Biological Reduction of COD and Sulphate by SRB in Anaerobic Moving Bed Biofilm Reactor under High Metal Loading Conditions

Abstract

The performance of an anaerobic moving bed biofilm reactor (MBBR) containing AnoxKaldnes K5 model for the treatment of raw acid mine drainage (AMD) was investigated for the reduction of sulphate and chemical oxygen demand using a consortium of sulphate reducing bacteria (SRB) dominated by Proteobacteria. The MBBR was enriched for 4 weeks, followed by introduction of raw AMD and sampling at intervals for 7 weeks. Maximum removal efficiency of COD was 99 % followed by 75 % sulphate reduction. The results showed that the bio-carrier is more suited for the COD reduction. Keywords— Acid mine drainage; Chemical oxygen demand; Heavy metals; moving bed biofilm reactor; Sulphate reducing bacteria.