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Updated: Jul 23, 2025
09:50
Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
12.8K
Simultaneous denitrification and electricity generation in a methane-powered bioelectrochemical system
Long Chen1, Yanli Guo1, Shaohui Zhang1,2
1School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan, China.
Summary
This study demonstrates a novel bioelectrochemical system (BES) that simultaneously removes methane and nitrate pollution. The developed denitrifying anaerobic methane oxidation BES efficiently converts methane into electricity while purifying water.
Area of Science:
- Environmental Science
- Environmental Engineering
- Electrochemistry
Background:
- Bioelectrochemical systems (BESs) offer a promising approach for controlling nitrate pollution.
- The use of methane as an electron donor for denitrification in BESs is not well-understood.
- Addressing nitrate pollution is crucial for environmental protection and water quality.
Purpose of the Study:
- To investigate the feasibility of using methane as an electron donor for denitrification in a BES.
- To establish and characterize a denitrifying anaerobic methane oxidation BES (DAMO-BES).
- To assess the efficiency of simultaneous methane and nitrate removal and electricity generation.
Main Methods:
- Startup of a DAMO-BES using effluent from existing BESs as inoculum.
- Operation of the DAMO-BES with a phosphate buffer solution at controlled pH and temperature.
- Metagenomic analysis to identify microbial communities and functional genes involved in methane oxidation and denitrification.
Main Results:
- Successful startup of the DAMO-BES within 92 days.
- Achieved maximum removal loads of 0.23 mmol/d for methane, 551.0 mg N/m³ /d for nitrate, and 64.0 mg N/m³ /d for total nitrogen.
- Obtained a peak voltage of 93 mV, anodic coulombic efficiency of 6.99%, and maximum power density of 219.86 mW/m³.
- Metagenomics revealed dominant denitrifying bacteria in the cathode and methanotrophs/methanogens in the anode, converting methane via reverse methanogenesis.
Conclusions:
- The DAMO-BES is a viable technology for simultaneous methane and nitrate removal.
- The system effectively converts methane into electricity while purifying wastewater.
- Methylocystis species play a key role in mediating anaerobic methane oxidation at the anode and denitrification at the cathode.
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