The paper highlights the lithological characteristics of apogranite rocks in the zone of tectonization and generation of hydrocarbons. This work is devoted to the study the reservoir properties of an unconventional oil reservoir. The main goal of the work is to assess and visualize the filtration-capacitive characteristics of apogranite tectonites. Oil saturation (85%) of object is confined to the zone of dynamometamorphic transformation of granite. The main lithotype and reservoir in the oil saturation zone is apagranitic tectonite. By the type of fluid storage capacity the reservoir is fractured-cavernous-porous. The main cavitation is intragranular, confined to altered feldspar grains. In the classification this type of reservoir refers to unconventional metamorphic reservoirs with a complex fluid filtration system. In the volume of a sample-cylinder porosity depends on the number of oil slicks, which are mainly confined to grains of altered feldspars, and permeability depends on on the number and opening of fractures. The maximum porosity values are confined to areas with the maximum intensity of oil saturation glow in ultraviolet light. Maximum values of permeability are observed in the crushing zones. The lowest values of porosity are observed in the zones of mylonitization, where areas with oil saturation are single. In sample-cylinders with permeability of less than 1·10-3 mkm2 oil saturation spots are not connected by conductive fracturing. In sample-cylinders with values greater than 1·10-3 mkm2 permeabitity increases depending on fractures connectivity and opening. In the crushing zone, the permeability values increase by 1-2 orders of magnitude, the porosity values by 1-2 units. The permeability in the sample-cylinders from the monolithic sections of the rock reflects the low productivity of these rocks, confirmed by reservoir testing data.

References

1. Trofimova E.N.et al., Granity. Tektonizatsiya, UV-zarozhdenie, neftenasyshchenie (po materialam izucheniya kerna na mestorozhdeniyakh PAO “Surgutneftegaz”) (Granites. Tectonization, hydrocarbon generation, oil saturation (based on the study of core samples at the fields of “Surgutneftegas” PJSC)), Proceedings of XXII scientific and practical conference “Puti realizatsii neftegazovogo potentsiala KhMAO” (Ways of realization of oil and gas potential of KhMAO), Khanty-Mansiysk: IzdatNaukaServis Publ., 2019, Part 2, pp. 178-206, URL: http://www.crru.ru/smi.html

2. Trofimova E.N.et al., Granity. Tektonizatsiya, UV-zarozhdenie, neftenasyshchenie (po materialam izucheniya kerna PAO “Surgutneftegaz”) (Granites. Tectonization, hydrocarbon generation, oil saturation (based on the study of core samples of “Surgutneftegas” PJSC)), URL: https://oil-industry.net/SD_Prezent/2019/10/Новикова_Сургутнефтегаз.pdf

3. Trofimova E.N.et al., Granity. Tektonizatsiya, UV-zarozhdenie, neftenasyshchenie (po materialam izucheniya kerna PAO “Surgutneftegaz”) (Granites. Tectonization, hydrocarbon generation, oil saturation (based on the study of core samples of “Surgutneftegas” PJSC)), Proceedings of XIX scientific-practical conference “Geologiya i razrabotka mestorozhdeniy s trudnoizvlekaemymi zapasami” (Geology and development of deposits with hard-to-recover reserves), Moscow: Neftyanoe khozyaystvo Publ., 2020, pp. 138–150, URL: https://www.elibrary.ru/item.asp?id=43062003

4. Trofimova E.N.et al., Apogranitovye tektonity. Petrofizicheskie parametry (po materialam izucheniya kerna PAO “Surgutneftegaz”) (Apogranitic tectonites. Petrophysical parameters (based on the materials of the study of the core of Surgutneftegaz PJSC)), URL: https://oil-industry.net/SD_Prezent/2022/11/Тектониты_ПФП%20.pdf

The paper examines the verification of existing hypotheses about the structure of thin-layered reservoirs at a number of large deposits of Rosneft Oil Company, located throughout the entire area of Western Siberia. One of the tasks of the work is to verify these ideas about the composition and properties of "clay" elements of textural heterogeneity. Historically, it was believed that clay interlayers inside thin-layered plasto-intersections are interlayers of clays, but later researchers began to express opinions that these interlayers are clined siltstones with a low proportion of pelitic fraction and may contain hydrocarbons. Another important aspect is the degree of uniformity of the sand component of textural heterogeneity, which in classical methods of well logging data interpretation is accepted as homogeneous and isotropic. In addition, textural heterogeneity at some level can significantly affect the anisotropy of permeability, which can significantly affect the processes of vertical migration of hydrocarbons and their accumulation in reservoir rocks. The work analyzes in detail the Vikulov, Achimov, Jurassic deposits and deposits of the Tanopchin formation. The results of unique studies of properties on cubic core samples, non-standard "pieces" from the intervals of thin layering and photo processing are presented. At the same time, these studies are of a massive nature. This allowed us to conclude about the presence of three textural components in reservoir formations: homogeneous coarse and medium-grained sandstone with maximum permeability values for the sample, homogeneous fine-grained sandstones and siltstones, micro-layered clay siltstones. It is shown that such alternation must be taken into account in petrophysical modeling.

References

1. Akin’shin A.V., Povyshenie tochnosti opredeleniya podschetnykh parametrov teksturno-neodnorodnykh peschano-alevrito-glinistykh kollektorov po dannym geofizicheskikh issledovaniy skvazhin (na primere vikulovskikh otlozheniy Krasnoleninskogo svoda) (Improve the accuracy of calculation parameters of texture inhomogeneous sand-silt-clay collectors according to well logging (for example, Vikulov sediments of Krasnoleninsk arc)): thesis of candidate of geological and mineralogical science, Tyumen, 2013.

2. Isakova T.G., D’yakonova T.F., Nosikova A.D. et al., New notions of vikulovskaya series reservoir model in the area of Krasnoleninskoye field (Western Siberia) (In Russ.), Vestnik Moskovskogo universiteta. Seriya 4: Geologiya, 2020, no. 3, pp. 66-74. DOI: https://doi.org/10.33623/0579-9406-2020-3-66-74

3. Zhizhimontov I.N., Makhmutov I.R., Evdoshchuk A.A., Smirnova E.V., Heterogeneous saturation cause analysis during petrophysical modeling of low permeability Achimov deposits (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 3, pp. 30-35, DOI: 10.24887/0028-2448-2022-3-30-35

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. Thomas E.C., Stieber S., The distribution of shale in sandstones and its effect on porosity, Proceedings of SPWLA 16th Annual Logging Symposium, 1975, 15 p.

6. Dobrynin V.M., Usovershenstvovanie geofizicheskikh metodov promyshlennoy otsenki produktivnykh kollektorov Zapadnoy Sibiri (Improvement of geophysical methods for industrial evaluation of productive reservoirs in Western Siberia), Moscow: Publ. of Gubkin Institute, 1980, 193 p.

The study of the Earth's sedimentary cover by seismic exploration at depth of 6-10 km, in the conditions of salt-dome tectonics, is non-trivial task. Technical capabilities for excitation and registration of seismic signal in land seismic exploration are limited because salt deposits are characterized by the powerful absorbing properties. This makes it difficult to study the sedimentary strata of rocks under many kilometers of salt domes. Therefore, in order to successfully solve the set geological tasks, it is important to correctly select optimal processing sequence of available seismic data. With help of one of domestic software processing on the example of area with salt-dome tectonics, the article discusses the main steps for building a depth-velocity model. As is known, the processing and interpretation of seismic data involve the solution of an inverse kinematic task. Since the hodographs of reflected waves cannot be accurately described by hyperbola under conditions of complex geological subsurfaces, the data are summed out of phase, which makes it difficult to determine the time. Under these conditions, the sequence of procedures, known as the standard time processing graph, which assumes the hyperbolicity of the hodographs, does not allow solving the inverse kinematic task with the required accuracy. Therefore, it was decided to use a sequence divided into two main stages. The first is preprocessing (signal processing with maximum preservation of the original wave field and the shape of the hodographs). The second is the construction of an image of the subsurfaces (depth-velocity model by the method of kinematic-dynamic transformation and migration of seismic data in the deep domain). It is shown that the use of this approach to build a processing graph made it possible to obtain a high-quality seismic image of the subsurfaces and successfully to solve the geological tasks in one of the licensed areas of Orenburgneft JSC in Saratov Region.

