The overall industry trends force companies into toughening their requirements to accuracy and validity of estimations at the stage of conceptual design. As a rule, the estimation involves application of aggregate per unit indicators which do not achieve the required result. A lack of scalable estimations, technical flexibility, as well as high estimation sensitivity to the involved similar facilities demands a review of the standard approaches and application of combined solutions. As an alternative to aggregate per unit indicators the authors propose a comprehensive application of cost data bases of modular comparable facilities (for on-site facilities), and parametric cost models (for linear objects). Due to standardized classification and ability to determine detailed per unit indicators a data base is flexible and adapted to cost modelling for new facilities. Cost models allow to numerically express dependence between the key factors affecting the costs. 

This paper gives criteria for developing successful comprehensive expenditure estimation models, tools available to improve the estimation accuracy, and describes a practical case where the proposed method was used. The analysis of differences between initial estimates on the basis of aggregate per unit indicators and results of estimation where the proposed method was applied that the authors conducted allowed, on the basis of available actual construction cost figures, to conclude that a comprehensive approach is efficient. Efficiency was assessed through not only enhanced accuracy, but also the speed of capital expenditure estimation. Thus, an integrated technical and economic upstream CAPEX modelling at a pre-FEED stage allows: 1) to adjust the estimation to the peculiarities of each particular project; 2) to analyze the impact of the estimation and cost parameters for certain facilities at the level of technological blocks; 3) to increase the accuracy of the project estimation and benchmarking, as well as reduce the investment decision risks even with no full input data for technical characteristics of construction facility.

References

1. Bozieva I.A., Zinnatullin D.F., Aspects of corporate information system development to generate the costs of construction facilities and oil and gas fields infrastructure development (In Russ.), Neftyanoe khozyaistvo = Oil Industry, 2016, no. 2, pp. 114–117.

2.  Chizhikov S.V., Dubovitskaya E.A., Pashchenko A.D., Problems and proposed solutions for oil and gas projects cost estimation in Russia (In Russ.), Neftyanoe khozyaistvo = Oil Industry, 2013, no. 9, pp. 92–95.

3. Chizhikov S.V., Dubovitskaya E.A., Tkachenko M.A., Costs modeling: Support point in a changing world (In Russ.), Neftyanoe khozyaistvo = Oil Industry, 2017, no. 10, pp. 64–68, http://dx.doi.org/10.24887/0028-2448-2017-10-64-68.

4. Atnagulov A.R., Rakhmangulov R.D., Vinogradov P.V., Kireev G.A., Gizbrekht D.Yu., Developing CAPEX database for oil field surface facilities construction at Bashneft PJSOC (In Russ.), Neftyanoe khozyaistvo = Oil Industry, 2015, no.8, pp. 98–101.

5. Panov R.A., Mozhchil' A.F., Dmitriev D.E. et al., Digital conceptual engineering: automatization of facilities allocation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 12, pp. 72–75, http://dx.doi.org/10.24887/0028-2448-2018-12-72-75.

6. Rustamov I.F., Sobolev A.O., Sozonenko G.V. et al., Developing software prototype for well cost estimation and its ability (In Russ.), Neftyanoe khozyaistvo = Oil Industry, 2016, no.  12. – S. 24–27.

7. Khasanov M.M., Sugaipov D.A., Zhagrin A.V. et al., Improvement of CAPEX estimation accuracy during early project stages (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 12, pp. 22–27.

8. Khasanov M.M., Sugaipov D.A., Maksimov Yu.V. et al., Cost engineering in Gazprom Neft PJSC: current situation and future development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 12, pp. 30–33.

9. Chizhikov S.V., Dubovitskaya E.A., A new approach to the assessment and management of oil and gas projects cost (in Russ.), Neftyanoe khozyaistvo = Oil Industry, 2012, no. 9, pp. 98–101.

The influence of tectonics evolution of passive margin East-European platform (EEP) (within Bashkortostan) to form oil and gas deposits are discussed in the article. Studied territory during more 2.5 billion years was developing from primordial boulder-block framework Archean-Lower Proterozoic foundation to contemporary typical platform beds sedimentary rocks on the given crystal bed. Erode relief of crystalline basement, which constitutes sag along latitude, fill up with consolidative sediments and dipping step by step to East – to Pre-Urals foremost depression. Sedimentary cover contains Rifenian-Vendian and over Paleozoic sediments. The average thickness of Riphean-Vendian sedimentary cover makes up 7.0 km and its total thickness more than Paleozoic in 4.5 times. The average thickness of Paleozoic sediments is 3.0 km. By seismic and aeromagnetic data there were ascertain abatement of dislocating tectonics from the crystalline basement to Paleozoic deflections, which breaks be considered as a rarity. All oil and gas fields (more than 210) were ascertained in Paleozoic deflections, which contain seven Oil-Gas complexes. Its two terrigenous include 88% of total initial hydrocarbon reserves. The rentable masses of hydrocarbon in Riphean-Vendian sediments were not exposed because of fluid-cover absence up to the present time. During a long time, geological conception about classical monocline tectonic pattern of East margin EEP were corroborated by open oil and gas fields in plikative large-scale gross output structures Tuymasynian type. But at 1960s “small grabens”- regionally consedimentary grabens in terrigenous Devonian and postsedimentary grabens in Vendian-Paleozoic geological section are discovered. Than the echelon of consedimentary grabens, the horst-like zones – narrow semi-regional structures of conciseness are determined. The role of all list dislocates is containing in setting up absolutely new zones oil-gas bearing. Ones controlled oil fields with total reserves nearly a quarter of total initial hydrocarbon reserves of the Bashkir region. Detail analysis permits in any way examine well-known geological facts. The ambiguous function of regional and semi-regional dislocates were ascertained. On initial stage, they serve as conductor for vertical migration hydrocarbons and on the late-stage its function transformation to the (tectonic) screen with form oil deposits. Many oil fields settle down in dislocating zones. The efforts of press from the Urals were favourable this prose.

References

1. Trofimuk A.A., Neftenosnost' paleozoya Bashkirii (Oil content of the Paleozoic of Bashkortostan), Moscow: Gostoptekhizdat Publ., 1950, 248 p.

2. Trofimuk A.A., Usloviya obrazovaniya mestorozhdeniy Uralo-Volzhskoy neftenosnoy oblasti (Conditions for the formation of deposits in the Ural-Volga oil-bearing region), Part 1, Moscow: Publ. of Academy of Sciences of the USSR, 1955, 26 p.

3. Rozanov L.N., Istoriya formirovaniya tektonicheskikh struktur Bashkirii i prilegayushchikh oblastey (History of formation of tectonic structures of Bashkiria and adjoining areas), Ufa: Publ. of UfNII, 1957, 207 p.

4 Ovanesov G.P., Formirovanie zalezhey nefti i gaza v Bashkirii, ikh klassifikatsiya i metody poiskov (Formation of oil and gas deposits in Bashkiria, its classification and search methods), Moscow: Gostoptekhizdat Publ., 1962, 296 p.

5. Egorova N.P., Khalimov E.M., Ozolin B.V. et al., Zakonomernosti razmeshcheniya i usloviya formirovaniya zalezhey nefti i gaza Volgo-Ural'skoy oblasti (Regularities of location and conditions for the formation of oil and gas deposits in the Volga-Urals region), Part 4. Bashkirskaya ASSR (The Bashkir ASSR), Moscow: Nedra Publ., 1976, 240 p.

6. Lozin E.V., Geologiya i neftenosnost' Bashkortostana (Geology and oil content of Bashkortostan), Ufa: Publ. of BashNIPIneft', 2015, 704 p.

7. Lozin E.V., Anomal'no vysokoe plastovoe davlenie v neftyanykh zalezhakh v zonakh grabenoobraznykh progibov: svyaz' s mekhanizmom obrazovaniya zalezhey (Abnormally high reservoir pressure in oil reservoirs in zones of graben-like troughs: connection with the mechanism of reservoir formation), Proceedings of BashNIPIneft', 1992, V. 85, pp. 19–25.

8. Khat'yanov F.I., Paleorifty i transformnye mikrorazlomy na vostoke Russkoy plity (In Russ.), Metallogeniya i novaya global'naya tektonika, 1973, pp. 130-132.

9. Khat'yanov F.I., On the tectonic nature of buried Devonian micro-grabbers and the prospects for the search for oil-bearing structures in the southeast of the Russian platform (In Russ.), Geologiya nefti i gaza, 1971, no. 7, pp. 41–46.

10. Lozin E.V., Dragunskiy A.K., Age of graben-like troughs of Bashkiria (In Russ.), Izvestiya AN SSSR. Seriya geologicheskaya, 1988, no. 8, pp. 122–129.

11. Lozin E.V., On the mechanism of formation of sedimentary graben-like troughs in the east of the East European platform (In Russ.), Geologiya nefti i gaza, 1994, no. 2, pp. 16-17.

12. Lozin E.V., Racheva L.M., Specification of structure for post-sedimentary graben-like deflections in the platform using relevant seismic data (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 9, pp. 8–11.

13. Trofimov V.A., Korchagin V.I., Oil supply channels: spatial position, detection methods and methods of their activation (In Russ.), Georesursy, 2002, no. 31(9), pp. 18–23.

14. Utoplennikov V.K., Ogarinov I.S., Yarullin K.S., Controversial ideas about the structure and prospects of oil-bearing capacity of the Cis-Ural trough (In Russ.), Geologiya nefti i gaza, 1987, no. 3, pp. 53–55.

The results of original scientific investigation for the study of present-day “fracture” ways of the hydrocarbon migration within the Russian sector of the North-Western part of the Caspian sea are considered. The space connections between in the rocks internal structure (the presence of pervious micro-fracturing), in the oil-saturating of rocks, in the presence and quantitative content of rare gases (helium, hydrogen) in the composition of the reservoir fluids selected from search-prospect wells is established at the point level. The criteria for forecasting of the fault-fracture systems of young age (pervious for fluids) and of degree of activity within their present-day fluid-migration processes were the presence or absence of helium and hydrogen (having deep origin and specific physicochemical features of paramount importance for the present study) in the composition of formation fluids (oil, released gas, free gas). The differently oriented fault-fracture systems of young age within the North-Western part of the Caspian Sea are differentiated in the direction and activity degree of present-day migration processes within their limits. So, within the vertical and inclined fault systems (especially in the Southern and Eastern parts of the Russian sector of the North-West Caspian), present-day fluid-migration processes are developing very quickly. The fluids from wells crossing these faults contain helium and hydrogen throughout the section. But, within the horizontal multi-tiered fault-fracture system, regionally developed in the Middle Jurassic-Lower Cretaceous section, present-day fluid-migration processes are developing not so quickly. The helium is present in formation fluids from these fractured intervals, but the hydrogen is absent. The possibility of the forecast of the present-day hydrocarbon migration “fracture” ways on the point (well) level even at the oil and gas search-prospect stage is given.

References

1. Kas'yanova N.A., New concept for the structure and formation of the North Caspian Rakushechno-Shirotnyi swell (In Russ.), Geologiya nefti i gaza = The journal Oil and Gas Geology, 2017, no. 1, pp. 24–31.

