VARIATION OF PERMEABILITY OF CLAY SOILS WITH DIFFERENT CONDITIONS PERMEATED WITH LEACHATE

Abstract

Solid waste landfills are a major problem and causes significant threat to groundwater and surface water. Municipal solid waste (MSW) is also a major problem in Turkey, as in many other countries. Istanbul, with a population of 14.2 million, is the crowded city in Turkey and approximately 14,000 tonnes of MSW are collected daily. In this study, the effects of leachates on permeability and the treatment capability of clay soils with different conditions (the natural clay, compacted clay, compacted and consolidated clay soil, compacted clay soil with nanomaterial's) have been investigated. Clay soil samples and leachate were obtained from the Sile-KomiIrctioda landfill area on the Asian side of Istanbul. In the experimental studies, standard proctor compaction tests and consolidation tests were applied to the clay soil. In addition, the permeability of the clay soil has been investigated by adding nano material's to the clay soil compacted by the standard method. The nanomaterial obtained from Erzurum oltu clay was used. The soil samples have a permeability k between 1.10(-6)-1.10(-9) m/s. In order to determine the removal rate and permeability of clay soils with different conditions and COD, SS are measured in the influent and effluent of the lab-scale reactor. It is concluded that in the beginning some decrease has been observed in permeability of the clay soil, associated with the contamination. In the beginning, a decrease in the permeability caused by the suspended solid matters in the leachate filling the spaces between the particles of the clay soil pores. After some time, these results show that leachates may cause increase in the permeability. The treatment capabilities of natural clay, compacted clay, compacted and consolidated clay soil, compacted clay soil with nanomaterials samples were quite high. The highest removal rates and the lowest permeability are obtained in natural clay, compacted clay soil with nanomaterials, compacted and consolidated clay, compacted clay, respectively.