References

1. Glogovskiy V.M., Langman S.L., Properties of the solution of the inverse kinematic seismic task (In Russ.), Tekhnologii seysmorazvedki, 2009, no. 1, pp. 10–17.

2. Glogovskiy V.M., Meshbey V.I., Tseytlin M.I., Langman S.L., Kinematiko-dinamicheskoe preobrazovanie seysmicheskoy zapisi dlya opredeleniya skorostnogo i glubinnogo stroeniya sredy (Kinematic-dynamic transformation of a seismic record to determine the velocity and depth structure of the medium), Proceedings of the 2nd scientific seminar of the CMEA member countries on petroleum geophysics, Part 1. Seysmorazvedka (Seismic exploration), Moscow: Publ. of CMEA, 1982, pp. 327–331.

3. Kaplan S.A., Lebedev E.B., Finikov D.B., Shalashnikov A.V., Pryamye zadachi v obrabotke i interpretatsii seysmicheskikh dannykh (Direct problems in the processing and interpretation of seismic data), Proceedings of 7th international geological and geophysical conference and exhibition “Sankt-Peterburg 2016. Cherez integratsiyu geonauk – k postizheniyu garmonii nedr” (St. Petersburg 2016. Through the integration of geosciences - to comprehend the harmony of the bowels), St. Petersburg, 11-14 April 2016.

4. Kozhin V.N., Reytyukhov K.S., Troshkin S.V. et al., High-quality planning of field seismic works as one of the factors for the successful implementation of the geological exploration program (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 10, pp. 38-41, DOI: 10.24887/0028-2448-2021-10-38-41

Based on structural and textural features of rocks of volcanogenic-sedimentary strata, their mineral composition, genesis and secondary transformations, 11 petrological types of rocks are identified in the article. Regularities of changes in their chemical, mineral composition, filtration-capacitive properties, mineral and bulk density, acoustic and electrical properties, natural radioactivity and nuclear-physical parameters depending on genesis and secondary transformations have been studied. The need to take into account the identified patterns in geological interpretation of results of well logging is shown. Porosity and permeability increase in sequence: lava of massive texture – lava with voids – volcanic-sedimentary – volcanoclastic rocks. The influence of secondary transformations can both improve and worsen the permeability and capacitance characteristics. The mineral composition of the studied deposits is represented by quartz, potassium feldspar, plagioclase, chlorite, illite, mixed-layer formations, calcite, siderite. The content of quartz, potassium feldspar in naturally reduced from acidic differences to ultramafic. With an increase in the content of dark-colored minerals, the content of chlorite and calcite increases. Secondary processes contribute to the reduction of feldspars as result of their destruction and replacement with post-magmatic minerals. Variations in mineral composition have a significant impact of the density, acoustic and nuclear-physical characteristics of the studied deposits. The electrical resistance of rocks (in addition to porosity and water saturation) depends on the structure of the void space and secondary transformations. Fracturing, clay minerals, zeolites, pyrite reduce electrical resistance. The reduced absorption capacity increases with an increase in clay content from volcanogenic to volcanogenic-sedimentary and sedimentary rocks. The total radioactivity and content of potassium, uranium, and thorium decrease in a series: acidic volcanogenic rocks – volcanogenic-sedimentary deposits – sedimentary deposits - mafic volcanogenic rocks. In acidic volcanogenic rocks radioactivity and potassium content increase in accordance with the change in the type of secondary processes from albitization, digestion carbonatization to chloritization, the development of mixed-layer formations, peletization-illitization and to microclinization. In the same direction, the ratios of thorium to potassium, uranium to potassium decrease.

References

1. 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.

2. Sokolova T.F., Nekrasova T.V., Osobennosti izucheniya vulkanogenno-osadochnykh porod metodami GIS (na primere otlozheniy Zapadnoy Kamchatki) (Features of the study of volcanogenic-sedimentary rocks by well logging methods (on the example of Western Kamchatka deposits)), Proceedings of 10th EAGE science and applied research conference on oil and gas geological exploration and development “Geomodel 2008”, Moscow, 2008, pp. 716–719, DOI: https://doi.org/10.3997/2214-4609.201404426

3. Frolova Yu.V., Ladygin V.M., Rychagov S.N., Petrofizicheskie preobrazovaniya vulkanogennykh porod pod vozdeystviem gidrotermal'nykh protsessov (Petrophysical transformations of volcanogenic rocks under the influence of hydrothermal processes), Materialy IV All-Russian Symposium on Volcanology, Petropavlovsk-Kamchatskiy, 22–27 September 2009, Petropavlovsk-Kamchatskiy, 2009, pp. 821–824.

4. Enikeev B.N., Some petrophysical aspects of the interpretation of volcanic rocks and their weathering crusts, Proceedings of 7th EAGE Conference & Exhibition Understanding the Harmony of the Earthʼs Resources through Integration of Geosciences, Saint Petersburg, April 11–14, 2016, DOI: https://doi.org/10.3997/2214-4609.201600222

5. . Korovina T.A., Kropotova E.P., Romanov E.A., Shadrina S.V., Geologiya i neftenasyshchenie v porodakh triasa Rogozhnikovskogo LU. Regional'nye seysmologicheskie i metodicheskie predposylki uvelicheniya resursnoy bazy nefti, gaza i kondensata, povyshenie izvlekaemosti nefti v Zapadno-Sibirskoy neftegazonosnoy provintsii (Geology and oil saturation in the Triassic rocks of the Rogozhnikovsky license area. Regional seismological and methodological prerequisites for increasing the resource base of oil, gas and condensate, increasing oil recoverability in the West Siberian oil and gas province), Collected papers “Sostoyanie, tendentsii i problemy razvitiya neftegazovogo potentsiala Zapadnoy Sibiri” (The state, trends and problems of the development of oil and gas potential of Western Siberia), Proceedings of mezhdunarodnoy akademicheskoy konferentsii, Tyumen, 2006, pp. 138–142.

6. 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.

7. Kropotova E.P., Korovina T.A., N Gil'manova.V., Shadrina S.V., Usloviya formirovaniya zalezhey uglevodorodov v doyurskikh otlozheniyakh na Rogozhnikovskom litsenzionnom uchastke (Conditions for the formation of hydrocarbon deposits in pre-Jurassic sediments at the Rogozhnikovsky license area), Proceedings of X scientific and practical conference “Puti realizatsii neftegazovogo potentsiala KhMAO” (Ways of realization of oil and gas potential of KhMAO), Khanty-Mansiysk 13–17 November 2007, Ekaterinburg: IzdatNaukaServis Publ., 2007, pp. 372–383.

8. Maleev E.F., Vulkanity (Volcanics), Moscow: Nedra Publ., 1980, 240 p.

9. 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.

10. Efimov V.A., The nuclear physics characteristic of volcanogenic rocks (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2006, no. 8, pp. 108–110.

11. Kondakov A.P., Efimov V.A., Dobryden' S.V., Reservoirs identifying in the volcanogenic-sedimentary rocks of the northeast edge of Krasnoleninskiy

Data management is the whole new level of production process management and making managerial decisions based on data analysis performed by information (IT) systems. A characteristic feature of recent developments in digital and intelligent petroleum fields is the introduction of information and communication technologies throughout the production cycle. Application of digital tools enables progressive, competitive business development and lays the foundations for digital economy development. The digital economy is the basis for creation of whole new business models, capable of setting a new paradigm for the development of the state, economy and the entire society. Within the scope of TATNEFT innovation strategy the Company IT sector has faced the task of data consolidation in a common information space and teaching the systems to interact with each other at levels well beyond data analysis; particularly, provision of recommendations, contingency warning and managerial decision making. For this purpose, reengineering of production processes using modern IT solutions is currently underway. A project aimed at creation of a corporate information system for comprehensive automation of business and production processes in well construction (AIS Drilling) was implemented. Under the scope of this project well construction processes were imported to the common digital space. In particular, the process of well design selection based on the analysis of collected data and well design principles with account of inherent field characteristics was automated. The AIS Drilling is implemented on Russian 1C: Enterprise platform eliminating the dependence on foreign software tools

References

1. Eremin N.A., Dmitrievskiy A.N., Tikhomirov L.I., The present and future of intellectual deposits (In Russ.), Neft'. Gaz. Novatsii, 2015, no. 12, pp. 45–50.