2. Kas'yanova N.A., The role of young fracturing in the formation and spatial distribution of hydrocarbon deposits in the North-Western Caspian Sea (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 5, pp. 36–39.

3. Kas'yanova N.A., Sovremennaya prostranstvenno-vremennaya migratsiya tektonicheskoy napryazhennosti v zemnoy kore Kavkaza i Predkavkaz'ya (Modern spatio-temporal migration of tectonic tension in the earth's crust of the Caucasus and Ciscaucasia), In: Obshchaya i regional'naya geologiya, geologiya morey i okeanov, geologicheskoe kartirovanie (General and regional geology, geology of seas and oceans, geological mapping), Moscow: Geoinformmark Publ., 1994, no. 3, pp. 1–15.

4. Kas'yanova N.A., Abramova M.E., Gayrabekov I.G., Horizontal deformations of the Eastern Caucasus based on high-precision geodetic measurements (In Russ.), Geotektonika, 1995, no. 2, pp. 86–90.

The paper presents the results of the three-dimensional basin and petroleum systems modeling in the Vilyui hemisyneclise located in the Republic of Sakha (Yakutia). The modeling identifies maturity history of organic matter, kitchen areas, and quantitive evaluation of generation power of the source rocks. According to the research, the Permian source rock enriched in terrestrial organic matter contributes to the Upper Paleozoic and Mesozoic deposits in the Vilyui hemisyneclise. Hydrocarbon trapping is expected to be in the Lower Cretaceous. The structures, elements of the Upper Permian-Mesozoic petroleum system, and generation and migration processes had already been in place in the study area. The critical moment of the Permian petroleum system is supposed to be at the late Lopingian (253 Ma). The Permian source rock top is found to be in the oil and gas windows at the present time. The Linden depression corresponds to the major kitchen area. The generation balance and remaining potential of the Permian source rock are 4 trillion tons and 1 trillion tons of hydrocarbons (hydrocarbon equivalent), respectively. Generation power of the Kuonam formation enriched in marine organic matter is not exhausted in the elevated northern and southern parts, clay seals becoming sandy and pinching out around the edge of the Vilyui hemisyneclise. The hydrocarbon deposits originated from the Jurassic claystone and coal rocks is assumed to be in the Linden depression in the presence of appropriate environment for the hydrocarbon accumulation.

Acknowledgement. The reported study was funded by RFBR, project number 19-35-90039.

 References

1. Kontorovich A.E. et al., The current state and challenges of the replacement of the mineral resource base of hydrocarbons in Eastern Siberia and the Republic of Sakha (Yakutia) (In Russ.), Mineral'nye resursy Rossii, 2014, no. 6, pp. 15–27.

2. Kontorovich A.E., Leno-Vilyuyskiy basseyn (Lena-Vilyui basin), Neftegazonosnye basseyny i regiony Sibiri (Oil and gas basins and regions of Siberia), Novosibirsk: Publ. of SB of RAS, 1994, V. 4, 107 p.

3. Gubin I.A., Refinement of the structure of the Vilyuy hemisyneclise based on the results of reinterpretation of seismic exploration (In Russ.), Geologiya i mineral'no-syr'evye resursy Sibiri, 2020, no. 4, pp. 40–52.

4. Sitnikov V.S. et al., Newest forecast and development updating of Vilyuiskaya syncline petroleum objects (In Russ.) Neftegazovaya geologiya. Teoriya i praktika, 2017, V. 12, no. 1, URL: http://www.ngtp.ru/rub/6/9_2017.pdf

5. Polyanskiy O.P. et al., The rift origin of the Vilyui basin (East Siberia), from reconstructions of sedimentation and mechanical mathematical modeling (In Russ.), Geologiya i geofizika, 2013, V. 54, no. 2, pp. 163–183.

6. Tomilova N.N., Yurova M.P., Nizhnetriasovye vulkanogennye lovushki gaza Yakutii: genezis, stroenie kollektora, osobennosti osvoeniya (Lower Triassic volcanogenic gas traps in Yakutia: genesis, reservoir structure, development features), Collected papers “Problemy resursnogo obespecheniya gazodobyvayushchikh rayonov Rossii do 2030” (Problems of resource provision for gas-producing regions of Russia until 2030), Moscow: Publ. of Gazprom VNIIGAZ, 2012, pp. 208–216.

7. Kontorovich A.E. et al., Neftegazogeologicheskoe rayonirovanie Sibirskoy platformy (utochnennaya versiya) (Oil and gas-geological zoning of the Siberian platform (updated version)), Collected papers “Nedropol'zovanie. Gornoe delo. Napravleniya i tekhnologii poiska, razvedki i razrabotki mestorozhdeniy poleznykh iskopaemykh. Geoekologiya” (Subsoil use. Mining. Directions and technologies for the search, exploration and development of mineral deposits. Geoecology), Proceedings of International Scientific Conference “Interekspo GEO-Sibir'-2017”, Novosibirsk, 17–21 April 2017, Part 1, Novosibirsk: Publ. of SGUGiT, 2017, pp. 57–64.

8. Moskvin A.G., Leno-Vilyuyskaya gazoneftenosnaya provintsiya (Lena-Vilyui oil and gas province): In “Bol'shaya rossiyskaya entsiklopediya” (Big Russian Encyclopedia), 2004, URL: https://bigenc.ru/geology/text/2139848

9. Kashirtsev V.A. et al., Geokhimiya neftey vostoka Sibirskoy platformy (Geochemistry of oils from the east of the Siberian platform), Yakutsk: Publ. of YSC SB RAS, 2009, 180 p.

10. Bogorodskaya L.I., Kontorovich A.E., Larichev A.I., Kerogen: metody izucheniya, geokhimicheskaya interpretatsiya (Kerogen: methods of study, geochemical interpretation), Novosibirsk: Publ. of SB of RAS, 2005, 254 p.

11. Kontorovich A.E. et al., Transformation of terrestrial organic matter during mesocatagenesis and apocatagenesis (In Russ.), Geologiya i geofizika, 2020, V. 61, no. 8, pp. 1093–1108.

12. PetroMod petroleum systems modeling, Schlumberger Information Solutions, 2011, 256 p.

13. Kosmacheva A.Yu., Fedorovich M.O., Revising source rocks of the central part of loglor structure according to one-dimensional petroleum system modeling (Andylakh field, the Republic of Sakha (Yakutia)) (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2021, V. 16, no. 1, URL: http://www.ngtp.ru/rub/2021/7_2021.html

14. Fedorovich M.O. et al., One-dimensional petroleum system modeling (basin modeling) in a well section of Tolonskoye field in the Republic of Sakha (Yakutia) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 5, pp. 31–35.

15. Olli I.A., Organicheskoe veshchestvo i bituminoznost' osadochnykh otlozheniy Sibiri (Organic matter and bituminous content of sedimentary deposits in Siberia), Moscow: Nauka Publ., 1975, 135 p.

Bazhenov formation is one of the most discussable subject of geological studies in the Western Siberia basin. However, recent high-tech core analysis and new methodological technique of knowledge integration allowed to distinguish this Jurassic organic-rich source-rock formation as a new stratigraphic-geochemical unit. This type of sours rocks has 2 basic features: organic matter content less then 2.5% and only marine environment of deposition. The main idea of such classification is the attempt to determine source rock by reservoir type. The organic-rich source rock is triadic. It is mother rock, reservoir rock and seal in the same time and is independent of lithology. The Jurassic organic-rich source-rock formation in the Western Siberia can be classified as a regional reservoir also.

The article describes the methods and techniques for the geological investigation and algorithm of knowledge integration based on the studies of the Western Siberia Jurassic organic-rich source rock. The initial element of the study of the Bazhenov formation is well section. The complex of geochemical, lithological and petrophysical laboratory studies is applied equally to the productive and non-productive intervals of the section. Well sections of The Bazhenov formations are stratified and correlated based on lithology, paleontology, and well logging data. The paleogeomorphological profiles describe the lateral and vertical variability of the Bazhenov layers in valleys, on arches and slopes of paleostructures. The area of distribution of siliceous, phosphate, and carbonate reservoirs is controlled by the sedimentation conditions of each of them, as well as by the degree of maturity, which determines the formation of secondary pores, caverns and cracks. At the low stage of catagenesis siliceous, phosphate, and carbonate layers have low reservoir properties, at the late stages of catagenesis all layers transformed to good reservoirs. 

The proposed algorithm of knowledge integration can be applied to other organic-rich source-rock formations with low thickness, complex lithofacies zoning and pore space structure.

References

1. Brekhuntsov A.M., Nesterov I.I., Oil of bituminous-clay, clint-clay and carbonate-clint-clay rocks (In Russ.), Vestnik TsKR Rosnedra, 2010, no. 6, pp. 3–16.

2. Technically recoverable shale oil and shale gas resources: An assessment of 137 shale formations in 41 countries outside the United States, URL: https://www.eia.gov/analysis/studies/worldshalegas/pdf/overview.pdf

3. Curtis M.E., Cardott B.J., Sondergeld C.H., Raia Ch.S., Development of organic porosity in the Woodford Shale with increasing thermal maturity, International Journal of Coal Geology, 2012, V. 103, pp. 26–31.     

4. Kalmykov G.A., Balushkina N.S., Model' neftenasyshchennosti porovogo prostranstva porod bazhenovskoy svity Zapadnoy Sibiri i ee ispol'zovanie dlya otsenki resursnogo potentsiala (Model of oil saturation of the pore space of rocks of the Bazhenov formation in Western Siberia and its use for assessing the resource potential), Moscow: GEOS Publ., 2017, 246 p.

5. Braduchan Yu.V., Gurari F.G., Zakharov V.A. et al., Bazhenovskiy gorizont Zapadnoy Sibiri (Bazhenov horizon of Western Siberia), Moscow: Nauka Publ., 1986, 216 p.

6. Karta razmeshcheniya skopleniy nefti v bazhenovskoy svite na territorii Zapadno-Sibirskoy NGP (Map of the location of oil accumulations in the Bazhenov formation on the territory of the West Siberian oil and gas complex), Moscow: Publ. of Ministry of Energy of the Russian Federation, Russian Academy of Sciences, IGiRGI.

7. Kondrat'ev I.K., Ryzhkov V.I., Bondarenko M.T. et al., Vozmozhnost' prognozirovaniya kollektorov bazhenovskoy svity sposobami seysmicheskoy inversii (Possibility of forecasting reservoirs of the Bazhenov formation by seismic inversion methods), EAGE Tumen, Expanded Abstracts, 2013.

8. Kislukhin I.V., Osobennosti geologicheskogo stroeniya i neftegazonosnost' yursko-neokomskikh otlozheniy poluostrova Yamal (Features of the geological structure and oil and gas content of the Jurassic-Neocomian deposits of the Yamal Peninsula): edited by Nesterov I.I., Tyumen: Publ. of TyumSPTU, 2012, 116 p.

