碳酸氢盐对嗜氢和嗜乙酸产甲烷菌的影响机制  

Mechanisms of bicarbonate's effect on hydrogenotrophic and aceticlastic methanogens

作　　者：张玉鹏[1] 李建政[1] 刘凤琴[1] 刘崇[1,2] 施恩[1] ZHANG Yu-peng;LI Jian-zheng;LIU Feng-qin;LIU Chong;SHI En(State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology, Harbin 150090, China;The 101 Research Institute of the Ministry of Civil Affairs,Beijing 100070, China)

机构地区：[1]哈尔滨工业大学,城市水资源与水环境国家重点实验室,黑龙江哈尔滨150090 [2]民政部一零一研究所,北京100070

出　　处：《中国环境科学》2017年第5期1937-1944,共8页China Environmental Science

基　　金：国家自然科学基金资助项目(51478141);城市水资源与水环境国家重点实验室(哈尔滨工业大学)自主课题(2016DX06)

摘　　要：分别以H_2/CO_2和乙酸盐为底物,研究了HCO_3~–浓度([HCO_3~–])对厌氧活性污泥中嗜氢产甲烷菌(HM)和嗜乙酸产甲烷菌(AM)活性的影响,并从群落结构、反应动力学和热力学等方面进行了分析.结果表明,0.05~0.20mol/L的[HCO_3~–]对HM的产甲烷活性具有刺激作用,刺激浓度随着系统氢分压的升高而降低.但高[HCO_3~–](0.05~0.20mol/L)对AM的产甲烷反应有抑制作用.HM中的Methanobacterium formicium和AM中的Methanosarcina mazei是厌氧活性污泥的优势菌群.随[HCO_3~–]的升高,M.formicicum的丰度逐渐增加,而M.mazei的丰度则呈现先增加([HCO_3~–]￡0.10mol/L)后降低([HCO_3~–]30.15mol/L)的趋势.[HCO_3~–]可显著改变发酵体系的p H值和产甲烷反应的吉布斯自由能变化,进而影响HM和AM的产甲烷效能.Effect of bicarbonate concentration([HCO3-])on hydrogenotrophic methanogens(HM)and aceticlastic methanogens(AM)in anaerobic activated sludge was investigated with H2/CO2and acetate as the sole carbon source,respectively.The mechanisms of bicarbonate's effect on methane formation was analysed based on the methane production efficiency,community structure of methanogens,reaction kinetics and thermodynamics.The results showedthat[HCO3-]ranged from0.05to0.20mol/L could stimulate the activity of HM,and the higher hydrogen partial pressure,the lower[HCO3-]for the stimulation.An increased[HCO3-],on the contrary,would inhibit the methanogenesis of AM.Methanobacterium formicium and Methanosarcina mazei were identified as the dominated HM and AM,respectively,in the incubated anaerobic active sludge.It was found that the abundance of M.formicicum was enhanced by the increased[HCO3-]in the fermentation systems.The abundance of M.mazei was also improved by a[HCO3-]less than0.10mol/L,but decreased with the[HCO3-]over than0.15mol/L.Variation of[HCO3-]could significantly change the pH and Gibbs free energy of the methanogenic reactions in the fermentation processes,and the methanogenesis activities of HM and AM were further affected as a result.

关 键 词：厌氧活性污泥 碳酸氢盐 产甲烷反应 嗜氢产甲烷菌 嗜乙酸产甲烷菌 

分 类 号：X172[环境科学与工程—环境科学]