Nitrous oxide emission mitigation from biological wastewater treatment – A review

• Published in: Bioresource technology Vol. 362; p. 127747
• Main Authors: Lee, Yu-Jen, Lin, Bin-le, Lei, Zhongfang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2022
• Subjects: Biological wastewater treatment; economic feasibility; life cycle assessment; Metabolic pathway; Metrics analysis; Mitigation strategy; nitrous oxide; Nitrous oxide emission; nitrous oxide production; Nitrous oxide recovery; renewable energy sources; wastewater treatment; Mitigation strategy; Metabolic pathway; Metrics analysis; Biological wastewater treatment; Nitrous oxide recovery; Nitrous oxide emission
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2022.127747

[Display omitted] •N2O removal from wastewater can be realized using biological treatment.•Mechanisms of biological N2O formation and consumption are outlined.•Bacterial strains capable of N2O reduction is a current research focus.•Research needs and prospects of biological N2O removal/valorization are discussed.•Economic analysis on biological N2O removal from wastewater is needed. Nitrous oxide (N2O) emitted from wastewater treatment processes has emerged as a focal point for academic and practical research amidst pressing environmental issues. This review presents an updated view on the biological pathways for N2O production and consumption in addition to the critical process factors affecting N2O emission. The current research trends including the strain and reactor aspects were then outlined with discussions. Last but not least, the research needs were proposed. The holistic life cycle assessment needs to be performed to evaluate the technical and economic feasibility of the proposed mitigation strategies or recovery options. This review also provides the background information for the proposed future research prospects on N2O mitigation and recovery technologies. As pointed out, dilution effects of the produced N2O gas product would hinder its use as renewable energy; instead, its use as an effective oxidizing agent is proposed as a promising recovery option.