Reductive Dechlorination of PCB-Contaminated Sediments in an Anaerobic Bioreactor System

摘要

An anaerobic bioreactor system was operated in a batch recycle mode to establish the microbial biodegradation of Aroclor 1248-spiked sediment, utilizing sanitary landfill leachate as a novel carbon, nutrient, and/or microbial source. Experiments conducted on two bioreactors confirmed that significant dechlorination of Aroclor 1248-spiked sediments occurred. After 13 weeks of operation, the average total chlorine/biphenyl of the original Aroclor was reduced by 11% and 23%, with the majority of dechlorination occurring within 7 weeks. No dechlorination was observed in the sterilized control reactor. The overall significance is the first reported occurrence of anaerobic dechlorination of a PCB-contaminated sediment in a low-cost laboratory-scale bioreactor system. The environmental significance is the reduction in chlorine content of the original Aroclor, an important component in any environmental bioremediation program. Innovative approaches to laboratory-scale bioreactor monitoring and bioreactor design principles applicable to hazardous waste containment areas are also discussed.