Establishment and differential performance of hyperthermophilic microbial community during anaerobic self-degradation of waste activated sludge
Establishment and differential performance of hyperthermophilic microbial community during anaerobic self-degradation of waste activated sludge
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废弃活性污泥厌氧自降解过程中超高温微生物群落的建立及差异表现
DOI：
10.1016/j.envres.2020.110035
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发表时间：
2020
影响因子：
8.3
通讯作者：
Lyu Yong-Kang
中科院分区：
文献类型：
--
作者：
Wu Li-Jie;Li Xiao-Xiao;Qin Zhi-Feng;Yang Fan;Zhou Quan;Ren Rui-Peng;Lyu Yong-Kang
超高温厌氧消化，尤其是在 70 °C 的温度下，引起了广泛的关注。为了获得接种和消化特性，分别在超高温（70℃）、高温（55℃）和中温（35℃）条件下进行批量驯化和连续操作实验。从单一来源的废活性污泥（WAS）中成功富集了各个温度下的古细菌。高温消化实现了更高的古菌多样性，接近高温消化的香农指数 2.23，但种群数量没有改善，16S rRNA 基因为 5.99 × 105 拷贝 mL−1。在超高温消化池中，氢营养型产甲烷菌Methanospirillum和Methanothermobacter占主导地位，占27.15%，而初级门Firmicutes则提升至36.31%，其中蛋白水解属CoprothermobacterinFirmicutes占19.50%。消化温度越高，难降解的有机组分转化得越多，分批驯化结束时在 70 °C、55 °C 和 35 °C 时 COD/VS 分别增加到 5.8、5.2 和 4.2 就证明了这一点。此外，WAS 中主要部分蛋白质的最大溶解度也发生在 70°C。在 70 °C 和 55 °C 下实现了类似的水解率（超过 10%）和比水解率（约 0.025 g COD (g VSS·d)−1）。超高温消化的更高水解甚至导致比中温消化更高的甲烷产率。然而，与较高的水解相反，产甲烷限制了 WAS 降解中的超高温消化，尽管通过连续操作几乎完全转化了 VFA，但最终甲烷产量为 71.2 mL g−1VS。
Hyperthermophilic anaerobic digestion, especially at 70 °C, has drawn wide attention. In order to acquire the inoculum and digestion characteristics, batch acclimation and continuous operation experiments were conducted under hyperthermophilic (70 °C), thermophilic (55 °C) and mesophilic (35 °C) conditions, respectively. Archaea at each temperature was successfully enriched from the sole-source waste activated sludge (WAS). Hyperthermophilic digestion achieved higher archaea diversity, close to the Shannon index 2.23 for the thermophilic digestion, but the population were not improved, at a 16S rRNA genes 5.99 × 105copies mL−1. Hydrogenotrophic methanogens,MethanospirillumandMethanothermobacter, dominated in the hyperthermophilic digester, accounting for 27.15%, while the primary phylumFirmicuteswas promoted to 36.31%, with the proteolytic genusCoprothermobacterinFirmicutesat 19.50%. Refractory organic fractions were converted more with a higher digestion temperature, which was demonstrated by the fact that the COD/VS increased to 5.8, 5.2 and 4.2 at 70 °C, 55 °C and 35 °C, respectively, at the end of batch acclimation. In addition, the most solubilization for the dominant fraction protein in the WAS occurred at 70 °C as well. Similar hydrolysis ratio, over 10%, and specific hydrolysis rate, around 0.025 g COD (g VSS·d)−1, were achieved at 70 °C and 55 °C. The higher hydrolysis for hyperthermophilic digestion even resulted in a higher methane yield than that for the mesophilic digestion. Nevertheless, contrary to higher hydrolysis, methanogenesis limited hyperthermophilic digestion in WAS degradation, with an ultimate methane yield 71.2 mL g−1VSadded, despite an almost complete VFA conversion through the continuous operation.