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Final presentation
- 1. Barrick Goldstrike Team 5/1/15 •Justin Brick • Jack Blaisdell • Jordan Dick • Devin Rowe
- 2. Overview • Introduction-Project Statement •Design approach • Results • Economic calculation and implications • Video progress • Tasks to finish • Things to do differently
- 3. Project Statement Design amineral processing circuit that will liberate the most and/or maximize the concentration of gold from Barrick’s Goldstrike dam tailings and create a flowsheet of the circuit. Determine the net present value (NPV) of the total amount of gold that will be liberated and/or concentrated Calculate an estimated initial rate of return (IRR) of the process.
- 4. Quick Facts • NorthBlock Dam is one of the largest rockfill tailings dam in the world • Goldstrike mine can process 30,000 tones of gold ore per day • 170 million tones of tailings stored in the North Block Dam
- 5. Design Approach Determine abase line analysis of tailings • Current grade and particle sizes • Mineralogy • Liberation Fraction Concentrate the tailings and analyze results • Concentration methods may be froth flotation, magnetic and gravity separation • Use atomic absorption spectroscopy (AAS) to determine the grade after each method • Fire assays done as often as AAS to confirm results Design flowsheet and determine implications • NPV and IRR.
- 6. Completed Results Mineralogy • Mostlysilicates, magnetic component is maghemite Initial grade of tailings • Grade 0.038 Toz/ton Gold • 6.46 million Toz gold present, current value about $8.4 billion Gravity separation • Wave table was used • About 2000 grams of tailing were processed • Only about 90 grams of concentrates recovered • Grade of concentrates were lower than initial grade
- 7. Results continued Froth Floation •Targeted towards carbonaceous material • 4 tests: Natural, Frother , Oleic Acid, and Frother + Oleic acid • All surfactants were added at 0.268 lbs/ton • Only Oleic acid test had gold, but flake was too small to weigh Magnetic separation • Targeted 3-5 wt% - attained 7 wt% • Fire assay 0.48 Toz/ton Gold, 88% recovery • Contact at Barrick, Wet magnetic separation results: 0.2 Toz/ton
- 8. Costs Annual • Autoclave andacid leach • Facility and dredger horse power • Maintenance • Salaries • Lighting and AC • Power and horse power for dryer (dry process) Profit Annual • Gold Initial • Facility construction • Dredger • Fluidized bed dryer (dry process)
- 9. Economic calculations forDry process Initial Costs $ Annual costs $ Annual profits $ Facity construction 210000000 Autoclave and acid 70956000 Gold 368971200 Dredger 2000000 Facitity's hp 470327.8233 Fluid bed dryer 21875000 personel salaries 1200000 Dredger hp 2660958.048 maintenance 1084629.706 Lighting 117761.28 AC 3751392.505 Dryer hp 39193.98527 Dryer power 20440000000 Totals 233875000 20520280263 368971200 NPV -$165,000,000,000.00 IRR -5.27E+21%
- 10. Economic calculations forWet process Initial Costs $ Annual costs $ Annual profits $ Facity construction 210000000 Autoclave and acid 70956000 Gold 153738000 Dredger 2000000 Facitity's hp 470327.8233 personel salaries 1200000 Dredger hp 2660958.048 maintenance 983181.1769 Lighting 117761.28 AC 3751392.505 Totals 212000000 80139620.83 153738000 NPV $390,000,000.00 IRR 33.1%
- 11. Economic details andassumptions discount rate (I) 0.05 number of years 10.78132927 $/kWh 0.06 operates 80% of year 0.8 Tailings (tonage/day) 54000 Concentrates wt%/100 0.05 kW/hp 0.745699872 personel 8 ore grade gold (tOz/ton) wet 0.2 gold recovery %/100 0.75 gold price $/troy 1300 Facitity's hp 1500 Dredger hp 8486.5 autoclave & acid $ /ton 90 personel salaraies/year 150000 Maintenance %total cost/100 0.05 AC power kW based on square footage 8921.690699 lighting power consumption ($/year) 117761.28 square footage 2178000 dryer hp 5 Dryer Power BTU 1E+12 BTU/ton coal 24000000 $/ton coal 70 ore grade gold (tOz/ton) dry 0.48
- 12. Flowsheet, NPV andIRR NPV = $390 million IRR = 33.1%
- 13. Video • Filmed eachof our experiments • Able to interview Wayne Douglas • Created in Windows Movie Maker
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- 15. Tasks to Complete •Complete and turn in individual assignments • Finish design paper • Conclude editing of the video
- 16. What we wouldhave done differently • Spend more time on froth flotation -Ignore carbonaceous material -Focus on creating a two-three stage flotation for maghemite • Try to perform a wet magnetic separation test
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