Utilization of sugarcane BagAsse ash for stabilization/solidification of lead-contaminated soils

Abstract

Recently, many researchers are interested in using agricultural waste as an additive to remediate the contaminated soils. In this study, the effectiveness of sugarcane bagasse ash (SCBA) as the substitution binder to Ordinary Portlant Cement (OPC) content in Stabilization/Solidification (S/S) method was investigated through the physical and chemical characteristics namely the Unconfined Compressive Strength (UCS) and Toxicity Characteristic Leaching Procedure (TCLP). Synthetic contaminated soil was prepared in bulk by mixing soil samples with lead nitrate to achieve the concentration of 500 ppm. The OPC and SCBA varying from 5% to 20% were added to stabilize and solidify the contaminated soils. The cylindrical specimens (D = 38 mm, H = 76 mm), was compacted in five layers with 50 blows each. A further 3, 7, 14 and 28 days were allowed for curing in the temperature 25±2 ◦C and humidity > 80%. Results indicate that all samples containing OPC and SCBA satisfy the US EPA strength requirement of 0.35 MPa for S/S sample. The TCLP testing shows that sample containing OPC with SCBA has been successful treated which produced the leachability below US EPA limit for lead of 5 mg/L. In conclusion, the use of SCBA as part of replacement of OPC has been successful in increasing the strength and reducing the leachability compared to untreated sample.