Assessment of hydrate formation depth in the oil wells, located in a zone of permafrost

About the authors:

Konstantin M. Fedorov, Dr. Sci. (Phys.-Math.), Professor, Professor of the Department of Modeling of Physical Processes and Systems, School of Natural Sciences, University of Tyumen, Tyumen, Russia; k.m.fedorov@utmn.ru, https://orcid.org/0000-0003-0347-3930

Vladimir E. Vershinin, Chief Specialist, Tyumen Petroleum Research Center, Tyumen, Russia; Associate Professor, Department of Physical Processes and Systems Modeling, School of Natural Sciences, University of Tyumen, Tyumen, Russia; ve_vershinin2@tnnc.rosneft.ru

Radik A. Habibullin , Chief geologist of JSC “Payakha”
Artem I. Varavva, Chief Specialist, Gazprom Neft (Tyumen); artevar@yandex.ru

Abstract:

The influence of oil speed on the process of gas hydrates formation in a trunk of an oil well under intensive cooling of products due to the heat exchange with permafrost rock on the example of the Payyhskoe field has been studied. The mathematical model of oil non-isothermal transmission with dissolved gas in a vertical well has been considered. The stationary of rock temperature surrounding the well was a simplifying assumption. Analytical dependence of oil physical properties from the pressure and temperature were applied to the implementation of numerical calculation of a stream parameters. The assessment of conditions of the hydrate formation start was carried out by VNIIGAZ technique. The offered calculation procedure of thermobaric conditions in the wellbore is realized in the form of numerical algorithm. The results of numerical calculations of pressure, temperature, hydrate formation depths are given in a form of graphs. Based on the analysis of thermo-hydraulic calculations of oil flow in the wellbore the border regimes of non-hydrated oil production and the possible depths of the beginning of hydrate formation process were defined. It is shown that in a zone of wellbore passage through permafrost layers at low flow speeds there are favorable conditions for the formation of gas hydrates.

References:

1. Kjerroll, Dzh. Gidraty prirodnogo gaza [Natural gas hydrates]. Translated from English. M.: Premium Inzhiniring, 2007. 316 p. (in Russian).

2. Boxall, J. Gas hydrate formation and dissociation from water-in oil emulsions / J. Boxall, D. Greaves, J. Mulligan. Proceedings of the 6th Int. Conf. on Gas Hydrates (ICGH 2008). Vancouver, British Columbia, July, 2008. Рp. 215‑234.

3. Sloan, E.D. Clathrate Hydrates of Natural Gases / E.D. Sloan, J.E. Dend, C. Koh/3d. Taylor & Francis, CRC Press. 2008. Р. 720.

4. Istomin V.A. Preduprezhdenie i likvidacija gazovyh gidratov v sistemah dobychi gaza [Prevention and elimination of gas hydrates in the systems of gas production] / V.A. Istomin, V.G. Kvon. M.: Gazprom RPI, 2004. 160 p. (in Russian).

5. Instrukcija po kompleksnym issledovanijam gazovyh i gazokondensatnyh skvazhin

«R Gazprom 086-2010» [Instructions for Integrated Research on gas and gas condensate wells «Gazprom 086-2010»]. Part 2. M.: Gazprom expo, 2011. 319 p. (in Russian).

6. Brot, R.A. Defining the reofizicheskih parameters of of gas-saturated oils / R.A. Brot, S.E. Kurtukov. Neftegazovoe delo — Oil and gas business. 2005. Issue 2. Pp. 25-36. (in Russian).

7. Reed, R. Svojstva gazov i zhidkostej [The Properties of Gases and Liquids] / tr. from English. 3d edition / R. Rid, J. Prausnits, T. Sherwood. L.: Himija, 1982. 592 p. (in Russian).

8. Gricenko, A.I. Gidrodinamika gazozhidkostnyh smesej v skvazhinah i truboprovodah [Hydrodynamics of gas-liquid mixtures in wells and pipelines] / A.I. Gricenko, O.V. Klapchuk, Ju.A. Harchenko. M.: Nedra, 1994. 240 p. (in Russian).

9. Brill, J.P. Mnogofaznyj potok v skvazhinah [Multiphase flow in the wells] / Transl. from English. Ju.V. Russkih, ed. M.N. Kravchenko / J.P. Brill, H. Mukherjee. M; Izhevsk: IKI 2006. 384 p. (in Russian).

10. Gubajdullin, A.A., Musakaev, N.G., Borodin, S.L. Mathematical model of the rising gas-liquid flow in a vertical well. Vestnik Tjumenskogo gosudarstvennogo universiteta — Tyumen State University Herald. 2010. № 6. Pp. 68-75. (in Russian).