The article presents a geometric method for comparative assessment of formation coverage in steady-state and cyclic waterflooding and an analytical algorithm to divide into groups the injection wells for cyclic waterflooding, taking into account the method of filtration flow redirection. The amount of injection well grouping options for cyclic waterflooding is large enough to calculate each at simulation model. An analytical algorithm has been developed to find the best option for grouping injection wells for cyclic waterflooding, taking into account the method of filtration flow redirection. The area of oil-saturated reservoir zones, additionally involved in production, and their corresponding mobile oil in place are used as the optimization criterion. The main directions of filtration flows are formed in a steady waterflooding and areas of the reservoir that are poorly covered by waterflooding appear. In the first half-cycle of the waterflooding, new directions of filtration flows are formed when some of the injection wells are shut down. Similarly, in the second half-cycle of waterflooding. By obtaining the resulting area of coverage of the oil in place by active production zones after two half-cycles and using the map of current mobile oil in place, we can determine the reserves involved in active production for this grouping of injection wells. The analysis showed that there is a sufficient correlation between the value of additionally covered current mobile oil in place as a result of filtration flow redirection, obtained by analytical evaluation, and technological efficiency, obtained by the results of calculations at simulation model. The results of the analytical evaluation significantly reduce the total time of calculations at simulation model, which allows in a short time to make a decision on the choice of the optimal case of cyclic waterflooding for implementation in the oilfield.

References

1. Kulushev M.M., Gil'miyanova A.A., Petukhov N.Yu. et al., Experience of implementing wellworks to change the direction of fluid filtration in the monolith block of the field of Western Siberia (In Russ.), Territoriya Neftegaz, 2020, no. 11–12, pp. 66–70.

2. Ovchinnikov K.A., Kovaleva G.A., Lebedeva A.V., The experience of oil recovery enhancement of carbonate reservoirs by the method of filtration flows direction change (In Russ.), Neftepromyslovoe delo, 2020, no. 6, pp. 12–16, DOI: 10.30713/0207-2351-2020-6(618)-12-16

3. Fomkin A.V., Petrakov A.M., Bench A.R. et al., Effect for method of changing fluid flow direction on the field with carbonate reservoir (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 10, pp. 96–99.

4. Aubakirov A.R., Designing optimal technology cyclic waterflooding using hydrodynamic modeling (In Russ.), Ekspozitsiya Neft' Gaz, 2015, no. 7, pp. 40–44.

5. Ivanov A.N., Pyatibratov P.V., Aubakirov A.R., Dzyublo A.D., Justification of injection wells operating modes for cyclic waterflooding application (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 2, pp. 28–31, DOI: 10.24887/0028-2448-2020-2-28-31

6. Pyatibratov P.V., Aubakirov A.R., Assessing the impact of reservoir permeability anisotropy on the cyclic waterflooding effectiveness (In Russ.), Ekspozitsiya Neft' Gaz, 2016, no. 5, pp. 60–62.

7. Chertenkov M.V., Chuyko A.I., Aubakirov A.R., Pyatibratov P.V., Zones and regions selecting for cyclic waterflooding (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 8, pp. 60–64.

8. Surguchev M.L., Tsynkova O.E., Sharbatova I.N. et al., Tsiklicheskoe zavodnenie neftyanykh plastov (Cyclical flooding of oil reservoirs), Moscow: Publ. of VNIIOENG, 1977.

9. Sharbatova I.N., Surguchev M.L., Tsiklicheskoye vozdeystviye na neodnorodnyye neftyanyye plasty (Cyclical effects on heterogeneous oil layers), Moscow: Nedra Publ., 1988, 121 p.

10. Kostyuchenko S.V., Direct calculation of the current sweep efficiency at geologic-hydrodynamic modeling (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2006, no. 10, pp. 58-61.

11. Kostyuchenko S.V., Cheremisin N.A., Direct calculation of sweep efficiency and localization of current recoverable oil reserves in digital models (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 7, pp. 94–98, DOI: 10.24887/0028-2448-2019-7-94-98

12. Mett D.A., Aubakirov A.R., The study of signal changes dynamics from disturbing well to observation well (In Russ.), Ekspozitsiya Neft' Gaz, 2017, no. 1, pp. 40–43.

