TY - JOUR
T1 - The effect of start-up on energy recovery and compositional changes in brewery wastewater in bioelectrochemical systems
AU - Haavisto, Johanna
AU - Kokko, Marika
AU - Lakaniemi, Aino-Maija
AU - Sulonen, Mira
AU - Puhakka, Jaakko
N1 - Funding Information:
This work was supported by the Academy of Finland (New Indigo ERA-Net Energy 2014; Project no. 283013 ) and Maa- ja vesitekniikan tuki ry -foundation.
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2020/4
Y1 - 2020/4
N2 - Start-up of bioelectrochemical systems (BESs) fed with brewery wastewater was compared at different adjusted anode potentials (−200 and 0 mV vs. Ag/AgCl) and external resistances (50 and 1000 Ω). Current generation stabilized faster with the external resistances (9 ± 3 and 1.70 ± 0.04 A/m3 with 50 and 1000 Ω, respectively), whilst significantly higher current densities of 76 ± 39 and 44 ± 9 A/m3 were obtained with the adjusted anode potentials of −200 and 0 mV vs. Ag/AgCl, respectively. After start-up, when operated using 47 Ω external resistance, the current densities and Coulombic efficiencies of all BESs stabilized to 9.5 ± 2.9 A/m3 and 12 ± 2%, respectively, demonstrating that the start-up protocols were not critical for long-term BES operation in microbial fuel cell mode. With adjusted anode potentials, two times more biofilm biomass (measured as protein) was formed by the end of the experiment as compared to start-up with the fixed external resistances. After start-up, the organics in the brewery wastewater, mainly sugars and alcohols, were transformed to acetate (1360 ± 250 mg/L) and propionate (610 ± 190 mg/L). Optimized start-up is required for prompt BES recovery, for example, after process disturbances. Based on the results of this study, adjustment of anode potential to −200 mV vs. Ag/AgCl is recommended for fast BES start-up.
AB - Start-up of bioelectrochemical systems (BESs) fed with brewery wastewater was compared at different adjusted anode potentials (−200 and 0 mV vs. Ag/AgCl) and external resistances (50 and 1000 Ω). Current generation stabilized faster with the external resistances (9 ± 3 and 1.70 ± 0.04 A/m3 with 50 and 1000 Ω, respectively), whilst significantly higher current densities of 76 ± 39 and 44 ± 9 A/m3 were obtained with the adjusted anode potentials of −200 and 0 mV vs. Ag/AgCl, respectively. After start-up, when operated using 47 Ω external resistance, the current densities and Coulombic efficiencies of all BESs stabilized to 9.5 ± 2.9 A/m3 and 12 ± 2%, respectively, demonstrating that the start-up protocols were not critical for long-term BES operation in microbial fuel cell mode. With adjusted anode potentials, two times more biofilm biomass (measured as protein) was formed by the end of the experiment as compared to start-up with the fixed external resistances. After start-up, the organics in the brewery wastewater, mainly sugars and alcohols, were transformed to acetate (1360 ± 250 mg/L) and propionate (610 ± 190 mg/L). Optimized start-up is required for prompt BES recovery, for example, after process disturbances. Based on the results of this study, adjustment of anode potential to −200 mV vs. Ag/AgCl is recommended for fast BES start-up.
KW - Adjusted anode potential
KW - Brewery wastewater
KW - External resistance
KW - Microbial fuel cell
KW - Process recovery
KW - Start-up protocol
UR - http://www.scopus.com/inward/record.url?scp=85075970236&partnerID=8YFLogxK
U2 - 10.1016/j.bioelechem.2019.107402
DO - 10.1016/j.bioelechem.2019.107402
M3 - Article
SN - 1567-5394
VL - 132
JO - Bioelectrochemistry
JF - Bioelectrochemistry
M1 - 107402
ER -
