The classical hierarchical enterprise management system, which has proven its effectiveness, allows you to distribute areas of work correctly, to determine the scope of duties of each employee and structural subdivision. This structure also allows you to build a distinct interaction within your functional unit. However, this structure also has its drawbacks. For example, an artificial limitation within its area of capabilities of active, so-called ‘passionate’, employees is a disadvantage of a hierarchical system with narrow-focused units. It is impossible for them to implement their ideas and proposals, which are often not included in the scope of duties of their subdivision or unit. In order to overcome the barriers created by the hierarchical system that prevent active employees from realizing their ideas, an alternative platform for horizontal non-hierarchical communication was created at Irkutsk Oil Company, and it is called "Team of Great Opportunities" or TGO. The article deals with the mechanisms of functioning, the principles of making and implementing decisions, as well as the results of the activity of the specified corporate movement. The main area for the ideas implemented within this movement was the development of a safe work practices culture. In total, 12 project teams participate in the TGO with an average of 12 people in each team. Participants can be in different positions in the corporate entity, have different experience and expertise. At the same time, working within the horizontal structure of TGO, all these employees are working equally on the problematic issues chosen by themselves or on innovative ideas proposed by them. The effectiveness of TGO is proved by successfully completed projects; one example of those is discussed in the article.

References

1. Dozortsev A.O., Oil company structure development strategy: advantages and disadvantages (In Russ.), Problemy ekonomiki i upravleniya neftegazovym kompleksom, 2009, no. 2, pp. 32–36.

2. Kotter J.P., Leading change, Harvard Business School Press, 1996.

The application of the sequence-stratigraphic analysis of seismic profiles throughout most of the sedimentary cover of the Nepa-Botuoba anteclise (NBA) is confined by lateral extension of thick dolerite and salt series partly dampened and deformed the signal. This problem was solved by using the sequence-stratigraphic modeling method, based primarily on lithological-facial and facies-cyclic analyses of reference wells core and tracking the boundaries of sequences over the area. The basis for the research was a combination of geological and geophysical data, including the geophysical well logging data specifically radioactive, density and acoustic logs, as well as the results of layer-by-layer lithological and sedimentological core description. A regional sequencing-stratigraphic model along the northeast-southwest profile in the transition continent-basin zone has been constructed relied on the results analysis of all obtained data. Four third-order sequences have been distinguished in the interval of the Nepa and Tira horizons, as also the system tracts have been characterized. The fifth sequence is timed to the Danilovsky horizon. Sequences SQ1 and SQ2 are indicative of the area development at the Nepa stage. The main ablation of terrigenous material in Nepa time was in process in the southeast direction. On the southern limb of the NBA due to the gentle slope of the basin bottom, material evacuation was less active. The southern part of the profile shows the features of sedimentation in the transitional coastal-marine zone of the relatively small epicontinental basin, where the terrigenous material was accumulated from the NBA and the Angara-Lena step. Designing of the well profile in the interval SQ3 and SQ4 allowed to show the sedimentation basin development in the Tira time and the carbonate platform evolution. For the first time for this area, deposits of low-stand systems tract (LST) for the fifth sequence, being carbonate-clay fans from the Tira carbonate platform formed during the pre-Danilov stratigraphic hiatus, have been identified. The position was clarified and the previously established stratigraphic unconformities were confirmed. The results obtained are consistent with and supplement the previously obtained data on sedimentation stages in the Prilensk-Nepa structural-facies zone. The sequence-stratigraphic profile construction had made it possible to clarify the correlation and prognosticate the reservoir areal extent.

References

1. Plyusnin A.V., Nedelko O.V., Vilesov A.P., Cherepkova A.A., Maksimova E.N., Sequence stratigraphic model of Nepa and Tira Vendian Formations located in the central part of the Nepa Arch (the Nepa-Botuoba anteclise, Sibeian Platform) (In Russ.), Neftegazovaya Geologiya. Teoriya i praktika. 2019, V. 13, no. 2,  URL: http://www.ngtp.ru/rub/2019/13_2019.html

2. Plyusnin A.V., Structural model of the Vendian section belonging to the north-eastern part of the Nepa-Botuoba anteclise, based on the structural cross-sections and sequence-stratigraphic modeling concerning Nepa Arch and Mirny Ridge areas (In Russ.), Neftegazovaya Geologiya. Teoriya i praktika. 2019, V. 14, no. 3, URL: http://www.ngtp.ru/rub/2019/30_2019.html

3. Resheniya chetvertogo mezhvedomstvennogo regional'nogo soveshchaniya po utochneniyu i dopolneniyu stratigraficheskikh skhem venda i kembriya vnutrennikh rayonov Sibirskoy platformy (Decisions of the fourth Interdepartmental Regional Stratigraphic Meeting to clarify and supplement the Vendian and Cambrian stratigraphic schemes of the inner regions of the Siberian Platform), Novosibirsk: SNIIGGiMS, 1989, 40 p.

4.  Shemin G.G., Geologiya i perspektivy neftegazonosnosti venda i nizhnego kembriya tsentral'nykh rayonov Sibirskoy platformy (Nepsko-Botuobinskaya, Baykitskaya anteklizy i Katangskaya sedlovina) (Geology and oil and gas potential Vendian and Lower Cambrian deposits of central regions of the Siberian Platform (Nepa-Botuoba, Baikit anteclise and Katanga saddle)): edited by Kashirtsev V.A., Novosibirsk: Publ. of SB RAS, 2007, 467 p.

5. Mel'nikov N.V., Vend-kembriyskiy solerodnyy basseyn Sibirskoy platformy (Stratigrafiya, istoriya razvitiya) (Vendian-Cambrian salt pool of the Siberian platform (Stratigraphy, history of development)), Novosibirsk: Publ. of SB RAS, 2009, 148 p.

6. Kovalevskiy O.P., Margulis L.S., Dopolnenie 1. Sekvens-stratigraficheskie podrazdeleniya (Appendix 1. Sequence-stratigraphic units), In: Dopolneniya k stratigraficheskomu kodeksu Rossii  (Additions to the stratigraphic code of Russia), St. Petersburg: Publ. of VSEGEI, 2000, pp. 59–66.

7. Allen J.L., Current ripples, Amsterdam: North Holland Comp., 1968, 433 r.

8. Catuneanu O., Principles of sequence stratigraphy, Amsterdam: Elsevier, 2006, 375 p.

9. Einsele G., Sedimentary basins: Evolution, facies, and sediment budget, Berlin: Springer-Verlag, 2000, 792 p.

10. Fedonkin M.A., Ivantsov A.Yu., Ventogyrus, a possible siphonophore-like trilobozoan coelenterate from the Vendian sequence (late Neoproterozoic), northern Russia. In: The rise and fall of the Ediacaran biota: edited by Vickers-Rich P., Komarower P., Geological Society of London, 2007, Special Publication no. 286, pp. 187–194.

11. Grazhdankin D.V., Maslov A.V., Sequence stratigraphy of the upper Vendian of the East European Craton, Doklady Earth Sciences, 2009, V. 426, pp. 517–521.

12. Posamentier H.W., Allen G.P., Siliciclastic sequence stratigraphy: concepts and applications, SEPM, Concepts in Sedimentology and Paleontology, 1999, no. 7, 210 p.

