Advances in microbial fuel cells for wastewater treatment
TL;DR: In this article, the problems and applications of microbial fuel cells in wastewater treatment were discussed, and the integration of MFCs with other treatment processes was presented to verify the practicality and effectiveness of the MFC in contaminants removal.
Abstract: Resources scarcity and electricity demand have been dramatically increasing. Wastewater is recognized as one of resources for water, energy and plant fertilizing nutrients. Nevertheless, current wastewater treatment technologies have limitations due principally to their energy- and cost-intensive for achieving the conversion target of wastewater recovery. It is desired to develop a new technology to generate alternatives to conventional energy sources in a sustainable manner. An innovative technology based on the use of microbial fuel cells (MFCs) has been proved as a critical pathway for bioconversion processes towards electricity generation, then for addressing energy and environmental problems. Three special features including energy saving, less sludge production and less energy production make MFCs outstanding compared with the existing technologies. Multiform wastewaters could be efficiently degraded through advancing MFCs alone or integrating MFCs with other processing units. However, the low power density and the high operating cost of MFCs have greatly limited their applications on large-scale problems, and then result in some debates and doubts about their development and applications. Therefore, this paper objectively discussed the problems and applications of MFCs in wastewater treatment. Moreover, the integration of MFCs with other treatment processes was presented to verify the practicality and effectiveness of MFCs in contaminants removal. Furthermore, the primary challenges and opportunities for scaling-up and future applications of MFCs in wastewater were analyzed.
Citations
More filters
TL;DR: In this paper, the development and advancements of electrode and membrane materials for increasing the microbial fuel cell performances in recent years have been discussed and reviewed and discussed the different categories of electrode (anode and cathode) materials with various structural, dimensional, compositions and integrations.
321 citations
TL;DR: In this article, the available Hexavalent chromium (VI) remediation strategies have been comprehensively reviewed for aqueous solutions and a broad range of recent research works have been evaluated.
300 citations
TL;DR: A first attempt to provide a prototype framework that can assess ecological vulnerability and evaluate potential impacts of natural, social, economic, environmental pollution, and human health elements on ecological vulnerability with integrating spatial analysis of Geographic Information System (GIS) method and multi-criteria decision analysis (MCDA).
213 citations
Cites background from "Advances in microbial fuel cells fo..."
...…and deterioration due to climate change, economy development and humankind activities (Hua et al., 2015; Mitchell et al., 2015; Farley and Voinov, 2016; Virapongse et al., 2016; Blanco et al., 2017; Liang et al., 2017a, 2017b; Chen et al., 2016; Li et al., 2017; He et al., 2017; Chen et al., 2017)....
[...]
TL;DR: Several aspects of MFCs such as anode, cathode and membrane are explored in an effort to overcome the practical challenges of this system.
200 citations
TL;DR: In this paper, a comprehensive discussion on fundamental concepts and applications of renewable energy-driven electrochemical technologies for treating hazardous pollutants in wastewater and contaminated soils is presented, whereas the next two sections focused on the most applied technologies for powering these electrochemical devices: solar photovoltaic (PV) and the wind turbines (Section 4).
Abstract: Electrochemical wastewater and soil treatments are exciting set of technologies that has been well-studied over the recent years as one of the most-effective remediation techniques for the removal of hazardous pollutants from liquids effluents and soil. The main requirement of these technologies is electricity and their sustainability can be largely improved if they are powered by renewable energy sources. Likewise, this green energy powering can help to apply these technologies in remote areas, such as rural communities in developing countries, where no electricity grid is available. This review presents a comprehensive discussion on fundamental concepts and applications of renewable energy driven electrochemical technologies for treating hazardous pollutants in wastewater and contaminated soils. In the first section, the fundamentals of different electrochemical remediation technologies are presented, whereas the next two sections focused on the most applied technologies for powering these electrochemical devices: the solar photovoltaic (PV) (Section 3) and the wind turbines (Section 4). After that, the non-near future is faced with the study of the principles of biomass energy production and how bioelectrochemical systems are starting to be evaluated for powering electrochemical technologies (Section 5). Then, new approaches in the renewable energy driven electrochemical technologies such as triboelectric nanogenerators and photocatalytic fuel cells are described in Section 6. The last section focused on the challenges expected for the near future, describing the most promising storage system and evaluating the scale-up, environmental and economic concerns of the technologies studied in this work.
