Bioelectrochemical system for the enhancement of methane production by anaerobic digestion of alkaline pretreated sludge

Xi-Jun Xu; Wan-Qiong Wang; Chuan Chen; Peng Xie; Wen-Zong Liu; Xu Zhou; Xue-Ting Wang; Ye Yuan; Ai-Jie Wang; Duu-Jong Lee; Yi-Xing Yuan; Nan-Qi Ren

doi:10.1016/j.biortech.2020.123000

Bioelectrochemical system for the enhancement of methane production by anaerobic digestion of alkaline pretreated sludge

Bioresour Technol. 2020 May:304:123000. doi: 10.1016/j.biortech.2020.123000. Epub 2020 Feb 12.

Authors

Xi-Jun Xu¹, Wan-Qiong Wang¹, Chuan Chen², Peng Xie¹, Wen-Zong Liu³, Xu Zhou⁴, Xue-Ting Wang¹, Ye Yuan⁵, Ai-Jie Wang⁶, Duu-Jong Lee⁷, Yi-Xing Yuan¹, Nan-Qi Ren¹

Affiliations

¹ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, HeiLongjiang Province 150090, China.
² State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, HeiLongjiang Province 150090, China. Electronic address: echo110244@126.com.
³ Key Laboratory of Environmental Biotechnology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
⁴ Engineering Laboratory of Microalgal Bioenergy, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, China.
⁵ School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, China.
⁶ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, HeiLongjiang Province 150090, China; Key Laboratory of Environmental Biotechnology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
⁷ Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan; Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan.

PMID: 32088625
DOI: 10.1016/j.biortech.2020.123000

Abstract

An increasing interest is devoted to combined microbial electrolysis cell-anaerobic digestion (MEC-AD) system which could convert waste activated sludge into biogas. In this study series tests were initially conducted to study the effect of alkaline pretreatment on AD system and the results showed that alkaline pretreatment could promote the dissolution of organic matters in the sludge and thus improve the methane production. Then, the methane production in combined MEC-AD system fed with alkaline-pretreated sludge was investigated. The results indicated that the methane productions increased by 37% and 42% when applied voltage was 0.5 V and 0.8 V. The microbial electrochemical system strongly promoted the growth of Euryarchaeota (Methanosaeta and Methanobacterium). Meanwhile, the abundance of Paraclostridium increased from 17.9% to 38.5% when applied voltage was 0.8 V, suggesting an enhanced fermentation and acetogenesis process. The results of energy balance estimation indicated that MEC-AD system at 0.5 V could achieve higher net energy output.

Keywords: Alkaline pretreatment; Anaerobic digestion; Bioelectrochemical; Energy balance; Methane production; Waste activated sludge.

MeSH terms

Anaerobiosis
Bioreactors*
Electrolysis
Methane
Sewage*
Waste Disposal, Fluid

Substances

Sewage
Methane