13. Scotese C.R., Atlas of Earth history, Texas, Arlington, 2001, 52 p.

The article highlights the volume of work performed related to the search and exploration of deposits. The article considers anomalous (atypical) objects identified by the company's geologists in the areas of the Irkutsk region and the Republic of Sakha (Yakutia), identified during geological exploration. Large barrier-type carbonate structures surrounding the paleodepression of the Irkutsk amphitheater have been mapped. The reservoir is represented by pore-cavern type dolomites formed from limestone by secondary processes. The necessary and sufficient criteria for searching for hydrocarbon deposits in the Osinskian horizon have been developed. Structural and tectonic objects were found in the Mirninsky region (Yakutia) using 3D seismic survey. The conceptual scheme of distribution of bar bodies of the Botuobinskian and Ulakhanskian horizons is presented. Significant amounts of oil resources were identified. Based on the generalization of seismic survey materials and deep drilling data, a large sandy strip in the Parfenovskian horizon with significant hydrocarbon potential has been localized, extending over the Bolshetirsky, Verkhnetirsky, Yalyksky and Verkhnekatangsky license areas. The properties of reservoirs based on well data are given. Fluvial system of the Ayanskoye field is considered, paleoflows and microhills of the basement in the form of a pulse of seismic reflecting horizons are dedicated. The drainage system is mapped in detail. The dependence of net to gross shale and distance from the geomorphological bodies is revealed. A large isometric anomaly has been identified at the Yaraktinskoye field, presumably an ancient paleovolcano with a total area of more than 60 km2. The genesis issues are considered and the forecast of the distribution of a terrigenous reservoir associated with the features of sedimentation of an ancient structure is given. The prospects of the object associated with the appearance of new reservoirs in the section of wells are given. As a result of exploratory drilling and 3D seismic surveys to the south of the Dulisminskoye and Yaraktinskoye fields at a distance of 45 km from the latter, a sandbar in the Yaraktinskian horizon was found and mapped down the dip of monocline structure, from which the rates of hydrocarbon inflows production were obtained. Properties of reservoirs are given.

References

1. Kolotovkina M.Yu., Facial zoning of the Vendian productive deposits of the Yaraktinskoe oil and gas-condensate field (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2018, no. 3, pp. 14–25.

2. Myshevskiy N.V., Ignalina Barrier Reef – a new promising object on the Nepa Arch (In Russ.), Geologiya i geofizika, 1991, no. 11, pp. 99–107.

3. Shemin G.G., Geologiya i perspektivy neftegazonosnosti venda i nizhnego kembriya tsentral'nykh rayonov Sibirskoy platformy (Nepsko-Botuobinskaya, Baykitskaya anteklizy i Katangskaya sedlovina) (Geology and oil and gas potential Vendian and Lower Cambrian deposits of central regions of the Siberian Platform (Nepa-Botuoba, Baikit anteclise and Katanga saddle)): edited by Kashirtsev V.A., Novosibirsk: Publ. of SB RAS, 2007, 467 p.

Complex geology, post-depositional alteration, and physicochemical features of sediments and pore fluids often pose problems to oil carbonate reservoir development planning. Meanwhile, lapse-time (4D) shallow electromagnetic (TEM) surveys may be a good tool to monitor waterflooding used for formation pressure maintaining and oil recovery enhancement in highly resistive carbonate reservoirs. Testing at an area developed by the Irkutsk Oil Company, with regard to key sweep efficiency criteria, has demonstrated good fit of injection volumes inferred from TEM data to real values, based on contrast of resistivity. The forecast of the displacement of the waterflooding front was made for five injection wells. These results have been obtained for the first time for a carbonate reservoir in East Siberia and are useful to enhance petroleum production in the region.

The parameters of the observation network and the intervals of the soundings were determined on the basis of hydrodynamic modeling of the reservoir and synthetic modeling of TEM signals. Three stages of full-scale electrical exploration were carried out. The use of TEM technology made it possible to verify the geological model of the oil reservoir structure and assess the type of prevailing pore space near the injection wells. The results of electrical exploration for predicting the displacement of the waterflooding front were confirmed by water breakthroughs in three production wells.

References

1. Ryzhkov V.I., Razrabotka kriteriev prognoza vysokoproduktivnykh zon v osinskom gorizonte po dannym seysmorazvedki (Development of forecast criteria for highly productive zones in the Osinsky horizon based on seismic data), Moscow: Publ. of Gubkin University, 2018.

2. Wolcott D., Applied waterflood field development, Energy Tribune Publishing, 2009, 417 p.

3. Kolesov V.A., Romantsov A.S., Nazarov D.V., Vtorichnaya pustotnost' karbonatnykh porod – rol' i metody izucheniya (Secondary voidness of carbonate rocks – the role and methods of study), Proceedings of the fifth international conference GeoBaikal’ 2018, Irkutsk, 11–17 August 2018.

4. Mandel'baum M.M., Rabinovich B.I., Surkov V.S., Geofizicheskie metody obnaruzheniya neftegazovykh zalezhey na Sibirskoy platforme (Geophysical methods for detecting oil and gas deposits on the Siberian platform), Moscow: Nedra Publ., 1983, 182 p.

5. Van'yan L.L., Osnovy elektromagnitnykh zondirovaniy (Fundamentals of electromagnetic sounding), Moscow: Nedra Publ., 1965, 109 p.

6. Sharlov M.V., Buddo I.V., Misyurkeeva N.V., Transient electromagnetic surveys for high resolution near-surface exploration: basics and case studies, First break, 2017, V. 35, no 9, pp. 63–71.

7. Pospeev A.V., Buddo I.V., Agafonov Yu.A. et al., Sovremennaya prakticheskaya elektrorazvedka (Modern practical electrical exploration), Novosibirsk: Geo Publ., 2018, 231 p.

8. Zimin S.V., Burdakov D.A., Sibilev V.N. et al., Planirovanie sistemy PPD na primere odnogo iz karbonatnykh mestorozhdeniy kompanii INK (Planning of reservoir pressure maintenance system on the example of one of the carbonate fields of the INK company), Proceedings of the fifth international conference GeoBaikal’ 2018, Irkutsk, 11–17 August 2018.

The article presents the geological structure and describes the history of the Bolshetirskoye oil field - one of the most prospective fields of the Irkutsk region. The Osinskian productive horizon is represented by weakly fractured limestones and dolomites of the pore-cavern type formed as a result of secondary processes fr om limestones. The formation is characterized by abnormally high pressure and a significant content of hydrogen sulfide. Conditions incompatible with further drilling occur when drilling a reservoir: absorption of the drilling mud and gassing. The article considers the types of geological complications obtained during well drilling and also their systematization has been performed. The results of identification of geological reasons of failure to meet a drilling deadline are given. The experience of managed pressure drilling (MPD) technology is described. The chronology of drilling horizontal wells No. 161 and 169 is presented. The obtained experience clarified the idea of the geological structure of the carbonate-halogen sedimentary cover of the Early-Cambrian age. Lateral and vertical geological regularities of the occurrence of complications are determined. It make possible to upd ate the concept of wells drilling. The number of wells has been determined wh ere technological innovations must be applied in order to successfully achieve the se t geological tasks.

References

1. Shemin G.G., Geologiya i perspektivy neftegazonosnosti venda i nizhnego kembriya tsentral'nykh rayonov Sibirskoy platformy (Nepsko-Botuobinskaya, Baykitskaya anteklizy i Katangskaya sedlovina) (Geology and oil and gas potential Vendian and Lower Cambrian deposits of central regions of the Siberian Platform (Nepa-Botuoba, Baikit anteclise and Katanga saddle)): edited by Kashirtsev V.A., Novosibirsk: Publ. of SB RAS, 2007, 467 p.

2. Borges S., Dobrokhleb P.Yu., Krivolapov D.S. et al., Successful application of different managed pressure drilling techniques in Russia: Identification of challenges and selection of the optimum approach (In Russ.), SPE-192533-RU, 2018.

