Huang Xiao, Xing Yixiao, Wang Hongjie, Dai Zhongyi, Chen Tiantian
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing, China.
Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, China.
Front Microbiol. 2022 Jan 26;12:811697. doi: 10.3389/fmicb.2021.811697. eCollection 2021.
This study aimed to explore the performance of denitrification deep-bed filter (DN-DBF) to treat municipal sewage for meeting a more stringent discharge standard of total nitrogen (TN) (10.0 mg L). A lab-scale DN-DBF was conducted to optimize operation parameters and reveal the microbiological mechanism for TN removal. The results showed that more than 12.7% TN removal was obtained by adding methanol compared with sodium acetate. The effluent TN concentration reached 6.0-7.0 mg L with the optimal influent carbon and nitrogen ratio (C/N) and hydraulic retention time (HRT) (3:1 and 0.25 h). For the nitrogen removal mechanism, were dominant denitrification floras with an abundance of 6-10%. Though large TN was removed at the top layer of DN-DBF, microbial richness and diversity at the middle layer were higher than both ends. However, the relative abundance of nitrite reductase enzymes (EC1.7.2.1) gradually increases as the depth increases; conversely, the relative abundance of nitrous oxide reductase gradually decreased.
本研究旨在探讨反硝化深床滤池（DN-DBF）处理城市污水以满足更严格的总氮（TN）排放标准（10.0 mg/L）的性能。开展了实验室规模的DN-DBF实验，以优化运行参数并揭示总氮去除的微生物机制。结果表明，与添加乙酸钠相比，添加甲醇可使总氮去除率超过12.7%。在最佳进水碳氮比（C/N）和水力停留时间（HRT）（3:1和0.25 h）条件下，出水总氮浓度达到6.0 - 7.0 mg/L。对于脱氮机制， 是优势反硝化菌群，丰度为6% - 10%。虽然在DN-DBF顶层去除了大量总氮，但中层的微生物丰富度和多样性高于两端。然而，亚硝酸还原酶（EC1.7.2.1）的相对丰度随深度增加而逐渐增加；相反，一氧化二氮还原酶的相对丰度逐渐降低。
