As near-surface oxide orebodies are depleted, mines are having to process deeper sulfide ores that are lower in metal grade and metallurgically more complex. Modern technologies that are simple, cost effective and environmentally sound are required for their extraction. In many cases, bioleaching is the most suitable process.

Tank Bioleaching Of Chalcopyrite Concentrate

One application to which agitated tank bioleaching has been found particularly suitable is the treatment of dirty concentrate produced from mixed copper and zinc ore (which is also contaminated with lead, silver and other metals). It is not possible to produce clean flotation concentrates of copper and zinc separately, due to the complex mineralogy of these types of ores – the one is always contaminated by the other, leading to significant losses and consequent smelter penalties. Such ores are found, for example, in parts of Mexico.