The Company annually conducts seismic surveys to study the subsoil structure, forecast the material composition and saturation of rocks. Following the growing need to study more complex reservoirs, methods for seismic data interpretation are developing. Attribute analysis and rock physics modeling have become widespread for lithology and reservoir properties forecasting in the interwell space. The basis for rock physics modeling is the mineral component model. In the mineral component model, the components are often a mixture of different minerals due to the limited range of well logging. Therefore, it is required to adjust the grouped constants while rock physics modeling. At the same time, with the basic set of seismic software tools for rock physics modeling, the adjustment of constants and coefficients in models is not automated, and manual adjustment of models is more laborious and less accurate.
This article is devoted to the development of a technique for isotropic rock physics modeling based on well logging and core data supported by inverse modeling (automatic adjustment of coefficients within constraints) to improve the forecast reliability during amplitude interpretation. An integrated approach is considered for curves preparation for amplitude interpretation and mathematic modeling for geological properties forecasting with automation of quality control processes and reliability of the obtained isotropic rock physics models. Approaches are proposed for adjusting the elastic properties in the intervals of well caverns, taking into account caliper readings. A scheme for constructing rock physics isotropic models with additional adjustment of elastic parameters within the constraints, with automated enumeration of combinations of rock physics sub models suitable for the studied section is presentes. The rock physics modeling algorithm was tested with further adjustment of elastic parameters; conclusions were drawn about improving the quality of the final model.
1. Maraev I.A., Kompleksnaya interpretatsiya rezul’tatov geofizicheskikh issledovaniy skvazhin (Comprehensive interpretation of well logging results), Moscow: Publ. of Sergo Ordzhonikidze Russian State University for Geological Prospecting, 2013, 95 p.
2. Mavko G., Mukerji T., Dvorkin J., The rock physics handbook: Tools for seismic analysis in porous media, Cambridge: Cambridge University Press, 2009, URL:
3. Bayuk I.O., Mezhdistsiplinarnyy podkhod k prognozirovaniyu makroskopicheskikh i fil’tratsionno-emkostnykh svoystv kollektorov uglevodorodov (An interdisciplinary approach to predicting the macroscopic and reservoir properties of hydrocarbon reservoirs): thesis of doctor of physical and mathematical science, Moscow, 2013, 228 ð.
4. Shubin A.V., Metodika izucheniya slozhnopostroennykh prirodnykh rezervuarov na osnove petroupurgogo modelirovaniya i inversii seysmicheskikh dannykh (Technique for studying complex natural reservoirs based on petroupurgy modeling and seismic data inversion): thesis of candidate of technical science, Moscow, 2014, 146 ð.
5. Uspenskaya L.A., Modelirovanie uprugikh svoystv porod s uchetom litologicheskogo sostava i tipa zapolnyayushchego flyuida (na primere mestorozhdeniy Urnensko-Usanovskoy zony) (Modeling of elastic properties of rocks taking into account the lithological composition and type of filling fluid (on the example of deposits of the Urnensko-Usanovskaya zone)): thesis of candidate of geological and mineralogical science, Moscow, 2014.
6. Sinyakina Yu.S., Obosnovanie petrofizicheskikh i petrouprugikh modeley tonkosloistykh terrigennykh porod (Substantiation of petrophysical and petroelastic models of thin-layered terrigenous rocks): thesis of candidate of geological and mineralogical science, Moscow, 2017, 152 ð.
7. Kulyapin P.S., Razrabotka interpretatsionnoy i petrouprugoy modeley porod-kollektorov mnogokomponentnogo sostava i slozhnoy struktury emkostnogo prostranstva (Development of interpretative and petroelastic models of reservoir rocks of multicomponent composition and complex structure of capacitive space): thesis of candidate of geological and mineralogical science, Moscow, 2016, 135 ð.
8. Havens J., Mechanical properties of the Bakken formation: the thesis for the degree of Master of Science (Geophysics), Colorado School of Mines, 2012, 109 p.
9. Lavrenkova N.V., Nekrasova T.V., Toropov A.S., Sozdanie petrofizicheskoy osnovy dlya vypolneniya seysmicheskoy inversii – podgotovka dannykh i modelirovanie uprugikh svoystv (Establishment of a petrophysical basis for performing seismic inversion - data preparation and modeling of elastic properties), Proceedings of the BalticPetroModel conference, 2012, URL:
10. Morris G., Nadirov R., Peyn S., Kumar M., Ot modelirovaniya fiziki karbonatnykh porod k 3D prognozirovaniyu ikh tipov por i treshchin v zemnykh nedrakh (From modeling the physics of carbonate rocks to 3D prediction of their types of pores and cracks in the earth’s interior), Proceedings of the BalticPetroModel conference, 2012, https://agora.guru.ru/display.php?conf= petromodel-2012&page =program&PHPSESSID=c00k19d2bevtqfl60qg22dn5r5
11. Fedotov S., Kopytov M., Nekrasova T., Rol’ i znachenie klassicheskoy petrofizicheskoy interpretatsii i sovremennogo modelirovaniya fizicheskikh svoystv gornykh porod (Rock Physics) v prognoze svoystv kollektorov pri pomoshchi metodov seysmicheskikh inversiy (The role and significance of classical petrophysical interpretation and modern modeling of physical properties of rocks (Rock Physics) in the prediction of reservoir properties using seismic inversion methods), Proceedings of the BalticPetroModel conference, 2012, URL:
12. Bayuk I.O., Shekhtman G.A., Petrofizicheskie osnovy mnogovolnovoy seysmorazvedki (Petrophysical foundations of multiwave seismic exploration), Proceedings of the BalticPetroModel conference, 2014, URL: https://agora.guru.ru/ display.php?conf=petromodel&page=conference&PHPSESSID=i3ht6hrbkmuppl0vbqg3j74cc6
13. Nadezhdin O.V., Latypov I.D., Elkibaeva G.G. et al., Sovershenstvovanie metodov atributnogo analiza i petrouprugogo modelirovaniya (Improving the methods of attribute analysis and petroelastic modeling), Moscow: Publ. of Rosneft, 2019.14. Nadezhdin O.V., Efimov D.V., Minikeeva L.R., Markov A.V., Experience with using data analysis technologies in identification of lost production zones (In Russ.), SPE-191597-18RPTC-MS, 2018, https://doi.org/10.2118/191597-18RPTC-MS
More or to buy article
The article is dedicated to the fortieth anniversary of Priobskoye oil field discovery, one of the most unique fields in the Russian Federation. The Priobskoye field belongs to the category of unique not only in terms of reserves, but also in terms of its most interesting development history. 40 years ago, the field was discovered based on the results of testing the exploration well No. 151P, which proved the presence of commercial hydrocarbon reserves. Despite this, this field could not be approached for a very long time due to the inaccessibility of the area, where it was necessary to build infrastructure from scratch, lay roads, pipeline networks and much more, and also, taking into account the fact that most of the reserves belong to the category difficult to recover, the reservoirs are characterized by a very complex geological structure and are characterized by low permeability values. Today it is a whole industrial area with several production and preparation shops, bases of process management and contracting organizations, the largest industrial infrastructure has been created. The development of this field has come a long way, on which, with the acquisition of new knowledge and the development of technologies, the fundamental design solutions and approaches to its development have repeatedly changed. Today, the Priobskoye field is one of the most key fields in our country and Rosneft, providing 13% of its annual Company’s oil production. And besides all this, it is an advanced testing ground and implementation of technologies for the development of ultra-low-permeability reservoirs, the positive results of the pilot work are broadcast to similar areas of the Rosneft Oil Company's fields. The authors provide a brief history and description of the main stages of development, an overview of the reasons that led to fundamental changes and the evolution of project decisions.
1. Veterany geologorazvedki vspomnili, kak bylo otkryto Priobskoe mestorozhdenie (Veterans of exploration remembered how the Priobskoye field was discovered), Novosti Yugry, 2017, no. 4, URL: https://ugra-news.ru/article/ 03042017/46313/
2. Yanin A.N., Hydraulic fracturing is a breakthrough technology! To the 30th anniversary of the beginning of the massive application of hydraulic fracturing in the fields of Western Siberia (In Russ.), Burenie i Neft’, 2018, no. 7, pp. 20–27.
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, https://doi.org/10.24887/0028-2448-2022-5-75-79
More or to buy article
Due to the rapid development of digitalization in the oil and gas industry, new opportunities are becoming available to improve the efficiency of processes: augmented and mixed reality technologies are effectively used not only in scientific research, but also in the production sector. Augmented reality (AR) technology is the mixing of the surrounding reality with virtual objects that are created using computer systems. AR technologies can be used, for example, for inspection of production sites, equipment maintenance, monitoring of technological processes, as well as for personnel training with a more detailed focus on the most important aspects of training and even the formation of skills for working at a hazardous production facility. Oil and gas companies are beginning to actively develop various areas using augmented reality technology in training, remote assistance in complex and dangerous work, quality control of work, as well as the ability to have quick access to expert advice or knowledge bases. Augmented reality technologies can be used both by highly qualified specialists, engineers, and workers. In practice, AR technologies are implemented in the form of interactive simulators, special mobile applications and computer models, and the increasing number of devices worn by employees, such as smartphones and tablets, further contributes to the introduction of augmented reality in the industry. The combination of augmented reality with other promising technologies, such as the Internet of Things, big data and artificial intelligence, provides significant advantages for creating more holistic technical solutions.
