1 2006 Phelps Dodge Corporation

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

Recent Developments in Copper Hydrometallurgy

John O. MarsdenSenior Vice President, Technology & Product Development

2 2006 Phelps Dodge Corporation

Outline

Safety Historical context Solution extraction and electrowinning Atmospheric leachingySecondary sulfidesyPrimary sulfides

Pressure leaching Other developments affecting copper hydrometallurgy

3 2006 Phelps Dodge Corporation

Safety

Phelps Dodge philosophy Zero & Beyond

4 2006 Phelps Dodge Corporation

Hydrometallurgy in Copper Extraction

5 2006 Phelps Dodge Corporation

Phelps Dodge Long Track Record of Technology Deployment

0

500

1,000

1,500

2,000

2,500

3,000

83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03Year

C

o

p

p

e

r

P

r

o

d

u

c

e

d

(

m

i

l

l

i

o

n

s

o

f

p

o

u

n

d

s

)

Large scale SX/EW Computerized haul truck dispatch GPS ore control Leach recovery optimization Concentrate grade enhancement

TyroneSX/EW

MorenciSX/EW

ChinoSX/EW Morenci

NorthwestExtension

Candelaria 1

MorenciSouthside

Candelaria 2

Expert control systems Concentrator adaptive control Mine for leach Haul truck tire technology Concentrate leach (2003)

Morenci MFL,El Abra ROM

CyprusAcquisition

CurtailmentCommenced

Chino 1/3 Acquisition

6 2006 Phelps Dodge Corporation

Solution Extraction and Electrowinning

MineHeap

Leaching(Oxide)

(Chalcocite)

SolutionExtraction

Milling(Chalcocite)

(Chalcopyrite)Smelting Electro-Refining

Electro-Winning

Acid

Flotation

PrimaryCrushing

StockpileLeaching

(Oxide)(Chalcocite)

Sec/TertCrushing

Customers

Technology development efforts under way to reduce energy consumption

in electrowinning by 15-35%

Technology not yet proven, but showing promise

7 2006 Phelps Dodge Corporation

Solution Extraction and Electrowinning at Bagdad, Arizona

8 2006 Phelps Dodge Corporation

Solution Extraction & Electrowinning

1968 Ranchers Bluebird mine, Arizona1971 Bagdad, Arizona1974 ZCCM, Zambia1976 Miami, Arizona1979 Inspiration, Arizona1980 Cananea, Mexico1981 Pinto Valley, Arizona1984 Tyrone, New Mexico1985 Ray, Arizona1987 Morenci, Arizona1987 Sierrita, Arizona1987 Chuquicamata, Chile1988 Chino, New Mexico

9 2006 Phelps Dodge Corporation

Example of Technology Transforming Copper Production

0

500

1,000

1,500

2,000

2,500

85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04

Conventional SX/EW

(PDC share; millions of pounds)

1983 100% conventional2004 66% SX/EW

10 2006 Phelps Dodge Corporation

Morenci Modoc SX Plant

11 2006 Phelps Dodge Corporation

Koch Solution Extraction In-Pipe Reactor

12 2006 Phelps Dodge Corporation

Enhanced Sulfide Heap and Stockpile Leaching

13 2006 Phelps Dodge Corporation

Biologically Enhanced Leaching

air air

leach solution

14 2006 Phelps Dodge Corporation

Cerro Verde Leach Pad 4 - Grasshopper Stacker

15 2006 Phelps Dodge Corporation

Morenci Mine-for-Leach Agglomeration Drums

16 2006 Phelps Dodge Corporation

Morenci Mine-for-Leach North Stacker

17 2006 Phelps Dodge Corporation

Leaching Developments Bacterial Augmentation

Stream contains 3x108 cells/ml genetically selected bacteria Delivers two separate bacterial strains simultaneously Skid mounted Design based on Bagdad plant shown below

18 2006 Phelps Dodge Corporation

Advanced Modeling to Improve Heap Performance

Air and solution modeling in heap

Temperature profile in heap

19 2006 Phelps Dodge Corporation

Enhanced Chalcopyrite Leaching Bagdad Crystal Mountain

20 2006 Phelps Dodge Corporation

Morenci Enhanced Stockpile Leaching

Low-grade ore from Western Copper deposityBelow mill cut off grade materialyMixed sulfide minerals chalcopyrite, chalcocitey188 million ton stockpile to be constructedyAir injectionyBacteria augmentationyControlled solution application

