Overview
The Pueblo Viejo processing plant is designed to treat 24,000 tonnes per day of refractory gold-silver ore through an advanced pressure oxidation (POX) circuit. This complex facility represents one of the world’s most sophisticated mineral processing operations for refractory ore treatment.
Key Process Stages
- Crushing: Primary gyratory crusher reduces ROM ore to P80 of 130mm
- Grinding: SABC circuit (SAG mill with pebble crusher + ball mill) achieves P80 of 80μm
- Pressure Oxidation: 4 autoclaves operate at 225°C and 3,100 kPag with 60 min retention
- Hot Cure: 12-hour retention at >90°C to dissolve basic ferric sulfate
- CCD Washing: 3-stage counter-current decantation removes dissolved metals
- Lime Boil: Jarosite breakdown at >85°C to liberate silver
- CIL Circuit: Carbon-in-leach cyanidation for gold/silver recovery
- Refining: Zadra elution, electrowinning, and smelting to produce doré bars
- Tailings Treatment: INCO cyanide destruction and HDS neutralization
Critical Data
| Parameter | Value |
|---|---|
| Design Throughput | 24,000 tpd |
| Oxygen Plant Capacity | 4,152 tpd |
| Sulfide Sulfur Processing | 80 tph |
| SAG Mill Power | 16,400 kW |
| Autoclave Operating Pressure | 3,100 kPag |
| CIL Leach Recovery (Au) | 35% |
| Total Lime Consumption | 47-75 kg CaO/t ore |
| Power Consumption | 210 MW (steady-state) |
Expansion Features
The expansion project increases capacity to 14 Mtpa through:
- New primary crusher and single-stage SAG mill
- Parallel flotation circuit for ore upgrading
- Flash thicken recycle (FTR) autoclave modification
- Additional oxygen plant capacity (3,000 tpd)
- Float tails CIL circuit for additional recovery
Water Management
The plant features comprehensive water treatment with:
- 3,340 m³/h TSF reclaim water
- 6,574 m³/h effluent treatment capacity
- 50m diameter clarifiers for neutralization
- Guaranteed 1,655 m³/h minimum discharge to Margajita River
