The article considers the technology of formation of the converse oil cone below the level of water-oil contact (WOC). The use of this technology makes it possible to reduce the water cut in the production of covert oil on waterfowl. It is important to choose the optimal technological parameters. For the effective application of the technology, a complete cone formation is necessary. This task can be solved by the methods of hydrodynamic modeling, but for the processing of a large array of wells and initial selection of candidates, the development of an analytical technique is advisable.
In this paper, we propose an analytical technique for estimating the formation time of the inverse cone of oil, depending on the properties of the formation and fluids. The basis was the formula for calculating the time of raising the water cone above the WOC level in the case of immiscible liquids in the reservoir with an isotropic absolute permeability. Based on the hydrodynamic modeling a method for taking into account relative phase permeability is proposed. To account for the anisotropy coefficient with the help of hydrodynamic modeling the time dependence of the formation of the oil cone on the anisotropy coefficient for different viscosity ratios of water and oil was constructed. These results are described with sufficient accuracy by a power law. Thus, the formula for calculating water cone parameters is adapted to calculate the oil cone data below the WOC level.
An algorithm for the analytical calculation of the formation time of the oil cone is developed on the basis of well sampling parameters, which makes it possible to quickly estimate the formation time of the oil cone for the given conditions. The proposed algorithm is verified on hydrodynamic models and has a good predictive ability. The practical value of the developed algorithm is the ability to quickly calculate the time of formation of an oil cone for a large number of wells.
1. Kazakov A.A., Solov'ev I.G., Model of dynamics regarding coning of bottom water in oil well (In Russ.), Vestnik kibernetiki, 2009, no. 8, pp. 4–11.
2. Karpychev V.A., To the problem of the cone of bottom water in an inhomogeneous formation (In Russ.), PMTF AN SSSR, 1960, no. 3, pp. 88–113.
3. Kuvanyshev U.P., Nekotorye zadachi prostranstvennoy fil'tratsii v anizotropnykh plastakh (Some problems of spatial filtration in anisotropic formations), Proceedings of TatNIPIneft', 1965, no. 8, pp. 205–214.
4. Skvortsov V.V., Determination of the time of water breakthrough taking into account the difference in viscosities of oil and water (In Russ.), Tatarskaya neft', 1961, no. 4, pp. 21–28.
5. Telkov A.P., Yagafarov A.K., Sharipov A.U., Kleshchenko I.I., Interpretatsionnye modeli neftyanoy zalezhi na stadii razrabotki (Interpretational models of oil deposit under development), Moscow: Publ. of VNIIOENG, 1993, 72 p.
6. Yakupov R.F., Mukhametshin V.Sh., Zeygman Yu.V. et al., Metamorphic aureole development technique in terms of Tuymazinskoye oil field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 10, pp. 36–40.
7. Khisamov R.S., Abdrakhmanov G.S., Kadyrov R.R., Mukhametshin V.V., New technology of bottom water shut-off (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 11, pp. 126–128.
8. Kadyrov R.R., Nizaev R.Kh., Yartiev A.F., Mukhametshin V.V., A novel water shut-off technique for horizontal wells at fields with hard-to-recover oil reserves (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 5, pp.44–47.
9. Kurbanov A.K., Sadchikov P.B., O sovmestnoy dobyche nefti i vody iz zalezhey nefti s podoshvennoy vodoy i gazovoy shapkoy (About joint extraction of oil and water from oil deposits with bottom water and a gas cap), Collected papers “Dobycha nefti” (Oil production), Moscow: Nedra Publ., 1964, pp. 57–62.
10. Danilov V.L., Kats R.M., Gidrodinamicheskie raschety vzaimnogo vytesneniya zhidkostey v poristoy srede (Hydrodynamic calculations of mutual displacement of liquids in a porous medium), Moscow: Nedra Publ., 1980, 347 p.