Largest engineered chalcopyrite stockpile leach in the world

21 2006 Phelps Dodge Corporation

Concentrate Leaching Alternative to Smelting & Refining

22 2006 Phelps Dodge Corporation

Copper Extraction in 1980s and 1990s

Secondary sulfide and oxide ores

Primary sulfide ores Mine

LeachingFlotation

Refining

Smelting

Rod Mill or Customer

SX

EW

23 2006 Phelps Dodge Corporation

Concentrate Leach Technology Replaces Smelting/Refining

Secondary sulfide and oxide ores

Primary sulfide ores Mine

LeachingFlotation

Refining

Smelting

Rod Mill or Customer

SX

EW

ConcentrateLeaching

24 2006 Phelps Dodge Corporation

Copper Concentrate Leaching History

Process developments - 1970s and 80syAmmonia - ArbiteryChloride - CLEAR, SOX, CuprexySulfate - Roast/Leach/Electrowin (Lakeshore)yMany others

25 2006 Phelps Dodge Corporation

Copper Concentrate Leaching History

Process developments - 1970s and 80syAmmonia - ArbiteryChloride - CLEAR, SOXySulfate - Roast/Leach/Electrowin (Lakeshore)yMany others

Reasons for lack of commercial successyHigh cost (capital & operating)yProblems with materials of constructionyProblems with operability/maintainabilityyProcess complexityyPrecious metals recovery problemsyProblems with copper cathode quality yPrimitive, early stage SX/EW technologyyNot integrated with leaching operationsySignificant advances in smelting technology

26 2006 Phelps Dodge Corporation

Copper Concentrate Leaching More Recent Developments

Ammonia - Escondida Sulfate yPhelps DodgeyPlacer DomeyCESL/Teck Cominco (chloride-assisted)yUBC/Anglo AmericanyActivoxyDynatec

BiologicalyBHP-Billiton BioCopyBactech-MintekyOthers

Chloride/Bromide Process Intec Chloride Outokumpu HydroCopper Nitrate Other

27 2006 Phelps Dodge Corporation

Phelps Dodge Concentrate Leaching Milestones

2Q 1998 Sulfate-based concentrate leaching development started

1999-2000 Batch testwork at Hazen Research, Dawson and Phelps Dodge Process Technology Center

2000-2001 Continuous Pilot Plant Testing 3Q 2001 Technology Development Agreement

executed with Placer Dome Nov 2001 Bagdad HT Project approved Mar 2003 Start-up: First concentrate feed July 2003 All design parameters met, steady state operation

Four years from first testing to commercial demonstration

28 2006 Phelps Dodge Corporation

Bagdad Concentrate Leach Plant Schematic

PLS Pond andSX/EW

SlurryStorage

Tank

ConcentrateSlurry PLV

FeedTank

PLVPLV

CCD #1

FlashVesselFlash

Vessel

StrongPLSTank

Neut#1

Neut#2

Neut#3

Neut#4

Tails

CCD #2CCD #3CCD #4

#1

SCRUBBER

#2

SCRUBBER

PLS to SX/EW and Cathode Production

29 2006 Phelps Dodge Corporation

Bagdad Concentrate Leach Plant

August, 2003

30 2006 Phelps Dodge Corporation

Pressure Leaching Vessel at Bagdad

31 2006 Phelps Dodge Corporation

Solid-liquid Separation at Bagdad

August, 2003

32 2006 Phelps Dodge Corporation

Bagdad Concentrate Leach Plant Copper Production

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

3,500,000

4,000,000

Mar-0

3Ap

r-03

May-0

3Ju

n-03

Jul-0

3Au

g-03

Sep-0

3Oc

t-03

Nov-0

3De

c-03

Jan-0

4Fe

b-04

Mar-0

4Ap

r-04

May-0

4Ju

n-04

Jul-0

4Au

g-04

Sep-0

4Oc

t-04

Nov-0

4De

c-04

P

r

o

d

u

c

t

i

o

n

(

l

b

s

)

Production (lbs) Design Basis Production

33 2006 Phelps Dodge Corporation

Phelps Dodge Concentrate Leaching Milestones (continued)

May 2004 Conversion of Bagdad demonstration plant to medium temperature process started

May 2005 Start-up: medium temperature and direct electrowinning (MT-DEW) process

Dec 2005 Completion of MT-DEW process demonstration 2Q 2007 Scheduled completion of Morenci facility