2. Eremin N.A., Chernikov A.D., Sardanashvili O.N. et al., Digital well construction technologies. Creation of a high-performance automated system for preventing complications and emergencies during the construction of oil and gas wells (In Russ.), Neftegaz.RU, 2020, no. 4, pp. 38–50.

Nowadays the oil production level is in decline because the oil reserves of the largest oil places are depleted. Therefore, the main prospects for increasing of the oil production level are associated with the development of low-permeability reservoirs with tight oil reserves. The Priobskoye field is currently one of the largest unconventional reservoirs in the Western Siberia. This field is characterized by low permeability and complex reservoir structure. Currently various types of well patterns are used for the development of reservoirs with low effective matrix permeability. These types of well patterns contain the horizontal wells with multiple hydraulic fractures. There is wherein a dependence of the used type of well pattern on permeability, the structure and sedimentation conditions of the reservoir.

The article presents an overview of the implementation of various development systems based on multi-stage hydraulic fracturing, which are used to improve the efficiency of reserves development in the low-permeability areas of the AC10-12 resevoir of the Priobskoye field. The current results of the implementation are given for the following types of the well pattern: 1) basic; 2) infill; 3) multilayer; 4) transverse (horizontal wells are drilled perpendicular the direction to the regional stress); 5) improved well row spacing; 6) waterflooding using injection horizontal wells. The comparison of wells liquid production decline rate, wells total oil production between the considered type of the well pattern and the basic type of the well pattern was made (during a first year). It is shown that the development with the use of various types of well patterns is more effective for ultra-low permeability reservoirs in case of the Priobskoye field than with the use only the basic type of the well pattern.

References

1. Kaunov A.S., Khayrullin A.A., Overview of the experience of using multi-stage hydraulic fracturing technology in Russia and abroad (In Russ.), Akademicheskiy zhurnal Zapadnoy Sibiri, 2016, V. 12, no. 5(66), pp. 19-22.

2. Ryazantsev M.V., Mironenko A.A., Kuzin I.G. et al., Priobskoye oil field - 40 years for the Motherland weal! (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 6, pp. 20-25, DOI: https://doi.org/10.24887/0028-2448-2022-6-20-25

3. Ziatdinova E.Yu., Egorov E.L., Osorgin P.A. et al., The main stages of evolution of the hydraulic fracturing technology at the Priobskoye field of RN-Yuganskneftegas LLC (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 5, pp. 75-79, DOI: https://doi.org/10.24887/0028-2448-2022-5-75-79

4. Miroshnichenko A.V., Sergeychev A.V., Korotovskikh V.A. et al., Innovative technologies for the low-permeability reservoirs development in Rosneft Oil Company (In Russ.), (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 11, pp. 105-19, DOI: https://doi.org/10.24887/0028-2448-2018-12-05-109

5. Sergeychev A.V., Toropov K.V., Antonov M.S. et al., Automated intelligent assistant in the selection of well placement when developing hard-to-recover reserves (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 10, pp. 76-81, DOI: https://doi.org/10.24887/0028-2448-2020-10-76-81

6. Fakhretdinov I.V., Integrated monitoring of horizontal wells with multistage hydraulic fracturing at the implementation stage within the priobskiy oil field for their work effectiveness (In Russ.), Problemy sbora, podgotovki i transporta nefti i nefteproduktov, 2017, no. 4, pp. 92–99.

7. Miroshnichenko A.V., Korotovskikh V.A., Musabirov T.R. et al., Investigation of horizontal wells with multi-stage hydraulic fracturing technological efficiency in the development of low-permeability oil reservoirs (In Russ.), SPE-206412-RU, 2021, DOI: https://doi.org/10.2118/206412-MSSPE-206412-RU

8. Shabalin M., Khabibullin G., Suleymanov E. et al., Tight oil development in RN-Yuganskneftegas (In Russ.), SPE-196753-MS, 2019, DOI: https://doi.org/10.2118/196753-MS

9. Hustak C., Dieva R., Baker R. et al., Waterflooding a multi-layered tight oil reservoir developed with hydraulically fractured horizontal wells, SPE-185021-MS, 2017, DOI: https://doi.org/10.2118/185021-MS

The work is devoted to the analysis of the reasons for the decrease in the intake capacity of horizontal injection wells at the Vostochno-Messoyakhskoye oil and gas condensate field, as well as the development of measures to restore it. A complex of experimental studies has been carried out, including the study of mineralogy, granulometry and component composition of sediments; analysis of the possibility of salt deposition of poorly soluble salts; formation of persistent oil-water emulsions; investigation of the solubility of sediments in acid composition and the development of a formulation with low corrosion aggressiveness and increased solvent capacity for sediments. The presence of calcium carbonate, iron compounds and quartz sand in sediments from filter of modular water injection station, as well as in the bottom-hole zone of the injection well formation, has been established. The reasons for the appearance of calcium carbonate in the deposits are the presence of elevated concentrations of calcium and bicarbonate ions in the raw water of the central pumping station, heating of the raw water on the modular water injection station by CCP pumps, insufficient dosage of the salt deposition inhibitor used to protect against calcium carbonate precipitation. Filtration tests were carried out on the rock of the PK1-3 formation and the selection of compositions capable of increasing the permeability of the formation rock. Compositions for acid bath and injection into the reservoir to restore intake capacity have been developed, and their pilot testing has been carried out. Acid compositions have been developed that effectively dissolve deposits from the modular water injection station and bottom-hole formation zone of horizontal injection wells of the Vostochno-Messoyakhskoye field. A complex technology of hydrochloric acid treatments of the bottom-hole formation zone with the establishment of an acid bath and the injection of an acid composition into the reservoir with a pre-treatment of a mutual solvent is proposed. Field testing of selected compositions for processing of the bottom-hole zone of injection wells was carried out, as a result of which an increase in the well intake capacity coefficient was achieved by 2.05 – 2.61 times.

References

1. Tronov V.P., Promyslovaya podgotovka nefti (Field oil treatment), Kazan’: Fen Publ., 2000, 416 p.

2. Lutoshkin G.S., Sbor i podgotovka nefti, gaza i vody k transportu (Collection and processing of oil, gas and water), Moscow: Nedra Publ., 1977, 192 p.

3. Glushchenko V.N., Ptashko O.A., Kharisov R.Ya., Denisova A.V., Kislotnye obrabotki. Sostavy, mekhanizmy reaktsii. Dizayn (Acid treatments. Compositions, reaction mechanisms. Design), Ufa: Gilem Publ., 2010, 392 p.

4. Dolomatov M.Yu., Telin A.G., Ezhov M.B. et al., Fiziko-khimicheskie osnovy napravlennogo podbora rastvoriteley asfal’tosmolistykh veshchestv (Physical and chemical bases of directed selection of solvents for asphalt-resinous substances), Moscow: Publ. of TsNIITEneftekhim, 1991, 47 p.

The article discusses results of core flooding studies to determine optimal filtration modes of acid compositions in cores from different producing fields, as well as comparison of mathematical models matched with the laboratory studies results to be applied in the software engineering tools for carbonate acidizing design. Various approaches to the mathematical description of wormholes formation in core samples have been considered and, finally, it was decided upon semiempirical models as best-suited for complex engineering tool for carbonate acidizing design. For model matching, a series of core flooding experiments were performed. Different initial concentrations of hydrochloric acid, and different additives to control reaction rate were used. A good match between the models and the forecast data was obtained. To extrapolate these models to field conditions, two universal models based on two different approaches, a simplified pseudostationary single-phase isothermal model and a non-stationary multi-phase non-isothermal model, were developed, which were integrated with the semiempirical models. It was found that the non-stationary multi-phase non-isothermal model has a greater potential for forecast of matrix acidizing performance, however the simplified pseudostationary single-phase model can be useful as a proxy-model to perform quick calculations. The results demonstrate that the models can be successfully realized in the acidizing design software tools. The developed models were the basis of the software package for modeling and design of carbonate acidizing in fields operated by PJSC TATNEFT.