9. Nezhdanov A.A., Kulagina S.F., Kornev V.A., Khafizov F.I., Anomalous sections of Bazhenov suite: a view throughfifty years after discovery (In Russ.), Izvestiya vysshikh uchebnykh zavedeniy. Neft' i gaz, 2017, no. 6, pp. 34–42, https://doi.org/10.31660/0445-0108-2017-6-34-42-

10. Ryzhkov V.I. Dan'ko D.A., The study of the secondary transformed radiolarians layer in the Bazhenov formation using seismic data (In Russ.), Geofizika, 2016, no. 3, pp. 2–11.

11. Khamidullin R.A. et al., The reservoir properties of the rocks of the bazhenovskaya formation (In Russ.), Vestnik Moskovskogo Universiteta. Ser. 4. Geologiya = Moscow University Geology Bulletin, 2013, no. 5, pp. 57 – 64.

12.  Baturin Yu.E., Justification of abolition necessity of the mining operations tax under the development of Bazhenovskiy deposits (In Russ.), Vestnik TsKR Rosnedra, 2010, no. 6, pp. 17–21.

13. Volyanskaya V.V., Methodological aspects of the different-level tectonic modeling (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 5, pp. 14-17.

14. Dmitrievskiy A.N., Izbrannye trudy (Selected works), Part 1. Sistemnyy podkhod v geologii: teoreticheskie i prikladnye aspekty (Systems approach in geology: theoretical and applied aspects), Moscow: Nauka Publ., 2008, 454 p.

15. Vasil'ev A.L., Pichkur E.B., Mikhutkin A.A. et al., The study of pore space morphology in kerogen from Bazhenov formation (In Russ.), Neftyanoe khozyaystvo = Oil Industry,  2015, no. 10, pp. 28–31.

In today's world, with the increasing cost of exploration, a more optimal and practical approach to its implementation is required. The "Sweet Areas" methodology for resource assessment, risk assessment and exploration programm is based on prioritizing promising objects by their degree of study and perspective. As part of the work at Rosneft Oil Company, using this technique, it was possible to form a pool of low-risk priority objects for inclusion in the exploration program. The author's approach makes it possible not only to rank promising objects by the number of resources and the degree of riskiness, but also to form an optimal exploration program aimed at quickly clarifying the properties and prospects of a new potential trap. Within the framework of the concept of "Sweet Areas," prospective objects are combined into 5 groups, separate in degree of study: SA1 - resources in the reserves circuits C1 (reserves prepared for production); SA2 - resources in the reserves circuits C2 (reserves prepared for production but requiring transfer to C1); SA3 - resources studied by seismic 3D, but not explored by drilling; SA4 - resources barred according to the seismic 2D (need 3D data) to clarify the geometry of objects; SA5 - resources conditionally localized based on regional trends and dependencies. One example is promising objects associated with foundation projections at the Srednebotuobinskoye oil-gas-condensate field. The analysis of seismic data materials, as well as the assessment of resources and risks using the Sweet Areas methodology, made it possible to determine the first promising search object within the Srednebotuobinskoye field on the territory of the Kurung area.

References

1. Mel'nikov R.S., Dan'ko E.A., Tverdokhlebov D.N., Kleshnin A.B., Interpretative quality control of seismic processing in seismic conditions of Eastern Siberia region (In Russ.), Nedropol'zovanie XXI vek, 2019, no. 6, pp. 34–41

2. ayduk A.V., Al'mendinger O.A., Formation conditions and criteria for prediction of areas of improved reservoir properties ancient Vendian-Cambrian reservoirs (for example, Danilovskiy license area (East Siberia)) (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “NK “Rosneft'”, 2013, no. 1, pp. 10-13.

3. Gordeev Ya.I., Gayduk A.V., Mityukov A.V., Filichev A.A., The results of exploration of Rosneft’s license areas in the Irkutsk region for 10 years (In Russ.), Neftyanoe khozyaystvo = Oil industry, 2016, no. 11, pp. 15–17.

4. Gayduk A.V., Kashirina E.G., Red'kin N.A. et al., Regularities of development of perspective objects in carbonate Vendian-Cambrian sedimentary cover of the southern Siberian platform (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “NK “Rosneft'”, 2016, no. 3, pp. 28–31.

5. Gayduk A.V., Fomin A.E., Tverdokhlebov D.N. et al., Oil and gas prospective facilities identification in the subsalt carbonate complex of Nepa-Botuoba anteclise as a result of historical 2D seismic data reprocessing and reinterpretation (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “NK “Rosneft'”, 2016, no. 3, pp. 44–48.

The identification of "bright spot" anomalies on seismic sections is a traditional qualitative express-method for predicting the gas saturation of hydrocarbon traps. But it is known, that such anomalies are not always coincide with gas fields. Experience shows that, in addition to fluid saturation, they can be caused by lithological heterogeneities. So in doubtful cases it is necessary to use more "heavy" quantitative methods of seismic data interpreting for «bright spot» anomalies analysis. One of such methods is simultaneous inversion, since it transforms the seismic amplitudes of prestack data into elastic parameters. At first, such transformation makes it possible to predict the distribution of lithotypes in sedimentary basins.

This article deals with the experience gained from the analysis of "bright spot" dynamic anomalies in one of the small petroleum basins. There was structural gas field in the area, marked on seismic sections by a dynamic “bright spot” anomaly and a structural trap with a similar dynamic anomaly. Since unsuccessful wells had already been drilled in the area adjacent to the trap, the interpreters were tasked to find out the nature of the indicated dynamic anomaly. As a result of simultaneous inversion of the specially processed prestack data, it was determined that for the gas field a dynamic “bright spot” anomaly is caused by an abnormally low acoustic impedance of the upper section of the gas-bearing reservoir. For the structural trap, a similar anomaly is due to the lithological heterogeneities of the anhydrite seal overlying the reservoir. As a result of the investigation it was concluded that the gas potential of the identified structural trap is not essential, probably due to its small size and ineffective hydrocarbon migration.

References

1. Voskresenskiy Yu.N., Izuchenie izmeneniy amplitud seysmicheskikh otrazheniy dlya poiskov i razvedki zalezhey uglevodorodov (Investigation of changes in the amplitude of seismic reflections for prospecting and exploration of hydrocarbon deposits), Moscow: Publ. of Gubkin University, 2001, 68 p.

3. Kondrat'ev I.K., Ryzhkov V.I., Kissin Yu.M., Shubin A.V., Sposoby realizatsii i otsenka effektivnosti seysmicheskoy inversii (Seismic inversion implementation and performance evaluation), Moscow: Publ. of Gubkin University, 2011, 62 p.

2. Stepanov A.V., Obrabotka seysmicheskikh dannykh: uchebno-metodicheskoe posobie k kursam povysheniya kvalifikatsii “Petrofizika i geofizika v neftyanoy geologii” (Seismic data processing: educational-methodical manual for refresher courses "Petrophysics and geophysics in petroleum geology"), Kazan': Kazan University, 2013, 24 p.

4. URL: https://geosoftwaresupport.cgg.com/KnowledgeBase

The Srednebotuobinskoye oil and gas field is a linear anticline structure consisting of three large tectonic blocks with different fluid contacts - Central, Eastern and Western. The Central block is under development. Together with its development additional exploration of the field is being actively carried out to clarify contacts and faults controlling the deposits. Field area was completely covered with a 3D seismic survey. Also two prospecting and seven exploration wells have been drilled since 2013. The first problem while drilling exploratory wells in the south of the Central block was the absence of oil saturation in the structure with proven oil saturation at the same levels in its northern part. The question arose either about the existence of additional faults within the Central Block or about the lenticular reservoir. The second problem in the exploited part of the field was wrong structural maps obtained from 3D seismic data on which the placement of production well pads critically dependent. When analyzing structural maps errors it was revealed that most of them are associated with the influence of overlying intrusions, which are a high-velocity anomaly and distort the time and the structural plan of the target Botuobinsky formation accordingly. In order to deal with the described problems it was decided to perform the pre-stack depth migration of 3D seismic data. The following tasks were set for the migration: reconstruction of the structural plan by taking into account the influence of intrusion, improving the focusing of faults, enhancement the quality of all seismic images.

References

1. Kleshnin A.B., Tverdokhlebov D.N., Goguzeva E.I., Melnikov R.S., Modern technology for seismic data processing in Srednebotuobinskoye oil-gas-condensate field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 2, pp. 31–35.

2. Biondi B.L., Concepts and applications in 3D seismic imaging, SEG/EAGE Publications, 2007, 243 p.

3. Biondi B.L., Etgen J.T., Jones I.F., Bloor R.I., Pre-stack depth migration and velocity model building, SEG Publications, 2008, 880 p.

4. Berkhout A.J., Seismic migration: Imaging of acoustic energy by wave field extrapolation, Elsevier Science, 2nd edition, 1985, 286 p.

5. Yilma Ö., Seismic data analysis: Processing, inversion, and interpretation of seismic data, SEG Publications, 2001, 2027 p.

In the 90s of the XXth century, the Udmurt Republic began to significantly reduce the volume of seismic exploration due to the completion of the stage of searching for hydrocarbons in large and medium-sized structural traps. Since 2001, the increase in oil reserves has lagged far behind production volumes. One of the possible ways to increase the geological reserves of oil was the search and exploration of small and very small oil deposits. However, traditional methods do not allow effectively and with sufficient accuracy identifying hydrocarbon deposits and conducting their reliable delineation, which leads to the drilling of a large number of «empty» wells. As a solution to the problem, it is proposed to use the technology of low-frequency seismic exploration, in its different variants, which will significantly reduce the time and financial costs for the search, exploration and involvement in the development of oil fields. The use of low-frequency seismic exploration will significantly reduce the number of production wells drilled by laying exploration and exploration wells, taking into account their further conversion to production wells, as well as by drilling wells in areas of intense fracturing and high oil saturation of the productive reservoir. This would significantly reduce the cost of finding and exploration drilling such geological features, which would make their development cost-effective. Also, the proposed technology can be successfully used in the study of already discovered fields to establish the exact oil-water contact of the hydrocarbon deposit and monitor the state of development of the field.

The article presents the forecast schemes of oil and gas potential of structures searched for by low-frequency seismic exploration, and also presents the advantages of using low-frequency seismic exploration for forecasting and monitoring the development of oil fields in the Udmurt Republic.

References

1. Savel'ev V.A., Neftegazonosnost' i perspektivy osvoeniya resursov nefti Udmurtskoy Respubliki (Oil and gas potential and prospects of development of oil resources of the Udmurt Republic), Moscow - Izhevsk: Publ. of Institute of Computer Science, 2003, 287 p.

2. Meshbey V.I., Seysmorazvedka metodom obshchey glubinnoy tochki (Seismic survey using the common depth point method), Moscow: Nedra Publ., 1973, 152 p.

3. Arutyunov S.L., Karnaukhov S.M., Pozdneukhov S.V. et al., ANCHAR technology for prospecting and monitoring of hydrocarbon deposits (In Russ.), Tekhnologii seysmorazvedki, 2010, no. 1, pp. 58–66.

4. URL: http://www.anchar.ru

5. Kuznetsov O.L., Chirkin I.A., Shtyk A.V., Innovative seismoacoustic technologies for exploration and development of deposits (In Russ.), Burenie i Neft', 2010, no. 2, pp. 3–8.

