In the course of oil fields development, the well operation conditions get worse: reduction of reservoir pressure, increase of water-in-oil content. This puts an end to the natural flow and initiates the artificial lift period, when it is necessary to apply additional (to reservoir) energy fr om the surface of any type. Gaslift operation method considers application of a pressurized gas. High content of paraffins and resin, high reservoir temperature and pour point, high gas saturation and bubble pressure, low well productivity indexes are those factors, which lim it the application area for any artificial lift operation type.
The principle of gaslift operation is to produce the well products by injecting the necessary amount of pressurized gas-type working substance into the well. The complicated geotechnical conditions of developed areas in Vietsovpetro JV before approving the technical-technological solutions require the following research and engineering works in oil production techniques and technologies: 1) pilot tests of various artificial lift methods to justify the areas for effective implementation; 2) analysis of the downhole equipment operation and selection of the efficient downhole equipment assembly.
Implementation of the straight gaslift system in the pilot area of Vietsovpetro JV proved the possibility of applying the straight gaslift in the field before constructing the compressor station and gaslift cycle facilities by high-pressure gas offtake from oil wells. Based on the analysis of technological parameters of wells performance and Vietsovpetro JV development areas, defined the well categories, which operate by potential methods, require conversion to straight gaslift, as well as the wells with reserves for production enhancement. The tests proved that the straight gaslift operation method possesses significant potential and high technological effectiveness for fluid production improvement.
References
1. Repin N.N., Devlikamov V.V., Yusupov O.M., D'yachuk A.I., Tekhnologiya mekhanizirovannoy dobychi nefti (Technology of mechanized oil production), Moscow: Nedra Publ., 1976, 175 p.
2. Ty Tkhan' Ngia, Veliev M.M., Gazliftnaya ekspluatatsiya skvazhin (Gas-lift operation of wells), St.Petersburg: Nedra Publ., 2016, 384 p.
3. Printsipial'naya tekhnologicheskaya skhema sbora, podgotovki i vneshnego transporta do KPN nefti i gaza severnogo i yuzhnogo svodov mestorozhdeniya “Belyy Tigr” (The basic technological scheme of collection, preparation and external transport to the CIT of oil and gas of the northern and southern arches of the White Tiger field), Moscow: Publ. of VNIPImorneftegaz, 1989, 144 p.
4. RD-SP-31-89, Kompleks vnutriskvazhinnogo oborudovaniya s klapanom-otsekatelem. Osnashchenie i osvoenie fontannykh i gazliftnykh skvazhin (Complex of downhole equipment with shut-off valve. Equipping and development of fountain and gas lift wells),Vung Tau: Publ.of NIPImorneftegaz, 1989, 54 p.