34 2006 Phelps Dodge Corporation

Bagdad MT-DEW Process Conversion Super-fine Grinding

35 2006 Phelps Dodge Corporation

Direct Copper Electrowinning at Bagdad, AZ

36 2006 Phelps Dodge Corporation

Morenci Concentrate Leaching Application

Provides economically viable alternative to smelting and refiningyGenerates by-product acid for leachingyEliminates freight cost for concentrate shipments and acid

deliveriesyDecouples Morenci from smelter balance dependency yReduces Morencis mill conversion costs

Morenci Western Copper concentrate mineralogy yMixed chalcopyrite, covellite, chalcocite, pyrite

Medium temperature and direct electrowinning (MT-DEW) process selectedyBest fit with Morenci concentrate production and acid balanceyUtilize existing EW and SX capacity at Morenci

Copper production capacity = 75,000 tons per year Copper recovery slightly higher than smelting and refining

37 2006 Phelps Dodge Corporation

Production Decisions Impacted by Concentrate/Acid Balance

Chino Smelter650,000 tpy capacity

(off line)

North American Concentrate Bagdad Sierrita Chino (partial capacity) Cobre Morenci (off line)

North American Leach Morenci Bagdad Sierrita Chino Tyrone (partial capacity) Miami (partial capacity)

External acid

source

Candelariaconcentrate

External acid

consumer

Miami Smelter750,000 tpy capacity

(operating)

External concentrate

source

38 2006 Phelps Dodge Corporation

Morenci Concentrate Leaching Facility 3D Model View

39 2006 Phelps Dodge Corporation

Other Developments Affecting Copper Hydrometallurgy

Material Characterization Comminution Alternative Products

40 2006 Phelps Dodge Corporation

High-Pressure Grinding Rolls

Cerro Verde milling circuit to include high pressure grinding rolls (HPGR) instead of SAG mills

Prosy Higher throughputy Greater energy efficiencyy Greater flexibilityy Lower unit cost

Consy Additional capital cost

Financial Impacty Significantly reduces power

consumption and unit production costs

Note - Use yellow to highlight font colors

(but never titles)

41 2006 Phelps Dodge Corporation

Material Characterization QemSCAN Technology

42 2006 Phelps Dodge Corporation

New Copper Products

Copper powder technologyy Potential replacement for cathode

to rody Specialty copper powders

Copper powder process reduces or eliminates the following: yManual harvesting of cathodesyCell cleaningy Stainless blank repairs and

replacementy Stripping machinesy Slippery or brittle cathodes

Focused on reducing costs and improving process safety and efficiency

PDC proprietary technology Demonstration plant in operation at

Morenci, AZ

43 2006 Phelps Dodge Corporation

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

Thank You

Recent Developments in Copper HydrometallurgyJohn O. MarsdenSenior Vice President, Technology & Product DevelopmentOutlineSafetyPhelps Dodge Long Track Record of Technology DeploymentSolution Extraction and ElectrowinningSolution Extraction and Electrowinning at Bagdad, ArizonaSolution Extraction & ElectrowinningExample of Technology Transforming Copper ProductionMorenci Modoc SX PlantKoch Solution Extraction In-Pipe ReactorBiologically Enhanced LeachingCerro Verde Leach Pad 4 - Grasshopper StackerMorenci Mine-for-Leach Agglomeration DrumsMorenci Mine-for-Leach North StackerLeaching Developments Bacterial AugmentationAdvanced Modeling to Improve Heap PerformanceEnhanced Chalcopyrite Leaching Bagdad Crystal MountainMorenci Enhanced Stockpile LeachingConcentrate Leaching Alternative to Smelting & RefiningCopper Extraction in 1980s and 1990sConcentrate Leach Technology Replaces Smelting/RefiningCopper Concentrate Leaching HistoryCopper Concentrate Leaching HistoryCopper Concentrate Leaching More Recent DevelopmentsPhelps Dodge Concentrate Leaching MilestonesBagdad Concentrate Leach Plant SchematicBagdad Concentrate Leach PlantPressure Leaching Vessel at BagdadSolid-liquid Separation at BagdadBagdad Concentrate Leach Plant Copper ProductionPhelps Dodge Concentrate Leaching Milestones (continued)Bagdad MT-DEW Process Conversion Super-fine GrindingDirect Copper Electrowinning at Bagdad, AZMorenci Concentrate Leaching ApplicationProduction Decisions Impacted by Concentrate/Acid BalanceOther Developments Affecting Copper HydrometallurgyHigh-Pressure Grinding RollsMaterial Characterization QemSCAN TechnologyNew Copper ProductsThank You