One of the key factors in oil production and field recovery increase is pressure maintaince system optimization. It is not a straightforward process even in relatively homogeneous well connected sands, but in reservoirs with a complex pore structures it become very hard to implement it and make in efficient. Carbonate deposits are characterized by a high degree of heterogeneity, both vertically and areal, and the lack of communication between the layers and faulted blocks. For the organization of an effective pressure maintenance system, information about the connectivity of the reservoir in the interwell space, data on its permeability distribution are crucial. The applicability of pulse code testing (PCT) was evaluated by pilot job and synthetic tests. One field pilot and 8 numerical tests were carried out. PCT provides reservoir boundaries, diffusivity and transmissibility of the connected part of the formation between wells and unit rate pressure impact without production deferment. Reservoir permeability and connected thickness can be calculated from diffusivity and transmissibility. It provides best candidates for conversion to injectors and wells with suspects to cross-flows for production logging and workovers. PCT results in synthetic tests are in good convergence of the generated reservoir properties and the data obtained by PCT, which indicates a high degree of reliability even in in a low permeable formations and in the presence of significant noise on the pressure curve. It is confirmed not only by matching the results of synthetic tests, but also by commercial implementation of the PCT for interwell analysis at the field.
References
1. Aslanyan A., Aslanyan I., Farakhova R., Application of multi-well pressure pulse-code testing for 3D model calibration, SPE-181555-MS, 2016.
2. Myakeshev N., Aslanyan A., Farakhova R., Gainutdinova L., Carbonate reservoir waterflood efficiency monitoring with cross-well pulse-code pressure testing, SPE-189258-MS, 2017.
3. Sabzabadi A., Masoudi R., Arsanti D. et al., Verifying local oil reserves using multi-well pressure pulse code testing, OTC-28601-MS, 2018.
4. Aslanyan A., Kovalenko I., Ilyasov I. et al., Waterflood study of high viscosity saturated reservoir with multiwell retrospective testing and cross-well pressure pulse-code testing, SPE-193712-MS, 2018.
5. Aslanyan A., Ganiev B., Lutfullin A. et al., Localization of the remaining reserves of r oilfield with pulse code pressure testing, SPE-196338-MS, 2019.
6. Taipova V., Aslanyan A., Aslanyan A., Aslanyan I et al., Verifying reserves opportunities with multi-well pressure pulse-code testing (In Russ.), SPE-187927-RU, 2017.
7. Aslanyan A., Asmadiyarov R., Kaeshkov I. et al., Multiwell deconvolution as important guideline to production optimisation: Western Siberia case study, IPTC-19566-MS, 2019.
8. Aslanyan A., Grishko F., Krichevsky V. et al., Assessing waterflood efficiency with deconvolution based multi-well retrospective test technique, SPE-195518-MS, 2019.
9. Aslanyan A., Gilfanov A., Gulyaev D. et al., Dynamic reservoir-pressure maintenance system study in carbonate reservoir with complicated pore structure by production analysis, production logging and well-testing, SPE-187776-MS, 2017.
10. Kaliyev B., Mutaliyev G., Aibazarov M. et al., Well spacing verification at gas condensate field using deconvolution driven long-term pressure and rate analysis, SPE-196925-MS, 2019.
11. Aslanyan A., Ganiev B., Lutfullin A. et al., Assessing efficiency of multiwell retrospective testing MRT in analysis of cross-well interference and prediction of formation and bottom- hole pressure dynamics, SPE-196839-MS, 2019.

Deposition of inorganic salt sediments is a sufficient challenge for successive exploration of oil and gas reservoirs in Eastern Siberia. The deposition process is known to be dependent on multiple parameters, which causes additional complications for its description. The observed sediments have a fairly diverse chemical composition. However, gypsum and halite are dominant. To predict the amount and composition of the sediment, as well as its distribution in the reservoir, it is necessary to know in detail the chemical compositions of the available aqueous solutions and their physical properties over the entire range of thermobaric conditions in the reservoir. The required information is not always readily available. However, the current level of development of digital chemistry and numerical methods for simulating a multiphase flow in porous media (a digital core approach) allows one to obtain the necessary information using numerical calculations.

This paper presents an integral approach to the problem. It includes numerical simulations of the miscibility of aqueous solutions using the OLI Studio package, confirmed by laboratory tests, and calculations of matrix porosity and permeability at reservoir conditions for different levels of salt deposition using a pore-scale hydrodynamic simulator DHD (CoreFlowTM) developed in Schlumberger Moscow Research center. Based on the simulation results, a method for construction of a composite hydrodynamic model in a reservoir simulator (ECLIPSE) is proposed. The model takes into account both precipitation and dissolution of inorganic salts. As the result of the study it was possible to make a conclusion about the root causes of salt deposition in the inter-well zone at one of the fields in Eastern Siberian: the mixing of injection waters with formation brine and changes of thermobaric conditions near injection and production wells, which characterize these zones as the most at risk of sediment formation.

The problem of salt deposition is relevant for many fields in Eastern Siberia, and, therefore, the proposed approach has good prospects to be widely used.

References

1. Chertovskikh E.O., Alekseev S.V., Problems of oil and gas production associated with gypsum depositing in the verkhnechonskoye oil and gas condensate field (In Russ.), SPE-171311-RU, 2014.

2. Vinogradov I.A., Zagorovskiy A.A., Bogachev K.Yu. et al., Laboratory and numerical study of the dissolution process of salinization clastic reservoirs (In Russ.), SPE-176630-RU, 2015.

3. Kashchavtsev V.E., Mishchenko I.T., Soleobrazovanie pri dobyche nefti (Salt formation in oil production), Moscow: Orbita-M Publ., 2004, 432 p.

4. Dinariev O.Yu., On the hydrodynamic description of a multicomponent multiphase mixture in narrow pores and thin layers (In Russ.), Prikladnaya matematika i mekhanika (PMM), 1995, V. 59, no. 5, pp. 776–783.

5. Dem'yanov A.Yu., Dinariev O.Yu., Evseev N.V., Osnovy metoda funktsionala plotnosti v gidrodinamike (Fundamentals of the density functional method in hydrodynamics), Moscow: Fizmatlit Publ., 2009, 312 p.

6. Koroteev D., Dinariev O., Evseev N. et al., Direct hydrodynamic simulation of multiphase flow in porous rock, Petrophysics, 2014, V. 55 (4), pp. 294-303

7. Andersen M.A., Digital core flow simulations accelerate evaluation of multiple recovery scenarios, World Oil, 2014, V. 98, pp. 50–56.

8. Shandrygin A., Shelepov V., Ramazanov R. et al., Mechanism of oil displacement during polymer flooding in porous media with micro-inhomogeneities (In Russ.), SPE-182037-RU, 2016.

9. Beletskaya A., Ivanov E., Stukan M. et al., Reactive flow modeling at pore scale, SPE-187805-MS, 2017.

10. MacDonald R.M., Geetan S.I., Klemin D., Hill B., Flow behavior from organic and mineral-hosted porosity systems — From pores to production, URTeC: 2902911, 2018.

11. Yakimchuk I., Evseev N., Korobkov D. et al., Permeability and porosity study of Achimov formation using digital core analysis, SPE-196928-MS, 2019.

12. Dinariev O., Evseev N., Klemin D., Density functional hydrodynamics in multiscale pore systems: chemical potential drive, Proceedings of E3S Web of Conferences, 2020, V.146, Article no. 01001, 10 p., https://doi.org/10.1051/e3sconf/202014601001.

13. Amaefule J.O. et al., Enhanced reservoir description: using core and log data to identify hydraulic (flow) units and predict permeability in un-cored intervals/wells, SPE-26436-MS, 1993, http://doi:10.2118/26436-MS.

14. Stolz A.-K., Graves R.M., Sensitivity study of flow unit definition by use of reservoir simulation, SPE-84277-MS, 2003.

15. Khormali A., Petrakov D.G., Farmanzade A.R., Prediction and inhibition of inorganic salt formation under static and dynamic conditions–Effect of pressure, temperature, and mixing ratio, Int. J. Technol., 2016, V. 7, no. 6, pp. 943–951.

In the paper are considered the features of hydrate control during the production of natural and associated petroleum gas from the Yaraktinskoye oil-gas-condensate field, located in the Ust-Kut district of the Irkutsk region. An analysis of the temperature and pressure modes of producing wells is given. It is noted that at the gas and gas condensate fields of Eastern Siberia there are some new features of the process of hydrate formation in the field systems. The hydrate formation conditions were calculated by the component composition of gas, taking into account the influence of methanol and formation saline water. It is shown that the process of hydrate formation is already possible in gas producing wells, which is due to the component composition of natural and associated petroleum gas (the presence of C2-C4 components, which easily form hydrates), high reservoir pressure (up to 25.4 MPa), and relatively low reservoir temperature (37 °C). Beforehand the hydrate formation in the wellbores was not observed during the development of gas condensate deposits in Western Siberia.

