Dealing with LNAPL polluted sites and use of air sparging as a treatment option

摘要

This paper presents a formula that describes the formation of bubbling air channels during injection of air into a porous medium beneath the groundwater level on a pore scale. To derive the formula, mathematical descriptions of several processes are combined. The formula equals the air pressure within the air pocket that has been formed around the air injection point, to the pressure needed for the air to flow through a pore with a certain radius. In this way, the number of channels formed in the porous media is determined by its pore size distribution, depending on the rate of injection. Because of the importance of pore size distribution, the process of air injection should in fact be modelled at pore scale. To overcome this problem, a relationship should be found between air saturations resulting from modelling and air distribution following from the formula presented here.