Estimation of cleanup time for continuous and pulsed soil vapor extraction

Abstract

Soil vapor extraction (SVE) is a standard remediation technique for removing volatile organic compounds from contaminated soils. An important aspect in planning of SVE systems is the estimation of the time frame in which remediation can be achieved. In this study, analytical solutions are developed which can be used on the one hand for estimation of the required cleanup time and on the other hand for gaining insight into the processes which take place during the soil remediation. The analytical solutions are based on the well-mixed reservoir model as well as on the pure advective gas transport model, and their reliability is assessed by comparing their results with those of numerical simulations. Concerning mass transfer between the water phase and the solid phase, equilibrium as well as rate-limited sorption are considered. For the case of rate-limited sorption two extraction strategies (continuous extraction and pulsed extraction) are investigated.