Landfill Leachate Treatment by Direct Thermochemical Treatment

Abstract

Landfill leachate poses significant environmental and health risks due to its complex composition of organic and inorganic contaminants. This study evaluates a thermochemical treatment process to address the pollution caused by leachate, particularly in West Nusa Tenggara, where conventional landfill management has been insufficient. Despite advances in treatment technologies such as membrane filtration, biological methods, advanced oxidation processes, and adsorption, these methods often fall short against persistent and toxic compounds found in leachate. The thermochemical treatment, including the hydrothermal process, offers a promising alternative, capable of degrading complex molecules and reducing the volume and toxicity of effluent. Using a laboratory-scale hydrothermal process, this research examines the effect of treatment duration on leachate composition and the efficacy of pollutant removal. Prior to treatment, leachate samples were analyzed for COD, BOD, TSS, and heavy metals. The treatment process entailed heating the leachate at temperatures between 100–120°C for intervals ranging from 5 to 40 minutes. Results showed significant reductions in BOD, COD, and TSS, with a noticeable transformation in color from dark brown to nearly transparent. Heavy metals also exhibited a marked reduction, with the thermochemical process achieving over 90% efficiency, surpassing conventional treatments. The findings suggest that the thermochemical method, particularly the hydrothermal approach, is highly effective, warranting further research into its scalability and commercial viability as a robust leachate treatment solution.