产乙酸耦合系统产酸及其微生物种群动态分析

Operation of acidogenesis and homoacetogenesis coupling system and its microbial community analysis

研究了产氢产酸／同型产乙酸耦合系统在不同底物负荷条件下运行的产酸效率及其不同运行阶段的微生物种群变化．结果表明，系统在底物负荷为4～6g／（L．d）、水力停留时间（HRT）为20d的状态下稳定运行时，乙酸在产氢产酸相达到25-32g／L；在同型产乙酸相达到14g／L左右；系统乙酸产率为0．40～0．48g／g．底物负荷不同时，微生物多样性发生相应变化．同型产乙酸相的Shannon指数远低于产氢产酸相．耦合系统两相中始终有Clostridium和Fusobacterium的存在，而且为优势种群．

To investigate the operation stability of the acidification and homoacetogenesis coupling system and the microbial population dynamics under acidification condition, semi-continuous long term run was conducted and terminal restriction fragment length polymorphism （T-RFLP） technique was used to analyze the dynamics change of microbial population dynamics. When substrate loading rate is 4-6g/（L-d） and HRT is 20 d, acetate in the acidogenesis phase can reach 25-32g/L and in homoacetogenesis it can be 14g/L. The acetate yield in the coupling system is 0.40-0.48g/g. As for the microbial community, the Shannon-Weiner index in the homoacetogenesis phase is much lower than that in the acidogenesis phase. There are Clostridium and Fusobacterium in two phases of the coupling system all the time, and they are the dominant populations.