References

1. Williams B.B., Gidley J.L., Schechter R.S., Acidizing fundamentals, New York: SPE Monograph Series, 1979, 124 p.

2. Kalfayan L.J., Martin A.N., The art and practice of acid placement and diversion: History, present state and future, SPE-124141-MS, 2009, DOI: https://doi.org/10.2118/124141-MS

3. Hoefner M.L., Fogler H.S., Pore evolution and channel formation during flow and reaction in porous media, AIChE Journal, 1988, V. 34, No. l, pp. 45–54, DOI: https://doi.org/10.1002/aic.690340107

4. Fredd S.N., Fogler H.S., Optimum conditions for wormhole formation in carbonate porous media: Influence of transport and reaction, SPE-56995-PA, 1999, DOI: https://doi.org/10.2118/56995-PA

5. Gong M., El-Rabaa A.M., Quantitative model of wormholing process in carbonate acidizing, SPE-52165-MS, 1999, DOI: https://doi.org/10.2118/52165-MS

6. Schwalbert M.P., Ding Zhu, Hill A.D., Anisotropic-wormhole-network generation in carbonate acidizing and wormhole-model analysis through averaged-continuum simulations, SPE-185788-PA, 2018, DOI: https://doi.org/10.2118/185788-PA

7. Buijse M., Glasbergen G.A., Semiempirical model to calculate wormhole growth in carbonate acidizing, SPE-96892-MS, 2005, DOI: https://doi.org/10.2118/96892-MS

8. Furui K., Burton R.C., Burkhead D.W. et al., A comprehensive model of high-rate matrix acid stimulation for long horizontal wells, SPE-134265-MS, 2010, DOI: https://doi.org/10.2118/134265-MS

9. Zhuchkov S.Yu., Review of methods applied for modeling of a carbonate formation acidizing (In Russ.), Neftepromyslovoe delo, 2013, no. 2, pp. 29–33.

10. Bulgakova G.T., Sharifullin A.R., Kharisov R.Ya. et al., Laboratory and theoretical researches of matrix acid-based carbonates processing (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2010, no. 5, pp. 75–79.

11. Bulgakova G.T., Kharisov R.Ya., Sharifullin A.R., Pestrikov A.V., Optimizing the design of matrix treatments, SPE-143959-MS, 2011, DOI: https://doi.org/10.2118/143959-MS.

12. Kanevskaya R.D., Vol'nov I.A., Acidizing simulation of carbonate reservoir (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2009, no. 7, pp. 97–99.

13. Cheng H., Schwalbert M.P., Hill A.D., Zhu D., A fundamental model for wormhole formation including multiphase flow, IPTC-19121-MS, 2019, DOI: https://doi.org/10.2523/IPTC-19121-MS

14. Kharisov R.Ya., Folomeev A.E., Bulgakova G.T., Telin A.G., The complex approach to the choice of the optimum acid composition for well stimulation in carbonate (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2011, no. 2, pp. 78–82.

The peculiarity of the initial opening of productive intervals makes it necessary to clean the bottomhole formation zone of the well before conducting hydrodynamic studies. The article presents the results of an extensive set of works on the selection of the optimal technology for acid treatment of an exploratory well in a high-temperature carbonate reservoir, confined to the Timan-Pechora oil and gas province. The paper presents the main geological and physical characteristics of the object under study, which also reduce the effectiveness of the acid treatment. The selection of an acid composition for conducting a well treatment was made taking into account the experience of working at an analogous field. The results of physicochemical studies to identify the risks of the negative impact of the acid composition on the rock, the study of the kinetics of the interaction of the acid composition with the rock and the physical modeling of acidizing are presented. A semi-empirical mathematical model of acid dissolution based on Damköller and Pecklet numbers and acid capacity was chosen to determine optimal treatment parameters (injection rate, acid volume) and develop recommendations for treatments. The treatment was performed using a high-tech tubing test assembly to combine all process operations in a single tripping operation, minimize time gaps between operations, eliminate the well killing stage after treatment, and eliminate risks associated with pulling the assembly out of the well after perforation of the pay interval. According to test results, the proposed solution showed its technological efficiency. The prospects for further development of this technology are outlined in relation to the geological and physical features of this reservoir.

References

1. Prishchepa O.M., Nefedov Yu.V., Ayrapetyan M.G., Hydrocarbon potential of the Arctic shelf sector of the north Timan-Pechora petroleum province on the results of regional researches (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2020, V. 15, no. 1, DOI: https://doi.org/10.17353/2070-5379/4_2020

2. Zakharova O.A., Zagranovskaya D.E., Vilesov A.P. et al., The Pechora Sea shelf – clusters of hydrocarbon potential of Timan-Pechora province (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 1, pp. 12–17, DOI: https://doi.org/10.24887/0028-2448-2021-1-12-17

3 Folomeev A.E., Sovershenstvovanie tekhnologii kislotnogo vozdeystviya na vysokotemperaturnye karbonatnye kollektory (Improving the technology of acid treatment of high-temperature carbonate reservoirs): thesis of candidate of technical science, Ufa, 2020.

4. Shaydullin V.A., Folomeev A.E., Vakhrushev S.A. et al., Field study of a new radial drilling technology followed by acidizing (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 7, pp. 108–114, DOI: https://doi.org/10.24887/0028-2448-2022-7-108-114

5. Folomeev A.E., Sharifullin A.R., Vakhrushev S.A. et al., Theory and practice of acidizing high temperature carbonate reservoirs of R. Trebs oil field, Timan-Pechora Basin, SPE-171242-MS, 2014, DOI: http://dx.doi.org/10.2118/171242-MS

6. Telin A.G., Ismagilov T.A., Akhmetov N.Z. et al., An integrated approach to increasing the efficiency of acid well treatments in carbonate reservoirs (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2001, no. 8, pp. 69–74.

7. Trushin Y., Aleshchenko A., Danilin K. et al., Complex approach to the design of acid treatment of carbonate reservoirs, SPE-196977-MS, 2019, DOI: https://doi.org/10.2118/196977-MS

8. Gong M., El-Rabaa A.M. Quantitative model of wormholing process in carbonate acidizing, SPE-52165-MS, 999, DOI: https://doi.org/10.2118/52165-MS

9. Vakhrushev S.A., Folomeev A.E., Kotenev Yu.A., Nabiullin R.M., Acid treatment with diverting on carbonate reservoirs of R. Trebs oil field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 4, pp. 112–117.

Development of Vietsovpetro fields is characterized by decreasing oil production and increasing water cut. The increase of stream water cut reduces the productive capability of gas lift and increases the bottomhole pressure. Appearance of leaks in the downhole equipment complicates the situation and leads to the enhanced consumption of the compressed gas. Gas lift efficiency depends on many factors: layout, actuating pressure and size of gaslift valves, compressed gas consumption rate, downhole equipment leak integrity, etc. During the operation, equipment wearing increases and leak integrity fails, leading to gaslift gas leaks and efficiency reduction down to the fill stop of the equipment. Restoration of well performance requires the workover operations with replacement of the downhole equipment which is a cost demanding activity under the offshore conditions. Alternative to the downhole equipment replacement may be found in deploying the special inserted isolating assemblies to eliminate the leaks. To perform the pilot tests on eliminating the leaks in the downhole equipment, Vietsovpetro has chosen the technology of Tubing Pack-off due to the following factors: applicability in the existing geophysical conditions, simplicity and safety of implementation, equipment and services costs. Tubing Pack-off assemblies represent the module units, ran to the target depth and installed in the designated interval by wireline techniques. These assemblies consist of separately adjustable elements which ensure the leak integrity of the isolated interval with the possibility to install a small-sized mandrel with gaslift valve to deepen the compressed gas injection point. Application of Tubing Pack-off allows increasing the well current production rates by eliminating the leaks of the downhole equipment, multiply reduce the workover costs, improve the gas lift operation efficiency and optimise the operational costs by lowering the compressed gas injection volume. The article includes the defined application criteria of Tubing Pack-off system for Vietsovpetro wells and specified perspectives for improving Vietsovpetro gaslift wells diagnostics technology.

