摘要
In this paper, the inhibition of methanogens by phenol in coal gasification wastewater（CGW）was investigated by both anaerobic toxicity tests and a lab-scale anaerobic biofilter reactor（AF）. The anaerobic toxicity tests indicated that keeping the phenol concentration in the influent under 280 mg/L could maintain the methanogenic activity. In the AF treating CGW,the result showed that adding glucose solution as co-substrate could be beneficial for the quick start-up of the reactor. The effluent chemical oxygen demand（COD） and total phenol reached1200 and 100 mg/L, respectively, and the methane production rate was 175 m L CH4/g COD/day.However, if the concentration of phenol was increased, the inhibition of anaerobic micro-organisms was irreversible. The threshold of total phenol for AF operation was 200–250 mg/L. The extracellular polymeric substances（EPS） and particle size distribution of anaerobic granular sludge in the different stages were also examined, and the results indicated that the influence of toxicity in the system was more serious than its effect on flocculation of EPS. Moreover, the proportion of small size anaerobic granular sludge gradually increased from10.2% to 34.6%. The results of high through-put sequencing indicated that the abundance of the Chloroflexi and Planctomycetes was inhibited by the toxicity of the CGW, and some shifts in the microbial community were observed at different stages.
In this paper, the inhibition of methanogens by phenol in coal gasification wastewater（CGW）was investigated by both anaerobic toxicity tests and a lab-scale anaerobic biofilter reactor（AF）. The anaerobic toxicity tests indicated that keeping the phenol concentration in the influent under 280 mg/L could maintain the methanogenic activity. In the AF treating CGW,the result showed that adding glucose solution as co-substrate could be beneficial for the quick start-up of the reactor. The effluent chemical oxygen demand（COD） and total phenol reached1200 and 100 mg/L, respectively, and the methane production rate was 175 m L CH4/g COD/day.However, if the concentration of phenol was increased, the inhibition of anaerobic micro-organisms was irreversible. The threshold of total phenol for AF operation was 200–250 mg/L. The extracellular polymeric substances（EPS） and particle size distribution of anaerobic granular sludge in the different stages were also examined, and the results indicated that the influence of toxicity in the system was more serious than its effect on flocculation of EPS. Moreover, the proportion of small size anaerobic granular sludge gradually increased from10.2% to 34.6%. The results of high through-put sequencing indicated that the abundance of the Chloroflexi and Planctomycetes was inhibited by the toxicity of the CGW, and some shifts in the microbial community were observed at different stages.
基金
financially supported by the Talented Young Scientist Program supported by the Ministry of Science and Technology,P.R.China as an Assistant Researcher(IND-15-003)at the School of Environmental Science and Engineering,Shanghai Jiao Tong University,China
