Review of sulfate reduction based bioprocesses for acid mine drainage treatment and metals recovery

Abstract

Biological sulfate reduction is attracting increasing interest in the mining industry. Sulfate reducing bacteria (SRB) can be used for treating acid mine drainage (AMD) and for recovering metals from mine waters. Biologically produced hydrogen sulfide precipitates metals as low solubility metal sulfides, while biogenic bicarbonate alkalinity neutralizes acidity. This paper reviews various passive and active SRB-based processes, bioreactor process configurations and alternative substrates for SRB. The cost of biological treatment depends on location, engineering design, the characteristics of the mine drainage, the substrate, profit obtained from metals recovered and the effluent discharge criteria.