Mine Based Pre-Concentration

1. Mine Based Pre-Concentration Ben Murphy Cobar Mining Seminar - 9th August 2010

2. Overview • Introduction – Technology & Challenges • Lean Mining and Waste Elimination • Pre-concentration – Suitability and technology • The Python Concept

5. Mining Sector Issues • Few “simple mining and metallurgy” large ore bodies left • Existing ore bodies –deeper and increasing complexity • Escalating capital on large fully engineered plants • High costs around developing smaller ore bodies • Long environmental permitting • Power and water supply issues “Economies of Scale are great but what if the ore body is simply not big enough?”

6. Lean Mining Analysis Over Processing Overproduction Waiting Inventory Transportation Motion Defects The Seven Wastes

7. Lean Mining Applied (McCarthy, 1999)

8. Mine Based Pre-concentration Integrated UG Mining and Processing System Model (Bamber, 2004)

9. Pre-concentration Benefits • MINIMISE DISTANCE TO MINING • MAXIMISE WASTE REJECTION TO MAXIMISE BENEFIT • Reduced transportation costs • Haul distance – smaller equipment / less energy • Haul Mass – smaller equipment /less energy • Smaller Inventories • Smaller higher value stockpiles • Over processing • Valuable losses to fines • Savings in power and chemicals

10. Pre-concentration Benefits • Savings on mining costs of 20-50% • Numerous studies in the literature to support this; • Bamber et al • Lane, Fountain & Brooy • Dominy, Gray & Daffern

11. Pre-concentration Benefits • In addition • May allow alternate mining methods (narrow vein) • Backfill opportunities • Permitting benefits • May allow mining of small satellite ore bodies (surface) • Increase mine life – expand reserves “For successful application integration into mining systems is critical”

12. Pre-concentration Technology • Pre-concentration not a new thing • A rose by any other name…….. • Often applied at front end of the plant Decreasing Grade

13. Pre -concentration Technology (Bamber, Klien, Morin, Schoeble, 2005)

14. Suitability to Pre-concentration • High grade into low mass – high gangue rejection • Coarse liberation • Mineralogical examination and lab test work

15. Yield-Recovery Concept

16. Pre-concentration Methods • Size Scalping and screening • Density Dense Media or Gravity • Colour / Fluorescence Optical / x-ray sorter • Magnetism Magnetic Separators • Surface Chemistry Coarse Flotation • Radioactivity Radiometric Sorters

17. Optical Sorting Flowsheet (Bamber, Klien, Schoeble, 2006)

18. Gravity - Flotation Flowsheet

19. Mine Based Case Studies Selected Case Studies from Literature * Operational Mine Based Pre-concentration sites

20. Python – The Concept Design Envelope Fit in an UG drive Transportable Minimal Civils Plug’n’play Low water Low power

21. Python – The Concept Designed for mobility and flexibility Pre-concentration focus 13 Modules including MCC’s 5 dry modules, 6 wet modules, 2 electrical

22. Python - The Reality

23. Mine Based Preconcentration • Has the ability to provide step change improvements by; • Reducing mine transport costs • Reducing Inventories • Reducing Over processing • To maximise its potential it is important to; • Minimise the distance from mine to plant • Maximise the waste rejection • Potential savings of 20-50% of the mining costs

24. “Damit,….I don’t have time for this sales man, I Have a war on my hands”

29. Vertical Shaft Impactor (VSI) • Rock fed into the top of the machine. • Feed accelerated, leaves rotor at 60 m/s. • Rock on rock crushing • Handle large variation in moisture content, ideally suited wet screened products • Can handle multiple feed sizes (30:1 reduction ratio)