Dynamics of microbial community in a mesophilic anaerobic digester treating food waste: relationship between community structure and process stability
Anaerobic digestion (AD) is a promising process for organic waste treatment to achieve both the waste reduction and energy generation.However, despite a continuously increasing interest and popularity on AD, the process instability under high organic loading rate (OLR) is a concern.Microorganisms are the core of the anaerobic digesters;the understanding of the microbial community is crucial for improving efficiency and process stability of anaerobic digesters.To investigate the linkage between process stability and microbial community, and describe the microbial mechanisms of system instability, the study introduced OLR disturbances into a mesophilic anaerobic digester treating food waste (FW) to induce stable and deteriorative phases, during which physicochemical analysis along with the pyrosequencing microbial technique were performed to monitor process parameters and microbial population of each phase, respectively.Results show that the relative abundance of acid-producing bacteria and syntrophic volatile fatty acid (VFA) oxidizers increased dramatically at deteriorative phase, while the dominant methanogens did not shift from acetoclastic to hydrogenotrophic groups.The mismatching between bacteria and methanogens may partially be responsible for the process deterioration.Moreover, the succession of predominant hydrogenotrophic methanogens reduced the consumption efficiency of hydrogen;meanwhile, the dominant Methanosaeta with low acetate degradation rate, and the increase of inhibitors concentrations further decreased its activity, which may be the other causes for the process failure.These results improve the understanding of the microbial mechanisms of process instability, and provide theoretical basis for the efficient and stable operation of anaerobic digester treating FW.
Anaerobic digestion Food waste Microbial community Process stability Pyrosequencing
Lei Li Qin He Yao Ma Xiaoming Wang Xuya Peng
Key Laboratory of Three Gorges Reservoir Region”s Eco-Environment,Ministry of Education,Chongqing University,Chongqing,China No.174,Shapingba Zhengjie Street,Chongqing,400045,China
国内会议
广州
英文
387-399
2015-05-01（万方平台首次上网日期，不代表论文的发表时间）