6. Sharapov I.R., Shabalin N.Ya., Biryal'tsev E.V. et al., Innovatsionnye passivnye mikroseysmicheskie metody v neftegazovoy otrasli – opyt primeneniya v Rossii (Innovative passive microseismic methods in the oil and gas industry – application experience in Russia), Proceedings of international scientific geological conference  “ATYRAUGEO -2015”, Atyrau, 2015.

7. Maksimov L.A., Vedernikov G.V., Yashkov G.N., Geodynamical noise of hydrocarbon pools and passive and active seismic CDPM (In Russ.), Ekspozitsiya Neft' Gaz, 2016, no. 6, pp. 55-64.

The technology of drilling multi-borehole wells (MBW) is widely used; it allows putting into operation an emergency and inoperative well stock, as well as performing work in wells that have developed their reserves. Oilfield service companies are paying increasing attention every year to the development and promotion of new solutions to further improve the effectiveness of this technology and contribute to its dissemination among oil and gas companies. The main advantage of MBW is to increase the drainage area by drilling multi-directional sidetracks from the main hole.

Using the example of object in Western Siberia, a trajectory of a MBW with a horizontal completion and one sidetrack was designed; the length of the horizontal sections was up to 500 m. It is shown that an increase in the inclination angle up to 90° can lead to complications both during drilling and when running the casing into the sidetrack. One of the solutions to prevent such complications and accidents was to change the profile of the main hole. In order to shorten the bok barrel, it is proposed to direct the main barrel to point D along the angle bisector, directed to the middle of the section. A method for changing the profile of a MBW with one sidetrack is proposed, which will reduce the total footage along the well. Comparative calculations of trajectories of wells built in the traditional way (without taking into account the location of the sidetrack branch) and taking into account the coordinates of the point corresponding to the location of the window cut have been performed. As a result of calculations, it was found that for the case under consideration, when the cut-out point of the window is displaced by 700 m from the wellhead, the total length of the sidetrack decreases by 128.8 m, with a displacement of 600 m from the wellhead, by 144.9 m. At the same time, the total length of the well is reduced by 91.7 and 99.6 m, respectively.

References

1. Gel'fgat M.Ya., The development of well drilling technologies - is a key direction in the development of the oil and gas industry (In Russ.), Vestnik Assotsiatsii burovykh podryadchikov, 2020, no. 1, pp. 19–27.

2. Shafigullin R.I., Vakula A.Ya., Mukhametshin A.A. et al., Construction of a multilateral well in Shegurchinskoye field of Tatneft PJSC (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 7, pp. 15–17.

3. Voevodkin V.L., Okromelidze G.V., The development of the sidetracks construction technology at oil fields in Perm region (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 8, pp. 32–35.

4. Gavura A.V., Shafikov R.R., Razumenko V.E., Features in developing offshore fields of "LUKOIL" PJSC (In Russ.), Neft'. Gaz. Novatsii, 2020, no. 10(239), pp. 70–77.

5. Patent 2650161C2 RU, Method of multilateral well construction, Inventors: Bakirov D.L., Fattakhov M.M.

6. Shcherbakov A.V., Detin M.V., Osobennosti proektirovaniya i stroitel'stva dvustvol'nykh skvazhin (Features of the design and construction of double-barreled wells), Proceedings of XIII Conference of young scientists and specialists of the KogalymNIPIneft branch of LLC LUKOIL-Engineering in Tyumen, Shadrinsk: Shadrinskiy Dom Pechati Publ., 2014, pp. 336–350.

7. Shcherbakov A.V., Grechin E.G., Kuznetsov V.G., Changing the profile of directional wells for the further sidetracking (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 7, pp. 92–96.

8. Shcherbakov A.V., Determination of place of additional wellbore drilling in a multilateral well (In Russ.), Stroitel'stvo neftyanykh i gazovykh skvazhin na sushe i na more, no. 2015, no. 10, pp. 18–23.

9. Povalikhin A.S., Kalinin A.G., Bastrikov S.N., Solodkiy K.M., Burenie naklonnykh, gorizontal’nykh i mnogozaboynykh skvazhin (Directional, horizontal and multihole drilling), Moscow: Publ. of TsentLitNefteGaz, 2011, 647 p.

Standard procedures for determining the displacement coefficient assume a single value of this parameter for reservoirs with fixed filtration-capacity properties. For inhomogeneous formations, petrophysical relationships are usually constructed between the values of the displacement coefficients and the filtration and reservoir properties of the formation. However, the generally accepted standard approach does not take into account the structure and mobility of the residual oil. In the proposed article, the authors present the results of experiments showing significant changes in the oil displacement coefficient by water when the displacement conditions change, characterized by different values of the capillary number. Experimental dependences of the displacement coefficients on the capillary number are obtained. It is shown that the standard values of the displacement coefficients, at the maximum values of the capillary numbers, can change multiple times with varying values of the capillary number. This leads to changes in the values of displacement coefficients in the near-well and inter-well areas of the developed formations. Examples of the distribution of displacement coefficients in development elements with the same filtration and reservoir properties, but with changing well placement systems, are given. The influence of well placement systems on changes in the displacement coefficient is shown.

Referencrs

1. Gladkikh E.A., Khizhnyak G.P., Galkin V.I., The method for estimating the oil displacement coefficient based on standard core analysis (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 8, pp. 90–93, DOI: 10.24887/0028-2448-2017-8-90-93.

2. Glazunov P.A., Fedorova A.B., Smetanin A.V. et al., The summary of oil displacement experiments in Tomsk region (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 4, pp. 36–38.

3. Mikhaylov N.N., Ostatochnoe neftenasyshchenie razrabatyvaemykh plastov (Residual oil saturation of developed reservoirs), Moscow: Nedra Publ., 1992, 240 p.

4. Mikhaylov N.N., Tekhnologii dorazrabotki zavodnennykh plastov na osnove issledovaniya struktury i podvizhnosti ostatochnoy nefti (Technologies for further development of flooded formations based on the study of the structure and mobility of residual oil), Collected papers “Novye tekhnologii osvoeniya i razrabotki trudnoizvlekaemykh zapasov nefti i gaza i povysheniya neftegazootdachi” (New technologies of development and exploitation of stranded oil and gas and enhanced oil gas recovery), Moscow: Publ. of  Institut neftegazovogo biznesa N, 2008, 344 p.

5. Mikhaylov N.N., Glazova V.I., Vysokovskaya E.S., Prognoz ostatochnogo neftenasyshcheniya pri proektirovanii metodov vozdeystviya na plast i prizaboynuyu zonu (Forecast of residual oil saturation in the design of methods of stimulation of reservoir and the bottom zone), Moscow: Publ. of VNIIOENG, 1983, 71 p.

6. Mikhaylov N.N., Dzhemesyuk A.V., Kol'chitskaya T.N., Sostoyanie i raspredelenie ostatochnoy nefti v zavodnennykh plastakh (Status and distribution of the residual oil in the flooded layers), Collected papers “Fundamental'nyy bazis novykh tekhnologiy neftyanoy i gazovoy promyshlennosti” (The fundamental basis of the new technologies of the oil and gas industry), Moscow: Nauka Publ., 2000, pp. 204–213.

7. Mikhaylov N.N., Melekhin S.V., Basic ideas about the curves of capillary displacement and their characteristics (review) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 8, pp. 24–28.

8. Mikhaylov N.N., Chumikov R.I., Experimental research of the capillary-pinched phases mobility (In Russ.), Vestnik TsKR Rosnedra, 2009, no. 5, pp. 42–48.

9. Gioia F., Alfani G., Andreutti S., Murena F., Oil mobility in a saturated water-wetted bed of glass beads, J. Hazard Mater., 2003, B97, pp. 315−327, doi: 10.1016/s0304-3894(02)00281-9.

10. Kamath J., Meyer R.F., Nakagawa F.N., Understanding waterflood residual oil saturation of four carbonate rock types, SPE-71505-MS, 2001, https://doi.org/10.2118/71505-MS

11. Saadapoor E., Bryant S. L., Sepehrnoori K., New trapping mechanism in carbon sequestration, Transp. Porous Media, 2010, V. 82, pp. 3−17.

12 Mikhaylov N.N., Polishchuk V.I., Khazigaleeva Z.R., Modeling of residual oil distribution in flooded heterogeneous formations (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 8, pp. 36–39.

13. Zaitsev M.V., Mikhailov N.N., Effect of residual oil saturation on the flow through a porous medium in the neighborhood of an injection well (In Russ.), Izvestiya RAN. Mekhanika zhidkosti i gaza = Fluid Dynamics, 2006, no. 4, pp. 93–99.

14. Mikhaylov N.N., Varlamov D.P., Klenkov K.A., Modeling the impact of well placement systems on the residual oil saturation of flooded formations (In Russ.), Burenie i neft', 2004, no. 1, pp. 13–15.

It is well known, that injection water breakthrough by highly conductive channels leads to rapid watercut of producers. Herewith, the effectiveness of reserves recovery greatly decreases, even though the production from the initial recoverable reserves does not exceed 40-50%. This means that the most oil in place resides beyond the development zone. To correct the occurred situation and improve the efficiency of existing development system, the flow deviation technologies (FDT) are applied. Such technology allows limiting the injection water filtering through flooded pools and forward it to undeveloped oil saturated zones. The experience in applying FDT and watered formations selective shut-off is significant. However, the existing information on implementing the FDT in various geological conditions demonstrates the uncertainty in the technology efficiency. As some researchers mention, the technological effect from applying the flow deviation technology may be positive, negative and neutral. It is highlighted, that some target areas showed no response in producers after the technology implementation. Other areas showed steady decrease of watercut and increase in oil production. There are also reports indicating that FDT implementation resulted in a decrease of oil production and increase of watercut. The paper covers the peculiarities of applying the flow deviation technology (FDT) on modelled oil saturated reservoir and compares the effect of FDT with hydrodynamic effect (changing the injector operation mode). The main objective is to identify the conditions for effective implementation of the technologies.

References

1. Gazizov A.A., Uvelichenie nefteotdachi neodnorodnykh plastov na pozdney stadii razrabotki (Enhanced oil recovery of heterogeneous reservoirs at a late stage of field development), Moscow: Nedra-Biznestsentr Publ., 2002, 639 p.

2. Muslimov R.Kh., Sovremennye metody upravleniya razrabotkoy neftyanykh mestorozhdeniy s primeneniem zavodneniya (Modern methods of development of oil fields with the use the waterflooding), Kazan: Publ. of Kazan University, 2003, 596 p.

3. Grigorashchenko G.I., Zaytsev Yu.V., Kukin V.V. et al., Primenenie polimerov v dobyche nefti (The use of polymers in oil recovery), Moscow: Nedra Publ., 1978, 213 p.

4. Astakhova A.N., Vybor uchastkov i obosnovanie primeneniya potokootklonyayushchikh tekhnologiy pri izvlechenii nefti iz neodnorodnykh kollektorov (Selection of sites and justification of the use of flow diversion technologies when extracting oil from heterogeneous reservoirs): thesis of candidate of technical science, Ufa, 2004.

