage leaching. The current density in thetankhouse was increased from an average of 216 to317 A/m2.

12:10 PMHeap Leaching Practices at San Manuel Oxide Op-erations: Joel K. Witt1; Phil E. Cantrell1; Manuel P.Neira1; 1BHP Copper, San Manuel Oxide Operations,28255 W. Redington Rd., P.O. Box M, San Manuel, AZ85631 USA San Manuel Oxide operations of BHP Copper, lo-cated in Southeastern Arizona, operates a leach-sol-

vent extraction/electrowinning (SXEW) facility thatproduces high quality cathode copper from low-grade oxide ores. Permanent heap leaching and in-situ leaching methods accomplish the dissolution ofcopper from the oxide ores. Open pit mining andheap leach construction took place from 1985 to 1995.Run-of-mine oxide ore from the pit was hauled to theheap dumps and leached by the soaking cure andcontinuous irrigation method. Solution application tothe heaps still continues and acid soluble copper re-covery has reached 86%. This paper presents and dis-cusses the current operating practices and innova-tions applied to the leach facilities to maximize cop-per recovery from the heap leached residue. Factorssuch as irr igation methods, solution chemistry,sideslope treatment, post curing, lixiviant acid strength,and “rice paddies” irrigation, will be discussed. Heapleach solution control and sampling methodologieswill be also presented.

Hydrometallurgy: Concentrate Leaching

Monday AM Room: Apache/BisbeeOctober 11, 1999 Location: Pointe Hilton Resort

Session Chair: David Dreisinger, University of BritishColumbia, Vancouver, Canada BC V6T 1Z4

10:30 AMLeaching of Copper Concentrate by a ChemicalCatalytic Oxidation Method: Burkhard Seeger1;1Universidad de Concepción, P.O. Box 160-C,Concepción, Chile The oxidation of copper sulfides can be highlyaccelerated in the presence of nitrous gases (NOx) asreaction catalysts. Sulfur and sulfate are simultaneouslyproduced in this highly exothermic reaction. This pro-cess, carried out in sulfuric acid medium, is performedat an approximately normal pressure and at a tem-perature of around 110ϒC, in a closed container,adding either oxygen or air. The oxidation is auto-matically controlled through a computer. The pro-cess covers the following steps: Catalytic oxidation,filtration and crystallisation of the hot concentratedliquid, electrowinning, mother l iquor treatmentthrough jarosite formation, recovery of dissolved cop-per and zinc and regeneration of industrial water, andnon-soluble residue treatment with extraction of sul-fur and recovery of silver and gold. No combustiblesare needed. No air is contaminated, and no waste-water is produced. Solid residues are in a stable, non-toxic and non-corrosive state of equilibrium. Risk ofaccident is low. Investment costs are small comparedto those of the comparable pyrometallurgical pro-cess, and production costs are competitive.

10:55 AMThe Treatment of Chalcopyrite Concentrates with Ni-trogen Species Catalyzed Oxidative Pressure Leach-ing: Corby G. Anderson1; 1Montana Tech, The Cen-ter for Adv. Min. & Metall. Process., Rm. 221 ELC Bldg.,Butte, MT 59701 USA Today, with a stringent economic and environmen-tal climate prevailing in the copper business, there is

4

increased interest in evaluating new processing alter-natives for production. Hydrometallurgical pressureoxidation of copper concentrates is one of the moreviable approaches and several technological can-didates have emerged. Of these, an overlooked butindustrially proven methodology utilizing nitrogenspecies catalyzation in the oxidizing pressure leachsystem may prove to be a feasible process alterna-tive for the future. In this paper, the history of the sys-tem and its application to chalcopyrite concentrateswill be outlined. In particular, a methodology for ef-fective treatment of precious metals bearing chal-copyrite concentrates via partial oxidation at lowtemperatures and pressures will be discussed. Finally,the perceived economics of this unique industriallyproven process will be delineated.

11:20 AMNew Atmospheric Leach Process for Copper SulfideOres and Concentrates: C. J. Ferron1; N. McKay1; L.Dymov1; D. Butcher1; 1Lakefield Research Limited, 185Concession St., Postal Bag 4300, Lakefield, Ontario,Canada KOL 2H0 Over the years, numerous hydrometallurgical pro-cesses have been proposed as an alternative orcomplement to smelters for the treatment of copperconcentrates. Most of these initiatives met with lim-ited success. Bioleaching is applied commercially forsecondary copper minerals heaps and dumps, andbacterial leaching processes are being developedfor copper concentrates, although industrial appli-cation is still years away. More recently developedprocesses usually include pressure leaching and/orultrafine grinding. This paper proposes a new leachprocess to treat copper sulfide ores or concentrates:the process operates under atmospheric pressure anduses limited concentrations of ferric sulphate as oxi-dant; the key to the process is the regeneration of theferric ion, which can be effected in-situ (direct pro-cess) or ex-situ (indirect process) using SO2/O2. Ex-amples are presented for the treatment of copper con-centrates by agitation leach and of copper ores byheap leaching. Application of the process to cop-per gold ores and chalcopyrite concentrates is alsodiscussed.

11:45 AMPressure Leaching of Chalcopyrite Concentrates byDynatec: Leslie A. Barta1; Kelvin R. Buban1; JohnStiksma1; Michael J. Collins1; 1Dynatec Corporation,Metall. Tech. Div., 8301-113 St., Ft. Saskatchewan,Alberta, Canada T8L 4K7 A new process for the leaching of chalcopyriteconcentrates has been developed and tested inminiplant campaigns and locked cycle testwork car-ried out between 1996 and 1999. The process involvespressure leaching in a sulphuric acid solution, e.g.raffinate from copper solvent extraction. Iron in thefeeds is precipitated predominantly as hematite in theautoclave, simultaneously with copper extraction.Gold and silver in the pressure leach residue are re-coverable by conventional cyanidation, followingflotation to remove elemental sulphur by-product. Theresults of recent miniplant tests and batch lockedcycle tests are provided.

12:10 PMThe Total Pressure Oxidation of El Indio Ore and Con-centrate: David B. Dreisinger1; Benjamin R. Saito2; 1TheUniversity of British Columbia, Dept. of Metals andMats. Eng., 6350 Stores Rd., Vancouver, Canada BCV6T 1Z4; 2BHP Copper, San Manuel Refinery, 200 S.,Redington Rd., P.O. Box M, San Manuel, AZ 85631 USA The total pressure oxidation treatment of arsenicalcopper ore and concentrate from the El Indio mineof Barrick Gold was tested in benchtop autoclavetreatment. The concentrate oxidation typicallyachieved ~95% copper extraction. Copper extractionwas limited by the reprecipitation of a complex pre-cipitate containing arsenic. Gold extraction bycyanidation of the oxidation residue was around 95%.Silver extractions were less than 10% due to the for-mation of argentojarosite in the autoclave. The totalpressure oxidation of the whole ore sample was moresuccessful. Copper extractions of 98-99% were rou-tine achieved. Gold extraction by cyanidation was+95%. Silver extraction could be increased to as highas 95% by using the lime boil treatment. A processflowsheet was proposed based on the resultsachieved. Copper recovery was proposed by directsolvent extraction and electrowinning of copper bytreating the dilute solution from the autoclave dis-charge.

Mineral Processing: Operations I

Monday AM Room: JeromeOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: Mark O'Brien, Phelps Dodge; EricGutierrez

10:30 AMAdvances in Computer-Based, Multimedia TrainingProvide Significant Opportunities to Improve Results:Stephen R. Brown1; 1Performance Associates Interna-tional, Inc., 760 E. Pusch View Ln., Tucson, AZ USA Current conditions in the copper market demandthat mine and plant operators make budgeted pro-duction targets at the lowest possible unit costs. Forthose companies bringing new production capacityon-line, achieving budgeted production levels asquickly as possible after start-up is vitally important tominimize unit costs and to begin a positive cash flow.Whether the objective is to simply improve unit costsor successfully start-up a new, complex plant, suc-cess will be strongly influenced by the skill levels ofthe operators and supervisors. The only way to assurereturn on plant investment, and to survive during de-pressed metal prices, is to ensure that plant operatorshave the knowledge to effectively run the plant. Tech-nology available in computer-based, multimediatraining systems, including: interactive animation, vid-eos, voice-overs, schematics, and text can now beused to train operators at their own pace using plant-specific information. Additionally, it has been shown

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that learning through multimedia provides a higherdegree of long term retention than more traditionallearning methods.

10:55 AMCopper Ore Preconcentration by Heavy Media Sepa-ration for Reduced Capital and Operating Costs:Walter E. McCulloch1; Roshan B. Bhappu2; John D.Hightower2; 1Bateman Engineering, Inc., 305 S. EuclidAve., Suite 111, Tucson, AZ 85719 USA; 2Mountain StatesR and D International, P.O. Box 310, Vail, AZ 85641USA Recent laboratory bench scale and pilot plantmetallurgical tests at Mountain States R and D Inter-national have demonstrated that some copper oresbecause of relatively coarse copper sulfide mineral-ization can be preconcentrated by heavy mediaseparation (HMS). In tests with a copper ore from theAMT Copper Creek project near San Manuel, Arizona,HMS preconcentration rejected about 75 to 80 per-cent of the feed as a minus 13 mm gravel. The HMSconcentrates copper recoveries were about 93 to 95percent. With the incorporation of HMS preconcentra-tion, significant capital and operating costs savingshave been projected for the proposed AMT CopperCreek concentrator. An overview of the HMSpreconcentration step development for the AMTCopper Creek project is presented. Also presentedare other potential applications of HMS preconcen-tration for copper ore processing.

11:20 AMAdvances in Application Driven Design of FlotationCells: Jouko Kallionen1; 1Dorr-Oliver, Inc., 333 SouthAllison Pkwy., Suite 304, Denver, CO 80226 USA Advanced Flotation Technology is the applicationdriven design of flotation cells to achieve the opti-mum performance for each type and grind of flota-tion. This can be applied to roughers, scavengers,cleaners and specialty cells such as those to floathydrocyclone underflows in both primary and regrindcircuits in order to reduce overgrinding. Standard,engineered, components are matched to providemechanism design and cell dimensions for each caseaccording to feed parameters and flotation type.Advances in process control have been achievedwith high level controls and operator informationdata. This has gained a higher degree of understand-ing of cell operation and ore type being processed.Excellent results of this Advanced Flotation Technol-ogy in large scale porphyric copper ore have beenachieved and designs through 7000 cu ft (200 m3) arecurrently available for high capacity concentrators.This paper will detail how flotation cells are more re-sponsive to the exact requirements of the duty speci-fied.

11:45 AMOptimisation of the Phosphate Nokes Process at theEl Teniente By-Product Molybdenite Plant: S. H.Castro1; C. Henriquez2; E. Beas2; 1University of Concep-ción, Dept. of Metall. Eng.; 2Codelco-Chile, El TenienteDivision (MINCO) The El Teniente molybdenite plant (Chile), with anominal capacity of 3,200 tpd of bulk Cu-Mo con-centrate, produced approximately 3,385 metric tonnes

of Mo during 1998 by using the Phosphate Nokes Pro-cess (LR-744 reagent). This is the only Chilean molyplant which traditionally has depressed copper andiron sulfides with LR-744 reagent, which is a hydrolysisproduct of P2S5 NaOH. El Teniente’s ore Mo grade is0.02%Mo and is concentrated to 0.45%-0.50% Mo inbulk Cu-Mo flotation. Subsequently, molybdenite isfloated by selective flotation to depress Cu and Fesulfides, such as chalcopyrite, bornite, digenite andpyrite, to produce typically a 49%-50% Mo molybden-ite concentrate. An optimisation program during thelast two years was undertaken to improve molybden-ite recoveries. Current molybdenite plant technologyat El Teniente and the use of Phosphate Nokes in theprocess is reported. Use of phosphate Nokes reagenthas increased average Mo recovery from 70.5% in1977 to a mean of 74.7% for the first 4 months of 1999.The global Mo recovery, including bulk flotation, in-creased from 42.3% in 1997 to 46.8% in 1998, with aprojection of 55.5% for 1999. Mo production per yearhas increased from 3,181 tons in 1997 to 3,385 tons in1998 and a projected 4,000 tons for 1999.

12:10 PMPlant-Wide Process Control for the Collahuasi Project:Alex Del Castillo1; Patricio Gomez1; 1OCS, IndustrialSystem Div., ABB, Chile The mineral processing industry has followed thedevelopment of database control systems, and vari-ous systems have been installed in existing and newplants. The goal is to improve product quality, raiseproductivity and lower production costs. Improve-ments in different units for mineral processing havebeen applied. This has led to increasing informationfor the operators. To support the operators and foran easy overview of the process, a complete con-cept for an integrated process-control system is re-quired. This paper describes the plant-wide processcontrol system for the Collahuasi copper project lo-cated in northern Chile. The total investment for theproject was $1,700,000,000 and included a port areaand two copper processing plants, an oxide plantwith a cathode production of 50 tons per year and asulfide plant with a concentrate production of 330kilotons per year. The main characteristics of the plant-wide process control system include a 200-kilometerlong redundant control network and a 24-kilometerlong redundant serial network providing coveragefor the entire plant. The plants are located around4,700 meters above sea level, serial communicationlinks allow the integration of over 2,700 SCADA dataunits, and the system handles over 7,500 physical sig-nals plus the SCADA data integration. The main equip-ment consists of 39 different sized controllers, 16 op-erator stations, 5 engineering stations, 2 informationmanagement systems and 4 X-terminals. The projectmanagement, control configuration, factory accep-tance test, system integration test, training, commis-sioning and start-up were carried out in close coop-eration with the customer. The result was completelysatisfactory for the customer.

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Movement of Copper and IndustrialOutlook: Economics-Finances

Monday AM Room: CopperOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: Peter Kettle, CRU International Ltd.,Base Metal Business Unit, 31 Mount Pleasant, Lon-don WCIX OAD, England; Gary A. Campbell,Michigan Technical University, SBE, 1400 TownsendDr., Houghton, MI 49931 USA

10:30 AMRisk Management in the New Millennium: John M.Rogers1; Michael Chubb1; 1SGS Mineral Services, 97,rue de Lyon, P.O. Box 2152, Geneva 1 CH-1211 Swit-zerland Risk management has rapidly developed to be-come an integrated, holistic approach that now en-compasses the main risk elements such as productquality control, occupational health and safety, se-curity, environmental liability, social issues, and re-lated management information systems. Given theobvious economic benefits, a seamless blend of riskmanagement components has become essential toallowing organisations to sustain a competitive ad-vantage, and is also looked upon as an importantattribute in organisational growth. Juxtaposed withthis management philosophy is the global trend to-wards outsourcing, which has seen the emergenceof independent, and specialist risk managementorganisations. The New Millennium will undoubtedlysee a shift away from “in-house” risk managementpractices, and consequently, the selection of a suit-able risk management partner—a major vehicle forimproving shareholder value—will become an impor-tant strategic management decision.

10:55 AMBenefits of Private Mining in Chile: The Case of MineraEscondida: Gustavo E. Lagos1; Marcelo E. Andia1;Guillermo Donoso2; 1Catholic University of Chile, Ctr.for Mining, Vicuña Mackenna 4860, Avda. Macul,Santiago, Chile; 2Catholic University of Chile,Agronomy Dept., Avda. Vicuña Mackenna 4860,Macul, Santiago,Chile Mining is one of the oldest and most important pro-ductive activities in Chile. In the latter half of the 80’sand during the 1990’s Chilean mining has experiencedexplosive growth fundamentally due to legislativechanges which have encouraged an influx of foreigncapital. Fine copper production has grown from 1.4million tons in 1987 to 3.4 million tons in 1997. Goldproduction has increased from 17.03 tons in 1987 to49.46 tons in 1997. In both cases private investmenthas driven this growth. The direct impact of miningon the Chilean economy has been considered oneof the fundamental pillars of the growth of the coun-try in the last years. The indirect impact that has gen-erated on the other sectors of the Chilean economyand in particular the regional economies, has notbeen analyzed. This paper outlines a methodologyfor estimating the impact of mining investment andmining operations in different sectors of the Chilean

economy at both regional and national levels. Itapplies this methodology to the case of MineraEscondida, the largest copper mine in the world,analyzing its economic impacts on the regional andnational levels.

11:20 AMMaking Outsourcing Decisions with IncrementalAnalysis: Bruce Cavender1; 1BHP Copper, Inc., P.O.Box M, San Manuel, AZ 85631 USA Managers are frequently faced with the decisionto perform a task or manufacture an object in-houseor to hire an outside vendor to perform the function.Outsourcing decisions are usually driven by econom-ics: work is outsourced if it can be completed at alower cost or in a shorter time than it can in-house. Atechnique termed incremental analysis can be usedto make this decision. Incremental analysis examinesthe financial impact of outsourcing decisions as afunction of the firm’s fixed and variable operatingcosts. To use this tool, individual components of pro-duction cost are identified as being either constantor varying with levels of production activity. The as-signment of cost type can be made in several ways:through analysis of historical operating data, under-standing of individual expense types, and so forth.Changes in fixed and variable costs resulting fromeach potential course of action are explicitly identi-fied to project the financial outcome of each alter-native. The alternative having the greatest positiveimpact on profit is selected for implementation. Byusing the fixed- and variable-cost framework, theanalysis is conceptually straightforward and substan-tially simplified. Production managers can thereforeuse incremental analysis as a tool for fast and eco-nomically beneficial decisions on a real-time basis.

11:45 AMProject Phasing and the Bottom Line: C. Twigge-Molecey1; D. Dawson1; 1Hatch Associates, 2800Speakman Dr., Mississauga, Ontario, Canada L5K ZR7 All projects that are implemented, have been givencorporate go-ahead on the basis of a set of clearlydefined targets. These are typically a production goalat a capital cost, operating cost and productionschedule, that will yield an acceptable return on in-vestment by the companies internal criteria. The chal-lenge for the implementation team is two-fold, firstlyto properly define the project criteria prior to boardapproval and secondly to deliver an operating facil-ity that meets these objectives, in particular the R.O.I.The paper addresses the issues a project team andthe company management must address for a suc-cessful project. Key questions that will be exploredare: What is the status of key technologies?; Are theywell proven in commercial practice, completely novelor in between?; Is the project schedule driven bymarket constraints or cash flow constraints?; Are therisks of fast tracking worth the potential rewards?; Fora retrofit project, are all the technical and produc-tion interfaces and issues known at the time of ap-proval to proceed?; How much should be investedin technological development and engineering andat which phase?; For owner-operator, how much re-sponsibility is it wise or appropriate to push down tovendors? The answers to these questions for a spe-cific project will define how you go about a project,the resources required, the contracting strategies, the

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phasing and the appropriate level of investment inthe definition and procurement phases, prior to start-ing major capital commitments and construction.

12:10 PMThe Price-Stock Relationship in the Copper Market: ASurprising Approach: Pablo Pincheira Brown1;1Comisión Chilena del Cobre, Div. of Policy Plann-ings, Agustinas 1161, 4° Piso, Santiago, Chile The widely accepted inverse relationship betweencopper prices and stocks has been commonly usedby analysts to explain the behaviour of the coppermarket and to forecast future copper prices. How-ever, empirical data have not shown such a clearrelationship between copper prices and stocks. Exist-ing evidence only indicates a weak long-run relation-ship that vanishes in some periods. In this paper asimple comprehensive model is provided, which ex-plains both parallel and opposite direction move-ments between prices and stocks. Former are ex-plained mainly by stocks demand expansions-con-tractions while the latter are in essence due to in-creases in the supply curve. Furthermore, economet-ric estimations are provided, thus giving a powerfultool to forecast and explain price developments ofthe copper market.

Pyrometallurgy-Operations: Session I

Monday AM Room: EstrellaOctober 11, 1999 Location: Pointe Hilton Resort

Session Chair: David George; Kennecott UtahCopper, Salt Lake City, UT USA; Sergio Demetrio,ConOpti S.A., Cerro San Ramon 1491, Las Condes,Santiago, Chile

10:30 AMModernizaton of the Luanshya Smelter, Zambia:Abhoy Mukherjee1; Carlos L. Boetsch2; Antonio A.Luraschi2; 1Roan Antelope Mining Corporation ofZambia PLC, P.O. Box 90456, Luanshya, Zambia, Cen-tral Africa; 2INDEC, International Engineering Consult-ing Services, Avda. Providencia 2653, Of. 512,Santiago, Chile The Luanshya Smelter is a traditional ReverbaratorySmelter which once worked with up to three coal-fired reverbs, and now operates one Reverb and onehot Peirce-Smith Converter, projected to produce ap-proximately 42,000 tons per year of copper anodes.The aim of this study is to select a smelting technol-ogy which best fits the upgrading of the Smelter, suchthat low capital and operating costs are achievedfor the projected design production capacity of60,000 tpy, limited by the available supplies of con-centrates. An equally important requisite is the com-pliance of present and future environment regula-tions, which determines the need to install and AcidPlant to treat the smelter primary gases. In the pro-cess selection study, the following technologies wereanalyzed, at a Conceptual Engineering level: the Oxy-fuel Burner Reverb, the Teniente Converter, theCONTOP Cyclone Smelting Reactor, and further, theAusmelt Furnace, the engineering of which was pro-

vided by the proprietary firm. The engineering of theother processes was developed by INDEC, which alsointegrated the comparative analysis of the four op-tions. The analysis of a comprehensive set of techni-cal factors, including integrated smelter metallurgi-cal models, together with the evaluations of economi-cal features, led to the selection of the CONTOP Smelt-ing Technology for the modernization of the LuanshyaSmelter.

10:55 AMHernán Videla Lira Copper Smelter Modernization: Or-lando C. Rojas1; J. A. Sanhueza1; 1Empresa Nacionalde Minería, Fundición Hernán Videla Lira, Copiaoó,Tercera Region, Chile Improvements and modifications of layout andprocess, from 1997 until 1998, are presented. Basedon an Teniente Converter, started up in 1993, a Strate-gic Development Plan was structured to increase theproduction efficiency and comply with the environ-mental regulations too. It considered the oxygen sup-plies to the Teniente Converter and Peirce Smith con-verters; reverberatory furnace shut down as a smelt-ing unit; and the Teniente converter slag treatmentthrough a combined process between a Slag Settlerfurnace and flotation. Also it included the off-gashandling and treatment.

11:20 AMRecent Operation and Environmental Control in theKennecott Smelter: C. J. Newman1; D. N. Collins1; A.J. Weddick1; 1Kennecott Utah Copper Corporation,8315 West 3595 South, P.O. Box 6001, Magna, UT 84044-6001 USA The new Kennecott Utah Copper smelter, startedin 1995, was designed to be the most clean smelterenvironmentally in the world. The plant is operatingat production rates above the original design capac-ity. Copper concentrate is smelted in an Outokumpuflash smelting furnace. Matte is granulated and pro-cessed using Kennecott-Outokumpu flash converting.Copper anodes are processed in a modernized cop-per refinery using the Kidd Process while anode slimesare processed for precious metals recovery using aunique hydro-metallurgical process. To allow the pro-duction of high quality cathode, using modem smelt-ing and converting technology to minimize emissions,impurity control had to be carefully addressed. Allprocess bleed streams from the smelter and refineryare treated in a hydro-metallurgical plant to fix impu-rities in a stable form, allow for the rejection of impu-rities as required and recover valuable metals. Spe-cial technology was developed for the copper refin-ery to ensure production of high quality cathode fromanodes containing high levels of impurities. Thesmelter routinely achieves a sulfur capture in excessof 99.9% which is equal to less than 2 kg of S02 pertonne of copper produced. This paper describes thedesign of the smelter and refinery and includes re-cent production and emission data and modifica-tions carried out to allow operation at above the origi-nal design rates. It emphasizes the unique featuresrequired to achieve environmental and quality goalsand compares environmental performance data tothat published on other smelting operations. The pro-cessing of intermediate streams, the management ofrecycled materials and the impurity control strategywill be covered in detail.

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11:45 AMNew Strategic Scope of the Caletones Smelter Devel-opment: Ruben Alvarado1; Jorge Godoy1; 1Codelco-Chile, El Teniente Div., Caletones Smelter, Caletones,Rancagua, Chile The need to increase business competitivenesswhile complying with environmental requirementsrepresent the great challenge that the Caletonessmelter has decided to face in a new developmentproject with a compromising and willing alliance withits workers. To date, the project is at the feasibilitystage, with start up scheduled for the middle of theyear 2002. The processing capacity of the TenienteConverters will be increased to levels up to 2400 tpdof chalcopyrite-based concentrates containing 30%Cu, by means of more intensive use of oxygen andimproved stabilization of the overall operation. Pro-ductivity increases in the converting of white metaland the pyrometallurgical treatment of slag are alsoplanned. As a result of related strategies, the produc-tivity of the supporting facilities, included the capac-ity of the sulfuric acid plants, will be increased. Anintensive and well-designed labor-upgrading schemewill allow the transformation of every worker into anexpert in his working areas, thus becoming an activedriving force in technology development. Mechani-zation, appropriate infrastructure, and complete pro-cess control and instrumentation will give to the skilledand motivated personnel the necessary tools in or-der to attain the highest potential ever reached withthe Teniente technology. The necessary investment forthis project based on the adding facilities to the exist-ing plant is only a third of that required to reach thesame objective for a greenfield plant, thus yielding avery high return on investment.

12:10 PMCopper Smelting and Refining in Indonesia: ShunichiAjima1; Koichi Konda2; Kiyoshi Kanamori2; ToshihikoIgarashi2; Tatsuya Muto2; Shosaku Hayashi2; 1PT Smelt-ing Company, Plaza 89, 6th Floor, S-602, HR RasunaSaid Kav. X-7, No. 6, Jakarta 12940 Indonesia; 2PTSmelting Company, Gresik Smelter & Refinery, DesaRoomo, Kecamatan Manyar, P.O. Box 555, Gresik,Jawa Timur 61151 Indonesia PT Smelting Company was established in February,1996 to construct and operate the Gresik Smelter andRefinery. The construction work of the first CopperSmelter and Refinery in Indonesia was completed inthe end of August, 1998 and it was put into the inte-grated test operation in December, 1998. GresikSmelter and Refinery is designed to produce 200,000tpy of copper cathode from copper concentrate sup-plied from Grasberg Mine of PT. Freeport IndonesiaCompany in Irian Jaya, Indonesia. As by product592,000 tpy of sulfuric acid, 382,000 tpy of slag, 31,000tpy of gypsum and 480 tpy of slime will be producedin the full operation. Major processes applied at GresikSmelter and Refinery are: Smelter: Mitsubishi Continu-ous Copper Smelting and Converting Process(Mitsubishi Process); Anode Casting: ContinuousCasting of Copper Anodes with the Hazelett Twin BeltCaster; Refinery: ISA Process; Acid Plant: Lurgi Mitsu-bishi Double Contact Process.

12:35 PMTechnical Improvement and Modification of GuixiSmelter in Recent Ten Years: Yuan Zeping1; Bai Meng2;

1Guixi Smelter of Jiangxi Copper Corporation,Changsha China; 2Center South University of Tech-nology (CSUT), Changsha, China The Guixi smelter is the first Outokumpu flash smelterin China. It was commissioned on December 31, 1985.Originally, the smelter was designed to produce 90,000tonnes of copper annually. After the implementationof oxygen enrichment and other modifications, thesmelter will reach its anticipated annual capacity of200,000 tonnes of copper in December, 1999. This pa-per describes the performance of the smelter, the firstphase modification project and the second phaseexpansion project which have made Guixi one of thebest copper smelters in the word through the use ofexisting and innovative technologies.

Smelting: Technology Development,Process Modeling and Fundamentals:Technology Development I

Monday AM Room: GoldwaterOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: C. M. Diaz, University of Toronto,c/o Dept. of Metallurgy and Matls. Sci., Toronto,Ontario, Canada; A. J. Weddick, Kennecott UtahCopper Smelter, 12000 West 2100 South, Magna, UT84011 USA

10:30 AMCopper Smelting in the 21st Century: Nickolas J.Themelis1; 1Columbia University, Earth Engr. Ctr., 500West 120th St., New York, NY 10027 USA The role of copper in the economy will not dimin-ish in the 21st century. Following the tenets of indus-trial ecology, production and use of copper must takeinto account both human needs and also how tominimize “collateral” effects on the environment. Dis-persive uses will be phased out and post-use recov-ery of copper will increase. This will result into an ad-vantage for smelting processes that can accommo-date mixed metal scrap and waste streams. The bathsmelting processes of Noranda and Mitsubishi willcontinue to make progress but the dominance of theOutokurnpu flash smelting will not be challenged untilthe Noranda reactor overcomes the obstacles to thedirect production of copper, thus eliminating the needfor a converter.

10:55 AMSingle Stage Copper Making-Flowsheet Development:M. Somerville1; T. Norgate1; P. Jefferies1; A. Vecchio-Sadus1; S. Jahanshahi1; 1GK Williams CRC for Extrac-tive Metallurgy, CSIRO Minerals, P.O. Box 312, ClaytonSouth, Victoria 3169 Australia In 1989 CSIRO Minerals initiated investigations intocontinuous converting of copper matte into low sul-phur blister in Sirosmelt type reactors. Following thesuccessful piloting of this processing route, some ef-fort was directed towards a single stage copper mak-ing process where copper metal is made in one stepfrom concentrate. The aim of the project is to de-velop a continuous process, which offers consider-

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able environmental and economic benefits over con-ventional copper making processes, which use Pierce-Smith converters. In the selection of the optimumflowsheet a number of slag treatment operations havebeen considered and tested. These unit operationsinclude: leaching and electrowinning, floatation-leaching-electrowinning and floatation with recyclingof recovered copper through the smelting vessel. Inthis paper the suitability of these process options areevaluated using the available information and re-cently measured copper recoveries from our testworkat CISRO. The operating and capital costs of the vari-ous options have been estimated using Aspen Plussimulation procedures. The most attractive flowsheetin terms of capital and operating costs is the treat-ment of slag using mineral processing techniques andthe recycle of a copper slag concentrate to the smelt-ing vessel. It has been found that the chemistry of theslag being treated has a large bearing on the recov-ery of copper in flotation and hence on the econom-ics of the process.

11:20 AMOne Step Forward, Two Steps Back: Crackpots, Char-latans and Metallurgical Absurdities in the Develop-ment of Smelting Technology: Larry M. Southwick1;1L. M. Southwick & Associates, 992 Marion Ave., Suite306, Cincinnati, OH 45229 USA The smelting of copper and other non-ferrous met-als have made considerable advances over the last125 years. Many of the ideas and processes currentlyin use were attempted early in the history of smeltingand were unsuccessful. Often the cause was incom-plete understanding of the metallurgy involved, in-adequate refractories, poor materials of equipmentfabrication or trying too many new ideas at once.With time, these problems get solved and the tech-nologies become commercialized. These were pro-cesses whose time had not come when originally pro-posed, but did eventually. On the other hand, therehave been some concepts whose time will nevercome. They were impossible then and they are im-possible now. The people that dream these up wereeither crackpots (they didn’t know what they weredoing, but thought they did), or charlatans (they knewthey didn’t know what they were doing, but didn’tcare). Both rely on bad science to propose metallur-gical absurdities. These too have their place in thedevelopment of technology, though mostly negative,and several examples will be discussed in this paper.Three from around the turn of the century will be cov-ered, as well as one from this decade. The last dem-onstrates that the art of creating absurdities has notwithered, even after ninety years of scientific sophisti-cation, and some can even be patented. The firstthree reached field trials due to the gullibility of com-pany management. The last arose from a fortuitousmis-operation of a plant which solved a problem, butthe explanation and patent which arose are metal-lurgically impossible.

11:45 AMComputerized Fluid Dynamic (CFD) Modeling, anImportant New Engineering Tool for Design of Smelt-ing Furnaces: Jonathan M. Berkoe1; D. M. (Mike)Lane1; Brigette M. Rosendall1; 1Bechtel Corporation,Min. & Metls. Tech., P.O. Box 193965, San Francisco,CA 94119-3965 USA

Design engineers and metallurgists have long rec-ognized the need for better methods to calculate awide range of fluid dynamic effects in smelters andhydrometallurgical facilities. Examples can range fromthe capture of fume in the secondary hoods of acopper converter, to controlling the thermal effectsof heat transfer resulting from metal and slag flowswithin a furnace. With the advent of relatively low-cost, high-speed computers and user-friendly, com-mercially available computerized fluid dynamic (CFD)programs, these calculations can now be made. Useof CFD increased the understanding of both hot gasand molten flows in smelter facilities and has alreadyled to design improvements in converter fume con-trol hoods as well as improved management of heattransfer in electric furnaces. This paper will present tworepresentative CFD applications to metals industryfacilities. To date, Bechtel has implemented CFD re-sults on four continents.

12:10 PMApplication of Composite Furnace Module CoolingSystems in a Flash Furnace Reaction Shaft: AndrewK. Kyllo1; Neil B. Gray1; Diamond Papazoglou2; B. J.Elliot2; 1The University of Melbourne, GK Williams Co-operative Rsch. Ctr. for Extract. Metallu., Dept. ofChem. Eng., Parkville, Victoria 3052 Australia; 2WMCResources Ltd., Kalgoorlie Nickel Smelter, P.O. Box 448,Kalgoorlie, WA 6430 Australia The use of Composite Furnace Module coolingsystems has been shown to give improved refractoryperformance in a number of above bath locationsin WMC flash furnaces. To test the behaviour of mod-ules in contact with a melt, a set of instrumentedmodules have been installed in the reaction shaft ofa nickel flash furnace. The location was chosen toprovide a suitably harsh environment to ensure rigor-ous testing, while still allowing relatively easy accessfor module installation. The modules were continu-ously monitored to provide information on the mod-ule performance, as well as the temperature in theshaft itself. The shaft temperature showed significanttransient behaviour, which resulted in heat fluxesthrough the modules ranging from 10 to 92 kW m-2.The modules were capable of handling the highestheat flux with no risk of the coolant boiling. This pa-per details the design and operation of the modulesover a period of seven weeks.

12:35 PMThe SKS Copper Smelting Process in China: Li Cheng1;Wang Jianming1; Wang Zhongshi1; Jiang Jimu1; HuangQixing1; 1Beijing Central Engineering and ResearchInstitute, ENFI, 12 Fuxing Ave., Beijing 100038 China The SKS copper smelting process was jointly devel-oped by Shuikoushan Mining Corporation and ENFI(Beijing Central Engineering and Research Institute forNon-ferrous Metallurgical Industries) in China. It is anew bath copper concentrate smelting process withoxygen enriched air. The pilot plant testwork was com-pleted successfully in 1993. SKS has demonstrated tobe an advanced bottom blown smelting process. Thistechnology got the First Class Prize of Scientific andTechnological Progress awarded by CNNC (ChinaNational Non-ferrous Metal Industry Corporation) in1994. The SKS process has significant capital and op-erating cost advantages. Its environmental and in-dustrial safety and hygiene performance represents

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a substantial improvement when compared to con-ventional technologies. The technology has gener-ated great interest in the Chinese metallurgical indus-try. Feasibility studies and basic designs have beencarried out to incorporate in retrofit and green fieldsmelter projects in China and abroad. This paperdescribes the history of the pilot plant operating data(50 tonnes dry feed/day), and discusses the featuresof the SKS technology, its application and possiblefuture trends.

Electrorefining: Refinery Operations II

Monday PM Room: IndigoOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: J. W. Holzenthaler, Phelps Dodge, ElPasso Works, El Paso, TX 79998 USA; P. E. Donaldson,Falconbridge, Kidd Creek Metallurgical Division,Timmins, Canada P4N 7K1

2:00 PMThe Red Metal of Amarillo: R. M. Donovan1; W. D.Read1; G. A. Herring1; H. E. Tallert1; 1ASARCO, Inc.,Amarillo Copper Refinery, P.O. Box 30200, Amarillo,TX 79120 USA This paper documents the efforts to improve qual-ity and production at the Amarillo Copper Refinery.It summarizes the change in attitudes, work proce-dures, equipment maintenance, instrumentation andthe ever changing market. The Amarillo Copper Re-finery is dedicated to the ASARCO Management Sys-tem, ISO-9002 and continuous improvement.

2:25 PMRecent Experiences at the Ventanas Electrolytic Re-finery: R. Abel F.1; N. Cornejo R.1; E. Correa C.1;1Fundición y Refinería Ventanas - ENAMI, Carretera F-30, N° 58270 Ventanas, Comuna Puchuncavi, V Re-gión, Chile In 1997, Ventanas electrolytic refinery expanded itsproduction capacity from 215,000 to 325,000 metrictons per year. This increase in capacity has involvedthe treatment of anodes with different impurity con-tents, changing the operational strategy of the plant.On the other hand, the increasing necessity to ac-complish environment conservation rules and qualityassuring requirements, has led the plant operation andadministration to compete in an advantageous way.The present work describes the results obtained in thestartup and in the operation of the ENAMI Ventanaselectrolytic refinery expansion, and shows the diffi-culties which have been faced in the processing ofanodes of increasing complexity, in a competitivemarket and with environment and quality restrictions.

2:50 PMModernization of the CCR Refinery: J. Y. Aubut1; C.Bélanger1; R. Duhamel1; Y. Fiset1; M. Guilbert1; N.Leclerc1; O. Pogacnik1; 1Noranda, Inc., CCR Refin-ery, 220 Ave. Durocher, Montreal-East, Québec,Canada H1B 5H6 The modernization of the CCR Refinery to perma-nent cathode technology is presently underway. The

360,000 mt/y refinery is being retrofitted to accept theKidd process. Part of this modernization includes theinstallation of Kidd stripping machines, and the totalreplacement of the materials handling equipment. Italso involves the reinforcement of building structuresto accept the new equipment and the ability to op-erate in different modes. The future equipment willinterface with some existing apparatus, which is be-ing retained for future operations. The whole opera-tion will be automated and will allow product trace-ability for quality purposes. This retrofit poses impor-tant challenges given the size and scope of the mod-ernization project and because it is being undertakenconcurrently with normal plant operations.

