Recent Developments in Copper Hydrometallurgy

Transcription

1 Recent Developments in Copper Hydrometallurgy John O. Marsden Senior Vice President, Technology & Product Development Sohn International Symposium on Advanced Processing of Metals and Materials: Principles, Technologies and Industrial Practice; August 27-31, 2006 San Diego, CA, USA Phelps Dodge Corporation

2 Outline Safety Historical context Solution extraction and electrowinning Atmospheric leaching Secondary sulfides Primary sulfides Pressure leaching Other developments affecting copper hydrometallurgy Phelps Dodge Corporation

3 Safety Phelps Dodge philosophy Zero & Beyond Phelps Dodge Corporation

4 Hydrometallurgy in Copper Extraction Phelps Dodge Corporation

5 Phelps Dodge Long Track Record of Technology Deployment Copper Produced (millions of pounds) 3,000 2,500 2,000 1,500 1, Tyrone SX/EW Morenci SX/EW Chino SX/EW Morenci Northwest Extension Candelaria 1 Large scale SX/EW Computerized haul truck dispatch GPS ore control Leach recovery optimization Concentrate grade enhancement Morenci Southside Morenci MFL, El Abra ROM Cyprus Acquisition Candelaria 2 Curtailment Commenced Chino 1/3 Acquisition Expert control systems Concentrator adaptive control Mine for leach Haul truck tire technology Concentrate leach (2003) Year Phelps Dodge Corporation

6 Solution Extraction and Electrowinning Stockpile Leaching (Oxide) (Chalcocite) Mine Primary Crushing Sec/Tert Crushing Heap Leaching (Oxide) (Chalcocite) Solution Extraction Electro- Winning Acid Customers Milling (Chalcocite) (Chalcopyrite) Flotation Smelting Electro- Refining Technology development efforts under way to reduce energy consumption in electrowinning by 15-35% Technology not yet proven, but showing promise Phelps Dodge Corporation

7 Solution Extraction and Electrowinning at Bagdad, Arizona Phelps Dodge Corporation

8 Solution Extraction & Electrowinning Rancher s Bluebird mine, Arizona Bagdad, Arizona ZCCM, Zambia Miami, Arizona Inspiration, Arizona Cananea, Mexico Pinto Valley, Arizona Tyrone, New Mexico Ray, Arizona Morenci, Arizona Sierrita, Arizona Chuquicamata, Chile Chino, New Mexico Phelps Dodge Corporation

9 Example of Technology Transforming Copper Production (PDC share; millions of pounds) 2,500 2, % conventional % SX/EW 1,500 1, Conventional SX/EW Phelps Dodge Corporation

10 Morenci Modoc SX Plant Phelps Dodge Corporation

11 Koch Solution Extraction In-Pipe Reactor Phelps Dodge Corporation

12 Enhanced Sulfide Heap and Stockpile Leaching Phelps Dodge Corporation

13 Biologically Enhanced Leaching leach solution air air Phelps Dodge Corporation

14 Cerro Verde Leach Pad 4 - Grasshopper Stacker Phelps Dodge Corporation

15 Morenci Mine-for-Leach Agglomeration Drums Phelps Dodge Corporation

16 Morenci Mine-for-Leach North Stacker Phelps Dodge Corporation

17 Leaching Developments Bacterial Augmentation Stream contains 3x10 8 cells/ml genetically selected bacteria Delivers two separate bacterial strains simultaneously Skid mounted Design based on Bagdad plant shown below Phelps Dodge Corporation

18 Advanced Modeling to Improve Heap Performance Air and solution modeling in heap Temperature profile in heap Phelps Dodge Corporation

19 Enhanced Chalcopyrite Leaching Bagdad Crystal Mountain Phelps Dodge Corporation

20 Morenci Enhanced Stockpile Leaching Low-grade ore from Western Copper deposit Below mill cut off grade material Mixed sulfide minerals chalcopyrite, chalcocite 188 million ton stockpile to be constructed Air injection Bacteria augmentation Controlled solution application Largest engineered chalcopyrite stockpile leach in the world Phelps Dodge Corporation

21 Concentrate Leaching Alternative to Smelting & Refining Phelps Dodge Corporation

22 Copper Extraction in 1980s and 1990s Primary sulfide ores Mine Secondary sulfide and oxide ores Flotation Leaching Smelting SX Refining EW Rod Mill or Customer Phelps Dodge Corporation

23 Concentrate Leach Technology Replaces Smelting/Refining Primary sulfide ores Mine Secondary sulfide and oxide ores Flotation Smelting Concentrate Leaching Leaching SX Refining EW Rod Mill or Customer Phelps Dodge Corporation

24 Copper Concentrate Leaching History Process developments s and 80 s Ammonia - Arbiter Chloride - CLEAR, SOX, Cuprex Sulfate - Roast/Leach/Electrowin (Lakeshore) Many others Phelps Dodge Corporation

25 Copper Concentrate Leaching History Process developments s and 80 s Ammonia - Arbiter Chloride - CLEAR, SOX Sulfate - Roast/Leach/Electrowin (Lakeshore) Many others Reasons for lack of commercial success High cost (capital & operating) Problems with materials of construction Problems with operability/maintainability Process complexity Precious metals recovery problems Problems with copper cathode quality Primitive, early stage SX/EW technology Not integrated with leaching operations Significant advances in smelting technology Phelps Dodge Corporation

