Potential of Silty Clay Soil as an Attenuation Material for Containment of Phenolic Wastewater Outfall Site

Abstract

Use of compacted silty clay soil collected from the Gangetic river sediment near Kolkata, West Bengal, India has been experimentally explored in the laboratory as a low cost landfill liner material for retarding the migration of phenolic compounds releasing from a coke oven wastewater outfall site in Durgapur, West Bengal, India. The phenol concentration in the wastewater was found in the range of 4.0-12.0 mg/L in different times of a calendar year. Batch adsorption results reveal that the maximum phenol removal efficiency of 95% was achieved at an initial phenol concentration of 4 mg/L for the soil dose of 20 g/L, solution pH of 6.0 and after a reaction time of 24 h. Index properties, swelling potential, compaction characteristics and permeability of the soil indicate that it is low compressible, moderately expansive and low permeable (1.90×10-8 cm/s) and having reasonably good phenol attenuation capacity (472.5 mg/g). These favorable findings suggest that the compacted clay soil can be potentially utilized as primary landfill liner material for containment of phenolic waste generated from coke oven wastewater.