Copper ore may be sulfide, oxide or mixed mineralogy. Sulfide ores often require grinding and preparation for flotation, whereas oxide ores may follow leach-based routes, so there is no universal copper-ore flowsheet.
- Common sulfide mineral
- Chalcopyrite
- Main distinction
- Sulfide, oxide or mixed ore
- Grinding objective
- Liberate valuable mineral from gangue
Why separate sulfide and oxide copper ores?
Sulfide minerals such as chalcopyrite, bornite and chalcocite have different surface chemistry and recovery behaviour from oxide copper minerals. Circuit selection based on copper grade alone is therefore unreliable without mineralogy.
Mixed ores can introduce additional effects from oxidation degree and fine gangue on grinding and downstream beneficiation.
What is the grinding circuit trying to achieve?
For a sulfide ore, grinding commonly aims to liberate copper minerals from gangue and associated sulfides such as pyrite. The target size distribution should reduce locking while limiting unnecessary fines.
Where closed-circuit classification is used, circulating load, classifier behaviour and sampling points are evaluated as one system.
How should flotation or leaching information be used?
Flotation is common for sulfide copper ores, while oxide ores may use different leach routes. That downstream information defines what the preparation circuit must deliver.
The preparation circuit should deliver the particle-size and feed conditions required by the downstream flotation or leach route; final technology selection depends on mineralogical and metallurgical testwork.
Ore-preparation inputs
- Copper mineral species and oxidation degree
- Pyrite and gangue mineralogy
- Feed PSD and moisture
- Liberation target and grindability
- Downstream beneficiation tests and product specification
