This study examined a two-stage dynamic membrane bioreactor (DMBR) system for biohydrogen and biomethane production from food waste (FW) in mesophilic condition. The two-stage DMBR system enabled high-rate H2 and CH4 production from particulate feedstock by enhanced microorganism retention. Chemical energy in FW was recovered up to 79% as renewable energy. The highest average hydrogen production rate of 7.09 ± 0.42 L/L-d was observed at a hydraulic retention time (HRT) of 8 h in the H2-DMBR, while the highest CH4 average production rate of 0.99 ± 0.02 L/L-d was observed at an HRT of 6 d in the CH4-DMBR. The high specific methanogenic activity of 71.7 mL CH4/g VSS-d was maintained at the short HRT, which also contributed to the high MPR. The genus Clostridium was dominant in the H2-DMBR, while bacterial and archaeal populations in the CH4-DMBR were dominated by the class Clostridia and genera Methanobacterium and Methanosaeta, respectively.
Keywords: Acetate capacity number; Biohydrogen; Biomethane; Clostridia; Dynamic membrane bioreactor; Food waste.
Copyright © 2022 Elsevier Ltd. All rights reserved.