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Indexed by:期刊论文

Date of Publication:2018-03-01

Journal:CHEMICAL ENGINEERING JOURNAL

Included Journals:SCIE、EI

Volume:335

Page Number:657-664

ISSN No.:1385-8947

Key Words:Anaerobic digestion; Bio-electrochemical systems; Low-temperature; Low-organic strength wastewater; Syntrophic community

Abstract:This study provides a new approach by using bio-electrochemical systems (BES) to improve the performance of anaerobic digestion (AD) for treating low-organic strength wastewater and recovering energy in the form of CH4. The BES had a relatively higher capability for temperature shock. At an applied voltage of 0.4 V, the BES significantly enhanced both the chemical oxygen demand (COD) removal and CH4 yield efficiency compared with those of the control at operational temperatures of 20, 12, and 8 degrees C. Energy balance evaluation indicated that the net energy obtained from the BES was higher than the energy recovered from the control, suggesting that operation of BES was economically available. Analysis of microbial physiological characteristics elucidated that electrochemical effects stimulated the production of extracellular polymeric substances, suggesting a faster metabolic activity of biomass in the BES. 16S rRNA sequencing showed that genera of H-2-utilizing methanogens, Methanobacterium, Methanoregula, and Methanospirillum, dominated the consortia at low temperatures. On the surfaces of cathodes, considerable enrichments of H-2-producing bacteria, Acetobacteroides and Anaerolinea were observed, implying the formation of H-2-mediated syntrophic communities in the BES. The combined results suggest that operation of BES for low-temperature AD of low-organic strength wastewater will be an attractively potential technology.