The field experience with application of various methods of prevention and remediation of wax deposition in tubing has shown that none of the methods provides 100 % protection and each need to be duplicated by other methods with the exception of using electrical heating and scrapers. Among the prevention methods of wax deposition, the magnetic treatment of oil using magnetic devices of various designs is quite effective and simple in production and handling. Over the past decades, a great experience on using the magnetic treatment on production fluids has been gained. At the same time, not all observed phenomena and effects have a rigorous explanation. This paper discusses the effect of a magnetic field on the wax deposits; an analytical model has been developed to quantify the wax deposition rate on the tubing surface during magnetic treatment of the upstream. It has been established that the passage of the oil flow through a non-uniform magnetic field causes a high-intensity electric field for a sufficiently long period of time, the effect of which decreases the solubility of wax in oil, increases the intensity of wax crystallization in the volume of oil and reduces the wax deposition on the tubing surface. The model takes into account that the presence of wax deposits on the tubing surface is a highly efficient heat insulator that changes the temperature regime of the flow and the temperature of the tubing wall. A method for calculating the equilibrium concentration of wax and changing in the solubility of wax in oil as a result of the influence of a constant electric field has been developed. It has been shown that the effect of magnetic treatments rises with the increase in the concentration of asphaltenes in oil and water cut.
References
1. Cheremisin N.A., Issledovanie mekhanizma obrazovaniya parafinogidratnykh probok v neftyanykh skvazhinakh s tsel'yu sovershenstvovaniya metodov bor'by s nim (Study of the mechanism of formation of paraffin hydrate plugs in oil wells in order to improve methods of dealing with it): thesis of candidate of technical science, Tyumen, 1992.
2. Pivovarova N.A., Magnitnye tekhnologii dobychi i pererabotki uglevodorodnogo syr'ya. Obzornaya informatsiya (Magnetic technologies for extraction and processing of hydrocarbon raw materials. Overview information), Moscow: Publ. of Gazpromekspo, 2009, 120 p.
3. Shchekhovtseva E.V., Roman'ko V.V., Kim S.L., Relevance of application of magnetic inductors use when operating a complicated fund of wells (In Russ.), Neftepromyslovoe delo, 2020, no. 3, pp. 52–58.
4. Leont'ev A.Yu., Poletaeva O.V. et al., Magnetic field influence on the rheological properties of heavy highly viscous oils (In Russ.), Neftegazokhimiya, 2019, no. 3–4, pp. 18–22.
5. Zlobin A.A., The mechanism of magnetic activation of oil for well protection against asphaltene deposits (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 1, pp. 52–56.
6. Lesin V.I., Eremin N.A., The natural and synthesized nanoscale iron oxides - nanobots in the control processes of the production, the transportation, the preparation and the refining of oil by using the magnetic field (In Russ.), Neft'.Gaz.Novatsii, 2018, no. 1, pp. 18–22.
7. Patent RU 2 623 758 C1, Blast-hole magnetic complex for formation fluid processing in bottom-hole zone, Inventor: Soldatova I.P.
8. Fedorov E.E., Razrabotka metodov ponizheniya vyazkosti nefti i deparafinizatsii promyslovykh truboprovodov s ispol'zovaniem elektricheskogo polya (Development of methods for reducing the viscosity of oil and dewaxing field pipelines using an electric field): thesis of candidate of technical science, Ivano-Frankovsk, 1982.
9. Malyshev A.G., Cheremisin N.A., Shevchenko G.V., Choosing the best ways to control of paraffin-hydrate formations (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1997, no. 9, pp. 62–69.
10. Apasov T.K., Apasov G.T., Sarancha A.V., Fighting with deposits AFS, salts and corrosion by the application of magnetic activators (In Russ.), Sovremennye problemy nauki i obrazovaniya, 2015, no. 2-2, pp. 66–66.
11. Loskutova Yu.V., Yudina N.V., Influence of a magnetic field on the structural-rheological properties of oils (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta, 2006, V. 309, no. 4, pp. 104–109.
12. Patent US5024271A, Permanent-magnet wax-proof device, Inventor: Meihua W.
13. Gupalo Yu.P., Polyanin A.D., Ryazantsev Yu.S., Massoobmen reagiruyushchikh chastits s potokom (Mass transfer of reacting particles with the flow), Mocsow: Nauka Publ., 1985, 336 p.
14. Lifshits E.M., Pitaevskiy L.P., Fizicheskaya kinetika (Physical kinetics), Moscow: Nauka Publ., 1979, 528 p.
15. Reid R.C., Prausnitz J.M., Sherwood T.K., The properties of gases and liquids, New York: McGraw-Hill, 1977.
16. Frolov Yu.G., Kurs kolloidnoy khimii (Colloid chemistry course), M.: Khimiya, 1989. – 464 s.
17. Rumer Yu.B., Ryvkin M.Sh., Termodinamika. Staticheskaya fizika i kinetika (Thermodynamics. Static physics and kinetics), Moscow: Nauka Publ., 1977, 552 p.
18. Tronov V.P., Mekhanizm obrazovaniya smolo-parafinovykh otlozheniy i bor'ba s nimi (Mechanism of formation of resin-paraffin deposits and its control), Moscow: Nedra Publ., 1970, 192 p.
19. Chernov A.A., Trusov L.M., Electrostatic effects during the formation of nuclei on the surface (In Russ.), RNTS VNIIOENG, 1979, no. 5, pp. 3–5.
20. Markhasin I.L., Fiziko-khimicheskaya mekhanika neftyanogo plasta (Physical and chemical mechanics of an oil reservoir), Moscow: Nedra Publ., 1977, 214 p.
21. Vakhitov G.G., Simkin E.M., Ispol'zovanie fizicheskikh poley dlya izvlecheniya nefti iz plastov (Using physical fields to extract oil from reservoirs), Moscow: Nedra Publ., 1985, 230 p.
22. Medvedev V.F., Sbor i podgotovka neustoychivykh emul'siĭ na promyslakh (Gathering and preparation of unstable emulsions in the fields), Moscow: Nedra Publ., 1987, 144 p.