Microbial Fuel Cell for the Recovery of Sludge from the Treatment of Effluents by Electrocoagulation

The micro-organisms present in the domestic effluents allowed the formation of an electroactive biofilm by oxidation of the organic matter on the surface of a carbon fabric anode, in a microbial fuel cell (MFC). Previous studies have demonstrated the effectiveness of the electrocoagulation process for the treatment of industrial effluents. During treatment, the metal hydroxide sludge formed adsorbs pollutants. These sludges could be recovered through their use as fuel in a microbial fuel cell. The cell was inoculated with sludge from tests on effluents taken from a wastewater treatment plant. The results showed a decrease in chemical oxygen demand by 90.27%, dissolved oxygen by 75% and turbidity by 72%. Analysis of the sludge from this treatment showed the presence of sulphite-reducing coliforms and clostridium which oxidize the organic matter contained in a substrate enriched with acetate or glucose. The maximum power densities obtained are 41.29 mW/m2 with acetate and 27.57 mW/m2 with glucose respectively. The study was carried out on a microbial fuel cell with two compartments separated by an ion exchange membrane.