AN OVERVIEW OF TAILINGS MANAGEMENT SYSTEM SELECTION

• OBJECTIVE:– Provide Guidance– Encourage Discussion– Discuss Custom

Assessment of Tailings Management Systems

• THE PRESENTATION:– Focus on Wet-Wash

Extractive Mines– Overview of Tailings

Management Technologies

TAILINGS SYSTEM SELECTION

• BENEFITS TO ATTENDEES:– Broader view of what

solutions are available for Tailings Management

– Improved understanding of the solutions are best used

– Perspective into the sorts of results achievable from each unit process

– Perspective into the Capital and Expenditure issues of each unit process

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PRESENTATION STRUCTURE

1. Tailings System Selection

2. Now and Then - Bridging the Gap:a) Thickenersb) Filter and Pressesc) Alternative Methodsd) Chemicals

3. Summary

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TAILINGS SYSTEM SELECTION

• In general, it costs more in the long run to NOT deal with tailings thoughtfully, from the beginning

• The right investment into the right Tailings Management System will maximise profit over the Life of the Mine

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TAILINGS SYSTEM SELECTION – IN A NUTSHELL

Current Situation

(Profit 1)

Desired Situation

(Profit 2)

Several Solutions

Best Solution

GAP

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BRIDGING THE ‘GAP’

• Every Mine is unique:– Tailings-Site-Business combination

• There is a unique solution for every Mine

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BRIDGING THE GAP

• Capital and Equipment:– Dams/voids/bunds/cells– Tanks– Mobile Equipment

• Loaders, trucks, screens, etc

– Conveyors– Pumps– Piping– Mixers/Agitators– Washery Equipment– Thickeners and Clarifiers– Filters and Presses– Automation– Chemical Equipment– etc

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BRIDGING THE GAP

• Consumables:– Power and Fuel– Labour– Chemicals– Earthmoving– Replacement parts– Maintenance– Technical support– etc

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BRIDGING THE GAP – SPECIFIC TOOLS

• Thickeners

• Filters and Presses (Dewatering)

• Alternative Unit Processes

• Chemical Additives

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THICKENERS – TYPICALS…Quarries typically 2-8% solids (w/w), depending on

fine-sand Recovery

Quarries typically 20-65% solids (w/w)

Clean Process Water

< 0.2% solids (w/w)

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THICKENERS

• The ‘smarts’:– Rake selection and design– Centre-well design– Chemical program selection, design and support

• Poor selection and operation can:– Decrease achievable underflow density– Add to production downtime and

reduced throughput – Reduce the achievable thickener throughput – Increase Opex requirements

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THICKENERS• The use of settling and clarity

aids (flocculants, coagulants):– Critical to most modern

thickener designs– Reduce capital

requirement/footprint– Add ‘robustness’ to operation– Allows for a smaller water

circuit– Improved water quality

Flocculant Dose

Unit Area

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FILTERS AND PRESSES (DEWATERING)

• Mechanical Pressure:– Plate and Frame– Recessed Plate– Belt-Press Filter– Screw Press– Disc Press– Roll Press– Tube Press

• Positive Fluid Pressure:– Horizontal Plate– Pressure Leaf– Tubular Filters– Centrifugal

Discharge

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FILTERS AND PRESSES (DEWATERING)

• Negative Fluid Pressure (Vacuum):– Rotary Drum– Rotary Disc– Horizontal Table– Scroll Discharge– Pan Filter– Tilting Pan Filter– Horizontal Belt-Filter

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ALTERNATIVE THICKENING AND DEWATERING PROCESSES

• Centrifugation

• Chemical-Only In-Line Tailings Stacking

• Cyclonic Separation

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FILTERS, PRESSES AND ALTERNATIVE METHODS

• Chemical Treatment:– Most filter/press

applications benefit from some sort of chemical modification of the feed slurry

– Wide range of specialty chemical programs available

– Involve your chemical supplier in the Tailings System evaluation process

Treated slurry on the gravity drainage zone of a belt-press application at a quarry

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FINAL SUMMARY• A general rule:

– It takes a certain amount of something to do anything– What you don’t put in as capital, needs to be put in as

consumables– What you don’t put in as consumables need to be put

in as space and time• Know where you are• Know where you want to be and what it will

mean to you• There are many Tools to get you where you want

to be• Understand (quantify) the value of where you

want to beSlide 17 of 17