Methane-supported nitrate removal from groundwater in a membrane biofilm reactor

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

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Author(s)

Detail(s)

Original languageEnglish
Pages (from-to)71-78
Journal / PublicationWater Research
Volume132
Publication statusPublished - 1 Apr 2018
Externally publishedYes

Abstract

The discovery of denitrifying anaerobic methane oxidation (DAMO) has not only improved our understanding of global methane and nitrogen cycles, but also provided new technology options for removal of nitrate from nitrate-contaminated water. Previous studies have demonstrated DAMO organisms could remove nitrate and nitrite from wastewater under strictly anaerobically conditions. In the study, we investigate the feasibility of nitrate removal from groundwater, which contains dissolved oxygen in addition to nitrate. A membrane biofilm reactor (MBfR), inoculated with DAMO co-culture, was capable of treating synthetic groundwater containing highly contaminated nitrate (50 mg N/L) and oxygen (7–9 mg O2/L), with a maximum volumetric nitrate removal rate of 45 mg N/L-d. Accumulations of acetate and propionate were observed in some transient periods, indicating the possible involvement of acetate and propionate as intermediates in methane oxidation. The 16 S rRNA gene amplicon sequencing revealed that Candidatus Methylomirabilis, a known bacterial DAMO organism able to couple nitrite reduction with anaerobic oxidation of methane (AOM), was the dominant population. No archaeal DAMO organisms that are capable of coupling nitrate to AOM were observed, however, considerable amount of denitrifiers were developed in this system. Based on known metabolisms of these microorganisms and a series of batch studies, it was assumed that methane was oxidized into volatile fatty acids (VFAs) under oxygen-limiting conditions, then the generated VFAs served as carbon sources for these heterotrophic denitrifiers to remove nitrate. This study offers a potential technology for nitrate removal from groundwater by DAMO process in MBfR. © 2017 Elsevier Ltd

Research Area(s)

  • Anaerobic methane oxidation, Denitrifying anaerobic methane oxidation (DAMO), Membrane biofilm reactor, Micro-aerobic methane oxidation, Nitrate removal

Bibliographic Note

Publication details (e.g. title, author(s), publication statuses and dates) are captured on an “AS IS” and “AS AVAILABLE” basis at the time of record harvesting from the data source. Suggestions for further amendments or supplementary information can be sent to lbscholars@cityu.edu.hk.

Citation Format(s)

Methane-supported nitrate removal from groundwater in a membrane biofilm reactor. / Luo, Jing-Huan; Chen, Hui; Yuan, Zhiguo et al.
In: Water Research, Vol. 132, 01.04.2018, p. 71-78.

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review