References

1. Julian J.Y., Jackson J.C., White T.M., A history of gas lift valve and gas lift mandrel damage and subsequent retrofit gas lift straddle installation in Alaska, SPE-168304-MS, 2014, DOI: https://doi.org/10.2118/168304-MS

2. Lashari N., Develop optimum gas lift methods to improve gas lift efficiency using gas lift pack-off, deep gas lift, and deep lift set, International Journal of Advanced Research in Engineering and Technology (IJARET), 2020, V. 11, no. 11, pp. 1096-1114, DOI: https://doi.org/10.34218/IJARET.11.11.2020.100

The modern assessment of the economic efficiency of an oil and gas project involves the construction of a specific economic and mathematical calculation model, as well as the analysis of project criteria based on a set of predictive technological indicators for the reservoirs being developed and the field as a whole. The complexity of such modeling lies in the initial collection of information and its constant updating, since each field is individual and has its own geological and technological features of development, various options and standards for capital and operating costs, as well as tax models. Taking into account the latter provision, the intellectual-logical system (ILS) GRAF was developed. The core of the system is the use of a network (graph) form of representation of computational models, as well as a database management system of initial technical and economic indicators for various options for the development of oil and gas fields. The calculation structure is hierarchical and may change depending on the degree of knowledge and exploration of deposits, as well as on the possible change in the volume and content of the initial geological, technological and economic information. The result of an economic assessment based on the use of knowledge bases and data is to identify the most rational option for developing a field that meets the criterion for achieving the maximum economic effect from the possible complete extraction of oil reserves from the reservoirs while observing the requirements of ecology, subsoil and environmental protection. It is relevant that the creation of models of knowledge bases and databases for the economic assessment of the development of oil and gas fields allow storing information on fields in a systematic way and reproducing the history of economic indicators of field development in dynamics for the operation of an applied ILS in order to select the most effective options for the development of various deposits.

References

1. Pospelov G.S., Iskusstvennyy intellekt – osnova novoy informatsionnoy tekhnologii (Artificial intelligence is the basis of new information technology), Moscow: Nauka Publ., 1988, 280 p.

2. Vagin V.N., Deduktsiya i obobshchenie v sistemakh prinyatiya resheniy (Deduction and generalization in decision-making systems), Moscow: Nauka Publ., 1988, 384 p.

3. Pospelov D.A., Prikladnye sistemy iskusstvennogo intellekta (Applied systems of artificial intelligence), Kishinev: Shtiintsa Publ., 1993, 300 p.

4. Gavrilova T.A., Khoroshevskiy V.F., Bazy znaniy intellektual'nykh sistem (Knowledge bases of intelligent systems), St. Peterburg: Piter Publ., 2000, 200 p.

5. Bogatkina Yu.G., Otsenka effektivnosti investitsionnykh proektov v neftegazovoy otrasli s ispol'zovaniem mekhanizmov avtomatizirovannogo modelirovaniya (Evaluation of the effectiveness of investment projects in the oil and gas industry using automated modeling mechanisms), Moscow: Maks Press Publ., 2020, 248 p.

6. Zheltov Yu.P., Zolotukhin A.B., Ponomareva I.A., Metody prognozi-rovaniya razvitiya neftegazovogo kompleksa (Methods for forecasting the development of the oil and gas complex), Moscow: Nauka Publ., 1991, 230 p.

7. Rodionova L.N., Karamutdionova D.M., Peculiarities of investment projects efficiency evaluation in oil industry (In Russ.), Ekonomika i upravlenie narodnym khozyaystvom, 2015, no. 9(130), pp. 50–54.

8. Abakumov G.V., Evaluation of the economic efficiency of oil and gas production projects in Western Siberia (In Russ.), Neftegaz.ru, 2009, no. 8.

9. Ponomareva. I.A, Bogatkina Yu.G., Improving the regulatory and tax system to improve the efficiency of oil field development (In Russ.), Problemy ekonomiki i upravleniya neftegazovym kompleksom, 2014, no. 1, pp. 6–9.

10. Federal Law No. 39-FZ of February 25, 1999 (as amended on July 3, 2016) “Ob investitsionnoy deyatel'nosti v Rossiyskoy Federatsii, osushchestvlyaemoy v forme kapital'nykh vlozheniy” (On investment activities in the Russian Federation carried out in the form of capital investments), URL: http://www.consultant.ru

11. URL: http://www.rosneft.ru

12. Isachenko V.M., Otsenka proektnoy kapitaloemkosti razrabotki neftyanykh mestorozhdeniy (Assessment of project capital intensity of oil field development): thesis of candidate of economic sciences, Tyumen, 2004.

13. Raschet kapital'nykh zatrat (vlozheniy) v razrabotku mestorozhdeniya (Calculation of capital costs (investments) in field development), URL: https://kazedu.com/referat/197598/1

Competition in the oil and gas industry is growing in the world, and it obliges oil companies to constantly improve the efficiency of their business processes. One of the tools that allows Zarubezhneft JSC to achieve this is system reengineering and automation of the data handling business process. To solve this problem, in 2020 Zarubezhneft JSC initiated a digital project to create a corporate digital data management platform NESTRO DATA as part of its digital transformation program. The article presents the results of a project to create a corporate digital platform for data management NESTRO DATA as a centralized source of the "Single version of the truth" for all major aspects of the Company activities to improve the efficiency of analytical work with data and management decision-making. During the implementation of the project, individual unique specialized production systems used in the regions of the Company presence around the world are integrated into a single information space. Within the framework of the project, in addition to directly creating the NESTRO DATA digital platform, important organizational and methodological tasks were completed to ensure the systematic operation of the new tool in the company: a Data Management Competence Center was created, a Data Management Strategy was approved, processes were regulated in one of the key areas for further transfer of the platform into the process, management of centralized management of regulatory and reference information, management of data integration and interoperability in the Zarubezhneft Group of Companies.

The factors complicating oil well operation negatively affect oil production and have always forced oil engineers to analyze, search and foresee measures for their elimination, keeping in mind the maximum technical and economic efficiency. The study dwells upon the creation of technologies applicability matrix for the protection of deep-well pumping equipment from complicating factors in Rosneft Oil Company based on Mechfond information system (IS). Matrix of well stock protection technologies contain a database (or ‘knowledge base’) of technological solutions aimed at maximizing the guaranteed and effective protection of the producing well stock from the negative impact of various complicating factors. As a result the model allows to quickly analyze and select among all known deep-well pumping equipment technical solutions (protection technologies) based on formed criteria, using the accumulated experience (geological and technical conditions for certain protection technology). The uniqueness of the matrix knowledge base lies in systematization of Rosneft long-term technological and scientific experience (including Subs, R&D and expert centers of the Company) obtained during the pilot testing and scaling on the industrial level of technological solutions, aimed at protecting the producing well stock from the negative impact of complicating factors. The article describes matrix composition and structure, stages of creation and usage examples with the application of Mechfond IS.

References

1. Kudryashov S.I., Salt management at Rosneft fields (In Russ.), Neftegazovoe delo, 2006, no. 2, pp. 25.

2. Malyshev A.S., Khabibullin R.A., Ganiev I.M. et al., Development of the templates of applicability of technologies to prevent scaling in producing wells (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2009, no. 11, pp. 48–50.

3. Lunin D.A., Minchenko D.A., Noskov A.B. et al., System to improve operational quality of artificial lift wells of Rosneft Oil Company in response to negative impact of complicating factors (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 4, pp. 86–91, DOI: 10.24887/0028-2448-2021-4-86-91

4. Kosilov, D.A. Mironov, D.V. Naumov I.V., Mekhfond corporate system: achieved results, medium-term and long-term perspectives (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 11, pp. 70–73, DOI: 10.24887/0028-2448-2018-11-70-73

5. Certificate of official registration of a computer program no. 2019617213. Programma informatsionnoy sistemy upravleniya mekhanizirovannym fondom skvazhin (The program of the information system for the management of mechanized well stock), Authors: Akhtyamov A.R., Volkov M.G., Noskov A.B.

Operational monitoring of the well stock is a time-consuming task in base oil production. Among such tasks are the following: on-time detection of deviations in the flow rate of produced products, determination of the exact causes of changes in field parameters, as well as analysis of large data sets. This is especially true for oil and gas companies in case of large well stock and and high degree of reserves development. The development of digital technologies creates conditions for the integration of intelligent systems into the process of oil and gas production. Automatic processing of huge arrays of field data allows quickly monitoring the state of the base stock of wells for localization of the most problematic areas.

The article presents the developed new concept for working with oil flow rate deviations based on automated algorithms and mathematical approaches. The main objectives of the presented work are the development of a systematic approach to online monitoring field parameters, increasing accuracy and speed in determining deviations in oil production, as well as minimizing routine manual labor and reducing the impact of human factors. Due to the automated approach, the costs of developing the fund are significantly reduced, labor costs are reduced and the degree of influence of errors related to the human factor is reduced, in addition, daily monitoring helps to react in time to changes in the oil flow rate, and increasing the accuracy of explaining the causes of deviations significantly improves the quality of the selection of measures to eliminate them. According to methodology, software was implemented - a system of digital tools for identifying and explaining the causes of deviations in oil production, and factor analysis for the selected period. The developed approaches have been introduced into the process of the production company. This made it possible to increase the effectiveness of monitoring well stock.

