HR: 1340h
AN: H33A-0450    [Abstracts]
TI: A Study of Oil-Water and Air-Water Interfacial Areas Measured Using Synchrotron-based CMT
AU: * Culligan, K A
EM: kculliga@nd.edu
AF: University of Notre Dame, Department of Civil Engineering , Notre Dame, IN 46556 United States
AU: Wildenschild, D
EM: wildend@geo.oregonstate.edu
AF: Oregon State Univeristy, Department of Geosciences, Corvallis, OR 97330 United States
AU: Christensen, B S
EM: brc@er.dtu.dk
AF: Technical University of Denmark, Environment and Resources, Lyngby, DK-2800 Denmark
AU: Gray, W G
EM: graywg@unc.edu
AF: University of North Carolina, Department of Environmental Science and Engineering, Chapel Hill, NC 27599 United States
AB: Studies of NAPL dissolution in porous media have demonstrated that the macroscale measurement of saturation alone is incapable of describing the rate of dissolution. Quantification of the NAPL-water interfacial area provides a measure of the expected area available for mass transfer between the phases 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 (17 micron voxels) 3D images of flow in a Soltrol-water-glass bead system. An array of image analysis techniques is used to compute the interfacial area, excluding the presence of films, which is found to increase as the wetting phase saturation decreases, reach a maximum, and then decrease as the wetting phase saturation goes to zero, supporting the findings of a previous air-water-glass bead study. These results are also supported by pore scale numerical studies presented in the literature. An REV analysis was conducted, demonstrating that the volume used was likely at the lower limits of an acceptable REV size for porosity, saturation, and wetting-non-wetting interfacial area. The wetted fraction of the solid surface was also measured and found to be a non-hysteretic function of the saturation.
DE: 1899 General or miscellaneous
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting