Correlation Between Pore Structure of Sandstones and Tertiary Oil Recovery

1979

Interfacial Effects in the Displacement of Residual Oil by FoamA qualitative theory is developed to explain the roles of surface tension and the two surface viscosities in the displacement of foams through porous media. There is a critical value of the surface tension above which a foam cannot be displaced under a given pressure gradient. The displacement efficiency of a foam can be raised by increasing the surface tension to only slightly less than this critical value, by increasing the viscosity of the aqueous surfactant solution from which the foam is formed and by increasing the surface viscosities. These predictions are in agreement with available experimental data.

Section: Conclusion and Significancementioning

confidence: 77%

Section: Critical Value For Interfacial Tensionmentioning

confidence: 92%

Interfacial effects in the displacement of residual oil by foam

1979

“…Let p[$, be the equilibrium concentration of surfactant in phase 1 in the limit N , -0. We will mume that p[$ = 0.01 g/cm3, the diffusion coefficient for surfactant within phase 1 is crnz/s, R* = 10 pm (Batra and Dullien, 1973) …”

Section: Appendix A: Effect Of Interfacial Tension Gradientsmentioning

confidence: 99%

Effect of interfacial viscosities upon displacement in capillaries with special application to tertiary oil recovery

Giordano

1983

Turpin, J. L., and R. L. Huntington, "Prediction of pressure drop for twephase two-component concurrent flow in packed beds," AIChE J., 13,1196 (1967).Van Landeghem, H., "Multiphase reactors: Mass transfer and modelling," Chem. Eng. Sci., 35,1912Sci., 35, (1980. Weekman, Jr., V. W., and E. Myers, "Fluid flow characteristics of concurrent gas-liquid flow in packed beds," AIChE J., 10,951 (1964). Wen, C. Y., O'Brien, and L. T. Fan, "Pressure drop through packed beds operated cocurrently," J. interfacial viscosities, interfacial tension, and wetting during displacement in a single, cylindrical capillary. The effect of the interfacial viscosities is to increase the resistance to displacement regardless of the wetting condition. The predictions of a prior qualitative theory for the relative effects of the interfacial viscosities and of interfacial tension during tertiary oil recovery are fully supported by this analysis. This discussion further indicates that the interfacial dilatational viscosity may be relatively more important than the interfacial shear viscosity.

“…The measurements of Stoodt and Slattery (1984) suggest that the interfacial dilatational viscosity may be two orders of magnitude larger than the interfacial shear viscosity. If we assume that r.' -10 pm (Batra and Dullien, 1973), that p@)* -1 mPas, and that (K* + t*) = 0.01 m Ns/m (a conservative estimate), we conclude that N,+, -lo3.…”

Section: Discussionmentioning

confidence: 88%

“…To demonstrate the relative effects of the interfacial tension and the interfacial viscosities, consider a system for which r: = 10 pm (Batra and Dullien, 1973) as oil, and N, = 0.1. We will conservatively estimate K * / c * -1, although the data of Stoodt and Slattery (1984) suggest that the surface dilatational viscosity may be two orders of magnitude larger than the surface shear viscosity.…”

Section: Discussionmentioning

confidence: 99%

Effect of interfacial viscosities upon displacement in sinusoidal capillaries

Giordano

1987

This quantitative analysis shows the relative effects of interfacial tension, interfacial viscosities, and wetting during displacement in a capillary whose radius is a sinusoidal function of axial position. The effect of the interfacial viscosities is to increase the resistance to displacement regardless of the wetting condition. The results are consistent with a previous qualitative analysis and with a previous quantitative analysis for displacement in capillaries whose radii are independent of axial position.In screening surfactant systems for potential use in tertiary oil recovery, it is recommended that the interfacial tension be minimized first, since it determines whether oil displacement will occur, and that the interfacial viscosities be minimized second, since they influence the rate of oil displacement. R. M. Ciordano, J. C. Slattery Department of Chemical EngineeringNorthwestern University Evanston. IL 60201 IntroductionConventional production of light crudes usually concludes with a partial displacement of the oil remaining in the reservoir by either water or brine. For carefully selected, well-designed, good-performing operations, a t the end of conventional petroleum production there remains trapped 50-70% of the oil originally in place (Geffen, 1973).Residual oil is trapped in the form of blobs, each of which occupies possibly a large set of neighboring pores. Once such a blob has been isolated, it may or may not continue to be driven forward by the existing pressure gradient (Slattery, 1974;Oh and Slattery, 1979). If one of its many phase interfaces does advance, it will do so in an episodic fashion: it will slowly creep forward until an instability develops somewhere in the system, it will jump ahead a short distance, and it will begin another period of creeping motion. Since these Haines (1930) jumps take place very rapidly (Heller, 1968), the displacement of residual oil appears to be controlled by the period of slow advancement between jumps.Slattery (1974, 1979) developed a qualitative analysis for these periods of creeping motion. He was able to draw a number of conclusions, one of which is that, when the interfacial tension is less than the critical value required for displacement and the interfacial viscosities are large, equal percentage reductions of the interfacial tension and the interfacial viscosities are equallyThe current address of R. M. Giordano is ARC0 Oil and Gas Co.. Plano, TX 75075.important (Giordano and Slattery, 1983a). (When the interfacial viscosities are small, it is more important to reduce the interfacial tension.) This conclusion has been fully supported both by a quantitative analysis (Giordano and Slattery, 1983a) and by an experimental study (Stoodt and Slattery, 1984) of displacement in capillaries whose radii are independent of axial position.The pores in an oil-bearing rock are not that simple, and an exact solution to the equations of motion for such a porous medium is impractical. In order to simulate displacements under these conditions, we recommend speakin...