A technique for calculating the methanol consumption, taking into account high gas pressures and the possibility of producing formation water by the wells, has been developed. The risks of scaling in the wellbores due to halite precipitation when mixing concentrated methanol with formation water have been analyzed. It is noted that when using aqueous methanol solutions with methanol concentrations at the level of 60-65wt%, there are practically no risks of halite deposition. Technological calculations of the specific methanol consumption of and its aqueous solutions were carried out to prevent hydrate formation, taking into account the risks of scaling associated with high salinity of formation waters of the field. The results obtained make it possible to optimize the technology for hydrate inhibiting by methanol in the wellbores and gas-gathering systems of the Yaraktinskoye field.

References

1. Sabanchin I.V., Titov R.V., Petrakov A.M. et al., Physical simulation of gas injection at oil-gas-condensate fields of Eastern Siberia (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 6, pp. 92–96.

2. Elimova V.A., Rassoly Yaraktinskoy gruppy mestorozhdeniy (Brines of the Yarakta group of deposits), Collected papers “Stroenie litosfery i geodinamika” (The structure of the lithosphere and geodynamics), Proceedings of All-Russian youth conference XXVII, Irkutsk, 22–28th of May 2017, Irkutsk: Institut zemnoy kory SO RAN, 2017, pp. 86–87.

3. Burdakov D.A., Wolcott D., Water alternating gas pilot design and results: Yaraktinskiy field Eastern Siberia, SPE-196769-RU, 2019.

4. STO Gazprom 3.1-3-010-2008. Metodika rascheta norm raskhoda khimreagentov po gazodobyvayushchim predpriyatiyam OAO “GAZPROM” (Methodology for calculating the rates of consumption of chemicals for gas production enterprises of GAZPROM), Moscow: Publ. of Gazprom, 2009, 45 p.

5. Bukhgalter E.B., Metanol i ego ispol'zovanie v gazovoy promyshlennosti (Methanol and its use in the gas industry), Moscow Nedra, 1986, 238 p.

6. Istomin V.A., Kvon V.G., Preduprezhdenie i likvidatsiya gazovykh gidratov v sistemakh dobychi gaza (Prevention and elimination of gas hydrates in gas production systems), Moscow: Publ. of IRTs Gazprom, 2005, 556 p.

7.  Istomin V.A., Fedulov D.M., Minakov I.I. et al., Hydrates prevention in the bottom hole formation zone at high reservoir water salinity (In Russ.), Vesti gazovoy nauki. Problemy ekspluatatsii gazovykh, gazokondensatnykh i neftegazokondensatnykh mestorozhdeniy, 2013, no. 4 (15), pp. 15–21.

8. Istomin V., Kwon V., Kolushev N., Kulkov A., Prevention of gas hydrate formation at field conditions in Russia, Proceedings of 2nd Int. Conf. on Natural Gas Hydrates, June 2–6, 1996, Toulouse, France: Toulouse, 1996, pp. 399–406.

The formed organizational and technical system for the operation of a artificial lift is fundamental for effective oil production and success of the enterprise as a whole. In 2015, new technical management of Irkutsk Oil Company faced the need to change the approaches for process organization. The relatively short period of field exploitation and absence of traditions of its own for large-scale oil production in Eastern Siberia – all these required adaptation and implementation of set of actions in order to significantly increase the time between repairs and serviceability of downhole pumping equipment.

The paper presents the experience of Irkutsk Oil Company in its core asset, the Yaraktinskoye oil-gas-condensate field, as an example. The existing geological and technical conditions are presented; factors complicating oil production are described, as well as data on time between repairs and serviceability before implementing the set of measures to increase them. The article lists the organizational measures that were taken such as reconsideration of the organizational structure of the subdivisions responsible for the operation of the well stock, updating and expanding the stock of internal regulatory methodological documents, and measures for improving the personnel qualification. Some measures to improve durability were highlighted such as the use of thermal inserts in the cable lines of the ESP, the use of special fasteners, shafts and spline couplings of increased power, equipping the stock with control stations with a frequency drive and telemetric systems, etc. Special emphasis was put on the topic of operation in difficult conditions. Some measures to deal with asphaltene-resins-paraffin deposits, inorganic halite and gypsum deposits, the removal of mechanical impurities, and high gas-oil ratio of produced oil are listed. The introduction of advanced information products for monitoring and managing well stock operation is an essential part of the implemented activities. The implementation of the described set of measures made it possible to increase the time between repairs from 318 to 857 days.

Currently, scaling is the main factor complicating the development of the Yaraktinskoye oil-gas-condensate field. The paper provides general information on types of inorganic scales. Mainly they are halite, gypsum and calcium carbonate. The dynamics of the complicated well stock shows that the operation of most of them was complicated because of halite deposits. The share of production wells with halite scaling is currently 40%. Scaling occurs from the bottomhole formation zone to the wellhead which leads to a decrease in well productivity. The article presents data on the chemical composition of formation natural brines and describes the conditions contributory to scaling. Physicochemical analysis of scales obtained from pumping equipment was conducted. The methods for scales removal from downhole equipment and bottomhole formation zone are considered. It is discussed methods for prevention and technological solutions for dealing with halite deposits in production oil wells, equipped with electric centrifugal pumps, in Yaraktinskoye oil and gas condensate field. It is also described the methods of testing halite inhibitors in a saturated sodium chloride solution, as well as on actual formation water. The morphology of halite crystals before and after treatment with an inhibitor is described. The results of experimental-industrial application of halite inhibitor are given. The inhibitor was selected during the laboratory tests in order to protect downhole equipment in the production oil stock of the Yaraktinskoye oil-gas-condensate field. For inhibitor injection the technology of constant dosing the casing annulus were applied. There was gained good operating and scientific experience of using the inhibitor in wells, the operation of which was complicated by the formation of halite.

References

1. Voloshin A., Ragulin V., Nevyadovsky E., Ganiev I., Technical and economic strategy in the scale deposition management is an important factor in enhancement the efficiency of oil production (In Russ.), SPE 138066-RU, 2010.

2. Chertovskikh E.O., Kachin V.A., Karpikov A.V., Halite sedimentation under oil and gas extraction on Verkhnechonsk oil and gas-condensate field (In Russ.), Vestnik IrGTU, 2013, no. 5 (76), pp. 82–91.

3. Cheremisin A.N., Gorlanov A.A., Romanova D.D. et al., Problems of scaling when producing oil and gas in Yaraktinsky and Danilovsky deposits (In Russ.), Neftepromyslovoe delo, 2017, no. 10, pp. 45–51.

4.  Kashchavtsev V.E., Mishchenko I.T., Soleobrazovanie pri dobyche nefti (Salt formation in oil production), Moscow: Orbita-M Publ., 2004, 432 p.

5. Shablya V.V., Experience of Kogalymneftegas TPP  with salt-forming well stock (In Russ.), Inzhenernaya praktika, 2009, Pilot issue, pp. 24–28.

Oil production is inevitably accompanied by the formation of oil-water emulsions, and the main task in the oil field treatment is oil-water emulsions separation. Oil emulsions significantly affect the technological processes of separation, preliminary dehydration, demulsification and lead to the accumulation of an intermediate emulsion layer. This paper presents the research of oils of four fields of the Irkutsk Oil Company: Yaraktinskoye, Ichedinskoye, Machchobinskoye, and Bolshetirskoye. The physical and chemical properties of these are given. Based on the results of the IR spectra, the spectral coefficients of oil were calculated as the ratio of the optical densities of the corresponding absorption bands of the IR spectra; the group chemical composition was analyzed and the types of oil were determined. The influence of natural emulsifiers and mechanical impurities on the stability of oil emulsions has been investigated. High concentration of mineral salts in the produced water has a significant effect on the stabilization of oil emulsions in the East Siberian petroleum province; the produced waters have low pH values. The article also indicates the composition, physical and chemical characteristics of formation waters. The microphotographs of microscopic examination of the emulsion are presented. With the help of these microphotographs it was found that the composition of the emulsion includes a crystalline phase and the size of crystals is up to 300μ. The stability of dispersed systems was evaluated using the Lumifuge 116 analyzer (L.U.M. GmbH, Germany). Based on the results of the studies, the dependence of the emulsion phase boundary position on the time was found; it also made it possible to observe the kinetics of the process in real time mode. The studies carried out in Lumifuge device are the beginning of a creation of library of passing through profiles of dispersed systems for oilfield treatment use, which will make it possible to solve the problems associated with field development quickly and efficiently.

