TREATMENT OF STABILIZED LANDFILL LEACHATE BY PHYSICOCHEMICAL AND BIOOXIDATION PROCESSES

In this work the treatment of leachate originating from an old landfil l was compared using a variety of methods both singularly and in combi nation. Aerobic biological treatment gave a COD removal ranging from 3 2-35%, but it was very effective for BOD and ammonia removal (97% and 99%, respectively). By using chemical oxidation a COD reduction up to 33% was achieved. The application of chemical precipitation gave a COD removal in the range of 36-42%. The combination of biological and che mical oxidation, biological oxidation and chemical precipitation or ch emical oxidation and chemical precipitation, led to a COD reduction up to 57%. The best results were obtained when a biological oxidation wa s applied in two stages combination with chemical oxidation and chemic al precipitation reducing COD concentration values up to 87%.