کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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6355317 | 1315041 | 2013 | 7 صفحه PDF | دانلود رایگان |
Three natural clayey soils from Tunisia were studied to assess their suitability for use as a liner for an acid waste disposal site. An investigation of the effect of the mineral composition and mechanical compaction on the hydraulic conductivity and fluoride and phosphate removal of three different soils is presented. The hydraulic conductivity of these three natural soils are 8.5Â ÃÂ 10â10, 2.08Â ÃÂ 10â9 and 6.8Â ÃÂ 10â10Â m/s for soil-1, soil-2 and soil-3, respectively. Soil specimens were compacted under various compaction strains in order to obtain three wet densities (1850, 1950 and 2050Â kg/m3). In this condition, the hydraulic conductivity (k) was reduced with increasing density of sample for all soils. The test results of hydraulic conductivity at long-term (>200Â days) using acidic waste solution (pHÂ =Â 2.7, charged with fluoride and phosphate ions) shows a decrease in k with time only for natural soil-1 and soil-2. However, the specimens of soil-2 compressed to the two highest densities (1950 and 2050Â kg/m3) are cracked after 60 and 20Â days, respectively, of hydraulic conductivity testing. This damage is the result of a continued increase in the internal stress due to the swelling and to the effect of aggressive wastewater. The analysis of anions shows that the retention of fluoride is higher compared to phosphate and soil-1 has the highest sorption capacity.
⺠Examined the hydraulic conductivity evolution as function of dry density of Tunisian clay soil. ⺠Follow the hydraulic conductivity evolution at long-term of three clay materials using the waste solution (pH=2.7). ⺠Determined how compaction affects the hydraulic conductivity of clay soils. ⺠Analyzed the concentration of F and P and examined the retention of each soil.
Journal: Waste Management - Volume 33, Issue 1, January 2013, Pages 60-66