Electrochemical Processes for Stabilized Landfill Leachate Treatment: A Brief Review

Stabilized leachate from the old landfill has caused major concern due to its toxic nature and poor biodegradability. Although their composition may vary in each region, the characteristics are similar, e.g., pH above 7, BOD5/COD ratio below 0.2, high ammoniacal nitrogen concentration, etc. In the last two decades, many studies have been conducted to search for the best alternative technology to treat this type of wastewater. The electrochemical process has gained more interest due to its effectiveness, simplicity, versatility, easy automation, less chemical consumption, and low sludge production. This technology typically utilizes a compact reactor; thus, it is suitable for a landfill with a space shortage. Moreover, integrating the biological process with electrochemical treatment can be a better option to increase treatment efficiency and minimize operational costs from energy consumption. This chapter briefly describes the electrochemical treatment, which focuses on the electrocoagulation, electro-Fenton, and electrochemical oxidation processes. The process mechanisms and crucial factors that may affect their performances are explained. Their performance and application were compiled as a single treatment, pre-treatment, or post-treatment. The advantages and limitations of each treatment were also summarized. The objective is to provide a useful reference for researchers to design a more effective and efficient treatment and help decision-makers select the most appropriate technology based on the process efficacy and cost-effectiveness.