Abstract
Volatile fatty acids (VFA) are organic compounds of great importance for various industries and environmental
processes. Fermentation and anaerobic digestion of organic wastes are promising alternative
technologies for VFA production. However, one of the major challenges is development of sustainable
downstream technologies for VFA recovery. In this study, an innovative microbial bipolar electrodialysis
cell (MBEDC) was developed to meet the challenge of waste-derived VFA recovery, produce hydrogen
and alkali, and potentially treat wastewater. The MBEDC was operated in fed-batch mode. At an applied
voltage of 1.2 V, a VFA recovery efficiency of 98.3%, H2 of 18.4 mL and alkali production presented as pH of
12.64 were obtained using synthetic fermentation broth. The applied voltage, initial VFA concentrations
and composition were affecting the VFA recovery. The energy balance revealed that net energy (5.20
e6.86 kWh/kg-VFA recovered) was produced at all the applied voltages (0.8e1.4 V). The coexistence of
other anionic species had no negative effect on VFA transportation. The VFA concentration was increased
2.96 times after three consecutive batches. Furthermore, the applicability of MBEDC was successfully
verified with digestate. These results demonstrate for the first time the possibility of a new method for
waste-derived VFA recovery and valuable products production that uses wastewater as fuel and bacteria
as catalyst.
© 2015 Elsevier Ltd. All rights reserved.
Original language | English |
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Journal | Water Research |
Volume | 81 |
Pages (from-to) | 188-195 |
ISSN | 0043-1354 |
DOIs | |
Publication status | Published - 2015 |
Keywords
- Volatile fatty acids
- Separation and recovery
- Bioelectrochemical system
- Fermentation
- Hydrogen
- Alkali production