3:15 PMCopper Refinery Modernization: Project OrganizationCoping with a Multi-Constraints Context: P. C.Guillaume1; F. Michaud1; 1UM Engineering, 4, rue duBosquet, Louvain-la-Neuve 1348 Belgium Global plant modernization or expansions cannotbe considered in the same light as any other indus-trial investment project. Relationship between thepartners, relationships and communications with theclient, structure and organisation of the teamwork,schedule of the work, and a lot of other tasks andmissions devoted to external contractors, have to bedefined considering one fundamental input: an op-erating plant. For an engineering company, expertin processing, like UM Engineering, such a contextrequires a specific approach as well as specific pro-cedures able to efficiently challenge the generatedconstraints. First of all, even if a detailed audit hadbeen conducted at the beginning of the conceptualengineering phase, new elements will be discoveredduring the preparation and realization of the project,and must be continuously integrated. Consequently,a close proximity to the site is necessary. This is onereason why UM Engineering, most often, works inpartnership with a local engineering company. Thesecond important point for the client is that the op-eration must not be interrupted during the realization.In order to make that possible, UM Engineering hasdefined a specific project structure and organisation,integrating on a permanent basis, the operators (the“users”) in the project teams. This paper presents theway UM Engineering copes with this type of “multi-constraints” context with reference to the recent cop-per cellhouse modernization under realization for CCRRefinery of Noranda, Inc. in Canada.

3:40 PM Break

4:10 PMImprovements in the Tankhouse of the TamanoSmelter: M. Hashiuchi1; K. Noda1; M. Furuta1; K. Haiki1;1Hibi Kyodo Smelting Company, Ltd., Tamano Smelter,No. 6-1-1 Hibi, Tamano City, Okayama Prefecture,Japan In 1972, the tankhouse of the Tamano Smelteradopted a high current density electrolysis operationapplying the PRC (Periodic Reverse Current) method.In 1994, the phase four production expansion project,which incorporated significant re-structuring of theorganization, was completed and we have achievedan annual production capacity of 191,000 tons. Thetarget of this project, the production capacity, wasincreased by 18% and labor productivity by 25%. Af-

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ter the expansion, some improvements in the startingsheet section and the verticality of the electrodes werecarried out, and the efficiency of the operation wasgreatly enhanced, including the improvement of thequality of the electrolytic copper.

4:35 PMTankhouse Expansion and Modernization of CopperRefineries, Ltd., Townsville, Australia: B. O’Rourke1;1Copper Refineries Pty, Ltd., P.O. Box 5484, Townsville,Queensland 4810 Australia Copper Refineries Ltd. (CRL), Townsville is Australia’slargest producer and exporter of refined copper cath-ode. This status has been maintained by the imple-mentation of a significant capital works program thatincreased the production capacity to 270,000 t/y byJune, 1999. In 1979, CRL was the first in the world tocommission the ISA Process Technology which hasnow been marketed to 47 licensees worldwide. Thenew tankhouse design has focused particular atten-tion on customer requirements, operational improve-ments, materials handling and equipment modernisa-tion. Equipment which has been upgraded includescranes, anode preparation, cathode stripping andscrap washing machines along with the total replace-ment of the electrolyte and electrical reticulation sys-tems. Side stream electrolyte filtration has been intro-duced. Improvements to electrode alignment af-forded by the conversion to polymer concrete cells,precise electrode location, and the upgrade of theelectrode handling machines will ensure that CRLcontinues to be one of the world’s major quality cop-per cathode producers.

5:00 PMOutokumpu Moves Forward Towards Full Control andAutomation of All Aspects of Copper Refining: H.Virtanen1; T. Martti la2; R. Pariani3; 1OutokumpuHarjavalta Metals Oy, Kuparitie 5, Pori 28100 Finland;2Outokumpu Wenmec Oy, Riihitontuntie 7 E, Espoo02200 Finland; 3Outokumpu Technology, Inc., 351Thornton Rd., Lithia Springs, GA 30122 USA Outokumpu copper refining operations have along history of expansions and application of newtechnologies. Outokumpu is a name known aroundthe world for technological excellence in the field ofbase metals, and part of the policy of operations iscontinuous investment and investigation in new tech-nologies. The results of this hard work sometimes areimmediate and sometimes take years. The work doneduring the last years at the Outokumpu HarjavaltaMetals copper refinery, together with a sister technol-ogy group Outokumpu Wenmec, has started to bearfruit in terms of the following radical developmentsand advances that are and will be applied to assureOutokumpu's position as the technology leader anda low cost and safe producer. Some of the develop-ments discussed include the new anode and cath-ode design, mechanised electrode handling, celldesign incorporating features facilitating full automa-tion, automated short circuit detection and removal,automated on line anode slime removal, and highefficiency and intensity refining.

Hydrometallurgy: Design, Simulation andControl

Monday PM Room: HopiOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: Jackson Jenkins, Cyprus SierritaCorporation, Green Valley, AZ 85622-0527 USA;Mark F. Vancas, Bateman Engineering, Inc., Tuscon,AZ 85719 USA

2:00 PMNICO, A Dynamic Simulator for Leach-SX-EW Plants:Cristián Araya L.1; 1Kvaerner E&C, Dept. of Tech.,Nueva Tajamar, Las Condes 481 P19, Santiago, Chile A dynamic agglomeration, heap leaching, solventextraction and electrowinning software, called NICO,has been developed in order to either design or simu-late copper ore recovery plants. NICO contains a li-brary of routines, each representing a unit operationor piece of equipment, which are assembled like ameccano to match almost any wet plant configura-tion. Routines include agglomeration or curing eitherin drams or belts, belt conveyors, heap stacking andreclaiming, heap leaching of oxide, sulfide or mixedcopper ores, heap irrigation, drainage, ponds, mixer-settlers, filters, columns, coalescers, tanks, electrowin-ning cells, pumps, and all connections and relatedpiping. All models are semi-phenomenological, i.e.,they include all physical-chemical, mass, thermal,transport equations, which are required to representas closely as possible the equipment or unit opera-tion. However, operating experience has been incor-porated into the model in order to make it simpler,faster and reliable. This experience has been testedin several plants in Chile since 1992. Site meteorologi-cal data is simulated also; in this way the model isresponsive to weather conditions (temperature, solarradiation, ambient humidity, atmospheric pressure,wind velocity, etc). NICO has been used recently fordesign and optimization studies in copper plants inChile like Radomiro Tomic, Collahuasi and Zaldivar.A user-friendly interface allows fast and comprehen-sive simulations. The entire plant is shown in a singlegraphic screen, so the user can see all the relevantinformation, and soft-keys are provided in order tochange parameters on-line and watch their effect infinal copper production in cathodes. Model alsocalculates and reports operating parameters, as wellas estimated investments and operating costs.

2:25 PMModeling the Speciation of Sulfuric Acid - Cupric Sul-fate Solutions: J. M. Casas1; F. Alvarez1; G.Crisostomo2; G. Cifuentes3; L. Cifuentes2; 1Universidadde Chile, Depto. Ingenieria Quimica, Beauchef 861,Santiago, Chile; 2Univesidad de Chile, Dept. Ingen-ieria de Minas, Av. Tupper 2069, Santiago, Chile;3Universidad de Santiago, Depto Intenieria Metalúr-gica, Av.B. O’Higgins 3363, Santiago, Chile This work presents the development of an ionicequilibrium model and its use to simulate the distribu-tion and concentration of the species (speciation) in

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sulfuric acid-cupric sulfate solutions in the 0-2 pHrange, 0.1-10 gpI copper concentration range and15-45ϒC temperature range. The model consists of aset of equations which represent the equilibrium rela-tionships for the ionic reactions and the mass balancesfor the components present in the system. The effectof ionic strength was taken into account by correct-ing the equilibrium constant in concentrated solutions.Several species can be formed at different pH andtemperature values, the principal being: HSO4-, SO4

2-,CuSO4(aq), Cu2+, and H+ in order of increasing solu-tion acidity. Simulations show that species concen-trations are highly dependent on pH. The sulfuric acidspeciates mainly as bisulfate ion (HSO4-) and hydro-gen ion (H+) at pH values lower than 1. The modelpresented in this work can be applied to evaluateand to analyze the solution composition in electro-lytic copper processes such as electrowinning,electroreflnning, electrodialysis, and in the purifica-tion of various industrial solutions.

2:50 PMThe Use of a Mineralogical Data Base for ProductionForecasting and Troubleshooting in Copper LeachOperations: Wolfgang Baum1; 1Pittsburgh Mineral &Environmental Technology, Inc., 700 Fifth Ave., NewBrighton, PA 15066-1837 USA Copper and gangue mineralogy constitute themost critical parameters for the hydrometallurgicalprocessing and cost-efficient extraction of copper.Minor changes in copper, rock, or alteration mineral-ogy can severely impact the comminution efficiency,curing, agglomeration, acid consumption, copperextraction and PLS impurity loading. Further, copperleach operations, particularly in the southwesternUnited States, are increasingly challenged by a com-bination of low grades and semi-refractory copper.This paper discusses the metallurgical and economi-cal benefits of continuous mineralogical analyses inorder to establish and operate a mineralogical database in copper leach operations. Troubleshooting forcopper extraction, integration of process mineralogyinto production forecasting, and process optimiza-tion will be illustrated with operational experiencesfrom Chile and the United States.

3:15 PMA Framework for Improving the Ability to Understandand Predict the Performance of Heap Leach Piles: M.O’ Kane1; S. L. Barbour2; M. D. Haug3; 1O’Kane Con-sultants, Inc., 232-111 Research Dr., Saskatoon,Saskatchewan, Canada S7N 3R2; 2University ofSaskatchewan, Dept. of Civil Eng., 57 Campus Dr.,Saskatoon, Saskatchewan, Canada S7N 5A9; 3M. D.Haug and Associates Limited, 232-111 Research Dr.,Saskatoon, Saskatchewan, Canada S7N 3R2 Operators and designers require a comprehensivemodel to predict performance of heap leach pilesand provide input of reliable and defensible data foreconomic modeling. A conceptual, theoretical, ornumerical predictive model addressing the requiredmetallurgical, geological, biological, and opera-tional considerations should be developed within theframework of the hydraulic performance of the heapleach pile. It is generally agreed that segregation,compaction, and consolidation are physical aspectswhich significantly affect recovery and in general hy-draulic performance. Hydraulic performance of heap

leach piles can be described through the applica-tion of unsaturated zone hydrology. Unsaturatedzone hydrology describes the flow and storage ofmoisture and oxygen in a porous medium under con-ditions where the pore water pressure is less than at-mospheric. The porous material is “unsaturated” if anair phase, in addition to the water phase and solidmaterial phase, is present. These conditions describethe operation of a copper heap leach pile. This pa-per will focus on developing an understanding ofhydraulic performance in segregated heap leachmaterial and demonstrating that unsaturated zonehydrology can be used as the framework to improveunderstanding and prediction of heap leach perfor-mance.

3:40 PM Break

4:10 PMLarge Scale Hydrometallurgical Test Facilities of PhelpsDodge Mining Company: Kevin L. Purdy1; Robert E.Johnson1; 1Phelps Dodge Mining Company, ProcessTech. Ctr., 9780 E. Sanchez Rd., Safford, AZ 85546 USA The Process Technology Center of Phelps DodgeMining Company (PDMC) operates several test fa-cilities in support of PDMC’s hydrometallurgical op-erations. Installations for small leach columns, 15 cm.to 60 cm. (6 in. to 24 in.) in diameter, and large leachcolumns, 1.8 m. (6 ft.) in diameter, are complementedby a test facility for SX/EW operations. The history ofand reasons for the development of these facilitiesare described and original standard equipment isdiscussed. A primary goal in constructing these facili-ties was achieving a high degree of flexibility to al-low for testing of new equipment and new leachingand SX/EW technologies as they are developed.Along with this challenge, construction of a fully inte-grated SX/EW test facility on a small scale brought itsown set of challenges.

4:35 PMDesigning the Leach System for Cerro Negro Ore: A.F. Kaczmarek1; Joe Campbell3; W. J. Schlitt2; JosephM. Keane4; 1Cyprus Amax Engineering & Project De-velopment Company, P.O. Box 4444, Claypool, AZUSA; 2Kvaerner Metals, Metals E & C Div., 12657 AlcostaBlvd., Suite 200, San Ramon, CA 94583 USA; 3SociedadMinera Cerro Verde S.A., Asiento Minera Cerro Verde-Uchumayo, Casilla, Arequipa 299 Peru; 4KD Engineer-ing Company, Inc., 7701 N. Business Park Dr., Tuscon,AZ 85743 USA Cerro Negro is an undeveloped ore body locatedat the Cerro Verde mine near Arequipa, Peru. Theminable reserve contains 70 Mt of oxide ore grading0.532% copper. Mineralization is hosted in three dis-tinct rock types: tourmaline breccia, crackle brecciaand granodiorite. Rock type effects copper recoveryand acid consumption. The paper describes Cyprus'testwork philosophy and the resulting four-phasemetallurgical program used to define the commer-cial leaching parameters. Copper recovery and acidconsumption were monitored as functions of crushsize, heap height, irrigation rate and acidulation con-ditions. Single lift, on-off and permanent multi-lift heapswere considered. Leach cycle times were based onincremental copper extraction and acid consump-tion rates, with added constraints imposed by opera-tional requirements. The optimum leach system in-

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volves an on-off pad using tertiary crushed ore acidu-lated with 20 kg/t acid and stacked to a height of 6.5m. The active leach cycle is 82 days at an irrigationrate of 0.26 l/min/m2. Under these conditions copperrecovery is expected to average 81% over the life ofthe mine.

5:00 PMInterpretation of the Recovery/Time Curve and Scale-Up from Column Leach Tests on a Mixed Oxide/Sul-fide Copper Ore: Ronald J. Román1; Jose HectorFigueroa P.2; Jorge Enrique Ruiz H.2; Jorge Helleon G.3;Efrén Pérez S.4; 1Leach, Inc., 4741 N. Placita del Sol,Tucson, AZ 85749 USA; 2Mexicana de Cananea S.A.de C.V., Av. Juarez S/N, Cananea, Sonora 84620Mexico; 3Mexicana de Cobre, S.A. de C.V., Aptdo20, Nacozari, Sonora 84340 Mexico; 4University ofSonora, Dept. of Geology, Hermosillo, Sonora 83000Mexico The shrinking core model for coarse particle leach-ing has been generally accepted as describing theleaching of a copper oxide or sulfide ore. However,when a mixed oxide/sulfide ore is leached this modelcan not be used in its simple form because at leasttwo and possibly three separate leaching processesare occurring simultaneously (dissolution of oxide cop-per minerals, secondary copper minerals and prima-rily copper minerals). It has been impossible to iso-late their individual leaching curves from the recov-ery/time curve generated by the column leach test.This paper describes a test program carried out atthe Groupo Mexico, Mexicana de Cobre’s La Caridadoperation in which the individual recovery/time curvesfor the leaching of copper oxide mineral, secondarycopper mineral and primary copper minerals weredeveloped from standard column leach tests. Oncethe individual recovery/time curves were developedscale-up of the column leach test results to the com-mercial heap leaching operation is possible by usingthe shrinking core model.

5:25 PMSimulation of Oxidized Copper Ores Heap Leaching:Luiz R. P. De Andrade Lima1; 1Federal University ofBahia, Polytechnic School, Rua Aristides Novis, 2, Sal-vador, Bahia 40210-630 Brazil This paper presents a mathematical model for theoxide copper ore heap leaching process. The dataused in the model include physical-chemical, geo-metrical and operational data, as: leachable metalsore contents, flow rate and acid concentration, pa-rameters of passivity, ore size distribution, the aver-age residence time of the solution in the heap, height,irrigated area and weight of ore in the heap. In thismodel the heap is divided into horizontal and planelayers of constant area. The flow of the liquid in theheap is considered unidirectional and the solid-fluidreaction model is considered under diffusive control.The average residence time of the solution into theheap and the apparent effective diffusivity of the acidthrough the ore particles have a significant influenceon the rate of the copper extraction and its concen-tration in the pregnant solution; therefore these pa-rameters are used in the model calibration. When thisalgorithm was applied to a laboratory test, the re-sults showed that the model is adequate to predictthe process performance.

5:50 PMPyrite as a Stockpile Leach-Aid: John L. Uhrie1;1Phelps Dodge Mining Company, Process Tech. Ctr.,9780 E. Sanchez Rd., Safford, AZ 85546 USA Oxide stockpile leaching operations can realizeincreased copper recovery and decreased acid con-sumption from in-situ generated acid resulting fromthe oxidation of intentionally introduced pyrite recov-ered from mill tailings or other sources. While all ox-ide leach ores can benefit from pyrite addition, lowacid consuming ores can show remarkably increasedrecovery and net acid generation; however, morehighly acid consuming ores will show benefit moreexclusively through increased copper recovery. Ad-ditional work shows that the value of highly acid con-suming ores can be optimized by balancing copperrecovery against acid consumption.

Hydrometallurgy: Concentrate Leaching

Monday PM Room: Apache/BisbeeOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: V. I. Lakshmanan, Ortech Corpora-tion, Mississauga, Ontario,Canada L5K 1B3K; BrentHiskey, University of Arizona, Tucson, AZ 85721 USA

2:00 PMAmmonia Leaching of Copper Sulfide Concentrates:Nathaniel Arbiter1; Terry McNulty2; 1Columbia Univer-sity, Emeritus Professor, Henry Krumb School of Mines,6300 S. High Valley Rd., Vail, AZ 85641 USA; 2T.P.McNulty and Associates, Inc., 4550 N. Territory Place,Tucson, AZ 85750 USA The first ammonia leaching plants, applied to cop-per carbonate and native copper tailings in 1915, werefollowed more recently by research and developmentof flowsheets for ammonia leaching of sulfide con-centrates. These were applied to two commercialplants. Anaconda’s Arbiter Plant started up in 1974with a design capacity of 36,000 tons/year of cath-odes, to be produced by ammonia leaching withoxygen, followed by solvent extraction and electrow-inning. The plant shutdown in late 1977 as a result ofhigh maintenance and operating costs, partly dueto harsh winters; to complications associated withsulfate disposal; and to changes in mineralogy. BHP’sColoso plant in Chile was designed to produce 80,000tons/year of cathodes by leaching part of Escondida’sconcentrate production. Using a similar flowsheet butwith air and low temperatures to avoid sulfate pro-duction, it started up in late 1994 and shutdown inmid 1998 after failing to reach cathode design ca-pacity, and experiencing problems with its technol-ogy. The paper reviews the technologies and alsoalternative methods for overcoming the problems.

2:25 PMAn Electrochemical and Chemical Study of theLeaching of Copper Sulfides in Acidified Ferrous Sul-fate Solutions Sparged with an O2-SO2 Mixture:Michael James Perpich1; Paul Duby1; 1ECI Technol-ogy, 1 Madison St., East Rutherford, NJ 07073 USA

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Electrochemical and chemical leaching tests werecarried out on chalcocite, covellite and chalcopy-rite in acidified iron sulfate solutions sparged with amixture of O2 - SO2. The gas mixture catalyzed the fer-rous to ferric oxidation reaction in situ and, therefore,increased the redox potential and oxidizing strengthof the solution. Anodic polarization curves in dilutesulfuric acid on copper sulfide electrodes showed thatchalcopyrite passivates and dissolves at current den-sities orders of magnitude less than chalcocite andcovellite. The addition of a depassivating agent (Ag+)increased the passive current density of chalcopyriteand caused breakdown near 0.625 V (SCE). Thedepassivating effect was also observed during theleaching of chalcopyrite particulate samples as smallamounts of Ag+ added to acidified iron sulfate solu-tions in the presence of O2 - SO2 mixtures greatly in-creased the leaching rate and the total amount ofCu oxidized (>90%). Passivation was prevented in theabsence of Ag+ by decreasing the initial oxidizingpower of the solution and by pretreating the samplein a reductive leach. Both of these methods resultedin transformation of the chalcopyrite surface from itscharacteristic greenish-gold into deep black. In-creased concentrations of Fe+++ due to O2 - SO2sparging were then able to oxidize the transforma-tion product.

2:50 PMFerrous Promoted Chalcopyrite Leaching: NaokiHiroyoshi1; Hajime Miki1; Tsuyoshi Hirajima1; MasamiTsunekawa1; 1Hokkaido University, Grad. Schl. ofEngr., Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628 Japan It is generally accepted that ferric ions are effec-tive for leaching chalcopyrite as an oxidant and fer-rous ions contribute to the leaching only as a sourceof the oxidant ferric ions. However, this paper showsthat ferrous ions are more useful for leaching chal-copyrite than oxidant ferric ions in sulfuric acid solu-tions in air at ambient temperatures. Leaching experi-ments and dissolved oxygen consumption measure-ments were carried out with a very pure chalcopyriteand 0.001 - 1 mol dm-3 sulfuric acid solutions contain-ing 0 - 0.1 mol dm-3 ferric or ferrous ions at 303 K. Chal-copyrite oxidation with dissolved oxygen was pro-moted by ferrous ions but suppressed by ferric ions.As a result, the amount of extracted copper was largerwith ferrous ions than with ferric ions. Effects ofThiobacillus ferrooxidans on the ferrous promotedchalcopyrite leaching were also investigated anddiscussed based on the experimental data.

3:15 PMOpen

3:40 PM Break

4:10 PMEngineered Membrane Separation (EMS) Systemsfor Acid Hydrometallurgical Solution Concentration,Separation, and Treatment: Ron Bernard1; Dennis H.Green1; Jeffrey J. Mueller1; 1HW Process Technologies,Inc., 1208 Quail St., Lakewood, CO 80215 USA HW Process Technologies has successfully devel-oped and commercialized various applications uti-lizing Engineered Membrane Separation (EMS) sys-tems for the processing of acidic copper hydromet-allurgical solutions and wastewaters. Copper hydro-

metallurgical EMS applications include water bal-ance control and increased copper concentrationin heap and dump copper leach operations,tankhouse bleed stream treatment to separate/re-cover copper and cobalt from iron, and removal ofPLS/Electrolyte suspended solids/colloids to eliminate“crud” formation during copper SX/EW. Similar appli-cations are under development to provide ionicseparations in copper refinery bleed streams, coppersmelter acid plant streams, as well as organic/LIX re-moval from aqueous electrolyte and raffinate streams.Copper mine wastewater EMS applications includetreatment of copper leach solution contaminatedgroundwaters for copper recovery and treatment ofunwanted heap/dump drainage to provide en-hanced precipitation, a smaller precipitation plant,improved operating costs and better quality dischargewater, particularly in terms of TDS and sulfates. A dis-cussion of the EMS technology and general sepa-ration results on typical process solutions and waste-waters will be presented. HW Process Technologies,Inc. commercial installations treating copper preg-nant solutions and leach solution contaminatedgroundwaters are in-place at an old Asarco smelter/refining operation, Mexicana de Cananea coppermine, and a major U.S. copper mine, with severaladditional installations pending. Several case stud-ies, including results from a selection of these installa-tions, will be included with detailed capital, operat-ing cost, and system payback data.

4:35 PMAdvanced Cast Stainless Steels for Copper IndustryPumps: Arto K. Riihimaki1; 1Ahlstrom Pumps Corpo-ration, Karhula 48601 Finland The description deals with duplex stainless caststeels and austenitic high molybdenum steels used inpumps for severe condition service. The main mod-ern nitrogen alloyed duplex cast steels are presentedin the ASTM standard A-890. Two grades of high mo-lybdenum austenitic stainless steels there are pre-sented in ASTM A-744 (-96) standard i.e. CN-3MN andCK-3MCuN. The latest and most corrosion-resistantstainless steel grade is AVESTA 654 SMO. AvestaSheffield the trademark owner has granted AhlstromPumps license to produce the material. This new stain-less steel as pump material for severe service has im-proved properties in the hydrometallurgy andelectrorefining processes of metal and especially inthe copper industry compared to duplex stainlesssteels. The paper deals briefly with the foundry pro-cess to manufacture high alloy stainless steel pumpcastings. The AOD-method (AOD= Argon Oxygen De-carburization) is an important prerequisite for the melt-ing of low carbon, high chromium and molybdenumalloyed nitrogen steels. The properties of these steelsare included. The main topic is the corrosion resis-tance of the above-mentioned pump materials insevere service. Results of short-time erosion and cor-rosion tests are discussed and compared with the re-sults of plant tests. Practical results of pump materialsperformance in severe service for the copper indus-try are given. The new high alloyed cast stainless steel(main elements: Cr~24%, Ni~22%, Mo~7,3% andN~0,5%) has shown improved corrosion and erosionproperties as process pump material in several severeservice applications e.g. in the metal industry.

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5:00 PMMine Site Production of Value Added SX-EW CopperProducts - The Alternative to Cathode: Stephen J.Kohut1; John J. Pio1; Mark D. Precup1; 1ElectroCop-per™ Products Limited, 1255 W. Baseline Rd., Suite 288,Mesa, AZ 85202 USA Until recently SX-EW technology has only been usedto produce conventional cathode for the cyclicalcommodity marketplace. Unlike electrorefining, SX-EW lends itself to the integration with the downstreammanufacturing technologies for direct mine site pro-duction of value added products. The integration ofSX-EW and downstream manufacturing results in theelimination of redundant process steps, the cost sav-ings, and the access to value added product mar-kets which can buffer the producer from swings inthe cathode market. SX-EW production of copperpowder and powder-based products has been dem-onstrated at the pilot plant level. The SX-EW processhas been successfully redesigned to meet the morespecific demands of engineered products. Challengesinclude the solution purity, the cell ventilation, the highcurrent density operation and the product handling.Successful demonstration of mine site production ofvalue added SXEW products opens up new non-com-modity marketplaces to the mining industry.

5:25 PMCopper Production from Leaching Solutions with anInnovative Process Competitive to Traditional SolventExtraction - Electrowinning: M. Olper1; M. Maccagni1;C. J. N. Buisman2; C. E. Schultz2; 1Engitec s.r.l., viaBorsellino e Falcone 31, Novate Milanese, Milano20026 Italy; 2Paques Bio Systems B.V., P.O. Box 52, Balk8560 AB The Netherlands Today, copper production form direct leaching ofoxidized copper ores followed by solvent extraction-electrowinning (SX-EW) accounts for about 15% of thetotal primary world output. SX-EW is well-acceptedprocess with an operating cost in the range 16-20cents/lb. copper for small and medium size plants,depending on the plant size and local conditions.However, this technology presents some drawbacksthat affect the operating cost and cause environmen-tal concerns. ENGITEC and Paques Bio Systems havedeveloped a new process that avoids the solvent ex-traction step and operates the copper electrowinningstep at a lower cell voltage because of the depassiva-tion of the anodic reaction. The consequence of thisnew concept is that the direct operating cost is in therange 10-12 cents/lb of copper. This new process iscomposed by the following steps: Selective precipi-tation of copper from leach solutions by biogenicH2S, yielding CuS and regenerating acid. Leachingof the CuS with a ferric fluoborate solution to dissolvecopper and produce elemental sulphur that is re-cycled back to the H2S biogeneration step. Electrow-inning of copper fluoborate solution in a diaphragmcell with the ECUPREX Process, producing coppercathodes and regenerating the ferric fluoborate so-lution to be recycled back to the leaching step.Biogeneration of H2S from the elemental sulphur gen-erated during the leaching step, with the nutrientsource for the anaerobic bacteria selected from awide range of organic substances and/or some in-dustrial by-products containing carbon and hydro-gen. The paper describes all process steps with par-ticular reference to the biological H2 generation tech-

nology. Also discussed is the capability of theECUPREX Process to treat copper sulfide concen-trates and copper matte.

5:50 PMA Look at Leach SX-EW with 2020 Vision: Sharon K.Young1; 1Versitech, Inc., 1438 W. San Lucas Dr., Tuc-son, AZ 85704 USA What might an ideal leach-to-cathode/productsystem look like in the next century? The paper looksat the synergies of the 60’s and 70’s that led to thehighly effective copper leach SX-EW system of the 90’s.Standing in the year 2020 focuses on what break-through technologies might make possible a next-generation leach/extraction/metal recovery system.Many of the pieces of such a technology have beendeveloped, even piloted: in situ leaching, enhancedbioleaching, heap leaching of fine particles, resin inpulp, ion exchange, alternate anode reaction elec-trowinning, novel anode coatings. With nearly non-existent research on the part of individual large com-panies, the greatest challenge may not be inventingthe technologies but rather inventing an industry “will-to-create.”

Mineral Processing: Metallurgy

Monday PM Room: JeromeOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: H. J. D. Galaviz, Great WesternChemical; J. Menacho

2:00 PMAn Empirical Equation for the Recovery - EnrichmentRatio Curve (AREV Model): Marco A. Vera1; J-P.Franzidis1; E. V. Manlapig1; 1The University of Queensl-and, Julius Kruttschnitt Mineral Rsch. Ctr., Isles Rd.,Indooroopilly, Brisbane QLD 4068 Australia This paper proposes a simple two-parameter modelfor the typical inverse relationship between recoveryand flotation concentrate grade. The model is basedon the mineralogical limitations, imposed by the ma-terial properties. One parameter (R*) describes theproportion of metal content which is floatable, andthe other (b) is the rate at which the fastest floatingparticles are being contaminated by the other lessvaluable particles present in the mineral system. Onesignificant feature of the recovery-grade curve is thatinitial recovery (i. e. R —> 0) is at the purest attain-able mineral grade, but as recovery rises the cumula-tive grade of the concentrate tends to the feed grade.The ideal recovery-grade curve for a particular min-eralogical system can be obtained by release analy-sis: the release analysis curve determines the maxi-mum or limiting separation efficiency. The model pro-posed in this work is similar to the linear recovery—cut-off grade model of Dell (1), but has the advan-tage of describing the whole curve.

2:25 PMDevelopment of an “On-line” Eh-pH ElectrochemicalSensor for the Flotation Process Control: Christian C.Hecker1; Juanita Ramirez1; Ernesto B. Beas2; Fernando

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M. Cartes2; 1Universidad de Concepción, Dept. deIngenieria Metalúrgica, Edmundo Larenas 270, Casilla,Concepción 53-C Chile; 2Codelco-Chile, El TenienteDiv., UGA - MINCO, Millan, Rancagua 1040 Chile An Eh-pH electrochemical sensor developed for on-line pH and redox potentials copper sulfide flotationprocess control was studied. The electrochemical sen-sor ceU includes two metallic platinum electrodes, ametaffic antimony electrode and a high impedancereference cell, which are polarized with a potentio-stat. For pH and redox potential determinations, theSb and platinum electrode potentials are measured,respectively, against the polarized electrochemicalreference system. The behaviour of this electrodeconfiguration has been investigated in a laboratoryscale. An electrochemical sensor device has beensuccessfully installed and checked in El Teninte Co-lon Concentrator’s SAG line feeding the copper flo-tation rougher circuit.

2:50 PMEffect of Clay Slimes on Copper, Molybdenum Flota-tion from Porphyry Ores: S. Bulatovic1; D. M. Wyslouzil1;C. Kant1; 1Lakefield Research Limited, 185 Conces-sion St., Postal Bag 4300, Lakefield, Ontario, CanadaK0L 2H0 The presence of clay adversely affects the float-ability of copper and molybdenum during process-ing porphyry copper/molybdenum ores. In addition,reagent consumptions are much higher than whentreating clay-free ores. Ores containing kaoline,brammollite, illite and montmorillonite were examinedin the laboratory to determine how clay minerals af-fect the floatability of copper and molybdenum, andto find a possible solution to alleviate the harmful ef-fect of clay slimes. It was demonstrated that the pres-ence of clay mostly affects floatability of coarse andmiddling particles, and reduces selectivity. The resultsof the research work showed that there may be sev-eral possible ways of reducing the detrimental affectsof clay slimes on flotation, some of which include a)use of alternative flowsheets, b) Rotation at reducedpulp density, and c) the use of special frotbers. Theapplicability of the findings in plant practice are dis-cussed.

3:15 PMTechnological Development for Igarape Bahia/Alemao Copper-Gold Project: Vânia L. L. Andrade1;Nilce Alves dos Santos1; Rinaldo Pedro Nardi1;1Companhia Vale do Rio Doce - CRVD, Rsch. Ctr., BR262 km 296, Santa Luzia, MG–Brazil Igarape Bahia Mine is located in Carajas area,northern Brazil. Currently Companhia Vale do RioDoce operates there a CIP/ heap leaching plant treat-ing an oxide gold ore containing about 4 g A /t and0,2% Cu, which produces 11 t of gold per year. Re-cent geological survey has identified a significantcopper-gold reserve underneath the oxide gold ore.The processing aspects of this copper-gold sulfide oreare described in this paper. It includes ore character-ization studies, grinding and flotation tests, orebodyvariability assessment, flowsheet selection and pre-liminary economical evaluation. Emphasis is given to

studies aimed at depressing fluorine bearing miner-als to achieve a clean and marketable flotation con-centrate.

3:40 PM Break

4:10 PMGold Occurrence in the Sar Cheshmeh Prophyry Cop-per Ore and Its Behaviour during Beneficiation:Mohammad Mehdi Salari Rad1; Masami Tsunekawa1;Tsuyoshi Hirajima1; Tetsuro Yoneda1; 1Hokkaido Uni-versity, Grad. Sch. of Engr. Min. Process. Lab., Kiat 13,Nishi 8, Sapporo, Hokkaido 060-8628 Japan An investigation of gold distribution in the mill prod-ucts of Sar Cheshmeh beneficiation plant demon-strates that on average 44% of the gold is routinelyrecovered as a by-product in the copper concen-trate, and the remaining is lost to the tailing. In orderto evaluate the causes of gold losses, the distributionand mode of gold occurrence in the Sar Cheshmehore and mill products were studied. Searching for goldwithin samples and within individual grains of sulfideminerals was carried out by SEM in the backscatteredelectron mode and SIMS, respectively. The mineral-ogical distribution of gold revealed by microbeamtechniques were combined with the results of relevantmetallurgical experiments including, sizing, heavy liq-uid separation, and diagnostic leaching tests, andthe nature and location of gold in the ore and millproducts were determined. The combined results ofthe experimental approaches pursued suggest thatwhile there are some gold in solid solution and/orcolloidal size within sulphides of the Sar Cheshmehores, “visible” gold is the principal form of gold oc-currence at Sar Cheshmeh.

4:35 PMLead Ions and Sphalerite Recovery in Copper RougherFlotation: C. Sui1; J. C. A. Grimmelt1; F. Rashchi1; R.Rao1; J. A. Finch1; 1McGill University, Dept. of Miningand Metall. Eng., 3610 University St., Wong Bldg.,Montreal, Québec, Canada H3A 2B2 A common objective in many Cu/Zn concentra-tors is to reduce the loss of Zn to the Cu-concentrate.One suspected source of the problem is accidentalactivation of sphalerite by heavy metal ions such aslead. One method of quantifying surface metal ionconcentration is extraction With ethyl-diamine-tetra-acetate (EDTA). This was used to survey Cu-rougherflotation at three Cu/Zn concentrators: Les MinesSelbaie, Falconbridge’s Kidd Creek division, andHudson Bay Mining and Smelting. Although all haveless than 0.2% galena in the ore, Pb ions proved anabundant extractable metal. From a laboratory studya model of surface coverage of lead species gener-ated by an ore was combined with an estimate ofsurface concentration of lead required to activatesphalerite to explore the possibility of accidental ac-tivation. Ores with Pb-grade as low as 0. 1% can pro-duce sufficient Pb to be a potential problem.

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Movement of Copper and Industrial Out-look: Markets and Trends

Monday PM Room: CopperOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: C. Twigge-Molecey, Hatch Associ-ates, Ltd., 2800 Speakman Dr., Mississauga, Ontario,Canada, L5K ZR7; Norbert L. Piret, Piret & StolbergPartners, Consulting Engineers, Duisburg D-47279Germany

2:00 PMGlobal Copper Consumption into the New Millennium:Gary A. Campbell1; 1Michigan Tech University, SBE,1400 Townsend Dr., Houghton, MI 49931 USA This article is an analysis of world consumption ofcopper for the years 1976-1996. It is done to providea comparison of what has happened over this timeperiod with the trends of previous years in order tolearn more about world copper consumption and toforecast world copper consumption trends into thenew millennium. The analysis begins by document-ing the geographic trends of consumption of cop-per for the years 1976-1996 by both region and keyindividual countries. Then, variables based on the in-tensity-of-use hypothesis and the intensity-of-use tech-nique are selected and tested against the observedconsumption behavior by using the correlation coef-ficient technique. The statistical results and their im-plications for the consumption of copper into the newmillennium are discussed.

2:25 PMThe Chilean Copper Smelter Management Way:Sergio Demetrio1; Miguel Ángel Durán2; RubenAlvarado3; Leonel Contreras4; Jorge Ahumada5; ErnestMast6; José Sanhueza7; Edmundo Morales8; 1ConOptiS.A., Cerro San Ramon 1491, Las Condes, Santiago,Chile; 2Chagres Smelter, Compañia MineraDisputada de Las Condes, Catemu, Chile; 3CaletonesSmelter, El Teniente Div., Codelco-Chile, Rancagua,Chile; 4Potrerillos Smelter, El Salvador Div., Codelco-Chile, Potrerillos, Chile; 5Chuquicamata Smelter,Chuquica-mata Div., Codelco-Chile, Calama, Chile;6Altonorte Smelter, Noranda Chile S.A., Antofagasta,Chile; 7Paipote Smelter, ENAMI, Copiapó, Chile;8Ventanas Smelter and Refinery, ENAMI Refinery,Quintero, Chile Over a period of nearly a hundred years through-out this century, the company direction and man-agement of copper smelters in Chile has evolved fromone characterized by a paternalistic, autocratic styleto one which empowers the local management teamand people for running the smelter as a successfulbusiness. This paper discusses the evolution of thepresent style of management amidst changes in theChilean Government, the mining industry and soci-ety since the beginning of this century.

