Biogas upgrading performance and underlying mechanism in microbial electrolysis cell and anaerobic digestion integrated system

Bioresour Technol. 2024 Apr 8:130683. doi: 10.1016/j.biortech.2024.130683. Online ahead of print.ABSTRACTThe productivity and efficiency of two-chamber microbial electrolysis cell and anaerobic digestion integrated system (MEC-AD) were promoted by a complex of anaerobic granular sludge and iron oxides (Fe-AnGS) as inoculum. Results showed that MEC-AD with Fe-AnGS achieved biogas upgrading with a 23%-29% increase in the energy recovery rate of external circuit current and a 26%-31% decrease in volatile fatty acids. The energy recovery rate of MEC-AD remained at 52%-57%, indicating a stable operation performance. The selectively enriched methanogens and electroactive bacteria resulted in dominant hydrogenotrophic and acetoclastic methanogenesis in the cathode and anode chambers. Mechanistic analysis revealed that MEC-AD with Fe-AnGS led to specifically upregulated enzymes related to energy metabolism and electron transfer. Fe-AnGS as inoculum could improve the long-term operation performance of MEC-AD. Consequently, this study provides an efficient strategy for biogas upgrading in MEC-AD.PMID:38599352 | DOI:10.1016/j.biortech.2024.130683

Source: Bioresource Technology - April 10, 2024 Category: Biotechnology Authors: Yufang Wei Wangmi Chen Jiaqi Hou Xuejiao Qi Meiying Ye Ning Jiang Fanhua Meng Beidou Xi Mingxiao Li Source Type: research