The article discusses the development of training AR simulators, which are used to form the skills, reduce risks in the performance of work at hazardous production facilities, as well as to prevent emergencies. The use of augmented reality for these purposes is particularly relevant and opens up prospects for a significant increase in efficiency in learning processes due to flexibility and fine-tuning of training for each employee.
1. Isachenko N.N., Khismatullina I.Z., Augmented reality as one of the modern technological trends in the oil industry (In Russ.), Nauchnoe obozrenie, 2018, no. 1, p. 13.
2. Koroleva O.B., Evaluation of the effectiveness of personnel training (In Russ.), Kontrol’ kachestva produktsii, 2009, no. 5, pp. 12–15.
3. Frolov V.A., Perspektivy ispol’zovaniya tekhnologii dopolnennoy real’nosti v promyshlennosti (Prospects for the use of augmented reality technology in industry), Proceedings of IX international scientific and practical conference “Innovatsionnoe razvitie rossiyskoy ekonomiki” (Innovative development of the Russian economy), Moscow, 2016, pp. 304–305.
4. Certificate of official registration of the computer program no. 2021665813, Programmnyy kompleks obuchayushchikh trenazherov dopolnennoy real’nosti (Augmented reality training simulator software package), Authors: Katermin A.V., Palaguta A.A., Enikeev R.M., Shubin S.S., Khabibullin R.R., Zakirov V.F., Kurshev A.V., Anpilogov A.V., Il’in K.O., Mardanov S.Kh., Beloborodova E.V., Golubev E.M., Zaykin A.M.
5. Zenkevich A., Digital technologies for training production personnel (In Russ.), Control engineering Rossiya, 2018, no. 6(78), pp. 68-71.
6. Dorozhnaya karta razvitiya “skvoznoy” tsifrovoy tekhnologii “Tekhnologii virtual’noy i dopolnennoy real’nosti” (Roadmap for the development of “end-to-end” digital technology “Virtual and Augmented Reality Technologies”), URL: http://www.consultant.ru/document/cons_doc_LAW_335562/
7. Khabibullina S.A., Kozlova E.M., Building a training system in the company (In Russ.) Upravlenie razvitiem personala, 2009, no. 3(19), pp. 198–204.8. Muzipov Kh.N., Kolupaev S.A., Technology of augmented reality (In Russ.), Avtomatizatsiya, telemekhanizatsiya i svyaz’ v neftyanoy promyshlennosti, 2015, no. 7, pp. 9–11.
More or to buy article
The article is devoted to the implementation of an integrated approach to the process of testing new technologies in the areas of well bottomhole treatment (BWT) and repair and insulation operations (RIW) in Rosneft Oil Company. Implementation of comprehensive approach to optimize the process of selection, testing and implementation of new technologies is described. The authors highlight peculiarities of geological and physical conditions of the productive objects depending on oil and gas bearing province, describe basic technologies of BWT and reservoir treatment, defines the conditions influencing the efficiency of their application. Priority directions of technological development, such as flow enhancement in low-permeable or low-temperature cavernous-cracked carbonate reservoirs, bottomhole treatment of objects confined to hard-to-recover reserves, as well as limitation of water and gas inflow through the productive formation and restoration of casing and cement ring integrity in conditions of long unsealed intervals were formed. Optimized procedure for pilot testing of BTW and RIW technologies is given, it consist of seven main stages from identifying the problem of the basic technology application to replication of the results in the Rosneft Oil Company. Classification of methods of impact on the bottomhole formation zone was also made, a set of necessary research works was determined, standard forms of testing programs were developed, basic criteria and forecast performance indicators were determined, scientific and methodological support of new technologies testing was provided. A number of examples of successful testing of BWT technologies (with chemical flow deviation in heterogeneous carbonate reservoirs, with the use of delayed acid compositions, with the use of modified acid compositions for low-temperature cavernous-cracked carbonate reservoirs, as well as technologies for low-permeability terrigenous reservoirsand) and RIF technologies (limiting water inflow in monolithic terrigenous reservoirs, as well as complex technologies in horizontal wells) are given. The prospects for the development of areas in the Rosneft Oil Company are noted.
1. Folomeev A.E., Vakhrushev A.S., Mikhaylov A.G., On the optimization of acid compositions for geotechnical conditions of oilfields of Bashneft JSOC (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 11, pp. 108-111.
2. 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.
3. Folomeev A.E., Vakhrushev S.A., Khatmullin A.R. et al., Reducing the negative impact of workover fluids on Sorovskoe oilfield sandstone formation by their modification (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta. Inzhiniring georesursov, 2022, V. 333, no. 2, pp. 26–37, https://doi.org/10.18799/24131830/2022/2/3328
4. Kraynov M.V., Goryachev S.E., NK Rosneft actual problems and solutions in the repair and insulation works and water shut-off (In Russ.), Inzhenernaya praktika, 2014, no. 5, pp. 104–106.
5. Nikulin V.Yu., Nigmatullin T.E., Mikhaylov A.G. et al., Selection of insulation compositions and technologies for horizontal wells under difficult conditions (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 10, pp. 96–101, https://doi.org/10.24887/0028-2448-2021-10-96-101
6. Nigmatullin T.E., Nikulin V.Yu., Shaymardanov A.R. et al., Water-and-gas shutoff technologies in horizontal wells on north komsomolskoe field: Screening and successful trial, SPE-206496-MS, 2021, https://doi.org/10.2118/206496-MS
7. Nigmatullin T.E., Shaymardanov A.R., Akhankin I.B., Repair-insulation works that provide conducting of geological-technical measures in order to increase oil production (by the example of LLC "RN-Uvatneftegaz") (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2017, no. 12, pp. 63–68.
8. Shaydullin V.A., Levchenko E.A., Valieva O.I., Akhmerov I.A., Selection of grouting compositions for water shut-off in low-permeability intervals (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 6, pp. 94–98, https://doi.org/10.24887/0028-2448-2019-6-94-98
9. Sakhan' A.V., Shcherbakov D.P., Vorob'ev S.A. et al., The use of fiberglass scab liner to restore casing integrity (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 11, pp. 132–136, https://doi.org/10.24887/0028-2448-2017-11-132-136
10. Suchkov B.M., Intensifikatsiya raboty skvazhin (Well stimulation), Moscow - Izhevsk: Publ. of Institute for Computer Research, 2007, 612 p.
11. Loginov B.G., Malyshev L.G., Garifullin Sh.S., Rukovodstvo po kislotnym obrabotkam skvazhin (Guide to acid treatment of wells), Moscow: Nedra Publ., 1966, 220 p.
12. Umetbaev V.G., Merzlyakov V.F., Volochkov N.S., Kapital'nyy remont skvazhin. Izolyatsionnye raboty (Workover. Insulation works), Ufa: Publ. of Bashneft, 2000, 424 p.
13. Litvinenko K.V., Valiakhmetov R.I., Integrated engineering services as a factor in improving the efficiency of oil production (In Russ.), Inzhenernaya praktika, 2021, no. 7, pp. 60–69.
14. Bulgakova G.T., Kharisov R.Ya., Sharifullin A.R., Pestrikov A.V., Simulator for optimizing extended selective acidizing in carbonate formations designs (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “Rosneft'”, 2010, no. 2, pp. 16‒20.
15. Harrison N.W., Diverting agents – History and application, JPT, 1972, V. 24(5), pp. 593 – 598, https://doi.org/10.2118/3653
16. Hill A.D., Rossen W.R., Fluid placement and diversion in matrix acidizing, SPE-27982-MS, 1994, https://doi.org/10.2118/27982-MS
17. Folomeev A.E., Taipov I.A., Khatmullin A.R. et al., Gelled acid vs. self-diverting systems for carbonate matrix stimulation: an experimental and field study, SPE-206647-MS, 2021, https://doi.org/10.2118/206647-MS
18. Imamutdinova A.A., Khatmullin A.R., Folomeev A.E., Optimizatsiya tekhnologii kislotnogo vozdeystviya dlya usloviy vysokotemperaturnykh terrigennykh kollektorov (Optimization of acid treatment technology for high-temperature terrigenous reservoirs), Collected papers “Prakticheskie aspekty neftepromyslovoy khimii” (Practical aspects of oilfield chemistry), Proceedings of scientific and practical conference, Ufa: Publ. of Fund of support and development of science of the Republic of Bashkortostan, 2022, pp. 57-58.
19. Shaydullin V.A., Kamaletdinova R.M., Yakupov R.F. et al., Selecting the water shut-off technology for monolithic terrigenous formations (In Russ.), Neft'. Gaz. Novatsii, 2021, no. 7, pp. 34–38.
20. Morikov I.P., Sakhan' A.V., Shcherbakov D.P. et al., Practical experience in water shut-off treatments planning and realization (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 11, pp. 62–64.
