Overview
The Los Ricos South (LRS) process plant is designed to treat 2,000 tonnes per day of ore to produce doré as final product and a copper sulphide concentrate secondary product. Located at the mine site, the facility receives run-of-mine ore from underground operations, employing conventional unit operations including crushing, grinding, leaching, and Merrill Crowe precipitation.
Key Process Stages
- Primary Crushing: Metso C106 jaw crusher reduces ROM feed from 250mm to 72mm (k80)
- Grinding: Single-stage SAG mill (7.3m x 4.27m, 3,600 kW) in closed circuit with cyclones produces 74µm product
- Leaching: Four 15.4m x 16.8m agitated tanks with 96 hours residence time at 55% w/w solids
- CCD Circuit: Five-stage counter-current decantation with 99% wash efficiency
- Merrill Crowe: Zinc precipitation achieves 98% Au and 98.5% Ag recovery
- SART Plant: Recovers 90% of copper while regenerating cyanide
- Tailings: SO2/air detoxification followed by pressure filtration to 16% moisture
Critical Data
| Parameter | Value |
|---|---|
| Annual Throughput | 0.72 Mtpa |
| Daily Throughput | 2,000 tpd |
| Design Head Grade (Au) | 2.98 g/t |
| Design Head Grade (Ag) | 344 g/t |
| Overall Au Recovery | 93.1% |
| Overall Ag Recovery | 87.3% |
| SAG Mill Power | 3,600 kW |
| Leach Residence Time | 96 hours |
| Tailings Moisture | 16% w/w |
Reagent Consumption
| Reagent | Annual Usage (tpa) |
|---|---|
| Sodium Cyanide | 1,036 |
| Hydrated Lime | 4,767 |
| Sodium Hydrosulphide | 996 |
| Sulphuric Acid | 4,482 |
| Zinc Powder | 211 |
Based on filing data from 2024-2025.
