Key Laboratory of Regional Energy Systems Optimization, Ministry of Education, College of Environmental Science and Technology, North China Electric Power University, Beijing 102206, China.
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
Bioresour Technol. 2021 Nov;340:125704. doi: 10.1016/j.biortech.2021.125704. Epub 2021 Aug 2.
Nitrous oxide (NO) emission from wastewater treatment plants (WWTPs) requires urgent mitigation because of its significant contribution to the greenhouse effect. In this study, bioaugmentation was applied in a pilot-scale oxidation ditch with the aerobic denitrifying bacteria strain PCN-1 immobilized on polyurethane biocarriers, which demonstrated effective NO mitigation. Microbial community analysis suggested that the bioaugmentation facilitated a symbiotic relationship of the bacterial populations between the activated sludge and the biocarriers. The denitrifying bacteria with well-known NO reducing capabilities predominated on the biocarriers. Correspondingly, the increases of denitrifying genes and NO and NO reductase provided evidence for the enhanced genetic potential for NO and NO reduction. Besides, the enriched comammox Nitrospira on the biocarriers is proposed as another significant driver for NO mitigation by avoiding nitrite accumulation. In addition, the bioaugmentation enhanced the stability and recovery capability of the system in the ammonia overload and aeration failure shock tests.
污水处理厂（WWTPs）中的一氧化二氮（NO）排放需要紧急缓解，因为它对温室效应的贡献很大。在这项研究中，生物强化技术应用于一个带有固定在聚氨酯生物载体上的好氧反硝化细菌菌株 PCN-1 的氧化沟中，结果表明该方法可有效减少 NO 的排放。微生物群落分析表明，生物强化促进了活性污泥和生物载体之间细菌种群的共生关系。具有众所周知的 NO 还原能力的反硝化细菌在生物载体上占主导地位。相应地，增加的反硝化基因和 NO 和 NO 还原酶为增强 NO 和 NO 还原的遗传潜力提供了证据。此外，生物载体上富集的 comammox Nitrospira 被认为是另一个通过避免亚硝酸盐积累来减少 NO 的重要驱动因素。此外，生物强化增强了系统在氨过载和曝气故障冲击测试中的稳定性和恢复能力。
