Mineral Industries Research Center, Shahid Bahonar University of Kerman, Iran
Department of Chemical and Polymer Engineering, Faculty of Engineering, Yazd University, Yazd, Iran
This research work demonstrates the feasibility of accelerating bioremediation of a clay soil by supplementing with (NH4)2SO4, KH2PO4, sucrose (as an inducer for growth) and tween 80. The soil contained 7% residual gasoil. The bioremediation was stimulated by moisture adjustment to 10%, and inoculating with hydrocarbon degrading microorganisms. (NH4)2SO4 and KH2PO4 were added to the soil to obtain soil samples with C:N:P ratios of 100:1.4:1.4, 100:6.4:1.9, 100:11.4:2.4, and 100:21.4:3.4. The C:N:P of 100:11.4:2.4 resulted in more than 78% gasoil removal for duration of two months. Tween 80, in the range of 0-20mL/ (kg soil), was added to the soil samples with C:N:P ratio of 100:1.4:1.4. More than 84% removal was achieved when 10 mL/kg tween 80 was added to the soil. Sucrose, in the range of 0-20 g/(kg soil), was added to the soil samples with the C:N:P ratio of 100:1.4:1.4. For the sucrose level of 20 g/(kg soil), 79% removal was obtained in two months. Additional experiment was also conducted at two porosity levels of 54% and 22%. The removal percentage in the soil with high porosity was almost twice as compared to soil with low porosity.