厨余垃圾厌氧发酵失稳调控及微生物群落分析

针对厨余垃圾厌氧发酵过程中容易积累丙酸和丁酸导致反应体系酸化失稳的问题,驯化了富集耐丙酸和耐丁酸厌氧发酵菌群的接种菌泥,探究利用其对厨余垃圾干式厌氧发酵酸化失稳体系进行调控后对甲烷产量和微生物群落的影响.酸化失稳厌氧体系中添加耐丙酸菌泥调控后,与空白对照组相比反应体系中丙酸浓度削减6900.81mg/L,累积甲烷产量提升了259%;添加耐丁酸菌泥调控后,反应体系中丁酸浓度削减5371.56mg/L,累积甲烷产量提高了210%.微生物多样性分析表明,利用耐丙酸和耐丁酸菌群调控后,细菌种群丰富度明显提高.细菌属水平分析表明,投加耐丙酸驯化菌群后有利于Sporanaerobacter和Proteiniphilum等挥发性脂肪酸降解菌相对丰度增加;投加耐丁酸驯化菌群后,与乙酸型产甲烷菌有协同作用的Sporanaerobacter相对丰度有所增长.古菌属水平分析表明耐丙酸和丁酸菌调控后,氢型产甲烷菌Methanobacterium和乙酸型产甲烷菌Methanosaeta的相对丰度明显提高.

Regulation of acidified dry anaerobic digestion of kitchen waste and microbial community analysis

Aiming at the problems caused by the accumulation of propionic acid and butyric acid during anaerobic digestion, the sludge with propionic acid and butyric acid tolerant microorganism were domesticated, and they were added into the acidified systems of dry anaerobic digestion of kitchen waste to explore the effects on methane production and microbial communities. After treated by the sludge with propionic acid and butyric acid tolerant bacteria, the propionic acid concentration reduced by 6900.81mg/L, and the cumulative methane production increased by 259%, while the butyric acid concentration reduced by 5371.56mg/L, and the cumulative methane production increased by 210%, respectively. The richness of bacteria in the acidified systems was significantly improved after the regulation with propionic acid and butyric acid tolerant bacteria. The analysis of microbial community structure at genus level showed that the relative abundance of Sporanaerobacter and Proteiniphilum, having the ability of degrading volatile fatty acids, began to increase in the reactors treated by the sludge with propionic acid tolerant bacteria. After adding the sludge with butyric acid tolerant bacteria, the relative abundance of Sporanaerobacter increased. Sporanaerobacter have a synergistic effect with acetic acid methanogens. According to the analysis of archaea, the relative abundance of hydro methanogens and acetic acid methanogens increased in the groups treated with propionic acid and butyric acid tolerant bacteria, respectively.