Characteristics of landfill leachate and leachate treatment by biological and advanced coagulation process: Feasibility and effectiveness – An overview

This review thoroughly assesses the viability and effectiveness of biological and advanced coagulation methods for treating leachate. It offers a comprehensive analysis of landfill leachate, with a specific focus on its composition and the presence of diverse pollutants and contaminants. The study investigates leachate toxicity and evaluates advanced coagulation processes and strategies designed to remove or reduce organic contaminants by employing coagulants. The novelty of this review lies in its emphasis on demonstrating the efficacy of coagulation and flocculation methods utilizing chemicals such as alum, ferric chloride, and aluminum sulfate in leachate treatment. These methods facilitate the removal of recalcitrant pollutants and demonstrate considerable removal efficiency. Noteworthy removal effectiveness is evident in coagulation/flocculation procedures targeting various contaminants, including suspended particles, heavy metals, and xenobiotic organic compounds. Additionally, the study examines the leachate's toxicity both before and after treatment with the coagulation process.