21. 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. 112–117.22. Shaydullin V.A., Nigmatullin T.E., Magzumov N.R. et al., Analysis of advanced waterproofing technologies in gas wells (In Russ.), Neftegazovoe delo, 2021, no. 1, pp. 51–60.
More or to buy article
A significant number of the largest oil fields in Russia are at a late stage of development. Operation of low-flow wells is carried out mainly by sucker-rod pump units. Timely diagnostics of the technical condition and operating conditions of pumping equipment is an important condition for ensuring cost-effective well development. The article considers a new approach to the diagnosis of sucker-rod pump units based on mathematical modeling of their operation and the construction of theoretical dynamometer cards. By varying the parameters characterizing the complicating factors, the configurations of dynamometer cards during the operation of pumping equipment under various conditions (leaks in the discharge and receiving parts of the pump, high and low fit of the plunger in the cylinder) are analyzed. It has been found that leaks through the pump valves have a significant impact on the configuration of the load and discharge lines of the pumping rods on the dynamometer cards, and with an increase in volumetric supply losses due to leaks in the discharge valve, the length of the load perception line increases. An increase in supply losses due to leaks in the suction valve leads to an increase in the length of the rod discharge line. It is shown that the estimation of the volume of leaks through the pump valves according to the dynamometer cards makes it possible to make an informed decision on optimizing the operation mode of the well, conducting underground repairs. The configuration of dynamometer cards at a high landing with the plunger exiting the pump cylinder, the plunger hitting the suction valve cage at the end of the downward stroke at a low landing is analyzed. It is shown that the construction of theoretical dynamometer cards and their comparison with the actual one makes it possible to calculate the stroke length of the polished rod, accompanied by the output of the plunger from the cylinder (the impact of the plunger on the suction valve cage). For the considered examples, the principles of solving the problems of quantitative diagnostics and issuing recommendations for adjusting the technological regime in order to optimize it are shown. The developed approach is aimed at increasing the information content of diagnostics and monitoring of sucker-rod pump units according to the wellhead dynamogram, which is especially important for wells operating in complicated operating conditions.With the help of a mathematical model, by approximating the calculated dynamogram to the actual one, it is possible to assess the criticality of complicating factors and further optimize the operating mode of the rod installation.
1. Volkov M.G., Khalfin R.S., Topol’nikov A.S. et al., Approaches to justification of selection of the application field for new artificial lift method (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 3, pp. 96-100, https://doi.org/10.24887/0028-2448-2019-3-96-100
2. Timashev E.O., Khalfin R.S., Volkov M.G., Statistical analysis of the failure times and feed rates of downhole pumping equipment in operating parameter ranges (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 2, pp. 46-49, https://doi.org/10.24887/0028-2448-2020-2-46-49
3. KKovshov V.D., Sidorov M.E., Svetlakova S.V., Dynamometry, modelling and diagnostic the condition of rod pump (In Russ.), Izvestiya vuzov. Neft’ i gaz, 2011, no. 3, pp. 25–29.
4. Li K., Han Y., Wang T., A novel prediction method for down-hole working conditions of the beam pumping unit based on 8-directions chain codes and online sequential extreme learning machine, Journal of Petroleum Science and Engineering, 2018, V. 160, pp. 285-301, https://doi.org/10.1016/j.petrol.2017.10.052
5. Urazakov K.R., Bakhtizin R.N., Ismagilov S.F., Topol'nikov A.S., Theoretical dynamometer card calculation taking into account complications in the sucker rod pump operation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 1, pp. 90–93
6. Bakhtizin R.N., Urazakov K.R., Timashev E.O., Belov A.E., A new approach of quantifying the technical condition of rod units with the solution of inverse dynamic problems by multidimensional optimization methods (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 7, pp. 118–122, https://doi.org/10.24887/0028-2448-2019-7-118-122
7. Urazakov K.R., Timashev E.O., Tugunov P.M., Davletshin F.F., Study on efficiency of rod unit with combined fiberglass rod string (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 7, pp. 123-127, https://doi.org/10.24887/0028-2448-2019-7-123–127.
8. Chen Z., White L.W., Zhang H., Predicting sucker-rod pumping systems with Fourier series, SPE 189991-PA, 2018, https://doi.org/10.2118/189991-PA.
9. Timashev E.O., Urazakov K.R., Lushnikov A.V., Evdokimov D.K., Optimization of the technological mode of rod unit with combined fiberglass rod string (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 1, pp. 57-61, https://doi.org/10.24887/0028-2448-2021-1-57-61
10. Akramov T.F., Yarkeeva N.R., Control deposits of paraffin, asphalt-resin components of oil (In Russ.), Neftegazovoe delo, 2017, V. 15, no. 4, pp. 67-72.
11. Hansen B., Tolbert B., Vernon C., Hedengren J.D., Model predictive automatic control of sucker rod pump system with simulation case study, Computers and Chemical Engineering, 2019, V. 121, pp. 265–284, https://doi.org/10.1016/j.compchemeng.2018.08.018
12. Bakhtizin R.N., Urazakov K.R., Ismagilov S.F. et al., Dynamic model of a rod pump installation for inclined wells, Socar Proceedings, 2017, no. 4, pp. 74–82, https://doi.org/10.5510/OGP20170400333
13. Zyuzev A.M., Tekle S.I., Sucker rod pumping system: Challenges to develop diagnostic system and role of dynamic simulator (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta. Inzhiniring georesursov, 2022, V. 333, no. 1, pp. 168-177, https://doi.org 10.18799/24131830/2022/1/328514. Kovshov V.D., Svetlakova S.V., Sidorov M.E., The dynamometer card of well pumping unit modeling. Valves' leakages (In Russ.), Neftegazovoe delo, 2005, no. 3, pp. 47-54.
More or to buy article
54.06, 622.276, 620.193
The authors proposed an X-ray phase analysis (XPA) approach, which makes it possible with improved statistics to identify and quantitatively estimate the ultrafine grained solids phase composition. As a result of a new survey approach, which consists in shooting an averaged diffraction pattern from a series of measurements obtained at different azimuth angles of the sample inclination, it became possible to more accurately estimate the ultrafine grained solid’ weight fraction with a low content. In this paper, we consider the extension of the capabilities the proposed XPA approach and its application for mineral deposits analysis in oilfield equipment’s ferritic-martensit steel. It has been established that the conventional method of measuring x-ray patterns on Cu radiation leads to their fluorescence, in which the present phases’ diffraction reflections are significantly absorbed, as a result of which the x-ray patterns’ interpretation often leads to erroneous results. Based on a theoretical analysis the parameters that make it possible to control the intensity of detected X-ray quanta, ways are shown to obtain optimal x-ray patterns from the point of view the reflections intensity ratio and background radiation. An algorithm for quantitative evaluation phases is shown as a result of refinement the shape and size of crystallites, crystallographic texture, Debye – Waller factor, evolutions of atoms on crystal lattice and their displacements. To assess the accuracy and reliability the obtained data, for the first time the XPA quantitative results were recalculated into oxide forms and compared with the data of x-ray fluorescence spectrometry, which showed their convincing convergence. For additional verification of obtained results, scanning electron microscopy methods were used. The proposed approach makes it possible to obtain extended information about the type and quantitative ratio of phases, which opens up new opportunities for studying the corrosion mechanisms and scaling on oilfield equipment steels.
1. Markin A.N., Sukhoverkhov S.V., Brikov A.V., Neftepromyslovaya khimiya: analiticheskie metody (Oilfield chemistry: Analytical methods), Yuzhno-Sakhalinsk: Sakhalin Regional Printing House, 2016, 212 p.
2. Brikov A.V., Markin A.N., Neftepromyslovaya khimiya: prakticheskoe rukovodstvo po bor'be s obrazovaniem soley (Oilfield chemistry: A practical guide to salt control), Moscow: De Libri Publ., 2018, 335 p.
3. Ibragimov N.G. et al., Oslozhneniya v neftedobyche (Complications in oil production): edited by Ibragimov N.G., Ishemguzhin E.I., Ufa : Monografiya Publ., 2003, 302 p.
4. Puchina G.R., Ragulin V.V., Voloshin A.I. et al., Neftepromyslovaya khimiya. Sovremennye metody bor'by s soleotlozheniyami v dobyche nefti (Oilfield chemistry. Modern methods of scaling control in oil production), Ufa: Bashkirskaya entsiklopediya Publ., 2020, 72 p.
5. Volkov M.G., Presnyakov A.Yu., Klyushin I.G. et al., Monitoring and management the abnormal well stocks based on the Information System Mekhfond of Rosneft Oil Company (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 2, pp. 90–94, https://doi.org/10.24887/0028-2448-2021-2-90-94
6. Sitdikov V.D., Nikolaev A.A., Kolbasenko E.A. et al., A new approach to the analysis of clay minerals in rocks by X-Ray scattering (In Russ.), Neftegazovoe delo, 2021, V. 19, no. 5, pp. 75–83, https://doi.org/10.17122/ngdelo-2021-5-75-83
7. Gorelik S.S, Skakov Yu.A., Rastorguev L.N., Rentgenograficheskiy i elektronno-opticheskiy analiz (X-ray and electron-optical analysis), Moscow: Publ. of MISIS, 1994, 328 p.
