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.

Advances in microbial fuel cells for wastewater treatment

Every year the pulp and paper industry consumes billions of metres cubed of water and produces huge amounts of highly polluted wastewater that needs to be treated. Conventional techniques of wastewater treatment require a high energy input and their environmental impact is debatable. Thus, the need to find new sustainable, environmentally friendly and efficient treatment techniques is urgent. Microbial fuel cells (MFC) are the technology of the future since they simultaneously treat wastewater and produce clean energy. The historical development of this technology towards its application to wastewater treatment was described. The application of MFCs in pulp and paper wastewater treatment is a new and developing field of investigation that still needs to overcome many limitations before its use on an industrial scale. This article reviews the limits of conventional treatment methods and the current state of the art MFC systems for pulp and paper wastewater treatment. The paper provides an overview of the electrogenic microorganisms able to produce electricity from pulp and paper wastewater. The bacteria, isolated at different stages of pulp and papermaking, are best suited for electrogenic activity in harsh environments. It was shown that MFC technology fully meets the requirements of sustainable pulp and paper wastewater treatment and, in terms of the input-output energy balance, remains energetically and environmentally competitive when compared to conventional treatment methods.

Limits and perspectives of pulp and paper industry wastewater treatment – A review

Bio-catalyzed electrochemical treatment of real field dairy wastewater with simultaneous power generation

Single chamber microbial fuel cell with spiral anode for dairy wastewater treatment

Due to depletion of fossil fuel and rapid industrial development there is urgent need to find environment friendly and sustainable technology for alternative energy. Microbial fuel cells (MFCs) are considered as a promising technology to extract energy from different sources and turn them into electricity. However, due to practical limitations, MFCs are still unsuitable for high energy demands. Since waste water contains several organic substances, therefore, production of electrical energy from waste water using MFC can offer an economical solution to the problem of environment pollution and energy crisis in near future. Therefore, the technological development for bioelectricity generation from waste water is becoming commercially worthwhile. In this review, discussion has been made critically on overall performance improvement strategies of microbial fuel cells and its application on waste water treatment along with effective power generation. The extensive research work has been carried out on microorganism selection, suitable MFC designs, appropriate electrode materials and optimum level of process parameters which would accelerate commercialization of this technology in near future. Therefore, this review has critically addressed the issues including usefulness of various cultures and their maintenance, applicability of different mode of operation and effectiveness of various MFCs to achieve sustainable power generation from waste water. In addition the various strategies for cost effective bioelectricity generation from waste water including novel reactor design as well as simultaneous treatment strategies have also been critically reviewed.

Performance improvement of microbial fuel cells for waste water treatment along with value addition: A review on past achievements and recent perspectives

Microbial fuel cell technology is a new type of renewable and sustainable technology for electricity generation since it recovers energy from renewable materials that can be difficult to dispose of, such as organic wastes and wastewaters. In the present contribution we demonstrated electricity production by beer brewery wastewater, sugar industry wastewater, dairy wastewater, municipal wastewater and paper industry wastewater. Up to 14.92 mA current and 90.23% COD removal was achieved in 10 days of operation.

Keywords: Bioelectricity, COD, Microbial Fuel Cells, Wastewater

Received: 12 November 2009 / Received in revised form: 30 November 2009, Accepted: 30 November 2009, Published online: 10 March 2010

Bioelectricity production from various wastewaters through microbial fuel cell technology

Renewable energy is an increasing need in our society. Microbial fuel cell (MFC) technology represents a new form of renewable energy by generating electricity from what would otherwise be considered waste. It is possible to directly generate electricity-using bacteria while accomplishing wastewater treatment in processes based on microbial fuel cell technologies. When bacteria oxidize a substrate, they remove electrons. Electric current generation is made possible by keeping bacteria separated from oxygen, but allowing the bacteria growing on an anode to transfer electrons to the counter electrode (cathode) that is exposed to air. In this report, the cellulosic waste was utilized for the bioelectricity production by Clostridium acetobutylicum and Clostridium thermohydrosulfuricum.

Bioelectricity production from paper industry waste using a microbial fuel cell by Clostridium species

Meniscal tissue engineering via 3D printed PLA monolith with carbohydrate based self-healing interpenetrating network hydrogel

Recent trends in biodegradable polyester nanomaterials for cancer therapy.

Bone marrow mesenchymal stem cells are an ideal candidate for bone tissue engineering due to their osteogenic potential. Along with chemical, mechanical signals such as fluid shear stress have been found to influence their differentiation characteristics. But the range of fluid shear experienced in vivo is too wide and difficult to generate in a single device. We have designed a microfluidic device that could generate four orders of shear stresses on adherent cells. This was achieved using a unique hydraulic resistance combination and linear optimization to the lesser total length of the circuit, making the device compact and yet generating four logarithmically increasing shear stresses. Numerical simulation depicts that, at an inlet velocity of 160 μl/min, our device generated shear stresses from 1.03 Pa to 1.09 mPa. In this condition, we successfully cultured primary rat bone marrow mesenchymal stem cells (rBMSCs) in the device for a prolonged period of time in the incubator environment (four days). Higher cell proliferation rate was observed in the intermittent flow at 1.09 mPa. At 10 mPa, both upregulation of osteogenic genes and higher alkaline phosphatase activity were observed. These results suggest that the intermittent shear of the order of 10 mPa can competently enhance osteogenic differentiation of rBMSCs compared to static culture.

Vineeta Sharma

Papers

Bioelectricity production from various wastewaters through microbial fuel cell technology

Bioelectricity production from paper industry waste using a microbial fuel cell by Clostridium species

Meniscal tissue engineering via 3D printed PLA monolith with carbohydrate based self-healing interpenetrating network hydrogel

Recent trends in biodegradable polyester nanomaterials for cancer therapy.

Low intermittent flow promotes rat mesenchymal stem cell differentiation in logarithmic fluid shear device