Wang Haiyue, Li Zhihao, Peng Ling, Tang Xi, Lin Yuan, Yang Dongli, Geng Jinju, Ren Hongqiang, Xu Ke
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, PR China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, PR China.
Bioresour Technol. 2021 Dec;341:125747. doi: 10.1016/j.biortech.2021.125747. Epub 2021 Aug 12.
Advanced nitrogen removal of effluent discharged from secondary treatment systems can avoid eutrophication. However, the lack of biodegradable organics limits biodenitrification. Packed bed reactors filled with carriers with different micromagnetic field (MMF) strengths were used to perform tertiary denitrification. The results showed that MMF significantly improved the denitrification performance, especially at low C/N ratios. Total nitrogen (TN) removal was increased by 4.12% with 0.6 mT MMF when C/N = 4 and increased by 7.06% and 8.06% with 0.3 mT and 0.9 mT MMFs when C/N = 3, respectively. Zooglea, Flavobacterium, and Denitratisoma contributed to the advanced denitrification performance under MMF. In addition, 0.6 mT MMF enhanced nitrogen metabolism and ABC transporter protein and two-component system activities of microorganisms under C/N = 4; 0.3 mT and 0.9 mT MMFs increased nitrogen, carbohydrate, and amino acid metabolism and ABC transporter protein activities under C/N = 3. These findings indicate that MMF has great potential for advanced denitrification from secondary effluent.
二级处理系统排放的废水深度脱氮可避免富营养化。然而，缺乏可生物降解有机物限制了生物反硝化作用。使用填充有不同微磁场（MMF）强度载体的填充床反应器进行三级反硝化。结果表明，微磁场显著提高了反硝化性能，尤其是在低碳氮比时。当碳氮比=4时，0.6 mT微磁场使总氮（TN）去除率提高了4.12%；当碳氮比=3时，0.3 mT和0.9 mT微磁场分别使总氮去除率提高了7.06%和8.06%。菌胶团、黄杆菌和脱氮索菌在微磁场作用下对深度反硝化性能有贡献。此外，0.6 mT微磁场增强了碳氮比=4时微生物的氮代谢、ABC转运蛋白和双组分系统活性；0.3 mT和0.9 mT微磁场提高了碳氮比=3时微生物的氮、碳水化合物和氨基酸代谢以及ABC转运蛋白活性。这些发现表明，微磁场在二级出水深度反硝化方面具有巨大潜力。
