ANAEROBIC DEGRADATION OF PENTACHLOROPHENOL (PCP) IN BIOLOGICAL EXPANDED-BED REACTOR

In this study, anaerobic degradation of PCP was discussed in an expand ed-bed GAC anaerobic reactor which was applied to treatment of wastewa ter containing high concentration of PCP-Na as well as acetate. Total- COD concentration in effluent was kept less than 100 mg/L except for t he start-up duration and PCP-Na concentration was kept less than 0.50 mg/L under the experimental conditions (HRT of 5 days, influent PCP-Na concentration of 100 and 400 mg/L, and influent Total-GOD concentrati on of 480 and 1600 mg/L). It was indicated by methane production rate and material balance of PCP-Na that about 60% of PCP-Na loaded into th e reactor was transformed to methane and CO2 for 375 days. GC/MS analy sis of extracts of the GAG medium and effluent indicated that reductiv e dechlorination of PCP occurred and dechlorinated phenols were adsorb ed on the GAC in the reactor. Microorganisms collected from the reacto r degraded PCP-Na and 2-GP anaerobically and addition of acetate in cu lture accelerated anaerobic degradation of PCP-Na in batch experiments . Copyright (C) 1996 IAWQ.