5. Vladimirov I.V., Al'mukhametova E.M., Abilkhairov D.T., Nasibullina A.A., Features of application flowing technologies in conditionally homogeneous on permeability of oil-exhausted collectors (In Russ.), Neftegazovoe delo, 2017, V. 15, no. 3, pp. 14–21.

6. Vladimirov I.V., Imperfection of the current development system as the main factor in the formation of stagnant areas with oil reserves (In Russ.), Neftegazovoe delo, 2005, no. 4.

The region of Priobskoye field with the lowest permeability is called Gorshkovskaya area. That region is characterized by an ultra-low permeability (less than 0.001 mkm2) and a thin layer reservoir structure. Achimov deposits of the reservoir in Gorshkovskaya area are classified as deep-water alluvial fans. That reservoir has a low effective matrix permeability of approximately 0.004–0.005 mkm2. One of the main questions that must be considered is whether we use waterflooding in case of developing the reservoir of Gorshkovskaya area. This scientific article gives an answer to that question. Four regions of Gorshkovskaya area were selected to implement the experimental part. The first region was developed with the help of depletion drive while other regions were developed with the help of water drive. The comparison of the parameters of the development of selected regions shows that development with the use of waterflooding tends to be more effective for ultra-low permeability reservoirs in case Gorshkovskaya area of Priobskoye field than with the use of depletion.

Additionally 12 regions in Gorshkovskaya area and in Left coast area of Priobskoye field were selected for estimation of recovery factor using the several techniques. The first method for estimating recovery factor was the logarithm of water-oil ratio, the second method was the decline curve analysis, the third method was based on the digital model of the considered reservoir. Those regions were developed with the use of waterflooding. Additionally one region in Gorshkovskaya area was selected for estimation of recovery factor using the digital model. Using decline curve analysis, recovery factor values in Gorshkovskaya area range from 22 to 27%. Using a digital model, recovery factor values equal to 7% (with the use of depletion drive) and 27 % (with the use of water drive). Estimated values of recovery factor show that development with the use of waterflooding tends to be more effective for ultra-low permeability reservoirs in case of Gorshkovskaya area of Priobskoye field than with the use of depletion. The use of waterflooding increases value of recovery factor by 2–3 times as much.

Список литературы

1. Выбор оптимальной системы разработки для месторождений с низкопроницаемыми коллекторами / В.А. Байков, Р.М. Жданов, Т.И. Муллагалиев, Т.С. Усманов // Нефтегазовое дело. – 2011. – № 1. – С. 84–98.

2. Разработка трудноизвлекаемых запасов в регионе деятельности ООО «РН-Юганскнефтегаз» / М. Шабалин, Г. Хабибуллин, Э. Сулейманов [и др.] // SPE-196753-RU. – 2019.

3. Оптимизация проектных решений и систем заканчивания скважин при разработке пластов, характеризующихся сверхнизкопроницаемым и сверхнеоднородными коллекторами / И.И. Родионова, М.А. Шабалин, А.А. Мироненко, Г.И. Хабибуллин // Нефтяное хозяйство. – 2019. – № 10. – С. 72–76.

4. Уолкотт Дон. Разработка и управление месторождениями при заводнении. – М., 2001. – С. 93–94.

5. Fetkovich M.J. Decline Curve Analysis Using Type Curves// SPE-4629. – 1973.

6. Clark Aaron J. Determination of recovery factor in the Bakken Formation // SPE-133719. – 2009.

7. Ling Kegang, He Jun. Theoretical Bases of Arps Empirical Decline Curves // SPE-161767. – 2012.

8. Подбор оптимальных систем разработки для текущих зон бурения в условиях неопределенности геологических и технологических параметров / Д.Р. Нурлыев, И.И. Родионова, Э.П. Викторов [и др.] // Нефтяное хозяйство. – 2018. – № 10. – С. 60–63.

Requirements of targeted optimization are imposed on the hydraulic fracturing operations carried out in the conditions of borderline economic efficiency of fields taking into account geological and technological features. Consequently, the development of new analytical tools for analyzing and planning the productivity of fractured wells, taking into account the structural features of the productive reservoir and inhomogeneous distribution of the fracture conductivity, is becoming highly relevant. The paper proposes a new approach of assessing the vertical hydraulic fracture productivity in a rectangular reservoir in a pseudo-steady state, based on reservoir resistivity concept. The advantage of the methodology is the resulting formulas for well productivity are relatively simple, even for exotic cases of variable conductivity fractures. However, there is a free parameter in the case of modeling the productivity of a hydraulic fracture by the concept. this article describes a systematic approach to determining the free parameter that characterizes the distribution of fluid inflow along the fracture plane, in contrast to the solutions available in the literature for analyzing the productivity of hydraulic fractures. The resulting model allows to conduct an assessment of the influence of various complications in the fracture on the productivity index. The work includes the cases of the presence of fracture damages at the beginning and at the end of the fracture. The results of the obtained solution were confirmed by comparison with the numerical solutions of commercial simulators and analytical models available in the literature.

References

1. Economides M., Oligney R., Valko P., Unified fracture design: Bridging the gap between theory and practice, Texas: Orsa Press Alvin, 2002, p. 141.

2. Cinco L.H. et al., Transient pressure behavior for a well with a finite-conductivity vertical fracture, SPE-6014-PA, 1978, https://doi.org/10.2118/6014-PA.

3. Meyer B.R., Jacot R.H., Pseudosteady-state analysis of finite-conductivity vertical fractures, SPE-95941-MS, 2005, https://doi.org/10.2118/95941-MS.

4. Kang Ping Chen, Production from a fractured well with finite fracture conductivity in a closed reservoir: An exact analytical solution for pseudosteady-state flow, SPE-179739-PA, 2016, https://doi.org/10.2118/179739-PA.

5. Kang Ping Chen, Yan Jin and Mian Chen, Pressure-gradient singularity and production enhancement for hydraulically fractured wells, Geophysical Journal International, 2013, V. 195, no. 2, pp. 923–931.

6. Prats M., Effect of vertical fractures on reservoir behavior – Incompressible–fluid case, SPE-1575-G, 1961, https://doi.org/10.2118/1575-G

The article is devoted to the assessment results of the pilot operation impact on the efficiency of the perspective shelf geological structure development from the shore in arctic climatic conditions on Rosneft Oil Company’s license area. One of the main challenges of the performed study was to determine the technological and economic efficiency of the pilot operation phase as part of field development in comparison with the field development option without pilot operation. The expected effect of the pilot operation phase is the possibility of studies the productive reservoir properties, the results of which will ensure the ашдв вумудщзьуте high efficiency, as well as ensuring early oil production through exploration wells and, as a consequence, accelerating the receipt of the project positive cash flow. The region is characterized by harsh climatic conditions, seasonal restrictions on movement of vehicles, complex geology and relief, as well as the presence of permafrost soils. The main challenge in the performed study was to find a technically feasible and economically viable solution for the perspective structure development, including the construction of infrastructure for the pilot operation of the object. As a result of the study and assessment of various options for the structure development, the main concept of development and construction was adopted, which involves the shelf structure development from the shore using horizontal wells drilled from the onshore well pad, as well as the construction of infrastructure facilities in this zone. Further, options, including with and without the pilot operation phase implementation, were considered for the selected development concept. The comprehensive technical and economic assessment of the project was carried out for the obtained development options. The key factors affecting on the economic efficiency of the pilot operation phase implementation were analyzed in the article, the special role of the special mineral extraction tax regime for the arctic offshore projects is emphasized.

The article provides a review of the results achieved at Rosneft Oil Company upon implementation of a system aimed to improve the operational quality of artificial lift wells in response to negative impact of complicating factors. The key objective of this project is to create a systemized full-cycle process which comprises forecasting, feasibility studies, planning and quality control of well operations, including also at the development designing stage. An important work area is to reduce total unit costs related to taking equipment protection measures and increasing the mean time between failures. The project has six main implementation stages. It provides the principles of creating a unified system across all company subsidiaries to rank the well stock under the “complicating factor’ criteria with a description of principles to categorize complications by their type and severity. It also offers the criteria for listing available technologies which are efficient for certain complications factoring in the complication type and category and the well operation mode. The article gives a brief review of assessing and improving the quality of decisions for selection of measures to protect downhole pumping equipment from complicating factors based on the Feasibility Study Model. It also analyzes organization of the business planning cycle and implementation of the strategy aimed to improve operational efficiency of artificial lift wells in response to negative impact of complicating factors for each subsidiary of the Rosneft Group. The article presents the sequence of activities to forecast the risk of complication factor occurrence at company’s Greenfield assets. It states the importance of the automation and digitization stage in the work to address complications during operations of artificial lift wells using the platform of the corporate information system Artificial Lift Wells. The article demonstrates the efficiency of the implemented system and describes the results achieved.

References

1. Drozdov A.N., Tekhnologiya i tekhnika dobychi nefti pogruzhnymi nasosami v oslozhnennykh usloviyakh (Technology and engineering of oil production using submersible pumps under complicated conditions), Moscow: MAKS press Publ., 2008, 312 p.

2. Topolʹnikov A.S., Prediction of complications in the operation of mechanized wells using the RosPump program (In Russ.), Inzhenernaya praktika, 2014, no. 2, pp. 48–53.

3.  Kosilov D.A., Improving the efficiency of the management of the mechanical well stock in the current macroeconomic conditions (In Russ.), Inzhenernaya praktika, 2015, no. 12, pp. 8–11.

4. Ivanovskiy V.N., New conceptual approach to protection of submersible equipment from scales (In Russ.), Territoriya neftegaz, 2013, no. 9, pp. 12–16.

5. Ivanovskiy V.N., Impact upon the running time of electrically driven centrifugal feed pump units and the pump''s rotation speed in the course of operation of wells which are complicated by a mechanical impurity outflow (In Russ.), Territoriya neftegaz, 2017, no. 9, pp. 58–64.

6. 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.

7. Certificate of registration of a computer program no. 2019617219, Programma informatsionnoy sistemy upravleniya mekhanizirovannym fondom skvazhin (Mechanized well stock management information system program).

An abrupt growth of periodic wells, which are operated by electric submersible pumps (ESP), that is indicated in recent years in all oil companies, leads to development of the mathematical models and tools for its modelling. The simple engineering approaches, which were used earlier, have large errors and do not able to make operative fitting of well and equipment working mode to fast-changing operating conditions. The main difficulty is that one has to deal with non-stationary regime of well operating, when each working cycle, at which the pump is switched on, changes with accumulation cycle, at which the pump is switched off. In this paper the description of mathematical models and the algorithm of solving the problem of fitting the present and optimization the forecast periodic mode is presented. The model simplifications for calculation of reservoir and multiphase flow in the well elements are discussed, which enable to essentially increase the speed of calculations avoiding the noticeable accuracy loss. The comparison with field data is presented on the example of the wells with operable and non-hermetic check valve. It is shown how the leaks in the check valve can be taken into account in the model. The short description of the modules “Analysis of the periodic regime of ESP” and “Serial optimization of conditionally stable mode/Automatic re-enabling mode” is done, which are realized in Rosneft Oil Company for aims of monitoring and optimization of periodic mode of oil wells. Their functions and solvable problems are presented, which help technological service to increase oil rate and to diminish the power inputs at periodic wells.

