TREATMENT OF SOME METAL IONS IN LEACHATE IN COMPACTED AND CONSOLIDATED CLAYS AND VARIABILITY PERMEABILITY

Abstract

In solid waste materials landfill sites leachate is the most significant problem in terms of environmental pollution. It is essential to block leachate before it reaches saturated layer or ground water level. To prevent this storage soil is made impermeable. Natural and crumpled clay used in sanitary landfill areas is usually used as ceiling or floor cover or in formation of side banks. Clay soil layers are employed effectively in blocking polluters such as leachate and organic liquids. According to previous researches the structure of soil is destroyed due to the leachate through and thus there have been alterations in permeability of the soil. This study has determined variations in the permeability of clay soil and removal rate of present ions in leachate on the clay soil. For this purpose, leachate, collected from Sanitary Landfill at Sile - Komurcuoda in Istanbul, was subjected to compaction via standard methods of compacted clay sample used in the same facility. It passed through consolidated reaction and thus the experimental permeability of samples was determined. In order to detect removal rate of clay, soil alterations of Fe(II), Zn(II), Cu(II), Pb(II) ions in influent and effluent of reactor have been analyzed. As a result of permeabilty experiments conducted with leachate, permeability alterations have been observed in clay soils to which standard compaction is apllied and clay soils to which compaction and consolidations are applied together. Pores between particules at clay soil to which standard compaction is applied is less than the pores between the particules on the clay soil to which standard compaction and consolidation are applied due to compression. When the results of clay soil permeability experiments are analyzed, existence of solid particules and microorganisms in the leachate at the beginning lead to dicrease of permeability, however, it has been observed that by the time being the permeability increases on account of deformations that the leachate causes on the clay soil. In general, when examining the experimental results of Fe(II), Mn(II), Zn(II), Cu(II), Pb(II) parameters, the removal rate of clay soil, compressed with standard methods and consolidated, was higher than that of clay soil that was compressed by standard compaction method.