Cao Zhi-Ping, Wu Jing, Zuo Jian-E, Wang Xiao-Lu, Wang Chong, Wang Guang-Qi, Wang Kai-Jun, Qian Yi
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
China Northwest Architecture Design and Research Institute Co., Ltd., Xi'an 710018, China.
Huan Jing Ke Xue. 2017 May 8;38(5):2059-2064. doi: 10.13227/j.hjkx.201611057.
High-solid anaerobic digestion (HSAD) of sludge has several advantages like smaller reactor, lower energy consumption and less digestate. However, the understanding about the mechanism especially the microbial mechanism is still limited. In this study, microbial communities of a pilot-scale sludge HSAD system at steady state were investigated with 16S rRNA clone library technology. The system employed an enhanced two-phase anaerobic digestion process, i. e. 'hyperthermophilic acidogenesis (70℃, 3 d)-thermophilic methanogenesis (55℃, 12.5 d)' to treat waste activated sludge with a solid content of about 9%. The volatile solid (VS) removal rate was 35.7% and methane yield (CH/VS) was 0.648 m·kg. The bacterial compositions of the two phases were significantly different:there were plenty of proteolytic bacteria in hyperthermophilic acidogenesis phase; and the bacteria degrading polysaccharides like cellulose and the bacteria utilizing long-chain fatty acids were found in thermophilic methanogenesis phase; some bacteria degrading simple saccharides existed in both phases. In both phases, the dominant archaea were . Especially, 100% of the retrieved archaea in the thermophilic methanogenesis phase belonged to genus . This indicated that hydrogenotrophic methanogenesis was the predominant methanogenesis pathway in this system since methane was only detected in the methanogenesis phase.
污泥的高固体厌氧消化（HSAD）具有几个优点，如反应器较小、能耗较低和消化产物较少。然而，对其机制尤其是微生物机制的了解仍然有限。在本研究中，采用16S rRNA克隆文库技术对中试规模污泥HSAD系统在稳定状态下的微生物群落进行了研究。该系统采用强化两相厌氧消化工艺，即“超嗜热产酸（70℃，3天）-嗜热产甲烷（55℃，12.5天）”来处理固体含量约为9%的废弃活性污泥。挥发性固体（VS）去除率为35.7%，甲烷产量（CH/VS）为0.648 m³·kg⁻¹。两相的细菌组成有显著差异：超嗜热产酸阶段有大量蛋白水解细菌；嗜热产甲烷阶段发现了降解多糖（如纤维素）的细菌和利用长链脂肪酸的细菌；两个阶段均存在一些降解单糖的细菌。在两个阶段，优势古菌均为 。特别是，嗜热产甲烷阶段检索到的古菌100%属于 属。这表明在该系统中，氢营养型产甲烷是主要的产甲烷途径，因为仅在产甲烷阶段检测到甲烷。
