Year-end Sale % OFF 
Abstract
Energy self-sufficiency is a highly desirable goal of sustainable wastewater treatment. Herein, a combined system of a microbial fuel cell and an intermittently aerated biological filter (MFC-IABF) was designed and operated in an energy self-sufficient manner. The system was fed with synthetic wastewater (COD = 1000 mg L−1) in continuous mode for more than 3 months at room temperature (~25 °C). Voltage output was increased to 5 ± 0.4 V using a capacitor-based circuit. The MFC produced electricity to power the pumping and aeration systems in IABF, concomitantly removing COD. The IABF operating under an intermittent aeration mode (aeration rate 1000 ± 80 mL h−1) removed the residual nutrients and improved the water quality at HRT = 7.2 h. This two-stage combined system obtained 93.9% SCOD removal and 91.7% TCOD removal (effluent SCOD = 61 mg L−1, TCOD = 82.8 mg L−1). Energy analysis indicated that the MFC unit produced sufficient energy (0.27 kWh m−3) to support the pumping system (0.014 kWh m−3) and aeration system (0.22 kWh m−3). These results demonstrated that the combined MFC-IABF system could be operated in an energy self-sufficient manner, resulting to high-quality effluent.
Highlights
To achieve actual energy self-sufficient wastewater treatment process with MFC-based combined system, effective methods of boosting MFC voltage are needed
This study focuses on an innovative concept proposed for in-situ utilization of generated electricity to achieve an energy self-sufficient wastewater treatment process using a combined MFC and intermittently aerated biological filter (IABF) system
During the charging cycle, when MFC was connected to capacitors, the voltage of MFC rapidly decreased to 100 ± 5 mV gradually increased to 400 ± 10 mV
Summary
The relatively faster substrate degradation rate reflected a higher efficiency of IABF to the entire COD removal This wastewater treatment performance could be further enhanced through optimizing the reactor design and operating conditions including increasing volumetric ratio of MFC, increasing HRT in IABF (Table S1), and charging and discharging time optimization. COD treatment efficiency in the combined MFC-IABF achieved more than 90%, while the corresponding value for the conventional activated sludge process was relatively lower, suggesting the feasibility of the combined system as a wastewater-treatment role. The DO concentration fluctuated around 2.7 mg L−1 compared to 2 mg L−1 in conventional aerobic treatment process, an indication that this could not lead to significant change in COD removal[19,20] This IABF reactor operated in concert with MFC for more than 3 months without any backwashing.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
