Overview
The Ikkari Project processing plant is a comprehensive gold recovery facility designed to process 3.5 million tonnes per annum (3,500 t/d nominal) of ore from the open pit operation. The plant incorporates crushing, grinding, gravity separation, carbon-in-leach (CIL), and cyanide destruction circuits, utilizing proven technologies to achieve an overall gold recovery of 95.8%.
Key Process Stages
- Comminution Circuit: Single-stage crushing (jaw crusher to P80 155mm) followed by SABC grinding circuit (8.5m x 4.25m SAG mill + 6.0m x 10.5m ball mill) producing P80 100µm product
- Gravity Recovery: 37.5% of cyclone underflow processed through two gravity concentrators with intensive cyanidation (29.3% gold recovery)
- CIL Circuit: Seven 16m x 16.5m tanks (24h retention time) achieving 94.9% gold recovery
- Gold Recovery: Pressure Zadra elution (12t/d carbon capacity), electrowinning, and refining to produce doré
- Tailings Management: SO2/Air cyanide destruction followed by pressure filtration (2x 1150m² filter presses) producing 87.5% solids cake
Critical Data
| Parameter | Value |
|---|---|
| Design Throughput (annual) | 3.5 Mt/a |
| Nominal Throughput (daily) | 9,589 t/d |
| Max Daily Throughput | 11,986 t/d |
| Average Gold Grade | 2.28 g/t |
| Bond Work Index | 16.1 kWh/t |
| SAG Mill Power | 6,400 kW |
| Ball Mill Power | 6,800 kW |
| Overall Gold Recovery | 95.8% |
| Gravity Recovery | 29.3% |
| CIL Recovery | 94.9% |
| Leach Retention Time | 24 hours |
| Tailings Production | 434.3 t/d |
Circuit Highlights
The plant features several notable design elements including a pebble crusher in closed circuit with the SAG mill, intensive cyanidation of gravity concentrates, and a complete cyanide destruction system. The filtration plant produces stackable tailings for co-disposal during open pit operations, with provisions for underground paste backfill later in mine life.
Future Adaptations
When throughput reduces to 2.0 Mt/a during underground operations, the plant will operate with modified parameters including reduced ball charges, lower mill speeds, and potential bypass of some equipment units while maintaining gold recovery performance.
Based on filing data from 2024-2025.