References

1. Andrianova A.M., Yudin E.V., Ganeev T.A. et al., Application of intelligent methods for analysis high-frequency production data for solving oil engineering challenges (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 9, pp. 70–75, DOI: https://doi.org/10.24887/0028-2448-2021-9-70-75

2. Asmandiyarov R.N., Kladov A.E., Lubnin A.A. et al., Automatic approach to field data analysis (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2011, no. 6, pp. 58–61.

3. Boschetti A., Massaron L., Python data science essentials, Packt Publishing Ltd., 2015, 472 p.

4. Mining J., Python machine learning: Everything you should know about Python Machine Learning including Scikit Learn, Numpy, PyTorch, Keras and Tensorflow with step-by-step examples, practical exercises, International Kindle Paperwhite, 2019, 124 p.

5. Pylov P.A., Ivina O.A., Fundamental'nye tipy kross-validatsii dlya otsenki kachestva modeley mashinnogo i glubokogo obucheniya (Fundamental types of cross-validation for evaluating the quality of machine learning and deep learning models), Proceedings of XIII All-Russian Scientific and Practical Conference of Young Scientists “ROSSIYa MOLODAYa” (RUSSIA YOUNG), 20-23 April 2021, URL: https://science.kuzstu.ru/wp-content/Events/Conference/RM/2021/RM21/pages/Articles/031520.pdf

The article provides brief information on the design features of concreted pipes used in recent years in the construction of offshore pipelines, as well as in the overhaul of main pipelines operated in difficult engineering and geological conditions. The problem is setting of the stress-strain state of an underwater section of an offshore oil pipeline consisting of a blurred bare part and jointly deforming with it adjacent underground parts in which the soil was not subjected to flooding. The following statements of the problem of the stress-strain state of the calculated section of the oil pipeline are considered: 1) taking into account the effect of internal pressure and temperature stresses on the bending of the pipeline, causing additional bending of the gas pipeline; 2) neglecting the effect of internal pressure and temperature stresses on the bending of the concreted pipe. A method for joint numerical integration of differential equations describing the stress-strain state of a blurred exposed part and adjacent underground parts has been developed. Computer calculation programs have been compiled, in which constant integrations have been found, plots of the main characteristics of the stress-strain state along the entire length of the considered section of the oil pipeline have been constructed. Calculations of the main characteristics of the stress-strain state are carried out, diagrams of pipeline deflection and bending stresses are constructed. The tables show the extreme values of deflection and bending stresses from span and support bending moments for various values of operating parameters and soil conditions on adjacent underground parts. The influence on the ascent of the concreted pipe of the length of the blurred bare part, the parameters of operation, the weakening of the rigidity of soils due to their liquefaction in the underground part was revealed. Recommendations are given to identify possible causes of its ascent, as well as a description of the method of returning the pipeline to its design position.

References

1. Aynbinder A.B., Kamershteyn A.G., Raschet magistral'nykh truboprovodov na prochnost' i ustoychivost' (Calculation of trunk pipelines for strength and stability), Moscow: Nedra Publ., 1982, 340 p.

2. Bykov L.I., Mustafin F.M., Rafikov S.K. et al., Tipovye raschety pri sooruzhenii i remonte gazonefteprovodov (Typical calculations for the construction and repair of gas and oil pipelines), St.Petersburg: Nedra Publ., 2011, 748 p.

3. Vasil'ev G.G., Goryainov Yu.A., Saksaganskiy A.I., Advantages and disadvantages of modern approaches to ballasting underwater crossings (In Russ.), Neft' i gaz Sibiri, 2012, no. 1, pp. 30–37.

4. Dimov L.A., Bogushevskaya E.M., Magistral'nye truboprovody v usloviyakh bolot i obvodnennoy mestnosti (Main pipelines in swamps and flooded areas), Moscow: Publ. of Moscow Mining State University, 2010, 392 p.

5. Korobkov G.E., Zaripov R.M., Shammazov I.A., Chislennoe modelirovanie napryazhenno-deformirovannogo sostoyaniya i ustoychivosti truboprovodov i rezervuarov v oslozhnennykh usloviyakh ekspluatatsii (Numerical modeling of stress-strain state and stability of pipelines and reservoirs in complicated operating conditions), St. Petersburg, Nedra Publ., 2009, 409 p.

6. Shammazov A.M., Zaripov R.M., Chichelov V.A., Korobkov G.E., Raschet i obespechenie prochnosti truboprovodov v slozhnykh inzhenerno-geologicheskikh usloviyakh. Chislennoe modelirovanie napryazhenno-deformirovannogo sostoyaniya i ustoychivosti truboprovodov (Calculation and maintenance of strength of pipelines in complicated geotechnical conditions. Numerical modeling of stress-strain state and stability of pipelines), Part 1, Moscow: Inter Publ., 2005, 706 p.

7. Il'gamov M.A., Model' vsplytiya podvodnogo truboprovoda. Fizika. Tekhnicheskie nauki (In Russ.), Doklady Rossiyskoy akademii nauk. Fizika, tekhnicheskie nauki, 2022, V. 504, no. 1, pp. 10–14, DOI:10.31857/S2686740021010053.

8. Il'gamov M.A., Kolebaniya uprugikh obolochek, soderzhashchikh zhidkost' i gaz (Vibrations of elastic shells containing liquid and gas), Moscow: Nauka Publ., 1969, 181 p.

9. Bolotin V.V., Novichkov Yu.N., Mekhanika mnogosloynykh konstruktsiy (Mechanics of sandwich structures), Moscow: Mashinostroenie. 1980. – 376 s.

10. Lapteva T.I., The strength and stability of offshore pipelines in the presence of subaqueous permfrost on land landfall (In Russ.), Ekspozitsiya. Neft'. Gaz, 2016, no. 7(53), pp. 76–79.

11. Mansurov M.N., Lapteva T.I., Kim S.D. et al., Influence of soft soils on the stability of offshore pipelines (In Russ.), Oil&Gaz Rossiya, 2011, no. 8, pp. 60–63.

12. Shammazov A.M., Zaripov R.M., Chichelov V.A., Korobkov G.E., Raschet i obespechenie prochnosti truboprovodov v slozhnykh inzhenerno-geologicheskikh usloviyakh. Chislennoe modelirovanie napryazhenno-deformirovannogo sostoyaniya i ustoychivosti truboprovodov (Calculation and maintenance of strength of pipelines in complicated geotechnical conditions. Numerical modeling of stress-strain state and stability of pipelines), Part 2, Moscow: Inter Publ., 2006, 564 p.

IIn the last three decades, polymer-based anti-turbulent additives have been widely used in the Russian Federation in order to reduce hydrodynamic resistance when pumping oil and oil products through main pipelines and thus to reduce energy costs. The hydrodynamic properties of presently available commercial additives of Russian and foreign manufacture were experimentally studied in a laboratory environment and then a comparison was made of their anti-turbulent properties. Anti-turbulent properties of additives were tested in two hydrocarbon solvents (gasoline and oil) using a turbulent rheometer. It was determined that the transition from one solvent to another is accompanied by a change in the efficiency of additives depending on the physicochemical nature of the solvents and their rheological properties. It has been found out that the optimal concentration, at which the maximum effect of hydrodynamic drag reduction was achieved, was one and a half times higher in oil than in gasoline. The obtained pattern was a consequence of the presence of heavy components (resins, asphaltenes, and high molecular weight paraffins) in oil. High molecular weight polymers were partially adsorbed on these components and, therefore, the content of the hydrodynamically active component in solution decreased. Thus, the optimal concentrations of the polymer in oil are higher than in gasoline, hence more polymer is required the pipeline transportation of oil requires more polymer than the pumping of light oil products. It has been found out that oil-soluble additives from Russian manufacturers are not inferior in their performance to imported analogues. All additives are based on natural hydrocarbons, so they are fully compatible with oil and do not adversely affect the pipeline network and subsequent oil refining.

References

1. Bakhtizin R.N., Gareev M.M., Lisin Yu.V. et al., Nanotekhnologii dlya snizheniya gidravlicheskogo soprotivleniya truboprovodov (Nanotechnologies to reduce the hydraulic resistance of pipelines), St. Petersburg: Nedra Publ., 2018, 352 p.

