An improved methodology for estimation of two-phase relative permeability functions for heavy oil displacement involving compositional effects and instability
- 36 Downloads
In heavy oil recovery by immiscible gas injection, adverse mobility ratio and gravity segregation along with influential mass transfer are the most crucial factors controlling displacement efficiencies. Obtaining relative permeability functions using conventional techniques that are based on a stable displacement front could be highly misleading. In this work, an improved methodology was proposed for estimating relative permeability curves under simultaneous effects of frontal instability and mass transfer using history-matching techniques. The compositional analysis of produced oil from a coreflood experiment was employed, which represents dynamic interactions more realistically. For the history matching, an optimum, high-resolution, two-dimensional core model was used, as opposed to the industry standard use of a one-dimensional model. The results of the simulation were then verified by a semi-empirical approach using the Koval model, which was then used to predict a similar experiment but in a vertical orientation. A good match was obtained between the forward simulation and the experiment. To highlight the effect of mass transfer on the shape of relative permeabilities, the simulation results from two immiscible gas injection corefloods were compared: CO2 injection with mass transfer and N2 injection without mass transfer. The results showed that the two estimated functions were quite similar, indicating that instability levels would determine the displacement pattern rather than local mass transfer. This integrated approach, therefore, highlights the importance of employing the right fluid model and an appropriate 2D-grid model in estimating relative permeabilities in displacement with instability and mass transfer against the current industry practice.
KeywordsHistory matching Relative permeability Heavy oil CO2 injection Unstable displacement Compositional simulation
Unable to display preview. Download preview PDF.
This work was carried out as a part of the Non-thermal Enhanced Heavy Oil Recovery joint industry project (JIP) in the Centre for Enhanced Oil Recovery and CO2 Solutions of the Institute of Petroleum Engineering at Heriot-Watt University.
The project was equally funded by Total E&P, ConocoPhillips, CONACyT-SENERHidrocarburos - Mexico, Pemex, Wintershall, and Eni, which is gratefully acknowledged. Usman Taura thanks the Petroleum Technology Development fund, Nigeria, for the financial assistance for this work.
- 2.Johnson, E.F., Bossler, D.P., Naumann, V.O.: Calculation of relative permeability from displacement experiments. Pet. Trans. AIME 216(1), 370–372 (1959)Google Scholar
- 8.Cuthiel, D., Kissel, G., Jackson, C., et al.: Viscous fingering effects in solvent displacement of heavy oil. J. Can. Pet. Technol. 45(7), 29–39 (2006)Google Scholar
- 12.Emadi, A.: Enhanced heavy oil recovery by water and carbon dioxide flood. PhD, Heriot-Watt University, Edinburgh (2012)Google Scholar
- 18.Nasrabadi, H., Firoozabadi, A., Ahmed, T.K.: Complex flow and composition path in CO2 injection schemes from density effects in 2 and 3D. In: Proceedingss, 2009 SPE Annual Technical Conference and Exhibition, New Orleans (2009)Google Scholar
- 23.Chuoke, R.L., van Meurs, P., van der Poel, C.: The Instability of Slow, Immiscible, Viscous Liquid-Liquid Displacements in Permeable Media.Society of Petroleum Engineers, General document, SPE-1141-G (1959)Google Scholar
- 26.Christie, M.A., Jones, A.D.W., Muggeridge, A.H.: Comparison between laboratory experiments and detailed simulations of unstable miscible displacement influenced by gravity. In: North Sea oil and gas reservoirs—II: Proceedings of the 2nd North Sea Oil and Gas Reservoirs Conference organised and hosted by the Norwegian Institute of Technology (NTH), Trondheim, Norway, May 8–11, 1989 (1990)Google Scholar
- 29.Farzaneh, S.A., Seyyedsar, S.M., Sohrabi, M.: Enhanced heavy oil recovery by liquid CO2 injection under different injection strategies. In: Proceedings, SPE Annual Technical Conference and Exhibition, p. 21. Dubai (2016)Google Scholar
- 33.Lomeland, F., Ebeltoft, E, Thomas, W.K.: A new versatile relative permeability correlation. In: Proceedings of the International Symposium of the Society of Core Analysts, Toronto (2005)Google Scholar
- 39.Alkindi, A., Muggeridge, A.H., Al-Wahaibi, Y.: The influence of dispersion and diffusion on heavy oil recovery by VAPEX. In: Proceedings, SPE International Thermal Operations and Heavy Oil Symposium, Calgary (2008)Google Scholar
- 40.James, L.A., Rezaei, N., Chatzis, I.: VAPEX, Warm VAPEX and Hybrid VAPEX—the state of enhanced oil recovery for in-situ heavy oils in Canada. J. Can. Pet. Technol. 47, 1–7 (2008)Google Scholar