Efficacy of Dispersing Agents on Gradation of MSW Dumping Site Soils

Abstract

The diversified behavioral effects in permeability, compressibility, consolidation and shear strength of the soil is due to the particle sizes of the fine grained soils.  Thus, the analyses of the particle sizes of the soil are very important for any geotechnical problems. The dispersion characteristics of the Municipal Solid Waste (MSW) dump site soil with a series of dispersing agents of Sodium Tri Poly Phosphate (STPP), Disodium Oxalate (DO), Tri Sodium Pyro Phosphate (TSPP), Do-decayl Benzene Sulphonate (DDBS), Sodium Hexa Meta Phosphate (SHMP), Sodium Carbonate (SC) and Sodium Hydroxide (SH) are studied by using Hydrometer analyses method. The raw soil mass collected from the solid waste dumping site of Ariyalur town in Tamilnadu, India was prepared into a fine particles such that to have 90 ?m by various physical wash and grinding methods.The study shows that the addition of dispersing agent increases the interparticle repulsion among the soil particles and thereby decreases the tendency of particle flocculation during sedimentation. It has been observed that the compounds DDBS and SHMPare effectively improved the dispersing property of the soil and also it segregate the particle sizes as minimum of1?m without any increment in the acidity of the soil.  

Keywords: Soil particle gradation, Percentage of Finer particles, dispersing agents STTP,   TSPP, DDBS, SHMP, DO and SC, MSW Soil