Effects of heavy metals on the performance of anaerobic sulfidogenic reactor using rape straw as carbon source

Effects of Zn2+, Cu2+ and Cd2+ in the synthetic acid mine drainage on the performance of the anaerobic sulfidogenic reactor using rape straw as carbon source were explored. Two different cases were respectively observed for the different metal dosages: stimulatory at lower concentrations and toxic/inhibitory at higher concentrations. Cellulose and hemicellulose were the major components hydrolyzed in the rape straw. Analysis of the heavy metals distribution in the anaerobic digested solid residue showed that adsorption and precipitation were the major mechanisms for the removal of heavy metals. This was also confirmed by the results of scanning electron microscopy and energy-dispersive spectrometry analysis.