The article is devoted to the reservoir properties analysis of the OI-II formation at the Srednebotuobinskoye oil-gas-condensate field, which is one of the largest in Eastern Siberia. The field was discovered in 1970. The main target is the ancient Vendian sandstones of the Botuobinsky horizon. The production started in 2013. The second largest reservoir is the OI-II formation, but this object is still at the stage of exploration. Reservoir zones of the Osinsky horizon with improved properties are distinguished according to 3D seismic data and have an annular shape in plan ("ring anomalies"). The ring anomalies are limited not only in area, but also in depth – they occupy only a part of the section of the Osinsky horizon. Since earlier the assessment of the properties of the formation was carried out over the entire section of the formation, the ring anomalies, as an interval in the section, was not distinguished. Due to this, there was no correlation between the zone of improved reservoir properties and ring anomalies. In the present study, it is customary to compare properties in three intervals when analyzing the properties of the Osinsky horizon: only the ring, the zone outside the ring (above and below) and the entire Osinsky horizon. For a more confident identification of the ring anomalies intervals inside the Osinsky horizon according to log data, the subsidiary of Rosneft Oil Company - RN-Exploration LLC applied the approach of constructing probability density maps based on the values of the interval time of the p-wave and neutron porosity. Thanks to a new approach for the allocation of objects and reservoir properties estimation by, the boundaries of the intervals of ring anomalies in wells were clarified, a drilling rating on wells was compiled, a plan for further study of anomalies was made.

References

1. Dolgova E.I., Yukhnevich A.V., Syrchina N.V. et al., Sequential stratigraphie and facies analysis of Vendian terrigenous deposits at Srednebotuobinskoye field (the Mirny arch of the Nepa-Botuoba anteclise) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 8, pp. 12–16, DOI: 10.24887/0028-2448-2021-8-12-16

2. Sharapova E.S., Sultanov R.B., Urenko R.S. et al., Structural features of carbonate horizon OI-II, Srednebotuobinskoe field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 7, pp. 70–73, DOI: 10.24887/0028-2448-2021-7-70-73

Scientists have been interested in studying the lithological composition, geological structure and stratification of sections, reservoir properties, saturation, conditions and history of the development of Upper Cretaceous deposits (K2) of the Eastern Caucasus for more than 70 years. The problem of further study of Upper Cretaceous deposits and associated hydrocarbon deposits is very complex and relevant. In previos work the authors showed the similarities and differences of the geological structure and conditions of the development of Upper Cretaceous deposits within a number of regions of the Eastern Caucasus: Eastern Stavropol, the Republique of Ingushetia, and the Chechen Republic. The deposits are differentiated by the depths of their occurrence, the conditions of formation and maturity, the types of reservoirs, the presence of discontinuous faults, the intensity and composition of fluid inflows. The formed mature high-amplitude (over 250-500 m), complicated by discontinuous disturbances of various order, including intrawater dislocations, Upper Cretaceous traps of the Chechen Republic and the Republique of Ingushetia are characterized by initial fluid flow rates up to 200-3000 t/day and practically anhydrous hydrocarbons tributaries. For low-amplitude (less than 50 m) underformed deposits of Eastern Stavropol and Plain Dagestan, not rich in intra-water faults, less representative fluid flow rates (more often under 100-150 t/day) with a high water content at all stages of development are characteristic. The tendency of the dependence of the intensity and composition of tributaries on the amplitude of Upper Cretaceous deposits and a number of other factors was traced by the authors within the Eastern Stavropol territory. The differentiation of "non-standard" traps of the region according to the features of the lithological and stratigraphic structure, the potential of carbonate reservoirs, taking into account the tectonic, geochemical and geological prerequisites for their formation, is carried out.

In this article specialists of Rosneft Company and its subsidiary Rosneft-NTC have identified and analyzed the signs of the most promising Maastricht zones of the Eastern Stavropol Region that are relevant when searching for missed traps, planning well interventions and contributing to improving the efficiency of the Company's field development. These features can be applied to other oil and gas bearing areas with similar geological conditions. Also, recommendations are given for optimizing the development processes of immature hydrocarbons deposits in carbonate cavern-crack rocks.

References

1. Braylovskiy A.L., Povyshenie effektivnosti geofizicheskikh issledovaniy skvazhin dlya izucheniya slozhnykh karbonatnykh kollektorov (na primere verkhnemelovykh otlozheniy Prikumskoy sistemy podnyatiy) (Improving the efficiency of well logging for the study of complex carbonate reservoirs (by the example of the Upper Cretaceous deposits of Prikumsk the uplifts)): thesis of candidate of geological and mineralogical science, Groznyy, 1985, 219 р.

2. Braylovskaya A.A., Miroshnichenko V.V., Oks L.S., Yatsenko V.M., A comprehensive approach to the re-evaluation of the geological structure of ‘low-pore’ deposits in a limited set and low quality of initial data on the example of deposits in the Republic of Ingushetia (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 10, pp. 30–36, DOI: 10.24887/0028-2448-2020-10-30-36

3. Chepak G.N., Polosin B.A., Plotnikov M.S. et al., Reservoir properties of carbonate rocks of the Triassic and Upper Cretaceous of the Eastern Stavropol region (In Russ.), Neftegazovaya geologiya i geofizika, 1980, no. 12, pp. 6–9.

4. Stulov L.G., Tomashev D.V., Paporotnaya A.A., Features of the geological structure and location of oil deposits in the Cretaceous (Maastrichtian stage) natural reservoir (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 2, pp. 33–35.

5. Nelepov M.V., Tektonicheskie usloviya formirovaniya zalezhey uglevodorodov mezozoyskikh otlozheniy Vostochnogo Predkavkaz'ya (Tectonic conditions for the formation of hydrocarbon deposits in the Mesozoic deposits of the Eastern Ciscaucasia): thesis of candidate of geological and mineralogical science, Stavropol, 2005, 188 р.

6. Neruchev S.G., Nefteproizvodyashchie svity i migratsiya nefti (Oil producing formations and oil migration), Leningrad: Nedra Publ., 1962, 224 р.

7. Panchenko A.S., Voprosy formirovaniya zalezhey uglevodorodov v mezozoyskikh otlozheniyakh Predkavkaz'ya (Issues of the formation of hydrocarbon deposits in the Mesozoic deposits of Ciscaucasia), Collected papers “Geologiya, razvedka i razrabotka gazovykh i gazokondensatnykh mestorozhdeniy Severnogo Kavkaza“ (Geology, exploration and development of gas and gas condensate fields in the North Caucasus), Proceedings of  SKF VNIIgaz, 1971, no. 4, pp. 61–71.

8. Mikhaylov N.N., Motorova K.A., Sechina L.S., Smachivaemost' neftegazovykh plastovykh sistem (Wettability of oil and gas reservoir systems), Moscow: Publ. of Gubkin University, 2019, 360 p.

9. Golf-Racht T., Fundamentals of fractured reservoir engineering, Amsterdam, New York: Elsevier, 1982, 608 р.

This article completes the cycle of scientific publications of Rosneft Oil Company devoted to the comprehensive study of the Bazhenov-Abalak complex (BAC) on the territory of the Krasnoleninsky arch. The authors focused on the results of petrophysical modeling and interpretation of well logging data in the BAC interval, which became the basis for petroelastic and seismogeological modeling. The tectonophysical analysis of the morphostructure on the roof of the Bazhenov formation and the results of a joint analysis of fracturing according to core, well logging and FMI data allowed to substantiate a fundamental tectonic model of the work area and a 3D model of discrete cracks (DFN). The article describes in detail the process of creating a DFN model taking into account the complex forecast trend of crack intensity and individual parameters for fractured zones. The results of the final stage of the work reflect the study and justification of the key criteria for localization of the most productive zones in an unconventional fractured-cavernous oil and gas reservoir. The analysis of a number of criteria for the localization of hydrocarbons in unconventional reservoirs from different regions allowed not only to develop and justify the most significant among them for a particular subsurface area, but also to emphasize the individuality of the choice of significant localization parameters for different types of BAC sections. The final solution for the localization of the potential producing zone was a complex parameter of the quality of reserves, which was calculated individually for each of the YUK0 and YUK1 formations. Based on the quality map, the area was ranked taking into account geological and commercial risks and the most promising areas for pilot work were identified, wells were recommended for confirmation and study of highly productive zones.