2:50 PMThe Group of Experts on Minerals and Energy Devel-opment and its Role Regarding Copper MiningSustainability in the Asia-Pacific Region: Tomas

Astorga1; Raul F. Campusano1; 1GEMEED-APEC, Min-erals and Energy Exploration and Dev., Ministry ofMining, Teatinos 120, 9th Floor, Santiago, Chile APEC, the Asia Pacific Economic Cooperation isthe forum of 18 economies, having a combined GDPof approximately 56% of the total world income, andover 45% of global trade. Its mining sector producesa large portion of the main minerals and metals inthe world. In 1997, APEC economies produced 67%of world copper output, 55% of gold, and over 45%of other base metals. Mining in APEC captures morethan 60% of the total mining investment in the world.Against this background, the Expert Group on Miner-als and Energy Exploration and Development, in shortGEMEED, was created in 1996, under the auspices ofthe APEC Energy Working Group. The sustainable de-velopment of mining activities is a main concern inAPEC and GEMEED. Several programs related to thesubject are actively being pursued by the ExpertGroup. Among them, it should be noticed the cre-ation of an Environmental Cooperation Sub Groupcoordinated by Japan, whose main aim is to encour-age proposals related to the environmental sound-ness of mining projects in the region. Also, it shouldbe noted the existence of a Database Steering Com-mittee whose focus is the development of an infor-mation network related to mining opportunities in theregion. GEMEED is a gathering of experts from all theAPEC economies. As such, it represents a privilegedforum to discuss policy issues related to mining. Onthis regard, the paper focuses on concrete actionstaken by GEMEED to enhance the sustainability ofthe copper activity in the region.

3:15 PMThe 21st Century: A Century for the ChuquicamataMine: Juan H. C. Rojas1; 1Codelco Chile, DivisionChuquicamata, Chuquicamata, Chile The Chuquicamata mining and metallurgical com-plex is the main division belonging to CorporacionNacional del Cobre de Chile (Codelco-Chile) and itaccounts for 50% of the 1.4 Mt of fine copper outputof the Corporation. It has been producing coppersince 1915. The paper refers to the challenges thatChuquicamata has to solve in the near future. Thesechallenges are: the increasing operation costs asso-ciated to a 800 m depth pit with low prices in an over-stocked copper market; the increasing people’s sen-sitivity to environmental preservation; and, the trans-formation needed for achieving high levels of orga-nizational effectiveness. According to Corporatepolicy, Chuquicamata is making efforts to switch froma management style focused on supply to a man-agement style focused on demand side of the indus-try. In this direction, we attempted to establish strate-gic alliances to develop both new copper productsand uses, to rise the metal demand. In more than 80years of operation, Chuquicamata had exploited justone third of its geological resources. The exploitationof the remaining two third is a huge engineering chal-lenge, taking into account the depth of the deposit,the impurities content, the decreasing ore grades andthe transportation distances for waste dumping. Allof those factors are relevant in the economic processof transforming geological resources into ore reserves.Chuquicamata has other limitations. First, a 20,000people town just aside the pit that limits the mining

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rates because of dust generation; second the scarce-ness of water in the desert area where Chuquicamatadeposit is located; and, finally, the new tailing pondis a problem which solution will demand huge engi-neering efforts and investments. People are the prin-cipal factor associated to a company success. In thisfield, Chuquicamata has been progressing, but muchmore efforts from people will be necessary to reduceproduction costs for being successful as any otherprice-taker within the copper industry. Chuquicamatamust develop the skills of its Supervisors to transformthem into leaders and entrepreneurs, who addition-ally have the challenge of passing on their knowl-edge to non-professional workers. It is an ethic com-mitment to assure personal and professional growthof workers, as the only sustainable way to get realand integral success.

3:40 PM Break

4:10 PMChile’s Mining and the Application of the Basel Con-vention: G. E. Lagos1; 1Catholic University of Chile,Ctr. for Mining, Avda. Vicuña Mackenna 4860, Macul,Santiago, Chile This paper analyses the scope and instrumentsemployed by the Basel Convention for regulating thetransboundary movement of hazardous wastes, thepresent and projected hazardous waste regulationsof Chile, reviews the Chilean import/export trade ofwastes of the period 1985-1995, and discusses the in-fluence that the Basel Convention has had on min-ing trade, its perceived benefits and costs, and pos-sible effects on Chile’s trade of the application of theConvention’s Decision III/1. There is no quantitativeestimation as to the effect of the Convention on thegeneral volume of imported or exported materials des-tined for recovery, recycling, reclamation, or reuse.All recycling imports, with the possible exception ofresidues of petroleum oil, which occurred during thedecade 1985-1995, can be classified tentatively as nonhazardous. The entry into force of the Conventionhas had several effects on Chile’s trade. It has broughthome the need to have a comprehensive hazardouswaste legislation, it has been a base for applyingimport restrictions, which in all likelihood, would haveotherwise not been applied. The benefits and costsof this import restriction, as well as those of the multi-lateral export ban are analyzed.

4:35 PMCopper, Market Growth Potential and Threats in theAsia Pacific Region: Thomas Astorga1; Raul F.Campusano1; 1GEMEED-APEC, Dept. of Mining,Teatinos 120, 9th Floor, Santiago, Chile APEC, the Asia Pacific Economic Cooperation isthe forum of 21 countries having approximately 56%of the total world income, and over 45% of globaltrade. In 1997, APEC economies produced 67% of theworld copper output, 55% of gold, and over 45% ofother base metals. Mining in APEC captures more than60% of the total mining investment in the world. Newand emerging economies are now appearing in thedemand scenery, such as China. New trends in theinternational environmental regulations are posingquestions related to the use of copper in different in-dustrial and consumption applications. These mayhave a strong impact on future trade of copper. New

applications are also appearing based in new tech-nology fields. The paper examines the growth poten-tial of the copper market in main consumer and highlypopulated economies of APEC, incorporating analy-sis of various interrelated factors. It also analyses theoutlook of the copper supply. Its conclusions point tothe need to implement demand outlook models. Fi-nance and economic reforms will open importantavenues for trade growth in basic metals, particularlycopper. Changes in the consumption patterns ofhighly populated countries will add to better perspec-tives of copper demands. The recovery of a fast paceof economic growth in the APEC region will bringnew demands for copper, especially as a conse-quence of high tech applications. More extendedpolicies focused in the need for developing energyefficiency programs and schemes will add to this pic-ture.

5:00 PMTrends and Insights into Worldwide Copper Acquisi-tion Activity: Douglas B. Silver1; 1Balfour Holdings,Inc., 10 Inverness Dr. East, Suite 104, Englewood, CO80112 USA Of all the base and precious metals, copper con-tinues to receive the greatest amount of investment.Worldwide copper acquisition activity has increasedduring the past half decade because of multiplegovernment privatization programs, the opening ofCentral African markets and the dismantling of Com-munism. Examining the large number of transactionsalso provides insights into negotiating techniques asthey relate to local business cultures, the probableflow of future capital and development activities andthe dynamics of foreign investment. This presentationwill also provide quantitative statistics of these issues.It will summarize the terms of these recent copper re-source transactions, assess their significance from atechnical and geographic perspective and provideinsights about the future of copper exploration, de-velopment and mining.

Pyrometallurgy-Operations: Session II

Monday PM Room: EstrellaOctober 11, 1999 Location: Pointe Hilton Resort

Session Chair: Phil Mackey, Noranda TechnologyCentre, Pointe Claire, Québec, Canada; N.Santander, U. de Chile and U. Mayor, Dept. ofMetallu. Eng., Santiago, Chile

2:00 PMCopper Smelter Waste Heat Boiler Technology for theNext Millennium: Rauno Peippo1; Hannu Holopainen1;Jari Nokelainen1; 1Foster Wheeler Energia Oy,Relanderinkatu 2, Varkaus FIN-78200 Finland Horizontal Waste Heat Boiler (WHB), today’s provenand dominating technology for copper smelter gascooling, has been utilized by the industry for over halfa century. During this time development has takenplace in geometry, flow characteristics, cleaning tech-nology and design details. This development hasbeen driven by improved understanding of the spe-

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cific process requirements, gained both by wide ex-perience and by utilizing new emerging design tools,like computer flow modeling. It had to wait till mid90’s to unite effective and proven Spring Hammercleaning technology and the process benefits gainedby gas guiding vanes or baffle wall in the coppersmelter WHB design. The new design has demon-strated improvement in gas cooling efficiency andthe process conditions down stream in form of lessdust sticking problems in the boiler and precipitators.Reduced weak acid production has also been re-ported as a result of the design. The theoretical as-pects, computer flow modeling results and actualbenefits measured in old smelting line modernizationare discussed. Experience from modernization projectssuch as Phelps Dodge, Atlantic Copper, Mexicanade Cobre, and Nippon Mining, Saganoseki, are dis-cussed. In mechanical design there has been devel-opment resulting improved gas tightness with lesscorrosion and better control of dust sulfation. An es-sential improvement is the integration of the boilerhopper and dust removing conveyor. Having no steelplate casings in the hopper and conveyor sectionbut using of boiler tube membrane instead eliminatesthermal expansion differences. The dust conveyor willbe effectively cooled against hot dust lumps fallingdown while the acid dew point corrosion is preventedin the cooler sections of the hopper. Conceptual fea-tures are presented of a new generation Copper FlashSmelter WHB presently under construction at BolidenMineral, Skelleftehamn, Sweden, where the latest de-velopment and innovations are adopted.

2:25 PMTons and Profit from Understanding Gas Cooling andHeat Recovery: Kurt A. M. Westerlund1; Olaf Piehl1;Wolfgang Abeck1; 1Oschatz GambH, Dept. of Non-Ferrous Gas Hand. & Heat Recovery, Westendhof 10-12, Postfach 102843, Essen D-45028 Germany The basic function of primary gas handling down-stream non-ferrous pyrometallurgical processes iscooling hot sticky gases to treatable temperature lev-els (e.g. entering ESP). That means managing efficientthe critical gaseous components from a molten via asticky to a solid phase. The article outlines the mo-dem gas cooling methods combined with efficientheat recovery. Examples of the alternative use of re-covered steam energy are outlined; as e.g. drying ofconcentrate and power generation. The heat trans-fer impact of the insulating dust is called fouling andcircumstances causing fouling are described. Modemcooling surface design and cleaning techniques tokeep fouling in reasonable limits are described. Leak-age and false air ingress into the gas handling linesoften limits smelting capacity. The objective is gener-ally to minimize the infiltration of air but it still takesplace at open interfaces (e.g. at reactor hood, feedport). Leakage—air at furnace roofs for example—can be reduced to a minimum by adopting the pres-sure gas sealing used at present In-Bath-Lance fur-naces. Modernization and optimization methods tode-bottleneck existing waste heat boiler gas coolingcapacity by highly efficient surface cleaning systemsand false air avoiding (e.g. bundle roof boxes, dustdischarge) are detailed described.

2:50 PMAnalysis of Recent Advances in Sulfuric Acid PlantSystems and Designs (Contact Area): Leonard JoelFriedman1; 1Acid Engineering & Consulting, Inc., P.O.Box 811539, Boca Raton, FL 33481-1539 USA The contact process for the production of sulfuricacid has been used commercially since before theturn of the century (1880’s), and rapidly replaced thechamber process after the development of vanadiumcatalysts in the early 1900’s (1910’s-1920’s). Plant sizehas increased from a few tons per week to single trainunits in excess of 4,000 tons per day. Much of the his-tory of the contact process is in the minds of the fewremaining early process pioneers that started in theindustry in the 1920’s and 1930’s, and in sulfuric acidindustry books published in 1921, 1925, 1936, and thelast Deucker and West in 1959. Since those not famil-iar with history are doomed to repeat the failures andmistakes of the past, this paper includes a brief his-tory of the contact process along with the history anddevelopment of equipment and materials in eachequipment area of the process. The main focus ofthe paper is to present the development and analysisof equipment and materials in the contact session ofthe sulfuric acid plant from the dry tower to stack.Note: Previous works by L. J. Friedman provide analysisof developments in the gas cooling, cleaning andpurification sections of metallurgical and spent acidregeneration plants. The discussion of each equip-ment area includes the history and development ofthe equipment, current design alternates, and ananalysis of each leading to a recommended design.Good designs are highlighted, and gimmicks andmarginal problems prone designs exposed.

3:15 PMGas Handling and Cleaning at the Potrerillos Smelter:Leonel Contreras1; Pedro Reyes1; Benjamin Martinich1;René Bustamante2; 1Codelco-Chile, División El Salva-dor, El Salvador, Chile; 2Universidad de Santiago deChile, Departamento de Ingeniería Metalurgia, Av.Libertados Bernardo O’Higgins 3363, P.O. Box 10233,Santiago, Chile The gas treatment system, MALIGAS (in SpanishMAnejo y LImpieza de GASes which means handlingand cleaning of gas), is part of the Codelco-ChilePotrerillos Smelter decontamination plan, which in-cludes the newly designed system for the cooling andcleaning of the gas generated from a Teniente Con-verter and four Peirce Smith Converters. The gas gen-erated in the process is captured by water cooledhoods and mixed with air. Then the gas enters a cool-ing pre-chamber which utilizes a water cooled screento capture and remove the coarse and semi-fusedparticles. At this stage, the gas loses a portion of itsheat with temperature falling below 608ϒC which is anecessary condition to avoid damage to the pipes,ducts and other metallic structure of the gas handlingsystem. The gas is further cooled at the RadiationCooler to a temperature ranging between 315 and380ϒC. The gas is conditioned to avoid damage tothe electrostatic precipitators that are designed toclean the gas by removing significant amount of dustsfrom the gas stream. This gas stream is currently dis-charged to the stack, however, it will be treated in asulfuric acid plant that is currently under constructionand is scheduled for commissioning during the sec-

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ond half of 1999. The gas handing and cleaning sys-tem has been operated without any significant inter-ruptions. Minimal emissions of SO2 and dusts in thework place are noted. The system requires minimummaintenance. The key to the high availability of thesystem is due to the good performance of he Radia-tion Cooler, which efficiently cools the gas before en-tering the electrostatic precipitators (ESPs). This enablesthe ESPs to remove the dusts efficiently.

3:40 PM Break

4:10 PMProcess Gas Handling in Copper Metallurgy: M. A.Cocquerel1; C. Cuadra2; T. Moya2; 1Kvaerner E&C,Dept. of Tech., 12657 Alcosta Blvd., San Ramon, CA94583 USA; 2Kvaerner E&C, Pyrometallu. Specialists,Santiago, Chile External process energy requirements and air pol-lution control regulations formulated to limit particu-late and SO2 emissions are impacting on smelting andconverting technologies and the corresponding pro-cess and secondary gas handling systems. This pa-per presents an overview of the different technicalsolutions used for cooling and dedusting the processgases in the different pyrometallurgical copper con-centrate stages, including: drying, smelting, convert-ing, slag cleaning and fire refining. The main prin-ciples of the process gas handling systems are pre-sented and a qualitative technical and economicalcomparison is discussed in relation to processchanges, energy recovery and marketing or dispos-ing of the various sulphur fixation by-products. Finally,a brief review of the methods for fixing sulphur con-tained in the process and secondary gases is pre-sented.

4:35 PMPeirce-Smith Converter Hood Improvements at BHPCopper: Ovidiu Pasca1; John Bryant1; Paykan Safe2;Brian Wiggins2; 1BHP Copper, San Manuel, AZ USA;2Gas Cleaning Technologies, Dallas, TX USA Several improvements in converter equipment andoperation at BHP Copper have reduced the convertercycle time as necessitated by an increase in flash fur-nace output. The resulting higher intensity perfor-mance of the Peirce-Smith Converters has had a majorimpact on the dust handling and off-gas cleaningsystems. This paper describes work carried out on thedesign of a new converter hood with particular refer-ence to the thermal analysis and hood performanceaspects. Changes in converter cycle time and cam-paign life as result of the process and equipment im-provements are discussed in a separate paper

5:00 PMUpgrading of the Teniente Technology: Pedro Mo-rales C.1; Roberto Mac-Kay S.2; 1Codelco-Chile, Di-rect. of Tech. Innov. and Res., Huérfanos, Santiago1270 Chile; 2Codelco-Chile, El Teniente Div.,Caletones Smelter, Millan, Rancagua 1040 Chile From its beginning in the 1970's, the Teniente Con-verter has consistently achieved continuous improve-ment, and has contributed to the competitiveness andsustainability of Codelco’s copper operations. Thelater introduction of the Slag Cleaning Furnace tech-nology has helped to create a full technology pack-age, referred to as the Teniente Technology. This pa-per outlines the features of a new research and inno-

vation program designed to bring the Teniente Tech-nology as a modem, competitive technology into the21st century. The overall objectives and features ofthe program are described and discussed. It is fullyanticipated that these activities will help position theTeniente Technology as a world-class modem tech-nology, well-integrated and operating in a fully con-tinuous mode in conjunction with the other units atthe plant, a competitive technology which operatesin harmony with respect to environmental regulations.

5:25 PMModification of the Mount Isa Copper Converters toFeed a New Sulphuric Acid Plant: Richard Hollis1;Adrian Werny1; Gregory Yeowart2; 1Fluor Daniel PtyLimited, 300 Ann St., Brisbane 4000 Australia; 2MountIsa Mines Limited, Mt. Isa, Queensland 4825 Australia The Mount Isa copper smelter was expanded in1998 to a capacity of over 250000 t/y anode copper.This tonnage will be produced from a single streamconsisting of an Isasmelt smelting furnace, and fourPeirce-Smith converters—one of which was installedas part of the expansion project. During the courseof the expansion project Mount Isa Mines Limited(MIM) signed an agreement with WMC Fertilizers, Ltd.(WMCF) to supply sulphur containing smelter gasesover the fence to a new sulphuric acid plant to bebuilt by WMCF. This will result in a further increase incopper production by reducing the time when smelt-ing is curtailed by Air Quality Control restrictions. Aswell as the need to modify the primary gas system toconnect to the acid plant, the hoods and crossoverducts and their support structures on the original threeconverters require placement, and secondary venti-lation was also needed to improve converter aislehygiene. Each of these areas was addressed by theproject. Preliminary ideas for carrying out the modifi-cations were found to have a serious impact on con-verter aisle operations, and would have led to a pro-duction loss of over 50000 tonnes of copper. Follow-ing benchmarking in other copper smelters, a suit-able construction plan was developed and carriedout to minimise this loss. This paper describes the meth-odology and construction plan adopted.

Smelting: Technology Development,Process Modeling and Fundamentals:Technology Development II

Monday PM Room: GoldwaterOctober 11, 1999 Location: Pointe Hilton Resort

Session Chairs: Jan Matousek, 8547 E. ArapahoeRd., #J149, Greenwood Village, CO 80111-1430 USA;Antonio Luraschi, INDEC, International EngineeringConsulting Services, Avda. Providencia 2653, Of.512, Santiago, Chile

2:00 PMConverter and Bath Smelting Vessel Design - BlastDelivery and Tuyere Performance: A Reassessment ofDesign Characteristics: A. E. Wraith1; P. J. Mackey2;C. A. Levac3; P. Element4; 1University of Newcastle,

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Dept. of Mech., Mats. and Manuf. Eng., Newcastleupon Tyne NE1 7RU UK; 2Noranda Technology Cen-tre, Pointe Claire, Québec, Canada; 3Fonderie Horne,Metallurgie Noranda, Noranda-Rouyn, QuébecCanada; 4Noranda, Inc., Mines Gaspe, Murdochville,Québec, Canada The tuyere flow rates of Peirce-Smith converters andbath smelting reactors are rendered particularly sen-sitive to accretion formation, bath depth variationsand the general aerodynamic design of the blastdelivery system by the limited pressure-flow proper-ties of the conventional single stage centrifugalblower. This sensitivity is examined in terms of tuyerepractice, vessel management and fixed engineeringparameters for Peirce-Smith converters and theNoranda Reactor by use of the flow resistance fac-tor, R*. New understanding of the effect of accretiongrowth on the flow behaviour of individual tuyeresshows that blowing rates and hence throughputscould be optimised by careful attention to operatingdetail even within present plant constraints. The con-cept of the resistance vector is introduced to eluci-date comparisons between different practices andto provide reference standards for optimisation. Onthis basis, the benefits of introducing quite moderatechanges in the pressure-flow properties of the blastdelivery system are considered. In view of recent de-velopments in the flexible use of converters as hybridbath smelting vessels for matte production, the foun-dation is now laid for a searching consideration ofrelationships between vessel volume and shape, blow-ing requirements, tuyere performance and produc-tion rates, the detail of which will be examined moreappropriately in a forthcoming paper.

2:25 PMHigh Oxygen Shrouded Injection at Falconbridge: A.A. Bustos1; J. P. Kapusta1; B. R. Macnamara2; M. R.Coffin2; 1Air Liquide Canada, Inc., 1250, BoulevardRené-Lévesque Ouest, Montréal, Québec, CanadaH3B 5E6; 2Falconbridge Limited, Falconbridge, Ontario,Canada POM 1S0 Four Air Liquide Shrouded Injectors (ALSI) were in-stalled and operated for over one year in a Peirce-Smith converter at the Falconbridge nickel smelter inFalconbridge, Ontario, Canada. A shrouded injec-tor consists of an inner pipe and an annulus, throughwhich high oxygen enriched air and nitrogen flow,respectively. The nitrogen cools the injector and pro-tects the refractory in the vicinity of the injector tip,allowing for substantial increases in oxygen flow ratesto the converting reactions. Several injector designswere tested to study the effect of changes in the cross-sectional area and changes in the entrance geom-etry of the annulus. An optimum design would mini-mize the injection pressure required for a given flowrate to achieve choked flow conditions at the tip ofthe injector. The operation of the ALSI was simple anddid not require any special care or maintenance, ei-ther between blows or between converter cycles. Inparticular, the shrouded injectors did not requirepunching, as is the case with conventional tuyeres. Interms of refractory performance, the ALSI, operatingat 30-40% oxygen enrichment, were superior or equalto the conventional tuyeres, which operated at 21-23% oxygen. The results of the demonstration programled Falconbridge Limited to implement the ALSI tech-nology on a commercial scale. The paper presents

the demonstration program results in terms of gas flowrates, accretion formation, punchless operation andrefractory wear.

2:50 PMA Fluid Dynamic Simulation of a Teniente Converter:M. Rosales1; R. Fuentes1; P. Ruz1; Jorge Godoy2; 1Insti-tute for Innovation in Mining and Metallurgy (IM2),Avenida del Parque 4980, Ciudad Empresarial,Huechuraba, Santiago, Chile; 2CODELCO-Chile, ElTeniente Div. Using the k-ε turbulence model, a mathematicalfluid dynamics simulation of the flow characteristicsin a Teniente Converter has been conducted. Twocases were studied: Transversal sections in the smelt-ing-converting zone; and a three-dimensional simu-lation that includes the walls of the reactor. The cal-culations give the velocities field, the gravity wavesamplitude, the splashing behaviour, the phase distri-bution and the shear stress distribution. The latter helpsto explain the pattern of refractory lining wear. Thecalculation includes the approximate shape and di-mensions, and the eventual coalescence of bubbles.

3:15 PMA Waterless Caster for Matte/Slag Granulation: FrankMucciardi1; Enzo Palumbo2; Ning Jin3; 1McGill Uni-versity, Dept. of Metall. Eng., 3610 University St.,Montreal, Québec, Canada H3A 2B2; 2Noranda Tech-nology Centre, 240 Hymus Blvd., Pointe-Claire,Québec, Canada H9R 1G5; 3McGill University (nowwith Cosworth Technologies, Detroit, MI USA) With the increasing trend to continuous smeltingand converting, granulation of copper matte is gain-ing prominence as a means of decoupling the smelt-ing and converting operations. Moreover, granula-tion is also being seen as a possible avenue to usinghigher grade oxygen in converters. By feeding coldsolid matte, the oxygen concentration can be in-creased to compensate for the lower enthalpy feed.This leads to a higher grade of S02 in the off gas anda lower total flow rate. Current granulation technol-ogy relies on the cooling of a falling matte film bywater jets. This technology while effective has severaldrawbacks including those related to safety. Norandaand McGill University have developed a new process(patent pending) for solidifying copper matte (orslag). It overcomes many of the negatives of currenttechnology. The system is based on an air cooledtwin roll caster. This new system uses no water andinstead incorporates heat pipe technology to trans-fer the heat from the solidifying matte to the coolingair to produce a thin strip of 1 to 2 mm in thickness.Testing of a prototype unit demonstrated its viability.This paper describes this newly developed, twin rollcasting system that is completely waterless. The ad-vantages of this process as well as the findings fromseveral tests are also detailed.

3:40 PM Break

4:10 PMFerrous Calcium Silicate Slag to be Used for CopperSmelting and Converting: Akira Yazawa1; YoichiTakeda2; Shigeatsu Nakazawa3; 1Tohoku University,16-32 Niizaka, Aoba-ku, Sendai 981-0934 Japan; 2IwateUniversity, Dept. of Matls. Sci. and Tech., Ueda 4-3-5,Morioka 020-0066 Japan; 3Tohoku University, Dept. ofMetallu., Grad. Schl. of Eng., Aoba-ku, Sendai 980-

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8579 Japan The composition of ferrous calcium silicate slag islocated on the tie line between FeOx and calciumsilicates in ternary FeOx -SiO2-CaO system. This slag hasnever been used as copper smelting slag because ofhigh sulfidic copper solubility. However, when the dis-solved copper in slag is just oxidic, as in direct whitemetal production or in converting process, this slag isquite attractive and can be regarded as the thirdcopper smelting slag after fayalite and calcium fer-rite slags. Based on the authors’ studies on phase sepa-ration thermodynamics and laboratory experiments,it was clarified that the oxidic copper loss in this fer-rous calcium silicate slag become the minimum notonly %Cu in slag but also the total copper loss whenthe amount of slag is taken into account It has beenproven that calcium ferrite slag is suitable for con-tinuous converting where the dissolved copper is ox-idic, but there exist some drawbacks such as limitedsolubility of silica, low lead removability and too highfluidity. To overcome these difficulties accompany-ing traditional slags, ferrous calcium silicate slag isthe hopeful alternative. In view of the general trendsof modem copper smelting processes, the interestingfeatures of this new slag system are discussed.

4:35 PMTechnology for Decreasing Refractory Wear in theMitsubishi Process: Fundamental Research and itsApplication: Fumito Tanaka1; H. Sato1; NozomuHasegawa1; 1Mitsubishi Materials Corporation, Cntrl.Rsch. Instit., 1-297 Kitabukuro-Cho, Omiya, Saitama330-8508 Japan In April 1999, a two-year campaign of the Mitsubishifurnaces was achieved at Naoshima Smelter; thepresent one is expected to be extended much longer.An overview of basic technology for decreasing re-fractory wear in the Mitsubishi Process is presented.One of the main features of the process is the use oftop blowing lance technology which has a differenteffect on the furnace refractory than other conven-tional processes. The refractory wear of concern ishearth wear caused by top blown powder injection,wear of the side wall caused by splashing droplets,and wear of the bath level refractories caused bysurface waves of melts in the furnace. These havebeen systematically investigated for many years. Thispaper describes the results of various model tests andtheir application to practical furnace design andoperation.

5:00 PMInteraction between a Gaseous Vertical Jet and a Liq-uid Surface - A Theoretical and Experimental Study:L. Salinas1; R. Fuentes1; 1Institute for Innovation in Min-ing and Metallurgy (IM2), Avenida del Parque 4980,Of. 131, Huechuraba, Santiago, Chile Lance injection of gas and particles into a moltenbath is currently practised in metallurgical processes(Mitsubishi lances for example). Several experimentaland theoretical studies have been conducted in thepast on this topic. However, neither detailed calcula-tions nor experimental studies of local flow patternshave been published. In the present work, a numeri-cal simulation of the interaction of a gaseous verticaldescending jet and a liquid surface was done, usingthe turbulence k-ε model. There is a fair agreementbetween the calculated and the experimental val-

ues. The results of this study demonstrate that it is cru-cial that the gas jet velocity profile and turbulent char-acteristic are correctly formulated in order to correctlysimulate the system.

5:25 PMExtending Lance Life in Top Blowing: Frank Mucciardi1;G. Zheng1; Ning Jin2; 1McGill University, Dept. ofMetall. Eng., 3610 University St., Montreal, Québec,Canada H3A 2B2; 2McGill University, now withCosworth Technologies, Detroit, MI USA While flash smelting and converting are capturinga greater share of the market, injection through cir-cular injectors will remain with us for the foreseeablefuture. The use of top lances for injection is a key fea-ture in several processes (e.g. Mitsubishi, Ausmelt).Tuyeres, on the other hand, are incorporated into anumber of processes (e.g. Noranda, Peirce-Smith). Todate no lances or tuyeres are cooled by an externalsource. The reagent provides the bulk of the cooling.With limited cooling, it is normal to have substantialwear on the nozzles - especially in the case of lances.To overcome the issue of wear, a new patented in-jector (lance or tuyere) has been developed byNoranda and McGill University. This novel unit is basedon heat pipe technology. It can operate for an ex-tended period of time without wearing. Enhancedlance/tuyere life is achieved by operating the injec-tor at a low enough temperature that promotes theformation of a thin frozen layer on the outer body ofthe unit. The vaporizing and condensing substancewithin the unit acts to cool the high heat flux portionsand dissipate the heat to areas of low heat flux out-side the vessel. A fairly large number of tests havebeen conducted with a prototype unit. The tests haveshown that the heat pipe lance is a viable unit. In thispaper is detailed a test which illustrates how the lancefunctions when pure oxygen is injected into coppermatte. In addition, the findings from a basic study ofa heat pipe in high heat flux environments are alsopresented.

Plenary Lectures: Session II

Tuesday AM Room: Flagstaff/Goldwater/ Indigo/Jerome

October 12, 1999 Location: Pointe Hilton Resort

Session Chairs: S. Demetrio, ConOpti S.A., Cerro SanRamon 1491, Las Condes, Santiago, Chile; C. Diaz,University of Toronto, c/o Dept. of Metallurgy andMatls. Sci., Toronto, Ontario, Canada

8:30 AMThe Draft GBN Global Scenarios and the Forces Driv-ing Them: Peter Schwartz1; Steven Weber1; 1GlobalBusiness Network, 5900-X Hollis St., Emeryville, CA 94608USA This paper presents GBN’s “Global Scenarios” forthe first decade of the 21st century. We describe a setof key scenario actors and develop 6 driving forcesin demography, technology, climate change, mac-roeconomic change, globalization, and geopolitics.

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We argue that a set of major challenges to world sys-tems of commerce and politics will coalesce in thenext several years. We develop four scenarios whichdiffer according to how these challenges are hand-led, and which scenario actors play the key roles inmanaging the transition.

9:15 AMThe Financial Performance of the Copper Industry:Some Comparisons: Peter Kettle1; 1CRU InternationalLimited, 31 Mount Pleasant, London WCIX OAD En-gland This paper describes the performance of the cop-per industry over a period of some two decades andexamines the theme that improvements in operatingefficiency have not been matched by improved re-turns on capital. The financial performance of thecopper industry is analysed using CRU’s MICA data-base. Regression analysis indicates a two percentagepoint increase in operating margins but no increasein returns on capital. The gain in operating efficiencyappears to have been mainly achieved in the mid1980’s. The investment boom of recent years has re-sulted in a rapid increase in the industry’s level of debtand gearing ratio (now some 47%). Data on 44 cop-per mine projects is used to show the linear relation-ship between scale and capital costs. Typically newcapacity costs some US$5,000/tpy. The relationshipbetween cash costs and capital intensity of projectsis also plotted. The greater attention now being fo-cused on efficient use of capital means that capitalintensity rankings will become increasingly importantin determining which projects go ahead.

10:00 AM Break

Copper Applications and Fabrication:Fabrication

Tuesday AM Room: CopperOctober 12, 1999 Location: Pointe Hilton Resort

Session Chair: Mahi Sahoo, Natural ResourceCanada, Ottawa, Ontario, Canada K1A 0G1

10:30 AMMechanical Properties of Selected Brasses Cast in Per-manent Molds: F. A. Fasoyinu1; R. Bouchard1; J.Thomson1; M. Sahoo1; 1CANMET, Matls. Tech. Lab.,568 Booth St., Ottawa, Ontario, Canada K1A 0G1 The mechanical properties of yellow brass(C85800), high strength yellow brass (C86300), andhigh manganese brasses (C99700 and C99750) castin permanent molds have been studied. The tensileproperties as well as fracture and impact toughnessof these alloys are strongly dependent on the chemi-cal composition. Alloys and/or compositions exhibit-ing relatively high zinc equivalent often exhibited highultimate tensile strength and yield strength with sig-nificant reduction in ductility (% elongation). In orderto achieve optimum properties with a good balancebetween strength and ductility, a calculation of thezinc equivalent before alloy preparation can be use-ful.

10:55 AMRheology and Metal Forming of Fire-Refined Copper(FR): Carlos Camurri1; 1Concepción University, Dept.of Metall., Casilla 53-C, Concepción, Chile Results from the Metallurgical Department of theUniversidad de Concepción showed that fire-refinedcopper could be rolled without previous remeltingfor deoxidation. The goal of this work was to deter-mine the rheology of fire-refined copper using tensiletests at different temperatures and strain rates, as wellas Ford plane compression tests. This was done in or-der to simulate and calculate rolling process vari-ables. For rheology hardness coefficients, values be-tween 0.28 at 600ϒC and 0.46 at ambient tempera-ture were obtained. The sensibility coefficient for strainrate m varied between 0.056 at 600ϒC and 0.006 atambient temperature. The activation energy for plas-tic flow Q in the considered temperature range wasfound to be 1436 cal/mol.

11:20 AMThe Effect of Nickel on the Mechanical Properties ofHigh-Strength Yellow Brass: D. G. Schmidt1; 1R. Lavinand Sons, Inc., 3426 S. Kedzie Ave., Chicago, IL 60623USA Tests were conducted on C86200 high-strength yel-low brass in order to ascertain the effect of a lowlevel of nickel on the mechanical properties of thisalloy. A series of two alloys was studied, one of whichhad a nickel content of 0.85% and the other with<0.05% nickel. Copper and aluminum content rangedfrom 62.5% and 64% and 3.2% to 4.6% respectively.When compared by zinc equivalents, a nickel addi-tion of 0.75% in high-strength yellow brass does notact like copper but raises the tensile strength, 0.5%yield strength and BHN while lowering the elonga-tion.

11:45 AMGrain Refinement of Copper Base Alloys: M.Sadayappan1; F. A. Fasoyinu1; M. Sahoo1; 1MaterialsTechnology Laboratory (CANMet), 568 Booth St., Ot-tawa, Ontario, Canada K1A 0G1 The grain refinement characteristics of four low-leadand lead-free copper base alloys for plumbing ap-plications were investigated. These are leaded yel-low brass (C85800), SeBiLOY III (C89550), silicon brasses(C87500 & C87800) and silicon bronzes (C87600 &C87610). Boron and zirconium were found to be themost effective grain refiners for copper alloys pro-duced using the permanent mold cast processes. Thestudy indicates that the type of grain refiner to beused is dependent on the alloy type, alloying con-stituents and their content. After grain refinement, hottearing resistance of the alloys was improved but me-chanical properties remained unaffected. Alloys re-fined with boron are prone to the formation of hardspots, which will have adverse effect on the surfacequality of the castings during polishing and buffing.

12:10 PMImproved Rod Plant Level Control with UNAC: A. A.Shook1; C. A. Shelton1; 1BHP Copper Smelting andRefining, 200 S. Redington Rd., P.O. Box M, SanManuel, AZ 85631 USA For relatively little capital outlay, the metal deliv-ery control systems in the BHP Copper Rod Plant atSan Manuel was significantly upgraded using theUNAC process simulation and control system (CICS

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Automation, Newcastle, Australia). An accurate simu-lation of the metal delivery process was developedwith UNAC, which was then used to design robustcontrollers capable of dealing with plant complexi-ties such as noise, time delays, and nonlinearities. Thiscontroller was implemented online using UNAC.Thanks to the extensive preparatory simulation, thecontroller worked immediately and required no ad-ditional online “tuning.” Operator response has beenfavorable, and the UNAC control system has becomepart of the standard operation of the plant.

12:35 PMApplication of Mechanical Alloying Processing to theFormation of Copper-Carbides Alloys: VictorVergara1; M. López1; R. Benavente1; C. Camurri1; B.Cartes1; J. Jiménez2; 1University of Concepción, Dept.of Metallu. Eng., Casilla 53-C, Concepción 00187Chile; 2Centro Nacional de Investigaciones Metalur-gicas, Av. G. del Auro, Madrid 8-28040,Espana Four copper composites were obtained by me-chanical alloying, using as dispersed phases of fourcarbide powders; they were: boron carbide, chro-mium carbide, silicon carbide and zirconium carbide.The purpose of this work was to study some charac-teristics of these compounds and their feasibility foruse as materials for electrical equipment. Raw mate-rials used were copper powder finer than 150 mesh,and 2-4 vol % of powder carbides finer than 325 mesh.The alloying process was carried out using both aSpex 800-D mill with tungsten jars and balls and ahardened stainless steel jar and balls, the purpose ofwhich was to measure the degree of contaminationinduced by the milling media. The changes in par-ticle size, morphology and microstructure of copperalloys were studied with SEM and TEM for each al-loyed powder. The degree of saturation of copperby the carbides was measured by X-ray diffraction.Sound samples were obtained by hot isostatic press-ing at 1073ϒK. The best characteristics were obtainedfor the compound copper-chromium carbide, basedon their hardness, tensile strength and electrical con-ductivity values. The other alloys failed due to theirexcessive brittleness after hot pressing.