8. Nakhmanson M.S., Feklichev V.G., Diagnostika sostava materialov rentgendifraktsionnymi i spektral'nymi metodami (Diagnostics of the composition of materials by X-ray diffraction and spectral methods), Leningrad: Mashinostroenie Publ., 1990, 356 p.
9. Sitdikov V.D., Nikolaev A.A., Ivanov G.V. et al., Microstructure and crystallographic structure of ferritic steel subjected to stress-corrosion cracking (In Russ.) Pis'ma o materialakh, 2022, V. 12, no. 1, pp. 65–70.
10. Zevin L.S., Kimmel G., Quantitative X-ray diffractometry, Springer Science & Business Media, 2012, 372 p.
11. Sitdikov V.D., Murashkin M.Yu., Valiev R.Z., New X–ray technique to characterize nanoscale precipitates in aged aluminium alloys, J. Mater. Eng. Perform., 2017, V. 26, no. 10, pp. 4732–4737, https://doi.org/10.1007/s11665-017-2915-0
12. Zhou S., Potzger K., Talut G. et al., Using X–ray diffraction to identify precipitates in transition metal doped semiconductors, J. Appl. Phys., 2008, V. 103(7), https://doi.org/10.1063/1.2828710
13. Rietveld H.M., A profile refinement method for nuclear and magnetic structures, J. Appl. Crystallogr., 1969, V. 2, pp. 65–71, https://doi.org/10.1107/S0021889869006558
14. Snellings R., Machiels L., Mertens G., Elsen J., Rietveld refinement strategy for quantitative phase analysis of partially amorphous zeolitized tuffaceous rocks, Geologica Belgica, 2010, V. 13/3, pp. 183–196.
15. Dollase W.A., Correction of intensities for preferred orientation in powder diffractometry: application of the March model, Journal of Applied Crystallography, 1986, V. 19, pp. 267-272, https://doi.org/10.1107/S0021889886089458
16. Para T.A., Sarkar S.K., Challenges in rietveld refinement and structure visualizatio in ceramics, In: Advanced Ceramic Materials, London, United Kingdom: IntechOpen, 2021, 296 ð., https://doi.org/10.5772/intechopen.96065n17. Zeng Z., Lu H., Zhao Y., Qin Y., Analysis of the mineral compositions of swell-shrink claysfrom Guangxi province, China, Clays and Clay Minerals, 2020, V. 68, pp. 161–174, https://doi.org/10.1007/s42860-019-00056-7
More or to buy article
The article presents the developments of RN-BashNIPIneft LLC in researches of microstructure, crystallographic texture, level and anisotropy of material strength properties, the integral analysis of which helps to establish the destruction causes and mechanisms of pipes used in the oil industry. To solve these tasks, it is suggested to combine the methods of scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), X-ray fluorescence analysis and computer modeling. As a result of the comparative analysis of the information on the internal structure of the material in the areas exposed to corrosion, the mechanisms and causes of their destruction are revealed. This work shows that on examining the fracture and microcracks nature, determining the size and type of non-metallic inclusions, the average size and mutual orientation of grains, the elemental composition of corrosion products by the SEM method established the destruction of a pump and compressor pipe (tubing) by stress corrosion cracking (SCC) mechanism. The use of X-ray method determines that the preferred grain orientations formed during tubing forming in the fracture zone and in the crack-free zone are significantly different. As a result of analyzing the texture formation processes, it was found that in the upper layers of the tubing near the fracture zone, there are the traces of restoring and recrystallization processes, which led to local softening of the tubing while molding. At the same time, the violations of the technological modes of molding were detected, which led to the formation of a homogeneous type of crystallographic texture up to half the thickness of the tubing wall, which led to a resistance decrease of the material and the spread of microcracks. In other areas where there are no traces of SCC, the various types of crystallographic texture along the entire thickness of the tubing wall were revealed. As a part of the analysis of texture coefficients and making 2D projections of the yield surfaces, a relatively low value of the yield strength in the fracture zone in the direction of the longitudinal axis of the tubing was established. As a result, the authors make a conclusion that the local softening of the material, selectively homogeneous crystallographic texture along the pipe wall thickness, as well as a low level and strong anisotropy of the strength properties on the outer surface of the wall, led to the appearance and propagation of the cracks along the longitudinal axis of the tubing being under pressure.
1. Tkacheva V.E., Markin A.N., Kshnyakin D.V. et al., Corrosion of downhole equipment in hydrogen sulfur-containing environments (In Russ.), Praktika Protivokorrozionnoy Zashchity, 2021, V. 26(2), pp. 7–15, https://doi.org/10.31615/j.corros.prot.2021.100.2-1
2. Okyere M.S., Corrosion protection for the oil and gas industry: Pipelines, subsea equipment, and structures, CRC Press, 2019, 186 p.
3. Medvedeva M.L., Korroziya i zashchita ot korrozii oborudovaniya pri pererabotke nefti i gaza (Corrosion and corrosion protection of the equipment in the of oil and gas refining), Moscow: Neft' i Gaz Publ., 2013, 250 p.
4. Kocks U.F., Tomé C.N., Wenk H.-R., Texture and anisotropy. Preferred orientations in polycrystals and their effect on material properties, Cambridge University Press, 1998, 688 p.
5. Raabe D., Lüucke K., Textures of ferritic stainless steels, Mater.Sci. Technol., 1993, no. 9, pp. 302–312, https://doi.org/10.1179/mst.1922.214.171.1242.
6. Raabe D., Overview on basic types of hot rolling textures of steels, Steel research International, 2003, V. 74, pp. 327–337, https://doi.org/10.1002/srin.200300194.
7. Sitdikov V.D., Nikolaev A.A., Ivanov G.V. et al., Microstructure and crystallographic structure of ferritic steel subjected to stress-corrosion cracking (In Russ.), Pis'ma o materialakh = Letters on Materials, 2022, no. 12 (1), pp. 65–70, https://doi.org/10.22226/2410-3535-2022-1-65-70.8. Perlovich Yu.A., Isaenkova M.G., Dobrokhotov P.L. et al., Regularities of texture formation in cladding tubes made from ferritic-martensitic steels on different manufacturing stages (In Russ.), Voprosy atomnoy nauki i tekhniki. Seriya: Materialovedenie i novye materialy, 2017, no. 4(91), pp. 74–83.
More or to buy article
The pipeline transportation of naphthene-base crude from the Russkoye field is complicated by the abnormally high viscosity and density of wellstream. For this oil gathering and trouble-free inter-field transport, it is necessary to use special methods that ensure a decrease in viscosity. The pipeline transport of naphthene-base crude from the Russkoye field is also complicated by climatic conditions (low temperatures), especially in case of above ground pipelining. When the temperature of viscous oil transport decreases to the temperatures of the beginning of paraffin crystallization, a solid phase begins to appear in the pumped liquid - crystals of paraffin-like conglomerates adhering to the inner surface of the pipeline. On oil pipelines pumping rheologically complex oil, special pumping technologies are traditionally used. To reduce oil viscosity and pour point, additives of various types or crude mixture with light oil and/or gas condensates produced in nearby regions are used.
The article considers the viscosity-temperature features of oil and gas condensate mixtures produced by the wells of the Russkoye field. The regulation of phase transitions is carried out by the introducing into the oil system gas condensate, which is produced in large volumes at the Russkoye field. The study of the rheological characteristics of the initial oil and gas condensate, and their blends were allowed to determine the optimal ratio of the pumped-over fluids for the safe pipeline transport. The results of studying the differential pressure in the dynamic mode of modeling the pumping of oil and its mixtures with gas condensate under conditions of a gradual decrease in temperature confirmed the data of the rheological determination of the temperature of the onset of paraffin crystallization in a mixture with a naphthenic-oil fraction. The effectiveness of inhibiting the formation of asphalten-resin-paraffin deposits in the pumped liquid stream has also been confirmed by the Cold Finger test.
1. Kashirtsev V.A., Nesterov I.I., Melenevskiy V.N. et al., Biomarkers and adamantanes in crude oils from Cenomanian deposits of northern West Siberia (In Russ.), Geologiya i geofizika = Russian Geology and Geophysics, 2013, V. 54, no. 8, pp. 1227–1235.
2. Baklanova O.N., Lavrenov A.V., Kashirtsev V.A. et al., Isolation of adamantane hydrocarbons from Cenomanian oil of the Russkoe oilfield (In Russ.), Neftekhimiya = Petroleum Chemistry, 2016, V. 56, no. 2, pp. 115–119, https://doi.org/10.7868/S0028242116020039
3. Pevneva G.S., Fursenko E.A., Voronetskaya N.G. et al., Hydrocarbon composition and structural parameters of resins and asphaltenes of naphthenic oils of northern West Siberia (In Russ.), Geologiya i geofizika = Russian Geology and Geophysics, 2017, V. 58, no. 3–4, pp. 522–532, https://doi.org/10.15372/GiG20170315
4. Shafikova E.A., Belenkova N.G., Arslanova I.M. et al., The application of depressant additives in the transport of high-paraffin oil (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 10, pp. 90–93, https://doi.org/10.24887/0028-2448-2020-10-90-93
5. Fiziko-khimicheskie svoystva neftyanykh dispersnykh sistem i neftegazovye tekhnologii (Physico-chemical properties of oil dispersed systems and oil and gas technology): edited by Safieva R.Z., Syunyaev R.Z., Moscow – Izhevsk: Publ. of Institute of Computer Science, 2007, 580 p.
