Treatment of landfill leachate by electrochemicals using aluminum electrodes

Abstract

Electrochemical oxidation process has been shown to be a favourable choice for Chemical oxygen demand (COD) and color removals from various types of wastewaters. The technique was employed for mineralization of semi-aerobic landfill leachate. Leachate sampling were carried out from Pulau Burung Landfill Site (PBLS), Penang, Malaysia. The main objective was to determine the effectiveness of electrochemical oxidation in leachate treatment using aluminum electrodes which are relatively nontoxic and cost-effective. The influence of pH, reaction time, current density, electrolyte concentration, agitation rate and dilution on COD and color removals was investigated. The highest COD and color removal were obtained as 57.1% and 72.0% respectively at pH 8, current density 60 mA/cm2, electrolyte concentration 2000 mg/L, agitation rate 400 rpm, dilution 50% and reaction time 4 h. The energy consumption was determined as 128 kWh/m3 for this type of landfill leachate. The study shows that electrochemical oxidation can be used as a step of shared treatment.