Heavy metals reduction using electrocoagulation in enhancing the water quality near unlined landfill: A case study

Abstract

Leachate contributes to the contamination of surface water, groundwater, and soils around the unlined landfill area. The dark-coloured liquid has an unpleasant smell which is produced when moisture percolates through the solid wastes. Heavy metals are among the hazardous contaminants from leachate. This research was done to determine the concentration of heavy metals samples taken at nearby surface water in Ampar Tenang landfill before and after the electrocoagulation process was conducted. It can be observed that the surface water near the landfill site has been contaminated with cadmium, iron, and lead. From the results obtained, the value of cadmium was 0.015 mg/L while the standard set by the Department of Environment (DOE), Malaysia is 0.001 mg/L. Iron has a greater value, 3.81 mg/L, than the standard allowed, which is 1.0 mg/L. The concentration of lead was 0.06 mg/L, which is above the standard of 0.01 mg/L. After 3 hours of electrocoagulation treatment, the process managed to remove 40% of cadmium, 76% of iron and 81% of lead. The final concentrations of cadmium, iron and lead were 0.009, 0.92 and 0.011 mg/L. It can be concluded that electrocoagulation is efficient in removing heavy metals in the contaminated water.