Effectiveness of stabilization and solidification technique in remediation a clay soil contaminated with phenanthrene

Abstract

This article presents a study on the stabilization and solidification (S/S) of a clay soil contaminated with phenanthrene. Portland cement (PC) with percentages of 5%, 10%, 20%, and 30% was used for the stabilization and solidification (S/S) of the soil. Unconfined compressive strength (UCS) and leaching tests, and scanning electron microscopy (SEM) analysis were conducted to determine the effect of the binder on the remediation of the contaminated soil. The results indicated that both the percentage of PC and curing time are effective on the UCS and leaching behavior of the soil. With 5% PC, the reduction in the concentration of phenanthrene in the leaching tests was 47.7%, 70.0%, and 88.2% for curing times of 7, 14, and 28 days, respectively, in comparison with 68.7%, 88.3%, and 95.3% for 30% PC. Experimental data were analyzed by the ANOVA method. The results showed that both the percentage of cement and curing time have a significant effect on the concentration of phenanthrene during leaching. Sensitivity analysis showed that the effects of the percentage of PC and curing time were 21.82% and 78.18%, respectively, indicating that the curing time is more effective in reducing the concentration of phenanthrene than the percentage of PC.