EXPERIMENTAL STUDY ON THE MEASUREMENT OF S-p RELATIONS OF LNAPL IN A POROUS MEDIUM

A simple and effective device for measuring saturation-capillary pressure relation (S-p relation) in LNAPL-water system is designed with electrical conductivity probes, hydrophilic tensiometers and hydrophobic tensiometers. With this device, the S-p relation in LNAPL-water system is characterized. The S-p relation in air-LNAPL system is obtained by a scaling factor method. At a given saturation of wetting phase, it is found that the descending sequence of capillary pressures is in the order of air-water, LNAPL-water and air-LNAPL systems. The descending sequence of entry pressure and displacement pressure is also in the order of air-water, LNAPL-water and air-LNAPL systems. Furthermore, the relative permeability of air is larger than the LNAPL in their corresponding aqueous two phase systems, and the relative permeability of the LNAPL is slightly larger than water in their corresponding gaseous two phase systems.