Enhancement of methane production from waste activated sludge using hybrid microbial electrolysis cells-anaerobic digestion (MEC-AD) process - A review

Xue-Ting Wang; Yi-Feng Zhang; Bo Wang; Song Wang; Xue Xing; Xi-Jun Xu; Wen-Zong Liu; Nan-Qi Ren; Duu-Jong Lee; Chuan Chen

doi:10.1016/j.biortech.2021.126641

Enhancement of methane production from waste activated sludge using hybrid microbial electrolysis cells-anaerobic digestion (MEC-AD) process - A review

Bioresour Technol. 2022 Feb:346:126641. doi: 10.1016/j.biortech.2021.126641. Epub 2021 Dec 29.

Authors

Xue-Ting Wang¹, Yi-Feng Zhang², Bo Wang², Song Wang², Xue Xing³, Xi-Jun Xu³, Wen-Zong Liu⁴, Nan-Qi Ren³, Duu-Jong Lee⁵, Chuan Chen⁶

Affiliations

¹ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China; Department of Environmental Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
² Department of Environmental Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
³ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China.
⁴ School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
⁵ Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan.
⁶ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China. Electronic address: cchen@hit.edu.cn.

PMID: 34973405
DOI: 10.1016/j.biortech.2021.126641

Abstract

Hybrid microbial electrolysis cells-anaerobic digestion (MEC-AD) was proved to increase methane productivity and methane yield of waste activated sludge (WAS) by establishing direct interspecies electron transfer method and enriching functional microorganisms. This review first summarized the pretreatment methods of WAS for MEC-AD and then reviewed the reactor configurations, operation parameters, and the economic benefit of MEC-AD. Furthermore, the enhancement mechanisms of MEC-AD were reviewed based on the analysis of thermodynamics and microbial community. It was found that the decrease of hydrogen partial pressure due to the hydrogenotrophic methanogens enriched in cathodic biofilm and direct interspecies electron transfer between exoelectrogens and anode were the core mechanisms for improving acidogenesis, acetogenesis, and methanogenesis. Finally, the potentially technological issues that need to be addressed to increase energy efficiency in large-scale MEC-AD processes were discussed.

Keywords: Anaerobic digestion; Enhancing mechanism; Methane production; Microbial community; Microbial electrolysis cell; Waste activated sludge.

Publication types

Review

MeSH terms

Anaerobiosis
Bioreactors*
Electrolysis
Methane
Sewage*

Substances

Sewage
Methane