Four Production Processes In The Mineral Beneficiation Processing Plant
Rock that can be processed at a profit is called ore. To extract the minerals carrying the valuable metal from the ore, a combination of separation operations, typically known as mineral processing or ore beneficiation is required. The objective of the mineral processing plant is to increase, in an economically viable manner, the concentration of valuable minerals so that the subsequent metal extraction process becomes profitable.
Rock fragmentation (comminution) liberates valuable minerals from the ore matrix (in mineral processing), thereby increasing the surface area for high reactivity (in hydrometallurgy) and facilitating the particle transport between unit operations.Comminution is carried out in crushers and grinding mills. Whereas crushers operate on dry ores, grinding mills mostly work on slurries, which means that a certain amount of water must be added to the ore before it enters the milling circuit.
It is the process of ore enrichment that gets rid of most of the useless species (gangue) keeping as much as possible of the valuable minerals (concentration process). Froth flotation is the most commonly used method for sulfide separations, whereas gravity separation is used for heavy minerals (such as precious metals, iron oxides, etc.), with magnetic and electrostatic separation for industrial minerals and iron oxides. In froth flotation, air bubbles are injected into an agitated pulp. By adjusting some pulp properties (pH, pulp potential (Eh), etc.) and/or using adequate reagents,This results in separation by transferring the valuable minerals to the air bubbles which form a froth floating on the surface of the pulp, from where it is removed as valuable product (concentrate).
Final product handling
It normally involves two steps:
1. Dewatering processes, by which the solid particles, either in the concentrate or the tailings streams, are concentrated by elimination of part of the contained water, which is recovered for re-use. This is normally done by using thickeners, although in some cases (concentrates) filters and driers might be necessary to further decrease the water content.
2. Material transport: concentrate is then transported as thicker pulp to the final handling facility for further transportation to the port or smelting facilities, whereas tails are dumped into ponds in an environmentally friendly manner.