The article presents the results of experimental study of the influence of operating fluid pressure on the ejector characteristics for subsequent use in perfecting the technique of selecting the most suitable flow part of a jet apparatus during well operation with electrical submersible pump unit (ESP) units and pumping gas from the annulus to the tubing. The characteristics of the jet apparatus were studied on an experimental stand, on the basis of which pressure distribution curves were constructed along the length of the flowing part (mixing chamber and diffuser) of a liquid-gas ejector at various pressures of the working fluid in front of the nozzle. The dependences of the relative dimensionless pressure drop and the efficiency of the ejector on the pressure of the working fluid in front of the nozzle to assess the efficiency of the ejector at various operating pressures were also represented. The dependence of the optimal operating mode of a liquid-gas ejector on the magnitude of the working pressure is revealed. In the experiments, the pressure distribution curves along the length of the ejector were measured and the characteristics of the jet apparatus were obtained when gas was evacuated by a liquid jet with accuracy suitable for practical purposes. It is shown that with a decrease in the working pressure, the character of the pressure distribution along the length of the ejector dramatically changes. The provision is added that the most optimal mode for a liquid-gas ejector is the mode in which the process of mixing flows is completed directly in front of the diffuser - the optimal mode also depends on the magnitude of the working pressure. The results of experimental studies expand the possibilities of optimizing the flow part of ejectors for use in various pump and ejector technologies for SWAG in order to utilize associated petroleum gas and increase oil recovery. Based on the results of experimental studies presented in the article, the most suitable for the characteristics of the flow part of the ejector can be selected, including the length of its mixing chamber during operation with ESP units and pumping gas from the annulus into the tubing.
References
1. Fleshman R., Lekic O.H., Artificial lift for high-volume production, Oilfield Review, 2000, V. 12, no. 1, pp. 49–63.
2. Carvalho P.M., Podio A.L., Sepehrnoori K., An electrical submersible jet pump for gassy oil well, Journal of Petroleum Technology, 1999, V. 51, no. 5, pp. 34–36.
3. Mishchenko I.T., Gumerskiy Kh.Kh., Mar'enko V.P., Struynye nasosy dlya dobychi nefti (Jet pumps for oil production), Moscow: Neft' i gaz Publ., 1996, 150 p.
4. Drozdov A.N., Influence of free gas on submerged pumps characteristics (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2003, no. 1, pp. 68–70.
5. Lyamaev B.F., Gidrostruynye nasosy i ustanovki (Hydrojet pumps and units), Leningrad, Mashinostroenie Publ., 1988, 256 p.
6. Drozdov A.N., Rational using of pump-ejector systems may eliminate many disadvantages adherent to blade and stream pumps (In Russ.), Burenie i neft', 2012, no. 3, pp. 26–28.
7. Drozdov A.N., Wells operation technologies with immersible pumps at low bottom-hole pressures (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2003, no. 6, pp. 86–89.
8. Drozdov A.N., Tekhnologiya i tekhnika dobychi nefti pogruzhnymi nasosami v oslozhnennykh usloviyakh (Technology and engineering of oil production using submersible pumps under complicated conditions), Moscow: MAKS press Publ., 2008, 312 p.
9. Topol'nikov A.S., Urazakov K.R., Vakhitova R.I., Saracheva D.A., The method of calculation of parameters of jet pump attached to joint operation with submersible electric pump (In Russ.), Neftegazovoe delo, 2011, no. 3, pp. 134–146.
10. Saracheva D.A., Sovershenstvovanie elektrotsentrobezhnykh nasosnykh ustanovok dlya skvazhin, oslozhnennykh vysokim gazovym faktorom (Improving electric centrifugal pumping units for wells complicated by high gas factor): thesis of candidate of technical, Ufa, 2016.
11. Urazakov K.R., Mukhin I.A., Vakhitova R.I., Modeling the characteristics of jet pump (In Russ.), Elektrotekhnicheskie i informatsionnye kompleksy i sistemy, 2015, V. 11, no. 4, pp. 41–50.
12. Sokolov E.Ya., Zinger N.M., Struynye apparaty (Jet devices), Moscow: Energoatomizdat Publ., 1989, 352 p.
13. Tsegel'skiy V.G., Dvukhfaznye struynye apparaty (Two-phase jet devices), Moscow: Publ. of Moscow State Technical Bauman University, 2003, 408 p.
14. Spiridonov E.K., Constructions of liquid-gas jet pumps. State and prospects (In Russ.), Vestnik YuUrGU, 2005, no. 1, pp. 94–104.
15. Kuz'michev N.D., Short-term operation of wells and prospects for the development of oil-producing equipment (In Russ.), Territoriya NEFTEGAZ, 2005, no. 6, pp. 22–36.
16. Drozdov A.N., Drozdov N.A., Laboratory researches of the heavy oil displacement from the Russkoye field’s core models at the SWAG injection and development of technological schemes of pump-ejecting systems for the water-gas mixtures delivering, SPE-157819-MS, 2012.
17. Drozdov A.N., Drozdov N.A., Bunkin N.F., Kozlov V.A., Study of suppression of gas bubbles coalescence in the liquid for use in technologies of oil production and associated gas utilization, SPE-187741-MS, 2017.
