Co-production of biohydrogen and biomethane from food waste and paper waste via recirculated two-phase anaerobic digestion process: Bioenergy yields and metabolic distribution

• Published in: Bioresource technology 2019-03, Vol.276 (C), p.325-334
• Main Authors: Qin, Yu, Li, Lu, Wu, Jing, Xiao, Benyi, Hojo, Toshimasa, Kubota, Kengo, Cheng, Jun, Li, Yu-You
• Format: Article
• Language: English
• Subjects: Biohythane; Co-digestion; Food waste; Organic fraction of municipal solid waste; Paper waste
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2019.01.004

[Display omitted] •Successful co-production of bioH2 and bioCH4 was achieved by R-TPAD process.•The R-TPAD process was feasible to treat OFMSW (FW + PW) with PW content ≤50%.•Increasing PW favored H2 yields by enriching H2-producing bacteria in the process.•The major cellulose-degrading bacteria grew only in the mesophilic phase (2nd stage).•The H2-producers were recirculated to the 1st phase after growing in the 2nd phase. To achieve the co-production of H2 and CH4, co-digestion of food waste (FW) and paper waste (PW) was performed on the recirculated two-phase anaerobic digestion (R-TPAD). The PW content in the feedstock increased from 0% to 20%, 40% and 50% (in total solids) with FW as the rest. The results showed that bioH2 and bioCH4 were simultaneously and stably produced in the long-term operation. With the increasing PW content, the removal efficiency of volatile solids decreased slightly from 84.9% to 78.4%; the bioH2 yields increased from 50 to 79 NL-H2/kg-VSfed while the bioCH4 yields decreased from 426 to 329 NL-CH4/kg-VSfed. With the fixed amount of FW, adding PW could significantly increase the total bioenergy yields. The relative abundance showed that the key H2-producing bacteria, Caproiciproducens and Thermoanaerobacterium, increased after PW addition. The microbial distribution suggests that the H2-producers were recirculated to the first stage after proliferating in the second stage.