References

1. Shchelkachev V.N., Lapuk B.B., Podzemnaya gidravlika (Underground hydraulics), Moscow: Gostoptekhizdat Publ., 1949, 525 p.

2. Brill J.P., Mukherjee H., Multiphase flow in wells, SPE Monograph, Henry L. Dogherty Series, V.17, 1999, 164 p.

3. Topol'nikov A.S., Bolotnova R.Kh., Buzina V.A., Agisheva U.O., Mathematical modeling of dynamic processes in oil wells (In Russ.), Voprosy sovremennoy nauki i praktiki, 2014, no. 4(54), pp. 112–119.

4. Topol'nikov A.S., Primenenie metodov matematicheskogo modelirovaniya pri kontrole i optimizatsii nestatsionarnogo rezhima raboty neftyanoy skvazhiny (Application of mathematical modeling methods for monitoring and optimization of unsteady operation of an oil well), Proceedings of Institute of Mechanics. R.R. Mavlyutova, 2016, V. 11, no. 1, pp. 53–59.

5. Topol'nikov A.S., Obosnovanie primeneniya kvazistatsionarnoy modeli pri opisanii periodicheskogo rezhima raboty skvazhiny (Justification of the application of the quasi-stationary model in the description of the periodic well operation mode), Proceedings of Institute of Mechanics. R.R. Mavlyutova, 2017, V. 12, no. 1, pp. 15–26.

6. Volkov M.G., Optimization of low productivity wells cyclic operating (In Russ.), Neftegazovoe delo, 2017, V. 15, no. 1, pp. 70–74.

7. Volkov M.G., Use of the automatic control theory methods to represent the artificial-lift oil wells as an object of control (In Russ.), Problemy sbora, podgotovki i transporta nefti i nefteproduktov, 2017, no. 1, pp. 11–22.

It is known, safety and survivability, serviceability of the equipment is regulated durability by characteristics of his separate units and elements in which there can be initial or operational defects such as superficial different orientation semi elliptical superficial inclined cracks. Numerical methods of calculation allow expanding reliability of received results on the set algorithms of calculation of corresponding models of destruction. Change of a kind of tensely-deformed conditions near to a contour of cracks, at transition from deeper points, to superficial, depends on constraint of deformations along their front. On the basis of experimental results and numerical decisions, diagnostics change of the form defects such as superficial inclined semi elliptical cracks low-cycle cracks is stated. The data of certainly - element modeling are realized on the basis of macro owls of program complex ANSYS. Law of an orientation of development elastoplastic destructions is investigated at low-cycle destruction.

On the basis of deformation criterion of destruction, settlement - experimental, numerical and analytical methods with application of mathematical model of spatial distribution of mechanical properties, settlement - experimental kinetic dependences and critical parameters elastic-plastic destructions for developing inclined superficial low-cycle semi-elliptical cracks in corresponding zones of welded connection are received. And also, methodological positions of limiting conditions of elements of the responsible equipment of the oil, oil-and-gas and petrochemical industry, aviation, space, nuclear and thermal technical equipment from non-uniform metal materials are formulated under nonlinear conditions loading and general methodology of carrying out more exact calculation of durability, survivability and an operational resource at presence in them of defects such as cracks in a wide range of temperature and design features.

References

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2. Makhutov N.A., Makarenko I.V., Makarenko L.V., Analysis and simulation of kinetics of elasto-plastic weld failure in structures at cryogenic temperatures, IOP Conference Series Materials Sci-ence and Engineering, 2019, doi:10.1088/1757-899X/681/1/012030

3. Makhutov N.A., Makarenko I.V., Makarenko L.V., Study of the spatial mechanical inhomogeneity of welded joints of austenitic stainless steels (In Russ.), Zavodskaya laboratoriya, 2004, V. 70, no. 2, pp. 39–49.

4. Makhutov N.A., Makarenko I.V., Makarenko L.V., Kinetics of the multidirectionality of elastic-plastic fracture with allowance for anisotropy of the material properties (In Russ.), Zavodskaya la-boratoriya. Diagnostika materialov, 2020, V. 86, no. 1, pp. 44–50.

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6. Makhutov N.A., Makarenko I.V., Makarenko L.V., Influence of anisotropy of physical and me-chanical properties on the kinetics of cracks in austenitic steels  (In Russ.), Problemy prochnosti, 2004, no. 1, pp. 113–119.

7. ANSYS, 2010. Structural Analysis Guide. 660578.

8. Azuma K., Li Y, Hasegawa K., Evaluation of stress intensity factor interactions between adjacent flaws with large aspect ratios, Proceedings of the ASME pressure vessels and piping conference, 2015, Article no. 45063.

9. Li C.Q., Fu G.Y., Yang W., Stress intensity factors for inclined external surface cracks in pressur-ized pipes, Eng. Fract. Mech., 2016, V. 165, pp. 72–86.

10. Fu G.Y., Yang W., Li C.Q., Stress intensity factors for mixed mode fracture induced by inclined cracks in pipes under axial tension and bending,  Theoretical and Applied Fracture Mechanics, 2017, V. 89, pp. 100 - 109.

11. Panasyuk V.V., Mekhanika kvazikhrupkogo razrusheniya materialov (Mechanics of quasi-brittle fracture of materials), Kiev: Naukova dumka Publ., 1990, 415 p.

12. Panasyuk V.V., Predel'noe ravnovesie khrupkikh tel s treshchinami (Limiting equilibrium of brit-tle bodies with cracks), Kiev: Naukova dumka Publ., 1974, 416 p.

13. Morozov E.M., Raschet na prochnost' pri nalichii treshchin (Strength calculation in the presence of cracks), In: Prochnost' materialov i konstruktsiy (Strength of materials and structures), Kiev: Nau-kova dumka Publ., 1975, pp. 323–333.

14. Makhutov N.A., Makarenko I.V., Makarenko L.V., Studies on the fracture mechanism and kinet-ics of randomly oriented surface semielliptic cracks at the multiaxial stress-strain state with defor-mation criteria of nonlinear fracture mechanics (In Russ.), Problemy prochnosti, 2013, no. 4(424), pp. 91–97.

15. Makhutov N.A., Makarenko I.V., Makarenko L.V., Studies on the fracture mechanism and kinet-ics of randomly oriented surface semielliptic cracks at the multiaxial stress-strain state with defor-mation criteria of nonlinear fracture mechanics, Strength of Materials, 2013, V. 45, no. 4, pp. 454–458.

16. Makhutov N.A., Makarenko I.V., Makarenko L.V., Numerical and experimental study of devel-oping semi-elliptical inclined low-cycle surface cracks (In Russ.), Zavodskaya laboratoriya. Diag-nostika materialov, 2013, no. 11, V. 79, pp. 39–44.

17. Makhutov N.A., Makarenko I.V., Makarenko L.V., Tensely - deformed conditions in conditions of complex circuits loading and non-uniform properties at top of the crack, Abstract of 5-th Interna-tional Conference “Problems of dynamics and strength in gas-turbine construction”: edited by Zinkovskyy A.P., Kyiv, 27-31 May 2014, Kyiv: Publ. of G.S. Pisarenko Institute for Problems of Strength of the National Ac. Sci. of Ukraine, 2014, pp. 159–160.

18. Makhutov N.A., Makarenko I.V., Makarenko L.V., Calculation and experimental analysis of the stress-strain state for in clined semi-elliptical surface cracks, Inorganic Materials, 2017, V. 53, no. 15, pp. 1502–1505.

19. Makhutov N.A., Makarenko I.V., Makarenko L.V., Kinetics analysis and orientation of elastic-plastic deformation and fracture (In Russ.), Zavodskaya laboratoriya. Diagnostika materialov, 2019, no. 6, V. 85, pp. 47–52.

20. Vyatkin V.V., Khabidenov S.O., Toropov E.S., Opyt i perspektivy primeneniya trub s vnutrennim antikorrozionnym pokrytiem dlya truboprovodnykh sistem (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 6, pp. 90-92, DOI:10.24887/0028-2448-2020-6-90-92

21. Fu G.Y., Yang W., Li C.Q., Stress intensity factors for mixed mode fracture induced by inclined cracks in pipes under axial tension and bending, Theoret. Appl. Fract. Mech., 2017, V. 89, pp. 100–9.

The article presents the results of work on the development of an automated system for interpreting deviations from dynamograms based on machine learning tools. The work contains the results of factor analysis of the reasons affecting the accuracy of the dynamometer recording of the sucker rod pump and the reasons affecting the accuracy of the dynamogram interpretation models and the principle of the implementation of the tool for recognizing deviations in work dynamometer sucker rod pump. It has been shown that the accuracy of a dynamogram is influenced by many factors, such as: the state of the polished rod (dimensions) due to deviations caused by abrasion and wear, the deviation of the elastic modulus of the steel grade of the polished rod from the calculated value, the deviation of the Poisson coefficient, and the error from temperature drift by the device itself. It is shown that the quality of the implemented machine learning model will be affected by: the quality of the training sample and the test sample (the number of erroneous interpretations in the samples); prognostic ability of the model itself. The scheme of operation of the system for interpreting deviations from dynamograms and the results of assessing the quality of the developed models are presented. For the model of binary classification of dynamograms, the Fisher metric was 97%, for the multiclass model - 82%, for the multilable model - 87%. The developed automated system for interpreting deviations from dynamograms based on machine learning tools is integrated into the decision support system implemented as part of R&D project “Operational Service” Bashneft PJSOC. The system allows you to quickly identify simultaneously several types of deviations in the dynamogram.
References
1. Bakhtizin R.N., Urazakov K.R., Latypov B.M. et al., The influence of regular microrelief forms on fluid leakage through plunger pair of sucker rod pump (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 4, pp. 113–116.
2. Urazakov K.R., Latypov B.M., Ishmukhametov B.K., Experimental studies of the influence of configuration of regular microrelief of plunger surface on sucker-rod pump delivery, Chemical and Petroleum Engineering, 2018, V. 54, no. 3–4, pp. 172–176.
3. Urazakov K.R., Latypov B.M., Ishmukhametov B.Kh., Study of the influence of form of regular microrelief of the plunger on the output flow of sucker rod pump (In Russ.), Khimicheskoe i neftegazovoe mashinostroenie, 2018, no. 3, pp. 23–25.
4. Yamaliev V.U., Ishemguzhin I.E., Latypov B.M., Friction assessment plunger to barrel of sucker rod pump in design rod string (In Russ.), Izvestiya Samarskogo nauchnogo tsentra RAN, 2017, V. 19, no. 1, pp. 70–75.
5. Mansafov R.Yu., A new approach to the diagnosis of sucker rod pumps work on the dynamometer card (In Russ.), Inzhenernaya praktika, 2010, no. 9, pp. 82–89.
6. Urazakov K.R., Latypov B.M., Komkov A.G., Davletshin F.F., Calculation of the theoretical dynamogram of a differential sucker-rod pump for the production of high-viscosity oil (In Russ.), Oborudovanie i tekhnologii dlya neftegazovogo kompleksa, 2017, no. 4, pp. 41–47.
7. Deng L., The MNIST database of handwritten digit images for machine learning research, IEEE Signal Processing Magazine, 2012, V. 29, no. 6, pp. 141–142.
8. Wu B. et al., Multi-label learning with missing labels for image annotation and facial action unit recognition, Pattern Recognition, 2015, V. 48, no. 7, pp. 2279–2289.
9. Madjarov G. et al., An extensive experimental comparison of methods for multi-label learning, Pattern recognition, 2012, V. 45, no. 9, pp. 3084–3104.
10. Aliev T.A., Rzayev A.H., Guluyev G.A. et al., Robust technology and system for management of sucker rod pumping units in oil wells, Mechanical Systems and Signal Processing, 2018, V. 99, pp. 47–56.
11. Mikhaylov A.G., Shubin S.S., Alferov A.V. et al., Improvement of efficiency of diagnostics of rod pumps with use of deep neural networks (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 9, pp. 122–126.
12. 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.
13. Li K., Xianwen G., Zhongda T., Zhixue Q., Using the curve moment and the PSO-SVM method to diagnose downhole conditions of a sucker rod pumping unit, Petroleum Science, 2013, V. 10, pp. 73–80.
14. Li K., Xianwen G., Zhou H.B., Han Y., Fault diagnosis for down-hole conditions of sucker rod pumping systems based on the FBH-SC method, Journal of Petroleum Science and Engineering, 2015, V. 12, pp. 135–147.

