Batch Equilibrium Analysis of Compacted Cement Kiln Dust Treated Lateritic Soil

A series of physical and chemical (as well as batch adsorption) tests were carried out on compacted residual lateritic soil treated with up to 10 % cement kiln dust (CKD), an industrial waste, to evaluate the attenuative capacity of the mixture when used as a liner material. Batch adsorption tests were carried out to determine the sorption capacities of CKD-treated lateritic soil. Specimens were prepared at stepped CKD concentrations of0, 2.5, 5.0, 7.5 and 10.0 % by dry weight of soil in a 1:4 lateritic soil-solution ratio. Assessments of the adsorption of ions present in the municipal solid waste leachates used were carried out. Tests results gave trends of chemical sorption by the lateritic soil - cement kiln dust mixtures in the order, potassium, calcium and sodium (i.e., K⁺ > Ca²⁺> Na⁺). A 2.5 % CKD treatment of lateritic soil recorded peak retardation factor and increased sorption of the selected contaminant species. In general, CKD treatment of lateritic soil, which is a beneficial disposal of an industrial waste, has significant advantages over the untreated lateritic soil and, therefore, can be used as landfill liner material.