Electrorefining: Refinery Operations III

Tuesday AM Room: IndigoOctober 12, 1999 Location: Pointe Hilton Resort

Session Chairs: J. Garvey, Cyprus Miami MiningCorporation, Claypool, AZ 85532 USA; M. RamosRada, Mexicana de Cobre S.A. de C.V., RefineriaLa Caridad, Nacozari, Sonora, C.P. 84340 Mexico

10:30 AMAntimony Removal by Ion Exchange in a ChileanTankhouse at the Pilot Plant Scale: E. A. Román1; J.C. Salas1; J. E. Guzmán2; S. Muto3; 1IM2, Instituto deInnovación en Minería y Metalurgia, S.A., Fi l ialCodelco-Chile, Av. del Parque 4980 Of. 131, Huechu-raba, Santiago, Chile; 2División Chuquica-mata,Codelco-Chile, Chuquicamata, Chile; 3Mesco, Inc.,Eng. Div. of Mitsui Mining and Smelting Co., Ltd., 2-10-5 Ryogoku, Sumida-ku, Tokyo 130 Japan

An ion exchange pilot plant, provided by Mesco,Inc., was tested for antimony control in the electro-lyte at three Chilean tankhouses for copper electrore-fining: Chuquicamata, Potrerillos and Enami-Venta-nas. The pilot plant, with a nominal extraction ca-pacity of 1.2 kg Sb/day, worked connected to bothexperimental and commercial circuits, performing atotal of 310 loading and elution cycles. An innova-tion in this process is the use of a chelating organicelution reagent, which presents some advantagesover the traditional 6N HCl. This new eluent is ame-nable to continuous regeneration and recycling withhigh recovery efficiency. Antimony removal startingat initial concentrations of 0.5 to 0.6 g/l of Sb downto steady concentrations of 0.1 to 0.06 g/l Sb, resultedin the production of High Grade copper cathodeswith Sb contents below 0.1 ppm. Anodic slimesshowed Sb contents below 1%.

10:55 AMReduction of Silver Losses during the Refining of Cop-per Cathodes: P. Barrios1; A. Alonso1; U. Meyer1; 1At-lantic Copper, S.A., Avda. Francisco Montenegro, s/n, Huelva E-21001 Spain Over a period of one year, an in-depth investiga-tion was carried out in a conventional copper refin-ery to understand the behaviour of silver in copperelectrolysis. The increase in silver content in the cath-odes increases almost lineally with the duration ofelectrolysis, and the silver content of the electrolytebetween the electrodes shows similar behaviour. Thesilver content of the cathode deposited daily de-pends directly on the silver concentration of the elec-trolyte and this, in turn, is strongly influenced by itsinternal temperature. The average temperature be-tween the electrodes rises from the first to the secondand to the third crop, because of the increase in thedistance between the electrodes and the heat gen-erated by the passage of the current. The mecha-nism of dissolution of silver from the anode, and itspassage to the cathode, are discussed. Following thechange to the Isa system, it was proved that the re-sults and conclusions are analogous. Based on theseresults, a reduction of more than 20% in silver losses inthe cathodes was achieved.

11:20 AMCurrent Efficiencies at High Current Density for Vari-ous Cathode Cycles: I. M. Santos Moraes1; 1CaraibaMetais S.A., Via do Cobre n° 3700 A.I.O. - COPEC,Dias D’Ávila, Bahia 42-850-000 Brazil Achieving high current efficiencies when operat-ing at high current densities is a goal for every refin-ery, whether conventional or permanent cathodetechnology is employed. To obtain higher current ef-ficiency at increased current density at Caraiba’sTankhouse, the production team decided to changethe cathode cycle from eleven to thirteen days, re-ducing cathode cycle to one per anode cycle. Theidea was to reduce the anode-cathode spacing andconsequently reduce the potential for short-circuitingthem. With respect to current efficiency, the overallresult was not much better than that obtained withthe normal operating conditions. A new attempt toobtain higher current efficiency at high current den-sity was implemented by going back to two cath-ode cycles per anode cycle, this time reducing cath-ode life to ten days. This approach yielded the high-

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est current efficiencies. This paper presents the datagenerated with the three operating conditions: nor-mal practice, a single cathode cycle per anode cycle,and two cathode cycles per anode cycle with a re-duced cathode cycle time. It compares the produc-tivity achieved with each set of operating conditions.An analysis of the main operating parameters as wellas the advantages and disadvantages involved witheach condition is also presented for future reference.

11:45 AMMaintaining High Efficiencies While Increasing Cur-rent Density: F. Begazo1; R. M. Underwood1; A. G.Storey1; V. R. Alarcón1; 1Southern Peru Copper Cor-poration, Ilo, Peru The most common approach to increase produc-tion in copper refineries is to increase current densi-ties. However, if these increases are not well thoughtout beforehand and are not properly and effectivelycontrolled, the end results could be reduced plantperformance and a deterioration in cathode qual-ity. Both of these factors result in lower efficienciesand increased costs. At the Ilo Refinery of SouthernPeru Copper Corporation, a modernization and ex-pansion program was implemented shortly after theRefinery was purchased from Minero Peru, in 1994.This program was intended to increase productionfrom 195,200 mtpy of cathode to 227,000 mtpy over a3-year period. Part of this production increase wouldcome from increasing current density. During the pe-riod from 1994 to 1997, current density at the Ilo Refin-ery was increased from 218 A/m2 to 230 A/m2, whileplant efficiencies were maintained at consistently highlevels. The current efficiencies were maintained at>97.5% and time efficiencies were maintained at >98%.During 1998, additional increases in current densitywere implemented while the high plant performancewas maintained at the same levels. By the end of 1998,the current density was 241 A/m2, while current effi-ciency and time efficiency of 98% were maintained.This paper describes the control processes used atthe Ilo Refinery to maintain high plant performancelevels while increasing the current density. Addition-ally, expected plant performances from extended testprograms at current densities up to 280 A/m2, for fu-ture production increases, are reviewed and dis-cussed.

Hydrometallurgy: Biohydrometallurgy

Tuesday AM Room: HopiOctober 12, 1999 Location: Pointe Hilton Resort

Session Chair: Corale Brierley, Brierley ConsultancyLLC, Highlands Ranch, CO 80163 USA

10:30 AMCopper Bioleaching: State-of-the-Art: Corale L.Brierley1; James A. Brierley2; 1Brierley Consultancy LLC,P.O. Box 260012, Highlands Ranch, CO 80163 USA;2Newmont Metallurgical Services, 10101 E. Dry CreekRd., Englewood, CO 80112 USA Bioheap leaching, commercially applied for sec-ondary copper ores and agglomerates, is rapidly

gaining popularity. Bioleaching of chalcopynite con-centrates is imminent. Copper bioheap leaching en-compasses the bioleaching of acidified and agglom-erated coarse, secondary copper ore, stacked onpermanent or on/off pads. The stacked ore is irrigatedwith raffinate containing bacteria. LME-grade cath-ode copper is produced by SX/EW. Low capital andoperating costs, rapid start-up, environmental ben-efits, operational simplicity and a good performancerecord make bioheap leaching an attractive tech-nology. This paper looks at the state-of-the-art of cop-per bioheap leaching and chalcopyrite concentrateleaching, the risks, the benefits, costs, bioheap per-formance and the future prospects of copperbioleaching.

10:55 AMBacterial Heap Leaching of Covellite: Sergio Bustos1;Romilio Espejo1; Cecilia González1; Randolph E.Scheffel2; 1Lakefield Research Chile S.A., Los Ebanistas8585, La Reina, Santiago, Chile; 2Metallurgical Con-sultant, 25778 Summergreen Ln., Golden, CO 80401USA Covellite resulting from an original 0.5 % Cu(tot)chalcocite ore has been leached in columns at dif-ferent temperatures, in the lower range of 10 - 20ϒC,under acid-ferric bacterial leaching conditions. Dis-solution of copper from covellite depends on the rateand extent of sulfide oxidation by ferric ion. While it isrecognised that the dissolution of sulfide minerals iselectrochemical in nature, an apparent chemicallycontrolled dissolution pattern was measured withactivation energy of 78.09 kJ/mol (18.66 kcal/mol).Ferric iron is the main oxidant and its production andavailability will depend on the bacterial activity de-veloped in the system. This activity is characterisedby the population size and by the specific oxidationrate of the bacteria. Bacterial growth was followeddirectly by the number of bacteria appearing in thecolumn effluent solutions and indirectly by the gen-eration of ferric iron or by the total oxidation observedin the columns. These results have been interpretedby using the heap oxidative capacity parameter,which indicates an equivalent ferric production ofabout 0.07-0.15 kg Fe +3/t/day at 20ϒC. Although bac-terial activity decreases to about 0.03 kg Fe+3/t/daywith decreasing temperature, a significant bacterialoxidation is still observed at 10ϒC. However, extendedlag times are observed, which delay the start of bac-terial growth to times concurring with covellite leach-ing. Under these conditions, bacterial activity is dis-played through a population controlled by the rateat which ferrous iron is released from the reducingcovellite surface. These results suggest the potentialbenefit of including some kind of inoculation whenoperating at lower temperatures. Also, heat loss con-trol and/or heat addition to the heaps should beconsidered during process design and operation offerric bacterial heap leaching of secondary coppersulfide ores at temperatures lower than 20ϒC.

11:20 AMBioleaching of Chalcopyrite in the Presence of Silver:Solids Characterization: A. Alvarez1; M. LuisaBlazquez1; Antonio Ballester1; Felisa Gonzalez1; E. Sali-nas2; Monserrat Cruells3; Antonio Roca3; 1UniversidadComplutense, Dept. Ciencia de Materiales, Facultadde Ciencias Quimicas, Madrid 28040 Spain;

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2Universidad Autónoma de Hidalgo, Instituto deCiencias de la Tierra, Pachuca, Hidalgo, Mexico;3Universidad de Barcelona, Dept. d’EnginyeriaQuimica i Metallurgia, Facultat de Quimica, Marti iFranques 1, Barcelona 08028 Spain In this work, mesophilic and thermophilic cultureshave been used in the presence of silver as a cata-lyst. Chalcopyrite and byproducts of bioleaching werecharacterized in order to: a) obtain information aboutthe kinetics control of the process, and b) explain thedifferent behaviour observed during the mineral at-tack. With thermophilic microorganisms (68ϒC andNorris medium as nutrient) the reaction stopped atapproximately 65% copper extraction, with and with-out Ag ion addition as a catalyst. The remaining chal-copyrite appears surrounded by hydroniurn jarosite(with ammonium ion in substitution in the “alkalinesite”), goethite and elemental sulphur. With mesophiliccultures (35ϒC and 9K medium as nutrient) the reac-tion stopped at approximately 25% copper extrac-tion (without Ag) and approximately 85% extraction(with Ag). In both cases, the remaining chalcopyritewas surrounded by agglomerates of ammoniumjarosite (with hydronium ion substitution in the “alka-line site”) and some iron oxides and/or hydroxides.

11:45 AMThe Application of Bacterial Sulfate Reduction Treat-ment to Severely Contaminated Mine Waters: Resultsof Three Years of Pilot Plant Testing: R. W. Hammack1;H. Dijkman2; 1U.S. Dept of Energy, Fed. Energy Tech.Ctr., P.O. Box 10940, Pittsburgh, PA 15236 USA; 2PaquesBV, Balk, The Netherlands Results for the treatment of a problematic miningwastewater using bacterial sulfate reduction (BSR) arepresented. Specifically, a BSR pilot treatment plant(250 L per day) was used to treat Berkeley Pit simulantto discharge standards with the selective recovery ofseparate Cu-and Zn-sulfide concentrates. Concen-trates recovered in these tests contained greater than50% of the target metal and met specifications forsale to existing smelters. The biological componentof the treatment was found to be surprisingly robust.Scaling and solid/liquid separation problems were en-countered but considered normal for sulfide treatment.For Berkeley Pit water, capital costs for BSR treatmentwas found to be comparable to high-density sludgelime treatment. The value received from the sale ofrecovered copper and zinc concentrates paid for allthe operating costs.

12:10 PMBiotechnology in the Mining and Metallurgical Indus-tries: Costs Savings through Selective Precipitation ofMetal Sulfides: H. Dijkman1; C. J. N. Buisman1; H. G.Bayer2; 1Paques Bio Systems B.V., P.O. Box 52, AB BalkNL-8560 The Netherlands; 2Kennecott Utah CopperCorporation, P.O. Box 112, Br ingham Canyon, UT84006-0112 USA The PAQUES Bio Systems’ core technology, mar-keted under the name THIOPAQ , consists of varioushigh-rate biological processes for metal-sulfur-watersystems, complemented with common solid/liquidand gas separation steps. Sulfur species are convertedto sulfide, which is a valuable component as it canbe used for metals reduction and precipitation. Se-lective recovery of valuable metals can be employed,leading to revenue from metal values. In this paper,

biotechnological systems for the treatment of metalsulfate solutions and dilute SO2 gases are described.These installations can be designed to either producepredominantly aqueous (NaHS) or gaseous (H2S) sul-fide. The emphasis here is on hydrogen sulfide gas.The main case history discussed is the demonstrationplant that ran on hydrogen gas at Kennecott UtahCopper. Three years of operating experience clearlyshow that sulfate reduction with hydrogen gas is aviable option. Furthermore, the selective recovery ofcopper from leach water with the hydrogen sulfideproduced was shown to be very effective.

Mineral Processing: Operations II

Tuesday AM Room: JeromeOctober 12, 1999 Location: Pointe Hilton Resort

Session Chairs: Scott Bird, Kennecott CopperCompany; Damon Fisbeck

10:30 AMA Simulator for Crushing - Screening Plants: GeorgeGrandy1; Cristian Araya2; 1Kvaerner Metals E&C, Dept.of Tech., 12657 Alcosta Blvd., San Ramon, CA 94583USA; 2Kvaerner-Metals E&C, Tech. Dept., Nva. Tajamar481, p.19, Santiago, Chile Kvaerner experience is being used to develop soft-ware to design or simulate crushing and screeningplants. The model techniques discussed are presentlybeing used for open-circuit plants and are being ex-tended to closed circuit plants. The program containsa library of routines, each representing a piece ofequipment or unit operation, which are assembledinto one of several open-circuit plant configurations.Routines include gyratory primary crushers; standardsecondary and shorthead tertiary cone crushers;single, double or triple deck screens; and stockpiles,feed bins and belt conveyors. The program usessteady-state models to simulate the performance ofcrushers and screens that have small residence timesand quickly reach equilibrium when operating con-ditions and/or parameters are changed. The dynamicaspect of the total circuit model concerns the stor-age units within the circuit, i.e. stockpiles and bins,and, in the closed circuit configuration, circulatingloads and size distributions. In many cases, justvendor’s catalog data are necessary for a pre-feasi-bility simulation; in other cases, actual plant test dataare required to obtain more accurate simulations. Theentire plant is shown in a single graphic screen so theuser can see all the relevant information he mightwant, and soft-keys are provided for the user to makeon-line parameter changes and observe the effectson storage elements, equipment feed rates and thefinal product size distributions. The model also reportsequipment utilization in percentage, power consump-tion, and other related operating information, andsoon, will be able to report estimated capital andoperating costs.

10:55 AMMagnetic Collection of Grinding Ball Fragments fromSAG and Ball Mill Circuits: Daniel A. Norrgran1;

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Michael J. Mankosa1; 1Eriez Manufacturing Com-pany, P.O. Box 10608, Erie, PA 16514-0608 USA Grinding ball fragments discharging from SAG millsand ball mills causes extreme wear to downstreamprocessing equipment. These ball fragments, recircu-lating in a milling circuit, will cause excessive wear tosumps, pumps, hydrocyclones, and interconnectingpiping. A magnetic separation system to removegrinding ball fragments from the mill discharge hasbeen developed and successfully applied in the mill-ing circuit. This magnetic separation system—termedTrommel Magnet—was first applied at the Escondidacopper concentrator in Chile. The Trommel Magnetconsists of an arc of permanent magnets mountedat the discharge end of the trommel screen. The mag-netic arc attracts the ball fragments and removesthem from the process stream. This retrofitted mag-netic separation system removed 126 metric tons ofball fragments from the circulating load of a singleball mill in the initial 24 hour period. The mill has sincestabilized and the magnetic separator is currently re-moving 7 metric tons per day of ball fragments. Theretrofit of the Trommel Magnet has: 1. Extended thepump life and the hydrocyclone life approximately300 percent; 2. Provided a 5 percent increase in thethroughput of the mills by removing grinding ball frag-ments that contribute very little to the grinding pro-cess. Variations of the Trommel Magnet have also beendeveloped for removing grinding ball fragments di-rectly from the mill discharge without the use of atrommel screen. In each case, permanent magnetsare used to collect the ball fragments from the milldischarge stream prior to reporting to the sump. Theseother systems have been designed and fabricatedfor in-plant test work.

11:20 AMMilling for the Millennium: Stuart M. Jones1; R. FredPena1; 1Svedala Industries, Inc., Grinding Div., 240Arch St., York, PA 17405 USA This paper describes the state of the art of grindingin the Copper Industry today including descriptionsof the largest equipment and design features whichallow processing of as much as 100,000 mtpd in asingle mill line. We include a typical flowsheet, con-trol philosophies, and maintenance techniques whichresult in low cost production which is essential intoday’s market.

11:45 AMMetal Seated Ball Valves for the Flow Control of Abra-sive Fluids: Malcolm J. Harrison1; 1Valvtechnologies,Inc., Mining & Minerals Processing, 5904 Bingle Rd.,Houston, TX 77092 USA The problems associated with the flow control ofabrasive slurries and solids laden fluids creates reli-ability problems in many mining operations. Conven-tional valves such as pinch, knife gate and plug typescannot always function reliably in such harsh operat-ing environments. Due to the technological advancesin the hard coating industry, ball valves can now beproduced with internal surfaces protected from theerosive effects of these applications. Pressures well inexcess of the capability of conventional 1000 kPaworking pressure valves can now be handled reliably.The significant advantages of minimizing down-timeand lowering maintenance costs can now be real-ized with metal seated ball valves.

12:10 PMNext Generation Sedimentation Equipment for UltimateThickening: Alex Probst1; Jim Bowersox1; 1Dorr-Oliver,Inc., 333 South Allison Pkwy., Suite 304, Denver, CO80226-4656 USA With low metal prices and increasing value placedon plant water and tailings disposal areas, it is be-coming essential to maximize the efficiency of solid-liquid separation processes. Since its inception over25 years ago, the use of flocculants has grown expo-nentially. While flocculants play a crucial role in thesedimentation process, they are also a major operat-ing cost. Recent innovations are revolutionizing theindustry once again. New thickener designs are dou-bling thickener-loading rates while reducing floccu-lant consumption. The feedwell, as the heart of thethickener, is undergoing many significant metamor-phoses. With CFD and other advanced computa-tional analysis, feedwell technology is being exam-ined more thoroughly than ever before. The result isthat the thickener previously thought of, as a “BlackBox” is now being mapped and controlled with state-of-the-art technology. This paper will examine recentdesign improvements in all aspects of thickeners inorder to project the look of the thickener of tomor-row.

Pyrometallurgy-Operations: Session III

Tuesday AM Room: EstrellaOctober 12, 1999 Location: Pointe Hilton Resort

Session Chair: Patricio Barrios, Atlantic Copper,Avda. Francisco Montenegro s/n, Huelva 21001Spain; G. A. Eltringham, BHP Copper Smelting andRefining, 200 South Redington Rd., P.O. Box M, SanManuel, AZ 85631 USA

10:30 AMCopper Metallurgy at the KGHM Polska Miedz S.A. -Present State and Perspectives: Józef Czernecki1;Zbigniew Smieszek1; Zdzislaw Miczkowski1; JerzyDobrzanski2; Marian Warmuz2; 1Institute of Non-Fer-rous Metals, ul.Sowinskiego 5, Gliwice 44-100 Poland;2KGHM Polska Miedz S.A., ul. M.C. Sklodowskiej 48,Lubin 59-301 Poland The Polish copper concentrates are characterisedby low content of sulphur and iron. At KGHM PolskaMiedz S.A. two copper production technologies arein use. The shaft furnace process is used at the LegnicaCopper Smelter and the Glogow I Copper Smelter. Asingle-stage direct to blister Outokumpu flash smelt-ing process is used at the Glogow II Copper Smelter.Melting copper concentrates in the shaft furnaces iscarried out in a reducing atmosphere and the prod-uct obtained is a matte. Instead, a result of meltingcopper concentrates by an oxidising flash processblister copper of a quality similar to that of convertercopper is obtained. The annual copper productionat KGHM Polska Miedz S.A. excedes 450,000 tons.Another important metal is silver produced from slimesfrom copper electrolysis (about 1000 t/y). Moreover,such metals as Pb, Ni, Se, As, Au and other precious

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metals, including Pt and Pd, are recovered from vari-ous semiproducts. This paper presents technologicalflow sheet of the copper production in plants usingthe shaft furnaces and in another plant in which asingle-stage flash process is applied. Characteristicsof products, methods of their utilisation, main param-eters of particular technological operations, andadvantages and shortcomings of the solution appliedare presented. There are also discussed the naturalenvironment protection as well as directions of theKGHM Polska Miedz S.A. plants modernisation.

10:55 AMBreaking New Ground - Recent Developments in theSmelting Practice at ZCCM Nkana Smelter, Kitwe,Zambia: Godwin Beene1; Enock Mponda1; MiltonSyamujulu1; 1Zambia Consolidated Copper Mines Lim-ited, Nkana Smelter, P.O. Box 22000, Kitwe, Zambia,Central Africa During recent years, copper and acid productionfrom Nkana Smelter has formed a significant propor-tion of ZCCM’s total output, but a number of prob-lems affecting the smelter over the last decade haveonly been recently overcome. This paper discussesrecent developments in the smelting practice, high-lighting some of the operational problems experi-enced and associated solutions. The smelter perfor-mance over the decade is discussed and the innova-tions in the smelting technology employed to sustainproduction in the wake of limited re-capitalizationare dealt with in detail.

11:20 AMCompetitiveness of the Outokumpu Flash SmeltingTechnology - Now and in the Third Millennium: P.Hanniala1; L. Helle1; I. V. Kojo1; 1Outokumpu Engineer-ing Contractors Oy, P.O. Box 862, Espoo FIN 02201Finland In the day-to-day life the copper business of todayis influenced directly by the ever-increasing generalconcern about the environment. In addition to thatthe inherent shortcomings of the copper smelting busi-ness, have since many years been the falling real pricelevel of the metals and the relatively high initial capi-tal investments required for the production units. Theseshortcomings have been compensated for by highproductivity, low specific operating costs, low metalinventory and unbeatable technological superiority.Thus today more than 50% of the world primary cop-per is today produced by utilizing Outokumpu FlashSmelting Technology. This figure is expected to growat an increasing speed in the near future. Character-istic for the Outokumpu Flash Smelting technology ishigh flexibility for a wide grade of concentrates andthe highest sulfur capture owing to at the same timecompetitive investment and operational costs. TheFlash Converting technology offers new options forcopper production and optimization of the mine-con-centrator-smelter production chain. In the followingyears it is expected that the trend in copper making isthat higher grade concentrates are produced at themines. Thus increasing amount of high grade con-centrate will be available for direct-to-blister FlashSmelting causing an overall cost reduction in coppersmelting i.e. both in capital and operational costs. Inthe 90’s new technologies based on Outokumpu FlashSmelting technology have been taken into operation,thus eliminating the noncontiguous Peirce-Smith con-

verting process step. New innovative solutions havebeen used in the latest projects, as in Kennecott UtahCopper, where the new Kennecott-Outokumpu FlashConverting process was started up in 1995. Also, in1995 the new DON process was started at OutokumpuHarjavalta nickel smelter followed by the Fortalezanickel smelter in Brazil in 1997. The aim of the continu-ous development work at Outokumpu has been theexpansion of the direct-to-blister process towardslower grade concentrates. The most recent exampleof this is the start-up at the Olympic Dam smelter inAustralia, where the existing direct-to-blister FlashSmelting furnace was replaced with a new one hav-ing a capacity of 200 000 t blister copper per annumin just one smelting step.

11:45 AMDevelopments in Direct-to-Blister-Smelting at OlympicDam: Arthur G. Hunt1; Steven K. Day1; Rosalind G.Shaw1; Robert C. West1; 1WMC Resources Limited,Olympic Dam Operations, P.O. Box 150, Roxby Downs5725 S. Australia Smelting using the direct-to-blister process com-menced at Olympic Dam on July 31, 1988. The uniquenature of the Olympic Dam ore body led to the se-lection of the direct to blister smelting process. Signifi-cant improvement in the design of the furnace andthe understanding of the fundamentals of the pro-cess and its operation has occurred in the 10 years ofoperation. The paper will discuss the operation of the#1 Smelter and the design, preparation for start upand early operating experience of the #2 Smelter.

12:10 PMExpansion of Onsan Smelter: J. H. Lee1; S. W. Kang1;H. Y. Cho1; J. J. Lee1; 1LG Metals Corporation, OnsanPlant, 70 Daejung-Ri, Onsan-Eup, Ulju-Kun, Ulsan 689-890 Korea LG Metals Corporation started its 2nd smelter op-eration at Onsan along with the existing flash smelteron January 31, 1998. Onsan smelter has been pro-ducing about 140,000 tons of copper from concen-trates with the flash smelting line since 1979. In accor-dance with an increase in domestic copper demand,LG Metals Corporation decided to expand smeltingand refining capacity by introducing 2nd smelter lineusing the Mitsubishi continuous process and a newtankhouse in 1995. After two years’ expansion worksconsisting of engineering, procurement, constructionand a successful commissioning test, the total smelt-ing capacity of Onsan smelter increased to 340,000tons of copper from concentrates. This paper de-scribes the smelting facilities, operation result, prob-lems encountered and improvements during the start-up and early operation of Onsan’s new smelter.

12:35 PMFirst Year of Operation of the Noranda ContinuousConverter: Y. Prévost1; R. Lapointe1; C. A. Levac1; D.Beaudoin2; 1Noranda, Inc., Horne Smelter, P.O. Box4000, Rouyn-Noranda, Québec, Canada J9X5B6;2Noranda, Inc., Technology Center, 240 Hymus Blvd.,Pointe-Claire, Québec, Canada H9R 1G5 The Noranda Continuous Converting Process wascommissioned in November 1997 at the Horne Smelterat Rouyn-Noranda, Québec, Canada. It has com-pleted over 18 months of successful operation. Excel-lent team work and technical expertise contributed

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to achieve targeted production levels and environ-mental goals after only a few months of operation.The operating results have demonstrated the flexibil-ity of the process in producing blister copper from avariety of copper feed materials including a combi-nation of molten and solid copper matte, reverts andfluxes. This paper describes the startup activities andprocess optimization tasks performed during the firstyear of operation of the new Noranda Converter.

Smelting: Technology Development, Pro-cess Modeling and Fundamentals: ProcessModeling and Control I

Tuesday AM Room: GoldwaterOctober 12, 1999 Location: Pointe Hilton Resort

Session Chairs: Carlos Landolt, Inco Limited, OntarioDivision, Sudbury, Ontario, Canada; LarrySouthwick, L. M. Southwick & Associates, 992Marion Ave., Suite 306, Cincinnati, OH 45229 USA

10:30 AMReal Time Data Management to Improve Productivityof Mining & Metallurgical Operations: O. A. Bascur1;J. Patrick Kennedy2; 1OSI Software, Inc., Houston, TXUSA; 2OSI Software, Inc., San Leandro, CA USA Applying the latest information technologies inmining and metallurgical complexes has become aserious challenge to management and technicalteams. Emerging component design is changing theway the user relates to the desktop. Connectivity be-tween mining and metallurgical process operationsand their business systems has become a reality. Ex-panded use of plant information on the desktop is astandard tool for revenue improvement, cost reduc-tion and adherence to production constraints. Theindustrial component desktop support access to in-formation for continuous improvement and innova-tion by staff personnel and engineers. Collaborationbetween groups enables the implementation of anoverall process effectiveness index based on lossesdue to equipment availability, production recoveryand quality rate. The integration of information frommining, mineral processing and metallurgical perfor-mance monitoring increases production efficiency,even when many elements cannot be measured di-rectly. Three case studies of large mining/metallurgi-cal complexes are highlighted.

10:55 AMDatabases and Software for Thermodynamic Simula-tion of Copper Smelting and Converting: Sergei A.Degterov1; Arthur D. Pelton1; Manuel Zamalloa2; 1ÉcolePolytechnique de Montréal, Ctr. de Recherche enCalcul Thermochimique, C.P. 6079, Station Centreville,Montréal, Québec, Canada H3C 3A7; 2NorandaTechnology Center, 240 Hymus Blvd., Pointe-Claire,Québec, Canada H9R 1G5 A thermodynamic database for the slag, matteand liquid copper phases in the Cu-Ca-Fe-Pb-Zn-Si-O-S system has been developed for the ranges ofcompositions of importance to the production of

copper. When used with the Gibbs energy minimiza-tion software and other databases of the F*A*C*T ther-modynamic computing system, this database willpermit the calculation of matte-slag-copper-gasphase equilibria that take place during copper smelt-ing and converting. The calculations reproduce withinexperimental error limits all available experimentaldata on phase diagrams, activities of components,enthalpies of mixing, matte - alloy miscibility gap andtie-lines. The calculated solubilities of Cu in both S-free slag and slag equilibrated with matte are also ingood agreement with experiment under all studiedconditions, such as at Si02 saturation, in equilibriumwith Fe, Cu or Cu-Au alloys, at fixed oxygen or S02partial pressures and at different contents of Pb, Znand CaO in the slag. Sulfide contents (sulfide capaci-ties) of the slags are predicted within experimentalerror limits. The distribution of Pb and Zn among matte,slag, copper and gas has been calculated. The cal-culations are in good agreement with experimentaldata and predict the distributions under conditionswhich are difficult to study experimentally, such as atmagnetite saturation or under various oxygen partialpressures and iron to silica ratios in the slag.

11:20 AMThermochemical Modeling of Smelting Operations:Alastair L. Davies1; John F. Castle1; Philip J. Gabb1;Marielle A. S. Siraa1; John A. Gisby2; A. J. Weddick3;1Rio Tinto Technical Services, P.O. Box 50, Lower CastleSt., Castlemead, Bristol BS99 7YR UK; 2National Physi-cal Laboratory, Centre for Mats. Measure. and Me-trology, Queens Rd., Teddington, Middlesex TW11 0LWUK; 3Kennecott Utah Copper Smelter, 12000 West 2100South, Magna, UT 84011 USA The MTDATA computer software package consistsof a rigorous implementation of an algorithm for cal-culating chemical phase equilibria by the techniqueof Gibbs free energy minimization and a databaseof the thermochemical properties of common mate-rials, such as slags, mattes, metals, gases and aque-ous solutions. We have used MTDATA to contribute toour understanding of the chemical reactions occur-ring in several specific unit operations of the KennecottUtah Copper Garfield Smelter. The following two ex-amples illustrate the range of environments to whichthe method is applicable. Calculation of the liquidusphase relations of the FSF fayalite and FCF calciumferrite slags helped in the early diagnosis of severaloperating problems. Calculation of the deportmentof fluorine between the FSF offgas and the FSG scrub-ber liquor helped in the identification of operatingconditions under which significant hydrogen fluorideconcentrations could be introduced to the contactsection of the acid plant. Without the painstaking as-sessment of solution phase properties undertaken overmany years, these calculations would not be possible.

11:45 AMProcess Modeling for KUCC Smelter Studies and On-Line Furnace Control: Marielle A. S. Siraa1; Alastair L.Davies1; Philip J. Gabb1; A. J. Weddick2; 1Rio TintoTechnical Services, P.O. Box 50, Lower Castle St.,Castlemead, Bristol BS99 7YR UK; 2Kennecott UtahCopper, Smelter, 12000 West 2100 South, Magna, UT84044 USA A program of work was undertaken at theKennecott Smelter and Refinery to model the com-

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plex. This effort contributed a total of eight models ofthe plant: flash smelting furnace, flash converting fur-nace, slag concentrator, anode furnace, offgasscrubbing system, acid plant, hydrometallurgical dusttreatment plant, and the precious metals plant. Someof these models have been used in a variety of inves-tigations ranging from offgas capacities for a steamgeneration analysis to an examination of impurities.The culmination of this enterprise has resulted in anon-line control scheme for the flash smelting and flashconverting furnaces. These two process controlschemes incorporate their respective steady-state heatand mass balances that are executed in response tofeed changes while a feedback loop calculates whenproduct grade and temperatures deviate fromsetpoints. This system has been put into place to im-prove furnace control and on-line time.

12:10 PMQuantification of the Dynamics of the Flash Smelter:I. H. Bonekamp1; J. H. Groeneveld1; M. A. Reuter1; G.Gopos2; P. Kuhn2; A. Lossin2; P. Willbrandt2; 1Delft Uni-versity of Technology, Dept. of Raw Mats. Proc.,Mijnbouwstraat 120, Delft 2628 RX The Netherlands;2Norddeutsche Affinerie Aktiengesellschaft, Hovest-rasse 50, Hamburg D-20539 Germany Norddeutsche Affinerie has operated anOutokumpu type flash smelter for more than 25 years.In recent years, the concentrate smelting capacitywas increased to 750,000 tpy, double of the initialdesign capacity. Maintaining this high performancelevel requires very good metallurgical process con-trol. It is not enough to base this control on thermo-dynamics and kinetics since the furnace is highly dy-namic. Understanding these dynamics and beingable to quantify them can have significant financialbenefits. A mass and energy balance model was de-veloped and is discussed based on measured data.At this time the model is based on the major elementscopper, iron, sulfur and silica. With it is possible toquantify the differences of the various material streamssuch as matte, slag, flue dust, matte carry-over to set-tling furnace, etc. Comparing the reconciled energybalance model with the fundamental thermodynamicmodel makes it possible to quantify the dynamics.These dynamics are related to input parameters us-ing methods such as statistics and neural nets. In thefuture this database will be used to improve the un-derstanding of the dynamic process as well as thedynamic process control.

12:35 PMSoftware for the Analysis of Flash Smelting Data:Serban Motoiu1; 1Institute for Nonferrous and RareMetals, Heavy Metals Lab., 102 Biruintei Blvd., Bucha-rest 73856 Romania Data acquisition is widely used for controlling flashsmelting furnaces. A Romanian smelter from which alarge amount of data can be collected uses such atechnique. A computer program was developed forinterpretation of the data. Inputs to the program arethe process data files. Abnormal data are identifiedusing standard statistical techniques; they can beedited if necessary. The following methods can beused for the analysis: linear correlation (single or mul-tiple), polynomial correlation or comparison of twoaverage values. Time variation graphs and histo-grams can be displayed. The random balance

method was used for determination of significantparameters influencing the process performance. Notall process parameters are recorded, and some ofthem are not even measured. The software can com-pute some of these parameters such as: air flow raterequired and the oxygen content of the gas exitingthe reaction tower. The software was used for the in-terpretation of a large amount of process data. Theanalysis showed that the process did not operateproperly at some times.

Smelting: Technology Development,Process Modeling and Fundamentals:Gas Handling

Tuesday AM Room: FlagstaffOctober 12, 1999 Location: Pointe Hilton Resort

Session Chair: Carlos Diaz, University of Toronto, c/oDept. of Metallurgy and Matls. Sci., Toronto,Ontario, Canada

10:30 AMOptimization of Smelter Off-Gas Handling System: B.C. Curson1; A. A. Shook1; 1BHP Copper Smelting andRefining, 200 South Redington Rd., P.O. Box M, SanManuel, AZ 85631 USA A comprehensive simulation of the gas handlingsystem in BHP Copper’s San Manuel smelter was de-veloped using AFT Fathom software, with the objec-tive of minimizing S02 emissions while maximizingsmelter throughput. Once verified with plant data, thesimulation quickly revealed the complex interactionsoccurring between individual converters and the flashfurnace. The increased understanding provided bythe simulation allowed novel, counter-intuitive con-trol strategies to be developed and tested success-fully.

10:55 AMComparative Productivity and Quality Evaluation ofCopper Smelting Gas Cooling Techniques: ReneBustamante1; Jaime Fernandez1; 1Universidad deSantiago de Chile, Depto. Ingenieria Metalúrgica, P.O.Box 10233, Santiago, Chile The subject of this paper is a comparative evalua-tion of different copper smelting gas cooling tech-niques, using “productivity and quality” criteria. Thefirst section presents a brief description of the opera-tion of the radiant and the evaporative cooling sys-tems, focusing on the differences between each other,in particular regarding: a) mass and energy balances;b) gas flow, temperature and composition; c) dustconcentration and recovery. This section includes abrief discussion of the “client-server chain,” i.e. thelinks between the cooling equipment and the down-and up-stream operations. More in particular, the up-stream server relationship impacts on the operatingstability of the furnace, and in turn on furnace down-time and Cu production losses; and the down-streamclient relationship affects the operation of the elec-trostatic precipitators, in terms of workload and costof handling larger quantities of dust of a given dust

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size. The second section deals with the developmentof indexes to measure and compare value addedthrough the “utilization, productivity and quality” thatcan be expected of both cooling methods at thephysical and economic levels, and the impact onthe overall smelter productivity and the final cost com-position of copper. The final section presents the re-sults and includes a discussion of the comparativeadvantages and disadvantages of both cooling sys-tems.

11:20 AMAlkaline Arsenic Leaching from Smelter Flue Dust andLeaching Solution Regeneration: Antelmo V. Robles1;Ana E. Serna1; Manuel A. Sández1; 1Mexicana deCobre, S.A. de C.V.; Complejo Metalúrgico, Dept.de Investigación y Nuevos Procesos, Carr. Nacozari-Agua Prieta Km 21.5, Nacozari, Sonora 84340 México The main goal of the present work is to propose aviable alternative for selective arsenic elimination fromcopper smelter flue dust without the need of a glo-bal leaching scheme for all the individual compo-nents of the flue dust. Using this alternative, the inher-ent copper recovery problems are avoided. Arsenicprecipitation is also considered for regenerating thesolution and completing the process cycle. The ex-perimental results for arsenic extraction and precipi-tation are satisfactory. Concentration of NaOH usedwas relatively low. The main reason for succeedingin high arsenic extraction and low NaOH consump-tion is due to the previous water washing of the fluedust. Water washing dissolves much of the iron andcopper that are present in certain percentage as sul-phate.

