Abstract
Studies of NAPL dissolution in porous media have demonstrated that measurement of saturation alone is insufficient to describe the rate of dissolution. Quantification of the NAPL-water interfacial area provides a measure of the expected area available for mass transfer and will likely be a primary determinant of NAPL removal efficiency. To measure the interfacial area, we have used a synchrotron-based CMT technique to obtain high-resolution 3D images of flow in a Soltrol-water glass bead system. The interfacial area is found to increase as the wetting phase saturation decreases, reach a maximum, and then decrease as the wetting phase saturation goes to zero. These results are compared to previous findings for an air-water-glass bead study; The Soltrol-water interfacial areas were found to peak at similar saturations as those measured for the air-water system (20-35% saturation range), however, the peak values were in some cases almost twice Lis high for the oil-water system. We believe that the observed differences between the air-water and oil-water systems to a large degree can be explained by the differences in interfacial tensions for the two systems.
Original language | English |
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Journal | Advances in Water Resources |
Volume | 29 |
Issue number | 2 |
Pages (from-to) | 227-238 |
ISSN | 0309-1708 |
Publication status | Published - 2006 |
Keywords
- capillary pressure-saturation curves
- Interfacial areas
- porous media
- NAPLs
- microtomography
- multi-phase flow