生物酶对初沉污泥厌氧发酵产短链脂肪酸的调控研究

旨在通过生物酶调节(碱性蛋白酶、中性蛋白酶和α-淀粉酶)提高初沉污泥的厌氧发酵效率,并通过微生物群落结构解析,SCFAs (short-chain fatty acids,SCFAs)组分分析等揭示其调控机理.结果表明,3种生物酶均可增强初沉污泥水解和产酸作用,碱性蛋白酶调控系统对初沉污泥厌氧发酵的促进效果最为明显,发酵第4d SCFAs的产量和产率分别达到1508mg COD/L和0.174g COD/g VSS.对比控制组,SCFAs的产量和产率分别增加了1129mg COD/L和0.13g COD/g VSS.微生物群落结构分析表明,在碱性蛋白酶调控发酵系统中,Lentimicrobium、Proteiniphilum和Bacteroides等发酵相关菌群的相对丰度得到了改善,Methanosaeta、Methanospirillum等产甲烷古菌的活性受到了抑制.同时,生物酶调控对促进发酵过程乙酸占比也有促进作用.

Study on regulating anaerobic fermentation for producing short-chain fatty acids from primary sludge in WWTPs by different bio-enzymes

The objective of this study was to estimate the efficiency of SCFA production from primary sludge using bio- enzyme regulation including alkaline protease, neutral protease and α-amylase. The regulation mechanism was revealed by microbial community and SCFAs component analyses. The three kinds of bio-enzymes could enhance the hydrolysis and acid production during the fermentation of primary sludge. Compared with the blank group, the production and yield of SCFAs achieved 1508 mg COD/L and 0.174 g COD/g VSS on the fourth day of fermentation, respectively, increasing by 1129 mg COD/L and 0.13 g COD/g VSS. Microbial community structure analysis showed that the relative abundance of fermentation-relating bacteria such as Lentimicrobium, Proteiniphilum and Bacteroides were improved, and the growth of methanogenic archaea such as Methanosaeta and Methanosapirillum was inhibited when bio-enzymes were added into the fermentation system. At the same time, the production of acetic acid in the regulated fermentation process was also found to promote.