Copper Applications and Fabrication:Applications - I

Tuesday PM Room: CopperOctober 12, 1999 Location: Pointe Hilton Resort

Session Chairs: K. Kundig, Metallurgical Consultant,2 School House Rd., Randolph, NJ 07869 USA;H. Larravide, PROCOBRE-Chile, Santo Domingo 551,2° Piso, Santiago, Chile

2:00 PMThe Copper Motor Rotor and Plastic Injection Molds -New Developments Relying on Copper’s Conductiv-ity: Dale T. Peters1; John G. Cowie1; 1Copper Devel-opment Association, Inc., 260 Madison Ave., 16thFloor, New York, NY 10016 USA Conductivity, both electrical and thermal, are at-tributes accounting for about 70% of the applicationsof copper and its alloys. This paper presents results ofon-going research into two new applications thatdepend on copper’s excellent conductivity. The Cop-per Development Association (CDA), together withmaterials and motor company partners, is workingtoward a solution to the key problem preventing pres-sure die casting copper for the conductor bar/endring structure of the induction motor rotor, i.e., lackof a durable high-temperature mold material. Work

is showing that a combination of high-temperaturematerials and elevated temperature processing givesmuch improved mold life compared to die steels.Substitution of copper for aluminum in the rotor canresult in a 20% decrease in electrical losses in motorsconsuming 35% of electrical power generated in theU.S. The second development uses the excellent ther-mal conductivity of several high-strength high-cop-per alloys to simultaneously improve productivity andpart quality in the injection molding of plastic parts.

2:25 PMA Review of Bismuth and Selenium Modified CopperAlloys for Plumbing Applications: M. Sahoo1; L. V.Whiting1; M. Sadayappan1; D. T. Peters2; 1CANMET,Mats. Tech. Lab., 568 Booth St., Ottawa, Ontario,Canada K1A OG1; 2Copper Development Associa-tion, 260 Madison Ave., New York, NY 10016 USA The development of new alloys containing bismuthand selenium for potable water supplies are reviewed.The new alloys are replacements for the leaded red -and semi-red brasses by the low-lead alloys. SeBiLOYSI and II, for sand casting, and SeBiLOY III replaces thelead containing yellow brass, C85800, for permanentmold casting. As the new alloys use bismuth and se-lenium, the supply and demand of these elementsare discussed. The key casting characteristics dis-cussed are: tendency to dross formation, freezingrange (liquidus and solidus temperatures), fluidity, re-sistance to hot tearing, microstructures, mechanicalproperties, machinability, grain refinement and cor-rosion behaviour.

2:50 PMInfluence of Environment on the Copper Patinas: M.A. Llavona1; A. M. Fernández1; J. L. Ibáñez1; R.Zapico1; 1University of Oviedo, Dept. of Mats. Sci.,U.S. of Mining and Topographic Eng., Reinerio Garcias/n, Mieres 33600 Spain The study of the formation and components ofcopper patina and its conservation has assumedgreat importance. The changing environment hasaccelerated the processes of patinas degradation;thus, the exhaustive study of factors capable of af-fecting the patina formation, growth and durabilityhas assumed great importance for the industrial ac-tivity of copper. The main components of the patina,oxides, chlorides, nitrates and sulfates, have beendetermined; the effect of physical, chemical and mi-crobiological factors on patina formation, particu-larly the influence of acid rain, natural organic mat-ter, particles and microorganisms have been defined.The effect of different electrolytic solutions that ac-celerate the formation of copper patinas has beendetermined, and a review of the state of knowledgeof the formation and evolution of metal patinas hasbeen made.

3:15 PMCopper for Long-Term Isolation of High Level NuclearWaste: Lars O. Werme1; 1Swedish Nuclear Fuel andWaste Management Company (SKB), P.O. Box 5864,Stockholm SE-102 40 Sweden Already the KBS Project proposed copper as a suit-able material for encapsulation of spent nuclear fuel.The basis for this choice was the thermodynamic sta-bility of copper in water and the fact that deep gra-nitic groundwaters in Sweden are oxygen-free. Witha limited supply of oxidants, a copper canister would

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have the potential for a very long service life. Theresearch and development work aiming at encapsu-lating nuclear fuel entered a new phase in 1993, whenSKB launched its Encapsulation Plant Project. Withinthis project, SKB has: designed a facility for encapsu-lation of nuclear fuel; laid down the design premisesfor a canister for disposal of nuclear fuel; tested anddeveloped fabrication methods for copper canisters;evaluated the long term chemical and mechanicalbehavior of the canister; made preliminary plans fora factory for the production of copper canister; con-structed a canister laboratory for full scale testing ofthe key operations in an encapsulation plant. The con-clusions of this project were that a canister consistingof an outer layer (50 mm) of copper over an insert ofcast nodular iron would provide sufficient corrosionprotection and would have sufficient mechanicalstrength. This canister can be produced by severalmethods of which forming from rolled plates, hot ex-trusion, and “pierce and draw” have been tested atfull scale. The canister will be sealed by electron beamwelding in the encapsulation plant, and the integrityof the weld will be verified by ultrasonic testing andhigh-energy radiography. The final development workin this area will be performed in the canister labora-tory.

3:40 PM Break

4:10 PMStudy of the Effect of Sulfide Ions on the CorrosionResistance of Copper for use in Containers for High-Level Waste: I. S. Escobar1; E. Silva1; C. Silva1; A. Ubal1;1Comisión Chilena de Energia Nuclear, AmunateguiN° 95, Santiago, Chile Copper, particularly the oxygen-free grade Cu-OFP,is a candidate material for containers for the long-term isolation and disposal of high-level radioactivewaste (HLW) in underground repositories. After hav-ing been buried for a few hundred years, all oxygenwill have been consumed in the repository, and cor-rosion of the copper will be caused entirely by con-tact with dissolved sulfides. Chloride is another po-tential corrodant, but in deep repositories wheregroundwater is neutral or slightly alkaline, the effectof chlorides can be ignored on thermodynamicgrounds. Thus, the corrosion of copper in the pres-ence of sulfide ion and under reducing conditionshas been studied using cyclic voltammetry and Tafelslope measurements. It is possible to determine theeffect of sulfide ion on copper corrosion resistancewhich is minimized at low temperature and also atlow sulfide concentration. The presence of anionssuch as HCO3—under environmental conditions—pro-duces a beneficial effect because these ions are in-hibitors.

4:35 PMA Spanish-Language Copper Information Database:Helga Larravide1; Konrad J. A. Kundig2; 1Procobre-Chile, Metallurgical Consultant, Santo Domingo 551,2° Piso, Santiago, Chile; 2Metallurgical Consultant, 2School House Rd., Randolph, NJ 07869 USA A new on-line database of literature about cop-per has been created through a joint undertaking bythe Copper Development Association, Inc. andPROCOBRE-Chile, with funding provided in part bythe International Copper Association, Ltd. The new

database will permit Spanish-speaking technologiststo access publications maintained by PROCOBRE-Chile by means of standard keyword searches. Inaddition, a new Spanish-English thesaurus has beenwritten to enable Spanish-speaking individuals tosearch and access the Technology and Environmen-tal databases of the Copper Data Center, which to-gether comprise more than 80,000 publications deal-ing with the production, properties, uses and envi-ronmental effects of copper. Planned expansion ofthe new Spanish literature database is described.

5:00 PMCopper Industry Response to an Environmental At-tack on Copper Plumbing Tube: Dale T. Peters1; Will-iam H. Dresher2; 1Copper Development Association,Inc., 260 Madison Avenue, New York, NY 10016 USA;2WHD Consulting, 1201 E. Placita Ardilla, Tuscon, AZ85718 USA In the United States, the United Kingdom and nu-merous other countries, copper has long been theplumbing material of choice. This has been the casesince the late 1920's in the United States and sinceWorld War II in the United Kingdom. However, in re-cent years the plumbing tube market has caught theeye of the chemical industry and several plastic res-ins have been introduced to the marketplace as sub-stitutes for copper in household plumbing systems.One of these, polybutylene tube, had so many fail-ures in the United States that a class action law suitwas filed, and the manufactures of this product wereforced to create a trust fund of nearly one billiondollars to repair damages caused by their product.Chlorinated polyviny-lchloride (CPVC), in rigid pipeform, on the other hand, has been mechanicallyacceptable albeit its recent introduction precludesthe test of time enjoyed by copper tube in this appli-cation. This paper reviews the State of California’sportrayal of copper’s environmental effects and willbe largely based on the data and information as-sembled by the Copper Development Association,Inc. in its presentation to the State of California inAugust, 1998 in response to the State’s Draft Environ-mental Impact Report for Chlorinated Polyvinyl Chlo-ride (CVPC) Pipe for Use for Potable Water Piping inResidential Buildings. The paper is intended to be usedas a model for the use of other copper organizationsand individuals in responding to similar situations.

5:25 PMCopper Electrodes for Resistance Spot Welding of Alu-minum: B. Fresz1; J. R. Groza1; S. Stefensen1; 1Univer-sity of California at Davis, Dept. of Chem. Eng. andMatls. Sci., Davis, CA 95616 USA Before aluminum can be utilized in automotivebodies, the longevity of the electrodes employed inthe resistance spot welding of aluminum must in-crease. This paper explores the affects of electrodecomposition on electrode life. To compare these vari-ables, electrode tests were completed on a TaylorWinfield welding machine using, Cu-Cr, Cu-Zr, Cu-Cr-Zr, Cu-Be, and Glidcop® electrodes tested to 12.5%,25%, 50%, 100% and 150% lifetimes. Electrode diam-eters were determined via a magnification techniqueusing a PULNIIX video camera attached to a lowmagnification Wild Heerbrugg stereo-zoom micro-scope. From these measurements, graphs of electrodelife versus face diameter and weld number versus face

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diameter were created. Analyses of these graphs sug-gest that a single failure mechanism is responsible forelectrode failure, though the number of welds untilfailure (100% electrode life) varied with composition(700-2000 welds).

5:50 PMProgress Report on Development of a Cu-8 Cr-4 NbAlloy Database for the Reusable Launch Vehicle (RLV):David Ellis1; Hee Man Yun2; 1Case Western ReserveUniversity, 10900 Euclid Ave., Cleveland, OH 44106-7204 USA; 2Cleveland State University, 1983 East 24thSt., Cleveland, OH 44115 USA The next generation of Reusable Launch Vehicle(RLV) will utilize regeneratively cooled combustionchamber liners in the engines. The current design callsfor using a new Cu-8 at.% Cr-4 at.% Nb (Cu-8 Cr-4Nb) alloy for the liners. Work is ongoing to character-ize the thermophysical and mechanical properties ofthe alloy from 253 to 800°C, the temperature rangeto which the alloy will be subjected to during service.The alloy has been commercially produced in quan-tity for NASA. The powder size has been character-ized and the microstructure examined. The powderwas extruded into bar using a commercial extrusionpress. In addition, samples have been hot isostaticallypressed (HIPed) at NASA Glenn Research Center. Bothprocessing methods produced fully consolidatedmaterial. Transmission electron microscopy (TEM) re-vealed highly faulted Cr2Nb and some elemental pre-cipitates. Cryogenic tensile testing showed the ex-truded specimens had significantly higher strengthsthan NARloy-Z (Cu-3 wt.% Ag-0.5 wt.% Zr) even afterbeing subjected to a simulated braze cycle. TheYoung’s moduli (Cu-8 Cr-4 Nb) were lower thanNARloy-Z. The lower moduli is highly beneficial forreducing thermally induced stresses in rocket enginecombustion chamber liners and similar applications.

Electrorefining: Refinery Operations IV

Tuesday PM Room: IndigoOctober 12, 1999 Location: Pointe Hilton Resort

Session Chairs: R. D. Hutcheson, Southwire Com-pany, Copper Division, Carrollton, GA 30117 USA;R. Sanford, Kennecott Utah Copper, Refinery Plant,Magna, UT 84044 USA

2:00 PMA New Starting Sheet Plant at the Toyo Copper Refin-ery and Productivity Improvements: O. Nakai1; H.Sato1; K. Kugiyama1; K. Baba1; 1Sumitomo Metal Min-ing Company, Ltd., Toyo Smelter and Refinery, Besshi-Niihama District Div., Otu 145-1, Funaya, Saijyo, Ehime,Japan In the copper electrorefining process, the qualityof the starting sheet is one of the basic factors forproducing high quality copper cathodes. A highlyautomated and advanced facility for the productionof copper starting sheets was constructed at the ToyoCopper Refinery in 1992, bringing various improve-ments into an automatic stripping system using stain-less steel mother blanks. In 1998, the refinery expanded

the tankhouse by another 128 commercial cells, andintroduced 64 polymer concrete cells in a first stageconversion. As a result, the Toyo Copper Refinery nowhas the capacity to produce 103,200 t/y of cathodecopper. Construction has led to great improvementsin the materials handling facilities and computer as-sociated short-circuit detection technology. This re-port summarizes the improvements made in the qual-ity of the cathodes and in plant productivity.

2:25 PMImprovements in the Operating Practices at the At-lantic Copper Refinery: P. Barrios1; A. Alonso1; C.Ortiz1; 1Atlantic Copper, S.A., Avda. FranciscoMontenegro s/n, Huelva 21001 Spain The copper refinery of Atlantic Copper wasmodernised and converted to the ISA permanentcathodes system in 1995. The technology installed hasproved to be an excellent platform for the develop-ment of operational improvement. During the yearsit has been working, a progressive assimilation of thenew technology has been achieved and the level ofoperator knowledge has allowed design productionto be reached and surpassed by more than 10%. Atthe same time, modifications to work programmesusing existing equipment, have permitted the incor-poration of new cells and the achievement of an-nual production levels of 250,000 tonnes and produc-tivity of 0.43 t/man-hour.

2:50 PMKidd Process Permanent Cathode Technology Ad-vancements: P. E. Donaldson1; P. J. Murphy1; 1Falco-nbridge Limited, Kidd Creek Business DevelopmentGroup, Kidd Creek Metallurgical Division, Timmins,Ontario, Canada P4N 7K1 Since 1992, Falconbridge has made available tothe international copper industry, Kidd Creek’s li-censed refinery process technology under the nameof the Kidd Process. This has resulted in the supplyand installation of permanent cathodes and associ-ated product handling equipment to refineries inCanada, the United States, South Korea, Chile andMexico. These installations accommodate bothelectrorefining and electrowinning process. Thegrowth and industrial acceptance of the Kidd Pro-cess has generated technical advancements in theareas of product random sampling, corrugation,marking, labeling, product tracking and data acqui-sition. In a different area, the expanded developmentof custom materials processing at Kidd created a needto advance technologically. The process-relatedproblem of high nickel concentrations in refinery elec-trolyte comprised an increase in current density to>300 A/m2. The need for nickel removal resulted inKidd Creek’s newly developed Nickel Recovery Sys-tem. The effective and economical extraction ofnickel, along with reduced antimony and bismuthlevels, reduces bleed stream volumes and/or neutral-ization costs and simultaneously produces a market-able nickel carbonate product.

3:15 PMTeams that Work-Following the Gorilla’s Lead: J. W.Holzenthaler1; M. E. Yarish1; 1Phelps Dodge MiningCompany, El Paso Operations, P.O. Box 20001, El Paso,TX 79998 USA Teams continue to play a major role at the PhelpsDodge Mining Company El Paso Operations, espe-

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cially during the present time of low copper prices.The El Paso Operations’ teams have taken the initia-tive during this copper market downturn and havehelped reduce operating costs significantly. Becauseof this, Phelps Dodge El Paso Operations has contin-ued to grow within the team process by creating atotal, non-exempt salaried workforce. In the last yearalone, the El Paso Operations have implemented threemajor initiatives to accommodate the team process.The first was the creation of “Guiding Principles”, apolicies and procedures handbook. Second was the“zero and beyond” safety initiative. Third was teamcompensation. In addition, the Copper ProductsCompany has now adopted a work-team environ-ment, following in the lead of the refinery.

3:40 PM Break

4:10 PMStudies on Copper Electrorefining by Factorial DesignMethods - A Pilot Plant Experience: E. M. Alcântara1;1Caraiba Metais S.A., Via do Cobre n° 3700, A.I.O. -COPEC, Dias D’Ávila, Bahia, Brasil This paper describes some aspects about the rela-tionship between copper electrorefining addition re-agents and the hydrogen in the cathode. The condi-tions of electrorefining were studied by factorial de-sign methods. The advantages of this technique arereduction in the number of tests, well organized ex-periments, improvement in productivity and reliabil-ity of results. The dosage of the two main additionagents, glue and thiourea, were varied simultaneouslyand compared with the hydrogen content in thecathode. The influence of these factors, as well theirinteractions, were analyzed by statistical methodsdenominated ANOVA (Analysis of Variance). The in-crease of thiourea quantities, within of levels studied,influenced significantly at 95% confidence in the hy-drogen content in copper cathode.

4:35 PMEffect of Forced Convection of the Electrolyte on Cop-per Electrorefining in the Presence of Impurities: T.Takasu1; F. Noguchi1; H. Itou1; T. Nakamura2; 1KyushuInstitute of Technology, Dept. of Mats. Sci. and Eng.,1-1 Sensui, Tobata, Kitakyushu 804-8550 Japan;2Tohoku University, Institute of Advanced Mats. Proc.,Research Center Metallur. Process Eng., 2-1-1 Katahira,Aoba, Sendai 980-8577 Japan Overall productivity in copper refining is currentlydetermined by the electrorefining process. Previousresearch showed that forced convection of the elec-trolyte improves the morphology of the copper de-posit on the cathode and suppresses passivation ofthe anode. In this paper, electrorefining experimentsunder forced convection were carried out in the pres-ence of As, Sb and Bi impurities, both in electrolyteand in the anode, to determine the effect of the im-purities on the electrorefining process. The concen-trations of the impurities in the deposit increased withincreasing current density without forced convection.An increase in the fluid velocity suppressed the in-crease in impurity concentration. These concentra-tions were high, especially in the initial stage of depo-sition without forced convection, corresponding to adecrease in the cathode potential measured duringthat period. This indicates that the enrichment of im-purities was induced electrochemically. The reasonfor the decrease in cathode potential was the low

concentration of copper ions on the electrode sur-face because of ion consumption by the electrolysis.The forced convection of the electrolyte enhancedthe ionic mass transfer and thus suppressed the po-larization and deposition of the impurities. The fluidmotion was shown to be effective in achieving elec-trolysis under high current density conditions.

5:00 PMElectrochemical Processing of Speiss: V. A. Luganov1;E. N. Sajin1; T. V. Chnyrenkova1; 1Kazak National Tech-nical University, Almatry 480013 ROKazakstan During the treatment of raw materials containingarsenic and antimony, problems in the distribution ofthese elements in the process products occur. In anumber of cases in processing of copper-bearingmaterials, it is possible (or necessary) to obtain speiss.The purpose of the present research is to study thetheoretical aspects and analyze the technologicalpossibilities of producing copper- bearing speiss andthe subsequent electrometallurgical processing withcopper extraction as well as arsenic and antimonyutilization. Copper arsenide (Cu3As) and copper an-timonide (Cu3Sb) are the main components of thespeiss. A thermodynamic analysis of the electrochemi-cal oxidation of Cu3As and Cu3Sb, carried out usingPourbaix diagrams, showed that in a pH range from0 to 2, oxidation potential 0.45-0.55V, ions of copperand arsenic and antimony trioxide are in the equilib-rium. The kinetic study has shown, that with an in-crease in the polarization potential, the dissolutionprocess changes from chemical to diffusion control.An increase in temperature stabilizes the electrolysisprocess due to dissolution of arsenic trioxide formingon the anode. Electrolysis of speiss using a cathodediaphragm with the solution pH = 1-2, current density150-200 A/m2 and temperature 60-70°C makes it pos-sible to obtain cathode copper with a current effi-ciency of 95-96% and to remove the arsenic from theprocess during the electrolyte cleaning process. Thearsenic content in the cathode copper did not sur-pass 0.002%. As the result of the research, a techno-logical flowsheet for copper-lead speiss processingwas developed. At the present time this technologyis undergoing pilot testing.

Hydrometallurgy: Metal Extraction

Tuesday PM Room: HopiOctober 12, 1999 Location: Pointe Hilton Resort

Session Chairs: Albert Liguori, Oxidor, Dallas, TXUSA; Sergio Bustos, Lake Research, Chile S.A.

2:00 PMCopper Solvent Extraction Oxime Selectivity: Opera-tional Experience at Girilambone Copper Company:Kym A. Dudley1; A. S. Moroney1; M.O. Braaksma1; D.J. Readett2; 1Girilambone Copper Company, Boora-mugga Rd., Girilambone NSW 2831 Australia; 2StraitsMining Limited, Level 3 Gold Fields House, 1 Alfred St.,Sydney NSW 2000 Australia Basic solvent extraction theory indicates that pHinitiates the basis of an oxime’s metal complex for-

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mation and therefore its selectivity toward certainmetal species. The recommended optimum pH forsome of the commercial copper reagents is in a rangethat should maximise copper loading of the oxime.However, this pH range also tends to maximise iron(III)loading under certain operational conditions result-ing in low selectivity values. Recent operational pa-rameters at Girilambone Copper Company have high-lighted some of these conditions that have a majorinfluence on the oxime’s selectivity for copper overiron(Ill) in the leach solutions. The result is that the pHfor maximum copper extraction is no longer withinthe optimum range to maximise oxime selectivity.Therefore, specific copper and iron(III) pH isothermshave been determined on-site for the changing leachsolutions that are fed to the solvent extraction plantin order to optimise oxime selectivity. The influencesof solvent extraction plant configurations are alsodiscussed as a controlling parameter.

2:25 PMA Study of Copper/Iron Separation in Modern SolventExtraction Plants: D. C. Cupertino1; M. H. Charlton1;D. Buttar1; R. M. Swart1; C. J. Maes2; 1Zeneca Special-ties, Specialties Rsch. Ctr., P.O. Box 42, Hexagon House,Blackley, Manchester M9 8ZS England; 2Zeneca Spe-cialties, Acorga Metal Extraction Products, 3259 E.Harbour Dr., Suite 100, Phoenix, AZ 85034 USA Oxime based solvent extraction provides the userwith a selective concentration process for copper priorto electrowinning. The selectivity required is largelyfor copper(II) over iron(III) and this is achieved by thepreferential formation of the square planar copper-oxime complex in the organic phase. The copper/iron selectivity of oximes can however, be altered bymodifiers or other types of oximes and may be en-hanced in the presence of certain esters. Whilst theoxime based SX processes is important for operationsleaching copper from laterite ores, the high selectiv-ity will also be significant in processing streams aris-ing from other leaching regimes which are currentlyunder development, for example leaching of sulfidemineral ores. This paper presents some initial resultsusing Molecular Modeling techniques to further ourunderstanding of the nature of the copper/iron-oximecomplexation processes together with some plantstudies undertaken at a number of different mine sitesinvestigating selectivity, and other properties, for somemodified reagents. Some studies of the interfacialproperties of the these systems are reported to explainin part the practical observations.

2:50 PMInvestigation of Evaporative Losses in Solvent Extrac-tion Circuits: M. D. Bishop1; L. A. Gray1; M. G. Greene2;K. Bauer2; T. L. Young2; J. May3; K. E. Evans4; I l laAmerson-Treat5; 1Phillips Mining Chemicals, 1768 High-way 123, Bartlesville, OK 74004 USA; 2Versitech, Inc.,1438 W. San Lucas Dr., Tucson, AZ 85704 USA; 3BHPCopper Company, 200 Reddington Rd., San Manuel,AZ 85631 USA; 4EnviroNet, Inc., 7776 S. Pointe Parkw-ay, W., Suite 160, Phoenix, AZ 85044 USA; 5Oregon Gra-duate Institute, Dept. of Environ. Sci. and Eng., P.O.Box 91000, Portland, OR 97291-1000 USA Loss of organic solvent extraction circuits occursthrough several accepted methods. Losses are com-monly attributed to entrainment of the plant organicand evaporative loss of diluent. Evaporative losses of

diluent have been estimated using various models orby considering all losses over and above entrainmentto be due to evaporation. Other possible loss mecha-nisms are discussed and data on losses during weatherconditions are presented. Accurate estimation ofevaporative loss is vitally important to the industry dueto both cost factors and environmental concerns.Data for and description of the Diffusive Flux Modelare presented as an improved method of estimatingevaporative losses.

3:15 PMCrud Formation: Field Studies and Fundamental Stud-ies: Michael J. Virnig1; Stephen M. Olafson1; Gary A.Kordosky1; George A. Wolfe1; 1Henkel Corporation,2430 N. Huachuca Dr., Tuscon, AZ 85475 USA The formation of crud is a normal part of operat-ing a solvent extraction circuit for the recovery ofcopper. It periodically must be removed from the cir-cuit. This results in significant costs in terms of man-power, downtime, and loss of circuit organic. Fieldstudies have been carried out that show that the pres-ence of a thermodynamic modifier in the organicphase contributes to crud formation. In an effort tobetter understand what factors contribute to crudformation, laboratory studies involving competitiveadsorption studies with model solids have been car-ried out. The results of these laboratory studies will beintegrated with the results of the field studies to presenta better understanding of crud formation

3:40 PM Break

4:10 PMSolvent Extraction - How to Get Over Hard Times: PerttiPekkala1; Raimo Kuusisto1; Juhani Lyyra2; Bror Nyman1;Esa Lindell3; Eero Ekman3; 1Outokumpu EngineeringContractors Oy, P.O. Box 862, Espoo FIN-02201 Finland;2Outokumpu Research Oy, P.O. Box 60, Pori FIN-28101Finland; 3Outokumpu Engineering Services Oy, P.O.Box 863, Espoo FIN-02201 Finland Outokumpu has 25 years of experience in the SXarea. The development of the solvent extraction plantsresponds to an ever increasing demand for loweroperational costs and for adaptability to process dis-turbances with minimized risks. In this paper the fea-tures of the VSF (“Vertical Smooth Flow”) SX technol-ogy are described, such as the separated pumpingand mixing, the homogenous gentle mixing, the drop-let coalescence and the ultra pure settling. A majoradvantage of the mixing technology is the high stageefficiency of above 99 per cent. The connection be-tween this and some features of the settler front sec-tion is clarified. The present design of VSF plants isbased on experience of existing operations at, forexample, Zaldivar, Radomiro, Morenci, Kokkola andHarjavalta. These production plants cover a unit ca-pacity range of 60 to 3,600 m3/h expressed as a totalflow. It is evident that there are no restrictive factorsto increase the total flow up to 5,000-6,000 m 3/h byintroducing the VSF technology. The copper SX tech-nology has a long history reflecting many individualfeatures of the separate copper SX plants. Still it isnecessary to verify all actual running parameters bypilot tests taking into account impurities, chemicalsused etc. The design of SX plants is not only aboutthe delivery of equipment but also a process con-cept, and it is best tailor-made and adapted to spe-cific local requirements.

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4:35 PMPulsed Column Application in Copper Solvent Extrac-tion: M. Curtis Nielson1; Mark F. Vancas1; 1BatemanEngineering, Inc., 1860 E. River Rd., Suite 300, Tuscon,AZ 85718 USA The paper describes the design and operation ofpulsed columns as replacements for conventionalmixer/settlers. The advantages, which the columnsoffer, include a reduction in real estate for the plant,elimination of diluent evaporation, containment ofnoxious vapors and reduced crud formation. In ad-dition to the description of operation, the paper pre-sents the findings of laboratory tests of pulsed col-umns extracting copper from pregnant leach solu-tions and also delineates potential advantages of thepulsed column in copper solvent extraction.

5:00 PMRecent Advances in the Application of MolecularRecognition Technology (MRT) in the Copper Indus-try: John B. Dale1; Neil E. Izatt1; Ronald L. Bruening1;A. I. Reghezza2; J. Ch. Vergara2; J. A. V. Matta2; 1IBCAdvanced Technologies, Inc., P.O. Box 98, 856 E UtahValley Dr., American Fork, UT 84003 USA; 2Codelco,Chuquicamata Div., Chuquicamata, Chile A primary objective of copper mining, smelting andrefining operations is the cost-effective, efficient, andenvironmentally-acceptable control of the level ofvarious metal ions throughout the processing andeffluent treatment flowsheets. Effective ionic controlmaximizes product and by-product quality, allows forbroad flexibility in sourcing impurity laden ores, mini-mizes capital and operating costs, and can achievezero discharge operations. In order to meet increas-ingly stringent cost, environmental and product qual-ity requirements, separation technologies are neededthat can selectively remove and recover deleteriousor valuable ions. Ideally, the subsequently obtainedsalts or metals can be recycled in the process, dis-posed of in an environmentally acceptable manner,or sold as valuable by-products. The use of MRT, ahighly selective separations technology, has beendemonstrated to be a cost effective, efficient, andenvironmentally-sound treatment for a wide range ofcations and anions that are commonly found in cop-per electrorefining and electrowinning circuits, as wellas in environmental treatment operations. These in-clude heavy and transition metals, precious metals,halides and alkali/alkaline earths. This paper will re-view a number of areas of interest including: recov-ery and refining of platinum group metals from cop-per anode slimes, recovery of copper from acid minedrainage streams, extraction of Bi, Sb and Cl fromcopper electrorefining and electrowinning circuits.

5:25 PMDirect Cementation and Dissolution of Copper in Di-(2-Ethylhexyl) Phosphoric Acid : C. Flores1; T. J.O’Keefe2; 1BHP Copper, P.O. Box M, San Manuel, AZ85631 USA; 2University of Missouri-Rolla, Metallu. Eng.Dept., Matls. Rsch. Ctr., Rolla, MO 65401 USA The direct cementation of copper from a loadedD2EBPA 20% vol. in kerosene using zinc, zinc-lead al-loy and iron metallic powders was studied. Copperwas loaded into the organic solvent from an aque-ous copper sulfate solution. Results indicated thatcopper is reduced spontaneously with relatively fastreaction rates. The effects of several operating pa-

rameters such as water content in the organic sys-tem, initial copper concentration, reductant surfacearea, oxygen and nitrogen atmosphere, intensity ofthe agitation and temperature on the galvanic strip-ping of copper were studied. For a better understand-ing of the electrochemical reactions involved in thegalvanic stripping, the dissolution of metallic copperin the organic solvent was also studied. Copper didnot dissolve unless a small amount of water waspresent in the organic system. The results and pos-sible reaction mechanisms are discussed.

Pyrometallurgy-Operations: Session IV

Tuesday PM Room: EstrellaOctober 12, 1999 Location: Pointe Hilton Resort

Session Chair: Pete Chen, Phelps Dodge MiningCompany, Phoenix, AZ 85004-3014 USA; F. Puchi,Efepe, Ingenieros, Santiago, Chile

2:00 PMImproving Smelter Performance through Developmentof People: R. K. Hill1; A. G. Ross1; 1Phelps DodgeHidalgo, Inc., P.O. Box 67, Playas, NM 88009 USA The Hidalgo Smelter successfully reduced operat-ing costs by 25% compared to the previous two yearsthrough a focused holistic approach to developmentof its entire workforce. The first phase involved basicteam training skills for natural work teams. The sec-ond phase provided leadership training via break-through education to 40 of the smelter leaders-bothhourly and salaried. The third phase stretched out theteams training to include rewards for performancethat resulted in hourly teams converting to salariedstatus-part of a company wide initiative. The fourthphase saw 1998 become the “Year of Safe Cost Re-duction” where 7 breakthrough projects focused ondifferent areas of expenditure. Implementation of leanmanufacturing as a tool for teams to truly get theirarms around what they controlled, introduced ac-countability and responsibility for operating results atthe team level. This will allow the release of experi-enced supervisors from this role, to a pool of techni-cal expertise, where our future breakthroughs will bedesigned and implemented.

2:25 PMThe Copper Smelters of the 2010 - A Vision of the Fu-ture: Sergio Demetrio1; Nelson Santander2; MarcoSolar3; 1ConOpti S.A., Cerro San Ramon 1491, LasCondes, Santiago, Chile; 2U. de Chile and U. Mayor,Dept. of Metallu. Eng., Santiago, Chile; 3MasbingIngenieria, Santiago, Chile Based on the current reality of the copper smeltersindustry, besides the advances that have been andare expected for the next few years, the authorspresent a futurist vision of the processing of copperconcentrates and copper smelters in the years 2000.Outlined new development strategies and ways ofimprovement in this business, including research, de-velopment and management of the works that to-day posses characteristics of a profitable operation,as well as the changes expected with respect to the

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entry of new actors and the creation of new prod-ucts. The authors finally bet for small or tailor-madesmelters with ad hoc technology for their raw materi-als and few units to coordinate devoted to specificconcentrates using high technology and low man-power. Considering the in-situ hydrometallurgicalroute, as well as the pyrometallurgical route in worksor conversion facilities that buy or process white metaland produce copper and other metals associatedwith this such as gold and silver, besides sulfuric acid,plants which should be strategically located in zoneswith high sulfuric acid price to make this a productwhich contributes to the profitability of the business.

2:50 PMBath Smelting in the Noranda Process Reactor andthe El Teniente Converter Compared: Cameron Har-ris1; 1Kvaerner Metals, 12657 Alcosta Blvd., San Ramon,CA 94583 USA Noranda’s Process Reactor and Codelco’s TenienteConverter are physically similar vessels, which leadsto the commonly held misconception that the twoprocesses are the same. However, notable differencesin chemistry, operating philosophy, and constructionmake them quite dissimilar. This paper compares andcontrasts the Noranda Reactor and the Teniente Con-verter, and attempts to explain some of the apparentdifferences in behavior and performance. The resultsof a worldwide survey of most operating NorandaReactors and Teniente Converters, along with thoseprocesses that have ceased operation or are plan-ning to be started-up in the future, are presented.

3:15 PM1999 Rebuild of the BHP San Manuel Outokumpu FlashFurnace: David M. Jones1; Ray Cardoza1; AnthonyBaus1; 1BHP Copper North America, P.O. Box M, SanManuel, AZ 85631 USA In May 1999 the first campaign of the BHP SanManuel flash smelting furnace (FSF) will be concludedafter having set world records for both campaignlength and tonnage smelted for an Outokumpu cop-per flash smelting furnace. This paper reviews plannedprocess and equipment modifications including: theinstallation of a new 36,000 mt concentrate storagefacility; replacement of the existing dryer electrostaticprecipitator with a baghouse; modification of the FSFdry charge bin and feed system to achieve mass flowand uniform feed to the concentrate burner; modifi-cations to the FSF and its ancillary cooling systems;modifications to the waste heat boiler and offgas han-dling system to increase gas handling capacity andimprove process efficiency; and improvements to theFSF fugitive gas collection system. A brief review ofthe planning and execution of the scheduled 45 dayshutdown is also given.

3:40 PM Break

4:10 PMOptimization of the Blast Furnace Process in a Sec-ondary Copper Smelter: Andreas Nolte1; RalfKreymann1; 1Huttenwerke Kayser AG, Postfach 15 60,Lunen D-44505 Germany In 1999, Huttenwerke Kayser AG (HK) plant in Ger-many will produce more than 180,000 t/y of electro-lytic refined copper. To achieve this production frommaterials with copper grades from two to seventypercent and diverse copper alloys, HK operates three

blast furnaces, one holding furnace, two Peirce Smithconverters and two anode furnaces. Technical, met-allurgical and economic factors for the ongoing pro-cess optimization are outlined. The fluctuating qual-ity and quantity of raw materials renders complex thisoptimization. The principal variables are the qualityand quantity of process consumables: coke, copper-iron, limestone, oxygen, as well as the blending offeedstock and a new organization of the operatingcrews. The search for new metallurgical process pa-rameters is ongoing. HK started with an intensive re-search program in November 1997. As a result it willbe possible to cut processing costs by about ten per-cent, to increase the blast furnace capacity by tenpercent and to lower the metallurgical losses of cop-per and tin in the slag by more than ten percent. Thepresentation concludes with information of futuresteps to continue the optimization process.

4:35 PMDistribution and Removal of Impurities in CopperSmelting in Guixi Smelter: Yuan Zeping1; 1JiangxiCopper Company, Yejin Ave., Guixi, Jiangxi 335424ROC The distributions of impurities in the copper melt,the slag and the gas phase in copper flash smeltingprocess were under study in the Guixi smelter, par-ticularly during operating conditions of high oxygenenrichment with production of high grade matte.Several methods for the removal of impurities such asAs, Sb and Bi in the copper smelting process weredeveloped and implemented at the Guixi smelter. Thispaper described the effects of high oxygen enrich-ment, elevated matte grade, high temperature andhigh production rate on the distribution of impurities,methods adopted at the smelter for the removal ofimpurities, and the associated benefits in the utiliza-tion of these removal techniques which include themathematical model for material blending, high ther-mal intensity operation at the flash furnace, extendedconverter blowing, and injection of slag modifiersconsisting of Na2C03 and CaO powder mixture to theconverters and anode furnaces.

5:00 PMThe Design of the Ausmelt Technology Smelter atZhong Tiao Shan’s Houma Smelter, People’s Republicof China: E. N. Mounsey1; H. Li1; J. W. Floyd1; 1AusmeltLimited, A.C.N. 005 884 355, 12 Kitchen Rd.,Dandenong, Victoria 3175 Australia The paper addresses the design of the Zhong TiaoShan Company (ZTS) Houma Ausmelt Technologycopper smelter in People’s Republic of China. Thesmelter represents the third copper smelter develop-ment using Ausmelt Technology, the first large scale(35,000 tpy blister copper) and the first smelter to usethe Ausmelt Technology smelting and converting pro-cess steps in separate TSL vessels in a continuouslyoperated process. The project will be realised throughthe combined efforts of ZTS, Ausmelt and ENFI, theBeijing Non-Ferrous Engineering Institute who providedpartial detail engineering services in China. Ausmeltwill provide the technology licence, basic and de-tailed furnace engineering packages and additionaltechnical services including cold commissioning sup-port and hot commissioning supervision.

