Remediation of Simulated Soils Contaminated with Diesel

Abstract

Soil venting has been shown to be an effective method to remediate soils contaminated with hydrocarbons. In this study diesel fuel was used as the only contaminant and several one-dimensional experiments were conducted to investigate the effects of preheating the air in a soil venting system at two different flow rates and inlet air temperatures. Temperature readings of thermocouples located in the test section of the experimental setup were recorded during the experiments. The effluent gas samples were extracted at selected times and analyzed with the help of a gas chromatography system. The experimental results were also used to validate the model of Lingineni and Dhir for diesel fuel. The model includes energy balance and conservation of mass equations as well as diffusional resistance experienced by various species in the liquid phase. In exercising the model, diesel fuel was subdivided into five components. The experimental results show that the diesel fuel components were removed according to their volatility, with the higher volatility components being removed first. It was found that preheating the venting air, as well as increasing the venting air flow rate, can significantly increase the removal rates of the diesel fuel components. The measured temperatures and removal rates of diesel components have been found to be in good agreement with the predictions from the model. For a 22-cm-tall and 11.4-cm-diameter test section, in which the flow rate varied from 0.396 m