Treatment of solid waste landfill leachate by electrochemical method and use of sewage sludge in geopolymer production

Solid waste landfills have been established in order to prevent the damage of domestic and industrial wastes to the environment. The biggest problem is the leachate that occurs in landfills. Since there are many inorganic and organic pollutants in the leachate, its treatment has enormous significance for the environment. In this study, the treatment of leachate was carried out by the electrocoagulation method, which is an electrochemical method using aluminum electrodes. Phosphorus and nitrogen removal, especially chemical oxygen demand (COD), were used as pollutant parameters. The efficiency of the electrocoagulation process was evaluated by considering the initial pH, current density, amount of supporting electrolyte and stirring speed parameters. Optimum initial pH value and optimum current density were determined. It was observed that the amount of supporting electrolyte and the removal of pollutants increased in direct proportion. In addition to the treatment efficiency in the experiments, energy consumption was also examined. The waste sludge formed at the end of the electrocoagulation process applied to the waste water was used in the production of geopolymers obtained by alkali activation of alumina silicate materials. Characterization tests were performed on the produced geopolymers using XRF, XRD, FTIR, ICP-MS, NMR and SEM-EDS devices. The obtained data show that the addition of waste sludge supports the formation of geopolymers.