Progress of complete ammonia oxidization throughout the wastewater treatment system
HE Zi-xuan1, CHEN Shi1, XU Yi-feng1, LIANG Chuan-zhou1, PENG Lai1,2
1. Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Wuhan 430070, China; 2. Shenzhen Research Institute of Wuhan University of Technology, Shenzhen 518000, China
Abstract：The discovery of complete ammonia-oxidizing bacteria (comammox) provided a novel direction for improving nitrification efficiency in wastewater treatment systems. The potential of their metabolic pathways and functional genes for efficient nitrogen an d carbon removal from wastewater was demonstrated. However, strategies to achieve robust comammox enrichment remained controversial. Further investigations were required to characterize the specific contributions to ammonia removal and nitrous oxide (N2O) production during the nitrification process. The technical strategies for efficient comammox enrichment and the impacts of key factors including environmental substrate concentration, dissolved oxygen, operational processes, and temperature on the selective enrichment of comammox were summarized. Chlorate was employed as a specific inhibitor targeting comammox in combination with 1-octyne to construct a dual-inhibitor experimental system, which was capable of clarifying the nitrification contribution and N2O emission potential of comammox in wastewater treatment systems.
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