One-step acquirement of superior microbial communities from mesophilic digested sludge to upgrade anaerobic digestion
One-step acquirement of superior microbial communities from mesophilic digested sludge to upgrade anaerobic digestion
复制标题
从中温消化污泥中一步获得优质微生物群落以升级厌氧消化
DOI：
10.1016/j.chemosphere.2020.128047
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发表时间：
2021
期刊：
影响因子：
8.8
通讯作者：
Lyu Yong-Kang
中科院分区：
文献类型：
--
作者：
Wu Li-Jie;Li Xiao-Xiao;Yang Fan;Zhou Quan;Ren Rui-Peng;Lyu Yong-Kang
厌氧消化是一种很有前景的废物能源替代技术。然而，有机固体废物的常规中温消化的效率升级始终是必不可少的。采用超嗜热或嗜热微生物群落是可行的升级替代方案之一。鉴于无法获得优质微生物群落，使用中温消化污泥作为接种物，并立即控制在 70 °C 和 55 °C 分别用于超嗜热和嗜热接种物的驯化。废活性污泥连续同步地送入两个消化池。经过一轮后，高温沼气池的沼气产量稳定在0.22 L L−1d−1，甲烷比例超过60%，而超高温沼气池则出现波动，大约需要三倍时间才能达到相对稳定的沼气产量0.12 L L−1d−1。然而，尽管沼气产量较低，但在超高温消化池中观察到较高的水解率 24.4%。因此，产甲烷步骤限制了超高温消化的整个厌氧过程，70°C 的消化适合作为增强水解的预发酵阶段。嗜热消化池中甲烷丝菌属的比例逐渐下降，而另一种乙酸分解菌属甲烷八叠球菌最终适应了占优势的产甲烷菌。除甲烷丝菌外，氢营养古菌在超高温消化池中也变得具有竞争力，其中甲烷嗜热菌占主导地位，占 22.6%。属于变形菌门的精神杆菌属在 70°C 下的存活率比其他细菌更好，最终比例为 62.5%。
Anaerobic digestion is a promising waste-to-energy alternative technology. However, the efficiency upgrading for conventional mesophilic digestion of organic solid waste is always indispensable. Employing hyperthermophilic or thermophilic microbial community is one of the viable upgrading alternatives. Given the unavailability of the superior microbial communities, mesophilic digested sludge was used as inoculum, and instantly controlled at 70 °C and 55 °C for acclimation of hyperthermophilic and thermophilic inocula, respectively. Waste activated sludge was continuously and synchronously fed into two digesters. After one round, thermophilic digester achieved stable biogas production rate at 0.22 L L−1d−1, with a methane proportion over 60%, whereas fluctuation was observed in the hyperthermophilic digester, and approximately triple time was needed to reach a relatively stable biogas production rate 0.12 L L−1d−1. Nevertheless, higher hydrolysis ratio 24.4% was observed in the hyperthermophilic digester despite the lower biogas production. Therefore, methanogenesis step limited the whole anaerobic process for the hyperthermophilic digestion, and digestion at 70 °C was appropriate as a pre-fermentation stage to enhanced hydrolysis. The genusMethanothrixproportion in the thermophilic digester gradually decreased, while another acetoclastic genus Methanosarcina ultimately was acclimated to the dominant methanogen. In addition toMethanothrix, hydrogenotrophic archaea became competitive in the hyperthermophilic digester, withMethanothermobacterdominant at 22.6%. The genus Psychrobacter, affiliated to the phylum Proteobacteria could survive better than the others at 70 °C, with a final proportion of 62.5%.