2. Burger E.D., Munk W.R., Wahl H.A., Flow increase in the Trans Alaska Pipeline through use of a polymeric drag reducing additive, Journal of Petroleum Technology, 1982, V. 34, no. 2, pp. 377–386, DOI: https://doi.org/10.2118/9419-PA

3. Mut Ch., Monakhen M., Peseto L., The use of special additives to reduce the cost of operating pipelines (In Russ.), Neft, gaz i neftekhimiya za rubezhom, 1986, no. 7, pp. 60–62.

4. Gareev M.M., Nesyn G.V., Manzhay V.N., The results of addition to the oil flow for reduce the hydraulic resistance (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1992, no. 10, pp. 30–31.

5. Nesyn G.V., Manzhay V.N., Popov E.A. et al., Experiment to reduce hydrodynamic resistance on the main pipeline Tikhoretsk-Novorossiysk (In Russ.), Truboprovodnyy transport, 1993, no. 4, pp. 28–30.

6. Nesyn G.V., Sunagatullin R.Z., Shibaev V.P., Malkin A.Y., Drag reduction in transportation of hydrocarbon liquids: From fundamentals to engineering applications, Journal of Petroleum Science and Engineering, 2018, V. 161, pp. 715–725, DOI: https://doi.org/10.1016/j.petrol.2017.10.092

7. Абдусалямов А.В., Манжай В.Н., Antiturbulent suspension additives for a pipeline transportation of oil (In Russ.), Известия вузов. Нефть и газ, 2013, no. 4, pp. 102–106.

8. Konovalov K.B., Abdusalyamov A.V., Manzhay V.N. et al., Comparative study of the effect of antiturbulent additives for hydrocarbon liquids (In Russ.), Kratkie soobshcheniya po fizike FIAN = Bulletin of the Lebedev Physics Institute, 2015, no. 12, pp. 36–42.

9. Manzhai V.N., Echevskaya L.G., Ilyushnikov A.V. et al., Antiturbulent powers of higher polyolefins and olefin terpolymers (In Russ.), Журнал прикладной химии = Russian Journal of Applied Chemistry, 2004,V. 77, no. 3, pp. 456–460.

10. Tavtorkin A.N., Gavrilenko I.F., Kostitsyna N.N. et al., Comparison of the turbulent drag reduction effectiveness of polymers from higher olefin monomers (hexene, octene, decene, dodecene) in the production of hydrodynamic drag reducing agents for transportation of hydrocarbon liquids (In Russ.), Журнал прикладной химии = Russian Journal of Applied Chemistry, 2020, V. 93, no. 6, pp. 788–793, DOI: 10.31857/S004446182006002X

11. Gareev M.M., Lisin Yu.V., Manzhay V.N., Shammazov A.M., Protivoturbulentnye prisadki dlya snizheniya gidravlicheskogo soprotivleniya truboprovodov (Antiturbulent additives to reduce the hydraulic resistance of pipelines), St. Petersburg: Nedra Publ., 2013, 228 p.

12. Manzhai V.N., Nasibulina Yu.R., Kuchevskaya A.S., Filimoshkin A.G., Physico-chemical concept of drag reduction nature in dilute polymer solutions (the Toms effect), Chemical Engineering and Processing: Process Intensification, 2014, V. 80, pp. 38–42, DOI:10.1016/j.cep.2014.04.003

13. Manzhay V.N., Nosikova Yu.R., Abdusalyamov A.V., Degradation of polymer solutions in a turbulent flow in a cylindrical channel (In Russ.), Журнал прикладной химии = Russian Journal of Applied Chemistry, 2015, V. 88, no. 1, pp. 125–131.

14. Manzhay V.N., Effect of anti-turbulent additives on the flow of hydrocarbon fluids at low temperatures (In Russ.), Нефтяное хозяйство = Oil Industry, 2018, no. 3, pp. 92–96, DOI: 10.24887/0028-2448-2018-3-92-96

15. Virk P.S., Drag reduction fundamentals, AIChE Journal, 1975, V. 21, no. 4, pp. 625–246, DOI: https://doi.org/10.1002/aic.690210402

Various mechanical and structural characteristics of individual sections of the welded joint, formed under the influence of the thermodeformation cycle of fusion welding, have different fracture resistance. The difference in the mechanical characteristics of the welded joint zones is due to structural changes at the micro and macro levels. Changes at the micro level due influenced by the temperature gradient have a hierarchical relationship with changes at the macro level. A large number of studies have been devoted to these issues, including for welded joints made of ferrite-pearlite steels. However, the assessment of the cyclic durability of a pipe welded assembly with technological or operational stress concentrators located in various zones of the welded joint is still an urgent task. In addition, the effect of cyclic loads on the structure and resistance of individual sections of welded joints, as well as on the interaction of adjacent sections of zones of mechanical heterogeneity of welded joints requires additional study. The mutual influence of neighboring zones of mechanical heterogeneity of welded joints leads to localization and development of plastic deformations in the loading cycle. The local zone of plastic deformation is a concentrator, which in the presence of a technological defect of the welded joint has an additional effect on the stress-strain state and on the transition in the concentration zone to the active formation and growth of secondary cracks. Identification of the most dangerous zones of mechanical heterogeneity of welded joints under cyclic loading conditions will improve the assessment of the danger of defects of welded joints detected during diagnostic work. Taking into account the influence of zones of mechanical heterogeneity will make it possible to more accurately predict the places of crack formation.

References

1. Fedoseeva E.M., Mechanical and structural microinhomogeneity of welded compounds of X65 steel (In Russ.), Vestnik Permskogo nauchno-issledovatel’skogo politekhnicheskogo universiteta. Mashinostroenie, materialovedenie = Bulletin PNRPU. Mechanical engineering, materials science, 2016, no. 2, pp. 76-88.

2. Berg V.I., Chekardovskiy M.N., Yakubovskaya S.V., Toporov V.S., Influence of heterogeneity of mechanical properties of various zones of the welded butt joints work connections in elastic-plastic deformation stage (In Russ.), Sovremennye problemy nauki i obrazovaniya, 2015, no. 2-3, URL: htps://science-education.ru/ru/article/view?id=23518

3. Yamilev M.Z., Tigulev E.A., Yushin A.A. et al., Evaluating mechanical heterogeneity of pipelines welded joints (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 11, pp. 128–131, DOI: https://doi.org/10.24887/0028-2448-2020-11-128-131

4. Raspopov A.A., Yamilev M.Z., Tigulev E.A., Vliyanie mekhanicheskikh svoystv neodnorodnykh svarnykh soedineniy na ikh nesushchuyu sposobnost’ (Influence of mechanical properties of inhomogeneous welded joints on their bearing capacity), Proceedings of International Conference “Perspektivnye materialy s ierarkhicheskoy strukturoy dlya novykh tekhnologiy i nadezhnykh konstruktsiy” (Promising materials with a hierarchical structure for new technologies and reliable designs), Kh International Conference “Khimiya nefti i gaza” (Chemistry of oil and gas), Tomsk: Publ. of TSU, 2018, pp. 537-538.

5. Shakhmatov D.M., Shakhmatov M.V., Evaluation of the strength of mechanically inhomogeneous welded joints (In Russ.), Svarka i diagnostika, 2018, no. 1, pp. 32-36.

6. Dil’man V.L., Ostsemin A.A., Influence of surface defects on the static strength of welds in spiral pipes (In Russ.), Khimicheskoe i neftegazovoe mashinostroenie, 2004, no. 2, pp. 16-19.

7. Erofeev V.V., Raspopov A.A., Golikov V.N., Calculation of the bearing capacity of welded joints of low-alloy steels with weakened areas (In Russ.), Avtomaticheskaya svarka, 1989, no. 3, pp. 70-71.

8. GOST 6996-66 (ISO 4136-89, ISO 5173-81, ISO 5177-81). Welded joints. Methods of mechanical properties determination.

9. GOST 25.502-79. Strength analysis and testing in machine building. Methods of metals mechanical testing. Methods of fatigue testing.