References

1. Kuz'mina S.S., Avramenko E.B., Smyshlyaeva M.D., Grishchenko M.A., Produktivnost' treshchinovatykh kollektorov na primere bazheno-abalakskogo kompleksa mestorozhdeniya Krasnoleninskogo svoda (Features of productivity of fractured reservoirs on the example of the Bazheno-Abalak complex of the Krasnoleninsky anticline), EAGE, Proceedings of Geomodel 2019 conference, September 2019, V. 2019, pp. 1 – 5, DOI: https://doi.org/10.3997/2214-4609.201950021

2. Musatov I.V., Novokreshchin A.V., Gayfulina E.F., Grishchenko M.A., Issledovanie bazheno-abalakskogo kompleksa na Krasnoleninskom svode s pomoshch'yu seysmicheskikh metodov (Exploration of Bazhen-Abalak complex at Krasnoleninsky arch by seismic methods), Proceedings  of EAGE/SPE Workshop on Shale Science 2021, 2021, V. 2021, pp. 1–5, DOI: https://doi.org/10.3997/2214-4609.202151009

3. Avramenko E.B., Grishchenko M.A., Akhmadishin A.T. et al., Application of geo-chemical indicators for sedimentology description clarifying of Bazhenov and Abalak formation in Krasnoleninskoe field, SPE-191489-18RPTC-RU, 2018, https://doi.org/10.2118/191489-18RPTC-MS

4. Marinov V.A., Alifirov A.S., Bumagina V.A. et al., Stratigraphy and formation conditions of Callovian and Upper Jurassic deposits of the central part of the Kazym-Konda region (West Siberia) (In Russ.), Geologiya i mineral'no-syr'evye resursy Sibiri, 2021, no. 2 (46), pp. 3–16, DOI: 10.20403/2078-0575-2021-2-3-16

5. Kudamanov A.I., Marinov V.A., Bumagina V.A. et al., Osnovnye zakonomernosti stroeniya i evolyutsiya osadkonakopleniya verkhney yury Krasnoleninskogo svoda Zapadnoy Sibiri (Basic regularities in the structure and evolution of sedimentation of the Upper Jurassic of the Krasnoleninsky arch of Western Siberia), Proceedings of TNNC, 2018, V. 4, pp. 111-129.

6.  Kalmykov G.A., Stroenie bazhenovskogo neftegazonosnogo kompleksa kak osnova prognoza differentsirovannoy nefteproduktivnosti (The structure of the Bazhenov oil and gas bearing complex as the basis for the forecast of differentiated oil production): thesis of doctor of geological and mineralogical science, Moscow, 2016, 391 р.

7. Khabarov A.V., Oshnyakov I.O., Aleksandrova I.O. et al., A multidimensional analysis of logs and core as a tool for the petrophysical typing of the Bazhenov-Abalak association (In Russ.), Karotazhnik, 2019, V. 300, no. 6, pp. 86–102.

8. Khabarov A.V., Volokitin Ya.E., Procedure for combined analysis of core and log data for lithologic classification of Terrigenous reservoirs (In Russ.), Karotazhnik, 2009, no. 12 (189), pp. 83–129.

9. Gayfulina E.F., Novokreshchin A.V., Ispol'zovanie rezul'tatov inversionnykh preobrazovaniy pri prognoze potentsial'no produktivnykh zon v intervale bazheno-abalakskogo kompleksa (Krasnoleninskiy svod) (Using the results of inversion transformations in predicting potentially productive zones in the interval of the Bazheno-Abalaksky complex (Krasnoleninsky arch)), Proceedings of Trofimuk readings Novosibirsk, 2019, http://conf.ict.nsc.ru › conferences › trofimuk2019

10.  Agalakov S.E., Gayfulina E.F., Grishchenko M.A. et al., New directions of prospecting and exploration of hydrocarbon accumulations (In Russ.), Delovoy zhurnal NEFTEGAZ.RU, 2020, no. 7, pp. 58–64.

Kashirskian sequence deposits of the Moscow stage are promising for replenishing the resource base of the Volga-Ural oil and gas province in conditions of depletion of the basic horizons oil reserves. In the Kashirskian sequence, 8 elementary cyclites are distinguished. These cycites have a similar lithological structure and contain signs subaeral erosion at the top. The cyclites are composed of the following lithological types of rocks: clayey mudstones (1), spongolitic siliceous limestones and silicites (2), organic-rich laminated wackestones (3), bioclastic wackestones-packstones (4), bioturbated packstones (5), foraminiferal grainstones (6), polydetritic grainstones (7), laminated bioclastic packstones (8), microcrystalline massive dolomites (9), microcrystalline laminated dolomites (10) and microcrystalline patterned dolomites (11). The main reservoirs are represented by microcrystalline dolomites with high porosity and relatively low permeability and foraminiferal grainstones, similar in properties to terrigenous reservoirs. The C2ks4 reservoir in the lower part of the Kashirskian sequence is composed of foraminiferal grainstones. It is covered by the seal of clayey limestones lithotype (1). The C2ks1 reservoir layer in the top of the Kashirskian sequence is composed of microcrystalline dolomites. The seal includes of polydetritic grainstones and laminated bioclastic packstones with sulfate inclusions. The middle part of the Kashirskian sequence is characterized by a complex interbedding of dolomite and limestone reservoirs with different filtration-volumetric properties and low-permeability rocks (possible seals). The described structural features of the Kashirskian sequence must be taken into account when calculating reserves, as well as when designing horizontal wells and hydraulic fracturing.

References

1. Kirillov A.I., Akhmatdinov F.N., Lozin E.V. et al., Estimation of the efficiency of oil displacement by water from the reservoir rocks of the middle carboniferous fields of Bashkortostan (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2009, no. 11, pp. 96-99.

2. Khisamov R.S., Khazipov R.G., Bazarevskaya V.G. et al., Studying the structure of void space of complex carbonate rocks of the Kashirskian horizon using electric microscanning technique (In Russ.), Geologiya nefti i gaza, 2014, no. 3, pp. 47–53.

3. Mirnov R.V., Sedimentological cyclicity and lithological features of the Kashirskian sequence in the northwestern Bashkortostan (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 7, pp. 79-81, DOI 10.24887/0028-2448-2020-7-79-81.

4. Choquette P.W., Pray L.C, Geologic nomenclature and classification of porosity in sedimentary carbonates, AAPG Bulletin, 1975, V. 54, pp. 207–250, DOI:10.1306/5D25C98B-16C1-11D7-8645000102C1865D

5. Kirkham A., Patterned dolomites: microbial origins and clues to vanished evaporates in the Arab Formation, Upper Jurassic, Arabian Gulf, Geological Society, London, Special Publication, 2004, V. 235, pp. 301–308, DOI:10.1144/GSL.SP.2004.235.01.12

The article considers the features of complex petrophysical modeling of low-permeability Achimov deposits. These deposits are characterized by a typical clinoform structure, extremely low reservoir properties, and heterogeneous oil saturation. Photographs of the core column in UV-light show intervals of different luminescence intensity: strong and weak luminescence, no luminescence, and in combination with a separate coding volume-component model - luminous carbonate interlayers. It is established that oil is contained mainly in luminous layers. Taking into account the frequent alternation of luminous and dark intervals in the reservoir and the uncertainty of their areal distribution, the authors did not considerethe reliability of the prediction of oil-water contact (OWC) as a single horizontal surface for the studied clinoform complex. More likely is the existence of independent oil and water saturated interlayaers above the OWC. In this case, the reservoir rocks identified according to well logging data and characterized by the absence of luminescence (sub-reservoirs), due to low porosity and permeability properties, are not capable of receiving oil at a given capillary pressure and contain mainly bound water and a small amount of free water. It is difficult to identify sub-reservoir intervals only according to well logging data, because reservoir properties and electrical resistivities of luminous and conditionally dark intervals do not differ. The article presents an approach to assessing effective thicknesses and identifying sub-reservoirs, based on the theory of capillary barriers. According to this approach, it is assumed that at the stage of reservoir formation, oil could not overcome the inlet displacement pressure and the rock remained water saturated. For oil-saturated intervals the capillary pressure must exceed the displacement pressure. The inlet displacement pressure is the pressure at which the wetting phase saturation is below 100%. The relationship between the displacement pressure in the water-oil system and permeability was obtained according to the capillary studies data. In petrophysical modeling such an approach means substantiating the dependence of the reservoir cut-offs on the height above the OWC.

