棉秆沼气发酵生物预处理及接种物的驯化

Biological Pretreatment of Cotton Stalks and Domestication of Inocula in Biogas Fermentation

摘要:

通过多代淘汰的方法, 筛选了一组稳定高效的棉秆降解复合菌系-MEG复合菌系。将该菌系接入棉秆, 静置处理7 d后进行沼气发酵, 其产气量较未经预处理的提高了25%。变性梯度凝胶电泳(DGGE)分析结果表明, 生物预处理后棉秆沼气发酵系统的细菌群落结构多样性较未经预处理的丰富。同时, 比较了采用6种驯化方法获得的接种物对棉秆沼气发酵日产气量和累积产气量的影响, 结果表明, 采用河底泥、臭水沟泥、工厂废水底泥、荷塘底泥、湖底泥等5种污泥混合后驯化的活性污泥可作为棉秆沼气发酵的有效接种物, 其沼气发酵的日产气量和累积产气量均较单种污泥驯化的接种物高。

Abstract:

A composite microbial system MEG with high efficient and stable degradation of cotton stalks was screened through the method of multigeneration selection. This microbial system was inoculated to the cotton stalks, and then stationarily treated for 7 days. Afterwards, biogas fermentation was conducted. Compared to the condition of non-pretreatment, the gas production increased by 25%. DGGE analysis showed that the diversity of bacterial community structure in the biogas fermentation system of cotton stalks was more abundant compared to the condition of non-pretreatment. At the same time, comparison in the effects of inocula obtained from 6 kinds of domestication methods on daily and cumulative of biogas production of cotton stalks was conducted. The results showed that the inocula domesticated from the mixture of 5 kinds of activated sludge from river bed mud, sewage ditch, industrial wastewater bed, pond bed, and lake bed could be acted as effective inocula for biogas fermentation of cotton stalks. The daily gas production and cumulative gas production were higher compared to the inocula domesticated from one kind of activated sludge.