10. Yamilev M.Z., Tigulev E.A., Raspopov A.A., The assessment of the level of local strengthening of pipe steel welded connections (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2020, V. 10, no. 3, pp. 252–262,

DOI: https://doi.org/10.28999/2541-9595-2020-10-3-252-262

11. Tigulev E.A., Kantemirov I.F., Estimation of the strength of mechanically inhomogeneous welded connections of main pipelines with a crack-like defect (In Russ.), Problemy sbora, podgotovki i transporta nefti i nefteproduktov, 2021, no. 5(133), pp. 79-88, DOI: https://doi.org/10.17122/ntj-oil-2021-5-79-88

12. Kol’tsun Yu.I., Khibnik T.A., Methods calculation of fatigue crack growth period and her it’s graphic generalization (In Russ.), Vestnik Samarskogo gosudarstvennogo aerokosmicheskogo universiteta im. akademika S.P. Koroleva = Vestnik of the Samara State Aerospace University, 2009, no. 3-2(19), pp. 70-79.

The use of internal epoxy coatings is an effective measure of corrosion protection of pipelines. However, in case of degradation of the coating properties after a certain time or in case of a construction or manufacturing defect of the coatings the operation of pipelines with an internal anti-corrosion coating can cause a significant problem for the operating organization. The service life of pipes with a violation of the integrity of the internal epoxy coating can be from 1 to 3 years. In this article the possibility of pipes inhibitor protection with defects of the internal polymer coating was investigated. The dependences of the coating size defect on the metal corrosion rate are considered. The dosages of the corrosion inhibitor at which there is a significant decrease in the local corrosion rate of samples with coating defects are estimated. It was found that the corrosion rate depends on the size of the coating defect. It is shown that the smaller the size of the coating defect, the higher the corrosion rate due to the localization of corrosion processes in a small area and an increase in the corrosion current density. As a result of the experiments it was found that the efficiency of inhibition of samples with a violation of the integrity of the internal coating in comparison with samples of base metal is significantly lower. A decrease in the corrosion rate of samples with defects occurs at higher dosages of the corrosion inhibitor. An economic calculation confirmed the possibility of pipe inhibition with a violation of the integrity of the internal coating before reconstruction and replacement. An analogy is made between pipes with a violation of the integrity of the internal coating with steel pipelines that fail due to localized corrosion. It has been suggested that in order to decrease local corrosion processes on the inner surface of pipelines, increased dosages of corrosion inhibitors should be used to achieve a corrosion rate not higher than the standard value.

References

1. GOST 9.506-87. Unified system of corrosion and ageing protection. Corrosion inhibitors of metals in water-petroleum media. Methods of protective ability evaluation, Moscow: Publ. of Gostandart, 1987, 16 p.

2. ASTM G59-97(2014). Standard test method for conducting potentiodynamic polarization resistance measurements.

3. ASTM G102-89(2015). Standard practice for calculation of corrosion rates and related information from electrochemical measurements.

4. Halama M., Haluschak E., Hanzes P., Baranova G., The effect of defect size and soil aggressivity on corrosion of underground oil & gas pipelines, Corrosion in the Oil & Gas Industry, 2019, V. 121, no. 01006, DOI: 10.1051/e3sconf/201912101006

5. Adedeji K.B., Ponnle A.A., Abe B.T., Jimoh A.A., Effect of increasing energy demand on the corrosion rate of buried pipelines in the vicinity of high voltage overhead transmission lines, Proceedings of Intl Conference on Optimization of Electrical & Electronic Equipment (OPTIM), 2015, pp. 299–303, DOI: 10.1109/OPTIM.2015.7426749

At the end of 2021 the Rosneft-2030 Strategy: Reliable Energy and Global Energy Transition was approved. The key priorities of the new strategy are reduction of carbon footprint, operational leadership and increased efficiency. The implementation of the Company strategy will contribute to achieving the goals of the Strategy for Socio-Economic Development of the Russian Federation with Low Greenhouse Gas Emissions until 2050, the Paris Agreement on Climate, as well as 17 UN Sustainable Development Goals. In 2019 Rosneft also joined the initiative to reduce methane emissions and signed the Guidelines for the reduction of methane emissions in the natural gas supply chain. One of the horizons of the climate agenda is the reduction of methane emission intensity to less than 0.2% by 2030. Global anthropogenic methane emissions from the energy sector are estimated at 135 million tons, of which about 29% are from natural gas production, processing and transportation processes.

The article considers the results of the assessment of the possible potential to reduce methane emissions at oil and gas production facilities by optimizing the combustion mode of flares by using flareless combustion heads (heads of special design, heads with air supply in the combustion zone). The advantages and limitations of using flare heads of different designs for flareless gas combustion are presented. The methane emission forecast was calculated before and after the implementation of technological solutions for each flare unit. The results were ranked according to the minimum specific costs for the prevention of methane emissions of 1 ton of methane for a fixed period of the project implementation. Calculation of minimum unit costs allows to determine the list of priority flare units for their retrofitting with special design flare heads during the implementation of various scenarios. Generalization of the obtained data makes it possible to carry out quantitative assessment of methane emissions reduction due to using flare heads of special design, to determine priority objects for implementation of technical solutions, to prepare the basis for express-analysis of costs for their realization, to minimize costs due to application of typical solutions, to promptly determine the methane emissions reduction potential, including in changing macroeconomic conditions.

References

1. Crippa M. et al., CO2 emissions of all world countries, Luxembourg: Publications Office of the European Union, 2022, DOI: 10.2760/07904

2. Crippa M. et al., Fossil CO2 emissions of all world countries, Luxembourg: European Commission, 2020, DOI:10.2760/143674

3. Climate change 2013: the physical science basis: Working Group I contribution to the Fifth assessment report of the Intergovernmental Panel on Climate Change: edited by Stocker T. et al., Cambridge University Press, 2014.

4. Roy M., Edwards M.R., Trancik J.E., Methane mitigation timelines to inform energy technology evaluation, Environmental Research Letters, 2015, V. 10, no. 11, DOI: 10.1088/1748-9326/10/11/114024

5. Shindell D. et al., Simultaneously mitigating near-term climate change and improving human health and food security, Science, 2012, V. 335, no. 6065, pp. 183–189, DOI:10.1126/science.1210026

6. Global Methane Tracker 2022, International Energy Agency, 2022, URL: https://www.iea.org/reports/global-methane-tracker-2022/overview

7. URL: https://unfccc.int/ru/news/menee-chem-za-god-chislo-organizaciy-vzyavshikh-na-sebya-obyazatelstva-po...

8. URL: https://www.rosneft.ru/upload/site1/document_file/Rosneft_CSR2021_RUS.pdf

9. Sokrashchenie vybrosov metana. Rukovodstvo po peredovomu opytu produvki (Reducing methane emissions. Purge Best Practice Guide), Methane Guiding Principles, 2019. – https://methaneguidingprinciples.org/wp-content/uploads/2020/12/Reducing-Methane-Emissions-Venting-G...

10. Zardoya A.R. et al., Review about emission reduction in oil extraction using low methane fuels in natural gas combustion engines, International Journal of Applied Sciences: Current and Future Research Trends, 2021, V. 12, no. 1, pp. 53-60.

11. Order of the Ministry of Natural Resources and Ecology of the Russian Federation No. 371 dated 05.27.2022 “Ob utverzhdenii metodik po kolichestvennomu opredeleniyu ob"ema vybrosov parnikovykh gazov i ob’ema pogloshcheniy parnikovykh gazov” (On approval of methods for quantifying the volume of greenhouse gas emissions and the volume of greenhouse gas absorption)

12. Ahsan A. et al., Quantifying the carbon conversion efficiency and emission indices of a lab-scale natural gas flare with internal coflows of air or steam, Experimental Thermal and Fluid Science, 2019, V. 103, pp. 133–142, DOI:10.1016/j.expthermflusci.2019.01.013

13. Order of the State Committee of the Russian Federation for Environmental Protection of April 8, 1998 No. 199 “Metodika rascheta vybrosov vrednykh veshchestv v atmosferu pri szhiganii poputnogo neftyanogo gaza na fakel’nykh ustanovkakh” (Methodology for calculating emissions of harmful substances into the atmosphere from associated petroleum gas combustion at flares), URL: https://docs.cntd.ru/document/1200003953

14. Kang M. et al., Reducing methane emissions from abandoned oil and gas wells: Strategies and costs, Energy Policy, 2019, V. 132, pp. 594–601, DOI:10.1016/j.enpol.2019.05.045

15. URL: https://www.interfax.ru/russia/857669