低温下复合菌剂对餐厨垃圾厌氧消化的影响

Effects of compound microbial agents on anaerobic treatment of food waste at low temperature

为提高低温环境下厌氧反应器处理餐厨垃圾的效能,分别向升流式厌氧污泥床(UASB)反应器中加入不同体积的复合菌剂(0,1,2,5mL),对厌氧消化过程中COD与NH_(3)-N去除率、关键酶活性、微生物群落结构及功能等进行分析.结果表明,加入2mL复合菌剂的UASB反应器可获得最佳的COD(42.47%)及NH_(3)-N(63.93%)去除率;同时厌氧污泥乙酸激酶(AK)和辅酶F_(420)的相对活性与空白对照组相比分别升高了(120.39±4.14)%和(148.63±4.32)%.且加入2mL复合菌剂的UASB反应器中微生物丰度和多样性达到最高;Proteobacteria(15.30%)与Thermotogae(1.13%)的相对丰度最高,这对有机酸生产以及维持厌氧消化过程的稳定起到重要作用;此外,相比于对照组中的优势古菌Methanobacterium(30.51%)和Methanothrix(32.80%),加入2mL复合菌剂降低了Methanobacterium(18.93%)的相对丰度,提高了Methanothrix(34.32%)的相对丰度,这有利于乙酸型产甲烷过程的进行.

In order to improve the efficiency of the anaerobic reactor in the low temperature environment,different volumes of compound microbial agents(0,1,2,5mL)were added to the upflow anaerobic sludge bed(UASB)reactor,and the removal rates of COD and NH_(3)-N,key enzyme activities,microbial community structure and function during the anaerobic digestion process were analyzed.The results showed that the optimum removal rates of COD(42.47%)and NH_(3)-N(63.93%)were obtained in the UASB reactor with 2mL of compound microbial agents.And the relative activities of acetate kinase(AK)and coenzyme F_(420) in anaerobic sludge were increased by(120.39±4.14)%and(148.63±4.32)%compared with the control group.In addition,the abundance and diversity of microorganisms reached the highest,and the relative abundance of Proteobacteria(15.30%)and Thermotogae(1.13%)were the highest,which played an important role in organic acid production and maintaining the stability of anaerobic digestion process.Meanwhile,compared with the dominant archaea Methanobacterium(30.51%)and Methanothrix(32.80%)in the control group,the relative abundance of Methanobacterium(18.93%)was decreased by adding 2mL compound microbial agents.The relative abundance of Methanothrix(34.32%)was increased,which was favorable for the acetic acid type methanogenesis process.