6. Petrov Al.A., Uglevodorody nefti (Petroleum hydrocarbons), Moscow: Nauka Publ., 1984, 260 p.
7. Fuks G.I., Vyazkost' i plastichnost' nefteproduktov (Viscosity and plasticity of petroleum products), Mosocw: Publ. of Institute for Computer Research, 2003, 328 p.
8. Kuz'menko O.S., Kul'kov M.G., Korzhov Yu.V., Nekhoroshev S.V., The study of the effect of precipitating N-hexane in the oil asphaltenes West Salym (In Russ.), Vestnik Yugorskogo gosudarstvennogo universiteta, 2016, no. 3 (42), pp. 26–34.9. Evdokimov I.N., Problemy nesovmestimosti neftey pri ikh smeshenii (Oil incompatibility problems during oil mixing), Moscow: Publ. of Gubkin Russian University of Oil and Gas, 2008, 93 p.
More or to buy article
The article presents the results of the geological structure analysis and oil and gas potential of the Laptev Sea shelf. The state of exploration of the water area and the continental shelf framing by complex geological and geophysical methods and well drilling is considered. It is shown that the seismic exploration degree of the shelf is low, and deep drilling was carried out mainly on land, where small Permian oil deposits were discovered. Only one well (Tsentralno-Olginskaya-1) was drilled in Khatanga Bay (starting from Bolshoy Begichev Island) which discovered a large oil field also in Permian deposits. The issues related to tectonics, stratification of sedimentary complexes and the age of the folded basement of the Laptev Sea shelf remain controversial due to the lack of information. This owes to the fact that the regional stage of geological exploration has not been completed. Based on the analysis of geological materials, the authors concluded that the Khatanga, Pritaimyr and Omoloy structural-formation zones have the highest oil and gas potential in which Cenozoic delta deposits join with Upper Paleozoic-Mesozoic blocks Lithological hydrocarbon traps may be associated with paleodelts. There is a possibility of the hydrocarbon discovery in Paleozoic deposits stretching into the shelf as a part of an intermediate structural level. For the purpose of regional geological exploration it was proposed to perform 2D seismic with a high density of seismic profiles network and drill a parametric well into Mesozoic deposits in the Khatanga transition zone. Prospecting and evaluation drilling is recommended at the Begichevskaya structure with maximum exposing of terrigenous Permian deposits. The technological capabilities and directional drilling experience of the largest oil and gas companies make such project possible and solve the set of geological problems including hydrocarbon reserves appraisal in the Laptev Sea at a qualitatively new level.
1. Shkarubo S.I., Zavarzina G.A., Zuykova O.N. et al., Shel’fovye osadochnye basseyny Rossiyskoy Arktiki: geologiya, geoekologiya, mineral’no-syr’evoy potentsial (Shelf sedimentary basins of the Russian Arctic: geology, geoecology, mineral resource potential), St. Petersburg: Renome Publ., 2020, 544 p.
2. Pronkin A.P., Savchenko V.I., Shumskiy B.V., Prospects for the oil and gas potential of the Khatanga Bay (In Russ.), Offshore Russia, 2013, September, pp. 18–22.
3. Pronkin A.P., Savchenko V.I., Stupakova A.V. et al., New data on the geological structure and oil and gas potential of the Khatanga mesodepression and the adjacent water area of the Laptev Sea (In Russ.), Prirodnye resursy Krasnoyarskogo kraya, 2014, no. 23, pp. 57–62.
4. Vasil’eva E., Ponina V., Petrushina E., Sadovnikov A., Prospects for oil and gas potential in the southwestern part of the Laptev Sea (In Russ.), Offshore Russia, 2017, May, pp. 18–22.
5. Dzyublo A.D., Nikitin B.A., Prospects for development of Russian Arctic offshore gas resources (In Russ.), Vestnik gazovoy nauki, 2017, no. 4, pp. 15–24.
6. Skvortsov M.B., Dzyublo A.D., Grushevskaya O.V. et al., Laptev Sea shelf: qualitative and quantitative assessment of hydrocarbon potential (In Russ.), Geologiya nefti i gaza, 2020, no. 2, pp. 34–44, https://doi.org/10.31087/0016-7894-2020-1-5-19
7. Dzyublo A.D., Neftegazonosnost’ i geologo-geofizicheskie modeli shel’fa Rossiyskoy Arktiki i Dal’nego Vostoka (Oil and gas potential and geological and geophysical models of the shelf of the Russian Arctic and the Far East), Publ. of Gubkin University, 2018, 235 p.
8. Daragan-Sushchova L.A., Petrov O.V., Daragan-Sushchov Yu.I., Rukavishnikova D.D., A new look at the geological structure of sedimentary cover of the Laptev Sea (In Russ.), Regional’naya geologiya i metallogeniya, 2010, no. 41, pp. 5–17.
9. Mel’nikov P.N., Skvortsov M.B., Kravchenko M.N. et al., Geological exploration in the Arctic: resource potential and promising areas (In Russ.), Neftegaz.RU, 2020, no.1(97), pp. 22-30.
10. Mel’nikov P.N., Skvortsov M.B., Kravchenko M.N. et al., The results of geological exploration on the Russian Arctic shelf in 2014–2019 and prospects for future development (In Russ.), Geologiya nefti i gaza, 2019, no. 6, pp. 33–46, https://doi.org/10.31087/0016-7894-2019-6-5-1811. Savchenko V.I., Stupakova A.V., Peretolchin K.A., The prospects of large oil and gas fields in the Eastern Taimyr (In Russ.), Georesursy = Georesources. 2017, Special issue, Part 2, pp. 186-193, http://doi.org/10.18599/grs.19.19
More or to buy article
The paper reveals the prerequisites for the creation of import-substituting
geoinformation system (GIS) solutions in face of evolving digitalization and
adverse international conditions. The results of the development of the corporate
GIS as well as its functionality and application are presented generated
on the basis of Rosneft Oil Company. The article describes the main purpose
of corporate GIS, its technological platform, based on the corporative
GIS strategy, presents the scale of corporate GIS distribution in the Rosneft
Company. The overall effect of the geodata systematization was considered
both for the local branches and for the whole Rosneft Oil Company as a part
of the corporate GIS benefits analysis. The upper-level components of the
system consisting of the basic GIS platform and specialized modules are described.
The paper gives in detail the functionality of modules automating a
wide range of engineering design tasks from an initial investment planning to
final design solutions for oil and gas production facilities. The functionality includes
the tools for such processes as conceptual design, pre-design study,
engineering surveys (including monitoring of field work and drawing of topographic
maps), design of oil and gas facilities, as well as visualization and
analysis of spatial data at all stages of design. In conclusion the paper presents
the possible benefits and results of widespread corporate GIS implementation
in Rosneft Oil Company subsidiaries, reveals the main perspectives
of future development and new directions for further GIS automation of
the Company business processes.
More or to buy article
Gecon LLC - 30 years!
More or to buy article
The experience of drilling the horizontal and subhorizontal wells in the Achimov deposits interval demonstrates a high risk of complications and accidents. This relates to the complexity of geological factors, anomalously high reservoir pressure and narrow safe density interval. At the present time, there is no consensus on the reasons of borehole wall disturbances in the Achimov rock interval. Some researchers consider a mechanical impact of drill pipes on borehole walls, while the others reckon among the main factors the tripping of borehole walls, their physical and chemical interaction with the flush liquid, the mechanical impact of drilling tool and the stress state of the rocks. The friction forces between the rock particles are also emphasized as the reason of borehole wall disturbances. One of the reasons for the strength degradation of clay material is the process drill mud penetration, which causes the emergence of the disjoining pressure in the rock and the borehole wall disturbance. Thus, notwithstanding a major number of researches related to the borehole wall strengthening in the Achimov deposits interval, this issue remains unresolved and requires a further research.
The article presents the plan of actions reducing the risk of complications and accidents while drilling the horizontal wells at Lutseyakhoye field. The first stage is geomechanical modelling of borehole wall stability, which allows to define a window of drill mud safe density throughout the whole wellbore. The second stage is updating the hydraulic program defining the borehole cleaning from drill cuttings and the selection of the best rheological parameters. The third stage is working out drilling mud composition to drill in the Achimov deposit intervals. While assessing the non-productive drilling time (NPT) for the Achimov deposits of the adjoining fields, it was established that the average NPT is 23 days. The complex approach to accident-free drilling of horizontal wells made it possible to reduce NPT based on geological factors to 3 days.
