Analysis of selected heavy metals leaching from stabilized/solidified specimens containing rubber sludge waste treated using ordinary Portland cement and rice hush ash

Heavy metals bearing waste originate from biological rubber wastewater treatment plant has addressed a significant threat to the environment due to its leaching problem as waste comes in contact with water run-off during raining. Prolong cumulative pollution of heavy metals was unacceptable. As solution to this problem, a treatment of rubber sludge waste was performed using ordinary Portland cement and rice husk ash (via stabilisation/solidification technique) aimed to reduce the leaching of the selected heavy metals originated from the waste. The proposed treatment was purposely used to transform the waste from hazardous to non-hazardous material so that it can be safely disposed in a sanitary landfill. The objective of this study was to determine the leaching components and its pattern of treated sample later known as stabilised/solidified specimen. Findings from this study shows the leaching of selected heavy metals such as Iron (Fe), Calcium (Ca) and Magnesium (Mg) are fluctuated in general for each batch with declining pattern as the leaching duration increases. However, leaching of iron from the immersed stabilised/solidified (i.e. tank leaching) specimens of both control and sample batches were found to be above the Standard A Industrial Effluent permissible limit at 1 ppm of Fe.