Bioleaching
also known as biohydrometallurgy · bacterial leaching
Bioleaching uses iron- and sulfur-oxidising bacteria to regenerate ferric iron and sulfuric acid, which in turn oxidise and dissolve sulfide minerals. It operates at ambient temperature and pressure, so it suits low-grade ores and concentrates where smelting is uneconomic. Rates are far slower than chemical leaching, so residence times are measured in days rather than hours.
Why it matters in practice
Its economics rest entirely on being cheap rather than fast, which means agitation, aeration and temperature control become the dominant costs. Because the bacteria are living systems, bioleaching reactors behave more like bioprocess plant than like chemical reactors.
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Equipment referenced in this entry
Related terms
Reference entry GL-BIOLEACHING. Definitions on this page describe engineering practice in hydrometallurgical process design; they are not a substitute for test work on your own material.