183 citations
References
More filters
TL;DR: How bacteria use an anode as an electron acceptor and to what extent they generate electrical output is discussed and the MFC technology is evaluated relative to current alternatives for energy generation.
2,042 citations
TL;DR: An analysis based on available anode surface area and maximum bacterial growth rates suggests that mediatorless MFCs may have an upper order-of-magnitude limit in power density of 10(3) mW/m2.
Abstract: Microbial fuel cells (MFCs) are typically designed as a two-chamber system with the bacteria in the anode chamber separated from the cathode chamber by a polymeric proton exchange membrane (PEM). Most MFCs use aqueous cathodes where water is bubbled with air to provide dissolved oxygen to electrode. To increase energy output and reduce the cost of MFCs, we examined power generation in an air-cathode MFC containing carbon electrodes in the presence and absence of a polymeric proton exchange membrane (PEM). Bacteria present in domestic wastewater were used as the biocatalyst, and glucose and wastewater were tested as substrates. Power density was found to be much greater than typically reported for aqueous-cathode MFCs, reaching a maximum of 262 ± 10 mW/m2 (6.6 ± 0.3 mW/L; liquid volume) using glucose. Removing the PEM increased the maximum power density to 494 ± 21 mW/m2 (12.5 ± 0.5 mW/L). Coulombic efficiency was 40−55% with the PEM and 9−12% with the PEM removed, indicating substantial oxygen diffusion i...
1,833 citations
TL;DR: A critical review on the recent advances in MFC research with emphases on MFC configurations and performances is presented.
1,496 citations
TL;DR: In this paper, the key advances that will enable the use of exoelectrogenic microorganisms to generate biofuels, hydrogen gas, methane, and other valuable inorganic and organic chemicals are reviewed.
Abstract: Waste biomass is a cheap and relatively abundant source of electrons for microbes capable of producing electrical current outside the cell. Rapidly developing microbial electrochemical technologies, such as microbial fuel cells, are part of a diverse platform of future sustainable energy and chemical production technologies. We review the key advances that will enable the use of exoelectrogenic microorganisms to generate biofuels, hydrogen gas, methane, and other valuable inorganic and organic chemicals. Moreover, we examine the key challenges for implementing these systems and compare them to similar renewable energy technologies. Although commercial development is already underway in several different applications, ranging from wastewater treatment to industrial chemical production, further research is needed regarding efficiency, scalability, system lifetimes, and reliability.
1,469 citations
TL;DR: It is demonstrated here that it is also possible to produce electricity in a MFC from domestic wastewater, while at the same time accomplishing biological wastewater treatment (removal of chemical oxygen demand; COD), which may represent a completely new approach to wastewater treatment.
Abstract: Microbial fuel cells (MFCs) have been used to produce electricity from different compounds, including acetate, lactate, and glucose. We demonstrate here that it is also possible to produce electricity in a MFC from domestic wastewater, while atthe same time accomplishing biological wastewater treatment (removal of chemical oxygen demand; COD). Tests were conducted using a single chamber microbial fuel cell (SCMFC) containing eight graphite electrodes (anodes) and a single air cathode. The system was operated under continuous flow conditions with primary clarifier effluent obtained from a local wastewater treatment plant. The prototype SCMFC reactor generated electrical power (maximum of 26 mW m(-2)) while removing up to 80% of the COD of the wastewater. Power output was proportional to the hydraulic retention time over a range of 3-33 h and to the influent wastewater strength over a range of 50-220 mg/L of COD. Current generation was controlled primarily by the efficiency of the cathode. Optimal cathode performance was obtained by allowing passive air flow rather than forced air flow (4.5-5.5 L/min). The Coulombic efficiency of the system, based on COD removal and current generation, was < 12% indicating a substantial fraction of the organic matter was lost without current generation. Bioreactors based on power generation in MFCs may represent a completely new approach to wastewater treatment. If power generation in these systems can be increased, MFC technology may provide a new method to offset wastewater treatment plant operating costs, making advanced wastewater treatment more affordable for both developing and industrialized nations.
1,459 citations