Effect of adjusting inlet/outlet location on the power performance of a continuous type of microbial fuel cells

Abstract

Microbial fuel cells (MFCs) are an essential technology in the treatment of wastewater through a series of biochemical reaction processes while generating bioenergy. The advancement of MFCs has been extensively noted, however, certain limitations in performance such as low power density and subpar wastewater treatment hinder its up-scale and commercialization. In addition, the prototyping of MFCs and experimental approach in enhancing its performance is time-consuming and costly. To address these concerns, this study proposes a three-dimensional (3D) numerical model of the continuous type of dual-chambers MFCs to redesign and investigate the effect of changing the inlet and outlet locations. By evaluating the locations of the inlet and outlet, the overall performance of the MFC is projected to improve by addressing the uneven biomass distribution in the electrodes and the uneven concentration of acetic in the solution. With the appropriate changes in the input and output locations, the results revealed that the total current density was increased by 5%. In addition, the maximum percentage of the gap between model A and model B is increased from the original 5% to 8% under 1.5 times the flow rate. This fact implies that an increase in flow rate results in a greater influence of flow field in vortex zone on the performance of MFC. The findings of this work will be useful for the up-scale usage of MFCs for wastewater treatment in the future.