References

1. Chertovskikh E.O., Salikhov R.M., Alternative solutions to the problem of halite and gypsum formation during oil production in Eastern Siberia (In Russ.), Inzhenernaya praktika, 2017, no. 4.

2. Syunyaev Z.I., Safieva R.Z., Syunyaev R.Z., Neftyanye dispersnye sistemy (Oil dispersed systems), Moscow: Khimiya Publ., 1990, 226 p.

3. Unger F.G., Andreeva N.G., Fundamental'nye aspekty khimii nefti. Priroda smol i asfal'tenov (Fundamental aspects of petroleum chemistry. The nature of resins and asphaltenes), Novosibirsk: Nauka Publ., 1995, 185 p.

4. Tumanyan B.P., Nauchnye i prikladnye aspekty teorii neftyanykh dispersnykh sistem (Scientific and applied aspects of the theory of oil dispersed systems), Moscow: of Tekhnika Publ., 2000, 336 p.

5. Magomedsherifov N.I., Tarasov M.Yu., Stolbov I.V., Optimization of an oil treating process at booster pump system with preliminary water discharge unit (In Russ.), Neftyanoe khozyaĭstvo = Oil Industry, 2006, no. 12, pp. 95–96.

6. Pozdnyshev G.N., Stabilizatsiya i razrushenie neftyanykh emul’siy (Stabilization and destruction of oil emulsions), Moscow: Nedra Publ., 1982, 221 p.

7. Baĭbotaeva S.E., Moldabaeva G.Zh., Nadirov K.S., Scientific and technical foundations of methods for the destruction of water-oil emulsion during oil preparation (In Russ.), Vestnik Natsional'noĭ inzhenernoĭ akademii RK, 2018, no. 1 (67), pp. 46–51.

8. Frömer D., Lerche D., An experimental approach to the study of the sedimentation of dispersed particles in a centrifugal field, Arch. Appl. Mechanics, 2002, V. 72, pp. 85–95. 

9. Sobisch T., Lerche D., Application of a new separation analyser for the characterization of dispersions stabilized with clay derivates, Colloid Polym. Sci., 2000, V. 228, pp. 369–374. 

10. Mathies E., Sobisch T., Lerche D., A new method for rapid classification of demulsifiers to separate crude oil–water emulsions, Oil and Gas Chemistry, 2002. V. 1, pp. 485–491.

11. Syunyaev Z.I., Neftyanoy uglerod (Petroleum carbon), Moscow: Khimiya Publ., 1980, 270 p.

Current macroeconomic situation in the oil market (oil prices decrease, depletion of traditional reserves) poses challenges for oil and gas companies to improve the efficiency of capital and operating costs, the to increase speed of project implementation and their optionality depending on the volume and quality of incoming geological and technical information about development objects. It is particularly true for newly discovered fields in uninhabited regions of the Russian Federation.

The paper describes an up-to-date solution to decrease project implementation time and increase their mobility and variability based on the experience of Irkutsk Oil Company in the fields of the Irkutsk Region and the Republic of Sakha (Yakutia). The examples of the use of mobile and block-modular units for the development, treatment of associated petroleum gas, as well as their further modernization with additional information on fluids and well productivity were considered. The authors outlined 3 main types of units used by the Company. It is presented that units for the development of oil and gas fields can operate in a wide range of productivity: up to 1,400 m3/day of liquid and 950,000 m3/day of gas. At the same time, despite the small size and mobility of the equipment used, oil treatment can be done up to the first quality group in accordance with the current state standard. As one of the important advantages of such solutions, the authors outlined the possibility of a significant decrease in the content of sulfur compounds in oil by using chemical reagents. The article highlights Irkutsk Oil Company one of the first in Russia applied mobile units for the treatment and processing of associated petroleum gas with the release of dry stripping gas and a wide fraction of light hydrocarbons. Mobile and block-modular solutions allowed the Company to accelerate the setting of the fields into operation.

References

1. Sugaipov D.A., Batrashkin V.P., Khasanov M.M. et al., Basic principles of Gazprom Neft’s modular strategy for field infrastructure development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 12, pp. 68–71.

2. Dashevskiy A.V., Ustimchuk M.V., Dubrovin K.A. et al., Modern solutions for the infrastructure development of small fields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 12, pp. 124–125.

3. Kozhushkov I.P., Smirnov A.P., Block-modular method for the construction of oil and gas facilities (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 12, pp. 69–73.

4. Fedorenko V.D., Vlasov A.I., Yakovlev V.O. et al., Mobile modular systems for the production of commodity liquid product from the associated petroleum gas (In Russ.), PRONeft'. Professional'no o nefti, 2017, no. 4(6), pp. 64–69.

Consistent and steady power supply is fundamental to ensure oil and gas production in any region. It is particularly important for regions with no developed federal network infrastructure. Eastern Siberia is one of those regions. Here oil and gas producing enterprises have to make isolated power systems from scratch to ensure their own production activities.

The paper outlines the experience of Irkutsk Oil Company in making its own complex automated system of active and reactive power collective control (ARPCR) based on the power plants of Yaraktinskoye and Ichedinskoye fields. The present state of generation was analyzed. The paper presents the data on the stock of operating power units, special features of their operation and the gross installed capacity of the Company's power system. Promising solutions that were being actively implemented for the making of operational technological centers for the control of generating capacities were listed. The principles of the forming control center were described. One of the most important advantages is the ability to assess automatically the operating modes of multiunit power plants and connected networks without human involvement. The system being created is equipped with the ability to connect to collective control of any number of power units from each power plant from a single automated workstation. The paper highlighted an important principle of operation which was automatic collective control with proportional distribution of power consumption between power units. This control method allows a daily operation schedule in order to maintain the frequency and voltage of the generated electric current. The preprogrammed algorithms make it possible to influence the controls in minimum required time frames and to manage the power system effectively in normal and transient modes. It was highlighted that in the near future Irkutsk Oil Company is completing the implementation of the entire system.

The article discusses university and geophysical company cooperation under education financial limit conditions. Short story of high-school education forming in the Republic of Bashkortostan is shown. Special geophysics department in Ufa State Petroleum Technological University (launched in 1948) and the same in Bashkortostan State University (launched in 1909) form the base for education of mining geophysicist engineers. Probable problems and the reasons of engineer education deterioration such as lack of finance, different view at the intern-specialist professional skills, fast geophysical technologies connected with coming of international oilfield service companies to Russia, absence of pro-active training are uncovered. Results of school graduate interviews in different years about prestige (2003-2018) and quality (1997–2015) of Russian engineer education are shown. The contradictions between state standard of engineer education and real needs of potential employers because of modern industrial conditions are considered. The main is concentration of recent graduate on its possibility for self-dependent working under short adaptation time in contrast to newcomer-engineers. Quality and result of education process interconnection are shown as well as practice methods for its cooperation solving as follows: flexibility of theoretical and practice training courses, possibility of use of modern geophysical equipment in training process under real production conditions, cooperation of faculty members and specialist`s leaders for the personnel theoretical knowledge and practical skills. Methods of cooperation between universities and oilfield services companies for combined solving of cognitive and managerial tasks of professional education are revealed. This is the main problem, by authors’ opinion, for successful adaptation of recent graduate on business as well as clue for his future evolution. Specific examples of necessary skill set for logging geophysicist engineer and career growth diagram at the oilfield services company Bashneftegeofizika are provided. Professional and career possibilities of engineers and feedback with them universities are shown. The possibilities are provided by qualification upgrade at the company training center as well as special education departments, including if necessary, obtaining an academic degree. Noted, that getting of significant result is possible even under lack of education resource conditions if both partners – education establishment and oilfield services company – work for mutually profitable cooperation.

