Metallurgical Evaluation of the Wemco SuperCell™

Flotation 2009Cape Town11th Nov 2009

M. Dunn - Rio TintoD. Lelinski, A. Weber, B. Dabrowski and F. Traczyk – FLSM

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Presentation Overview

Introduction - The application at KUC

Introduction - SuperCell™

Metallurgical Test Design

WEMCO Metallurgical Results

Conclusions

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Kennecott Utah CopperCopperton Concentrator

56 Mtpa Throughput

SABC circuit

Bulk Cu/Mo flotation

Moly separation

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Copperton Bulk Flotation Flowsheet

Bulk Concentrate

TailingsScavengerRougher

Flotation Feed

Rougher CleanerColumns

Rougher Regrind

ScavengerRegrind

ScavengerCleanerColumns

Cleaner Scavenger

ScavengerMechanical Cleaner

SuperCell™

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Opportunity at KUC

• Additional Scavenger Cleaner capacity required

– Improve copper & moly recovery

– Reduce re-circulating load

• Mechanical cells have proven recovery performance

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Project Objectives

Start-up Production Cell WEMCO Jan 2009

Start-up Test Cell Dorr-Oliver Apr 2009

Retro-fit Test Cell XCELL Sep 2009

Final Configuration

Dec 2009

KUC • Achieve design recovery and grade

• Accelerated delivery

FLSM • Demonstrate SuperCell™ in operation

• Validate hydrodynamic and metallurgical scale-up

Scope • Test cell installed on a “try before buy” basis

• 9 month testing program with 3 mechanisms

• KUC purchased additional cell for continuous production

Design/Construct Production Cell

Sep 2008

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WEMCO

300

Dorr-Oliver

330

XCELL

350

FLSmidth Flotation Machines

8.6m

6m

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FLSmidth SuperCell™ Mechanisms

WEMCODorr-Oliver

XCELL

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WEMCO Hydrodynamic Testing

• Machine ParametersSubmergence

Rotor Speed

Rotor Engagement

• Measured ResponseMachine Power

Aeration Rate

Pulp Circulation

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Metallurgical Testing Program

• 4-5 test campaigns on each mechanism

• Same machine parameters for each campaign

• Difference between campaigns related to changes in feed

– Regrind size

– Flowrate

– Ore type

• Pilot testing campaign in parallel to full-scale

• Lab flotation kinetics tests for each campaign

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Pilot Scale Testing

• 1.5m3 pilot cell operated in parallel to SuperCell™ for scale-up

• Evaluated residence time effect on parameters

• WEMCO, Dorr-Oliver and XCELL pilot cells operated in parallel

• Facilitated comparison between full-scale mechanisms

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Metallurgical Test Matrix - WEMCO

Machine ParametersFroth Depth

Rotor Speed

Measured ResponseFeed Assay

Concentrate Assay

Tailings Assay

Aeration Rate

Absorbed Power

Feed rate

Solids Content

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Metallurgical Test MatrixDorr-Oliver/XCELL

Machine ParametersFroth Depth

Rotor Speed

Air Rate

Measured ResponseFeed Assay

Concentrate Assay

Tailings Assay

Aeration Rate

Absorbed Power

Feed rate

Solids Content

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Wemco Supercell™ exceeded performance guarantee

50.055.060.065.070.075.0

80.085.090.095.0

100.0

10.0 20.0 30.0 40.0

Cu Grade

Cu Recovery

1st Campaign

2nd Campaign

3rd Campaign

4th Campaign

5th Campaign

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2nd Campaign: Similar results

50.055.060.065.070.075.0

80.085.090.095.0

100.0

10.0 20.0 30.0 40.0

Cu Grade

Cu Recovery

1st Campaign

2nd Campaign

3rd Campaign

4th Campaign

5th Campaign

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3rd Campaign: Regrind Mill off

50.055.060.065.070.075.0

80.085.090.095.0

100.0

10.0 20.0 30.0 40.0

Cu Grade

Cu Recovery

1st Campaign

2nd Campaign

3rd Campaign

4th Campaign

5th Campaign

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4th Campaign: Low feed gradeHigh feed rate

50.055.060.065.070.075.0

80.085.090.095.0

100.0

10.0 20.0 30.0 40.0

Cu Grade

Cu Recovery

1st Campaign

2nd Campaign

3rd Campaign

4th Campaign

5th Campaign

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5th campaign: Response on Skarn ore

50.055.060.065.070.075.0

80.085.090.095.0

100.0

10.0 20.0 30.0 40.0

Cu Grade

Cu Recovery

1st Campaign

2nd Campaign

3rd Campaign

4th Campaign

5th Campaign

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Moly Recovery: a function of power

Specific Power

60.0

65.0

70.0

75.0

80.0

85.0

90.0

95.0

100.0

0.50 0.60 0.70 0.80 0.90 1.00

Specific Power, kW/m3

Mo Re

covery

1stCampaign2ndCampaign4thCampaign

2020

Developed Response Surfaces

SuperCell

Feed Flow 3231 gpm (22.1 min RT) 49.7 gpm (7.2 min RT)

Ore Type Type 2 Type 2

Cu Feed Grade 10 % 10 %

Pilot Cell

• All campaign results were statistically significant

• Developed response surfaces for pilot vs full-scale

• Enables scale-up to be determined

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Mo Recovery: a function of power

Power

• Can achieve design recovery at 0.8kW/m3

• Higher energy will improve recovery further

Mo Recovery

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Similar response with Cu

Power Cu Recovery

Feed Flow 3231 gpm (22.1 min RT)

Ore Type Type 2

Cu Feed Grade 10 %

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Able to quantify metallurgical trade-off between recovery and grade

SuperCell Pilot Cell

Operations able to optimize operating conditions

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Conclusions

• SuperCell exceeded design performance

• DoE determined optimum operating conditions

• Recovery improves with higher specific power input

• Success factors for plant experimental testwork:

– Circuit designed for plant stability and sampling

– Robust experimental design

– Focus on quality of sampling and prep

• FLSM - foundation for new scale-up method based on pilot vs full-scale response surface

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Questions?