铵影响嗜热厌氧反应器污泥丙酸互营氧化产甲烷过程的机理

项目名称： 铵影响嗜热厌氧反应器污泥丙酸互营氧化产甲烷过程的机理

项目编号： No.41501251

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 地质学

项目作者： 张琛

作者单位： 中国科学院过程工程研究所

项目金额： 20万元

中文摘要： 我国畜禽粪便对土壤和水体环境的污染日趋严重，厌氧消化技术是消除畜禽粪便污染的有效手段。然而，畜禽粪便的厌氧降解容易导致毒性化合物铵的积累，且高温会强化铵的毒性，最终导致厌氧消化过程的停滞。研究发现，铵对丙酸互营氧化产甲烷过程的抑制是厌氧消化停滞的主要原因。但是，目前对参与丙酸互营氧化产甲烷过程的关键微生物及铵影响丙酸互营氧化产甲烷过程的机理并不清楚。基于上述科学问题，本项目设计两部分试验：首先，将采用RNA稳定同位素探针技术结合高通量测序技术，探测嗜热厌氧生物反应器污泥中，参与丙酸互营氧化产甲烷过程的关键互营细菌和产甲烷古菌；其次，采用系列理化分析和基于细菌和古菌16S rRNA基因的克隆、T-RFLP、定量PCR分析和高通量测序等技术，阐明铵对丙酸互营氧化产甲烷过程及相应丙酸互营菌和产甲烷古菌的影响。最终，揭示铵影响嗜热厌氧反应器污泥丙酸互营氧化产甲烷的机理。

中文关键词： 微生物群落结构；铵；嗜热厌氧反应器污泥；丙酸互营氧化；甲烷

英文摘要： The anaerobic digestion has been successfully applied in treating the livestock and poultry manure to control the increasing pollution of soil and water environment in China. But, accumulation of ammonium, produced from the degradation of protein-rich materials, is one such detrimental factor in the anaerobic digesters used to treat waste such as livestock and poultry manure. High ammonium concentration would influence the performance of anaerobic digesters, such as the propionate accumulation and inhibition of methane production, and could cause the reactor upset or failure. However, the key microbes involved in syntrophic oxidation of propionate and methanogenesis in thermophilic anaerobic bioreactor sludge, and the mechanisms of ammonium effects on the process have remained poorly understood. In the present study, we collected sludge samples from full-scale manure digester and designed two laboratory microcosm experiments. First, RNA stable isotope probing (RNA-SIP) combined pyrosequencing technologies were used to detect the key microbes involved in syntrophic oxidation of propionate and methanogenesis in thermophilic anaerobic digester sludge. Then, the response of syntrophic propionate oxidizing methanogenesis and microbial populations to ammonium addition were determined by analyzing the rate of propionate degradation, the copy number and transcripts of bacterial and archaeal 16S rRNA gene in the sludge incubations. Finally, the mechanisms of ammonium effects on syntrophic oxidation of propionate and methanogenesis in thermophic anaerobic digester sludge would be clarified.

英文关键词： microbial community structure;ammonium;thermophilic anaerobic digester sludge;syntrophic propionate oxidation;methane