Evaluating the efficiency of electrochemical process in removing COD and NH4-N from landfill leachate

Landfilling leachate contains a high concentration of organic and inorganic pollutants. The present study was aimed to evaluate the efficiency of the electrocoagulation system in removing chemical oxygen demand (COD) and ammonia-nitrogen (NH4-N) from leachate. The paper investigated the factors affecting removal efficiency such as current density (187.5, 375, and 562.5 A/m(2)), electrode material (Al and Fe), and electrolysis time and pH of the solution (6.5 +/- 0. 2). The results indicated that, in optimum conditions, the highest COD and NH4-N removal efficiencies were 66 and 63%, respectively. According to the results, performance of the Al electrode was better than that of the Fe electrode in terms of COD and NH4-N removal. Therefore, the results showed that electrocoagulation can be applied for the leachate pretreatment as a feasible and reliable technique.