Sustainable Approach for Leachate Treatment: Electricity Generation in Microbial Fuel Cell

Abstract

Electricity generation from landfill leachate was examined by using both a dual-chamber microbial fuel cell (MFC) and a single chamber MFC. Experimental results showed that the maximum power density of 2060.19 mW/m3 in the dual-chamber MFC and that of 6817.4 mW/m3 in the single chamber MFC were obtained. It was recognized that the difference in internal resistance for two MFC systems was the main reason for resulting in the difference of power generation. Power generation as function of chemical oxygen demand (COD) in single chamber MFC showed a Monod-type relationship with Pmax of 5920.96 mW/m3 and Ks of 251.39 mg/L at an external resistance of 500 Omega. Cyclic voltammetry showed that electrons were directly transferred onto the anode by bacteria in biofilms, rather than self-produced mediators of bacteria in the solutions. At low COD concentration, electricity generation was limited by the anode due to kinetic limitation; while at high COD concentration, the cathode was shown to have more significant effects on the electricity generation than the anode. COD in leachate could be removed when it increases, mainly because oxygen diffused from the cathode was substantially reduced by aerobic or anoxic bacteria in the anode chamber, leading to the substrate loss. Removal of ammonium-nitrogen was not observed in the single chamber MFC. This novel technology provides an economical route for electricity energy recovery in leachate treatment.

Energy generation in a Microbial Fuel Cell using anaerobic sludge from a wastewater treatment plant

“…Hence, 95 % of the substrate was not employed to generate electricity. According to You et al, (2006), low electron recovery efficiency could be due to improper selection of exoeletrogenic bacteria from a microbial community as a result of an inadequate culture medium or environmental conditions. This selection could involve appropriate control of the nutrients during MFC operation.…”

Biokinetic evaluation of fatty acids degradation in microbial fuel cell type bioreactors

“…Cathodic and anodic potentials were also measured occasionally against a Calomel reference electrode. To determine the MFC current and power, external loads in the range 1,000-6,000 ohms resistors [36] were applied during the biodegradation of organics. Sufficient time was given for the potential to stabilize.…”

Electricity generation from terephthalic acid using a microbial fuel cell

“…However, few studies involving high concentration organic wastewater as substrates have been reported. 16 The high concentration organic wastewater may provide high chemical energy compared with low COD biodegradable sanitary sewage. In principal, if suitable bacteria are directly used to catalyze the effective conversion of organic matter into electricity without the addition of mediators, a much higher power output can be obtained.…”