The results of pilot testing of wet in-situ combustion at Arlanskoye and thermal flooding at the Voyadinsky oil fields of Bashkortostan are considered in the article. These tests were carried out at the end of the last century and were accompanied by a complex of geological, field, hydrodynamic and special borehole studies and analysis of the data obtained. For deep-lying (below 1500 m) productive terrigenous layers of these oil fields, the unsuitability of the wet in-situ combustion process has been established due to a number of serious complications. The effect of advancing the combustion front along the most permeable layers in a geologically heterogeneous porous permeable medium is aggravated. The resulting sulfuric acid gases cause rapid corrosion of tubing, casing pipes, pipelines and field equipment which are technologically and economically unprofitable. The technology of introducing a heating agent into the reservoir (thermal flooding) demonstrates noticeable potential, but its application is limited by the limits of profitability of the process of creating a reservoir heat source. The process is accompanied by heat loss, despite the special lining of tubing through which the heating agent was fed into the formation. The effect of rising columns at the wellhead from thermal expansion is revealed, a continuous thermal fringe in the reservoir system has not been obtained. Based on the geoisotherm map, local fringes of heated water formed around the formed foci of heating agent, but the process remained unexplored. The main problem with thermal enhanced oil recovery methods is the creation of a reservoir source of thermal energy, for which it is necessary to burn part of the oil contained in the reservoir. This problem has found a rational solution in the domestic technology of in-situ combustion, but it turned out to be untenable for sulfurous oil deposits. For the technology of introducing a heating agent into the reservoir, the economic limit is the permissible volume of oil (gas) burned on the surface.
References
1. Babalyan G.A., Voprosy mekhanizma nefteotdachi (Oil recovery mechanism issues), Baku: Aznefteizdat Publ., 1956, 254 p.
2. Markhasin I.L., Fiziko-khimicheskaya mekhanika neftyanogo plasta (Physico-chemical mechanics of oil reservoir), Moscow: Nedra Publ., 1977, 214 p.
3. Surguchev M.L., Vtorichnye i tretichnye metody uvelicheniya nefteotdachi plastov (Secondary and tertiary methods of enhanced oil recovery), Moscow: Nedra Publ., 1985, 308 p.
4. Shakhparonov M.I., Devlikamov V.V., Usacheva T.M. et al., Possibilities for increasing oil recovery using aqueous solutions of micelles-forming surfactants (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1981, no. 11, pp. 35–40.
5. Lozin E.V., On conclusions obtained during field testing of physical and chemical enhanced oil recovery methods on oil fields of the Republic of Bashkortostan
(In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 2, pp. 48–51, DOI: https://doi.org/10.24887/0028-2448-2024-2-48-51
6. Lozin E.V., Razrabotka unikal’nogo Arlanskogo neftyanogo mestorozhdeniya vostoka Russkoy plity (Developing a unique Arlan oil field of the East of the Russian Plate), Ufa: Skif Publ., 2012, 704 p.
7. Mustaev Ya.A., Gabbasov G.Kh., Mavlyutova I.I., Analysis of the development of the Ashitsky experimental site using in situ combustion method (In Russ.), Neftepromyslovoe delo, 1981, no. 10, pp. 6–9.
8. Dzyuba V.I., Rubin E.I., Nikitin V.T., Baymukhametov T.K., Otsenka tekhnologicheskoy effektivnosti zakachki goryachey vody na Voyadinskom mestorozhdenii s pomoshch'yu matematicheskogo modelirovaniya (Assessment of the technological efficiency of hot water injection at the Voyadinskoye field using mathematical modeling), In: Problemy geologii i razrabotki neftyanykh mestorozhdeniy Bashkortostana (Problems of geology and development of oil fields in Bashkortostan), Proceedings of BashNIPIneft, 1993, V. 87, pp. 71–74.