In the field conditions, the gas-oil mixture entering the oil and gas separator from the supply pipeline consists of free gas separated at the separation pressure and a liquid phase with gas dissolved and dispersed in it. Free gas almost instantly passes into the gas space of the separator, the gas dissolved at the separation pressure remains in the liquid leaving the separator, and the dispersed gas is separated in the gas separation zone, and the time of its separation depends on the dispersion (size) of the bubbles. Technological calculations of the process of separating oil and gas in separation equipment are based on determining the ascent time of gas bubbles using the Stokes formula to determine the rate of their ascent. In this case, the main influence on the speed and, accordingly, on the ascent time is exerted by the size of the bubbles. As a rule, in calculations, the size of the bubbles is set based on data from field practice, or on the basis of experimental data. At the same time, there are theoretical methods for calculating the size of gas bubbles formed in the flow of a gas-liquid mixture entering an oil and gas separator. The paper gives an assessment of the applicability of these methods in technological calculations of the size of the gas separation zone of oil and gas separators, taking into account the time recommended by the field practice for the retention of liquid in this zone. The results of comparative calculations of the gas separation process for various types of oils in standard separation equipment are presented. It is shown that the most acceptable method is based on determining the average volume-surface diameter of bubbles formed in the gas-liquid mixture inlet nozzle. It was found that in the absence of experimental data, it is possible with accuracy acceptable for design calculations to use this technique to determine the size of gas bubbles in the gas-liquid mixture entering the separator degassing zone. Formulas were obtained for calculating the diameter of the apparatus and the length of the degassing zone with the filling factor of the separator equal to 0.5, depending on the ascent rate of the bubbles of the calculated size. This approach is used in the methods of technological calculation of oil and gas separators, oil and gas separators with water discharge, degassers, i.e. devices with a gas separation zone.

References

1. RD 39-0004-90. Rukovodstvo po proektirovaniyu i ekspluatatsii separatsionnykh uzlov neftyanykh mestorozhdeniy, vyboru i komponovke separatsionnogo oborudovaniya (Guidelines for the design and operation of oil field separation units, selection and layout of separation equipment), Ufa: Publ. of VNIISPTneft', 1990, 69 p.

2. Daletskiy V.M., Efimov V.B., Shlykova M.P., Eksperimental'noe izuchenie generirovaniya i otdeleniya melkodispersnoy gazovoy fazy v gazozhidkostnoy smesi (Experimental study of the generation and separation of a finely dispersed gas phase in a gas-liquid mixture), In: Problemy obustroystva i ekspluatatsii vysokoobvodnennykh neftyanykh mestorozhdeniy (Problems of arrangement and operation of highly watered oil fields), Kuybyshev: Publ. of Giprovostokneft', 1985, pp. 77–82.

3. Daletskiy V.M., Efimov V.B., Shlykova M.P., Razrabotka metoda rascheta razdeleniya gazozhidkostnykh smesey v separatsionnoy emkosti (Development of a method for calculating the separation of gas-liquid mixtures in a separation tank), In: Razrabotka i vnedrenie effektivnoy tekhniki i tekhnologii dobychi nefti (Development and implementation of effective equipment and technology for oil production), Kuybyshev: Publ. of Giprovostokneft', 1986, pp. 27–31.

4. RD 0352-131-98. Degazatory. Metodika tekhnologicheskogo rascheta (Degassers. Technological calculation method), Podol'sk: Publ. of DAO TsKBN, 1998, 55 p.

5. Medvedev V.F., Sbor i podgotovka neustoychivykh emul'siĭ na promyslakh (Gathering and preparation of unstable emulsions in the fields), Moscow: Nedra Publ., 1987, 144 p.

Modern problems related to the presence of chlorine-organic compounds (COC) in crude oil, its production and processing, and sources of COC in oil are considered. The tasks set by modern regulatory requirements for the content of COC in oil and naphtha and the possibility of solving them using analytical methods of existing standards are considered in particular. It is shown that the existing methods for determining COC in oil are not optimal. There is an urgent need to expand analytical methods, increase their accuracy and informativeness.

An important aspect related to the sources of the appearance of COC in oil is noted, namely, one of which is natural, determining some components of crude oil, and the other source is chlorine-containing oilfield reagents used at various stages of oil production, transportation and preparation, as well as products of their thermal and chemical transformations. It is assumed that the formation of COC can occur as a result of hydrochloric acid treatments, hydrolysis of chloride salts, and the interaction of oil components with hydrochloric acid. It is noted that understanding the sources of COC in oil will minimize the risks during its processing. Special tests performed using chromatography-mass spectrometry evaluated the effect of the dosage and nature of the chemical reagents used on the mass fraction of COC in oil. In particular, it was shown that wax solvents containing organochlorine components in working dosages lead to an increase in the content of COC in oil. An important aspect related to the sources of COC appearance in oil is considered. Understanding this aspect will help to minimize the risks associated with organic chlorides during processing. In addition, it is indicated that analytical methods should be developed or modified to control COC in the oilfield reagents used, research should be conducted on the possible generation of COC in the implementation of well acid treatment technologies, and the influence of oil composition on their quantity should be taken into account.

References

1. Khutoryanskiy F.M., Organochlorine compounds in oil. History of the issue and problems of the present (In Russ.), Mir nefteproduktov. Vestnik neftyanykh kompaniy, 2002, no. 3, pp. 6–7.

2. Li X., Wu B., Understanding to the composition and structure of organic chlorides in petroleum and its distillates, Petroleum Science and Technology, 2019, DOI: 10.1080/10916466.2018.1514407.

3. Okhlopkov A.S., Svoystva tovarnoy syroy nefti, pozvolyayushchie identifitsirovat' istochnik neftyanogo zagryazneniya okruzhayushchey prirodnoy sredy (Properties of commercial crude oil, allowing to identify the source of oil pollution of the environment): thesis of candidate of chemical science, Nizhniy Novgorod, 2015.

4. Novikov E.A., Analytical methods for quality control of petroleum and petroleum products (In Russ.), Mir nefteproduktov, 2019, no. 7, pp. 39–50.

5. Dutta M., Pathiparampil A., Quon D. et al., Total chloride analysis in petroleum crude samples: Challenges and opportunities, Chemistry Solutions to Challenges in the Petroleum Industry ACS Symposium Series, Washington: American Chemical Society, 2019, V. 1320, Ch. 11, pp. 281–310, DOI: 10.1021/bk-2019-1320.ch011.

6. Podlesnova E.V., Botin A.A., Dmitrieva A.A. et al., Chromatographic method for determining organochlorine compounds in oil (In Russ.), Sorbtsionnye i khromatograficheskie protsessy, 2019, V. 19, no. 5, pp. 581–587, DOI: 10.17308/sorpchrom.2019.19/1173.

7. Atashgahi S., Liebensteiner M.G., Janssen D.B. et al., Microbial synthesis and transformation of inorganic and organic chlorine compounds, Front. Microbiol., 2018, V. 9, pp. 1–22, URL: https://doi.org/10.3389/fmicb.2018.03079.

8. Kozlov C.A., Frolov D.A., Kuz'mina E.P. et al., Establishment of reasons for the formation of chloric-organic compounds in commodity oil (In Russ.), Neftepromyslovoe delo, 2019, no. 5(605), pp. 65–69.

9. Sinev A.V., Devyashin T.V., Kunakova  A.M. et al., The problem of the formation of volatile organochlorine compounds during the initial distillation of oil as a result of decomposition of chemicals containing salts of quaternary ammonium compounds (In Russ.), PRONEFT''. Professional'no o nefti, 2019, no. 4(14), pp. 63–69.

10. Khutoryanskiy F.M., Chloric-organic compounds. Distribution by fractions and methods of removal from oil at the stage of its preparation for processing (In Russ.), Mir nefteproduktov. Vestnik neftyanykh kompaniy, 2002, no. 4, pp. 9–13.      

11. Wu B., Li Y., Li X. et al., Organochlorine compounds with a low boiling point in desalted crude oil: identification and conversion, Energy Fuels, 2018, V. 32, no. 6, pp. 6475–6481, https://doi.org/10.1021/acs.energyfuels.8b00205.

12. Tat'yanina O.S., Abdrakhmanova L.M., Sudykin S.N., Zhilina E.V., Obrazovanie legkoletuchikh khlororganicheskikh soedineniy pri pervichnoy peregonke nefti v rezul'tate razlozheniya khimicheskikh reagentov, soderzhashchikh soli chetvertichnykh ammonievykh soedineniy (Formation of volatile organochlorine compounds during primary distillation of oil as a result of decomposition of chemical reagents containing salts of quaternary ammonium compounds), Proceedings of TatNIPIneft', 2017, V. 85, pp. 363–369.

13. Huang K.G., Zhu Y.A., Characterization of nonmetal chloride salts and their removal from crude oil, Chemistry Solutions to Challenges in the Petroleum Industry ACS Symposium Series, Washington: American Chemical Society, DC, 2019, V. 1320, Ch. 12, pp. 311–326, DOI: 10.1021/bk-2019-1320.ch012.

14. Gray M.R., Eaton P.E., Le T., Inhibition and promotion of hydrolysis of chloride salts in model crude oil and heavy oil, Petroleum Science and Technology, 2008, V. 26, pp. 1934–1944, DOI: 10.1080/10916460701428607.