The article presents a geometric method for comparative assessment of formation coverage in steady-state and cyclic waterflooding and an analytical algorithm to divide into groups the injection wells for cyclic waterflooding, taking into account the method of filtration flow redirection. The amount of injection well grouping options for cyclic waterflooding is large enough to calculate each at simulation model. An analytical algorithm has been developed to find the best option for grouping injection wells for cyclic waterflooding, taking into account the method of filtration flow redirection. The area of oil-saturated reservoir zones, additionally involved in production, and their corresponding mobile oil in place are used as the optimization criterion. The main directions of filtration flows are formed in a steady waterflooding and areas of the reservoir that are poorly covered by waterflooding appear. In the first half-cycle of the waterflooding, new directions of filtration flows are formed when some of the injection wells are shut down. Similarly, in the second half-cycle of waterflooding. By obtaining the resulting area of coverage of the oil in place by active production zones after two half-cycles and using the map of current mobile oil in place, we can determine the reserves involved in active production for this grouping of injection wells. The analysis showed that there is a sufficient correlation between the value of additionally covered current mobile oil in place as a result of filtration flow redirection, obtained by analytical evaluation, and technological efficiency, obtained by the results of calculations at simulation model. The results of the analytical evaluation significantly reduce the total time of calculations at simulation model, which allows in a short time to make a decision on the choice of the optimal case of cyclic waterflooding for implementation in the oilfield.

References

1. Kulushev M.M., Gil'miyanova A.A., Petukhov N.Yu. et al., Experience of implementing wellworks to change the direction of fluid filtration in the monolith block of the field of Western Siberia (In Russ.), Territoriya Neftegaz, 2020, no. 11–12, pp. 66–70.

2. Ovchinnikov K.A., Kovaleva G.A., Lebedeva A.V., The experience of oil recovery enhancement of carbonate reservoirs by the method of filtration flows direction change (In Russ.), Neftepromyslovoe delo, 2020, no. 6, pp. 12–16, DOI: 10.30713/0207-2351-2020-6(618)-12-16

3. Fomkin A.V., Petrakov A.M., Bench A.R. et al., Effect for method of changing fluid flow direction on the field with carbonate reservoir (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 10, pp. 96–99.

4. Aubakirov A.R., Designing optimal technology cyclic waterflooding using hydrodynamic modeling (In Russ.), Ekspozitsiya Neft' Gaz, 2015, no. 7, pp. 40–44.

5. Ivanov A.N., Pyatibratov P.V., Aubakirov A.R., Dzyublo A.D., Justification of injection wells operating modes for cyclic waterflooding application (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 2, pp. 28–31, DOI: 10.24887/0028-2448-2020-2-28-31

6. Pyatibratov P.V., Aubakirov A.R., Assessing the impact of reservoir permeability anisotropy on the cyclic waterflooding effectiveness (In Russ.), Ekspozitsiya Neft' Gaz, 2016, no. 5, pp. 60–62.

7. Chertenkov M.V., Chuyko A.I., Aubakirov A.R., Pyatibratov P.V., Zones and regions selecting for cyclic waterflooding (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 8, pp. 60–64.

8. Surguchev M.L., Tsynkova O.E., Sharbatova I.N. et al., Tsiklicheskoe zavodnenie neftyanykh plastov (Cyclical flooding of oil reservoirs), Moscow: Publ. of VNIIOENG, 1977.

9. Sharbatova I.N., Surguchev M.L., Tsiklicheskoye vozdeystviye na neodnorodnyye neftyanyye plasty (Cyclical effects on heterogeneous oil layers), Moscow: Nedra Publ., 1988, 121 p.

10. Kostyuchenko S.V., Direct calculation of the current sweep efficiency at geologic-hydrodynamic modeling (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2006, no. 10, pp. 58-61.

11. Kostyuchenko S.V., Cheremisin N.A., Direct calculation of sweep efficiency and localization of current recoverable oil reserves in digital models (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 7, pp. 94–98, DOI: 10.24887/0028-2448-2019-7-94-98

12. Mett D.A., Aubakirov A.R., The study of signal changes dynamics from disturbing well to observation well (In Russ.), Ekspozitsiya Neft' Gaz, 2017, no. 1, pp. 40–43.