Scaling up Microbial Fuel Cells for Treating Swine Wastewater

Abstract

Conventional aerobic treatment of swine wastewater, which generally contains 4500-8200 mg L −1 of organic matter, is energy-consuming. The aim of this study was to assess the application of scaled-up microbial fuel cells (MFCs) with different capacities (i.e., 1.5 L, 12 L, and 100 L) for removing organic matter from swine wastewater. The MFCs were single-chambered, consisting of an anode of microbially reduced graphene oxide (rGO) and an air-cathode of platinum-coated carbon cloth. The MFCs were polarized via an external resistance of 3-10 Ω for 40 days for the 1.5 L-MFC and 120 days for the 12L-and 100 L-MFC. The MFCs were operated in continuous flow mode (hydraulic retention time: 3-5 days). The 100 L-MFC achieved an average chemical oxygen demand (COD) removal efficiency of 52%, which corresponded to a COD removal rate of 530 mg L −1 d −1 . Moreover, the 100 L-MFC showed an average and maximum electricity generation of 0.6 and 2.2 Wh m −3 , respectively. Our findings suggest that MFCs can effectively be used for swine wastewater treatment coupled with the simultaneous generation of electricity.

Estimation of total energy requirement for sewage treatment by a microbial fuel cell with a one-meter air-cathode assuming Michaelis–Menten COD degradation

“…Specically, inuents with higher COD resulted in higher COD-RE 24,25 and power density 25,26 but lower CE. 15,27 Increasing the HRT caused further reductions in the COD and current and power densities. 15,17 The mutual interactions between operational and output parameters make the evaluation of MFC performance difficult.…”

A Comprehensive Study of Custom-Made Ceramic Separators for Microbial Fuel Cells: Towards “Living” Bricks

“…To tackle this type of membrane fouling, using alkaline catholyte, or periodic washing of both the cathode and separator can be implemented. Measured by 1) ASTM C373 method, 2) Hg intrusion method, 3) power density normalized by liquid volume of the anode compartment.…”

“…Although a large body of work regarding microbial fuel cell (MFC) technology is still at the laboratory stage, in the recent years, various attempts to evolve the technology towards commercialization have been made. Successful case studies of large-scale systems have been reported [1][2][3][4] (total reactor volume of over 90 L) and an online biosensor based on MFC technology has been released to the market [5]. Recently Trapero et al claimed that MFC technology is economically feasible and sufficiently competitive when compared to conventional wastewater treatment processes such as activated sludge [6].…”

New fragmented electro-active biofilm (FAB) reactor to increase anode surface area and performance of microbial fuel cell

“…The electrochemical fuel cell was discovered early in 1839, but the bioelectricity generation through the microbial fuel cell (MFC) was known in 1910 after Michael Cresse Potter's observation (Flimban et al 2019). However, MFC technology has been facing a critical challenge from commercialization (Do et al 2018;Goto and Yoshida 2019;Guo et al 2020). Hence, it calls for research on several aspects of MFC that require an innovative approach to increase anode surface area, electrode materials fabrication, terminal electron acceptor, proton exchange membrane, reactor design, and microbial dynamics, which needs small-scale investigation (Koroglu et al 2019).…”

“…The major weaknesses of so far invented mechanisms to increase anode surface area were inability to form dense and stable thick EABs, not low-cost option, not possible to manage the anode biofilm thickness through adjusting a controllable variable, and complicated to scale up. However, numerous efforts were conducted; this mystery was still unraveled since the problem was reported (Goto and Yoshida 2019;Guang et al 2020;Li et al 2013). Therefore, a novel approach that increases the anode surface area for microbial attachment and growth is required, which practically contributes to MFC technology advancement (Yu et al 2017).…”