Attenuative Capacity of Compacted Bagasse Ash Treated Foundry Sand

Physical and chemical as well as batch adsorption and column tests were carried out on foundry sand treated with up to 8% bagasse ash and compacted with British Standard heavy (BSH) energy. Specimens were permeated with solid waste (MSW) leachate sourced from a waste landfill. Batch equilibrium studies carried out on five foundry sand - bagasse ash mixtures prepared at stepped bagasse ash treatments of 0, 2, 4, 6 and 8% by dry weight of soil in a 1:4 foundry sand-solution ratio were used to assess the adsorption of ions present in the municipal solid waste leachate. Tests results show trends of chemical sorption by the foundry sand-bagasse ash mixtures in the order sodium, potassium, calcium and magnesium (NaP+P> KP+P> CaP2+P > MgP2+P). Higher bagasse ash treatment of foundry sand recorded higher retardation factors and lower diffusion coefficients with an increased sorption of the contaminant species. In general, higher bagasse ash treatment of foundry sand has significant advantages over the untreated foundry sand and will better serve as landfill liner material