Percolation modeling of foam generation in porous media
- Univ. of Texas, Austin, TX (United States). Dept. of Petroleum Engineering
A foam is a dispersion of a large volume of gas in a continuous liquid phase, stabilized by surfactant. Foams can improve sweep efficiency and oil recovery in gas-injection enhanced oil recovery projects. An important issue for these foam processes is the ease of foam generation in porous media. Previously, Rossen and Gauglitz (1990) derived a percolation model for foam generation in steady gas-liquid flow in porous media. More recent advances in percolation theory require modification of this model, as described in this note. Briefly, Rossen and Gauglitz assumed that the liquid films or lamellae present in foam block a randomly selected fraction (1 [minus] f) of the pore throats in the medium. Creating the large number of lamellae that define a foam from the relatively few present initially requires displacing these lamellae from their pore throats so they can multiply by the processes of lamella division and repeated snapoff. Displacing lamellae from pore throats to initiate the generation process requires imposing a pressure difference across the throat of order one or a few kPa (a few tenths of a psi). Generating'' foam, therefore, depends on lamella mobilization, which depends on the magnitude of the pressure drop [Delta]P across individual pore throats blocked by lamellae. Rossen and Gauglitz's model predicts that the minimum pressure gradient for foam generation [del]P[sup min] decreases nearly linearly, as f approaches f[sub c], the percolation threshold for the pore network, from either direction.
- OSTI ID:
- 7159190
- Journal Information:
- AIChE Journal (American Institute of Chemical Engineers); (United States), Vol. 40:6; ISSN 0001-1541
- Country of Publication:
- United States
- Language:
- English
Similar Records
MECHANISTIC STUDIES OF IMPROVED FOAM EOR PROCESSES
Gas-bubble snap-off under pressure driven flow in constricted noncircular capillaries