Abstract

A microbial electrolysis cell-assisted anaerobic digester (MEC-AD) was operated with vacuum toilet blackwater at different applied voltages (0–1.6 V) at room temperature (R20). A parallel MEC-AD was operated at 35 °C (R35) to provide a kinetics index at mesophilic temperature. Both reactors failed at 1.6 V due to the alkaline pH created by anodic corrosion. In R20, the best performance was observed at 1.2 V, with methane yield, COD removal, hydrolysis and acidogenesis efficiency increased by 59.9%, 27.0%, 52.0%, and 44.9%, respectively, compared to those of 0 V. Enrichment of hydrolytic and syntrophic bacteria (e.g., Clostridium, Bacteroidales, Sedimentibacter, Syntrophomonas) and increased abundance of genes encoding complex organics (e.g., proteins, carbohydrates, lipids) metabolism in R20 at 1.2 V corresponded to the enhanced hydrolysis/acidogenesis processes. R20 at 1.2 V generated 1.16 times more net energy than R35 at the optimum voltage for methane yield (0.8 V), indicating ambient temperature operation of MEC-AD systems would be a more sustainable strategy.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.