Viscoelastic and thermodynamic properties of highviscosity oil with different water cut

Dependencies of the viscoelastic and thermodynamic properties of high-viscosity oil from the oil-gathering reservoir of the N-Korenevskoye and Denisovskoye fields on the degree of water cut and temperature have been established. Under the conditions of shear deformations and at comparable temperatures, the nature of the processes of structure formation of oil at a low degree of water cut is due to phase transitions of paraffins, which is consistent with the experimental data described in the literature for non-watered oils, indicating the identity of the nature of intermolecular interactions between non-watered oil and oil with a low degree of water cut. The maximum effect of the thermal method for reducing the viscosity of oil with a low degree of water cut can be achieved when it is heated to the paraffin melting point T_m*, determined using the ln(η) = f (1/T) dependence. The peculiarity of the rheological behavior of high-water-cut oil is due to an increase in the energy of intermolecular interaction, which in the entire temperature range is practically comparable to E_act1 of low-water cut oil at T <T_m*, which is associated with the formationn of invert emulsions stabilized by interphase layers of asphaltene molecules. It is shown that an increase in temperature and shear deformations contribute to a decrease in the values of the effective viscosity of low and high water cut oil; however, the destruction of their colloidal structure does not occur in the entire range investigated. The loss of aggregate and kinetic stability of high-viscosity watered oil is achieved in the presence of a surfactant composition based on Sorbital C-20 and a sodium salt of alkylbenzenesulfonic acid, which causes the desorption of “natural stabilizers” from the oil-water interface and, as a consequence, the coalescence of water droplets.

1. Musina D. N., Vagapov B. R., Sladovskaya O. Yu., Ibragimova D. A., Ivanova I. A. Modern technologies for increasing oil recovery of reservoirs based on surfactants. Vestnik tekhnicheskogo universiteta = Вulletin of the technical university, 2016, vol. 19, no 12, pp. 63–67 (in Russian).

2. Ibragimov N. G., Hafizov A. R., Shaidakov V. V. [et al.]. Complications in oil production. Ufa, Monografiya Publ., 2003. 302 р. (in Russian).

3. Grechukhina A. A., Kabirova L. R., Elpidinsky A. A. Destruction of oil-water emulsions using demulsifying reagents. Kazan, КGТU Рubl., 2004. 36 p. (in Russian).

4. Khutoryansky F. M. Development and implementation of highly efficient oil treatment technologies at electric desalting plants of refineries. Moscow, 2008. 362 p. (in Russian).

5. Formation of emulsions and their classification. Oil and gas production. Available at:http://oilloot.ru/80-dobycha-ipromyslovaya-podgotovka-nefti/504-obrazovanie-emulsij-i-ikh-klassifikatsiya. (accessed 09.04.2021) (in Russian).

6. Pozdnyshev G. N. Stabilization and destruction of oil emulsions. Moscow, Nedra Publ., 1982. 221 p. (in Russian).

7. Levchenko D. N., Bergstein N. V., Khudyakova A. D., Nikolaeva N. M. Emulsions of oil with water and methods of their destruction. Moscow, Khimiya Publ., 1967. 200 p. (in Russian).

8. Schramm L. Emulsions: Fundamentals and Applications in the Petroleum Industry. Washington DC: American Chemistry Society, 1992. 231 p.https://doi.org/10.1021/ba-1992-0231

9. Schubert H., Armbruster H. Principles of Formation and Stability of Emulsions. International chemical engineering, 1992, vol.32, no. 1, pp. 14–28.

10. Pelevin L. A., Pozdnyshev G. N., Mansurov R. I. On the classification and assessment of the effectiveness of oil preparation methods. Neftyanoe khozyaistvo = Oil industry, 1975, no 3, pp. 40–42(in Russian).

11. Vinogradov V. M., Vinokurov V. A. Formation, properties and methods of destruction of oil emulsions: a guideline. Moscow, Gubkin University, 2007. 31 p. (in Russian).

12. State Standard P 51858-2002 Oil. General technical conditions. Moscow, Standartinform Publ., 2006. 15 p. (in Russian).

13. Kondrasheva N. K., Boytsova A. A. Research of quasi-thermodynamic parameters of viscous flow activation of multicomponent hydrocarbon systems. Uspekhi v khimii I khimicheskoi tekhnologii = Advances in chemistry and chemical technology, 2017, vol. XXXI, no 4, pp. 16–18 (in Russian).

14. Ermakov A. A., Mordvinov S. A. On the influence of asphaltenes on the stability of water-oil emulsions. Neftegazovoe delo = Oil and gas business, 2007, no. 1, pp. 1–9 (in Russian).

15. Dobroskok I. B., Lapiga L. A, Klimova L. Z. Analysis of natural stabilizers undestroyed part of oil emulsion process of oil treatment. Neftepromyslovoe delo = Oil field engineering, 1994, no. 7, pp. 17–18 (in Russian).

16. Opanasenko O. N., Krutko N. P., Zhigalova O. L., Luksha O. V., Kozinets T. A. Interphase interactions at the oil-water interface in the presence of surfactants. Vestsi Natsiyanal’nai akademii navuk Belarusi. Seryya khimichnykh navuk = Proceedings of the National Academy of Sciences of Belarus. Chemiсаl series, 2017, no. 2, pp. 34–38 (in Russian).

17. Opanasenko O. N., Krutko N. P., Luksha O. V., Zhigalova O. L., Kozinets T. A. Adsorption of binary mixtures of surfactants at the interface with mineral materials of various nature. Vestsi Natsiyanal’nai akademii navuk Belarusi. Seryya khimichnykh navuk = Proceedings of the National Academy of Sciences of Belarus. Chemiсаl series, 2018, vol. 54, no. 4, pp. 399–405 (in Russian). https://doi.org/10.29235/1561-8331-2018-54-4-399-405