This report details the proposed processing facilities for the Copper Creek Project, encompassing a flotation circuit for transitional and sulphide materials and a heap leach with solvent extraction-electrowinning (SX/EW) for oxide materials.
Report context
This technical report and preliminary economic assessment, dated May 3, 2023, describes the recovery methods proposed for the Copper Creek Project. It details two process flowsheets developed to treat the mineralized materials from the various Copper Creek deposits.
Processing route
Overview
Based on past metallurgical laboratory testing and process design expertise, two flowsheets have been developed. The main process will beneficiate copper, molybdenum, and silver from both transitional and sulphide materials by froth flotation. The second process will extract copper from oxide materials by heap leaching with solvent extraction and electrowinning to produce copper cathode.
Flotation
This process is designed to treat 345 Mt of mineralized material at a nominal rate of 30,000 t/d. The flotation flowsheet includes primary crushing, SAG and ball milling, bulk rougher flotation, regrinding, cleaner flotation, molybdenum separation flotation circuit, copper and molybdenum concentrate thickening and filtration, and tailings thickening and filtration.
The process design includes primary crushing near the pit boundary, with run-of-mine feed reduced to 80 percent passing 95 mm. The SABC circuit consists of a SAG mill feed conveyor, SAG mill, pebble cone crusher and conveyors, ball mill, cyclone cluster, lube room, electrical room, and control room.
Molybdenum Flotation
The molybdenum flotation circuit will consist of three conditioning tanks, rougher flotation, scavenger flotation, and five stages of cleaner flotation. The circuit uses self-aspirated cells with specific cell volumes for each stage. Concentrate from the fifth stage of cleaning will flow by gravity to the molybdenum concentrate thickener.
Copper Concentrate Handling
Copper concentrate will be thickened to approximately 60 percent solids in the high-rate copper concentrate thickener. The concentrate filter will be a horizontal press filter, producing filter cake at 8 percent moisture. Filter cake will discharge to a covered concentrate loadout stockpile.
Tailings Handling
Flotation tailings will be thickened to approximately 60 percent solids and filtered using horizontal plate and frame filters. Tailings filter cake, containing 15 percent moisture, will be conveyed to the dry tailings primary stacking system.
Reagents
Reagents for flotation include lime for pH control, fuel oil as an enhancer, Aerophine 3418A as a collector, methyl isobutyl carbinol as a frother, sodium hydrosulphide as a copper depressant, and flocculant for sedimentation.
Heap Leach SX/EW
This process will treat 20 Mt of mineralized oxide material at a nominal rate of 6,850 t/d. The leaching flowsheet includes primary, secondary, and tertiary crushing, agglomeration and stacking, leaching, solvent extraction, and electrowinning.
Oxide material will be crushed to 80 percent passing 13.5 mm. Agglomeration will be conducted in a single rotating rubber lined drum with sulphuric acid and raffinate sprayed into the drum. The leach pile will be irrigated with acidified raffinate, with pregnant leach solution reporting to the PLS pond.
Copper will be extracted from PLS using two solvent extraction mixer/settlers in series. Rich electrolyte will be heated and pumped to electrowinning cells where metallic copper will be plated onto cathode sheets. Reagents for the heap leach SX/EW operation include sulphuric acid, diluent, copper extractant, and materials for crud management.
Key reported parameters
| Parameter | Unit | Value | Basis |
|---|---|---|---|
| Total flotation feed | Mt | 345 | Design |
| Flotation rate | t/d | 30,000 | Design |
| Copper feed grade | % | 0.78 | Design |
| Copper recovery | % | 94.4 | Design |
| Silver feed grade | g/t | 5.56 | Design |
| Silver recovery | % | 78.1 | Design |
| Molybdenum feed grade | g/t | 158 | Design |
| Molybdenum recovery | % | 83.3 | Design |
| Sulphide rougher feed P80 | µm | 190 | Design |
| Transitional rougher feed P80 | µm | 160 | Design |
| Total heap leach feed | Mt | 20 | Design |
| Heap leach rate | t/d | 6,850 | Design |
| Heap leach product size P80 | mm | 13.5 | Design |
| Copper grade (oxide) | % | 0.38 | Design |
| Copper recovery (oxide) | % | 75 | Design |
| Gangue acid consumption | kg/t | 20 | Design |
| Crusher product size P80 | mm | 95 | Design |
| SAG mill specific energy | kWh/t | 9 | Design |
| Ball mill specific energy | kWh/t | 7 | Design |
| Regrind circuit product size P80 | µm | 31 | Design |
| Final Cu concentrate grade | % Cu | 30 | Design |
| Tailings filter cake moisture | % (w/w) | 15 | Design |
| Final Mo concentrate grade | % Mo | 50 | Design |
| SAG mill media consumption | kg/t | 0.275 | Estimated |
| Ball mill media consumption | kg/t | 0.255 | Estimated |
| Fresh water consumption | m³/h | 200 | Estimated |
| Current efficiency (SX/EW) | % | 90 | Design |
Project website: https://faradaycopper.com/projects/copper-creek-project/overview/
Technical qualifications
The reported values and descriptions represent design criteria and estimates based on metallurgical laboratory testing and process design expertise. Comminution parameters were determined using test results from the most recent ALS test work program. Specific historical operating data for the Copper Creek Project is not presented in this section of the report.
Source: Copper Creek Project, NI 43-101 Technical Report and Preliminary Economic Assessment, May 3, 2023, Section 17: Recovery Methods.