References

1. Kugel' S.A., Prestizh inzhenera v usloviyakh uskoreniya nauchno-tekhnicheskogo progressa (The prestige of an engineer amid accelerating scientific and technological progress), Leningrad: Znanie Publ., 1988, pp. 12–13.

2. Kul'kov E.V., What is the wide profile of a mechanical engineer (In Russ.), Vestnik vysshey shkoly, 1987, no. 1, pp. 39–44.

3. Skarzhinskiy M.I., Balandin I.Yu., Tyazhov A.I., Trudovoy potentsial sotsialisticheskogo obshchestva (Labor potential of a socialist society), Moscow: Ekonomika Publ., 1987, 37 p.

4. Nikitina N.Sh., Valeev M.A., Shcheglov P.E., Upravlenie kachestvom obrazovaniya. Sistemnyy podkhod (Quality management of education. Systems approach), Collected papers “Sistemy upravleniya kachestvom: proektirovanie, organizatsiya, metodologiya” (Quality management systems: design, organization, methodology), Proceedings of X symposium “Kvalimetriya cheloveka i obrazovaniya: metodologiya i praktika” (Human qualimetry and education: Methodology and practice), Part 4: edited by Selezneva N.A., Subetto A.I, Moscow: Publ. of Research Center for the Problems of Quality Training of Specialists, 2002, pp. 17–29.

5. Popova N.V., Key issues of contemporary educational policy and practice (In Russ.), Vysshee obrazovanie v Rossii, 2017, no. 10 (216), pp. 26–38.

The following the methodological basis is very important for new theoretical and practice activities of the petroleum industry, especially for exploration business process. The theory development in Earth science fields is part of high priorities of Rosneft Oil Company. Es a result of this corporate special attention, the exploration is currently very successful Rosneft’s activity by discovery of high quality new oil fields and also very efficient using of human and investments sources.

The article contains the explanation of the using the Method of analogy for large geological bodies as a bid depression, an orogen and a foothill area. Also the some terms are described according on the Method’s idea. The proposed concept is illustrated by real examples with similar geological features (geomorphological, genetical and etc.) and based on the process of the geological history identification. Tree postulates are argued.

1. It is possible to find the analogue for any of geological body.

2. Analogy has to be done for elements with similar hierarchical level and identical genesis.

3. It is necessary to do the geological time correlation during the matching process.

These postulates are based on conceptual matching pattern of Caspian and Gulf of Mexico depressions, the Verjoiansko-Kolimsky orogen system (Siberia) and the Canadian Rocky Mountings with foot hills areas, as petroleum basins. Also there is the comparative idea of matching Bagenov (Russia) and Vaca Muerta (Argentina) petroleum mother rock formations. Finally, it was explained the possibility of increasing efficiency of exploration at new areas by identification of the regional structure - analogue with good production results.

References

1. Miloserdova L.V., Matsera A.V., Samsonov Yu.V., Strukturnaya geologiya (Structural geology), Moscow: Neft' i gaz Publ., 2004, 537 p.

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

3. Hutton J., Theory of the Earth; or an investigation of the laws observable in composition, dissolution, and restoration of land upon the Glob, Transaction of the Royal Society of Edinburgh, 1788, V. 1, Part 2, pp. 209–304.

4. URL: https://daks.ccreservoirs.com/

5. Botvinovskaya O.A., Zagurenko A.G., Ganichev D.I., Compensating of petrophysical data deficiency using analogous reservoir information (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2009, no. 11, pp. 32–35.

6. Budennyy S.A., Analiz bol'shikh dannykh v neftegazovoy otrasli: bar'ery i vozmozhnosti (Big data analysis in the oil and gas industry: barriers and opportunities): SPE Technical Presentation, Moscow Section, 15.05.2018, URL: www.spe-moscow.org/

7. Vologin I.S., Islamov R.R., Nigmatullin F.N. et al., Methodology for selecting an analogous object for oil and gas reservoirs to geological and physical characteristics (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 12, pp. 124–127.

8. Austin J., Geologic history of Gulf of Mexico 2014 expedition operating area, URL: https://oceanexplorer.noaa.gov/okeanos/explorations/ex1402/background/geology/welcome.html

9. Nekrasov A.N., Geologiya i blagorodnometal'naya minerageniya Verkhoyano-Kolymskoy skladchatoy zony (Geology and noble metal minerageny of the Verkhoyansk-Kolyma fold zone): thesis of doctor of geological and mineralogical science, Moscow, 2017, 56 p.

10. Filatov N.I., Khain V.E., Development of the Verkhoyansk-Kolyma orogenic system as a result of interaction of adjacent continental and oceanic plates (In Russ.), Geotektonika = Geotectonics, 2008, no. 4, pp. 18–48.

11. Grinenko V.S., Baranov V.V., Verkhnepaleozoyskiy i mezozoyskiy etapy evolyutsii verkhoyanskogo terrigennogo kompleksa (zona perekhoda “Sibirskaya platforma – Verkhoyano-Kolymskaya skladchataya oblast'”) (Upper Paleozoic and Mesozoic stages of evolution of the Verkhoyansk terrigenous complex (transition zone "Siberian platform - Verkhoyansk-Kolyma fold region")), Proceedings of IX All-Russian scientific and practical conference “Geologiya i mineral'no-syr'evye resursy severo-vostoka Rossii” (Geology and mineral resources of the north-east of Russia), Part 2, Yakutsk, 2019, pp. 33–36.

12. Grigorenko V.S., Knyazev V.G., Devyatov V.P. et al., New data on the stratigraphy and history of the formation of the Upper Triassic – Jurassic sediments of the transition zone "Siberian platform – Verkhoyansk-Kolyma fold region” (In Russ.), Vestnik Goskomgeologii, 2012, no. 1, pp. 39–59.

13. McMechan M.E., Geology and  structure cross-section, Dawson Creek, British Columbia; Geological Survey of Canada, Map 1858A, scale 1:250 000, 1994.

14. Torsvik T.H., Cocks L.R.M., Earth history and palaeography, Cambridge University Press, 2017, 317 p.

15. Brod I.O., Vasil'ev V.G., Vysotskiy I.V. et al., Neftegazonosnye basseyny zemnogo shara (Oil and gas basins of the globe), Moscow: Nedra Publ., 1965, pp. 598.

16. Legerreta L., Villar H., Laffitte G. et al., Frontera exploratoria de la Argentina, Simposio de VI Congreso de Exploracion y  Desarrollo de Hidrocarburos, 2005, pp. 233–250.

17. Kalmykov G.A., Kiseleva N.L., Balushkina N.S., Tsvetkov D.L., Neftegazonosnye vysokouglerodistye tolshchi na granitse yury i mela (Oil and gas bearing high carbon strata on the Jurassic and Cretaceous boundary), Yaroslavl': Avers Plyus Publ., 2017, 330 p.

This article provides an overview of basin modeling results in the northwestern part of Tomsk region. In the research basin subsidence and thermal history reconstruction were investigated. Irregular distribution of heat flow in this area can be explained by rifting processes and influence of the massive granitoid intrusion. Many years of work allowed TomskNIPIneft to create a geochemical knowledge base of source rocks and types of oil in Western Siberia. As a result, it was possible to use generalized kinetic model for further investigation of the region. Vitrinite reflectance of coal and geochemical parameters of Bazhenov organic matter (4/1 MDBT и Тmax) were used for paleotemperature calibration. This analysis gave us a possibility to predict time and volumes of Bazhenov hydrocarbon generation and to allocate two generation sources of a different nature. In the research migration and accumulation modeling parameters were described. Based on the modeling results it was concluded that overpressure and automated hydraulic fracturing trigger primary migration. Two different methods of secondary migration calculation were compared. Despite some limitations, the results have shown a good match between modeled and real data (this is illustrated by accumulation map). Consequently, general plan of basin modeling of the West Siberian region was established, including stages and goals of oncoming project. According to the plan, this research is the result of the first (regional) stage of the basin modeling project. The results can be used separately as a tool for managing geological exploration, as well as a general information source for detailed modeling at the local scale.

