Biological Sulfate reduction using – hydrogen and methanol as energy and carbon sources for treating acid mine drainage

Acid-mine drainage (AMD) contains high concentrations of heavy metals these contaminants were generally avoided by lime neutralization. However, this method is expensive and generates large amounts of residual sludge. The selective precipitation of metals using H2S produced biologically by sulfate reducing bacteria has been proposed as an alternative process. in this study, acid mine drainage was treated in a laboratory scale. Bioreactor fed with an H2 and Methanol was used to treat acid mine drainage. The maximum rate of H2 transfer suggests that this step should not be a limiting factor. However, increase H2 flow rate increased the sulfate reduction rate. The replacement of synthetic medium by real effluent had increased sulfate reduction rate about30%. The maximum sulfate reduction rate observed with the real effluent was 0,009 (mmol/L h), corresponding to a residence time of 4.7 day.