Research Article - Journal of Environmental Waste Management and Recycling (2021) Volume 4, Issue 3

Investigation of brewery wastewater as a potential of power generation and co-degradation of organic wastes using microbial bio-reactors (MFC): Case study for dashen brewery, Ethiopia

The demand for searching bio-energy resource with an efficient conversion system is increasing worldwide. Microbial Fuel Cell (MFC) systems represent a new promising and emerging technology that generates electricity satisfactorily while Co-reduction of the organic matter in wastewater. In terms of performance, only few methodologies availability and major pollutants loads of Brewery wastewater in the country Ethiopia were the inspirations of this study. The study aims investigation of brewery wastewater as a potential of generating electricity and Co-Treatment using microbial fuel cell system. A dual chamber microbial fuel cell system was assembled with graphite electrode as an anode and cathode with Nafion membrane for proton exchange, copper wire and different resistors were used.More importatntly The MFC with 4000, 3000, 2000, 1000 and 500 mg/L Chemical Oxygen Demand (COD) was inoculated with 150 ml mixed-culture of well-mixed sludge sample used anaerobically in the anode chamber (2.5 L). Potassium permanganate (KMnO4) at 0.3 M, 0.5 M and 0.8 M concentration was used aerobically as a final electron acceptor in the cathode chamber (2.5 L). Alternatively, instead of potassium permanganate, air was used in the cathode chamber as the final electron acceptor. The MFC bio electro-chemical batch process was operated for 20 days. Voltage and current generation were measured by digital voltmeter and ammeter. A maximum voltage of 1060 mV was obtained at 0. 5 M KMnO4 and 1000 mg/L COD on the 15th day. Taking polarization curve as a base line, the maximum power density and current density with 200 ? external resistor were 682.83 mW/m2 and 1.54 mA/cm2 respectively at 0.5 M KMnO4 and 1000 mg/L COD concentration. Increasing the Ohmic resistance decreased from the point of the maximum attainable power from 682.83 mW/m2 to 69.14 mW/m2. The current also decreased consistently with increasing of the resistance from 1.54 to 0.07 mA/cm2 at an external resistor of 5 k?. The chemical oxygen demand removal efficiency of MFC was found to be 45-67% at 0.5 M of KMnO4 and 21-34% when air was used as the electron acceptor. Maximum removal efficiency was obtained when potassium permanganate was used as the final electron acceptor in the cathode chamber. This research result demonstrated performance enhancement of producing electricity from brewery wastewater and co-reduction of the brewery waste at the same time with possible efficiency enhancement and reveals satisfactory results. Author(s): Tegen Dagnew*, Bassazin Ayalew, Tadele Assefa

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