1. Petrova N.V., Ershov S.V., Kartashova A.K., The geological structure and hydrocarbon prospects of Achimov strata in Western-Nerutinsk petroleum area (In Russ.), Geologiya nefti i gaza, 2018, no. 2, pp. 41–50.
2. Khubbatov A.A., Gaydarov A.M., Norov A.D., To the question of the stability of clay rocks (In Russ.), Territoriya neftegaz, 2014, no. 5, pp. 22–32.
3. Gorbunov S.A., Nezhdanov A.A., Ponomarev V.A., Turenkov N.A., Geologiya i neftegazonosnost' achimovskoy tolshchi Zapadnoy Sibiri (Geology and oil and gas content of the Achimov strata of Western Siberia), Moscow: Publ. of Academy of Mining Sciences, 2000, 247 p.
4. Dobrokhleb P., Ablaev A., Chetverikov D. et al., Best practice of horizontal well construction operations for the challenging, high-pressure Achimov formation of Urengoyskoe field, SPE-171265-MS, 2014, https://doi.org/10.2118/171265-MS
5. Dobrokhleb P.Yu., Kretsul V.V., Dymov S.Yu. et al., Engineered drilling system approach makes the impossible possible: A case study of horizontal well drilling in Achimov formations of Urengoyskoe field (In Russ.), SPE-176508-MS, 2015, https://doi.org/10.2118/176508-MS
6. Ponomarev A.I., Marinin V.I., Safronov M.Yu. et al., Zadachi issledovaniya skvazhin i plastov achimovskikh otlozheniy Urengoyskogo NGKM na nachal'noy stadii osvoeniya (Problems of studying wells and formations of the Achimov deposits of the Urengoy oil and gas condensate field at the initial stage of development), Collected papers “Prioritetnye napravleniya razvitiya Urengoyskogo kompleksa” (Priority directions for the development of the Urengoy complex), Proceedings of Gazprom dobycha Urengoy, Moscow: Nedra Publ., 2013, pp. 123–132.
7. Ippolitov V.V., Sevodin N.M., Usynin A.F., Ensuring the stability of clay rocks in the drilling of deviated wells in the fields of the northern part of Western Siberia (In Russ.), Vestnik assotsiatsii burovykh podryadchikov, 2000, no. 2, pp. 13–18.
8. Bailey L., Denis J.H., Maitland G.C., Drilling fluids and wellbore stability – Current performance and future challenges, Chemicals in the Oil Industry, Royal Society of Chemistry, 1991, no. 12, pp. 53–70.9. Oort van E., Hale A.H., Mody K.F., Critical parameters in modelling the chemical aspects of borehole stability in shales and in designing improved water-based shale drilling fluids, Journal of petroleum technology, 1994, no. 28309, 14 p.
More or to buy article
In case of abnormally high formation pressures well-killing is a set of measures for the selection, preparation and injection of heavy well-killing fluids into the well. It should be noted that industrial fluids are expensive and do not always meet the requirements for well killing fluids for the conditions of Subsidiaries of Gazprom Neft Company. In order to search for high-quality process fluids with a density of up to 1600 and 1800 kg/m3 for killing production and injection wells at the fields of Gazprom Neft, laboratory studies were carried out. For extensive market research, inquiries were formed and sent to the base of manufacturers from 150 companies. 38 ready-mades well-killing fluids with density up to 1600 and 1800 kg/m3 were received from manufacturers. An analysis of the compliance with the technical documentation was passed by all 38 reagents. When carrying out physical and chemical studies of samples the main inconsistencies were identified in the following parameters: increased corrosiveness and incompatibility with formation waters at high formation temperature (85-114°C), high total suspended solids. Manufacturers are offered to improve the presented fluids to meet the requirements of the standard. Two compositions are recommended for further filtration studies. During series of filtration experiments, it was found that the lower porous medium permeability and the greater the hydrophilicity of the rock, the lower the coefficient of permeability recovery after well-killing. A twofold increase in the filtration rate makes it possible to increase the permeability recovery factor up to 2.5 times, which indicates a trouble-free development of the well after killing with the tested compositions with an increase in drawdown. Only one product was met all requirements for heavy well-killing fluids and were recommended for use at 3 Company’s fields. Due to the non-compliance of most of the products of the external market with the requirements of the Company, a decision was made to develop own formulations of heavy well-killing fluids.
1. Patent RU 2 731 965 C1, Heavy process fluid for killing wells, composition and method for preparation thereof, Inventors: Karpov A.A., Kunakova A.M., Kaybyshev R.R., Puchina G.R., Sergeeva N.A., Ragulin V.V.
2. Ryabokon’ S.A., Tekhnologicheskie zhidkosti dlya zakanchivaniya i remonta skvazhin (Process fluids for completion and repair of wells), Krasnodar: Publ. of NPO Burenie, 2009, 337 p.
3. Kunakova A.M., Duryagin V.N., The improvement of economic efficiency of the well control process by the implementation of new process liquids (In Russ.), PROneft’.Professional’no o nefti, 2016, no. 2. pp. 61–63.
4. Khakimov A.M., Makatrov A.K., Karavaev A.D. et al., Filtration testing of a new generation of surfactants of domestic and foreign production as additives to repair and process fluids during underground repairs and BHT of wells in hydrophilic reservoirs (In Russ.), Neftepromyslovoe delo, 2005, no. 12, pp. 48–53.5. Kunakova A.M., Karpov A.A., Makarova A.M., Development of new formulations of heavy well killing fluids with density of up to 1600 kg/m3 for the conditions of the fields of Gazprom Neft (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 12, pp. 34-38, https://doi.org/10.24887/0028-2448-2021-12-34-38
More or to buy article
Oil and gas facilities construction is usually affected by numerous risks which could alter initial plans of investors in terms of schedule and budget. At any stage of preparedness of such a project it is important to provide for the most reasonable cost estimate including contingency expenditures. The Russian methodology of cost estimation of oil and gas infrastructure facilities does not provide for evaluation of contingency capital expenditure (CAPEX) beyond local front-end engineering design (FEED) analogue which can lead to a significant risk of underestimation, especially at early stages of projects. International practice embraces examples of complex methodology of contingency assessment. However, as a rule, there are no generally accepted approaches to its assessment which would consider a technological complexity of a particular field facility.
The article considers methodology for estimation of the amount of CAPEX contingency using both Russian and international best practices could be used. The methodology is based on authors many years professional experience as well as on a significant database of the built facilities. The methodology involves an assessment on an object-by-object basis which considers a design (planning) stage of a particular facility as well as its technological complexity. In addition, the authors recommend to run a benchmarking exercise to determine a mid-industry regional comparative cost. The proposed approach makes it possible to quantify contingency cost funds needed to cover risks of early stages of projects development. At the same time the most risky projects with crucial impact on a final project cost are identified. A correct determination of contingency CAPEX will allow to reduce a risk of budget overrun and increase the probability of achieving the expected profitability of the project for the investor.
1. AACE International recommended practice no. 17R-97, Cost estimate classification system, 2003.
2. Cost estimating guide, US Department of Energy, DOE G 413.3-21A, DOE G 430.1-1
3. Metodika opredeleniya smetnoy stoimosti stroitel’stva, rekonstruktsii, kapital’nogo remonta, snosa ob»ektov kapital’nogo stroitel’stva, rabot po sokhraneniyu ob»ektov kul’turnogo naslediya (pamyatnikov istorii i kul’tury) narodov Rossiyskoy Federatsii na territorii Rossiyskoy Federatsii (Methodology for determining the estimated cost of construction, reconstruction, overhaul, demolition of capital construction facilities, work to preserve cultural heritage sites (monuments of history and culture) of the peoples of the Russian Federation on the territory of the Russian Federation), Put into effect by the Order of the Ministry of Construction, Housing and Communal Services of the Russian Federation No. 421/pr, 04.08.2020.4. Kokhanovskiy V.A., Sergeeva M.Kh., Komakhidze M.G., System complexity index (In Russ.), Vestnik DGTU = Vestnik of Don State Technical University, 2012, no. 4(65), pp. 22–26.
More or to buy article
Today, integrated model became one of the most effective operative tools for oil companies. Integrated model is the field simulation model that describes production chain and includes sequentially connected models of all elements such as models of a reservoir, well and surface infrastructure. The integrated model components are united by certain principles reflecting physical conditions of operation of all elements of the model. The integrated models are very important in strategical decision-making process during oil field development. In particular, the practice of applying the integrated models provides the most realistic forecasts in oil field development.
The article covers the experience in applying the integrated models in forecasting the production data for the high-viscous oil field and defining the reasons of failing the oil reservoir production potential. It is shown that production parameters estimated using reservoir models allows defining the production potential; however, lacking of a metering system for production and gathering, results in overstated estimates. In the same time the integrated model allows considering the constraints of all elements of the development system and provides for the most realistic forecasts. It is noted that under the existing production and transportation system, the producing potential of the considered field reduces by 1.6 times in fluid and by 1.7 times in oil. Regardless of new wells commissioning schedule, the limitation of the existing gathering and transportation system leads to the fact, that by the end of design period the considered options have similar values of cumulative oil uptakes. It is concluded that in order to realize the production potential of the field, it is necessary to modify the field gathering system.
