The aims of this study are to enhance the pollutant removal
and methane production of AF in treating CGW, and to
understand the mechanism of toxicity of CGW toward anaerobic
bacteria. For this purpose, the strategy of reducing the
substrate concentration in influent was adopted to enhance AF
performance in treating CGW, including dilution and effluent
recirculation. The toxicity of CGW on anaerobic microorganisms
was analyzed, including the toxicity of CGWon anaerobic
activated sludge, activity recovery of the activated sludge
treated by CGW, and the adaptability of anaerobic sludge to
CGW by long-term domestication. Finally, the mechanism of
the enhanced performance of AFwith effluent recirculationwas
investigated by analyzing the shifts of microorganism and pollutant distributions in AF and the biodegradation characteristics
of substrates in CGW