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Pyrometallurgy-Operations: Session V

Tuesday PM Room: FlagstaffOctober 12, 1999 Location: Pointe Hilton Resort

Session Chair: Tony Weddick, Kennecott UtahCopper Corporation, Magna, UT 84044-6001 USA;A. Luraschi, CADE-IDEPE, Santiago, Chile

2:00 PMFurnace Cooling Design for Modern, High-Intensity Py-rometallurgical Processes: N. Voermann1; F. Ham1; J.Merry1; R. Veenstra1; K. Hutchinson1; 1Hatch Associ-ates, 2800 Speakman Dr., Mississauga, Ontario,Canada L5K 2R7 The increasing need for robust pryrometallurgicalfurnace construction is driven by two trends in thecopper and other base metals smelting industry: thedesign for increased production within a single fur-nace line by greatly increasing smelting intensities,which generates high heat fluxes to the crucible walls,and the operational and economic imperatives ofmaintaining high percentage on-line times and longcampaign lives between rebuilds. A key feature offurnaces capable of producing at high rates, whilecontaining intense processes, is a strong, thermallyrobust wall cooling system. Equally important designaspects include the furnace steel structure, refracto-ries, a cooling water supply and piping arrangementfor safety from leaks and disruptions, and instrumen-tation/controls for monitoring and rapid mitigationof process excursions. Integration of the cooling ele-ments into these furnace systems is essential for opti-mum performance of the cooling elements, and in-deed the entire furnace. This paper discusses the de-velopment of a composite copper/refractory water-cooled design, which has been successfully imple-mented on several copper smelting and convertingfurnaces, including Kennecott’s flash converting fur-nace, INCO’s MK reactor, and Kidd Creek’s convert-ing furnace.

2:25 PMTeniente Converter Slag Cleaning in an Electric Fur-nace at the Las Ventanas Smelter: Ricardo Ponce1;Gerardo Sánchez1; 1Empres Nacional de Minería(ENAMI), Las Ventanas Smelter & Refinery, Casilla 126-B, Quintero, Chile In recent years, ENAMI implemented modernisationplans at its two smelters in order to meet thegovernment’s environmental regulations introducedin the early 1990's. The modernisation plans definedthe new SO2 and particulates emission targets, dead-lines for compliance, and the revised treatment ca-pacities of the smelters. At Las Ventanas smelter, theprincipal process change consisted of eliminating thereverberatory furnace. All the smelter feed is currentlyprocessed in a 4m diameter, 14m long Teniente Con-verter, using up to 34% oxygen enriched air. Dry con-centrate is injected into the bath through tuyeres. Afuel oil burner compensates for any process heatdeficiency. The Teniente Converter high copper con-tent slag is cleaned in an electric furnace. This fur-nace is also used to melt internal reverts. This paper

will discuss the successful operation of the slag clean-ing electric furnace.

2:50 PMUtilization of Excess Reaction Heat in the MitsubishiConverting Furnace: Osamu “Sam” Iida1; TetsuroSakai1; Hiroshi Kumada1; 1Mitsubishi Materials Corpo-ration, Naoshima Smelter & Refinery, 4049-1 Naoshima-Cho, Kagawa-Gun, Kagawa 761-3110 Japan In the Mitsubishi converting furnace (C-furnace),molten matte continuously undergoes intensive con-version into blister, and an excess amount of heat isgenerated, even after taking into account heat lossfrom the furnace, off-gas, and latent heat of melt. Toabsorb excess heat in C-furnace, recycled granulatedconverting slags (C-slag) were wastefully charged inthe C-furnace. In contrast, supplementary coal is nec-essary to make up a shortage of reaction heat inSmelting furnace (S-furnace). To utilize the excess heatof the C-furnace effectively and accommodate theunbalance of heat utilization between S and C fur-naces, three technological innovations have beencarried out. Spent anode charging facilities in C-fur-nace was modified, in order to solve some spent an-odes hitting and eroding the hearth bricks. Cubicpressed copper scrap charging facilities were installedin C-furnace. Facilities were newly installed in C-fur-nace to treat neutralized residue from the wastewa-ter and dust treatment plants, previously treated inthe smelting furnace. Above innovations led to thefurther effective utilization of heat, increase in pro-duction, and savings in energy costs.

3:15 PMImprovements to BHP Hartley Platinum’s Smelting Fur-nace: J. Sarvinis1; S. de Vries1; K. Joiner1; C. vanMierlo1; N. Voermann1; F. Stober2; C. Rule2; P. Majoko2;1Hatch Associates Limited, 2800 Speakman Dr.,Mississauga, Ontario, Canada L5K 2R7 ; 2BHP HartleyPlatinum, P.O. Box CY 2288, Causeway, Harare, Zim-babwe BHP Hartley Platinum operates an electric smeltingfurnace to treat Cu-Ni-PGM concentrate at its plantin Selous, Zimbabwe. The furnace, originally built byothers, has experienced problems including severerefractory erosion of the sidewall. Hatch Associateshas designed several important improvements to thefurnace, including: water-cooled copper cooling el-ements in the slag zone; air-cooled copper coolingfins at the metal level; water-cooled copper tapholes;binding system providing vertical refractory compres-sion; electrode seals; new feed pipes. Novel construc-tion techniques employed on this project to reduceshutdown duration are discussed.

3:40 PM Break

4:10 PMElectric Settling Furnace Operations at the CyprusMiami Mining Corporation Copper Smelter: Jason EricSallee1; Vladimir Ushakov1; 1Cyprus Miami MiningCorporation, Dept. of Pyrometall., P.O. Box 4444,Claypool, AZ 85532 USA Ongoing operations at the Cyprus Miami Smelterinvolve the use of an electric furnace for final settlingof copper matte from discard slag. Proper operationof the electric settling furnace is a major factor in mini-mizing losses of copper to the discard slag. Recenttest work at the smelter has shown improvement in

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the operation of the electric furnace with a subse-quent improvement with regard to the copper losses.This paper presents a general discussion of the CyprusMiami Smelter operation, past results with respect tocopper losses, recent operational changes and testwork, and the subsequent results.

4:35 PMControl of Tapping and Launder Emissions: J. H. deVisser1; J. A. Davis1; M. M. Weaver2; 1DESOM Environ-mental Systems Limited, 1211 Gorham St., Unit 1,Newmarket, Ontario, Canada L3Y 7V1 ; 2KennecottUtah Copper Corporation, Smelter Eng. Grp., 12000W. 2100 S., Magna, UT 84044-6001 USA The transfer of molten metal in smelting or refiningoperations is typically performed in open trough-typelaunders that are constructed of either water-cooledcopper troughs or refractory lined steel jackets. Thistransfer can be either continuous or batch. Batchoperations transfer metal through an open launder.The uncovered launder has many operational andenvironmental drawbacks. In order to improve work-place hygiene, designs have evolved toward venti-lated launder covers that are connected to second-ary exhaust systems that use negative pressure underthe cover removing fume and hot gases to second-ary fume control devices. In smelting operations, avariety of covers have been employed which insu-late the launder and contain the fumes and also pro-vide additional heat along the length of the launderthrough a series of premix or inspiration-type burnersthat add combustion products to the normal fumeload in the launder. Cover designs have proven tobe inadequate in that hinged unventilated covershinder convenient access while heated ventilatedcovers are costly to maintain. Covers that employrefractory bricks and overhead enclosure-type ex-haust hoods have been somewhat successful, but re-strict operator movement and require large volumesof exhaust air. An example is given of a cover andoff-gas system for launders that is designed to pro-vide superior insulation and heating capabilities, aswell as better control of the fume gases and ease ofmaintenance. The cover system must maintain thebalance between maintaining launder heat andfume removal. The construction of the covers mustbe able to withstand high internal temperatures andmaintain its structural properties.

5:00 PMApplication of Advanced Process Control Principlesto Copper Smelting: A. A. Shook1; S. Crisafulli2; R. A.Cockerell2; 1BHP Copper, Inc., P.O. Box M, SanManuel, Arizona 85631 USA; 2CICS Automation PtyLimited, P.O. Box 570, Wallsend, NSW 2287 Australia The modern approach to process control seeksmaximization of plant efficiency through the prag-matic integration of standard, enhanced and ad-vanced control strategies. This paper describes theapplication of advanced process control principlesto copper smelting processes based upon the experi-ence of the authors. The successful implementationof any form of process control relies upon a combi-nation of many key factors such as instrumentationand a knowledge of the process dynamics. In appli-cations of advanced process control, where the end-user may be either seeking to improve the perfor-mance of an existing controlled process or installing

a control system for a difficult process, these factorsbecome even more significant. The authors’ experi-ence has been that the most successful projects forprocess control have occurred where there is a de-tailed understanding of the process to be controlled.This understanding is usually already held on-site, butoften the dynamic elements need to be determinedby additional studies and testing. This paper will pro-vide a discussion on these and other issues requiredfor applying modern control techniques. A case studyat the BHP Copper San Manuel smelter will be incor-porated to support the above discussions.

5:25 PMRecent Operation of the Flash Smelting Furnace atSaganoseki Smelter: Yushiro Hirai1; Yutaka Yasuda2;Mitsumasa Hoshi2; 1Nippon Mining and Metals Com-pany Limited, Tech. Dev. Ctr., Miyata, Hitachi City,Ibaraki 317-0055 Japan; 2Saganoseki Smelter and Re-finery, Nippon Mining & Metals Co. Ltd., Saganoseki,Oita 879-2201 Japan Saganoseki smelter and refinery had operated twoflash smelting furnaces from 1973, attaining 330,000mtpy of copper production in 1989. In 1996, however,it carried out a “integration of two flash furnaces”.That is, it doubled the feeding capacity to one flashfurnace to shut down another furnace while main-taining the same production. Single flash furnace op-eration has successfully started in March 1996 accom-plishing a great reduction of the total production cost.The production was reached to 350,000 mtpy in 1997,and further increased to 450,000 mtpy by executingthe expansion program with single flash furnace in1998. This paper introduces results of the single flashfurnace operation and describes about an outline ofthe expansion.

Smelting: Technology Development,Process Modeling and Fundamentals:Process Modeling and Control II/Funda-mental Studies

Tuesday PM Room: GoldwaterOctober 12, 1999 Location: Pointe Hilton Resort

Session Chairs: Frank Jorgensen, CSIRO Minerals,G.K. Williams Cooperative Rsch. Ctr. for ExtractiveMetallurgy, Clayton South Victoria 3169 Australia;Carlos Landolt, Inco Limited, Ontario Division,Sudbury, Ontario, Canada

2:00 PMDynamic Simulation of the Flash Furnace in theChagres Smelter: Roberto Parada1; Rene Busta-mante2; 1Chagres Smelter, Compañia Minera Dispu-tada de las Condes S.A., Avda. Pedro de Valdivia291, Santiago, Chile; 2Universidad de Santiago deChile, Departamento de Ingenieria Metalúrgica,Casilla10233, Santiago, Chile A real-time dynamic simulation model has beendeveloped to characterise the flash furnace opera-tion at the Chagres smelter. This model permits theoperators to plan the process to meet the Peirce Smith

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converters schedules and feed the acid plant withgases that satisfy its best operating efficiency range.Essential control parameters for the furnace (processair enrichment, oxygen coefficient and supplemen-tary heat) are calculated to satisfy process targetssuch as matte grade, slag silica and matte/slag tem-peratures. These calculations are carried out with areal-time simulation. Flash furnace control and op-erational stability permits setting up control strategiesthat streamline the flow of copper to converters andof sulphur to the acid plant.

2:25 PMNumerical and Experimental Modeling of the Con-centrate Burner in a Flash Smelting Furnace: F.Guevara1; R. Fuentes1; A. Valencia2; 1Codelco-Chile,Instit. for Innov. in Mining and Metallu., Avenida delParque 4980, Ciudad Empresarial, Huechuraba,Santiago, Chile; 2Universidad de Chile, Mech. Eng.Dept., Casilla 2777, Santiago, Chile The paper presents results of physical and turbu-lent three-dimensional numerical simulation of the gasflow in the wind box and reaction shaft of the con-centrate burner of a flash furnace. Physical simula-tion work was carried out in a 1:5 linear scale model,where the velocity field was measured using a Pitottube. The mathematical model consists of the three-dimensional averaged Navier-Stokes equations, tur-bulent kinetic energy and dissipation of turbulent ki-netic energy using the Renormalization Group (RNG)theory for the k-ε turbulence model. Computationswere performed using FLUENT, based in a finite-vol-ume code. The geometry of the concentrate burnerwas separated in two sections: wind box and reac-tion tower. Results obtained at the exit of the windbox were used as boundary conditions for the reac-tion shaft. The effect of boundary conditions on thenumerical results was also studied. Results of physicaland numerical simulations show an asymmetry of thevelocity field at the exit of wind box. This asymmetry ispossibly due to existence of a separated flow in theback of the exit ring. The agreement of physical andnumerical results assess the capacity of the turbulenceRNG k-ε model to reproduce correctly the behaviourof the velocity field at the exit of the concentrateburner.

2:50 PMApplication of a Reacting CFD Model to Drop TubeKinetics and Flash Smelter Combustion: B. R. Adams1;K. A. Davis1; M. P. Heap1; A. F. Sarofim1; G. A. Eltring-ham2; A. A. Shook3; 1Reaction Engineering Interna-tional, 77 West, 200 S., Suite 210, Salt Lake City, UT84101 USA; 2BHP Copper, 550 California St., San Fran-cisco, CA 94104-1020 USA; 3BHP Copper, 7400 N.Oracle Rd., Suite 200, Tucson, AZ 85704 USA This paper discusses the use of a reacting CFDmodel to determine chalcopyrite kinetics in a droptube furnace and to predict the reaction of a chal-copyrite concentrate in the reaction shaft of an in-dustrial smelter. Reacting CFD codes can be appliedto determine the consequences of the interaction ofgas with particles and therefore improve the abilityto derive kinetic parameters that take into accountthe temperature and oxidation histories that differentparticles will see. This paper describes the applica-tion of such a model to derive improved kinetic pa-rameters for the pyrolysis and oxidation of chalcopy-

rite. The reaction shaft model includes the effects ofturbulent fluid mechanics, entrained flow mixing, tur-bulent particle dispersion, heterogeneous particlereactions, radiative and convective heat transfer, andsurface and bath deposition rates. Particle reactionand composition characteristics are predicted as afunction of particle trajectory and deposition and areused to aid in evaluating shaft performance.

3:15 PMNumerical Modeling of Heat Transfer of a Smelter Ladle,With and Without a Refractory Lining: P. Ruz1; M.Rosales1; R. Fuentes1; J. Averous2; 1Codelco-Chile,Instit. for Innov. in Mining and Metallu., Avenida delParque 4980, Ciudad Empresarial, Huechuaraba,Santiago, Chile; 2Ecole des Mines de Paris, Corps Tech-niques de I’Etat, 60 Blvd. St. Michel 75272, Paris, Cedex06 France A melt transfer ladle was 3D modeled by means ofa mathematical fluid dynamics and heat transfer pro-gram. Internal temperature profiles were calculatedas a time function for a normal ladle and for a pre-heated refractory lined ladle. It was shown that in anormal ladle the molten metal cools down quicklyforming accretions. By using an inner lining there arepractically no accretions build up within a typical timeof operation. Therefore, by applying a refractory lin-ing to a melt transfer ladle and keeping it at a mod-erate to high temperature it is possible to reduce colddope circulation in the smelter.

3:40 PM Break

4:10 PMSlag Chemistry of the New Noranda Continuous Con-verter: Manuel Zamalloa1; Eva Carissimi2; 1Noranda,Inc., Technology Center, 240 Hymus Blvd., Pointe-Claire, Québec, Canada H9R 1G5 The outstanding metallurgical performance of theNoranda continuous converter (NCv) in operationsince November 1997 has allowed the company tomeet production and environmental targets. Thisachievement positions this new technology as a strongalternative continuous converting technology for cop-per production. Knowledge of slag chemistry has beenimportant in this respect. The purpose of this paper isto discuss the effect of key parameters including tem-perature, oxygen potential, slag composition andlevels of copper oxide in slag on the conditions lead-ing to magnetite precipitation, as well as on the con-ditions affecting the liquidus ranges of NCv slag. Theabove variables are evaluated using industrial dataand thermodynamic predictions. Practical implica-tions of customizing operational fluxing proceduresto determine optimum operating windows are alsodiscussed.

4:35 PMModeling of Slag-Skimming in a Peirce-Smith Con-verter: Jong-Leng Liow1; George E. Assaad1; PetarLiovic1; Neil Boon Gray1; Murray Rudman2; 1The Uni-versity of Melbourne, Dept. of Chem. Eng., GKW CRCfor Extractive Metallu., Parkville, Victoria 3052 Austra-lia; 2CSIRO, Div. of Bldg., Constru. and Eng., P.O. Box56, Graham Rd., Highett, Victoria 3190 Australia The entrainment of copper matte in the slag dur-ing the slag skimming stage of a Peirce-Smith con-verter was studied with a dam break model. Experi-ments were carried out with a range of fluid pairs

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where the lighter fluid was allowed to overflow a weirand the amount of entrained heavier fluid measured.The resulting entrainment is measured as the ratio ofthe heavy to light fluid withdrawn. The fluid pairs in-clude oil-water, water-glycerol and salt solutions-wa-ter pairs to cover a wide range of densities and vis-cosities. It was found that the Richardson number, Ri,correlates the entrainment well. For the case of theliquid-liquid interface initially at the same height asthe weir, the entrainment was found to vary with Ri-1/

3. The transient flow was simulated with a volume offluid (VOF) code written in-house and used a stairstepapproach to represent flow obstacles. The code wasvalidated against the experimental results with goodagreement for the variation of the heights of the twofluid with time. The simulation showed that the pre-vailing mechanism for entrainment is due to a pres-sure differential created across the liquid in the con-verter during pouring resulting in the heavier liquidbeing rotated upwards and over the weir.

5:00 PMSome Aspects on Matte Settling in Copper Smelting:Kim Olof Fagerlund1; Heikki Jalkanen1; 1Helsinki Uni-versity of Technology, Dept. of Matls. Sci. and RockEng., Lab. of Metallu., Espoo FIN-02150 Finland Theoretically and experimentally determined cop-per matte settling rate in iron silicate slag has beendiscussed. Separation and settling rate measurementsof sand, homogenised slag and 25%Cu concentrate,63%Cu industrial, and 71%Cu synthetic copper matteswere carried out by mixing crushed slag and mattesamples with silica sand in an alumina crucible andmelting at 1300-1350ϒC. Two different types of slagcompositions were employed, with Fe/SiO2-ratio 1.4and 1.7. The separation rate was followed by takingsamples from the melt. As expected, the settling rateof copper matte in fayalite slag depended on theslag composition, where the increasing silica de-creased the matte settling rate. Microanalysis of so-lidified slags showed that the rate of separation oflow grade matte was low compared with high gradematte and the presence of a very small size fractionof matte droplets in slag remained unsettled in stag-nant fluid. The production of sulfur dioxide gas insidethe molten bath was found to be possible up to acertain iron sulfide content in the matte. Also, cop-per matte settling rates in industrial furnaces havebeen discussed.

5:25 PMEffervescence During Desulfurization of Copper Melts:Ralph Harris1; I. Roumeliotis1; 1McGill University, Dept.of Mining and Metall. Eng., Rm. 2220 Wong Bldg., 3610University St., Montreal, Québec, Canada H3A 2B2 Blister copper melts of 800 g to 1000 g containingless than I wt % S and up to 3 wt % Ni were desulfur-ized at 1523 K in air or by a pure oxygen jet blown at75, 500 and 1000 cm3/min, from I cm above the melt.Rates of desulfurization and oxygen pickup weremeasured and visible surface phenomena were pho-tographed and videotaped. It was observed that S02was evolved from Cu-S melts in a manner reminiscentof the effervescence seen in carbonated drinks. Theeffervescence lasted up to 20 minutes and resulted inthe ejection of material up to a height 50 cm abovethe melt surface. Sporadic discharge of large bubbleswas also observed in a Ni containing melt top-blown

with oxygen at 1000 cm3/min. The Cu-S melts top-blown with oxygen experienced faster sulfur elimina-tion as compared to stagnant melts exposed to airand experienced only a single period of turbulent So2evolution which occurred almost immediately afteroxygen injection commenced. The Cu-S melts ex-posed to air experienced multiple episodes of effer-vescence. The stagnant blister copper melt contain-ing nickel did not exhibit effervescent behaviour andexperienced a lower rate of sulfur elimination com-pared to Cu-S melts tested under similar conditions.The present article examines the role of surface phe-nomena in determining the observed behaviour.

Plenary Lectures: Session III

Wednesday AM Room: Flagstaff/Goldwater/ Indigo/Jerome

October 13, 1999 Location: Pointe Hilton Resort

Session Chairs: David Geoge, Kennecott UtahCopper, Salt Lake City, UT USA; F. Puchi, Chile

8:30 AMCopper Extraction from the 60’s into the 21st Century:W. G. Davenport1; 1University of Arizona, Dept. Matls.Sci. and Eng., #12, Tuscon, AZ 85721 USA Changes in copper extraction from 1960 till todayare documented. The top ten changes have been:replacement of reverberatory smelting by high inten-sity oxygen rich smelting, growth of the Outokumpuflash smelting to over 50% of the world’s smelting ca-pacity, successful development of single furnacecoppermaking but only for low slag fall concentrates,replacement of the batch Peirce-Smith converter bycontinuous converting, but only in a few cases, in-creased SO2 capture throughout the industry, mainlyas sulfuric acid, development of low initiation tem-perature “big bight” Cs catalysts for treating the con-tinuous high SO2 strength gases from continuous smelt-ing/converting, complete replacement of reverbera-tory anode scrap and cathode melting furnaces bythe Asarco shaft furnace, adoption of stainless steelpermanent cathodes and automated stripping tech-nology for electrorefining and electrowinning, com-plete elimination of wire bar casting by continuousbar casting/rod rolling, and development and adop-tion of extractants for turning weak impure leach so-lutions into strong pure electrolytes. It is postulatedthat the biggest possible change over the next 20years would be complete replacement of smelting/converting by hydrometallurgical processing. How-ever, this seems unlikely due to copper purity, pre-cious metal recovery, and economic concerns. Theincreasing value of sulfuric acid to many copper com-panies give chalcopyrite smelting/oxide-supergeneleaching a nice synergy especially with the energycredits now coming from continuous smelters and theiracid plants.

9:15 AMAdvances in the Copper Industry - Future Develop-ment and Environmental Constraints: W. Marnette1;1Norddentsche Affinerie, Hovestrabe 50, Hamburg D-20539 Germany

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This plenary lecture discusses some of the issuesaffecting the pace of developments in the copperindustry. This includes developments affecting boththe production and uses of copper. Environmentalconstraints can influence the nature of developmentson both the production and consumption side andthe impact of these aspects is reviewed as well.

10:00 AM Break

Electrorefining: Anodes and Cathodes

Wednesday AM Room: IndigoOctober 13, 1999 Location: Pointe Hilton Resort

Session Chairs: P. L. Claessens, Noranda Technol-ogy Centre, Pointe Claire, Québec, Canada HH9R1G5; J. P. Evans, G. Engineering, Toronto, Ontario,Canada M9W 5X9

10:30 AMUpdate on the Contilanod® Process - Continuous Castand Sheared Anodes: P. Regan1; M. Schwarze2;1Hazelett Strip-Casting Corporation, P.O. Box 600,Colchester, VT 05446 USA; 2Mannesmann DemagMétallurgie, Ohlerkirchweg 66, Postfach 100645,Monchengladbach 41006 Germany Following the introduction of the Contilanod pro-cess over 10 years ago at Copper Range and IMIRefiners, significant changes and advances havebeen made to this pioneering anode productiontechnique. A new radial flow metal feeding concepthas been developed that allows a substantial increasein casting rates on the Hazelett® twin-belt caster. Tocut the 45 mm thick continuous anode plate intoshaped anodes at rates of 100 t/h or more, a fullymoving hydraulic shear designed by MannesmannDemag has replaced the slower speed plasma cut-ting torch. Details of the new caster and shear arepresented along with operating results from the newlines starting up in 1999 at the Gresik smelter/refineryin Indonesia and the completely revitalized Mans-felder Kupfer und Messing complex in Germany.

10:55 AMAluminum Diffusion Protection for Copper AnodeMoulds: J. Riccardi1; A. Park2; 1PGE Industrial, Inc.,3589 Old U.S. 23, Brighton, MI 84114 USA; 2GeneralMetal Diffusion, Inc., 815 Great Northern Rd., Sault Ste.Marie, Ontario, Canada D6A 5K7 Copper refineries use massive copper castings asmoulds into which impure molten copper from a ro-tary or reverberatory furnace is poured to form an-odes for subsequent electrolytic refining. To facilitateremoval of the copper anodes from the mould andto prolong the life of the mould itself, it is traditionalto spray the mould surface prior to each use with anaqueous slurry of barite, boneash, etc. This slurry ap-plication leads to poor housekeeping, operating costsare escalated by the cost of the slurry, and additionalproblems in the subsequent refining process are ex-perienced because of the carry-over of excess unde-sirable barite. A one-time application of a diffusedlayer of aluminum to the surface of the copper mouldprior to putting it into service has been found to pro-

vide extended mould life and to facilitate anode re-moval, as well as reducing reagent consumption,thereby reducing operating costs at both the anodemanufacturing and refining stages.

11:20 AMA Mineralogical Study of Nodulated Copper Cath-odes: J. E. Dutrizac1; T. T. Chen1; 1CANMET, 555 BoothSt., Ottawa, Canada K1A 0G1 Mineralogical studies were carried out on nodu-lated copper cathodes from three primary refineriesto characterize the nodular growths and to elucidatethe causes of the nodulation. Nodulation is often ini-tiated at the surface of the starter sheet or the stain-less steel plating blank, although a layer of smoothcopper sometimes is deposited before nodulationcommences. In some instances, the “roots” of thenodules exhibit a pronounced dendritic texture thatis associated with an abundance of cavities. Slimesparticles are not usually associated with these growthfeatures which lead to a globular surface deposit.The globules sometimes develop into larger nodules,and this type of nodulation is likely caused by im-proper addition agent concentrations. The noduleson most cathodes, however, exhibit “roots” at thecontact with the substrate that are associated withmicrocavities and large clusters (>40 µm) of slimes par-ticles. The slimes constituents are commonly Ag pow-der, PbSO4 and Cu 2(Se,Te) but not AgCu(Se,Te) orAg2(Se,Te). The size of the slimes clusters, rather thantheir composition, appears to be the important fac-tor causing the copper to grow into nodules. Tiny in-dividual slimes particles themselves do not appear tocause cathode nodulation.

11:45 AMPost-Passivation Reactions Occurring at the Anodeduring Copper Electrorefining: M. S. Moats1; J. B.Hiskey1; 1University of Arizona, Department of Materi-als Science and Engineering, P.O. Box 210012, Tuc-son, AZ 85721 USA A considerable amount of research has been con-ducted to determine the causes of anode passiva-tion. Chemical and electrochemical reactions thatoccur after passivation have received little attention.Chronopotentiometry, linear sweep voltammetry,cyclic voltammetry, and impedance spectroscopyhave been used to elucidate three reactions thatoccur after passivation of commercial copper an-odes. These involve the dissolution of silver and sub-sequent cementation and transformation of selenides,the oxidation of lead sulfate to lead oxide, and oxy-gen evolution. The amount of silver dissolution de-pends on the silver content of the anode, the time topassivation, and the molar ratio of Ag/(Se+Te). Theoxidation of lead from PbSO4 to PbOx explains apotential plateau of oxygen evolution. Silver affectsthe duration of oxygen evolution on the PbOx. An-odes containing kupferglimmer display a character-istic oxygen evolution potential. It is believed thatkupferglimmer provides a lower overpotential for oxy-gen evolution than the other slime phases or passi-vated surface.

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Environment, Health & Safety: Session I

Wednesday AM Room: CopperOctober 13, 1999 Location: Pointe Hilton Resort

Session Chair: Melinda R. L. Pon, BHP Minerals, SanFrancisco, CA 94104-1020 USA; R. Cortes, Santiago,Chile

10:30 AMInternational Health and Environmental Regulationsfor Metals: New Challenges for Copper: RicardoBadilla-Ohlbaum1; Gustavo F. Lagos2; 1Chilean Min-ing & Metallurgy Research Centre (CIMM), Avda.Parque A Rabat 6500, Vitacura, Santiago, Chile;2Catholic University of Chile, Ctr. for Mining, Avda.Vicuña Mackenna 4860, Macul, Santiago, Chile Copper has been used by man for a very longtime and unlike certain other metals, it is an essentialelement for life. Its toxicity arises both from a deficitand excess copper exposure/intake. The focus of thecurrent discussions in countries of the European Union(EU) and in some USA States, is based on the con-cerns, independent of the scientific facts and the eco-nomic status of these claims, of the negative influ-ence of copper and other metals on health and theenvironment. These discussions have influenced thenew regulations of copper in drinking water, and theapproach to regulate the appropriate levels of cop-per in surface water, soils and sediments. To illustratethe challenges ahead for copper, the evidence bywhich the current US Environmental ProtectionAgency (USEPA), the World Health Organization(WHO) and EU recommendation and regulations re-garding copper in drinking water have been derivedis presented and discussed. The gaps between thedemands for new standards of health and the envi-ronment and the practical scientific tools to achievethese goals are presented, and the need to developnew regulating paradigms is also illustrated. The in-troduction of methodologies for the regulation of es-sential elements and acute inorganic substances indrinking water is discussed, as well as the status of thepresent approach contained in the International Pro-gram of Chemical Safety Environmental Health Crite-ria, (EHC) Nϒ 170. The impact of the possible restric-tions on the use of copper in the EU because of healthand environmental concerns in terms of the world mar-ket for copper is discussed.

10:55 AMHuman Health Risk Assessment: An Ever-Moving Tar-get: Jenifer S. Heath1; 1URS Greiner Woodward-Clyde,4582 South Ulster St., Suite 1000, Denver, CO 80237 USA Human health risk assessments can be used in minepermitting, and are frequently used to investigate ar-eas of potential contamination and as a basis forremediation decision making while some states andUS Environmental Protection Agency (USEPA) Regionshave their own guidance for the conduct of humanhealth risk assessments, USEPA Headquarters guidanceand the underlying science are changing and ad-vancing rapidly. Even outside the US, USEPA guidancecan affect risk assessment costs and conclusions,

which in turn can affect cleanup costs or permittingoptions. This paper summarizes recent USEPA guid-ance and scientific evidence related to human healthrisk assessment for mining sites. This paper is designedfor non-risk assessors, and so focuses on the potentialapplications and implications of the new guidancerather than the mathematical and theoretical details.

11:20 AMThe Development of Environmental Regulations in Po-land and Its Influence on the Copper Industry: Hel-ena Byrdziak1; Jerzy Dobrzanski1; Jan Garbaczewski1;1KGHM Polska Miedz S.A., ul. M.Curie-Sklodowskiej 48,Lubin 59-300 Poland KGHM Polska Miedz S.A. is a significant Europeancopper producer with production of 447,000 mtpy,operating three underground mines and three smelt-ers. The company has been involved for years in en-vironmental activity, which was stimulated not onlyby the company itself, but by the development ofenvironmental regulations as well. The first set of regu-lations, concerning water protection, was establishedin Poland in 1974, while a comprehensive environ-mental law was passed in 1980. This law in generalrequires industry to submit all data of environmentalsignificance to the local authorities. Based on thisdata, they establish limits concerning emissions intothe air, water and ground, the amount of wastes pro-duced and the means of their disposal. A companyhas to pay fees for each tonne of emitted substancesand stored wastes. When the emission of a substanceexceeds the limit, the company has to pay a penaltywhich is about ten times higher than the fees. Thisapproach in general is effective because it forcescompanies toward reduction of their emissions. Theproblem is that the law is constantly subject to changeand is becoming not only more restrictive but is in-volving more and more bureaucracy.

11:45 AMThe New Paradigm: ISO 14000 and its Place in Regu-latory Reform: Robert A. Reiley1; 1Office of ChiefCounsel, Dept. of Environ. Protect., Rachel CarsonState Office Bldg., Harrisburg, PA 17961 USA Under the traditional environmental paradigm, in-dustry, stakeholders, and government impact theenvironment through production, consumption, andregulation. For more than twenty years, this paradigmhas survived more or less unchallenged. Environmen-tal action has followed a typical pattern: industrypollutes, the public clamors, government enacts leg-islation, and industry expenditures for pollution-con-trol equipment soar. In the 1990’s, many groups real-ize that command-and-control techniques may notbe the most effective method of dealing with envi-ronmental issues in the new millennium. The need forregulatory reform became apparent in the 1980’s af-ter an accident at the Union Carbide plant in Bhopal,India. In addition, the prospects of an integrated Eu-ropean market and increased global trade sparkeda need for common standards regarding the produc-tion of goods and services, which led to the adop-tion of the International Standards Organization (ISO)9000 Quality Standards. These factors, and others, trig-gered the development of the Environmental Man-agement System (EMS). Over the past decade, coun-try-and industry-specific EMSs were developed. How-ever, the ISO realized the need for a single, interna-

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tionally recognized standard that would be workablefor any type organization. The goal of this standardis to promote economic competitiveness, removetrade barriers, and promote environmental protec-tion. To this end, the ISO 14000 Standards were devel-oped to provide business with a structure for manag-ing environmental impacts. This article argues that anew paradigm has begun to transcend the old. Pro-tection of the environment if shifting from “govern-ment drivers” to “market drivers”. This shift means thatindustry and stakeholders, instead of government, aretaking the lead to develop ways to protect the envi-ronment. This article also argues that government canuse this new paradigm, in a time of declining bud-gets and regulatory reform, to continue to protectthe environment through increased compliance moni-toring and rigorous enforcement. Specifically, the ISO14000 Standards can allow the government to reducecompliance costs, streamline permit and reporting re-quirements, and provide business with regulatory flex-ibility. Finally, this article argues that ISO 14000 will becentral to the regulatory reform effort, because it canbe internally implemented with little need for legisla-tive intervention.

12:10 PMDevelopment and Implementation of a Common Cor-porate Management System for Safety and Healthat International Mining Operations: Kyle B. Dotson1;1BHP Copper, Dept. of Safety, Health and Environ.,550 California St., 5th Floor, San Francisco, CA 94104-1020 USA A common international safety and health man-agement system was developed. Analysis of selectedmajor safety and health management systems fromaround the world was conducted. Functional ele-ments of selected systems were grouped to identifycommon elements and key differences. Commonelements were subjected to qualitative judgments ofequivalency and then reconciled. With few excep-tions, differing elements were revised to achieve cul-tural neutrality. The resulting 98 system elements wereorganized according to the NOSA numbering andtitle scheme. System summaries were produced inSpanish and English. A pre-implementation self-assess-ment evaluated conformance in three distinct cul-tures. The consensus 98 element system was internallynamed the BHP Copper Five Star Safety System Per-formance Management Guidelines. Development ofa common system within an organization with inter-national operations can enhance the ability of thestaff function to share resources, programs and sub-system improvements and thereby increasingly pro-tect workers. Common systems can increase the levelof management support by demonstrating increasedcompatibility of the safety and health managementfunction with traditional business objectives. Safety pro-fessionals, industrial and occupational hygienists, busi-ness managers and the safety and health of workerswill benefit from further development and articula-tion of common systems for safety and health man-agement.

Hydrometallurgy: Electrowinning

Wednesday AM Room: HopiOctober 13, 1999 Location: Pointe Hilton Resort

Session Chair: Robert Washnock, Silver Bell MiningL.L.C., Marana, AZ 85653 USA

10:30 AMImproved Copper Electrowinning Operations UsingWrought Pb-Ca-Sn Anodes: R. David Prengaman1;Andres Siegmund1; 1RSR Technologies, Inc., 2777Stemmons Freeway, Suite1800, Dallas, TX 75207 USA Wrought lead-calcium-tin anodes developed byRSR Corporation have improved the performancecompared with the other lead alloy anodes. Theseanodes have been in continuous service at variouslocations around the world for as long as fourteenyears. Calcium provides mechanical strength to theanode to prevent the deformation while tin increasesthe mechanical strength, reduces the rate of corro-sion, prevents the formation of non-conducting lay-ers on the anode surface, and dramatically improvesthe conductivity of the anode. Tin is also instrumentalin developing the unique rolled structure of the an-ode which leads to the reduced rates of corrosion,longer life, and improved oxygen evolution. Cobaltadditions to the electrolyte further enhance the oxy-gen evolution and improve the anode life. Highercurrent densities and higher operating temperaturesreduce the anode life. The unique patented methodof attaching the rolled anode sheet to the bus barsubstantially reduces the resistance of this importantjoint and offers the substantial savings in power overthe life of anode.

10:55 AMElectrocatalytic Titanium Mesh Surfaces Combinedwith Standard Lead Substrates for Process Improve-ments and Power Savings in Copper Electrowinning:Kenneth L. Hardee1; Carl W. Brown1; 1ELTECH SystemsCorporation, Research Dept., 625 East St., FairportHarbor, OH 44077 USA A recent development has emerged which pro-duces a retrofittable low cost anode by attachingdisposable, electrocatalytically active titanium meshover the existing lead anodes. The coated titaniummesh anode operates at potentials of several hun-dred millivolts lower than the lead anode, providingsignificant power savings. The exposed lead surfacesare stabilized since most of the current flows throughthe titanium mesh. With the minimal lead corrosion,the sludge formation is virtually eliminated and thepurity of the plated copper is greatly enhanced. Fur-ther savings may be realized by the elimination ofnon-essential chemicals such as cobalt. Since thecombination anode is stable and uniform, the platedcopper is also more uniform with minimal formationof dendrites, reducing the shorting. Full-size anodeshave been tested for over 6 months in commercialcopper electrowinning cells. The laboratory and fieldperformance of the stabilized lead anode will be re-

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viewed, including the voltage characteristics, the leadstability and the copper cathode purity.

