Overview
The Westwood Mine processing facility is a refurbished version of the original Doyon Mill from the 1970s, upgraded between 2011-2013 to efficiently process Westwood ore. The plant features modernized grinding, leaching, adsorption, and stripping circuits, with enhanced cyanide destruction capacity and a new paste backfill plant to support underground operations.
Key Process Stages
- Ore Handling: Underground ore is trucked 2.5km to the crusher house, processed through a single-stage jaw crusher (1.07 x 1.22 m) with grizzly feeder
- Grinding: 2,700 HP SAG mill in closed circuit with hydrocyclones, feeding a 1,000 HP ball mill. Target grind size: 80% passing 53 microns
- Gravity Separation: Sweco screen, 30″ Knelson concentrator, and shaking table recover gravity gold concentrate
- Leaching: 55-hour total retention time across primary leach (4.7h), CIL (6.6h), secondary leach (31.3h), and CIP (12.1h) tanks
- Cyanide Destruction: SO2/Air process with parallel detox reactors and 14-hour buffer capacity for backfill operations
- Paste Backfill: Dual-circuit system with 2km pipelines, designed for 144.6 tph capacity (operating at 70 tph)
- Gold Recovery: Zadra stripping reactors, two electrowinning cells, and carbon regeneration kiln producing doré bars
- Tailings: Disposal in Doyon open pit with partial usage for paste backfill
Critical Data
| Parameter | Value |
|---|---|
| Annual Throughput | 1,100,000 tonnes |
| Mill Availability | 96% |
| Daily Processing Rate | 3,106 tpd |
| Power Consumption | 8% of milling costs |
| Water Treatment | 4.0-4.5 MCUM annually |
Key Reagent Consumption (Annual)
| Material | Quantity (kg) |
|---|---|
| Grinding Media | 1,805,000 |
| Quick Lime (Total) | 5,640,000 |
| Cyanide | 945,000 |
| SO2 | 1,118,000 |
| Slag/Cement | 8,273,000 |
