Treatment of Leachates of a Controlled Landfill in Veracruz By Using the Fenton Method

摘要

Leachates are formed by the decomposition of solid waste contained in the final disposal site from liquids formed by precipitation or humidity in the area. Which, when filtered through waste, entrain substances in dissolved form and/or in suspension, creating a dark coloured liquid of variable characteristics and difficult to degrade, leading to contamination of soil and water bodies. Due to its variable characteristics, typical treatments such as evaporation, U.V. or recirculation are not suitable as chemical treatments. The Fenton process, being an advanced oxidation technique, has shown optimal performance in the treatment of young and mature leachates. Different parameters were tested during the Fenton oxidation-reduction process, which is consisted of treating the leachate with different combinations of hydrogen peroxide (H2O2) and ferrous sulphate (FeSO4) under different acidic conditions, determining the optimal pH values, and doses of the Fenton reagent. Optimal conditions of the oxidation process were: contact time 1 hour, a pH value equal to 2, H2O2 concentrations of 250 mg/L and 75 mg/L of Fe+2. The percentage of removal measured as BOD was of 96% at a final pH of 1.8.