References

1. Marinov V.A., Khramtsova A.V., Igol'nikov A.E. et al., Stroenie achimovskoy tolshchi arkticheskikh rayonov Zapadnoy Sibiri (The structure of the Achimov strata of the Arctic regions of Western Siberia), Collected papers “Paleontologiya, biostratigrafiya i paleogeografiya mezozoya i kaynozoya boreal'nykh rayonov” (Paleontology, biostratigraphy and paleogeography of the Mesozoic and Cenozoic boreal regions), Proceedings of online session dedicated to the 110th anniversary of the birth of Corresponding Member of the USSR Academy of Sciences Saks V.N., Novosibirsk, 2021, pp. 125–129.

2. Korolev D.O., Pavlov V.A., Ankudinov A.A. et al., Effective planning and implementation of geomechanical hydrofracturing modeling in conditions of abnormally high reservoir pressure (In Russ.), Karotazhnik, 2021, no. 8 (314), pp. 157–172.

3. Volokitin Ya.E., Khabarov A.V., Baranov V.B. et al., Novye standarty izucheniya mestorozhdeniy – razrez svoimi glazami (New standards for the study of deposits - a cut with your own eyes), Rossiyskie neftegazovye tekhnologii, 2010, URL: https://www.rogtecmagazine.com/wp-content/uploads/2014/09/5.SPD_.pdf

4. Kasatkin V.E., Gil'manova N.V., Moskalenko N.Yu. et al., Analysis of Achimov reservoirs’ texture heterogeneity of Imilorsky deposit when assessing the nature of saturation (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2016, no. 11, pp. 18-23.

5. Kuznetsov A.V., Shalamova V.I., Gil'manova N.V. et al., The experience of building a hydrodynamic model in the conditions of fluid heterogeneity of productive strata of the Imilorsky field (In Russ.), Nedropol'zovanie XXI vek, 2018, no. 6, pp. 146-155.

6. Bol'shakov Yu.Ya., Teoriya kapillyarnosti neftegazonakopleniya (Theory of oil and gas accumulation capillarity), Novosibirsk: Nauka Publ., 1995, 182 p.

7. Afanas'ev Yu.V. Tsivinskaya L.V., Hydrocarbon deposit as a self-organizing system (In Russ.), Geologiya nefti i gaza, 1999, no. 5–6, pp. 28–33.

8.  Tiab D., Donaldson E C., Petrophysics: theory and practice of measuring reservoir rock and fluid transport, Elsevier Inc., 2004, 926 p.

9. Cheremisin N.A., Rzaev I.A., Alekseev D.A., Impact of clay spatial coherence and filtration-capacitive properties on field development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 11, pp. 32–35.

Geological storage of carbon dioxide has been recognized as a necessary technology for environmental sustainability by reducing greenhouse gas emissions in recent years. Currently, there are no active carbon capture, utilisation and storage (CCUS) projects in Russian Federation; however rich international experience has been accumulated in this area. The main purpose of the research is to substantiate regional geological criteria for assessing the territory of the Russian Federation for the prospects for carbon dioxide disposal. Based on the current international and Russian regulatory frameworks for the disposal of carbon dioxide, industrial effluents, toxic waste, and the arrangement and monitoring of underground gas storage facilities, we have proposed criteria for a regional forecast of the territory in order to implement CCUS projects. The territory of the Russian Federation was assessed in terms of suitability for long-term storage of carbon dioxide. For the first time the territory is divided into high-, medium-, low-promising and unpromising. A map for the implementation of CCUS projects on the territory of the Russian Federation was compiled according to the regional level criteria (scale 1: 2500000) in the form of an ArcGis project. Within the Eastern European hydrogeological region, the most promising artesian basins are: Moscow, Severo-Dvinsky, Vetluzhsky, Volga-Khopersky, Volga-Sursky, Kamsko-Vyatsky. Highly promising also includes the Pechora artesian basin, located within the Pechora-Barents sea platform plate. In the West Siberian region these are the Taz-Pur and Irtysh-Ob artesian basins. In the Arctic sector of the East Siberian hydrogeological region, the greatest prospects should be associated with the Pyasino-Yenisei and Balakhna artesian basins. In the southern part, the Putoransky, Nizhne-Tungussky, Katangsky and Priangarsky artesian basins stand out as the most promising.

References

 1. Wallén C.-Ch. et al., Carbon dioxide. Current views and developments in energy/Climate research: edited by Bach W., Crane A.J., Berger A.L., Longhetto A., 2nd Course of the International School of Climatology, Ettore Majorana Centre for Scientific Culture, 1984, 552 p.

2. BP Statistical Review of World Energy 2021, 70th edition, URL: https://www.bp.com/content/dam/bp/business-sites/en/global/corporate/ pdfs/energy-economics/statistical-review/bp-stats-review-2021-full-report.pdf

3. Tang Y, Yang R, Bian X., A review of CO2 sequestration projects and application in China, The Scientific World Journal, 2014, DOI: 10.1155/2014/381854.

4. Aminu M.D., Nabavi S.A., Rochelle C.A., Manovic V., A review of developments in carbon dioxide storage, Applied Energy, 2017, V. 208, pp. 1389–1419, DOI: 10.1016/j.apenergy.2017.09.015.

5. Shukla R., Ranjith P., Haque A., Choi X., A review of studies on CO2 sequestration and caprock integrity, Fuel, 2010, V. 89, no. 10, pp. 2651–2664, DOI: 10.1016/j.fuel.2010.05.012.

6. Khan S.A., The analysis of world projects on catching and a burial place of carbonic gas (In Russ.), Georesursy, 2010, no. 4(36), pp. 55–62.

7. Zahid U, Lim Y, Jung J, Han C., CO2 geological storage: A review on present and future prospects, Korean Journal of Chemical Engineering, 2011, V. 28, pp. 674–685, DOI: 10.1007/s11814-010-0454-6.

8. Li L., Zhao N., Wei W., Sun Y., A review of research progress on CO2 capture, storage, and utilization in Chinese Academy of Sciences, Fuel, 2013, V. 108, DOI: 10.1016/j.fuel.2011.08.022.

9. Bachu S., Review of CO2 storage efficiency in deep saline aquifers, International Journal of Greenhouse Gas Control, 2015, V. 40, pp. 188–202, DOI: 10.1016/j.ijggc.2015.01.007.

10. Dymochkina M.G., Samodurov M.S., Pavlov V.A., Geological potential of carbon dioxide capture and storage of the Russian Federation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 12, pp. 20–23, DOI: 10.24887/0028-2448-2021-12-20-23

11. ISO 27916:2019, Carbon dioxide capture, transportation and geological storage – Carbon dioxide storage using enhanced oil recovery (CO2-EOR), Switzerland, 2019, 64 p.

12. Borevskaya A.V., Gavrilov I.T., Gol'dberg V.M., Gidrogeologicheskie issledovaniya dlya zakhoroneniya promyshlennykh stochnykh vod v glubokie vodonosnye gorizonty (Hydrogeological studies for the disposal of industrial wastewater in deep aquifers): edited by  Antonenko K.I., Chapovskogo E.G., Moscow: Nedra Publ., 1976, 312 p.

