Minerals processing techniques
From BioMineWiki
The metal bearing material (especially ore) is generally pretreated prior to leaching to optimize the metal recovery. Pretreatment operations include one or several operations such as:
- Crushing/grinding to increase the surface area and also liberate value minerals from gangue. Blasting is a special case for in-situ mining to increase the permeability for leaching reagents to access the ore.
- Agglomeration of fine particles into bigger agglomerates is used in heap leaching operations to increase permeability.
- Concentration by flotation, gravity separation, etc to remove impurities and increase the grade.
- Converting difficult to leach minerals into a more easily leached mineral. Sulfides can be roasted to form oxides, sulfates or chlorides and carbonates can be converted to oxides by calcination.