Leachate Characterisation and Heavy Metal Removal by Clay-Pressmud Batch Equilirium Study

Abstract

Leachate contents from the landfill that infiltrate the liner may contaminate nearby groundwater and river. Hence, the liner material must be chosen properly so that pollutants can be retained as much as possible at the liner thus reducing the contamination risk. This study studied the characteristics of earthenware clay and pressmud, and their suitability in reducing heavy metals content in leachate. Their suitability to fit as candidate for a landfill liner was tested using batch equilibrium study at 24 and 48 hours reaction times. The mixture of clay and pressmud were labelled PM0, PM10, PM30, PM50, PM80 and PM100 based on their pressmud content. Both reaction time, in any mixtures, manganese easily removed from leachate. 97% zinc was reduced in PM80 after 48 hours reaction time. No significant removal detected for lead in PM0, PM50 and PM80 although the experiment was prolonged from 24 to 48 hours. In a nutshell, for overall contaminants, the longer the reaction time, the higher removal percentage. The clay-pressmud mixtures have the potential to be applied as a landfill liner, however, the removal percentage of metal ions depends on mixture’s physicochemical characteristic.