13. The Active Faults of Eurasia Database (AFEAD), URL: http://neotec.ginras.ru/index/mapbox/database_map.html

14. USGS (Earthquake Hazards), URL:  https://www.usgs.gov/programs/earthquake-hazards/earthquakes

15. GIS-Atlas OOPT territorii Rossiyskoy Federatsii (GIS-Atlas of specially protected natural territories of the Russian Federation), URL:  http://agssrv1.vsegei.ru/arcgis/rest/services/GisAtlas/oopt_poly/MapServer

The article considers the structural peculiarities of the void space, affecting the filtration properties of volcanogenic-sedimentary rocks of the central zone of the northeastern framework of the Krasnoleninsky arch. A method for permeability coefficient determination is proposed based on standard well logging complex data. The volcanogenic-sedimentary strata are characterized by a complicated composition (presence of cracks, caverns, intergranular pores) and the structural peculiarities (distribution of voids by size of the void space of rocks). These peculiarities reduce the reliability of permeability coefficient determination in interaction with the porosity coefficient. With a constant porosity coefficient value, variations in the permeability coefficient range greatly. The connections between capacitive and filtration properties should be used for more accurate permeability estimation, taking into account the peculiarities of the internal structure of the void space of rocks. Such connections are based on different structural models of void space. The permeability estimation of rocks of the studied strata is made according to the dumbbell model, which describes the void space of rocks as an interconnected system of voids (macrocapillaries) and channels (microcapillaries) connecting them. The model takes into account the differences in equivalent sections (capacitive, filtration, electric) of macro- and microcapillaries, interconnected due to electrohydrodynamic analogy. The ratio of sections is determined by the electric tortuosity of the void space meaning expansion of current electric lines in large voids and narrowing in connecting channels. The values of the permeability coefficients calculated using the dumbbell model approximate the results of the core sample studies well enough. The exception is intensively fractured samples, in which the calculated values of the permeability coefficient are significantly lower than those measured in the core samples.

This permeability coefficient calculation model is applicable to rocks with increased capacitive properties. The properties of the matrix have a decisive effect on the filtration characteristics of such rocks, the void space of which is of crack-cavern-granular type. The main effective capacity in rocks with reduced capacitive properties is represented by cracks and cavities; the matrix is characterized by low filtration and capacitive properties. Open cracks have a decisive effect on the filtration properties of such rocks. Evaluation of their filtration properties was made using the dependence of the permeability coefficient established by hydrodynamic studies on the coefficient of fractured voids determined by well logging.

References

1. Karlov A.M., Usmanov I.Sh., Trofimov E.N. et al., Makroizuchenie neftenasyshchennykh vulkanitov doyurskogo kompleksa Sidermskoy ploshchadi Rogozhnikovskogo mestorozhdeniya (Macro-study of oil-saturated volcanics of the pre-Jurassic complex of the Sidermskaya area of the Rogozhnikovskoye field) Proceedings of X scientific and practical conference “Puti realizatsii neftegazovogo potentsiala KhMAO” (Ways of realization of oil and gas potential of KhMAO), Khanty-Mansiysk, 2007, pp. 295–307.

2. Kropotova E.P., Korovina T.A., Romanov E.A., Fedortsov I.V., Sostoyanie izuchennosti i sovremennye vzglyady na stroenie, sostav i perspektivy doyurskikh otlozheniy zapadnoy chasti Surgutskogo rayona (Rogozhnikovskiy litsenzionnyy uchastok) (The state of knowledge and modern views on the structure, composition and prospects of pre-Jurassic deposits of the western part of the Surgut region (Rogozhnikovsky license area)), Proceedings of IX scientific and practical conference “Puti realizatsii neftegazovogo potentsiala KhMAO” (Ways of realization of oil and gas potential of KhMAO), Khanty-Mansiysk, 2006, pp. 133–146.

3. Shadrina S.V., Kritskiy I.L., The formation of volcanogenic reservoir by hydrothermal fluid  (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2012, no. 8, pp. 18–21.

4. Romm E.S., Strukturnye modeli pustotnogo prostranstva gornykh porod (Structural models of the void space of rocks), Leningrad: Nedra Publ., 1985, 240 p.

5. Dobrynin V.M., Vendelshteyn B.Yu., Kozhevnikov D.A., Petrofizika (Fizika gornykh porod) (Petrophysics (Physics of rocks)), Moscow: Nedra Publ., 1991, 368 p.

6. Akhmetov R.T., Dumbbell-like model of vacuum space of oil and gas natural reservoirs (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2011, no. 5, pp. 31–35.

7. Akhmetov R.T., Kneller L.E., Forecast for absolute permeability of granular reservoirs on the basis of the dumbbell simulation of the void space (In Russ.), Karotazhnik, 2013, no. 7 (229), pp. 75–88.

8. Afanas'ev V.S., The theoretical and experimental validations of the generalized petrophysical model of capillary pressure while hydrocarbon draining in the grained porous medium (In Russ.), Karotazhnik, 2016, no. 11 (269), pp. 50–93.

9. Glebocheva N.K., Telenkov V.M., Khamatdinova E.R., Effusive reservoir capacity space structure from logs and core (In Russ.), Karotazhnik, 2009, no. 6 (183), pp. 3–10.

10. PKrylov A.P., Belash P.M., Borisov Yu.P. et al., Proektirovanie razrabotki neftyanykh mestorozhdeniy (Field infrustructure development), Moscow: Gostoptekhizdat Publ., 1962, 430 p.

11. Krylova O.V., Razrabotka metodiki opredeleniya litologicheskogo sostava i kollektorskikh svoystv vulkanogenno-osadochnykh porod po dannym promyslovoy geofiziki (na primere sredneeotsenovykh otlozheniy mestorozhdeniy Gruzii) (Development of a method for determining the lithological composition and reservoir properties of volcanic-sedimentary rocks based on production geophysics data (on the example of Middle Eocene deposits of Georgian fields)): thesis of candidat of geological and mineralogical science, Groznyy, 1983.

12. Nguyen Kh.B., Geophysical studies of wells in the study of igneous reservoirs of the White Tiger field (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta, 2013, V. 323, no. 1, pp. 27–33.

Maintaining oil production at long-term developed fields requires solving the problem of high production costs. This problem is associated with the need to withdraw significant volumes of produced water and a proportionally high need for injection in order to maintain reservoir pressure. It is noted that a 1% reduction in water cut in production makes it possible to reduce operating costs in oil production by up to 15%. It is shown that the problems of effective development of mature fields are associated with the solution of the optimization problem of distributing fluid production and water injection in the wells system. The authors argue the idea that at the later stages of development, the priority for hydrodynamic modeling should be tools based on solving the inverse problem of hydrodynamics, providing for the widespread use of material balance methods and allowing big data processing. A new concept of combining artificial intelligence methods and a hydrodynamic model is proposed. The concept provides for obtaining a functional relationship between the historical oil production rate and injectivity using a neural network, searching for the maximum oil production and its distribution. At the same time, only one calculation is performed on the hydrodynamic model, which significantly reduces time costs. An example of the application of the proposed technology is given. It is concluded that the set of methodological, mathematical and informational solutions presented in the article will allow formalizing the processes of designing hydrodynamic methods for enhanced oil recovery, clarifying the model for a feasibility study of profitable and technologically recoverable oil reserves.

References

1. Vygon Consulting. Nalogi v neftedobyche: reforma 2020 (Vygon Consulting. Taxes in oil production: reform 2020), URL: https://vygon.consulting/upload/iblock/ 0b6/vygon_consulting_tax_reform_2020.pdf.

2. Kozlova D.V., “Umnaya” dobycha: pochemu tsifrovye tekhnologii uderzhat nizkie tseny na neft' (Smart mining: why digital technologies will keep oil prices low), URL: https://www.forbes.ru/biznes/351129-umnaya-dobycha-pochemu-cifrovye-tehnologii-uderzhat-nizkie-ceny-....

3. Garifulin A.R., Slivka P.I., Gabdulov R.R., “Smart wells“ - System of automated control over oil and gas production (In Russ.), Neftʹ. Gaz. Novatsii, 2017, no. 12, pp. 24–32.

