Solvent Induced Oil Viscosity Reduction and Its Effect on Waterflood Recovery Efficiency

B. Ghosh, E. W. Al Shalabi

Abstract


WAG process is one of the techniques used for reducing gas consumption, enhancing recovery factor and achieving better profile control of displacing fluids. Recovery efficiency due to reduction of oil viscosity, simulating a WAG process, in a wide range of reservoir permeability and water injection rate was investigated. Gas viscosity reduction by miscible gas or solvent injection is mimicked by progressive dilution of a medium density crude oil with a mixture of hydrocarbon solvent. The porous media used in this study consists of a set of water wet sandstone core plugs of low to medium permeability. The experimental findings  show that reduced oil viscosity has no correlation with recovery efficiency, in the normal flood velocity regime. However, in the higher flood velocity regime, recovery efficiency reduces with increasing oil viscosity, only for higher permeability cores, which is attributed to micro-heterogeneity within pore geometry. The study suggests that the additional oil recovery during miscible gas injection, is mainly contributed by the swelling factor of oil which results in increased oil saturation, higher reservoir pressure and increased relative permeability of oil in addition to the contribution from lower interfacial tension and very little, if any due to oil viscosity reduction.
Key words: WAG process; Recovery efficiency; Oil viscosity

Keywords


WAG process; Recovery efficiency; Oil viscosity

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References


[1] Ahmed, T. (2001). Reservoir Engineering Handbook. Gulf Professional Publishing.

[2] Chuoke, R. L., et al. (1959). The Instability of Slow, Immiscible, Viscous Liquid-Liquid Displacements in Permeable Media. AIME, 216, 188-194.

[3] Peters, E.J., & Flock, D. L. (1981). The Onset of Instability During Two-Phase Immiscible Displacement in Porous Media. Soc. Petrol. Eng. J., 21(2), 249−258.

[4] Pirson, S. J. ed. (1958). Oil Reservvoir Engineering (pp.555-557). New York: McGraw Hill.

[5] Kumar, M., Hoang, V., & Satick, C. (2005). High Mobility Ratio Water Flood Performance Prediction: Challenges and New Insights. SPE Reservoir Evaluation & Engineering, 11(1), 186-196.

[6] Al Jarba, M., & Al Anazi, B.D. (2009). A Comparison Study of the of the CO2-Oil Physical Properties-Literature Correlations Accuracy Using Visual Basic Modeling Technique. Oil and Gas Business.

[7] Schramm, L.L., et al. (2000). Technology Development for Conventional Petroleum Reservoirs. J. of Can. Pet. Technology, 31–46.

[8] Jakupsstovu, S. I., et al. (2001). Proc. of the 6th Nordic Symp: Upscaling of miscible displacement processes. Petrophysics.

[9] Lansangan, R. M. (1993). Viscosity, Density and Composition Measurement of CO2/West Texas Oil Systems. SPE Reservoir Engineering, 175-182.

[10] Bon, J., & Sarma, H. K. (2004). A Technical Evaluation of a CO2 Flood for EOR and Greenhouse Gas Sequestration Benefits. SPE 88451.

[11] Fulop, R., et al. (1997). Enhanced Oil Recovery by CO2 Flooding. Paper presented at 15th World Petroleum Congress.

[12] Hinderaker, L., et al. (1996). RUTH – A Comprehensive Norwegian R&D Program on IOR. SPE 36844. Paper presented at the SPE European Petroleum Conference.

[13] Ataei, A., et al. (2011). Investigation of Different I-WAG Schemes Towards Optimization of Displacement Efficiency. SPE 144891. Paper presented at the SPE Enhanced oil recovery conference, Kuala Lumpur.

[14] Mai, A., & Kantzas, A. (2007). Heavy Oil Waterflooding: Effects of Flow Rate and Oil Viscosity. Canadian International Petroleum Congress, 144.

[15] Abrams, A. (1975). The Influence of Fluid Viscosity, Interfacial Tension and Flow Velocity of Residual Oil Saturation Left by Waterflood. SPE Journal, 15(5), 437-47.

[16] Beliveau, D. (2008). Waterflooding Viscous Oil Recovery. SPE 113132.

[17] Arps, J.J., et al. (1967). Statistical Analysis of Crude Oil Recovery and Recovery Efficiency. Bulletin D14, American Petroleum Institute.

[18] Doscher, T. M., et al. (1984). Statistical Analysis of Crude Oil Recovery and Recovery Efficiency. API Bulletin D14 Second Edition.




DOI: http://dx.doi.org/10.3968/j.aped.1925543820110202.112

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