26 Copper Concentrate Leaching More Recent Developments Ammonia - Escondida Sulfate Phelps Dodge Placer Dome CESL/Teck Cominco (chloride-assisted) UBC/Anglo American Activox Dynatec Biological BHP-Billiton BioCop Bactech-Mintek Others Chloride/Bromide Process Intec Chloride Outokumpu HydroCopper Nitrate Other Phelps Dodge Corporation

27 Phelps Dodge Concentrate Leaching Milestones 2Q 1998 Sulfate-based concentrate leaching development started Batch testwork at Hazen Research, Dawson and Phelps Dodge Process Technology Center Q 2001 Nov 2001 Mar 2003 July 2003 Continuous Pilot Plant Testing Technology Development Agreement executed with Placer Dome Bagdad HT Project approved Start-up: First concentrate feed All design parameters met, steady state operation Four years from first testing to commercial demonstration Phelps Dodge Corporation

28 Bagdad Concentrate Leach Plant Schematic Concentrate Slurry Slurry Storage Tank PLV Feed Tank PLV Flash Vessel PLS to SX/EW and Cathode Production Tails PLS Pond and SX/EW Neut #4 Neut #3 Neut #2 Neut #1 Strong PLS Tank CCD #2 CCD #3 CCD #4 CCD #1 S C R U B B E R #2 S C R U B B E R # Phelps Dodge Corporation

29 Bagdad Concentrate Leach Plant August, Phelps Dodge Corporation

30 Pressure Leaching Vessel at Bagdad Phelps Dodge Corporation

31 Solid-liquid Separation at Bagdad August, Phelps Dodge Corporation

32 Bagdad Concentrate Leach Plant Copper Production 4,000,000 3,500,000 3,000,000 2,500,000 2,000,000 1,500,000 Production (lbs) 1,000, ,000 Mar-03 Apr-03 May-03 0 Jun-03 Jul-03 Aug-03 Sep-03 Oct-03 Nov-03 Dec-03 Jan-04 Feb-04 Mar-04 Apr-04 May-04 Jun-04 Jul-04 Aug-04 Sep-04 Oct-04 Nov-04 Dec-04 Production (lbs) Design Basis Production Phelps Dodge Corporation

33 Phelps Dodge Concentrate Leaching Milestones (continued) May 2004 May 2005 Dec Q 2007 Conversion of Bagdad demonstration plant to medium temperature process started Start-up: medium temperature and direct electrowinning (MT-DEW) process Completion of MT-DEW process demonstration Scheduled completion of Morenci facility Phelps Dodge Corporation

34 Bagdad MT-DEW Process Conversion Super-fine Grinding Phelps Dodge Corporation

35 Direct Copper Electrowinning at Bagdad, AZ Phelps Dodge Corporation

36 Morenci Concentrate Leaching Application Provides economically viable alternative to smelting and refining Generates by-product acid for leaching Eliminates freight cost for concentrate shipments and acid deliveries Decouples Morenci from smelter balance dependency Reduces Morenci s mill conversion costs Morenci Western Copper concentrate mineralogy Mixed chalcopyrite, covellite, chalcocite, pyrite Medium temperature and direct electrowinning ( MT-DEW ) process selected Best fit with Morenci concentrate production and acid balance Utilize existing EW and SX capacity at Morenci Copper production capacity = 75,000 tons per year Copper recovery slightly higher than smelting and refining Phelps Dodge Corporation

37 Production Decisions Impacted by Concentrate/Acid Balance External concentrate source North American Concentrate Bagdad Sierrita Chino (partial capacity) Cobre Morenci (off line) Candelaria concentrate Chino Smelter 650,000 tpy capacity (off line) Miami Smelter 750,000 tpy capacity (operating) External acid source North American Leach Morenci Bagdad Sierrita Chino Tyrone (partial capacity) Miami (partial capacity) External acid consumer Phelps Dodge Corporation

38 Morenci Concentrate Leaching Facility 3D Model View Phelps Dodge Corporation

39 Other Developments Affecting Copper Hydrometallurgy Material Characterization Comminution Alternative Products Phelps Dodge Corporation

40 High-Pressure Grinding Rolls Cerro Verde milling circuit to include high pressure grinding rolls (HPGR) instead of SAG mills Pros Higher throughput Greater energy efficiency Greater flexibility Lower unit cost Cons Additional capital cost Financial Impact Significantly reduces power consumption and unit production costs Note - Use yellow to highlight font colors (but never titles) Phelps Dodge Corporation

41 Material Characterization QemSCAN Technology Phelps Dodge Corporation

42 New Copper Products Copper powder technology Potential replacement for cathode to rod Specialty copper powders Copper powder process reduces or eliminates the following: Manual harvesting of cathodes Cell cleaning Stainless blank repairs and replacement Stripping machines Slippery or brittle cathodes Focused on reducing costs and improving process safety and efficiency PDC proprietary technology Demonstration plant in operation at Morenci, AZ Phelps Dodge Corporation

43 Thank You Sohn International Symposium on Advanced Processing of Metals and Materials: Principles, Technologies and Industrial Practice; August 27-31, 2006 San Diego, CA, USA Phelps Dodge Corporation