T271 Characterizing, Predicting, and Managing Long-Term Contaminant Flux for Complex Subsurface Environments

Wednesday, 21 October 2009
1:30 PM - 5:30 PM
E141/142

THE IMPACT OF IMMISCIBLE DISPLACEMENT AND TRAPPED AIR ON PORE-SCALE FLUID CONFIGURATION FOR THREE-PHASE

Paper number: T271-1
Program: Technical Sessions
Time: 1:30 PM – 1:45 PM

Authors

Abstract

The objective of this study was to examine the impact of immiscible fluid displacement and trapped air on pore-scale distribution and morphology of organic liquid in natural porous media. High-resolution, three-dimensional images of an organic liquid (trichloroethene) in three-phase (water/organic-liquid/air) systems were obtained using synchrotron X-ray microtomography before and after water imbibition. A significant portion of the organic liquid in the three-phase system was observed to exist as lenses and films in contact with air. The presence of air had a significant impact on organic-liquid/water interfacial area. Upon imbibition, a fraction of the air phase was displaced downgradient. Concomitantly, the morphology of the organic-liquid blobs no longer in contact with air reverted to that characteristic of a two-phase distribution. This change in morphology resulted in a change in interfacial area. These results illustrate the malleable nature of fluid configuration under dynamic, multiphase flow conditions.