Landslides and non-stable condition of ground are significant hazards for underground main pipelines, because landslides lead to shift of ground along and crossing direction of pipeline. Underground pipelines may be deformed axially or in radials due to landslide. Such deformations frequently lead to leakages from pipeline which in its turn can be serious hazard for environment and cause necessity to halt the pipeline functioning. Upon selection of pipelines route the areas under effect of landslide should be excluded. If such exclusion is impossible they should be researched to accept relevant measures. The article is devoted to development of method for constructing underground pipeline taking into account hazard of landslide processes. As a result of held analysis the condition determining possible utmost effect of leakages and ruptures due to landslides are defined. The recommendations to achieve possible low level of effect of seismic hazard on pipeline are formulated. According to these recommendations some unwanted functional dependence between major parameters obtained as a result of held researches should be removed in practice. The route of pipeline should be divided on non-equal parts in line with given order and increase of length of these parts should be accompanied by decrease of horizontal shifts. More lengthy parts of pipeline should be installed at farthest distance from zone of possible seismic activity leading to landslides developing in some order. The proposed method of pipeline installation could lead to minimum possibility of such events as leakages and rupture caused by landslides.

References

1. Marinos V., Stoumpos G., Papathanassiou G. et al., Landslide geohazard for pipelines of natural gas transport, Bulletin of the geological society Greece, 2016, V. 50, no. 2, pp. 845-864, doi:https://doi.org/10.12681/bgsg.11791.

2. Konovalov A., Gensiorovskiy Y., Lobkina V. et al., Earthquake – Induced landslide risk assessment: an example from Sakhalin Island, Russia, Geosciences, 2019, V. 9, 305 p., http://doi:10.3390/geosciences9070305

3. Froude M.J., Petley D.N., Global fatal landslide occurrence from 2004 to 2016, Nat. hazards Earth Syst. Sci., 2018, V. 18, pp. 2161–2181, http://doi.org/10.5194/nhess-18-2161-2018.

4. Sweeney M., Terrain and geohazard challenges facing onshore oil gas pipelines, Thomas Telford Publishing, 2005, 758 p.

5. Wenkai F., Runqiu H., Jintao L. et al., Large – scale field trial to explore landslide and pipeline interaction, The Japanese Geotechnical, 2015, http://dx.doi.org/10/1016/j.sandf.2015.10.011 .

6. De Risi R., De Luca F., Oh-Sung Kwon, Sextos A., Scenario-based seismic risk assessment for buried transmission gas pipelines at regional scale, J. Pipeline Syst. Eng. Pract., 2018, V. 9(4), DOI: 10.1061/(ASCE)PS.1949-1204.0000330

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9. Asadov Kh.G., Synthesis of optimal subsystems for processing measurement information based on and parallel converters (In Russ.), Izmeritel'naya tekhnika, 2002, no. 2, pp. 19–21.

10. Asadov Kh.G., Application of the principle of parametric dimensionality reduction for the synthesis of one subclass of information systems and planning a measurement experiment (In Russ.), Izmeritel'naya tekhnika, 2003, no. 6, pp. 3–6.

The paper presents results of an analysis of the wall waxing effect on the thermal-hydraulic parameters of oil along a non-isothermal section of a 70 km long main oil pipeline with a diameter of 1020 mm.

The paper presents the results of numerical modeling performed using the dynamic CFD simulator OLGA SIS SLB in a specialized calculation module for predicting the waxing process WAX DEPOSITION. The research is a continuation of the previously carried out studies of the influence of deposits on the inner wall of an oil pipeline on its thermal-hydraulic efficiency. Experimental confirmation of the possible positive effects of the presence of a natural protective coating on the inner surface of the pipeline in the form of a layer of asphalt-resin-paraffin deposits have already been done previously by the authors according to average indicators. In this article the results is the use of a dynamic modeling process are considered. Dynamic modeling allows to take into account not only the physics of the process in dependence on external thermobaric conditions, but also its kinetics. The results of dynamic modeling are presented in the form of temporal trends and profiles along the length. That made it possible to numerically measure the thermal-hydraulic efficiency of the near-wall sediment layer, taking into account the non-isothermality and kinetic changes of the process. In particular, the high thermal insulation properties of the sediment layer have been confirmed even with its insignificant thickness that makes it possible to significantly reduce heat transfer and significantly increase the final flow temperature (including the average along the pipeline). Thus, that led to a decrease in the average viscosity and a decrease in the rate of deposition growth. The total effect of a thin (only 2 mm) layer of deposits on the inner surface of the oil pipeline with the inner diameter of 1020 mm was expressed in a significant decrease in the pressure drop even for a short section of 70 km. It is shown the need for further study of the issue in order to develop technologies and effective methods of the waxing process to optimize the costs of in-line cleaning and inhibition of deposits. That is important both for relatively cold and hot non-isothermal sections of oil pipelines.

References

1. Karimov R.M., Sunagatullin R.Z., Tashbulatov R.R., Dmitriev M.E., Study of wax deposition reasons in non-isothermal main pipelines for hot pumping of high-viscosity waxy oil (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 1, pp. 87–91.

2. Sunagatullin R.Z., Karimov R.M., Tashbulatov R.R., Mastobaev B.N., The study of the kinetics of the process of oil wax deposition in main pipeline operating conditions (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 11, pp. 124–127.

3. Sunagatullin R.Z., Karimov R.M., Tashbulatov R.R., Mastobaev B.N., Study of the causes for wax deposition under the operating conditions of main oil pipelines (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2020, V. 10, no. 6, pp. 610–619.

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11. Coutinho J.A.P., Daridon J.L., The limitations of the cloud point measurements techniques and the influence of the oil composition on its detection, Petrol. Sci. Technol., 2005, V. 23, pp. 1113–1128, DOI: 10.1081/lft-200035541.

12. Coutinho J.A.P., Pauly J., Daridon J.L., A thermodynamic model to predict wax formation in petroleum fluids, Braz. J. Chem. Eng., 2001, V. 18(4), pp. 411–422.

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The article provides a retrospective analysis of the emergence of prerequisites for the creation of designs of universal pumping units: from the first patents registered in the 1940s to modern technical solutions used at industrial facilities. The possibility of industrial application in the oil industry of fundamentally new types of vane pumps with a combined design of the impeller and rotor of the electric motor, which received a recent impetus to their spread with the development of electric motor technologies, is considered. The fundamental difference between these types of pump is the transmission of the torque to the impeller not through the shaft, but through the rim of the wheel, which is also the rotor of the electric motor. The absence of a shaft provides a number of advantages, in particular, it leads to an increase in suction capacity, an increase in pressure characteristics and an increase in operational properties – all this together increases the scope of industrial application of new types of pumps. One of the potential applications of a compact pump of the horizontal type can be the rocking of a frozen oil pipeline by tapping the coil at special points of the pipeline route. From the point of view of transporting high-viscosity oil, the design of this type also looks promising; in addition, the possibility of influencing the transported medium by an electromagnetic field is noted. The possibility of using removable impellers of various types for a hollow pump-electric motor is considered, which can significantly increase the scope of application of new types of pumps.

References

1. Patent DE688114C, Elektrisch angertriebene schiffsschraube (Electrically powered propeller), Inventor: Kort L.

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3. Yakovlev A. Yu., Sokolov M.A., Marinich N.V., Numerical design and experimental verification of a RIM-driven thruster, Proceedings of the Second International Symposium on Marine Propulsors smp’11, Hamburg, Germany, June 2011, Hamburg, 2011, pp. 396-402, URL: https://www.marinepropulsors.com/smp/files/downloads/ smp11/Paper/FA2-1_Yakovlev.pdf.

4. Yan Xinping, Liang Xingxin, Ouyang Wu et al., A review of progress and applications of ship shaft-less rim-driven thrusters, Ocean Engineering, 2017, V. 144, pp. 142–156.

5. Sharkh S.M., Lai S.H., Turnock S.R., Structurally integrated brushless PM motor for miniature propeller thrusters, IEEE Proc. Elect. Power Appl., 2004, V. 151(5), pp. 513–519.

6. Pashias C., Turnock S.R. Hydrodynamic design of a bi-directional, rim-driven ducted thruster suitable for underwater vehicles (Ship Science Reports, 128), Southampton, UK: University of Southampton, 2003, 52 p.

7. Lea M., Thompson D., van Blarcom B. et al., Scale model testing of a commercial rim driven propulsor pod, J. Ship Prod., 2002, V. 19(2), pp. 121–130.

8. Andersen T.P., Design of rim driven water-jet pump for small rescue vessel: Master's thesis in the Nordic master in maritime engineering, Chalmers University of Technology, 2014, URL: https://publications.lib.chalmers.se/records/fulltext/203941/203941.pdf

9. Schmirler M., Netrebska H., The design of axial shaftless pump, EPJ Web of Conferences, 2017, V. 143, DOI: 10.1051/epjconf/201714302104

10. Patent US6254361B1, Shaftless canned rotor inline pipe pump, Inventor: Sabini E.P.

11. Patent US4806080A, Pump with shaftless impeller, Inventors: Shotaro Mizobuchi, Katsumi Sasaki, Yoshikazu Kimura.

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Oil fields development is always followed by the influence on all the natural environment components, including soils. On the one hand, there is a mechanical disturbance of the soil cover, leading to its removal or compaction, a change in the existing structure of the soil profile, on the other hand, the qualitative characteristics of the soil (geochemical background) change. The consequences of technogenic interference in the natural environment (disruption of the natural state of natural complexes) are diverse. The soils are characterized by changes in water-physical properties, violation of oxygen regime, salinity, etc. These changes are recorded through monitoring observations. In accordance with the terms of subsoil use at deposits located on the territory of the Republic of Sakha (Yakutia), subsoil users assess the background (before the start of large-scale resource development) and current (field development) state of the natural environment.

The article presents the results of the analysis of the current geochemical state of the soil cover of hydrocarbon deposits in the southwestern part of the Republic of Sakha (Yakutia), developed by Surgutneftegas PJSC. Changes that have occurred in the soils during the development of deposits are traced. It is noted that the formation of the soil cover was significantly influenced by the harsh climatic conditions. It is shown that soil processes are seasonal and develop in that part of the soil that has time to warm up during the warm season of the year. The main features of soils and soil formation are the relatively small thickness of the soil profile, the absence of the removal of the products of soil formation and weathering outside the active layer and their accumulation in the soil, and the slowdown in the biological cycle of substances and energy. To date, the development of hydrocarbon deposits has not had a visible effect on the geochemical state of the soil cover. The soils of the fields are characterized by a heavy granulometric composition. The content of petroleum products does not exceed the approximate permissible concentration. The increased content of some heavy metals is due to the natural features of the area.

References

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2. Elovskaya L.G., Klassifikatsiya i diagnostika merzlotnykh pochv Yakutii (Classification and diagnostics of permafrost soils in Yakutia), Yakutsk: Publ. of Yakut branch of SB AS USSR, 1987, 172 p.

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5. Gennadiev A.N., Pikovskiy Yu.I., Tsibart A.S., Smirnova M.A., Hydrocarbons in soils: Origin, composition, and behavior (Review) (In Russ.), Pochvovedenie, 2015, no. 10, pp. 1195–1209, DOI: 10.7868/S0032180X15100020

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