Abstract

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Many vital industries discharge toxic heavy metal sludges into their waste streams The traditional concept of dumping of the hazardous waste is no longer valid because of their possible return to the environment and entering in to the food chain. In this context fixation or immobilization of toxic waste in a solid crystalline or polymeric matrix is important so that the monolithic solid mass thus obtained can be safely handled, transported and disposed off using well established methods of land filling and burial. The use of man made materials of low permeability to line the waste storage disposal has been demonstrated to be feasible method of preventing leach ate and toxic components from seeping out of waste impoundment and polluting the ground. water. A great array of materials including fine grain soils, clays and polymeric material are potential candidates for use as coatings or liners.The present paper deals with leaching of heavy metals in solidified waste coated with polyurethane coating.

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