Treatment of Acid Red A Wastewater in an Electrolytic Bioreactor
电解-生物耦合技术处理酸性红A染料废水

An electrolytic bioreactor was devised to treat the wastewater containing Acid Red A (AR-A, 74 mg/L), and the effects of current density, anode materials, methanol concentration and chloride concentration were investigated. The results showed that AR-A could be simultaneously removed by electrochemical oxidization and microbial degradation with methanol as a co-substrate. When a current of 300 mA was applied across the electrolytic bioreactor and the influent CODCr was 740 mg/L, the removal of AR-A and CODCr was 79% and 84%, higher than those without DC current application (59% and 74%, respectively). The amounts of the AR-A and CODCr biodegraded by bacteria increased with the increase in the methanol concentration, due to the increase in the biodegradation rate and better tolerance of the bacteria in the biofilm to the electric field. The increase in chloride concentration and current density increased the observed AR-A removal rate, despite of the inhibition of the metabolism of bacteria in the biofilm by the hypochlorite ions produced from chloride by anodic oxidation. Fe anode was more efficient in treatment of the wastewater of AR-A compared with the graphite anode. However, more sediments were produced in the reactor.