Analysis of lead (Pb) leaching from stabilized/solidified sample containing rubber sludge waste treated using ordinary Portland cement and rice husk ash

Lead (Pb) contaminated sludge originating from industrial rubber wastewater treatment has become a serious problem if been direct disposed in landfill. Lead has been recognized as harmful toxic heavy metals and capable to cause carcinogenic effect to human and other living creatures. The leaching of Pb from this waste can leads to more severe environmental problem associated with the contribution by water run-off, groundwater and surface water contaminations. An attempt to treat the rubber sludge using ordinary Portland cement and rice husk ash using stabilization/solidification technique has been performed in this study. Objective of this study is to evaluate the effectiveness of ordinary Portland cement and rice husk ash mixtures in reducing the leachability of lead in stabilized/solidified specimen. Based on the findings, it is revealed that lead from leaching of sample batches prepared (i.e. OWR1, OWR2 and OWR3) have successfully reduced as compared to the control batches. The combination of ordinary Portland cement and rice husk ash were proven to reduce the leaching of lead into the leachant closed to acceptable limit which was at 15?ppm.