11:20 AMThe Corrosion of Lead Anodes in Copper Electrowin-ning: G. Cifuentes1; J. Simpson1; L. Cifuentes2; G.Crisostomo2; 1Universidad de Santiago, Depto. Ingen-ieria Metalúrgicia, Av.B. O’Higgins 3363, Santiago,Chile; 2Universidad de Chile, Depto Inenieria deMinas, Tupper 2069, Santiago, Chile When the applied current is interrupted in a cop-per electrowinning plant, and then is back in opera-tion, the lead anodes tend to corrode. In order todecrease the corrosion, the damage protective(“back up”) anodic currents are applied during theperiod of interruption. The current work aims to es-tablish the effect of the concentrations of sulphuricacid, copper and cobalt on the anode corrosion, toquantify the effect of various anodic protection lev-els on the anode corrosion, to quantify the effect ofvarious anodic protection levels on the anode corro-sion and to propose a method to select the appro-priate protective current density value.

11:45 AMMerrlin Composite Anodes for Copper Electrowinning:Marion Dattilo1; L. J. Lutz1; 1Merrlin, L.L.C., 107500 CR2000, P.O. Box 184, Rolla, MO 65402-0184 USA Research has been conducted over the past threeyears using the composite anodes versus the lead alloyanodes. The Merrlin composite anodes have shownthe improved performance in copper electrowinningversus the lead-calcium-tin anodes. Using the com-posite anodes a 100-150 mV reduction in anodeoverpotential has been observed versus the lead al-loy anodes in sulfuric acid electrolyte. The compositecoating has excellent corrosion inhibiting properties,and reduces or eliminates the formation of manga-nese oxide scale. Laboratory evidences indicate thatthe use of these composite anodes enhances the pro-cess of electrowinning by improving the lead alloycorrosion resistance, lowers the electrode potential,reduces the need for cobalt addition, eliminates theanode cleaning, and reduces the generation of acidmist. Field tests are underway.

12:10 PMNew Anode Compositions for Copper Electrowinningand Copper Electrodeposition at High Current Den-sity: Jean-Luc Delplancke1; René Winand1; Jean-PaulGueneau De Mussy2; Antonio Pagliero2; 1UniversitéLibre de Bruxelles, Metallu. Electrochem. CP165, 50Ave. F.D. Roosevelt, Bruxelles B-1050 Belgium;2Universidad de Concepción, Dept. de IngenieriaMetalúrgica, Facultad de Ingenieria, Casilla 53-C,Concepción, Chile During copper electrowinning in sulphate electro-lyte, intense oxygen evolution takes place at the an-ode. Lead alloy anodes are progressively replacedby dimensionally stable anodes in order to avoid thecathode contamination by dissolved lead. Theelectroactive coating of these anodes has to be ascheap as possible, adherent to the substrate, elec-trochemically stable and has to be efficient at highcurrent density and high temperature. This require-ment is even demanding in case of copper elec-trodeposition for the production of thin copper foilsfor the electronic industry. The production of thin

(20mm thick) copper foils for the printed circuit boardsrequires high purity copper electrodeposited at acurrent density as high as 7,000 A/m2. The choice of along term coating composition is driven by econom-ics. The purpose of this paper is mainly to review theanode compositions suitable for copper electrowin-ning and for copper electrodeposition at high cur-rent density. A short description of preliminary resultsobtained with a new anode coating on a titaniumsubstrate is also presented.

Pyrometallurgy-Operations: Session VI

Wednesday AM Room: EstrellaOctober 13, 1999 Location: Pointe Hilton Resort

Session Chair: Eric Partelpoeg, The Winters Com-pany, Tucson, AZ 85711 USA; William Davenport,University of Arizona, Dept. of Mats. Sci. and Eng.,Tuscon, AZ 85721 USA

10:30 AMRevising Copper Converter History: A Metallurgical“Whodunit”: Larry M. Southwick1; 1L. M. Southwick &Associates, 992 Marion Ave., Suite 306, Cincinnati, OH45229 USA Pneumatic converting (Bessermerizing) of iron revo-lutionized the steel industry. Bessermerizing of copper(conversion of copper sulfide matte to copper metal)was proposed at almost the same time, but it wasslow in being accepted. The differences between ironand copper converting were great and technicalproblems were substantial. It took 25 years for the pro-cess to become viable and another 25 years beforea truly economical solution was found. A major eco-nomical and productivity problem was the short lifefor converter refractory linings. The first converters hadacid (silica) linings, which were quickly consumedsince silica was a flux for the process. Converters hadto be relined at least once per day, a laboriously ex-pensive manual process with only the most rudimen-tary mechanical aids available to assist. The industrywas revolutionized almost overnight when finally aviable basic (magnesite) lining was developed. Thislasted hundreds of days versus less than one, leadingto converters that were easier to operate and whichhandled larger charges. This change occurred afterW. H. Peirce and E.A.C. Smith, with support from theGuggenheim interests, successfully operated a basiclined converter in a copper refinery in Baltimore. WhilePeirce and Smith are generally given credit for thedevelopment and explosive acceptance of this idea,a Pittsburgh industrialist, Ralph M. Baggaley, workingin an independent smelter in Butte, Montana, success-fully built and operated a basic lined converter fouryears before they did. In fact, the early support forPeirce and Smith likely occurred because Guggen-heim’s staff were encouraged after thoroughly exam-ining Baggaley on his earlier successes. The questionsof technology primacy between Baggaley andPeirce/Smith are ironically similar to those betweenWm. Kelly and Bessemer in converting iron to steel.

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This paper will review what Baggaley (and other earlyresearchers) accomplished, examine why he (or they)did not receive credit equal to Peirce and Smith andexplore what his (their) place should be in the devel-opment of successful basic linings. More suspects thana Victorian Whodunit.

10:55 AMDevelopment of New Bath Smelting Technology atMines Gaspe: J. F. Leroux1; B. Langlois1; Y. Massé1; X.J. Guo2; P. J. Mackey2; 1Mines Gaspé, Murdochville,Québec, Canada G0E 1W0; 2Noranda TechnologyCenter, 240 Hymus Blvd., Pointe Claire, Québec,Canada H9R 1G5 The Gaspe smelter at Murdochville, Québec,Canada introduced concentrate injection into elon-gated Peirce-Smith converters sized 1.96m x 12.5m (13ft. by 41 ft.) in 1996, and commissioned a large, con-verter-like bath smelting vessel in April 1998. The newvessel, which is sized 4.27m x 16.15m. (14ft. by 53ft.)has several interesting features designed to effectivelyutilize bath smelting technology for the requirementsof the Gaspe smelter. For example, the vessel canoperate on concentrate injection at upwards of 60-80 tph rate on an instantaneous basis, can operateas a large Peirce-Smith converter, while it is also fittedwith matte and slag tapholes much akin to NorandaProcess reactor, and includes a novel cold chargeaddition system. The new technology will eventuallyallow the capacity of the plant to increase from about300,000 tonnes of concentrate per year to over 350,000tonnes of concentrate per year while improving sul-fur capture.

11:20 AMConverter Operation at BHP San Manuel Smelter: T.W. Gonzales1; Darren Snashall1; Ovidiu Pasca1; Rob-ert David1; 1BHP San Manuel Smelter, P.O. Box M, SanManuel, AZ 85731 USA The BHP San Manuel Smelter operates anOutokumpu Oy flash furnace, conventional Pierce-Smith converters, anode casting facilities, and twodouble contact sulfuric acid plants. The flash furnacewas commissioned in July 1988 and since then, thesmelting capacity has been continuously increasedto 30% above design. The converter operation waschallenged to process larger amounts of matte withexisting capacity. Utilization of industrial technologi-cal improvements and people technology trans-formed the Converter Department from a constraintto easily accommodate the new demonstrated flashfurnace capacity. This technology also increased sec-ondary consumption, converter campaign life, andreduced operating costs. This paper will describe theimportant Converter Department achievements in thepast five years.

11:45 AMConcentrate Injection and Oxygen Enrichment inPeirce Smith Converters at Noranda’s AltonorteSmelter: Ernest D. Mast1; Jorge Arr ián V.1; JuanBenavides V.1; 1Fundición Altonorte, Avenida Anto-nio Rendic 5032, Antofagasta, II Región, Chile Noranda’s Altonorte custom smelter, located in the2nd region of Chile, 20 kilometres southeast of thecity of Antofagasta, started operations in 1993. Pres-ently, 1150 tonnes per day of new feed are smeltedwith an 85% sulphur capture. An oxy-fuel reverbera-

tory furnace produces a 48%- 55% copper matte thatis treated in 13 ft. x 36 ft.(3.96m x 10.97m) Pierce-SmithConverters (two hot and one blowing). Up to thirtypercent of the new concentrate is smelted via dryconcentrate injection into the converters. This paperreviews the development of the concentrate dryingand injection system, and oxygen enrichment atAltonorte from start-up in 1995 to the present time.The relationship between oxygen enrichment andconcentrate injection is reviewed from a theoreticaland practical standpoint. Concentrate injection hasimproved the smelter’s productivity and added flex-ibility to the operations. Due to the relatively highmatte grades and the subsequent short convertingtimes, maintaining consistent operations was difficultat times and the smelter has gone through a learningcurve. Plant operating results and experiences arepresented on the impact of concentrate injection inrelation to: feed treatment, blowing times, revert gen-eration, slag quality and refractory wear.

12:10 PMRefractory Performance in Peirce-Smith Converters atBHP San Manuel Smelter: T. W. Gonzales1; A. J. Rigby2;Ovidiu Pasca3; 1Hot Metals, P.O. Box M, San Manuel,AZ 85731 USA; 2NARCO Canada, Inc., 4355 FairviewSt., Burlington, Ontario, Canada L7R 3Y7; 3ConverterDept., P.O. Box M, San Manuel, AZ 85731 USA The refractory performance of Peirce-Smith con-verters is considered to be mainly determined by ef-fects of process control and refractory installationdesign. BHP Copper has shown that, over the last fouryears, considerable improvements in tuyere line lifecan be affected by maintaining a uniform tempera-ture in the operating converter and by ensuring suffi-cient and specific placement of expansion allowancein the construction of the refractory brickwork. A com-bination of optimized crane availability, rapid mattetransfer, converter operating practices, new refrac-tory installation techniques and applications has mini-mized out-of stack time. In addition, larger diametertuyere pipes and hard piping have increased blow-ing rates and lowered cycle times, which has resultedin a tuyere line performance in excess of 62,500 tonnesof blister copper before maintenance is required. Thispaper discusses the refractory installation designchanges that were made to increase tuyere line life.

12:35 PMUse of Microporous Insulation in Copper Holding Fur-naces at BHP Copper, San Manuel, AZ: Iain B.Mackenzie1; Ovidiu Pasca2; Arsenio Enriquez2; A. J.Rigby3; 1Microtherm, Inc., P.O. Box 62088, Burlington,Ontario L7R 4K2 Canada; 2BHP Copper, 200 S.Redington Rd., P.O. Box M, San Manuel, AZ 85631 USA;3NARCO Canada, Inc., 4355 Fairview St., Burlington,Ontario L7R 3Y7 Canada In 1997, a thin layer of Microtherm Microporous In-sulation was used to replace fireclay brick behind themagnesia/chrome working lining in #5 refining fur-nace at BHP’s San Manuel AZ smelter. A 23ϒC reduc-tion in shell temperature was obtained, together witha large increase in the working capacity of the ves-sel. There was no sign of metal penetration as a resultof the increased insulation. Following these highlyfavorable results, BHP has introduced this product intoall of their refining furnaces.

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Smelting: Technology Development,Process Modeling and Fundamentals:Fundamental Studies and TechnologyDevelopment - I

Wednesday AM Room: GoldwaterOctober 13, 1999 Location: Pointe Hilton Resort

Session Chairs: Mark Schlesinger, University ofMissouri-Rolla, Dept. of Metall. Eng., 1870 MinerCircle, Rolla, MO 65409-0340 USA; Igor Wilkomirsky,Universidad de Concepción, Dept. Ing.Metalúrgica, Edmundo Larenas 270, Concepción,Chile

10:30 AMDynamic Modeling of Copper Losses in Slag: J. W.Matousek, 8547 E. Arapahoe Rd., #J149, GreenwoodVillage, CO 80111-1430 USA Copper losses in smelter slags are typically normal-ized with some form of the distribution coefficient,written as the ratio of the weight percent assays ofmetal in slag to the metal in matte or its inverse: L(s/m) = %(Cu)/%[Cu] or L(m/s) = %[Cu]/%(Cu). How-ever, this simple approach ignores the dynamics ofthe smelting process. It overlooks the effect of thechemical work done in producing a given mattegrade from concentrates of different grades—or froma single concentrate blended with varying quantitiesof copper bearing precipitates or reverts. This paperexamines the combined influences of matte gradeand the work done in smelting on the copper con-tent of smelting furnace slags. A simple model for therelationship is proposed.

10:55 AMDissolution of Copper and Nickel in FeOX-SiO2 BaseSlag Equilibrated with Copper-Nickel-Iron Matte un-der High Partial Pressures of SO2: Jonkion MarcosFont1; Mitsuhisa Hino1; Kimio Itagaki1; GhasemRoghani2; 1Tohoku University, Instit. for Adv. Mats.Proc., Katahira 2-1-1, Sendai, Miyagi, Aoba Ku 980-8577 Japan; 2The University of Queensland, Dept. ofMining, Min. & Mats. Eng., Brisbane QLD 4072 Austra-lia As a comprehensive contribution to the under-standing of oxygen-blowing of matte smelting, thecopper and nickel solubilities between the FeOx-SiO2-MgO slag with saturated Si02 and the Cu2S-Ni3S2-FeSmatte with the NCu /(NCu+ NNi) of 1, 0.75, 0.5, 0.25 and0, in a MgO crucible were investigated at 1573 K un-der controlled partial pressures of SO2 at 0. 1, 0.5 andI atm. The partial pressures of SO2, S2 and O2 were con-trolled by using an Ar-S02-S2 gas mixture after passingthrough a sulfur reservoir. It was clarified that, at agiven matte grade, the solubility of copper in the slagwas independent of pso2 while that of nickel increasedwith increasing pso2. This notable difference was con-sidered to be ascribable to the chemical formulas ofthe monometallic sulfides in which one copper atomcombines with 1/2 sulfur atom while one nickel atomcombines with 2/3 sulfur atom. It was also clarifiedthat, at a given iron content in the matte, the po2

and ps2 were independent of the matte species. Thiswas ascribable to aFeS in the matte, which was inde-pendent of the matte composition, NCu/(NCu+NNi), ata given iron content in the matte.

11:20 AMDevelopment of the El Teniente Slag Cleaning Process:Gerardo Achurra1; P. Echeverria1; A. Warczok2; G.Riveros2; C. M. Diaz2; T. A. Utigard3; 1Codelco Chile,El Teniente Div., Millan 1040, Rancagua, Chile;2Universidad de Chile, Dept. Ingenieria de Minas, Av.Tupper 2069, Casilla 2777, Santiago, Chile; 3Universityof Toronto, Dept. of Metall. and Mats. Sci., 184 Col-lege St., Toronto, Ontario, Canada M5S 3E4 The products of the smelting of copper concen-trates in an El Teniente Converter (CT) are: a highgrade matte, analyzing 74-76% Cu; and a highly oxi-dized slag, typically containing 15-20% Fe304 and 4-10% Cu. The El Teniente Division of Codelco-Chile hasdeveloped a slag reduction-cleaning process, that ispractised in a tilting, horizontal furnace, to recovercopper from these slags. The El Teniente slag clean-ing process has been successfully implemented at theEl Teniente Caletones smelter and various other smelt-ers in Chile. Today, eight such slag cleaning furnaces,each with a capacity of 800-1000 tonnes/day, are inoperation in Chile. This paper discusses basic labora-tory research and industrial tests that led to substan-tial reductions in the slag cleaning cycle time andthe specific consumption of fuel and reductants. Si-multaneously, the slag cleaning off-gas quality wasimproved. Based on the experimental results, recom-mendations were made to improve the practice ofthe El Teniente slag cleaning process. The recom-mended modifications have been fully implementedat the Caletones smelter.

11:45 AMEffect of ZnO, Cu2S and CaO on the Viscosity of Smelt-ing and Cleaning Slags in Copper PyrometallurgicalProcesses: C. M. Acuña1; C. Hú1; J. Jara1; F. Parada2;1Codelco Chile, Chuquicamata Div., SubgerenciaFundición de Concentrados, Chuquicamata, Chile;2Universidad de Concepción, Depto. IngenieriaMetalúrgica, Casilla 53 C Correo 3, Concepción,Chile Copper losses in slags are of great concern, spe-cially in smelting and slag cleaning processes. It iswidely accepted that the suspension of metallic cop-per and matte droplets is strongly affected by the vis-cosity of the slag. The Chuquicamata Division ofCodelco Chile produces concentrates high in zinc,an element which reports mainly to the slag phase.The ZnO may affect the viscosity and therefore thecopper losses. This work aimed to investigate the ef-fect of lime to control the viscosity of slags, and inturn to control the copper losses. By using the experi-mental viscosity data and the Stoke’s law, the set-tling rate of matte prills in various slags was estimated.The results indicate the possibility of increasing therecovery of copper and/or decrease the process time.

12:10 PMThe Effect of Minor Components and Flux Additionson the Liquidus Temperatures of the MulticomponentIron Silicate Slags: Florian Kongoli1; Ian McBow1;1Flogen Technologies, P.O. Box 49529, C.P. Du Musee,Montreal, Québec, Canada H3T2A5

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Minor components and flux additions can modifythe liquidus temperatures of multicomponent slags.In industrial practice, slags with various levels of mi-nor components require various flux additions in or-der to achieve the lowest possible liquidus tempera-ture. The prediction and the optimization of these com-binations can decrease the cost of the overall pro-cess. In this work the effect of several minor compo-nents and flux additions such as A12 03, MgO, andCaO, on the liquidus temperatures of multicompo-nent iron-silicate slags has been analyzed in terms ofa thermodynamic model. Various simple isothermaland non-isothermal diagrams are presented. Thesediagrams can be used directly by the process opera-tors to define the optimum conditions under whichthe fluxes can be used to achieve the desired slagliquidus temperatures.

12:35 PMAutomatic Mineralogical Analysis of Copper Slags:E. Almendras de Siegel1; P. D. Siegel2; 1University ofChile, Dept. of Mining Eng., Tupper 2069, Santiago,Chile; 2University of Santiago, Departo. de Ingenieriade Minas, Av. B., O’Higgins 3363, Santiago, Chile Pyrometallurgical processes have the thermody-namic capability of treating complex and dirty oresand concentrates to produce high purity metals andinert slags. Modern pyrometallurgical processes areenvironmentally sound and comparative with otherprocesses. However, there is still a need for sensorsand other practical tools that permit a rapid evalua-tion of the performance of these processes. In orderto contribute to satisfying this fundamental require-ment, the authors developed the IDENT.LA softwarethat permits the automatic mineralogical analysesinorganic materials, including the final and interme-diate products of pyrometallurgical processes. Thistechnique allows determining the grain size distribu-tion of mineralized inclusions, the surface relationsbetween metallic phases, and conducting modalanalyses of the essential phases that are present inthe samples. Three basic automatic operations areperformed: creating a representative image of thesample; identifying the metallic and non-metallicphases; and measuring the features of the resultingimage. The results are used to evaluate the perfor-mance of pyrometallurgical and other processes. Inthis paper, the authors discuss the application of thetechnique to a sample of slag from a slag cleaningprocess that uses a carbonaceous reductant. In thiscase, process performance impacts not only on theefficient reduction of the slag magnetite and on cop-per recovery but also on the quality of the processoff-gas. The mineralogical analysis of the slag is avaluable tool in assessing process performance andin recommending changes of operating conditions.

Electrorefining: Reactions DuringElectrorefining

Wednesday PM Room: IndigoOctober 13, 1999 Location: Pointe Hilton Resort

Session Chairs: C. Anderson, CAMP of MontanaTech., Butte, MT 59701 USA; M. Van Camp, UMResearch, Watertorenstraat 331, B-2250 Olen, Bel-gium

2:00 PMAnodic Slimes Characteristics and Behaviour in Cop-per Refining: G. Cifuentes1; S. Hernádez1; P. Navarro1;J. Simpson1; C. Reyes1; A. Naranjo1; L. Tapia1; E.Correa2; N. Cornejo2; R. Abel2; 1Universidad deSantiago de Chile, Depto. de Ingeniería Metalúrgica,Av. B.O’Higgins 3363, Santiago, Chile; 2Fundición yRefinería Electrolitica Ventanas - ENAMI, Carretera F-30 E N° 58270 Ventanas, Comuna Puchuncavi, V Re-gión, Chile It is known that the cathode purity and the electro-lyte treatment are affected by the solids present inthe electrolyte. Anodic slimes properties (e.g., chemi-cal composition, crystalline composition, sedimenta-tion) were studied in copper electrorefining. Theseproperties were modified through anodic composi-tion and current density. In this investigation, we haveworked with anode material from the Ventana Smelt-ing, Hernán Videla Lira Smelting (ex–Paipote) of ENAMI(National Mining Company) and El Teniente Smelt-ing of Codelco-Chile (National Corporation of Cop-per of Chile). The characterization of the anodic slimeswas done as a function of current density and an-odic composition.

2:25 PMA Mineralogical Study of the Deportment of Impuri-ties During the Electrorefining of Secondary CopperAnodes: J. E. Dutrizac1; T. T. Chen1; 1CANMET, 555Booth St., Ottawa Canada K1A 0G1 Secondary copper anodes are generally rich in Sn,Pb, Ni and Sb, but are notably deficient in Se, Te andAg. In the secondary copper anodes, most of the Ni,virtually all of the Ag, slightly more than one-fifth ofthe Pb, about one-third of the As and Sb, and ap-proximately one-tenth of the Sn are in solid solution inthe copper. The remaining impurity contents occuras 1-5 µm grain-boundary inclusions in the anodes,and these are mainly Cu2O, SnO2, Cu-Pb-As-Sb-Bioxide, Pb-Sb oxide, Sn-Ni-Zn oxide, Cu-Sn-Ni oxide,Cu-Sb-Ni oxide (Kupferglimmer) and trace Cu2(Se,Te).Barium sulphate, which originates from the mold washused in casting, is also present in the anodes. Duringelectrorefining, the BaSO4, SnO2, Pb-Sb oxide, Sn-Ni-Zn oxide, Cu-Sn-Ni oxide and Cu-Sb-Ni oxide inclu-sions are liberated and accumulate in the slimes layer.Solid solution Ni dissolves and the Ni accumulates inthe electrolyte. Solid solution Sn and Pb dissolve, butpartly reprecipitate as Sn arsenate and PbSO4, respec-tively. Solid solution Ag dissolves but rapidly reacts toform Ag2(Se,Te), Ag powder, Ag-bearing Cu2O,(Cu,Ag)SO4 or a complex oxidate phase. Partial dis-

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solution of the Cu-Pb-As-Sb-Bi oxide particles takesplace; the Pb component is converted to PbSO4,whereas Cu, As, Sb and Bi dissolve. The reacted par-ticles retain the morphology of the original Cu-Pb-As-Sb-Bi oxide phase. Some of the solubilized As, Sband Bi remains in solution, but much reprecipitates asSbAsO4, As-Sb-Bi oxide, and as a poorly definedoxidate phase which consists mostly of Cu-Ag-Pb ar-senate-sulphate. The high Sn contents of secondarycopper anodes do not seem to affect the behaviourof the anodes during electrorefining.

2:50 PMAdditive Monitoring and Interactions during CopperElectroprocessing: D. W. Collins1; J. B. Hiskey1; 1Uni-versity of Arizona, Department of Materials, Scienceand Engineering, P.O. Box 210012, Tucson, AZ 85721USA Several organic and inorganic substances arewidely used to control deposit structure and morphol-ogy during the electroprocessing of copper. Meth-ods for monitoring the levels of thiourea, glue andguar gum during electrorefining and electrowinninghave been successfully developed under the tradenames of Reatrol and CollaMat. Other instrumentalmethods have been developed for additives anddecomposition products associated with the electro-plating of copper and other metals. Generally, thesemethods have been found to be either insufficientlysensitive or lacking in the desired selectivity for someor all of the additives. These procedures have mostlyemployed DC techniques; i.e., cyclic voltammetry,Tafel analysis, etc. In this work, chronopotentiometry(CP) and AC voltammetry were used to examine theinteraction of glue, guar gum, thiourea and chlorideduring the electroplating of copper onto a platinumelectrode. In addition, the interactions between theadditives have been explored. It was found that gluein pure electrolyte (H2SO4 and CuSO4 only) had noeffect on the chronopotentiogram. Glue was onlyactive if chloride ions were present. The addition ofthiourea resulted in several different chronopotentio-grams depending on the presence of either chlorideor chloride and glue. Thiourea used in conjunctionwith glue and chloride showed a significant increasein the polarization during copper deposition whencompared to the electrolyte containing only glue andchloride. The use of a modified channel electrodefurther increased the sensitivity of CP. The use of ACvoltammetry was explored as a technique to monitorsome of the additives. AC voltammograms havemore spectral detail then their DC counterparts andit is possible to monitor some of the additives at verylow concentrations with AC techniques.

3:15 PMThe Use of Electrodialysis for Separating and Concen-trating Chemical Species in Acidic Cu-Fe-As-Sb Elec-trolytes: L. Cifuentes1; G. Crisóstomo1; F. Alvarez2; J.Casas2; G. Cifuentes3; 1Universidad de Chile, Dept.Ingeniería de Minas, Tupper 2069, Santiago, Chile;2Universidad de Chile, Depto. Ingenieria Quimica,Beauchef 861, Santiago, Chile; 3Universidad deSantiago, Depto. Ingenier ia Metalúrgica, Av.BO’Higgins 3363, Santiago, Chile Electrodialysis (ED), i.e. a technique based on theeffects of electrically charged membranes on ions insolution in an electric field, has been applied to Cu-

Fe-As-Sb-H2SO4 electrolytes similar to those used incopper electrorefining and electrowinning opera-tions. The effects of current density, time and speciesconcentration have been studied in a batch ED cell.The technique has shown to be effective in concen-trating and separating a range of ions and points topossible new methods of treating copper electromet-allurgy effluents.

3:40 PM Break

4:10 PMThe Influence of Chloride and Glue on Copper Electro-crystallization on Titanium for Thin Film Applications:A. J. B. Dutra1; T. J. O’Keefe2; 1UFRJ, Metallurgical andMaterials Engineering Program, P.O. Box 68505, Riode Janeiro, RJ 21945-970 Brazil; 2University of Missouri-Rolla, Mats. Res. Ctr., Rolla, MO 65409-1170 USA Electrocrystallization studies were conducted in aconcentrated acid copper electrolyte to determinethe influence of chloride ions and glue on coppernucleation and on the structure of thin copper lay-ers. Electrochemical experiments allied to SEM andXRD examination were performed to characterize themechanism of nucleation of in the presence of addi-tives at 65°C. Results indicated that most of coppernucleation from a 83g dm-3 Cu2+ solution, with 140gdm-3 of H2SO4 is achieved in a matter of milliseconds.Although the presence of chloride and glue, at theconcentration levels tested, does not seem to sub-stantially modify the nucleation mechanism, the mor-phology, nuclei density and the copper film structureand orientation are changed by the presence of ad-ditives and electrolyte stirring.

4:35 PMNucleation and Initial Stages of Growth of CopperElectrodeposited on Anodized 304 Stainless Steel: M.Urda-Kiel1; L. Oniciu1; J. L. Delplancke2; R. Winand2;1University Babès-Bolyai, Chem. and Chemical Eng.,11, Arany Janos str. R 3400, Cluj-Napoca Romania;2Université Libre de Bruxelles, Dept. of Metall. &Electrochem., 50 Ave. F. D. Roosevelt, Brussels B-1050Belgium Stainless steel is increasingly used as a cathode start-ing sheet. It was shown earlier that even when de-positing copper on copper, a substrate-influencedzone appears in the deposit structure, followed by atransition zone and finally by the electrolysis-influ-enced structure. On copper, the substrate-influencedzone has a thickness of twenty micrometers and ontitanium, eventually more than fifty micrometers. Ini-tial nucleation and growth have a considerable in-fluence. In this paper, copper was deposited in achannel cell on four different 304 stainless steel sub-strates: mechanically polished and anodized, respec-tively, at 0, +400 and +800 mV/SHE in 1M H2SO4 at20°C. Copper was deposited under electrowinningconditions after solvent extraction (SX) (40 g/l Cu++,180 g/l H2SO4, 20 or 60°C). The results showed that,although Auger surface analyses of the substrateswere only slightly different one from another includ-ing the oxide thickness, nucleation and initial stagesof growth were very sensitive to the surface treatmentof the substrate. Potential step and current step meth-ods gave similar results: progressive nucleation fol-lowed by 3D diffusion controlled growth. The highestnucleation frequency was observed on stainless steel

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anodized at 0 mV/SHE, under various electrolysis con-ditions. The potential influence of these findings onindustrial practice is discussed.

5:00 PMThe Application of Copper Metallurgy in the Recov-ery of Secondary Precious Metals: C. Anderson1; T.Fayram2; M. Doolin3; 1Montana Tech, The Center forAdvanced Mineral and Metallurgical Processing, Rm.221, ELC Bldg., Butte, MT 59701 USA; 2UniField Eng.,Inc., 2626 Lillian Ave., Billings, MT 59101 USA; 3GD Re-sources, Inc., 450 Glendale Ave., Sparks, NV 89431 USA Most applications of copper metallurgy are gearedtowards primary production. However, as recyclingof materials is a growing industry, one future facilitywill rely on copper metallurgy as a means of process-ing precious metals. This paper will discuss the deri-vation of the proposed copper pyrometallurgical andelectrometallurgical unit operations to be utilized inindustrial recycling of secondary precious metals.

Environment, Health & Safety: Session II

Wednesday PM Room: CopperOctober 13, 1999 Location: Pointe Hilton Resort

Session Chairs: Norbet Piret, Piret & Stolberg Part-ners, Consulting Engs., Im Licht 12, Duisburg D-47279Germany; J. Solari, SGA Ibersis, Encomenderos 260,Piso 9, Las Condes, Santiago, Chile

2:00 PMEnvironmental Problems and Effluent Treatment in theChilean Copper Industry: S. H. Castro1; M. A.Sánchez1; F. Vergara1; 1University of Concepción,Dept. of Metallu. Eng., Clean Tech. Grp., P.O. Box 53-C, Concepción, Chile In 1997 Chile was the world’s largest copper mineproducer with around 3.4 million metric tonnes ofcopper. Conventional technology (conminution-flo-tation-smelting-converting-electrorefining) for coppersulfide ores was used. For copper oxidized ores hy-drometallurgical processes (heap leaching-solventextraction-electrowinning) were employed. Conse-quently, the most important waste effluents includeflotation tailings, gaseous emissions, smelter slags,acidic and alkaline wastewater, electrolytic sludges,solid residues from leaching, etc. The introduction ofstricter environmental regulations are forcing the Chil-ean industry to minimise the generation of waste andpromote cleaner production. Gas emissions such asSO2 and arsenic from smelters and process wastewa-ter are the major problems at this stage. The environ-mental impact assessment of gas emissions in all sixlargest smelters namely Chuquicamata, Caletones,Potrerillos, Ventanas, Paipote and Chagres led todesign a “decontamination plan.” The implementa-tion of this plan resulted in (i) the installation of sulfu-ric acid plants for SO2 abatement and (ii) the installa-tion of electrostatic precipitators to remove arsenicoxides condensed from cooling gases. The aim ofthis paper is (i) to describe the type of waste associ-ated to the various stages of the metallurgical pro-cesses and (ii) review the main abatement technolo-

gies used in medium and large size companies.

2:25 PMHernán Videla Lira Copper Smelter Fulfillment of Envi-ronmental Regulations: Jose A. Sanhueza1; OrlandoC. Rojas1; A. E. Balocchi1; 1Empresa Nacional DeMinería, Fundición Hernán Videla Lira, Copiaoó,Tercera Region, Chile The environmental regulations and terms issued bythe Chilean Government for all copper concentratesmelters have been a very important reason for per-mitting project developments that drastically decreasethe sulfur emissions due to the pirometallurgycal cop-per process. A remarkable case of the Hernán VidelaLira Copper smelter, located on the Copiaoó Valleyand very near some housing-sets of a city of high de-velopment, are described. Results of this project’simplementation of the control and reduction of offgas emissions, the control and monitoring system, thecommunity conflicts, and the strategy to comply withthe demands established by the state environmentalinstitutions, are presented.

2:50 PMArsenic Management in Copper Smelting: Norbert L.Piret1; 1Piret & Stolberg Partners, Consulting Engs., ImLicht 12, Duisburg D-47279 Germany During smelting of copper, arsenic in the feed re-ports to a large extent to the gas phase and someenters the anode copper. From the gas phase it istransferred during wet gas cleaning directly, or indi-rectly after dust processing, to aqueous solution. Dur-ing the electrorefining and anode slimes processing,the anode arsenic content is also transferred to aque-ous solution. Technology for the efficient removal ofarsenic from process streams and cleaning of aque-ous effluents is well established. However, the arsenic-bearing products, which thereby are generated, canvary widely in consistency, quality and quantity, fromlarge amounts of gypsum contaminated with water-soluble arsenic compounds to residues with high ar-senic content or arsenic products. Arsenic manage-ment in a copper smelter not only is involved with theduty of compliance to the gaseous and aqueousemissions standards but also should have as objec-tive the minimization of the generation of arsenic-bearing and, in general, heavy metal-bearing solidwaste. The present paper outlines options and theassociated economic aspects for minimization of ar-senic-bearing solid waste generation, for improve-ment of the environmental compatibility of the resi-dues to be deposited and for the production ofcommerciable arsenic compounds under appropri-ate market conditions.

3:15 PMPotential Use of Electron Beam Irradiation for Abate-ment of Lean Metallurgical Off-Gas Emissions: LoretoVillanueva1; L. S. Ahumada1; W. Ell ison2; A. G.Chmielewski3; Z. Zimek3; S. Bulka3; J. Licki4; 1ChileanNuclear Energy Commission, Amunategui 95, Casilla,Santiago 188-D Chile; 2Ellison Consultants, 4966 TallOaks Dr., Monrovia, MD 21770 USA; 3Institute ofNuclear Chemistry and Technology, Dorodna 16, War-saw 03-195 Poland; 4Institute of Nuclear Energy,Otwock, Swierk, Poland An investigation and evaluation has been per-formed to determine the potential utilization of elec-tron beam irradiation technology for sulfur oxides re-

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moval from reduced-S02-strength metallurgical gasesfrom copper smelters. These off-gases, though tooweak to be converted to usable, concentrated sulfu-ric acid by conventional means, are characterizedby S02 content higher than 2,000 ppm and a complexchemical composition, including high oxygen con-tent and its generation occurring in a cyclical, fluctu-ating pattern. This work was based on informationsupplied by principal smelter companies in Chile. Alaboratory facility with flow rate of 20 NM3/h andequipped with an electron accelerator of beam en-ergy 800 keV, has been used for testing. Influence onS02 removal efficiency of operational parameters suchas gas temperature, water vapor content, ammoniafeed ratio and irradiation dose was established. Themain conclusion of this work, from experimental labo-ratory tests as well as engineering studies, is that theElectron Beam Process (EBDS) is a cost-effective, simpleand appropriate chemical process means for emis-sion abatement. EBDS can, on a site-specific basis,adequately augment S02 removal to upgrade over-all abatement as required and in an optimal man-ner.

3:40 PM Break

4:10 PMUptake of Copper from Extremely Dilute Solutions byAlginate Sorbent Material: An Alternative for Environ-mental Control: J. P. Ibanez1; Y. Umetsu1; 1TohokuUniversity, Institute for Adv. Mats. Proc., Katahira 2-1-1, Aoba-ku, Sendai, Miyagi-ken 980-8577 Japan The uptake of copper from extremely dilute aque-ous solutions by alginate in the form of protonateddry alginate beads was investigated. Barium was usedto cross link the alginate forming the beads. The ef-fect of various experimental parameters such as pHand metal ions concentration on the uptake of cop-per were studied. The uptake was strongly depen-dent on the Cu-bearing solution pH up to a value of4.5. A removal of 100% was achieved when the initialconcentration of copper was as low as 8.0 mg/L. Themaximum uptake, i.e., the loading capacity, wasfound to be 167 mg of copper per g of beads. Themechanism governing the removal of copper wasfound to be ion exchange between protons of thealginate beads and cupric ions of the solution. Forthis ion exchange process a molar ratio, d[H+]/d[Cu2+], of 2.0 was determined. EPMA-EDX analysisof the Cu-loaded beads showed a uniform distribu-tion of the ions throughout the structure of the algi-nate, regardless the solution pH. This may suggest thatthis sorbent material is a porous ion exchanger hav-ing high permeability and capacity. The uptake ofcopper and of the heavy metals cadmium and zincby this sorbent is compared.

4:35 PMUse of Gracilaria Chilensis Biomass for Heavy MetalsAdsorption in a Mine Waste Water: F. Rios1; M.Sanchez1; F. Vergara1; 1University of Concepción,Dept. of Metallu. Eng., P.O. Box 53-C, Concepción,Chile Fundamental research, at laboratory scale, on thebiomass adsorption capacity of a liquid mining efflu-ent has been done. The biomass used correspondsto a Chilean seaweed called Gracilaria chilensis. Thewaste water effluent corresponds to clear water com-ing from thickeners of a Chilean copper mining op-

eration. The biomass was dried, washed, treated withan acid solution, and then reduced in size. A char-acterization of Zeta potential was made, findingnegative values in a wide pH range with a ZPC equalto 2.5 1. Adsorption tests were made in an agitatedsystem containing an artificial solution of CUS04 at acontrolled temperature of 25 degrees Celsius; also,the effect of pH over the copper absorbed was stud-ied. Maximal adsorption of copper was found at pHequal to 6, and the Langmuir model indicated val-ues for saturation of 52.08 mg/g and for standard freeenergy of about -21 KJ/mol. Kinetic adsorption wasvery high and fitted very well with a second ordermodel equation, finding that 90 percent of the ad-sorption occurred during the initial 10 minutes. Afterstoichiometric when I mol of copper is absorbed, 2mol hydrogen are released, showing that the mainmechanism to remove heavy metals is the ionic ex-change, and the seaweed ensures total discharge ofcopper absorbed when the pH value is about 1. Ex-periments done with real waste water from thicken-ers lead us to conclude that optimal results for cop-per and molybdenum adsorption are at pH around3.25 and the remaining treated water may be par-tially discharged into the water currents, thus show-ing that Gracilaria chilensis can be used to removeheavy metals easily from liquid effluents in the cop-per mining industry.

