Wang Si-Ke, Yu Heng, Zuo Jian-E
State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
Huan Jing Ke Xue. 2020 Nov 8;41(11):5082-5088. doi: 10.13227/j.hjkx.202004267.
The greenhouse gas NO is released during the biological nitrogen removal process. ANAMMOX (anaerobic ammonium oxidation) is regarded as a promising nitrogen removal process for treating municipal wastewater, and the NO emission patterns and mechanisms need further investigation. In this study, batch tests were performed to study the release of NO at different temperatures and substrate concentrations, and the microbial mechanisms of NO emission were discussed. The results showed that the increase of the influent substrate concentration of the ANAMMOX process promoted the release of NO. At 35℃, when the influent nitrite increased from 40 mg·L to 60 mg·L, 120 mg·L, the maximum accumulated concentration of NO increased from 0.5 mg·L to 1.5 mg·L and 2.4 mg·L, accounting for 0.85%, 1.43%, and 1.11% of the total nitrogen removal, respectively. Lowering temperature had an obvious inhibitory effect on ANAMMOX activity. The specific ANAMMOX activity at 15℃ was only 6% of that at 30℃. Furthermore, the intracellular ATP concentration was reduced. At 15℃, the intracellular ATP concentration was 4% of that at 30℃. The decrease in temperature led to a decrease in the release of NO in the ANAMMOX process. When the temperature decreased, the denitrification rate would decrease, leading to a lower NO production rate and lower NO accumulation. 16S rRNA amplicon sequencing showed that ANAMMOX bacteria and were enriched, accounting for 6.9%-13.8% and 1.4%-2.6% of microbial community, respectively. Abundant heterotrophic bacteria were also found in the microbial community. The accumulation of NO in the ANAMMOX process was mainly attributed to denitrifying bacteria producing and consuming NO. This study provides support for controlling NO emission during the ANAMMOX process for treating municipal wastewater.
在生物脱氮过程中会释放温室气体一氧化氮（NO）。厌氧氨氧化（ANAMMOX）被认为是一种有前景的城市污水处理脱氮工艺，其NO排放模式和机制有待进一步研究。本研究通过批次试验研究了不同温度和底物浓度下NO的释放情况，并探讨了NO排放的微生物机制。结果表明，ANAMMOX工艺进水底物浓度的增加促进了NO的释放。在35℃时，当进水亚硝酸盐从40mg·L增加到60mg·L、120mg·L时，NO的最大累积浓度从0.5mg·L增加到1.5mg·L和2.4mg·L，分别占总氮去除量的0.85%、1.43%和1.11%。降低温度对ANAMMOX活性有明显的抑制作用。15℃时的比厌氧氨氧化活性仅为30℃时的6%。此外，细胞内ATP浓度降低。在15℃时，细胞内ATP浓度为30℃时的4%。温度降低导致ANAMMOX过程中NO的释放减少。当温度降低时，反硝化速率降低，导致NO产生率降低和NO积累量降低。16S rRNA扩增子测序表明，厌氧氨氧化菌 和 富集，分别占微生物群落的6.9%-13.8%和1.4%-2.6%。在微生物群落中还发现了大量的异养细菌。ANAMMOX过程中NO的积累主要归因于反硝化细菌产生和消耗NO。本研究为控制城市污水处理ANAMMOX过程中的NO排放提供了支持。
