When ranking the attractiveness of projects for the development of high-viscosity oil fields, a need has been identified for creating a single approach to the selection and rapid assessment of the efficiency of the technology of thermal methods for enhancing oil recovery (EOR). The purpose of this work is to create a convenient and fast tool for solving this problem.
In this paper, a comparative analysis of existing analytical methods for planning thermal EOR is carried out: steam assisted gravity drainage (SAGD), constant or cyclic steam injection, heating of the formation by borehole heaters. The limits of applicability of the models most often used in the literature are determined. For cases where formation parameters do not allow the use of analytical approaches to account for the entire range of physical parameters occurring in the formation under the influence of the thermal fluid, a new engineering tool is proposed. Its implementation is based on solving the equations of two-dimensional multicomponent multiphase non-isothermal filtration in an anisotropic formation. At the same time, the proposed tool allows us to directly use empirical dependencies and correlations obtained from the results of laboratory studies of core and oil or on formation-analogues.
As a result of the work, software was created for performing operational engineering calculations on simplified two-dimensional non-isothermal simulation models, which allows modeling and evaluating the effectiveness of various thermal methods for enhancing oil recovery on the formation. The developed algorithms significantly reduce the calculation time, without losing accuracy, take into account the type of completion of wells and the geometry of the "formation-well" system under various conditions at the reservoir boundaries and at the well. The possibility of cumulative accounting of the effect of physical effects in the process of thermal action is realized: change in wettability and relative permeability (including residual oil saturation), thermal expansion of fluid and rocks, oil distillation, change in the initial shear gradient for oil, and others.
References
1. Yudin E.V., Vorob'ev K.V., Bykov A.A., Stepanenko I.K., Calculation model for estimating the change of hot fluid properties along the wellbore during the steam injection (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 3, pp. 50-53.
2. Yudin E., Lubnin A., Lubnina E. et al., New engineering tools for rapid assessment of the efficiency of thermal methods for enhancing oil recovery (In Russ.), SPE 191608-18RPTC-RU, 2018.
3. Varx J.W., Langenheim R.H., Reservoir heating by hot fluid injection, Trans. Am. Inst. Min., Metall. Pet. Eng., 1959, V. 216, pp. 312–315.
4. Jones J., Steam drive model for hand-held programmable calculators, SPE 8882-PA, 1981.
5. Jones J., Why cyclic steam predictive models get no respect, SPE 20022-PA, 1992.
6. Jones J., Cyclic steam reservoir model for viscous oil, pressure depleted reservoirs, SPE 6544, 1977.
7. Van Lookeren J., Calculation methods for linear and radial steam flow in oil reservoirs, SPE 6788, 1977.
8. Wu Z., Vasantarajan S., Optimal soak time for cyclic steam stimulation of a horizontal well in gravity drainage reservoirs, SPE 146716-MS, 2011.
9. Wu Z., Vasantharajan S., El-Mandouh M., Suryanarayana P.V., Inflow performance of a cyclic-steam-stimulated horizontal well under the influence of gravity drainage, SPE 127518-PA, 2011.
10. Khisamov R.S., Morozov P.E., Khayrullin M.Kh. et al., The analytical model for development of heavy oil deposit by steam-assisted gravity drainage method (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 2, pp. 62–64.
11. Mao Deming, Xie Xueying, Jones M.R., Harvey A., Karanikas J.M., A simple approach for quantifying accelerated production through heating producer wells, SPE 181757-PA, 2017.