4. Ryabets D.A., Beskurskiy V.V., Brilliant L.S. et al., Production management based on neural network optimization of well operation modes at the BS8 facility of the Zapadno-Malobalykskoye field (In Russ.), Neftegaz.ru, 2019, no. 9, URL: https://magazine.neftegaz.ru/articles/tsifrovizatsiya/455504-upravlenie-dobychey-na-osnove-neyrosete...

5. Patent RU 2 759 143 C1, Method for increasing the efficiency of hydrodynamic methods for increasing the petroleum recovery of a reservoir, Inventors: Brilliant L.C., Zav'yalov A.S., Dan'ko M.Yu., Elisheva A.O., Andonov K.A., Tsinkevich O.V.

6. Patent RU 2 614 338 C1, Method of real-time control of reservoir flooding, Inventors: Brilliant L.S., Komyagin A.I., Blyashuk M.M., Tsinkevich O.V., Zhuravleva A.A.

7. Patent RU 2 565 313 C2, Operations control method for reservoir flooding, Inventors: Brilliant L.S., Smirnov I.A., Komjagin A.I., Potrjasov A.V., Pechorkin M.F., Baryshnikov A.V.

8. Patent RU 2 715 593 C1, Method of operative control of water flooding of formations, Inventors: Brilliant L.S., Zav'yalov A.S., Dan'ko M.Yu.

9. Brilliant L.S., Dulkarnaev M.R., Dan'ko M.Yu. et al., Challenges of efficient brownfield development: architecture of digital solutions in control of well operation conditions (In Russ.), Nedropol'zovanie XXI vek, 2020, no. 4, pp. 98-107.

10. Potryasov A.A., Mazitov M.R., Nikiforov S.S. et al., Management over oil field flooding process at the basis of proxy modeling (In Russ.), Neft'. Gaz. Novatsii, 2014, no. 12, pp. 32-37.

11. Aref'ev S.V., Yunusov R.R., Valeev A.S. et al., Methodical foundations and experience in the implementation of digital technologies for operational planning and management of the operating modes of production and injection wells in the OPR area of the YuV1 reservoir of the Vatjeganskoye deposit of the Povkhneftegaz TPP (OOO LUKOIL-Western Siberia) (In Russ.), Nedropol'zovanie XXI vek, 2017, no. 6, pp. 60-81.

12. Brilliant L.S., Gorbunova D.V., Zav'yalov A.S. et al., Automation of processes for managing the operation modes of injection wells with neural network optimization at the BS8 facility of the Zapadno-Malobalykskoye field (In Russ.), Neftegaz.ru, 2020, no. 2, pp. 52-57.

13. Zarubin A.L., Perov D.V., Ryabets D.A. et al., Automation of neural network optimization processes for water injection at the fields of "OC "Neftisa" JSC (In Russ.), Neft'. Gaz. Novatsii, 2020, no. 8, pp. 40-53.

The paper is focused on innovative technologies of well and reservoir real-time surveillance for both data recording, and further study of the thermo-dynamic processes around the well and the reservoir. In particular, a special role is given to temperature field, the most promising method of cased-hole production logging. Today, such a tool as distributed fiber-optic downhole temperature and acoustic sensors record an enormous amount of information at a high speed, and this is possible in real time. In this regard, there is a need for the development of specialized software that allows for primary processing and interpretation of distributed temperature records by fiber-optic. This need contributed to the activation of the creation of software and methodological support (SMS) of DTS - software aimed at solving the mentioned above tasks: a portal for data documentation and analytical module for interpretation of a distributed temperature records. This paper discusses approaches to the software concept. In addition, some requirements for the composition, structure and principles of operation of such software-analytical products are substantiated and outlined, recommendations are given for their practical use when working with the results of fiber-optic temperature records. Implementation of the presented approaches to increasing the efficiency of oil and gas fields development, namely: clarification and adaptation of the current dynamic model of the field, assess the degree and reasons for the decrease in well productivity, identify the places of water breakthroughs, as well as which hydraulic fracturing ports or wellbore intervals are not flowing. A clear advantage of the proposed concept of data interpretation lies in the fact that the presented fiber-optic technologies are simultaneously elements of instrumental digital control and a digital processing system for geomonitoring processes, capable of providing optimal well control during long-term production.

References

1. Ipatov A.I., Kremenetskiy M.I., Kaeshkov I.S., Buyanov A.V., Experience in the application of distributed fiber optic thermometry for monitoring wells in the company Gazprom Neft (In Russ.), PRONEFTʹ. Professionalʹno o nefti, 2017, no. 3, pp. 55–64.

2. Ramazanov A.Sh., Sadretdinov A.A., The use of simulators for the quantitative interpretation of thermal logs (In Russ.), Karotazhnik, 2014, no. 9, pp. 38–46.

3. URL: https://www.slb.ru/services/wireline/ production_logging/flow_scanner.

4. Ipatov A.I., Andrianovskiy A.V., Voronkevich A.V. et al., Study of seismoacoustic effects in an producing oil horizontal well based on a fiber-optic cable sensor DAS (In Russ.), PRONEFTʹ. Professional'no o nefti, 2021, no. 2, pp. 52–59, DOI: 10.51890/2587-7399-2021-6-2-50-57

5. Aslanyan A., Aslanyan I., Karantharath R. at al., Spectral noise logging integrated with high-precision temperature logging for a multi-well leak detection survey in South Alberta, SPE-175450-MS, 2015, https://doi.org/10.2118/175450-MS

6. Kremenetskiy M.I., Ipatov A.I., Primenenie promyslovo-geofizicheskogo kontrolya dlya optimizatsii razrabotki mestorozhdeniy nefti i gaza (Application of field geophysical control to optimize the development of oil and gas fields), Part II. Rol' gidrodinamiko-geofizicheskogo monitoringa v upravlenii razrabotkoy (Role of hydrodynamic and geophysical monitoring in development management), Moscow – Izhevsk: Publ. of Institute of Computer Science, 2020, 756 p.

The paper considers issues related to the assessment of phase flow rates based on hermohydrodynamic studies of horizontal wells using mathematical modeling of multiphase flow in the well and the reservoir. To increase the productivity of hydrocarbon fields and to solve oilfield problems, it is necessary to take into account the multiphase flow in the wellbore, in particular, to determine the flow characteristics of the phases. That is why much attention has been paid to the study of multiphase flows in production wells recently. The holdups determined by compositional methods, the average volumetric flow rate measured by a spinner, as well as the hydrodynamic model of the flow in the well, make it possible to determine the flow rates of each phase. However, the quality of the data recorded by spinner, especially in low-rate wells, does not always allow their use. Adding a temperature field to the analysis enables unambiguously solution of the phase flow rates determination problem in the absence of data from a spinner. At the same time, for the quantitative interpretation of temperature measurements, a mathematical model of thermal processes in the well and the reservoir is required. Thermohydrodynamic studies interpretation includes a solving of the inverse problem. Thus, in addition to mathematical models, an optimization algorithm is required. The evolution and genetic optimization methods work quite well for the above tasks.

References

1. Lenn K., Kadenkhed D., Sander R., Ashurov V., New developments in the production logging in horizontal wells (In Russ.), Tekhnologii TEK, 2004, no. 5.

2. Flores J.G., Sarica C., Chen T.X., Brill J.P., Investigation of holdup and pressure drop behavior for oil-water flow in vertical and deviated wells, Trans. ASME, 1998, V. 120, no. 8.

3. Flores J.G., Sarica C., Chen T.X., Brill J.P., Characterization of oil-water flow patterns in vertical and deviated wells, SPE-38810-MS, 1997, DOI:10.2118/38810-MS

4. Hasan A.R., Kabir C.S., A simplified model for oil water flow in vertical and deviated wellbores, SPE-54131-PA, 1999, https://doi.org/10.2118/54131-PA.