1. Apasov R.T., Chameev I.L., Varavva A.I. et al., Integrated modeling: a tool to improve quality of design solutions in development of oil rims of multi-zone oil-gas-condensate fields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 12, pp. 46–49, DOI: 10.24887/0028-2448-2018-12-46-49
2. Ushmaev O.S., Apasov R.T., Chameev I.L. et al., Integrated modeling as a tool for evaluating the effects of well production rates and surface gathering system performance on development of oil rim (In Russ.), SPE-182007-MS, 2016, https://doi.org/10.2118/182007-MS
3. Povyshev K.I., Vershinin S.A., Vernikovskaya O.S., Integrated model "Reservoir – Well – Infrastructure" and its opportunities (In Russ.), PRONEFT''. Professional'no o nefti, 2016, no. 2, pp. 48–53.
4. Bogdanov E.V., Chameev I.L., Reshetnikov D.A. et al., Integrated modeling as a tool to increase the development efficiency of the multilayer oil-gas-condensate field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no 12, pp. 52–55, https://doi.org/10.24887/0028-2448-2019-12-52-55
5. Yanochkin S.V., Rychkov A.F., Integrated modeling. Experience in operating pilot projects (In Russ.), Neft'. Gaz. Novatsii, 2018, no. 12, pp. 29–30.
6. Rychkov A.F., Kadykov I.A., Postroenie integrirovannykh modeley mestorozhdeniy s vysokoproduktivnymi skvazhinami v usloviyakh malykh znacheniy depressiy na plast na primere Pamyatno-Sasovskogo mestorozhdeniya (Construction of integrated models of fields with highly productive wells in conditions of low values of drawdowns on the reservoir using the example of the Pamyatno-Sasovskoye field), Proceedings of Konferentsiya molodykh uchenykh i spetsialistov Golovnogo ofisa LUKOYL-Inzhiniring, 2018, Moscow, 2018, pp. 664–673.
7. Veliev M.M., Ivanov A.N., Akhmadeev A.G. et al., Calculation challenges of oil gathering and transportation systems of the high viscous oilfields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 10, pp. 108-111, DOI: https://doi.org/10.24887/0028-2448-2021-10-108-1118. Ivanov A.N., Veliev M.M., Veliev E.M. et al., Specifics of high-viscosity oil fields development under the low reservoir pressure conditions (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 8, pp. 50–52, https://doi.org/10.24887/ 0028-2448-2021-8-50-52
More or to buy article
At high-water-cut objects that are at a late stage of development, not only an increase in the water cut of well production is often observed, but also a simultaneous increase in the gas factor of oil to values exceeding those accepted in the calculation of reserves. The increase in the gas factor is due to the presence of gas dissolved in produced water. The volume of produced gas dissolved in water can often be comparable to or greater than the volume of gas dissolved in oil, and can significantly affect the discrepancy between the approved and actual gas production figures. Despite the existing scientific work in this direction, the possibility of forecasting and accounting for the volumes of such gas is not reflected in the regulatory documents. In this regard, an urgent task is to develop a methodology that allows to calculate the volumes of gas dissolved in water based on measured field data. When performing the task, it is important to justify the assumption about the possible impact of gas dissolved in produced water on the total gas production.
The article presents an algorithm for calculating the gas content of formation water to account for associated gas, based on the known dependences of the solubility of the main gas components (methane and nitrogen) with amendments that take into account the salinity of produced water, the solubility of methane in reservoir conditions, as well as phase equilibrium constants that depend on the composition and parameters of the phases. To test the developed algorithm, a series of calculations was carried out. Comparison of the results of calculations with the data of laboratory studies of mass transfer between gas-saturated oil and saline water and field measurements of the gas factor of production of high-water cut wells is carried out.
1. Gultyaeva N.A., Issledovanie prichin postupleniya gaza v dobyvayushchie neftyanye skvazhiny i razrabotki metodov identifikatsii ego istochnikov (Investigation of the causes of breakthrough of gas and development of methods for identifying its sources): thesis of candidate of technical science, Tyumen', 2015, 123 p.
2. Kordik K.E., Shkandratov V.V., Bortnikov A.E., Leont'ev S.A., About trends in the oil-gas ratio change in the process of exploitation of LUKOIL-West Siberia LLC fields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 8, pp. 54–57.
3. Gultyaeva N.A., Toshchev E.N., Mass exchange in the oil-gas-water and its effect on the production of associated gas (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 10, pp. 100-103.
4. Gultyaeva N.A., Krikunov V.V., Effect of gas reserves dissolved in formation water on the current distribution of the components volumes in oil wells production (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2012, no. 8, pp. 40-43.
5. Metodicheskie rekomendatsii po kompleksnomu izucheniyu mestorozhdeniy i podschetu zapasov poputnykh poleznykh iskopaemykh i komponentov (Guidelines for the integrated study of the deposits and associated reserves and components), Moscow: Publ. of SRC, 2007, 15 p.
6. Amerkhanov I.M., Reym G.A., Grebneva S.T., Kataeva M.R., Effect of injected water on oil-in-situ parameters (In Russ.), Neftepromyslovoe delo, 1976, no. 6, pp. 16-18.
7. Namiot A.Yu., Rastvorimost' gazov v vode (Solubility of gases in water), Moscow: Nedra Publ., 1976, 183 p.
8. Gul'tyaeva N.A., Shilov V.I., Fominykh O.V., Growth of the current GOR. Influence of gas dissolved in reservoir water on the total volume of gas produced with well production (In Russ.), Territoriya Neftegaz, 2013, no. 9, pp. 50–57.
9. Dodson C.B., Standing M.B., Pressure – Volume – temperature solubility relation for natural gas – water mixtures, Drilling and Products Practice, API, 1944.
10. Jones Park J., Petroleum production, Reinhold Publishing Corp., 1946, 293 p.11. Gulyat'eva N.A., Bobrov E.V., Influence of water-dissolved gas on development parameters of hydrocarbons deposits (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 4, pp. 52–54, https://doi.org/10.24887/0028-2448-2018-04-52-54
More or to buy article
Currently, a significant volumes of oil is extracted under complicated conditions, which include a significant slope of the well, as well as the rise of the reservoir medium from horizontal branches and high-viscosity oil. At the same time, a significant part of wells with high-viscosity oil, in order to increase the inflow, are drilled with a horizontal tap. Equipping most wells with sucker-rod pumps and the ability to adjust the length and number of strokes of the polished rod in a wide range allows to use these pumps in complicated conditions. The design features of the sucker-rod pumps such as their limited diameter and the coaxial arrangement of the valves with partial overlap of the valve body passage by the shut-off valve body significantly reduce these pumps throughput. Due to limited weight ball locking body does not always provide a tight overlap of the seat channel, especially when lifting high-viscosity oil and in inclined wells. So, the creation of rod pumps with full-flow valves those ensure the efficient operation of pumps in the environment of high-viscosity oil, as well as installed in inclined and horizontal wells is relevant. The article is considers the design and principle of operation of a rod pump with a movable cylinder and a controlled discharge valve, in which the valves are moved coaxially to the cylinder. In 2019-2021 the proposed sucker-rod pump has successfully passed pilot tests at the Vishnevo-Polyanskoye field of Oil and Gas Production Department Nurlatneft.
1. Persiyantsev M.N., Dobycha nefti v oslozhnennykh usloviyakh (Oil production in complicated conditions), Moscow: Nedra-Biznestsentr Publ., 2000, 653 p.
2. Patent RU 2567919 C1, Sucker rod pumping unit, Inventors: Ibragimov N.G., Zabbarov R.G., Zalyatov M.M., Sadykov A.F., Kozlov A.A., Kozlov D.A., Kalimullin D.M., Urazakov K.R.
3. Patent RU 2125184 C1, Oil-well sucker-rod pump unit, Inventors: Khaliullin F.Kh., Persiyantsev M.N.
4. Patent RU 2169290 C1, Oil-well sucker-rod pump, Inventors: Zakharov B.S., Bogomol'nyy E.I., Drachuk V.R.
5. Patent RU 2692588 C1, Pump, Inventors: Valitov M.Z., Nurgaliev R.Z., Bikbulatova G.I., Shulin V.S., Ganiev T.A.6. Patent RU 2708764 C1, Bottom-hole sucker-rod pump, Inventors: Valitov M.Z., Nurgaliev R.Z., Bikbulatova G.I.