References

1. Goncharov I.V., Samoylenko V.V., Oblasov N.V., Nosova S.V., Decrease of risk in oil exploration (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2006, no. 8, pp. 28–33.

2. Zakhryamina M.O., 3D modeling of the formation of hydrocarbon deposits in the junction zone of the Kaimysov arch and the Nyurolskaya depression (In Russ.), Interekspo Geo-Sibir', 2014, V. 2, no. 1, pp. 25–29.

3. Zakhryamina M.O., Basin modeling of hydrocarbon systems in the southwest of the Tomsk region (Nyurolka megadepression and adjacent territories) (In Russ.), Geologiya i mineral'no-syr'evye resursy Sibiri, 2016, no. 3, pp. 40–50.

4. Kosmacheva A.Yu., Zakhryamina M.O., Petroleum formation processes simulation of Chkalov field, Tomsk area (In Russ.),  Neftegazovaya geologiya. Teoriya i praktika, 2017, V. 12, no. 1.

5. Kontorovich V.A., Belyaev S.Yu., Kontorovich A.E. et al., Tectonic structure and history of evolution of the west Siberian geosyneclise in the Mesozoic and Cenozoic (In Russ.), Geologiya i geofizika, 2001, V. 42, no. 11–12, pp. 1832–1845.

6. Kontorovich V.A., Tektonika i neftegazonosnost' mezozoysko-kaynozoyskikh otlozheniy yugo-vostochnykh rayonov Zapadnoy Sibiri (Tectonics and oil and gas potential of the Mesozoic-Cenozoic deposits in southeastern areas of Western Siberia), Novosibirsk: Publ. of SB RAS, Branch "Geo", 2002, 253 p.

7. Neruchev V.G., Vassoevich N.B., Lopatin N.V., O shkale katageneza v svyazi s nefteobrazovaniem (On the scale of catagenesis in connection with oil and gas formation), In: Gryuchie iskopaemye (Fossil fuels): edited by Kontorovich, Moscow: Nauka Publ., 1976, pp. 47–62.

8. Goncharov I.V., Samoylenko V.V., Oblasov N.V., Fadeeva  S.V., Catagenesis of organic matter Bazhenov Formation rocks in the south-east of West Siberia (Tomsk region) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 10, pp. 32–37.

9. Patent no. 2261438 RF, MPK7 G 01 N 30/02, G 01 V 9/00, Method of determining ripened oil-source rocks, Inventors: Goncharov I.V., Samoylenko V.V., Nosova S.V., Oblasov N.V.

10.  Patent RU 2 634 254 C1, Method for determining mature coal-bearing oil-source rocks and specifying their catagenesis, Inventors: Oblasov N.V., Goncharov I.V., Samoylenko V.V., Fadeeva S.V.

11. Kashapov R.S., Goncharov I.V., Oblasov N.V. et al., Organic matter of Bazhenov formations: new approach to kinetic studies (In Russ.), Geologiya nefti i gaza, 2020, no. 3, pp. 51–59, DOI: 10.31087/0016-7894-2020-3-51-59.

12. Pepper A.S., Corvi P.J., Simple kinetic models of petroleum formation. Part I. Oil and gas generation from kerogen, Marine and Petroleum Geology, 1995, V. 12, pp. 291–319.

13. PetroMod 2019.1. User Guide.

14. Hantschel T., Kauerauf A.I., Fundamentals of basin and petroleum systems modeling, Berlin: Springer, 2009, 476 p.

Nowadays, complicated due to the increased content of clay matter structure reservoirs have been involved in the development and operation by Rosneft Oil Company. Sometimes widely used in laboratory practice (capillarimetry, routine petrophysical studies) core analysis methods treatment faces a number of significant difficulties and limitations including in extreme cases the complete impossibility of their using in the case of weakly consolidated, highly clay and oil source rocks. It is obvious that the complex terrigenous reservoirs core samples researching process faces certain difficulties, such as partial or complete destruction of samples under repeated exposure, violation of the integrity of the pore space, etc. Integration of research methods in this case is problematic. At the same time, even under such non-trivial conditions, the existing and currently developing method of laboratory NMR-relaxometry is quite capable to solving the problems of determining both the standard set of filtration – reservoir properties and specific ones-determining capillary-bound, structural (bound in clays) and free fluid, phase composition of the saturating fluid and the parameters associated with the above.

The employees of Rosneft together with employees of the laboratory complex Rosneft-NTC LLC (a subsidiary of Rosneft Oil Company) considered the possibility of using the NMR-relaxometry method for the rapid assessment of clay content of terrigenous rocks. Based on the results obtained, it can be concluded that a single experiment is applicable by the method of NMR-relaxometry where along with the determination of the above petrophysical parameters, the clay content of the rocks is estimated without additional involvement of particle size analysis data, which helps to reduce time and effort required to laboratory studies.

References

1. Metodicheskie rekomendatsii po issledovaniyu porod-kollektorov nefti i gaza fizicheskimi i petrograficheskimi metodami (Guidelines for the research of oil and gas reservoir rocks by physical and petrographic methods), Moscow: Publ. of VNIGNI, 1978, 381 p.

2. Coates G.R., Xiao L., Prammer M.G., NMR logging principles and applications, Houston: Hullibarton Energy Services, 1999, 335 p.

3.  Dzhafarov I.S., Syngaevskiy P.E., Khafizov S.F., Primenenie metoda yaderno-magnitnogo rezonansa dlya kharakteristik sostava i raspredeleniya plastovykh flyuidov (Application of nuclear magnetic resonance to determine the composition and distribution of reservoir fluids), Moscow: Khimiya Publ., 2002, 439 p.

4. Omel'yanyuk M.V., Pakhlyan I.A., Rogozin A.A., Justification of the combined technology for enhanced oil recovery in case of Maikop sediments (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 9, pp. 114 - 116.

5. Shumskayte M.Y., Opredelenie petrofizicheskikh parametrov peschano-glinistykh obraztsov kerna i tipizatsiya plastovykh flyuidov metodom YaMR-relaksometrii (Determination of petrophysical parameters of sandy-clayey core samples and typification of formation fluids by NMR-relaxometry): thesis of candidate of technical science, Novosibirsk, 2017.

6. Kharisov R.F., NMR relaxometry as a method for studying fluid filtration in a pore medium based on the results of assessing the type and volume of clay minerals (In Russ.), Vestnik nedropol'zovatelya Khanty-Mansiyskogo AO, 2014, V. 26, URL: http://www.oilnews.ru/26-26/yamr-relaksometriya-kak-metod-izucheniya-filtracii-flyuida-v-porovoj-sre...

7. Tugarova M.A., Porody-kollektory: Svoystva, petrograficheskie priznaki, klassifikatsii (Reservoir rocks: Properties, petrographic features, classifications), St. Petersburg: Publ. of  SPbSU, 2004, 36 p.

Despite the availability of modern remote technologies and geological and geophysical methods for studying the Earth, the well remains the only tool for objective study of the earth's crust and a channel for extracting deep minerals. Deep and ultra-deep wells in Russia and in some foreign countries typically are drilled to perform complex regional geological and geophysical studies, including the study of the geological structure of major geostructural interpretation of the elements of the earth's crust, determining the general laws of accumulation, as well as to study geological-geophysical characteristics of the section and assessment of prospects of ore and petroleum potential and identify promising areas for prospecting. In order to select the most promising areas for regional exploration, complex geological and geophysical, technical and technological studies and special work under complex thermobaric conditions and in depths not previously explored should be carried out in reference and parametric wells. In this regard, there are a number of special requirements for the well, its wiring technology, drilling fluids, cement mortar-stone, as well as in general - the reliability and manufacturability of the design of the created object.