5. Petalas N., Aziz K., A mechanistic model for multiphase flow in pipes, Journal of Canadian Petroleum Technology, 1998, V. 39(06), DOI: 10.2118/98-39

6. Kabir C.S., Hoadley S.F., Kamal D., Use of flow-pattern-based models for interpreting oil-water flow in production logging, SPE-68468-MS, 2001, DOI:10.2118/68468-MS

7. Shi H., Holmes J., Durlofsky L.J. et al., Drift-flux modeling of two-phase flow in wellbores, SPE-84228-PA , 2005, DOI: 10.2118/84228-PA

8.Shi H., Holmes J., Durlofsky L.J. et al., Drift-flux parameters for three-phase steady-state flow in wellbores, SPE-89836-MS, 2004, DOI: 10.2523/89836-MS

9. Valiullin R.A. et al., The quantitative measurement of inflowing stream composition with the use of distributed moisture meters (In Russ.), Georesursy, 2013, no. 3 (53), pp. 17–21.

10. Taitel Y., Duckler A.E., A model for predicting flow regime transitions in horizontal and nearly horizontal gas-liquid flow, J. AIChE, 1976, V. 22–45, pp. 47–55, DOI:10.1002/AIC.690220105

11. Brill J.P., Mukherjee H., Multiphase flow in wells, SPE Monograph, Henry L. Dogherty Series, V.17, 1999.

Over the past 20 years, many results of scientific research have been published aimed at studying thermohydrodynamic effects in producing and injection wells in steady and unsteady filtration modes.

These works present the technological features of performing thermohydrodynamic well tests and the methodological basis for processing the results of field studies, which reduce uncertainty in determining the filtration properties of the reservoir and productive parameters of wells, including wells with a complex architecture of shanks. However, the information potential of permanent downhole gauges (PDG) is not limited only to the study of these parameters but allows monitoring of such physical and technological parameters of the oil recovery and production process that are not directly measured by PDG. In particular, when monitoring the development of complex oil fields with contact gas reserves and underlying water, it is important to measure not so much the downhole pressure as to determine its optimal value, preventing the formation of gas and water cones. Obviously, the pressure parameter alone does not provide a solution to this problem. It is necessary to control the integral parameter such as gas factor for determining the required downhole pressure value.

The article considers an algorithm for field development control by an indirect parameter - the gas factor, the value of which is calculated on the basis of measured physical and technological quantities such as pressure, temperature and their change over time. The relevance of this approach results from the complexity of instrumental measurement of GF in field conditions associated with the gas separation pressure above atmospheric pressure and the lack of measurement tools for gas flows with droplet liquid.

References

1. Ramazanov A.Sh. et al., Thermal modeling for characterization of near wellbore zone and zonal allocation (In Russ.), SPE-136256-MS, 2010, https://doi.org/10.2118/136256-MS

2. Sadretdinov A.A., Neizotermicheskaya fil'tratsiya szhimaemogo flyuida v sisteme skvazhina – plast (Non-isothermal filtration of compressible fluid in the well-reservoir system): thesis of candidate of physical and mathematical science, Ufa, 2011. 

3. Ramazanov A.Sh., Teoreticheskie osnovy skvazhinnoy termometrii (Theoretical foundations of downhole thermometry), Ufa: Publ. of BashSU, 2017, 112 p., URL: https://elib.bashedu.ru/dl/read/Ramazanov_Teoreticheskie osnovy skvazhinnoj termometrii_up_2017.pdf.

4. Pityuk Yu.A., Davletbaev A.Ya., Musin A.A. et al., Estimation of various temperature effects influencing temperature change near bottomhole formation zone (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “NK “Rosneft'”, 2016, no. 1, pp. 28-34.

5. Fatikhov S.Z., Gimaev A.F., Fedorov V.N., Using of thermal-hydrodynamic methods of layers research in the fields in the Republic of Bashkortostan (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 1, pp. 56–59, DOI: 10.24887/0028-2448-2020-1-56-59

6. Ponomarev A.I., Zaripova K.R., Numerical calculation of unsteady nonisothermal gasflow (In Russ.), Neftegazovoe delo, 2013, no. 3, pp. 228–262, URL: http://ogbus.ru/files/ogbus/authors/PonomarevAI/PonomarevAI_2.pdf

The article is devoted to accounting the scale effect, reservoir heterogeneity and, as a result, improving the quality of integral adaptation in the hydrodynamic modeling of the oil displacement process. The theoretical foundations of the problem of determining the permeability of a productive formation are presented. The weaknesses of the traditional approach to calculating the permeability from porosity, based on laboratory core tests, are shown. The authors note the issue of heterogeneity averaging in the study of the physical properties of the reservoir is more fundamental than the problem of effective average parameters, because as the size of the sample volume increases, the difference between the measured properties in the sample and the infinite volume decreases monotonically to the required accuracy. Based on the hydrodynamic model of one of the oil fields in the Volga-Ural region, it was confirmed that the use of the basic petrophysical dependence of permeability on porosity can lead to unreliable ideas about well flow rates. Due to the analysis and ranking of the input data, using the Python programming language, an algorithm has been implemented to improve the accuracy of estimating the reservoir productivity by taking into account information on the spatial distribution of porosity, which is a reflection of reservoir heterogeneity. The algorithm is based on a series of multivariate calculations of the sector hydrodynamic model of an oil reservoir. This approach allowed obtaining a new permeability-porosity point cloud and correcting the petrophysical curve. In addition, a series of calculations was carried out to assess the sensitivity of the results to the size of the hydrodynamic grid cell using the local cell refinement option. Based on the results of the work performed, it was noted that the presented algorithm makes it possible to more accurately reproduce the integral adaptation of the hydrodynamic model in comparison with the traditional approach, as well as to correct the permeability-porosity trend to improve the reproduction of well productivity, and thereby more correctly accounting the influence of reservoir heterogeneity and the scale effect.

References

1. Olenchikov D.M., Sapozhnikov A.E., Shtin N.A., Chebkasov D.S., Improving reservoir productivity evaluation by considering statistical data about heterogeneity (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “NK “Rosneft'”, 2011, no. 2, pp. 39–42.

2. Gurbatova I.P., Enikeev B.N., Mikhailov N.N., Elementary representative volume in the physics of a reservoir. Part 1. Basic provisions and their physical interpretation (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2018, no. 6, pp. 62–68.

3. Gurbatova I.P., Enikeev B.N., Mikhailov N.N., Elementary representative volume in the physics of a reservoir. Part 2. Scale effects and petrophysical relations (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2018, no. 76, pp. 65–72.

4. Nazarova L.N., Kazetov S.I., Ganiev A.L., Urazakov K.R., The method of calculation of well productivity in heterogeneous permeability reservoirs (In Russ.), Neft'. Gaz. Novatsii, 2018, no. 4, pp. 51–55.

5. Nurgaliev R.Z., The method of recovery of "porosity-permeability" petrophysical relationship based on the average values of a heterogeneous reservoir properties (In Russ.), Avtomatizatsiya, telemekhanizatsiya i svyaz' v neftyanoy promyshlennosti, 2017, no. 3, pp. 47–79.

6. Kozhin V.N., Makhmutov A.A., Gilmanova R.Kh., Sarvaretdinov R.G., Perfection of the method of permeability cube building with account of formations’ heterogeneity while 3D modeling (In Russ.), Avtomatizatsiya, telemekhanizatsiya i svyaz' v neftyanoy promyshlennosti, 2015, no. 4, pp. 26–28.

7. Papukhin S.P. Sarvaretdinov R.G., Mel'nikov M.N., Substantiation of the choice of the method for constructing the petrophysical relationship between porosity and permeability (In Russ.), Neftepromyslovoe delo, 2008, no. 1, pp. 14–20 .

8. Sarvaretdinov R.G., Sagitov D.K., The use of a geological and mathematical model of a reservoir when comparing the average values of porosity and permeability of layers of different heterogeneity (In Russ.), Avtomatizatsiya, telemekhanizatsiya i svyaz' v neftyanoy promyshlennosti, 2008, no. 10, pp. 15–20.

