Dissimilatory nitrate reduction to ammonium (DNRA) received more attention for its ability to recover ammonium. This study investigated the possibility of low-frequency infrared electromagnetic field (IR-EMF) to improve DNRA. The optimal IR-EMF intensity of 0.04 μT could effectively improve DNRA activity of nonwoven fabric membrane bioreactors. In the long-term operation, the average ammonium conversion efficiency was enhanced by 117.7% and 62.5% under 0.04 μT and 0.06 μT IR-EMF, respectively. The highest nrfA-gene abundance and potential DNRA rate were obtained under 0.04 μT IR-EMF exposure. Bacteroidetes fragilis, Shewanelle oneidensis MR-1, and Thauera sp. RT1901 were selected to investigate the dynamic response of nitrogen transformation and energy metabolism to IR-EMF. The transcriptome sequencing and RT-qPCR results suggested that IR-EMF could enhance both denitrification and DNRA process, mainly by improving ATP synthesis to boost metabolic activity. This study provided an efficient method for the nitrogen recovery via DNRA process by applying IR-EMF.

硝酸盐异化还原铵（DNRA）因其回收铵的能力而受到更多关注。本研究探讨了低频红外电磁场 (IR-EMF) 改善 DNRA 的可能性。最佳IR-EMF强度为0.04 μT可以有效提高非织造布膜生物反应器的DNRA活性。在长期运行中，在0.04 μT和0.06 μT IR-EMF下，平均铵转化效率分别提高了117.7%和62.5%。在 0.04 μT IR-EMF 暴露下获得了最高的 nrfA 基因丰度和潜在 DNRA 率。脆弱拟杆菌、Shewanelle oneidensis MR-1 和 Thauera sp。选择RT1901来研究氮转化和能量代谢对IR-EMF的动态响应。转录组测序和 RT-qPCR 结果表明，IR-EMF 可以增强反硝化和 DNRA 过程，主要是通过改善 ATP 合成来增强代谢活性。本研究提供了一种应用红外电磁场通过 DNRA 工艺回收氮的有效方法。