title: The effect of flow modes and electrode combinations on the performance of a multiple module microbial fuel cell installed at wastewater treatment plant.
abstract: A larger (6.1 L) MFC stack made in a scalable configuration was constructed with four anode modules and three (two-sided) cathode modules, and tested at a wastewater treatment plant for performance in terms of chemical oxygen demand (COD) removal and power generation. Domestic wastewater was fed either in parallel (raw wastewater to each individual anode module) or series (sequentially through the chambers), with the flow direction either alternated every one or two days or kept fixed in a single direction over time. The largest impact on performance was the wastewater COD concentration, which greatly impacted power production, but did not affect the percentage of COD removal. With higher COD concentrations (∼500 mg L-1) and alternating flow conditions, power generation was primarily limited by the cathode specific area. In alternating flow operation, anode modules connected to two cathodes produced an average maximum power density of 6.0 ± 0.4 W m-3, which was 1.9 ± 0.2 times that obtained for anodes connected to a single cathode. In fixed flow operation, a large subsequent decrease in COD influent concentration greatly reduced power production independent of reactor operation in parallel or serial flow modes. Anode modules connected to two cathodes did not consistently produce more power than the anodes connected to a single cathode, indicating power production became limited by restricted anode performance at low CODs. Cyclic voltammetry and electrochemical impedance spectroscopy data supported restricted anode performance with low COD. These results demonstrate that maintaining power production of MFC stack requires higher influent and effluent COD concentrations. However, overall performance of the MFC in terms of COD removal was not affected by operational modes.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No. 73 Huanghe Road, Nangang District, Harbin 150090, PR China.
authors.forename: Weihua
authors.initials: W
authors.lastname: He
authors.affiliation: Department of Civil & Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, USA.
authors.forename: Maxwell J
authors.initials: MJ
authors.lastname: Wallack
authors.affiliation: Department of Civil & Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, USA.
authors.forename: Kyoung-Yeol
authors.initials: KY
authors.lastname: Kim
authors.affiliation: Department of Civil & Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, USA; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Civil & Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, USA.
authors.forename: Wulin
authors.initials: W
authors.lastname: Yang
authors.affiliation: Department of Civil & Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, USA; Department of Civil & Environmental Engineering, Louisiana State University, Baton Rouge, LA 16802, USA.
authors.forename: Xiuping
authors.initials: X
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No. 73 Huanghe Road, Nangang District, Harbin 150090, PR China. Electronic address: yujief@hit.edu.cn.
authors.forename: Yujie
authors.initials: Y
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No. 73 Huanghe Road, Nangang District, Harbin 150090, PR China; Department of Civil & Environmental Engineering, Penn State University, 231Q Sackett Building, University Park, PA 16802, USA. Electronic address: blogan@psu.edu.
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Logan
mesh_terms: D001674:Bioelectric Energy Sources; D057919:Biological Oxygen Demand Analysis; D004560:Electricity; D004566:Electrodes; D062065:Wastewater
chemical_list: D062065:Wastewater
keywords: Alternating flow; Domestic wastewater treatment; Electrode combinations; Microbial fuel cell; Multi-module reactor