The process of studying the hydrophobization of carbonate rock with organic acids includes the preparation of samples and their treatment with compositions of carboxylic and naphthenic acids. To reproduce reservoir conditions, adsorption was carried out at a temperature of 70 °C. During the study, the time of contact of the rock with acids was varied (1, 14 days); the operation of washing with toluene after aging in acids was used. The assessment of the change in the wetting properties was carried out by the static contact angle by two methods: scanning electron microscopy in the "natural environment" mode (ESEM) and sessile drop method on a DSA30S device from Kruss. The correctness of the contact angle measurement was confirmed on standard samples: glass (hydrophilic) and teflon (hydrophobic). A change in the wettability of carbonate plates from hydrophilic to hydrophobic after aging in solutions of palmitic and stearic acids has been achieved. In the case of palmitic acid, the wetting angle increases as the holding time increases. Washing samples with toluene after aging in acid has a hydrophilizing effect - the contact angle is reduced by 30% compared to samples without washing. It is possible that toluene washes away some of the acid molecules that have reacted with the molecules adsorbed on the rock surface and formed a monolayer. The fact of acid adsorption on the rock surface was confirmed by the method of pyrolitic two-dimensional chromatography – mass spectrometry (pyro-GC-GC-MS). An increase in the holding time in palmitic acid leads to an increase in the concentration of palmitate anions detected in the products of rock pyrolysis. After 14 days of exposure, a signal of decay products of aggregates of the palmitic acid molecule was recorded, which makes it possible to assume layer-by-layer adsorption of the acid on the rock surface. The obtained results became the basis for the method development for controlled calcite aging with solutions of carboxylic acids.

References

1. Kuramshin R.M., Chernitskiy A.V., Gula E.V., Differential estimation of oil reserves based on carbonate reservoir classification (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 5, pp. 48–50, DOI: 10.24887/0028-2448-2019-5-48-50

2. Gomari S.R., Hamouda A.A., Effect of fatty acids, water composition and pH on the wettability alteration of calcite surface, Journal of Petroleum Science and Engineering, 2006, V. 50, pp. 140–150, DOI:10.1016/j.petrol.2005.10.007

3. Fernø M.A., Torsvik M., Haugland S., Graue A., Dynamic laboratory wettability alteration, Energy Fuels, 2010, V. 24, pp. 3950–3958, DOI:10.1021/ef1001716

4. Sachdeva J.S., Sripal E.A., Nermoen A. et al., A laboratory scale approach to wettability restoration in chalk core samples, Proceedings of E3S Web Conf. (SCA 2018), 2019, V. 89, DOI: 10.1051/e3sconf/20198903003

5. Kumar S., Burukhin A.A., Cheremisin A.N., Grishin P.A., Wettability of carbonate reservoirs: effects of fluid and aging, SPE-201834-MS, 2020, DOI: 10.2118/201834-MS

6. Thomas M.M. at al., Adsorption of organic compounds on carbonate minerals: 1. Model compounds and their influence on mineral wettability, Chemical Geology, 1993, V. 109, pp. 201–213, DOI: 10.1016/0009-2541(93)90070-Y

7. Graue A., Aspenes E., Bognø T. et al., Alteration of wettability and wettability heterogeneity, Journal of Petroleum Science and Engineering, 2002, V. 33(1–3), pp. 3-17, DOI: 10.1016/S0920-4105(01)00171-1

8. Buckley J.S., Liu Y., Monsterleet S., Mechanisms of wetting alteration by crude oils, SPE-37230-PA, 1998, DOI: 10.2118/37230-PA

9. Mihajlović S., Vučinić D., Sekulić Ž., Milićević S., Kolonja B., Mechanism of stearic acid adsorption to calcite, Powder Technology, 2013, V. 245, pp. 208–216, DOI: 10.1016/j.powtec.2013.04.041

10. Ivanova A., Cheremisin A.N., Khayrullin M., Sansiev G., Microstructural imaging and characterization of organic matter presented in carbonate oil reservoirs, SPE-195456-MS, 2019, DOI: 10.2118/195456-MS

11. Zimon A.D., Adgeziya zhidkosti i smachivanie (Liquid adhesion and wetting), Moscow: Khimiya Publ., 1974, 416 p.

12. Mihajlović S., Sekulić Ž., Daković A. et al., Surface properties of natural calcite filler treated with stearic acid, Ceramics-Silikaty, 2009, V. 53, pp. 268–275.

This paper presents the results of optimisation of new projects search and assessment process in Zarubezhneft JSC by developing of information system that allows to organize a single digital space with data of evaluation, monitoring the status, comparing of projects, and managing portfolio. The main point of growth of efficiency of oil and gas companies is not only the ability to operate existing assets (increasing production, optimizing and / or reducing costs, new technologies, etc.), but also acquisition of new ones. Zarubezhneft JSC has a strategic goal to increase annual level of production from oil and gas projects by more than 12 million tonnes of oil equivalent by 2030. Achieving this goal is impossible without expanding the Company's current portfolio by entering or acquiring new projects. To solve this problem, in 2018, Zarubezhneft JSC initiated an IT project to digitalize the process of searching and evaluating new projects, which meets the numerous strategic interests of the Company. It was created a concept and Nestro Terra information system. Nestro Terra is an information system that has database for storage and processing of evaluation results of new projects. System also allows to get the necessary up-to-date information about projects, monitor current state of processes and perform feasibility benchmarking. In the period 2019 - 2021 the Company managed to enter a number of projects in the Russian Federation and abroad (Egypt, Indonesia, Vietnam), which are at different stages of the life cycle (geological exploration, Greenfield, Brownfield), as well as actively using information system Nestro Terra.

The article describes the methodology for automating the design process of pile foundations using the Svaya-SAPR Pro software. The proposed method of automating the design process makes it possible to perform calculations and select optimal solutions for pile foundations. The application of Svaya-SAPR Pro reduces the complexity and timing of design, reduces the risk of errors when performing a large number of calculations. When performing a technical and economic comparison of options for the implementation of pile foundations, Svaya-SAPR Pro allows to reduce the cost of infrastructure projects. The article presents the features of calculations of pile foundations in frozen soils, which were not included in the official edition of SP 25.13330.2020 and presented by the N.M. Gersevanov Research Institute in the framework of the technical expertise of the local regulatory document Rosneft Oil Company, which was named "Design features of pile foundations". The technology was developed in a subsidiary of Rosneft Oil Company - NK Rosneft - NTC LLC and entered into a single line of the Company's software. «Svaya-SAPR Pro» application based on the test results was recommended by the N.M. Gersevanov Research Institute for performing calculations of foundations and pile foundations according to SP 24.13330.2021 and SP 25.13330.2020. The method presented in the article for optimizing capital costs using the Svaya-SAPR Pro software allows to select the most cost-effective technical solution for each pile in an automated mode, as well as to reduce capital costs by up to 15% of the cost of the projected foundations and up to 20% of the labor costs for design without reducing the mechanical reliability of the projected objects.

References

1. Gilev N.G., Zenkov E.V., Poverennyy Yu.S. et al., Optimization of capital costs for pile foundations during construction of oil and gas production facilities on permafrost soils (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 11, pp. 46–49, DOI: 10.24887/0028-2448-2019-11-46-49

2.  Certificate of official registration of the computer program no. 2020618505 “Svaya-SAPR Pro”, Authors: Medyanik S.S., Kesiyan G.A, Dubrov A.D., Zenkov E.V., Zagumennikova A.V., Poverennyy Yu.S., Fedoseenko V.O., Gilev N.G.

3. Poverennyy Yu.S., Dubrov A.D., Gilev N.G. et al., Application of a digital model of a linear object for the design of pipelines in the conditions of construction on permafrost soils  (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 8, pp. 106–109, DOI: 10.24887/0028-2448-2020-8-106-109.

4. Certificate of official registration of the computer program no. 2021616474 “TsMLO”, Authors:  Dubrov A.D., Poverennyy Yu.S., Gilev N.G., Zenkov E.V., Yargunina A.O.

5. Nazarkin D.S., Filimonov A.A., Lipikhin D.V. et al., The use of a neural network for geotechnical monitoring at oil and gas facilities located in the far north (In Russ.), Neft'. Gaz. Novatsii, 2020, no. 10, pp. 78–82.

