make use of microbes, usually bacteria and archaea - bio
mainly take place in aqueous environment – hydro
deal with metal production and treatment of metal containing materials and solutions – metallurgy
"Biohydrometallurgy may be defined, in very general terms, as that branch of biotechnology dealing with the study and application of the economic potential of the interactions between the microbial world and the mineral kingdom. It concerns, thus, all those engaged, directly or indirectly, in the exploitation of mineral resources and in environmental protection: geologists, economic geologists, mining engineers, metallurgists, hydrometallurgists, chemists and chemical engineers. In addition to these specialists, there are the microbiologists whose work is indispensable in the design, implementation and running of biohydrometallurgical processes."
Biohydrometallurgy is used to perform processes involving metals, for example, microbial mining, oil recovery, bioleaching, water-treatment and others. Biohydrometallurgy is mainly used to recover certain metals from sulfide ores. It is usually utilized when conventional mining procedures are too expensive or ineffective in recovering a metal such as copper, gold, lead, nickel and zinc.