Liu Junxing, Chen Zhenguo, Zeng Chenxi, Lin Mi, Xia Libin, Kong Xiangfa, Liu Yafei, Huang Mingzhi
Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, School of Environment, South China Normal University, Guangzhou 510006, PR China; SCNU (NAN' AN) Green and Low-carbon Innovation Center & Guangdong Provincial Engineering Research Center of Intelligent Low-carbon Pollution Prevention and Digital Technology, South China Normal University, Guangzhou 510006, PR China.
Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, School of Environment, South China Normal University, Guangzhou 510006, PR China; SCNU (NAN' AN) Green and Low-carbon Innovation Center & Guangdong Provincial Engineering Research Center of Intelligent Low-carbon Pollution Prevention and Digital Technology, South China Normal University, Guangzhou 510006, PR China.
Bioresour Technol. 2025 Oct;434:132790. doi: 10.1016/j.biortech.2025.132790. Epub 2025 Jun 16.
Low carbon-to-nitrogen ratio remains a critical barrier to achieving efficient nitrogen removal from municipal wastewater by partial denitrification/anammox (PD/A) process. This study introduces a novel strategy that enhances PD/A performance by deeply utilizing in-situ carbon sources through thermal pretreatment. Specifically, heating at 100 °C for 30 min increased soluble chemical oxygen demand (sCOD)/NO-N ratio from 1.47 ± 0.38 to 2.02 ± 0.70, leading to a 12 ± 7 % improvement in nitrogen removal efficiency during long-term operation. Unlike traditional external carbon addition, the thermal pretreatment promoted the release of tyrosine-like proteins and humic acid-like substances, which facilitated denitrification. Despite Candidatus Brocadia dominance, the composition shift in organic matter enriched key denitrifiers including OLB8, unclassified_c_OLB14, and unclassified_c_SJA-28, alongside increased carbon metabolism-related gene abundance. These findings provide new insight into exploiting in-situ carbon for enhancing nitrogen removal, and offer theoretical guidance for advancing the practical application of the PD/A process for municipal wastewater.
低碳氮比仍然是通过部分反硝化/厌氧氨氧化（PD/A）工艺从城市废水中实现高效脱氮的关键障碍。本研究引入了一种新策略，即通过热预处理深度利用原位碳源来提高PD/A性能。具体而言，在100℃下加热30分钟可使可溶性化学需氧量（sCOD）/NO-N比从1.47±0.38提高到2.02±0.70，从而在长期运行期间使脱氮效率提高12±7%。与传统的外部碳添加不同，热预处理促进了类酪氨酸蛋白和类腐殖酸物质的释放，这有利于反硝化作用。尽管以“Candidatus Brocadia”为主导，但有机质的组成变化富集了关键的反硝化菌，包括OLB8、未分类的_c_OLB14和未分类的_c_SJA-28，同时与碳代谢相关的基因丰度增加。这些发现为利用原位碳提高脱氮提供了新的见解，并为推进PD/A工艺在城市废水处理中的实际应用提供了理论指导。