5:00 PMTailings Impoundments Management - The ZambianExperience: Godwin M. Beene1; Peter Chisanga1;Alexie Mpishi1; 1Zambia Consolidated Copper MinesLimited, P.O. Box 22000, Kitwe, Zambia Large scale mining operations started in Zambia in1913 and rapidly expanded during the post 1930 pe-riod with the opening of several mining and process-ing plants on the present Zambian Copperbelt. As aconsequence of poor tailings dumps design meth-ods at the start of the mines, and in view of stringentGovernment Legislation pertaining to environment inthe recent years, Nkana Mine has developed a uniquemethod of dump construction at its current tailingsdepository, Tailings Dam 15A. This method has en-abled the revegetation of the dump retaining wallswhile construction is still in progress, a situation whichwas not possible on the older dumps. Cowdung hasproved to be a superior fertilizer for providing plantnutrients on the tailings. The new method of dumpwalls construction and walls rainwater runoff drain-age system has almost eliminated tendency of gullyformation which is common on older dumps, as rain-fall on the Zambian Copperbelt comes in intense thun-derstorms. The decanted water from the dump is dis-charged to the natural environment in a controlledfashion after ensuring that it meets the Zambian Gov-ernment Statutory requirements.

5:25 PMSelecting an Economical and Safe Tailings Disposal:Han Ilhan1; Pedro Repetto1; 1URS Griener WoodardClyde, 4582 S. Ulster St. Pkwy., Ste. 1000, Denver, CO80237 USA This paper discusses and describes aspects of a costeffective and safe tailings impoundment selection. Inlight of the current low metal prices and recent tail-ings embankment failures around the world, it is be-coming extremely more important to develop tailings

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impoundment design that balance cost efficiencywith safety. The paper will present critical design com-ponents associated with a tailings impoundmentwhich need to be addressed during the planningphase. Procedures for identifying various tailings im-poundment alternatives, and evaluation and selec-tion of alternatives are presented.

5:50 PMThe Challenges Posed by Mine Closure in Chile:Marcelo E. Andia1; Gustavo E. Lagos1; Luke J.Danielson2; 1Catholic University of Chile, Ctr. for Min-ing, Avda. Vicuña, Mackenna 4860, Macul, Santiago,Chile; 2International Development Research Centre,Plaza Cagancha 1335, P.9, Casilla de Correo, Monte-video 6379 Uruguay In Chile, a significant amount of mining takes placein varied geographical environments. Mining activityextends from copper and gold deposits located inthe Atacama Desert 4.500 meters above sea level tounderground coal workings beneath the sea floor.This diversity in location and environment presentsmany challenges in the development of competitiveand environmentally sustainable mining activities. Animportant future issue will be how to close these minesin an appropriate way once economically exploit-able ore reserves have been exhausted. This poseschallenges for both the government and companiesalike, considering that Chilean law currently lackslegislation specific to mine closure. This paper exam-ines the risks associated with mine closure based oninternational experience, and identifies those risksspecific to Chilean regions. The main regions in Chilewhere mine closure legislation should be applied areidentified.

6:15 PMClosure or Abandonment of Mining Operations:Ximena Massone Quiroz1; 1Chilean Copper Commis-sion, Agustinas 1161, 4° Piso, Santiago, Chile Chile is the most important copper producer in theworld and the mining sector plays a key value in itseconomy. However, at present the country does nothave a satisfactory set of regulations about closureand restoration of mining operations. In our countrymany mining operations will, in the near future, shutdown their activities, therefore, it is of utmost impor-tance to elaborate and enforce a set of regulationsto prevent risks and to protect the environment. Thepresent study is focused on reviewing and analyzingthe existing national regulations about the closure ofmining operations and preparing a comparativeanalysis with other international regulations of coun-tries with mining experience. The final results of thestudy will be a legal proposal to regulate the closureof mining operations in Chile, aiming at minimizingthe potential environmental adverse impact, internal-izing the social costs by the relevant operators anddefining all aspects of liability for the environmentaldamage.

Hydrometallurgy: Electrowinning

Wednesday PM Room: HopiOctober 13, 1999 Location: Pointe Hilton Resort

Session Chairs: Kevin L. Purdy, Phelps DodgeMining Company, Process Tech. Ctr., Safford, AZ85546 USA; Douglas Robinson, DREMCO, Phoenix,AZ 85732 USA

2:00 PMImplementing Technology: Conversion of PhelpsDodge Morenci, Inc. Central EW Tankhouse from Cop-per Starter Sheets to Stainless Steel Technology: J. R.Addison1; B. J. Savage1; Joanna M. Robertson1; E. P.Kramer1; J. C. Stauffer1; 1Phelps Dodge Morenci, Inc.,4521 U.S. Highway 191, Morenci, AZ 85540 USA Commissioned in September 1987, the PhelpsDodge Morenci, Inc. (PDMI) Central Electrowinning(EW) Tankhouse has undergone two major expansionsin its eleven-year history. A third tankhouse renova-tion, which began in November 1998, entails com-plete conversion of the 548-cell facility from a cop-per starter sheet based operation to Mt. Isa Processstainless steel mother blank technology. This paperoutlines the operating history of the Central EWTankhouse and reviews the conversion process, therationale that led PDMI to undertake this project, anddescribes various design optimizations which havebeen implemented during the conversion.

2:25 PMCoulombimetric Reduction: An Evaluation Alternativefor Lead-Based Anode Corrosion: Antonio Pagliero1;Froilan Vergara1; Jean Luc Delplancke2; RenéWinand2; 1Universidad de Concepción, Dept. ofMetall. Eng., BP 53-C, Concepción, Chile; 2UniversiteLibre de Bruxelles, Metallu.-Electrochem. Dept.,Bruxelles B-1050 Belgium The coulombimetric reduction method has beenused as an evaluation technique for Pb-Ca-Sn an-ode corrosion in the LIX-SX-EW process. The proposedmethodology involves three consecutive steps, i.e.,cleaning, oxidation and reduction. They are carriedout in the same experimental unit, in solutions con-taining 180 g/L H2SO

4 with and without the addition ofcobalt. The authors have worked in a wide range ofoxidation current densities, from 150 to 500 A/m2 forin a period from 0.5 to 120 hours. It can be concludedfrom the results that there would be a linear relation-ship between the applied electrical charge I*T (Cou-lomb) and the anode corrosion expressed as trans-formed Pb mass (mg), for solutions with or withoutthe addition of cobalt. The exception is that for thelast one the corrosion rate is 5 times faster, which wasobserved for every layer. From the evaluation of dif-ferent corrosion layers, one can point out that its com-position is mainly in the form of sulphate. In the pres-ence of cobalt, about 67% of Pb would be as sul-phate (PbS04), about 27% as a basic oxide (PbO) andonly 6% as oxide Pb02 on the surface. From this result,it appears that great transformations occurred in the

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metal/sulphate interface. Without the addition ofcobalt, the proportion of oxide Pb02 on the surfaceincreased up to 11.5%. According to the previousstatement and considering that Pb was found mainlyas sulphate, the authors recommend its determina-tion be used as quality selection criterion. Its evalua-tion should be performed in the acid solutions with200 ppm cobalt addition at an oxidation current den-sity of 300 A/m2 for a period of 24 hours.

2:50 PMA Study of the Spouted-Bed Electrowinning of Cop-per: V. Jiricny1; A. Roy2; J. W. Evans2; 1Institute ofChemical Process Fundamentals, 165 02 Praha 6,Czech Republic; 2University of California at Berkeley,Dept. of Matls. Sci. and Mineral Eng., Berkeley, CA94720USA The novel spouted-bed electrode (SBE) is a cath-ode system where copper is deposited at a high cur-rent density in a moving bed of copper particles. Pre-liminary results on the deposition of copper fromacidic sulfate electrolytes using this novel cathodesystem were described during Copper’95 conference.Despite a high current density, the electrical energyconsumption was equal to or lower than that in theconventional electrowinning. The present paper de-scribes more investigations on SBE. The SBE consists ofcopper particles with approximately I nun diameteronto which copper is deposited from acidic sulfateelectrolyte whose composition is similar to conven-tional electrowinning. Three types of anodes wereused in conjunction with the spouted-bed cathode,namely, DSA anode for oxygen evolution, and twonovel anodes. One anode is less expensive than DSA;however it showed much promise in energy consump-tion. At a superficial current density of 2200 A/m2, theenergy consumption was around 1.0 kWh/kg cop-per. The research activities described in this paper weresupported by BHP Copper.

3:15 PMGuar Concentration Measurement with the CollaMatSystem: Peter Stantke1; 1Norddeutsche AffinerieAktiengesellschaft, Hovestrasse 50, Hamburg 20539Germany In recent years the CollaMat process has been usedsuccessfully worldwide in a number of copperelectrorefining tankhouses as an instrument for mea-suring the glue concentration and optimizing cath-ode quality. Owing to its measuring principles theCollaMat can be used not just for measuring the con-centration of active glue but also the activity of othersubstances, which have an impact similar to glue onthe copper deposition. In SX-EW plants guar is fre-quently used instead of glue as a leveling additive. Inour laboratory the effect (activity) and the decom-position rate of guar in copper electrolyte was exam-ined. As expected, the results show that guar has aneffect similar to glue on the copper deposition. How-ever, at the same temperature, a greater quantity ofguar is required to achieve the same results. As withglue, the decomposition rate (due to hydrolysis) ofguar is strongly dependent on the temperature. There-fore, in practice, its on-line monitoring is necessary toguarantee the same guar activity at any time.

3:40 PM Break

4:10 PMIron, Chloride and Permanganate Control in CopperElectrowinning Tankhouses: Richard Shaw1; Juan D.Illescas1; Cara Tomasek1; Simon Jupp1; David Dreisin-ger2; B. Wassink2; Dave Readett3; Tom Lancaster4;1Eichrom Industries, Inc., Hydrometallurgy, 8205 S. CassAve., Suite 111, Darien, IL 60561 USA; 2University of Brit-ish Columbia, Dept. of Metals and Matls. Eng., 309-6350 Stores Rd., Vancouver, British Columbia, CanadaV6T 1Z4; 3Straits Resources Limited, Level 3 Gold FieldsHouse, 1 Alfred St., Sydney, NSW 1220 Australia; 4NiftyCopper, WA Australia Iron, chloride and manganese are the three majorimpurities transferred to copper electrowinningtankhouses via chemical and/or physical entrainment.The control of these impurities via bleeding oftankhouse electrolyte is costly. Recently, Eichrom In-dustries have developed an improved iron controlprocess and tested this process in a pilot study at theGirilambone Copper Company (GCC). The patentedprocess utilizes a fixed bed ion exchange reactor filledwith Eichrom’s Diphonix resin. Iron is loaded on theresin and subsequently eluted by a cuprous sulfateeluant. The control of chloride and manganese hasbeen studied using different chemical techniques. Theremoval of chloride from electrowinning electrolyteswas tested using precipitation of chloride as cuprouschloride. Copper wire cuttings are used to producecuprous ions. Chloride levels are reduced to around30 ppm in electrolyte at 40ϒC. The removal of man-ganese using a precipitation process practiced in zincelectrowinning purification has been tested for imple-mentation. The process involves reacting manganousions in solution with permanganate ions. The reac-tion produces an insoluble manganese dioxide re-action product. The bench scale and pilot plant re-sults from testing of these purification processes arereported.

4:35 PMIron Removal from Leachate by Limestone Precipita-tion and Direct Electrowinning of Copper: BaoguoZhang1; Maurice C. Fuerstenau1; 1University of Ne-vada, Dept. of Chem. and Metall. Eng., MackeySchool of Mines, Reno, NV 89557 USA A study of iron-removal from copper leachate bylimestone precipitation followed by direct electrow-inning of copper has been conducted. The influenceof the process parameters: amount of precipitant,contact time, temperature, agitation intensity, solu-tion acidity, and initial iron concentration on iron-removal was investigated. The effects of electrowin-ning time, cell voltage, solution acidity and tempera-ture on electrowinning of copper were also investi-gated. The leachate contained 1.20 g/l Cu2+ and 7.41g/l total iron at pH 2.27. After contacting with 14 g/lprecipitant for 2 hours, 97.5% of the iron was attenu-ated and 98.4% of the copper was recovered. Withthe following electrowinning conditions: 3 lead an-odes, 3 stainless steel cathodes, 2.5 V, 39.41 A/m2 and10.7 g/l H2SO 4 copper recovery was 98.4%. Purity ofcopper powder produced was greater than 99.0%.

5:00 PMModeling and Simulation of Copper Electrowinning:Hossein Aminian1; Claude Bazin1; Daniel Hodouin1;

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1Laval University, Dept. of Mining and Metall., Ste-Foy,Québec, Canada G1K-7P4 Copper electrowinning (EW) is an important pro-cess in connection with the solvent extraction to pro-duce pure and marketable copper cathodes. A phe-nomenological model was developed to simulate thecopper electrowinning process. The simulator is usedto predict the operation of the Mines Gaspe pilotplant electrowinning cells put in operation in 1996.Results confirm the potential of the simulator thatwould subsequently be used for student training, pro-cess optimization and assessing the performances ofcontrol strategies.

5:25 PMApplication of a Two Phase Hydrodynamic Modelingto an Electrowinning Cell: Andreas Filzwieser1; KlausHein1; Peter Paschen1; G. Hanko1; Herwig Grogger2;1University of Leoben, Dept. of Nonferrous Metall.,Franz-Josef-Strasse 18, Leoben, Styria A-8700 Austria;2AVL List GmbH, Hans-List-Platz 1, Graz, Styria A-8020Austria The highest current density suitable for the electrow-inning process is between 50 to 60% of its limiting cur-rent density. One of the most important influences onthe limiting current density is the thickness of the hy-drodynamic boundary layer near the electrode sur-face. Therefore, the fluid flow in a copper electrow-inning cell is calculated. The numerical simulation—using the CFD-software package FIRE —considers allthree different types of the fluid flow, namely, thenatural convection, the forced convection by elec-trolyte circulation and the forced convection by elec-trochemically induced gas stirring. The simulation ofnatural convection is based on the different densityvalues in the boundary layer at the electrode surfacegiven by a density/concentration correlation. Thecopper concentration—linked with the current den-sity by Faraday law—is solved by an additional trans-port equation. The simulation of the forced convec-tion by the electrochemically-induced gas stirring isdone by using a real two-phase calculation. Thatmeans that all differential equations are solved againfor the second phase. The numerical solution of thefluid flow field is compared with the results of LDA-measurements which were done in a special cell. Thesoftware for the LDA enabled a calculation of thevoid fraction possible and therefore a rough estimateof the mass transfer coefficient through the prevail-ing gas bubble induced convection can be madeby assuming the influence of relative bubble volume.

5:50 PMA Statistical Approach Study of Copper Electrowin-ning Parameters: Damir Valic1; A. S. Tombalakian1;A. Alfantazi1; R. R. Moskalyk1; 1Laurentian University,School of Engr., 935 Ramsey Lake Rd., Sudbury,Ontario, Canada P3E 2C6 In 1997, 9.2 million tonnes of mined, recoverablecopper was produced, of which, 1.8 million tonnesor 19.4% was produced by leaching, solvent extrac-tion and electrowinning. The amount of copper pro-duced by this method grew faster than those attainedfrom concentrate smelting, signifying the growing im-portance of this low-cost production method. Statisti-cal experimental design, unlike traditional ap-proaches, allows for proper distribution of experimentswithin the boundaries of factors being studied such

that the number of experiments required to developa sound relationship between the factors and a re-sponse is minimized. In the past, very little use has beenmade of statistical experimental design in copperelectrowinning studies. Traditional one-variable-at-a-time approaches are widely employed for this pur-pose. The present study employs a factorial experi-mental design to relate current efficiency with cur-rent density (180 and 300 A/m2), copper concentra-tion (25 and 65 g/L), and temperature (40 and 60ϒC).Pure synthetic electrolyte with a constant acid con-centration of 180 g/L was used throughout the study.The designed study produced a linear relationshipwhere the independent variables of current density,copper concentration, and temperature, and theirinteractions, were found statistically significant. It wasshown that current efficiency could not solely be usedas a predictor of copper cathode quality. The qual-ity of the deposit is difficult to be incorporated into amodel or relation. It was determined that other mea-sures, such as cathode morphology and crystal struc-ture should be considered. This was done throughXRD and SEM analysis.

Pyrometallurgy-Operations: Session VII

Wednesday PM Room: EstrellaOctober 13, 1999 Location: Pointe Hilton Resort

Session Chair: Chris Newman, Kennecott UtahCopper Corporation, Magna, UT USA; R. Alvarado,El Teniente Division, CODELCO-Chile, Rancagu,Chile

2:00 PMOnline SO2 Analysis of Copper Converter Off-Gas: A.A. Shook1; O. Pasca1; G. A. Eltringham1; 1BHP Cop-per Smelting and Refining, 200 South Redington Rd.,P.O. Box M, San Manuel, AZ 85631 USA The off gas from the #5 converter at BHP Copper’sSan Manuel smelter was analyzed continuously overa period of several weeks using an on-line SO2 ana-lyzer. These data has shown that the oxygen utiliza-tion efficiency of this copper converter was somewhatlower than anticipated, and that oxygen efficiencydeclines significantly during the copper blow. A sharpreduction in SO2 generation was consistently observedat the end of the copper blow, which could be usedby converter operators to prevent over-blowing andminimize rolling out of stack.

2:25 PMArsenic Slagging of High Matte Grade Converting ByLimestone Flux: C. M. Acuña1; J. Zuñiga1; C. Guibout1;P. Ruz2; 1Subgerencia Fundición de Concentrados,Codelco Chile-Division Chuquicamata, Chuqui-camata, Chile; 2Institute for Mining and MetallurgyInnovation/IM2, Av. del Parque 4980, CiudadEmpresarial, Huechuraba, Santiago, Chile At the Chuquicamata Division of Codelco-Chilehigh arsenic concentrates are produced, which atthe smelter are processed via the Outokumpu FlashFurnace and Teniente Converters to obtain copper

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mattes. In the case of the Teniente Converters the pro-duction of matte grade near white metal composi-tion is a common practice since the eighties and pro-vided in pyrometallurgical route no appropriate mea-sures are taken, penalties have to be paid becauseof arsenic content in the anodes. During smelting hugevolume of slag is produced and elimination of ar-senic by slagging at this step is not economically at-tractive. Although during fire refining is possible toeliminate arsenic by use of mixtures of calcium andsodium carbonates this alternative is expensive, takeslong process time and decreases the lifetime of therefractory lining. In spite of these facts a reasonablyway to control arsenic in metal, and therefore in theanode, is taking action in the converting step. Theeffects of oxygen and arsenic content in metal, ar-senic in white metal and basicity index of the slagupon the distribution coefficient of arsenic betweenmetal and slag were investigated at pilot and indus-trial levels. The best results are obtained for metalsaround 7,000 ppm oxygen and 0.3 basicity index slag,which results in a 5.7 distribution coefficient for a 5,800-7,100 ppm arsenic content in white metal, 18%-24%CaO slag at 1473-1523K. Furthermore, no significant/visible refractory wear has been realized.

2:50 PMUse of Optical On-line Production Control in CopperSmelters: Willy Persson1; Wilhelm Wendt1; S. DemetrioJ.2; 1Semtech Metallurgy AB, Ideon, Lund S-223 70 Swe-den; 2ConOpti S.A., Cerro San Ramon 1491, LasCondes, Santiago, Chile The first installation at a copper smelter of aSemtech OPC System for continuous, on-line produc-tion control of copper converting in PS converters tookplace in 1994. At present OPC systems are installed at19 PS converters. The technology presents to the op-erator real-time information on the progress of theprocess he is controlling in the form of optical pro-cess parameters, thus facilitating dynamic processcontrol. The optical process parameters are basedon time and wavelength resolved registrations of thelight emitted by the off-gas flames and identificationof correlation between these parameters and char-acteristic metallurgical process data. The presentpaper provides a description of the technology asseen by the furnace operators and a summary ofoperating experiences made during five years of full-scale operation at various smelters, reviews influencesfrom the technology on smelter operational practisesand comments on recent developments as regardsnew applications of the technology.

3:15 PMPorous Plugs in Molten Copper Production and Refin-ing: A. J. Rigby1; Michael D. Lanyi2; 1Narco Canada,Inc., Non-Ferrous Mktg., P.O. Box 910, 4355 FairviewSt., Burlington, Ontario, Canada L7R 3Y7; 2Air Prod-ucts and Chemicals, Inc., Applications Dev., MetalsIndustries Grp., Allentown, PA 18195-1501 USA Current practices employing porous plugs to in-ject nitrogen into molten copper during primary smelt-ing are described. Nitrogen stirring increases heattransfer to the bath, eliminates temperature stratifica-tions, and improves efficiency during the steps ofdesulfurization and deoxidation. The opportunity touse porous plugs as the means to introduce reducinggases to deoxidize copper is also discussed. Previ-

ously reported laboratory results using porous plugs,which point to very high utilization efficiencies of hy-drogen when used as the reducing gas, are againreviewed. Advances in the design of the porous plug,and the introduction of a system enabling externalreplacement of plugs is also discussed.

3:40 PM Break

4:10 PMRedesigning the Flash Furnace Feed System at BHPCopper: D. J. Goodwill1; D. M. Jones2; T. A. Royal3;1H. G. Engineering Limited, 400 Carlingview Dr.,Toronto, Ontario, Canada M9W 5X9; 2BHP Copper,Inc., 200 S. Redington Rd., P.O. Box M, San Manuel,AZ 85631 USA; 3Jenike & Johanson, Inc., One Tech-nology Park Dr., Westford, MA 01886 USA BHP Copper operates a 3,400 tpd dry concentrate,single burner, Outokumpu flash smelting furnace (FSF)at their San Manuel copper smelter in Arizona. Thevery fine (-325 mesh), dry concentrate is fed to theburner from a 550 metric ton (nominal) capacity fur-nace feed bin via two drag chain feeders. Duringthe 10-year history of the furnace, operations havebeen plagued by serious feed flooding problems. Thefine concentrate sometimes becomes aerated dur-ing discharge from the bin and flows like a fluid atvery high, uncontrollable rates to the burner. This re-sults in upset conditions at the concentrate burnerresulting to poor furnace metallurgy. This paper willexamine the problems of uncontrolled feed from thefurnace bin (i.e. flooding), and instantaneously feed-ing a flash smelting burner. It will show that a dragchain is a poor choice of feeder when high rates areneeded, and that drag chains always produce a fun-nel flow pattern in a bin. BHP’s drag chains causenarrow diameter, high velocity flow channels withinthe stored material. Consequently, there is insufficientresidence time for the concentrate to fully de-aeratebefore discharge, hence flooding occurs. In additionto the flooding problem, drag chains create a pul-sating flow to the concentrate burner due to the ten-dency for material to slough off in discrete chunks atthe discharge end of the slow moving chain conveyor.During the scheduled FSF rebuild in May 1999, BHPintends to remove the drag chains, modify the bin toa mass flow design and to use STAMET® multi-discfeeders to accurately and instantaneously control therate of discharge from the bins. Air slides will be usedto convey the concentrate to the burner.

4:35 PMDevelopment of More Environment-Friendly and Cost-Effective Drying Facility for Copper Concentrates:Jarkko Kalevi Partinen1; Shao Long Chen1; Olli Tiitu1;1Kumera Corporation, Tech. Ctr., Kumerankatu 2,Riihimäki, Finland FIN-11100 Europe Drying is a unit process which has numerous appli-cations in the metallurgical process industry. KumeraTechnology Center, being a worldwide equipmentand process supplier, has developed sophisticatedsolutions for both direct and indirect drying. In con-ventional direct drum drying, the energy is taken fromcombustion of fossil fuels, requiring energy input andemitting considerable amount of off gases. In mod-ern copper smelters, thermal energy from the off gasesis recovered in waste heat boilers making the steamavailable. Using that steam as the energy source for

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concentrate drying, the total volume of off gases canbe considerably reduced and releasing of harmfulcombustion gases into the atmosphere can beavoided. Kumera Technology Center has recentlydeveloped and promotes a new steam drying pro-cess for drying of copper concentrates. In the devel-opment of the new dryer, Kumera’s approach hasbeen to combine the best properties of both the steamdryers and the drum dryers. In the design special at-tention has been paid to overcome problems of ex-cessive wear and clogging and to reduce the re-quired maintenance operations. In this paper theenvironmental issues and energy consumption relatedto both direct and indirect drying processes are dis-cussed. The estimated operation costs and emissionlevels are compared, based on calculations and thedata collected from industry. Finally, the developmentproject of the Kumera Steam Dryer is briefly reviewed.

5:00 PMIndirect Drying of Concentrates at Copper and NickelSmelters by Means of Innovative, Cost Effective Envi-ronmental Technologies: Christian Monjau Sagedahl1;Hans Joergen Broenlund1; 1Kvaerner Eureka, Proc.Div., Joseph Kellers vei 20, P.O. Box 38, Tranby, Lier N-3401 Norway The stringent environmental regulations for air pol-lution regarding emission control, along with the needof dry concentrates to feed autogenous smelting pro-cesses, are enhancing the development of cleanertechnologies. Indirect drying of concentrates by aKvaerner steam dryer is a technology with promisingresults, reducing dust entrainment to the exhaust gasstream and leading to smaller dust separation units.The Kvaerner dryers are designed for a very high avail-ability, a high-energy efficiency, low amount andvelocity of exhaust gases, no SO2, CO or CO2 emis-sions combined with a wide range of satisfactory op-erating conditions and low total operational costs.

5:25 PMAgglomeration of ESP Dusts for Recycling to PlantSmelting Furnaces: Peter Ryan1; Neil Smith1; ClaudioCorsi1; Tim Whiteus1; 1Produ-Kake®, Inc., 3285 Main-way, Unit 4, Burlington, Ontario, Canada L7M 1A6 A patented process for agglomeration of SmelterESP dusts is described. Addition of suitable bindersfollowed by compaction, transforms fine, difficult tohandle material into a dry, flowable agglomeratesuitable for plant reentry. Details for the agglomera-tion process metallurgy and laboratory pilot planttesting are discussed. An example of full scale plantoperations is described.

5:50 PMPhilippines Associated Smelting Electrostatic PrecipitorUpgrade: Clodualdo C. Conde1; Bob Taylor2; SureshSarma3; Jose Suarez2; 1PASAR, 3rd and 4th FloorsMorning Star Ctr., 347 San Gil J. Puyat Ave., Makati,Metro Manila 3120 Philippines; 2BHA Group, Inc., 8800E. 63rd St., Missouri, Mo 64133 USA; 3BHA Group Inter-national Private Ltd., Friend’s Park Co-op Society, 2ndFloor, Lohia & Jain Business Ctr., Senapati Bapat Marg,Shivajinagar, Pune 411 053 India In order for Philippines Associated Smelting andRefining Corporation (PASAR) to remain a leader inthe copper smelting and refining industry, continu-ous improvements in plant technology are required.

Reliable performance of plant equipment is essentialfor a competitive smelting operation. PASAR is con-stantly searching for the best equipment and tech-nology to allow us to manufacture products moreefficiently. When the Smelter was commissioned in1993, the Flash Furnace off-gas treatment system wasa constant source of problems. There were frequentshut-downs of the electrostatic precipitator due tomaterial buildups on the discharge electrodes andcollecting plates. In 1998, the precipitator was suc-cessfully upgraded to eliminate the buildup problemsand to increase the collection efficiency. The upgradegreatly reduced down time and maintenance, andthe enhanced collection efficiency also eliminatedpluggage problems and material losses in the AcidPlant. This extensive precipitator upgrade was accom-plished during a 30-day Smelter turnaround.

Smelting: Technology Development,Process Modeling and Fundamentals:Fundamental Studies and TechnologyDevelopment - II

Wednesday PM Room: GoldwaterOctober 13, 1999 Location: Pointe Hilton Resort

Session Chairs: Torstein Utigard, University ofToronto, Dept. of Metall. and Mats. Sci., 184 Col-lege St., Toronto, Ontario, Canada M5S 3E4; RalphHarris, McGill University, Dept. of Mining and Metall.Eng., Rm. 2220 Wong Bldg., 3610 University St.,Montreal, Québec, Canada H3A 2B2

2:00 PMStudies on the Reactivity of Copper and Nickel Mattesunder Suspension Smelting Conditions: Johanna TiinaSjöblom1; H. Yliheljo1; Ari Jokilaakso1; Jukka Yli-Penttilä2; 1Helsinki University of Technology, Dept. ofMats. Sci. and Rock Eng., P.O. Box 6200, Espoo, HUTFIN-02015 Finland; 2Huber Testing Oy, P.O. Box 120,Vantaa FIN-01511 Finland New copper and nickel processes, flash convert-ing and DON, direct high-grade nickel matte smelt-ing, have been developed in order to replace theconventional and not so environmentally friendly PS-converting process. With a laboratory scale laminar-flow furnace the combustion reactions of sulfidic feedparticles can be investigated under simulated flashsmelting conditions. In the present study, finely groundand screened feed fractions of a copper matte anda nickel matte were flash oxidized in a laminar-flowfurnace. The experiments were carried out using 20,21 vol% and 75 vol% 02 in nitrogen, at temperatures1100 and 1300ϒC and reaction zone length of 7.5-16cm. The samples were quenched in a water film aftera specified reaction time. The matte particle reac-tions were stopped after short residence time inter-vals in order to obtain a better understanding of thereaction mechanisms. Chemical analysis was usedto determine oxidation degree, and optical andscanning electron microscope combined with energydispersive analysis was used for characterization of

57

the reacted particles. On the basis of the experimen-tal results the reactivity of the mattes is discussed andpossible reaction and dust formation mechanisms areconsidered.

2:25 PMBehaviour of Copper Matte Particles in Suspension Oxi-dation: Esa J. Peuraniemi1; Juha Jarvi2; Ari Jokilaakso1;1Helsinki University of Technology, Lab. of Mats. Proc.and Powder Metall., P.O. Box 6200, Espoo, HUT FIN-02015 Finland; 2Outokumpu Research Oy, P.O. Box 60,Pori FIN-28101 Finland Recently commissioned Kennecott-Outokumpuflash converting was developed to replace the ap-proved but environmentally outdated Peirce-Smith,converting to satisfy the globally tightening emissionregulations. In the present study, dust formation andreaction mechanisms of two copper mattes with dif-ferent experimental parameters were studied in leansuspension conditions. Both mattes had very highcopper content of approximately 75 wt% and lowiron content of 4.5 wt% and 1.2 wt% Fe. A laboratoryscale, vertical laminar-flow furnace with a low feed-ing rate was used to simulate the phenomena takingplace in the reaction shaft of a flash converter. Ex-perimental conditions included temperature of1300ϒC with reaction gas oxygen contents of 20 vol%,50 vol%, and 75 vol%. In the experiments, sieved par-ticle fractions were fed to the furnace and sampledafter short reaction time intervals by quenching theminto a water film. Collected particles were analysedchemically for their main elements to define their re-moval rates. Also, optical and scanning electron mi-croscopy with EDS-analyser were applied to deter-mine phenomena occurring during reactions. Kinet-ics of oxidation as well as ignition of particles are dis-cussed. Changes in particle morphology, size, andcomposition are reviewed to describe dust formationand reaction mechanisms.

2:50 PMSampling the Shaft of the Olympic Dam Copper FlashFurnace: D. N. Collins1; F. R. A. Jorgensen2; W. J.Rankin2; 1WMC Resources, Ltd., (Olympic Dam Cor-poration); 2CSIRO Minerals, G.K. Williams Coopera-tive Rsch. Ctr. for Extractive Metallu., P.O. Box 312,Clayton South Victoria 3169 Australia A sampling program was conducted in which bothspoon and isokinetic sampling techniques were usedto collect samples from the reaction shaft. The sampleswere then characterised by chemical, XRD and min-eralogical analysis. Further information was acquiredby measuring the oxygen potential and temperatureat the bottom of the shaft using disposable probes.Comparison of the results of the two sampling meth-ods showed that the spoon samples were devoid ofmaterial less than 25m. Sulfur analyses on the samplesprovided information on the extent of reaction, plumeshape and recirculation patterns. Disposable probemeasurements showed the measurable particle tem-peratures ranged from 1150 to 1700ϒC and that thematerial falling into the bath had a normalised oxy-gen potential similar to the slag. These latter mea-surements combined with the sulphur elimination andmineralogical analyses provided further informationon the extent of reaction and enabled the reactionsequence to be ascertained.

3:15 PMOxidation of Copper Matte by Gas Injection: RonHiram Schonewille1; James M. Toguri2; 1FalconbridgeLimited, Falconbridge Tech. Ctr., Falconbridge,Ontario, Canada P0M 1S0; 2University of Toronto, Dept.of Metall. and Mats. Sci., 184 College St. W., Toronto,Ontario, Canada M5S 1A4 Experiments were conducted by injecting air-oxy-gen gas mixtures through a ceramic lance into mol-ten copper matte and measuring the sulphur dioxidecontent of the offgas. The injection conditions werecharacterized by measuring pressure fluctuations im-mediately upstream of the lance and capturing theinformation on an oscilloscope screen. The param-eters investigated were gas flowrate, lance geometry,lance immersion, orifice diameter and melt composi-tion. An overhead nitrogen lance was used in spe-cific tests to create an inert gas blanket directly abovethe bath surface to inhibit reaction in this region. Theextent of oxidation was modeled by separating thegas-liquid contact into three stages; bubble growth,bubble rise and bubble rupture. The contribution ofeach stage to oxygen utilization was determined byvarying the lance immersion and by performing testsboth with and without an inert gas blanket. Bubblerise was found to be relatively unimportant, account-ing for less than 5% of the total oxygen utilization.Bubble rupture and bubble growth were found tocontribute approximately equally, with bubble rup-ture becoming more important with increasing gasflow rate. This study highlights the importance of re-actions taking place above the bath surface in acopper converter.

3:40 PM Break

4:10 PMActivity Measurement of Minor Elements in Cu-S-Me(Me = Ag, Se, Te) and Cu-Fe-S-Me Matte Systems at1473 K by Mass Spectrometric Method: Alireza Zakeri1;Mitsuhisa Hino1; Kimio Itagaki1; 1Tohoku University,Instit. for Adv. Mats. Proc. (IAMP), 2-1-1 Katahira,Aoba-ku, Sendai, Miyagi-ken 980-8577 Japan To evaluate the behavior of minor elements in thecopper smelting process, activities of silver, seleniumand tellurium at minor concentration were determinedat 1473 K within the miscibility gap of the Cu-S-Me(Me = Ag, Se, Te) and Cu-Fe-S-Me systems varied inFe/Cu ratio. Phase relations between the immisciblemetal and matte phases in the foregoing systems werefirst established by a quenching technique at 1473 Kto supplement the activity measurement data. AKnudsen-effusion mass spectrometer, capable of han-dling complex gaseous systems and relatively smallvapor pressures, was adopted for activity determina-tion. Using a multiple Knudsen-cell, the ion intensityof minor element in the sample under study was mea-sured simultaneously with that in a reference sample.Activity was obtained from the ratio between themeasured ion intensities as well as the known activityvalue of the minor element in the reference sample.Limiting activity coefficients of the minor elementswere correlated with composition of the matte. Basedon the experimental results, the vaporization behav-ior of the minor elements has been discussed.

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4:35 PMDirect Reduction of Copper-Iron-Silicon Oxide Melts:Roberto Andrés Parra1; Igor Wilkomirsky1; Michel PaulAllibert2; 1Universidad de Concepción, Dept. Ing.Metalúrgica, Edmundo Larenas 270, Concepción,Chile; 2Institute National Polytechnique de Grenoble,LTPCM, BP. 75, Saint Martin D’Heres 38402 France The selective reduction smelting of Cu2O in Cu2O-FeOx-SiO2 melts has been studied at the laboratorylevel, using as a feed a dead roasted calcine from acopper concentrate. The purpose of the study wasto evaluate the kinetic and mechanisms of the indi-rect reduction with CO and the direct reduction withgraphite from 1260ϒC to 1350ϒC. The reduction rateby CO was found to be 10-2 to 10-1 mole Cu2O m-2s-1.The graphite reduction macrokinetics for FeO andFe2O3 containing melts, was found to be a first orderreaction with respect to the Cu2O concentration, witha kinetic constant of 10-4 to 10-3s-1. The reduction ratewas not sensitive to temperature nor to stirring, in therange studied. The measured reduction rate is almostone order of magnitude larger than the observed ratefor the direct reduction of FeO.

5:05 PMCorrosion Testing of Chrome-Free Refractories for Cop-per Production Furnaces: Michael D. Crites1; Mark E.Schlesinger1; 1University of Missouri-Rolla, Dept. ofMetall. Eng., 1870 Miner Circle, Rolla, MO 65409-0340USA As part of a multi-year program for assessing theviability of chrome-free refractories in copper smelt-ing, converting and refining furnaces, dynamic cor-rosion tests have been conducted on a series of re-fractories from the magnesia-alumina system, usinga ferrous silicate slag. The corrosion rates of the testrefractories are compared with those of a referencemag-chrome brick, and recommendations are madefor more in-depth evaluations of the more corrosion-resistant materials.