The article presents the comparison of the results obtained during the assessment of the field water-oil emulsion retention time in the apparatus settling zones at the first (three-phase separators) and second (horizontal tank/vertical steel tank) dehydration stages of two oil treatment plant (OTP-1, OTP-2) of one of the fields in Eastern Siberia. Retention time was determined on the basis of oil companies standards with due regard for the oil physico-chemical properties; results of the water-oil emulsion breakage simulation within the framework of laboratory research; calculation performed using the design parameters; and parameters of current operation mode of existing facilities. The advantages and disadvantages of each of the retention time assessment methods are discussed. The water-oil emulsion breakage under laboratory conditions was simulated using the ‘bottle test’ method. The calculation of disperse phase drop average diameter at the apparatus inlet/outlet and required retention time at the first and second dehydration stages of OTP was performed with different methods such as the water-oil emulsion physico-chemical properties, flow hydrodynamic parameters, and existing empirical and semiempirical dependences. Based on the comparison of the retention times obtained by experimental method and calculation with the current operation process services of abovementioned installations, it was concluded that it is possible to use each of methods when designing oil treatment facilities. As a result it was concluded that, at present, the simulation of emulsion separation under laboratory conditions is the most reliable method for forecasting process conditions necessary for oil treatment, and the method based on calculations is a prospecting one and may be applied provided that the disperse phase drop enlargement processes will be added to the calculation.

References

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2. Xia Lixin, Lu Shiwei, Cao Guoying, Stability and demulsification of emulsions stabilized by asphaltenes or resins, Journal of Colloid and Interface Science, 2004, V. 271 (2), pp. 504-–506.

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14.Tyurin, M.P., Safonov R.A., Iamonova M.M., Aparushkina M.A., Platonova O.V., Separation of stable emulsions in a jet apparatus (In Russ.),  Tekhnologiya tekstil'noy promyshlennosti, 2008, no. 3 (308), pp. 120-123.

The possibility of changing the rheological properties of high-paraffin low-resin oil due to hydro-pulse cavitation treatment (HCT) has been investigated. A mechanism has been proposed to explain the change in the structure of complex structural units (CSU) of oil at HCT. The simulation of the oil flow in the ANSYS CFX software package has been performed to determine the hydrodynamic parameters and cavitation numbers in a hydrodynamic cavitator (HC) with Venturi tubes and in a radial-type rotor-stator device (RSD) implementing HCT in liquids. The calculation of the hydrodynamic cavitation number based on the simulation results indicates developed cavitation in the oil flow in both HC and RSD. Specific energy consumption for oil processing in HC is 1.5 times lower than in RSD. It is assumed that HCT effects lead to the destruction of supramolecular bonds between CSU, and also destroy CSU. When paraffin crystals are destroyed, their specific surface area and, consequently, the surface energy increase. Paraffins form the core of the CSU, and the HCT of oil causes the destruction of paraffin crystals, resins are distributed between solid particles, loosen the crystal structure, adsorb on grain surfaces and change the structure of paraffin crystal associates. The adsorption of resins on destroyed paraffin crystals prevents their aggregation. Processing of high-paraffin low-resin oil in HC and RSD has shown their high efficiency in improving its rheological characteristics. After a single oil treatment in RSD, the amount of thixotropy energy and the viscosity of the oil decreased by an average of 1.5 times. After a single treatment of oil in the HC, the value of the thixotropy energy and the viscosity of the oil decreased by an average of 2 times. When processing in RSD and HC, the specific energy costs for oil processing are significantly less compared to the change in thixotropy energy.

References

1. Sunagatullin R.Z., Kutukov S.E., Gol'yanov A.I. et al., Control of oil rheological properties by exposure to physical methods (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 1, pp. 92-97, DOI: 10.24887/0028-2448-2021-1-92-97

2. Xuedong Liu at al., Investigation of amplification process of heavy oil viscosity reduction device based on jet cavitation using lab experimental and numerical simulation method, Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021, June, DOI: 10.1080/15567036.2021.1940388

3. Omel'yanyuk M.V., Ukolov A.I., Pakhlyan I.A., Investigation of the processes of cavitation fl ow for energy-saving and environmentally friendly technologies in the oil and gas industry (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 12, pp.128-130, DOI: 10.24887/0028-2448-2021-12-128-130

4. Promtov M.A. et al., The influence of hydropulse processing on rheological oil parameters (In Russ.), Vestnik Tambovskogo gosudarstvennogo tekhnicheskogo universiteta, 2020, V. 26, no. 2, pp. 243–253, DOI: 10.17277/vestnik.2020.02.pp.243-253

5. Promtov M.A. et al., Change of rheological parameters of high-paraffin oil under multi-factor impact in a rotor-stator device (In Russ.), Problemy sbora, podgotovki i transporta nefti i nefteproduktov, 2020, no. 5(127), pp. 76-88, DOI: 10.17122/ntj-oil-2020-5-76-88

6. Promtov M.A. et al., Estimation of energy costs when processing high-paraffinic oil in rotary impulse apparatus (In Russ.), Vestnik Tambovskogo gosudarstvennogo tekhnicheskogo universiteta, 2021, V. 27, no. 4, pp. 576–584, DOI: 10.17277/vestnik.2021.04.pp.576-584 

7. Torkhovskiy V.N. et al., Transformation of short-chain n-alkanes under treatment of hydrodynamic cavitation (In Russ.), Tonkie khimicheskie tekhnologii, 2017, V. 12, no. 5, pp. 65 – 70, DOI:10.32362/2410-6593-2017-12-5-65-70

8. Torkhovskiy V.N. et al., Transformation of alkanes under treatment of single impulse of hydrodynamic cavitation. II. Behaviour of medium-chain alkanes C21–C38 (In Russ.), Vestnik MITKhT im. M. V. Lomonosova, 2014, V. 9, no. 4, pp. 59 – 69.

9. Yakimenko K.Yu., Vengerov A.A., Brand A.E., Application of hydrodynamic cavitation treatmentof high-viscosity oils for the purpose of increase of efficiency of transportation (In Russ.), Fundamental'nye issledovaniya, 2016, no. 5–3, pp. 531–536.

10.  Anufriev R.V., Volkova G.I., Yudina N.V., Influence of ultrasonic treatment on structural-mechanical properties of oil and sedimentation (In Russ.), Neftekhimiya = Petroleum Chemistry, 2016, V. 56, no. 5, pp. 454–460.

11. Kondrasheva N.K., Baytalov F.D., Boytsova A.A., Comparative assessment of structural-mechanical properties of heavy oils of timano-pechorskaya province (In Russ.), Zapiski Gornogo instituta, 2017, V. 225, pp. 320–329. 

12. Kutukov S.E., Chetvertkova O.V., Gol'yanov A.I., Gidravlicheskaya kharakteristika truboprovoda na vysokovyazkoy nefti (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2021, V. 11, no. 1, pp. 32–39, DOI: 10.28999/2541-9595-2021-11-1-32-39

The article gives an overview of the properties and reliability of butadiene-acrylonitrile rubber sealant. The sealant has two parts, while the front edge has a special strengthening (reinforcement) that provides resistance while working under pressure. The back edge is more elastic, which is required to increase the tightness of the contact with the pipe wall. Both components are welded together, working as a whole part. It is a well-known fact that when the temperature goes up, the rubber strength goes down. Therefore, at a high temperature the sealant may disintegrate due to its reduced strength parameters. Since the sealant consists of two parts, a transition from a reinforced to the non-reinforced metal takes place in the working area. This transition becomes a tension concentrator, and locally, their levels may go well above the strength limit of the elastomeric sealant. This will lead to the subsequent disintegration of the sealant and peeling of the two edges from one another. The other aim of this article is to evaluate the reliability and critical parameters of the sealant at increasing temperatures and pressure changes to determine the possible safe operating conditions. The article presents laboratory research of the physical and mechanical properties of the elastomer before and after operation. Optimal work modes were identified. Their reliability parameters were evaluated in the course of operation based on the tension field calculations. Studies of increased temperature impact on the sealant strength were conducted. The aftereffects of the reinforcement grid displacement worth several millimeters against the computational position were measured. The finite elements method was used for the analysis.

References

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