pH对高温厌氧耗氢产甲烷及微生物群落的影响  

Effect of pH on hydrogenotrophic methanogenesis and microbial community under thermophilic condition

作　　者：陈露蕊 杜诗云 谢丽[1] CHEN Lurui;DU Shiyun;XIE Li(The Yangtze River Water Environment Key Laboratory of the Ministry of Education,College of Environmental Science andEngineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学环境科学与工程学院长江水环境教育部重点实验室

出　　处：《化工进展》2019年第8期3816-3822,共7页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(51678424);上海市国际合作项目

摘　　要：随着化石燃料的枯竭,以厌氧耗氢产甲烷菌为功能优势菌群的异位(或离位)加氢沼气生物提纯工艺备受关注。本文考察了高温条件下不同初始pH对厌氧耗氢产甲烷过程及微生物群落的影响。研究结果表明,半连续流反应器中不同初始pH变化对产甲烷量影响不大,在以H2/CO2为基质的厌氧体系中,厌氧耗氢产甲烷过程是甲烷产生的主要途径。比产甲烷活性研究结果进一步表明碱性条件(初始pH=8.5~9.0)耗氢产甲烷污泥对氢气消耗率提高,产甲烷迟滞期缩短至6.9h,且甲烷产率高达19.8mL CH4/(gVS?h)。通过高通量测序技术对不同初始pH条件下的产甲烷古菌群落进行分析,3个样本均以厌氧耗氢产甲烷菌为主导,酸性和中性条件古菌群落属水平上相似,以Methanothermobacter为主,其相对丰度分别为90.6%、91.6%;而碱性条件下以Methanobacterium为主,其相对丰度可达83.6%,还发现了Methanomassiliicoccus,其相对丰度可达7.7%。碱性条件下Methanobacterium相对丰度的提高和Methanomassiliicoccus的富集,可能是碱性条件下比产甲烷活性提高的主要原因。Ex-situbiogas upgrading based on hydrogenotrophic methanogenic process has attractedmuch attention with the depletion of fossil fuels. This study investigated effects of initial p H on anaerobichydrogen-consuming methanogenesis and microbial community at 55 oC. Experimental results showed thatvariations of initial pH did not influence methane production under semi-continuous condition.Hydrogenotrophic methanogenesis was found to be the main pathway of methanogenesis under the testedconditions at the anaerobic system with H2/CO2 as the matrix. Alkaline condition(pH 8.5-9.0) improvedthe hydrogen consumption, and decreased lag phase of methane production to 6.9 h, and methane yieldwas as high as 19.8 mL CH4/(gVS?h). High throughput sequencing results further demonstrated thathydrogenotrophic methanogens was the main species. Methanothermobacter, with relative abundance of90.6%―91.6% was found to dominate under acidic and neutral conditions. While Methanobacterium withrelative abundance of 83% was the main species under alkaline condition. Methanomassiliicoccus was alsodetected, with relative abundance of 7.7%. The relative abundance of Methanobacterium and theenrichment of Methanomassicicoccus might be contributable to the high specific methane activity underalkaline condition.

关 键 词：耗氢产甲烷 高温 PH 比产甲烷活性 微生物群落 

分 类 号：X701.7[环境科学与工程—环境工程]