Bioelectrochemical enhancement of methane production in anaerobic digestion of food waste

• Published in: International journal of hydrogen energy 2019-01, Vol.44 (4), p.2081-2090
• Main Authors: Choi, Jae-Min, Lee, Chae-Young
• Format: Article
• Language: English
• Subjects: Anaerobic digestion; Food waste; Microbial electrolysis cells; Response surface methodology; Taguchi method
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2018.08.153

This study was conducted to optimize microbial electrolysis cells (MECs) + anaerobic digestion (AD) using integrated Taguchi method and response surface methodology (RSM). The MECSs were applied to enhance the efficiency of AD using food waste as substrate. Using Taguchi method and RSM, the optimum conditions of the MEC + AD were applied voltage (1.2 V), substrate (2.4 g COD/L) and ratio of reactor volume and electrode area (0.33 m3/m2), respectively. The results of the modified Gompertz and dual-pool 1st order showed that the maximum methane yield, maximum methane production rate, and rate constant for rapidly degradable substrate were 1.2, 1.3 and 1.5 fold higher than those of the AD, respectively. Microbial communities analyses indicated that acetoclastic methanogens were initially floating in MEC + AD reactor, but they became attached onto electrodes over time. •The substrate concentration, applied voltage and RRE were key factors of AD + BESs.•The optimal key factors conditions of 2.4 g/L, 1.2 V and 0.33 m3/m2 were obtained from RSM.•Acetoclastic methanogens were dominant on electrodes.