Acid mine drainage treatment in fluidized-bed bioreactors by sulfate-reducing bacteria: A critical review

Acid mine drainage is an important environmental problem related to the release of acidic, sulfate-, and metal-containing wastewater into the environment. Sulfate-reducing bacteria can be used for treating mining wastewaters and recovering metals in several bioreactor configurations. The fluidized-bed configuration is an efficient way for acid mine drainage remediation due to the high biomass retention, the great resistance to inhibitors, and the possibility to use high organic, sulfate, and metal loading rates at low hydraulic retention times. Additional research is needed to assess the removal of the organic rest-pollution and the factors that promote a better metal recovery in single-stage processes.