不同碳氮比对干法厌氧消化产沼气特性及细菌群落多样性的影响

为研究不同初始C/N值的混合物料对甘蔗叶干法厌氧消化过程中理化参数以及产沼气特性的影响及产气最佳的C/N值厌氧消化过程中细菌群落结构多样性，研究采用牛粪与甘蔗叶以及啤酒厂滤泥这3种有机固废物混合并加入自行研究设计的发酵罐里进行厌氧消化，并采用Nested-PCR（巢式PCR）技术扩增消化过程中细菌的16S rDNA V3区域，并通过DGGE方法分析初始C/N值为15.02厌氧消化过程细菌群落的多样性。实验结果表明，初始C/N值为15.02的混合物料产甲烷最佳，最高累计产气量为1 748.63 mL·kg-1，甲烷最高含量为59.26%，最高日产甲烷量为13.58 mL·kg-1；通过研究最佳C/N值为15.02的细菌多样性，可知在厌氧消化过程中细菌数量和群落结构丰富多样，样品间的细菌群落结构差异性相对较大，样品间存在与产沼气相关的共有的优势细菌。

Effects of different C/N ratios on biogas production and microbial community in dry anaerobic digestion

To investigate effects of different initial C/N ratios on physico-chemical parameters including characteristics of biogas production and to investigate the influence of the optimized C/N ratio on microbial community diversity during dry anaerobic digestion of cattle manure,sugarcane leaves,and filter mud from a beer factory,experiments were conducted using self-designed anaerobic fermentation equipment.To analyze changes in microbial community composition due to optimized C/N ratios of the anaerobic digestion process by using PCR-denaturing gradient gel electrophoresis (DGGE),the bacterial V3 domain sequences of the 16S rDNA region were amplified by nested PCR.The results showed that with an optimized initial C/N ratio of 15.02,the maximal yield of biogas production was 1 748.63 mL·kg-1,the highest methane concentration was 59.26%,and the highest daily amount of methane produced was 13.58 mL·kg-1.Analysis of community dynamics indicated that bacterial abundance was rich and community structure varied during process of anaerobic digestion;a dominant species associated with biogas production was common identified between samples.