厌氧消化过程稳定性与微生物群落的相关性  

Investigation on the relationship between process stability and microbial community in anaerobic digestion

作　　者：李蕾[1] 何琴[1] 马垚[1] 赵小飞[1] 瞿莉[1] 王小铭[1] 彭绪亚[1] LI Lei;HE Qin;MA Yao;ZHAO Xiao-fei;QU Li;WANG Xiao-ming;PENG Xu-ya(Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China)

机构地区：[1]重庆大学三峡库区生态环境教育部重点实验室,重庆400045

出　　处：《中国环境科学》2016年第11期3397-3404,共8页China Environmental Science

基　　金：国家"十一五"科技支撑计划(2010BAC67B01)

摘　　要：为探析厌氧消化过程稳定性与微生物群落的相关性,在餐厨垃圾厌氧消化反应器中引入负荷扰动以诱导不同的运行状态,理化分析和高通量测序相结合用于研究各个状态下的状态参数响应及微生物群落动态.结果表明,均衡的群落结构保证了反应器的稳定运行,稳定状态下反应器的甲烷产率和挥发性固体(VS)去除率分别高达(0.50±0.01)LCH_4/g VS和(89.58±0.08)%.高负荷下产酸细菌(柔膜菌门、放线菌门)大量增殖,诱导互养脂肪酸降解菌(梭菌纲)的相对丰度剧增,然而与之互营的氢型产甲烷菌的丰度和活性却下降了.产甲烷菌与互养脂肪酸降解菌的失衡导致它们不能有效的互养合作,从而引起挥发性脂肪酸(VFA)积累和过程失稳.积累的VFA和氨使比乙酸产甲烷活性(SAMA)和比产甲烷活性(SMA)分别下降60.12%和72.51%,进一步加剧了过程失稳.扰动停止后,尽管反应器恢复了原有运行条件和性能,但微生物群落达到了新的平衡.To explore the relationship between process stability and microbial community in anaerobic digestion, organicloading rate (OLR) disturbances were introduced into an anaerobic digester treating food waste (FW) to induce differentprocess stages. Physico-chemical analysis along with the 454-pyrosequencing microbial technique were performed tomonitor the responses of state parameters as well as the dynamics of microbial community. Results showed that balancedcommunity structure ensured the stable operation of the digester. Under steady-state conditions, the methane yield reached(0.50±0.01) LCH4/gVS and volatile solids (VS) removal rate reached (89.58±0.08) %. Under high OLR conditions, therelative abundance of acid-producing bacteria (phyla Tenericutes and Actinobacteria) increased dramatically, whichinduced the proliferation of syntrophic fatty acid degrading bacteria (class Clostridia), while the abundance and activity ofsyntrophic hydrogenotrophic methanogens decreased. The imbalance relationship between methanogens and syntrophicfatty acid degrading bacteria caused their inefficient syntrophy, eventually resulting in volatile fatty acid (VFA)accumulation and process deterioration. Moreover, the accumulated VFA and ammonia reduced the specific acetoclasticmethanogenic activity (SAMA) and specific methanogenic activity (SMA) by 60.12% and 72.51%, respectively, whichfurther deteriorated the digestion process. Although the digester afterwards recovered to its original operational conditionsand process performance, the microbial community profile changed and achieved new steady-state conditions.

关 键 词：餐厨垃圾 厌氧消化 过程稳定性 微生物群落 454高通量测序 

分 类 号：X705[环境科学与工程—环境工程]