Sui Yuan, Cui You-Wei, Yan Hui-Juan, Yang Rui-Chun
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing, 100124, China.
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing, 100124, China.
J Environ Manage. 2025 Aug;390:126250. doi: 10.1016/j.jenvman.2025.126250. Epub 2025 Jun 20.
Heterotrophic nitrification-aerobic denitrification (HN-AD) has attracted increasing attentions due to its novel advantages of aerobic total inorganic nitrogen (TIN) removal in a single reactor. However, the low relative abundance of the HN-AD bacterial community within activated sludge confines the practical utilization of HN-AD. This study explored the effects of feeding modes (anoxic feeding for 10 min or 1 min compared with aerobic feeding), on nitrogen removal and the functional bacterial population in sequencing batch reactors. Aerobic feeding (shortening anoxic feeding duration to 0 min) led to the highest TIN removal (88.42 ± 4.00 %). Shortening anoxic feeding duration from 10 min to 1 min also increased TIN removal efficiency from 53.16 ± 7.48 % to 73.31 ± 5.92 %. High-throughput sequencing revealed the relative abundance of HN-AD functional bacteria within the aerobic feeding reactor, which increased more than 8.30 times compared with that in the reactor with anoxic feeding for 10 min, the dominant HN-AD bacteria were Comamonadaceae with a relative abundance of 13.90 %. Stoichiometric calculations showed the proportion of organic matter utilized by HN-AD bacteria increased up to 70.78 % with aerobic feeding, suggesting that high carbon availability could be the reason behind the improved TIN removal and HN-AD bacterial enrichment. The results demonstrated that the feeding mode of sequencing batch reactors significantly influenced the HN-AD bacterial population. This study proposed a methodology on highly enriched HN-AD bacteria by altering feeding mode to shorten the anoxic feeding duration, to achieve efficient nitrogen removal while reducing costs and energy consumption.
异养硝化-好氧反硝化（HN-AD）因其在单个反应器中好氧去除总无机氮（TIN）的新颖优势而受到越来越多的关注。然而，活性污泥中HN-AD细菌群落的相对丰度较低，限制了HN-AD的实际应用。本研究探讨了进水模式（与好氧进水相比，缺氧进水10分钟或1分钟）对序批式反应器中氮去除和功能细菌种群的影响。好氧进水（将缺氧进水时间缩短至0分钟）导致最高的TIN去除率（88.42±4.00%）。将缺氧进水时间从10分钟缩短至1分钟也将TIN去除效率从53.16±7.48%提高到73.31±5.92%。高通量测序揭示了好氧进水反应器中HN-AD功能细菌的相对丰度，与缺氧进水10分钟的反应器相比增加了8.30倍以上，主要的HN-AD细菌是丛毛单胞菌科，相对丰度为13.90%。化学计量计算表明，好氧进水时HN-AD细菌利用的有机物比例增加到70.78%，这表明高碳可用性可能是TIN去除改善和HN-AD细菌富集的原因。结果表明，序批式反应器的进水模式显著影响了HN-AD细菌种群。本研究提出了一种通过改变进水模式缩短缺氧进水时间来高度富集HN-AD细菌的方法，以实现高效脱氮，同时降低成本和能耗。