More or to buy article
More or to buy article
The article presents a comprehensive approach, which permits to improve the accidents prediction system for tank farms. The comprehensive approach incorporates the following three stages: 1) numerical computer simulation of farm failure, evaluating forces of oil /oil products wave hydrodynamic effects on storage tank farm square enclosure walls; 2) calculation of storage tank farm square walls bearing capacity under extreme loads of oil /oil products’ waves; 3) computer simulation based on terrain relief with account of results obtained at the previous stages. The scientific novelty of the given recommendations is in synthesis of studied and time-and-experience proven methodological approaches, which have been confirmed by full-scale tests and results of investigations of happened accidents. Use of three methodologies in the approach permits to approximate with maximum likelihood ratio the simulated situations to possible results of crashes with considering a maximum quantity of factors that affect the consequences of possible accidents. The proposed approach could be incorporated in the management system of an enterprise, which provides services in transportation, storage or transfer of oil and oil products. The balanced system for predicting consequences of possible accidents, acceptance of preventive measures on avoidance of disastrous consequences will permit to decrease risks of unintended consequences for both the enterprise and third parties and economy as a whole. Uninterrupted operation of midstream operation facilities is one of the critical factors for ensuring energy security of Russia, a policy challenge, solution of which could be reached by various ways, including application of the comprehensive approach proposed by the authors. This approach is teamwork of interdisciplinary interaction of several science fields, which is successfully tested and endorsed for pipeline transportation facilities.
3. Gonchar A.E., Slepnev V.N., Bogach A.A., Assessment of inrush wave hydrodynamic effect and volume of overflow over walls of dyking (In Russ.), Nauka i tekhnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2021, V. 11(6), pp. 640–651, https://doi.org/10.28999/2541-9595-2021-11-6-640-651.
4. Slepnev V.N., Maksimenko A.F., The basic principles of building a quality management system for prevention, localization and liquidation of effects of accidents at pipeline transport facilities (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2018, V. 8, no. 4, pp. 456–468, https://doi.org/10.28999/2541-9595-2018-8-4-456-467
5. Slepnev V.N., Maksimenko A.F., Organizing the quality management system for the processes of prevention, localization and elimination of accidents at pipeline transport facilities (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 2, pp. 106–111, https://doi.org/10.24887/0028-2448-2019-2-106-111
6. Polovkov S.A. et al., Assessment of the risk of damage to pipelines located in the Arctic zone of the Russian Federation. Modeling of a spill and determination of the possible volume of oil taking surface topography into consideration (In Russ.), Territoriya Neftegaz, 2016, no. 12, pp. 88–93.
7. Polovkov S.A., Shestakov R.Yu., Aysmatullin I.R., Slepnev V.N., System conception in the development of measures on prevention and localization of accident consequences on oil pipelines in the arctic zone of Russian Federation (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2017, no. 1(28), pp. 20–29.
8. Polovkov S.A. et al., Development of additional protecting constructions from oil spills based on three-dimensional digital modeling (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2018, V. 8, no. 2, pp. 197–205, https://doi.org/10.28999/2541-9595-2018-8-2-197-205
9. Aysmatullin I.R. et al., A systematic approach to protecting the Arctic from the effects of accidents on trunk pipelines (In Russ.), Neftegaz.Ru, 2018, no. 5, pp. 66–72.10. Gitis V.A. et al., Mathematical modeling of surface runoff and pollution transport (In Russ.), Informatsionnye protsessy, 2007, V. 7, no. 2, pp. 168–182.
More or to buy article
Reduction of carbon footprint is a world community key goal. Modern corporations for motor-cars and their components manufacture are working hard on carbon footprint reduction by developing more effective and powerful combustion engines running on diesel fuel. Growth of requirements concerns both combustion engines and quality of fuel for these engines. Minute particles of mechanical impurities available in the diesel fuel in suspension could result in seizure of moving members of high-pressure pumps and combustion engines; in this connection qualitative purification of diesel fuel is required in case of its contamination. Filtration is the main method of diesel fuel purification against mechanical impurities. Filtering elements with filtration degree of 1 µm are required to remove minute particles of mechanical impurities. In case of strong contamination and high diesel fuel amounts, filtering elements are quickly clogged that causes their frequent replacement and operational costs increase. In this connection, searching for alternate diesel fuel purification methods is topical issue.
The article presents results of laboratory and field tests of various diesel fuel purification methods, which permit to evaluate their effectiveness in removing minute suspended particles from the diesel fuel. The authors have found that effectiveness of filtration with using various filtering elements, including gauze, cellulose and polymeric ones, diminishes with time. In addition, the performed studies demonstrate that there is a number of alternate methods for diesel fuel purification. Purification effectiveness of these methods is comparable with that of filtration, and their effectiveness is not decrease with time. It could be concluded from the obtained data that several techniques shall be considered when selecting a purification method, including their possible combinations.
1. Kucherov V.N., Leont'ev L.B., Leont'ev A.L., Influence of wear of high-pressure fuel pump plunger pairs on the performance of marine diesel engines (In Russ.), Vestnik Inzhenernoy shkoly DVFU = FEFU: School of Engineering Bulletin, 2021, no. 1(46), pp. 49–62, http://www.dx.doi.org/10.24866/2227-6858/2021-1-5
2. Timofeev F.V., Development of a quality saving system for oil products subject to pipeline transportation (In Russ.), Vesti gazovoy nauki, 2020, no. 2(44), pp. 73–78.3. Kupkenov R.R. et al., Oil products purity monitoring in transportation through the main pipelines (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2019, V. 9, no. 3, pp. 342–352, https://doi.org/10.28999/2541-9595-2019-9-3-342-352
More or to buy article
The driver of the transition to socio-economic development, taking into account environmental constraints, is the satisfaction of people needs for cheap, reliable, safe and environmentally friendly energy sources. In the context of the need to increase the level of decarbonization of the world economies, the expansion of the use of alternative energy is becoming the main climate agenda and requires transformations of the global energy sector. The article substantiates the necessity and identifies the factors of the development of the renewable energy sector, characterized by the presence of stimulating trends and increasing demand from economic systems of various levels. The study is based on specific data reflecting trends in the development of global energy, for the processing of which comparative analysis methods were used. The conducted studies have revealed a number of factors that ensure a large-scale increase in the alternative energy sector, which include: achieving comparability of prices and indicators of its efficiency in comparison with traditional sources, ensuring a balanced load on the power grid, as well as the large-scale introduction of innovative technologies. In addition, there was an increase in the interest of a wide range of consumers in the implementation of the processes of decarbonization of the economy, price reduction and uninterrupted supply of "clean" electricity, providing the renewable energy sector with further expansion within the framework of the structure of the world energy balance. The renewable energy sector has practical significance and implications for society, taking into account the development of civilization within the human-centered trajectory and the need to solve socio-ecological and economic problems facing it, and can be used in the process of developing and implementing a sustainable development strategy in the "green" trend.
1. Sustainable development goals, URL: https://www.undp.org/content/
2. Dolya vozobnovlyaemykh istochnikov energii v proizvodstve elektroenergii (Share of renewable energy sources in electricity generation), URL: https://yearbook.enerdata.ru/renewables/renewable-in-electricity-production-share.html
3. Petrenko L.D., Green trend in global energy development: Tendencies and opportunities, International Journal of Energy Economics and Policy, 2021, V. 11(5), pp. 1-7, https://doi.org/10.32479/ijeep.11094
4. Zakhozhiy K.A., Renewable energy sources (In Russ.), Colloquium journal, 2020, no. 28(80), pp. 57–58.
5. Installed capacity trends, URL: https://www.irena.org
6. Gorbacheva N.V., Renewable energy governance: global experience and Siberia (In Russ.), Voprosy gosudarstvennogo i munitsipal'nogo upravleniya, 2020, no. 2, pp. 85–113.
7. Global Renewables Outlook: Energy transformation 2050, URL: https://www.irena.org/publications/2020/Apr/Global-Renewables-Outlook-2020
8. Dolya vetrovoy i solnechnoy energii v proizvodstve elektroenergii (Share of wind and solar energy in electricity generation), URL: https://yearbook.enerdata.ru/renewables/wind-solar-share-electricity-production.html
9. Cetkovic S., Buzogany A., Between markets, politics and path-dependence: Explaining the growth of solar and wind power in six Central and Eastern European countries, Energy policy, 2020, V. 139, pp. 111325, https://doi.org/10.1016/j.enpol.2020.111325
10. Lazard’s levelized cost of energy analysis – version 15.0, URL: https://www.lazard.com/media/451905/lazards-levelized-cost-of-energy-version-150-vf.pdf
11. Ustoychivoe razvitie dlya luchshego budushchego (Sustainability for a better future), URL: https://www.enelrussia.ru/ru/stories/a201612-smart-homes-smart-cities.html
12. “Enel Rossiya” izbavilas' ot ugol'nykh aktivov i stroit vetryaki (Enel Russia got rid of coal assets and builds wind turbines), URL: https://journal.tinkoff.ru/news/enel-strategy-2022/
13. Renewable Capacity Statistics 2022, URL: https://www.irena.org/publications/ 2022/Apr/Renewable-Capacity-Statistics-2022
14. Al-Ashouri A. et al., Monolithic perovskite/silicon tandem solar cell with >29% efficiency by enhanced hole extraction, Science, 2020, V. 370, no. 6522, pp. 1300-1309, https://doi.org/10.1126/science.abd401615. Hannesson R., How much do European households pay for green energy, Energy policy, 2019, V. 131, pp. 235-239, https://doi.org/10.1016/j.enpol.2019.05.010
More or to buy article