title: Determination of Water-Oil Interfacial Area during 3-Phase Gravity Drainage in Porous Media.
abstract: Water-oil interfacial area in porous media was determined in laboratory experiments using sand columns consisting of either 2 (water and oil) or 3 (water, oil, and air) fluid phases. Surfactant sorption at the water-oil interface was directly measured for a wide range of water, oil, and air saturations undergoing gravity drainage. Differing values of the water-oil interfacial tension were also examined. The Gibbs adsorption equation was then used to obtain values for the water-oil interfacial area. Both 2- and 3-phase water-oil experiments showed a linear increase in interfacial area with decreasing water saturation. Results also showed that interfacial areas were not affected by changes in interfacial tension. The interfacial areas in the 3-phase experiments were less than half the calculated values of the corresponding 2-phase experiments, which contradicts predictions from a conventional pore level analysis of 3-phase flow. Copyright 2000 Academic Press.
authors.affiliation: Department of Petroleum Engineering, Stanford University, 367 Panama Street, Room 65, Stanford, California, 94305-2220
authors.initials: CE
authors.lastname: Schaefer
authors.initials: DA
authors.lastname: DiCarlo
authors.initials: MJ
authors.lastname: Blunt