Mining chemicals play a crucial role in the various stages of mining operations – including during the extraction and processing of minerals - and are utilised to improve efficiency, enhance mineral recovery, and ensure the overall safety and environmental sustainability of the mining process.
Some common types of mining chemical compounds and their uses include:
The separation of gangue minerals from those that are being mined can be a complex process, but one which is made easier by collectors. These chemicals enhance the attachment of hydrophobic particles (the valuable minerals) to air bubbles, allowing their separation from the water-loving gangue material which is both unwanted and worthless.
In mineral processing, the role of frothers is to produce a stable froth in the flotation stage from which minerals can be skimmed from the ore slurry. These chemicals, along with water and air bubbles enable the valuable mineral commodity to be separated more easily from other particles which are effectively waste products.
Depressant chemicals are used in conjunction with frothers to inhibit the flotation of specific minerals. This prevents their attachment to the air and water bubbles, aiding in the separation of unwanted minerals from valuable ones.
Dispersants are typically surfactants which are employed to prevent clumping of particles to improve the separation process.
5. SOLVENT EXTRACTANTS
Extractants are used in the purification of minerals from the leach solutions used during the extraction process.
6. GRINDING AIDS
Grinding aids can assist in increasing mineral production by as much as 25% and are especially useful for extraction from lower quality ore. Grinding aids reduce adhesion and cohesion through the grinding circuit improving efficiency, reducing energy consumption, and increasing throughput.
7. pH MODIFIERS
pH modifiers are used to adjust the acidity or alkalinity of the mineral processing system. Controlling pH levels is crucial for optimising the efficiency of various processes, including flotation and leaching.
Flocculants are used to promote the settling of solid particles in mining wastewater or tailings dams. They aid in the separation of suspended solids from water, facilitating water recycling and minimising environmental impact of run off from the mining process.
Although not technically classified as chemicals in the traditional sense, explosives are crucial for the fragmentation and excavation of rock in mining operations, enabling access to ore bodies.
Different chemicals are used at different stages of mining and which ones depends on the quality and type of ore being processed, and the minerals which are embedded within it which are being extracted.
It is incumbent on mining companies to comply with local regulations and best practices to ensure the responsible use and management of mining chemicals to minimise their impact on the environment.