MODEL FOR IN-SITU AIR STRIPPING OF CONTAMINATED SOILS - EFFECTS OF HYDROCARBON ADSORPTION

Air stripping as a means of soil remediation has gained popularity in recent years. In this in situ process, clean air is injected into the contaminated soil zone to volatilize and strip the contaminants, which are then removed by the carrier gas. The process has been found to be effective especially for treating the vadose zone of the soil contami nated with volatile and semivolatile organics. Nitrogen adsorption/des orption experiments in this study were performed on a soil sample to e stablish its desorption characteristics. A field-scale model for the a ir stripping process has been developed to simulate the removal of sem ivolatile hydrocarbons. The numerical results show that the interphase contaminant transport from the sorbed to the vapor phase plays a domi nant role in influencing the process effectiveness.