Treatment of coal gasification wastewater with anaerobic filter technology

Coal gasification has been regarded as a promising technology for the production of the gaseous fuels needed to supplement dwindling reserves of petroleum and natural gas. The organic constituents of coal gasification wastewater are 60 to 80% phenols. The first-stage, berl-saddle-packed anaerobic filter resulted in very limited reductions in DOC, COD, and the specific organic compounds monitored. Excellent removal efficiencies of DOC, COD, and the specific organic compounds were realized in the completely mixed, expanded-bed anaerobic granular activated carbon filter. The activated carbon offers a larger sheltered microbial attachment area than does the berl-saddle plastic medium. The success of the activated carbon packed filter is probably due to surface adsorption. Some of the mass of the retained COD may represent the fraction of the feed constitutents that is nonbiodegradable in and inhibitory to the anaerobic environment. 11 figures, 4 tables. (DP)