底物类型对产甲烷效能及微生物群落结构的影响

Impact of organic matter type on the efficiency and microbial community structure of an anaerobic digestion process

摘要:

为考察底物类型对厌氧消化过程的影响，以升流式厌氧膨胀床作为厌氧消化反应器，以经过"热-酶联合预水解"后的啤酒糟和猪粪作为处理对象，研究不同有机负荷率条件下反应器的运行效能和微生物群落结构.结果表明，当有机底物类型从啤酒糟转变为猪粪后，反应器的COD去除率降低40%，甲烷产量减少75%，有机物甲烷化率降低25%，且出水乙酸质量浓度由50 mg/L跃升至3 700 mg/L.同时，Firmicutes细菌门的丰度提高约1倍，Bacteroidetes细菌门的相对丰度则减少约50%；产甲烷菌数量减少61%，产甲烷菌属Methanobacterium替代Methanosaeta成为最占优势的古细菌菌属.

Abstract:

In order to investigate the impact of organic matter type on the efficiency and microbial community structure during anaerobic digestion operation, an expanded granular sludge bed (EGSB) was applied to treat brewery spent grain hydrolysates (BSGH) and pig manure hydrolysates (PMH) that were pre-hydrolyzed by specific enzymes under thermophilic conditions. Results showed that after the organic matter of BSGH was altered by PMH, a series decrease of 40%, 75% and 25% was observed for the bulk COD removal, methane production and organic biomethanation rate, respectively. Meanwhile, the acetic acid concentration in the effluent increased from 50 mg/L to 3 700 mg/L. For the microbial community, the abundance of Firmicutes doubled after the substrate type changing, while Bacteroidetes decreased 50% instead. The quantity of methanogens dropped by 61% and the previously most abundant genus Methanosaeta was replaced by Methanobacterium.