Methane mitigation via the nitrite-DAMO process induced by nitrate dosing in sewers

Zhiqiang Zuo; Yaxin Xing; Tao Liu; Min Zheng; Xi Lu; Yan Chen; Guangming Jiang; Peng Liang; Xia Huang; Yanchen Liu

doi:10.1016/j.watres.2024.121701

Methane mitigation via the nitrite-DAMO process induced by nitrate dosing in sewers

Water Res. 2024 Apr 30:257:121701. doi: 10.1016/j.watres.2024.121701. Online ahead of print.

Authors

Zhiqiang Zuo¹, Yaxin Xing², Tao Liu³, Min Zheng⁴, Xi Lu⁵, Yan Chen⁶, Guangming Jiang⁶, Peng Liang², Xia Huang², Yanchen Liu⁷

Affiliations

¹ State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia; National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China.
² State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
³ Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia; Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong 999077, China.
⁴ Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia; Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
⁵ Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD 4072, Australia.
⁶ School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
⁷ State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China. Electronic address: liuyc@mail.tsinghua.edu.cn.

PMID: 38733962
DOI: 10.1016/j.watres.2024.121701

Abstract

Nitrate or nitrite-dependent anaerobic methane oxidation (n-DAMO) is a microbial process that links carbon and nitrogen cycles as a methane sink in many natural environments. This study demonstrates, for the first time, that the nitrite-dependent anaerobic methane oxidation (nitrite-DAMO) process can be stimulated in sewer systems under continuous nitrate dosing for sulfide control. In a laboratory sewer system, continuous nitrate dosing not only achieved complete sulfide removal, but also significantly decreased dissolved methane concentration by ∼50 %. Independent batch tests confirmed the coupling of methane oxidation with nitrate and nitrite reduction, revealing similar methane oxidation rates of 3.68 ± 0.5 mg CH₄ L^-1 h^-1 (with nitrate as electron acceptor) and 3.57 ± 0.4 mg CH₄ L^-1 h^-1 (with nitrite as electron acceptor). Comprehensive microbial analysis unveiled the presence of a subgroup of the NC10 phylum, namely Candidatus Methylomirabilis (n-DAMO bacteria that couples nitrite reduction with methane oxidation), growing in sewer biofilms and surface sediments with relative abundances of 1.9 % and 1.6 %, respectively. In contrast, n-DAMO archaea that couple methane oxidation solely to nitrate reduction were not detected. Together these results indicated the successful enrichment of n-DAMO bacteria in sewerage systems, contributing to approx. 64 % of nitrite reduction and around 50 % of dissolved methane removal through the nitrite-DAMO process, as estimated by mass balance analysis. The occurrence of the nitrite-DAMO process in sewer systems opens a new path to sewer methane emissions.

Keywords: Anaerobic methane oxidation; Dissolved methane removal; Nitrate dosing; Nitrite-dependent anaerobic methane oxidation (nitrite-DAMO); Sewer; Sulfide control.