Simulation of Foam Transport in Porous Media

FOllin is an excellent fluid for achieving mobility control of gas in porous media. Practical application of fOllins for EOR processes, however requires a predictive model of foam displacement. Further, quantitative information on fOllin-flow behavior at reservoir flow rates llild pressures is required as input to llily field-scale modeling. An experimental and mechanistic-modeling study is reported for the transient flow of fOllin through 1.3 ,..lIn2 (1.3 D) Boise sandstone at backpressures in excess of 5 MPa (700 psi) over a quality range from 0.80 to 0.99. Total superficial velocities range from as little as 0.42 to 2.20 m/day (1.4 ftlday to 7 ft/day). Sequential pressure taps and gllimna-ray densitometry measure flow resistance and in-situ liquid saturations, respectively. We garner experimental pressure and saturation protiles in both the transient and steady states. Adoption of a mean-size foam-bubble conservation equation along with the traditional reservoir simulation equations allows mechanistic foam simulation. Since fOllin mobility depends heavily upon its texture, the bubble population balance is both useful and necessary as the role of fOllin texture must be incorporated into any model which seeks accurate prediction of flow properties. Our model employs capillary-pressure-dependent kinetic expressions for lamellae generation and coalescence and also a tenn for trapping of lllinellae. References and illustrations at end of paper 309 Additionally, the effects of surfactant chemical trmlspOlt moe included. We find quantitative agreement between experimental and theoretical saturation and pressure protiles in both the trmlsient and steady states.