The article discusses the issues of creating optimal structures and high-quality support of wells when cementing casing columns of various sizes and purposes for solving problems of support-parametric drilling. The features of their cementing are considered, the compositions of grouting solutions and process fluids used for cementing casing columns in complex thermobaric conditions are analyzed. Many years of experience in fixing casing strings in complex, previously undeveloped depths, based on technological, analytical and research work, is the most important scientific and technical result, the replication of which has significantly improved the quality of design and implementation of structures of deep wells for various purposes in extreme, previously unknown, conditions.

References

1. Kurbanov Ya.M. et al., Features of the application of drilling fluids for parametric ultradeep well SG-7 targeting (In Russ.), Stroitel'stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2005, no. 1, pp. 42–45.

2. Kurbanov Ya.M., Zaykovskaya T.V., Cheremisina N.A., Some specific features of control of drilling fluids’ rheological properties when drilling En-Yakhinsky super-deep parametric well SG-7 (In Russ.), Stroitel'stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2015, no. 7, pp. 13–19.

3. Bulatov A.I., Makarenko P.P., Budnikov V.F., Basarygin Yu.M., Teoriya i praktika zakanchivaniya skvazhin (Theory and practice of well completion): edited by Bulatov A.I., Part 5, Moscow: Nedra Publ., 1998, Parts 2, 4.

4. RD 41-014306-98, Instruktsiya po povysheniyu nadezhnosti i dolgovechnosti krepi glubokikh i sverkhglubokikh skvazhin (Instructions for improving the reliability and durability of the support for deep and ultra-deep wells): edited by Kurbanov Ya.M., Dmitriev V.L., Khakhaev B.N., Oksenoyd E.Ya., Moscow: Publ. of Ministry of Natural Resources of the Russian Federation RF, 1998, 58 p.

5. Kurbanov Ya.M., Khakhaev B.N., Angelopulo O.K., Actual problems of creating support for deep and superdeep wells (In Russ.), Neftegazovye tekhnologii, 2000, no. 2, pp. 6–9.

6. Ekhlakov Yu.A., Gorbachev V.I., Karaseva T.V. et al., Geologicheskoe stroenie i neftegazonosnost' glubokozalegayushchikh otlozheniy Timano-Pecherskoy NGP  (Geological structure and oil and gas content of deep-seated deposits of the Timan-Pechora province), Perm'.: Publ. of KamNIIKIGS, 2000, 330 p.

7. Tyumenskaya sverkhglubokaya skvazhina (interval 0-7502m). Rezul'taty bureniya i issledovaniya (Tyumen superdeep well (interval 0-7502 m). Drilling and survey results), Proceedings of scientific meeting "Scientific drilling in Russia", 21-23 February 1995, Perm': Publ. of KamNIIKIGS, 1996, 376 p.

8. Oksenoyd E.Ya., Gurak V.M., Pod"yacheva N.A., Opyt krepleniya Tyumenskoy SG-6 194 mm khvostovikom pri anomal'nykh PT-usloviyakh (Experience of fastening the Tyumen SG-6 with a 194 mm liner under abnormal PT conditions), Perm': Publ. of KamNIIKIGS, 2001, 480 p.

9. Metodicheskie ukazaniya po vyboru konstruktsiy neftyanykh i gazovykh skvazhin, proektiruemykh dlya bureniya na razvedochnykh i ekspluatatsionnykh ploshchadyakh (Guidelines for the selection of structures for oil and gas wells designed for drilling at exploration and production areas), Moscow: Publ. of Minnefteprom, 1973, 10 p.

10. Herman Z., Printsipy proektirovaniya konstruktsiy glubokikh skvazhin (Deep well design principles), Pyatigorsk: Publ. of SevKavNIPIneft', 1977.

11. RD-39-00147-001-767-2000. Instruktsiya po krepleniyu neftyanykh i gazovykh skvazhin (Instructions for oil and gas wells cementing), Moscow, 2000, 270 p.

12. Bliznyukov V.Yu., Design of rational designs for ultra-deep wells (In Russ.), Stroitel'stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2003, no. 2, pp. 14–21.

13. Kurbanov Ya.M., Khakhaev B.N., Aliev R.M., Danyushevskiy V.S., Tamponazhnye rastvory dlya glubokikh neftegazovykh skvazhin (Grouting slurries for deep oil and gas wells), Moscow: Nedra Publ., 1996, 239 p.

14. Khakhaev B.N., Kurbanov Ya.M., Oksenoyd E.Ya. et al., Features of reverse cementing of a technical casing string with a diameter of 273 mm at Yen-Yakhinskaya SG-7 (In Russ.), Razvedka i okhrana nedr, 2003, no. 6, pp. 20–22.

15. Kurbanov Ya.M.,  Khayrullin A.A., Some features of well cementing at low rates of replacement (In Russ.), Burenie, 2001, no. 11, pp. 14–17. 

16. Kurbanov Ya.M.,  Cheremisina N.A., Analysis of technical solutions to prevent the flow of formation fluids into the annulus of the well during the waiting period for cement solidification (WOC) (In Russ.), Izvestiya vuzov. Neft' i gaz, 2019, no. 5, pp. 64–71.

17. Karimov N.Kh., Agzamov F.A., Kurbanov Ya.M., Tamponazhnyy material dlya krepleniya glubokikh i sverkhglubokikh skvazhin (Backfill material for casing deep and superdeep wells), Proceedings of  All-Russian meeting “Burenie glubokikh i sverkhglubokikh parametricheskikh skvazhin” (Drilling deep and ultra-deep parametric wells), Yaroslavl', 2001, pp. 83–86.

18. Kurbanov Ya.M., Zaykovskaya T.V., Cheremisina N.A. et al., Drilling of parametric borehole on the Zheldonskaya area under conditions of diverse lithological and stratigraphic section and uncertainty of geological and technical conditions (In Russ.), Neftyanoe khozyaystvo=Oil Industry, 2016, no. 9, pp. 39–43.

The Mongi field is the largest on Sakhalin island, which has been developed since the early 1970s to the present. Production of this field is currently uneven: for example, the oil recovery factor (ORF) in the southern part of the field is on average higher than 0.5, which is associated with a favorable hydrogeological condition. The reverse situation is presented in the northern part of the field, where the average ORF is less than 0.2, which is a consequence of the weak influence of aquifer, significant compaction of rocks and deterioration of the reservoir properties. Complicated development conditions, such as a high degree of development and water-cut, as well as an uneven reduction in reservoir pressure dictate the conditions for the formation of a strategy for additional development of reserves. Detailed study of disjunctive dislocations of the Mongi filed is the main tool for the successful implementation of Wellwork programs and effective development of residual recoverable reserves, since they directly affect the behavior of reservoir pressure. Field data, results of research on production drilling indicate secondary processes occurring in reservoirs during development. The decrease in reservoir properties based on the results of well testing, low starting flow rates, lack of inflow during development, and the results of reservoir simulation confirm the process of rock compaction due to a critical decrease in reservoir pressure. The obtained data were used in forming the strategy for optimization and development of the development system at Mongi field. The authors offer recommendations for improving the efficiency of reservoir pressure maintenance system, substantiate the relevance of hydraulic fracturing, and form the concept of identifying sweet spots in the formation of the production drilling program.

References

1. Khaliulin R.R., Zakirov S.N., Features of the Mongi oil-gas-condensate field development (Sakhalin Island) (In Russ.), Neftyanoe khozyaystvo = Oil Industry,  2020, no. 8, pp. 30–33, DOI: 10.24887/0028-2448-2020-8-30-33.

2. Ganaeva M.R., Sukhodanova S.S., Khaliulin Ruslan R., Khaliulin Rustam R., Sakhalin offshore oilfield hydraulic fracturing optimization by building a 3D geomechanical model (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 6, pp. 108–111.

3. Zakirov S.N., Mukhametzyanov R.N., Dzhafarov I.S. et al., Vertikal'no-lateral'noe zavodnenie na zavershayushchey stadii razrabotki (Vertical-lateral flooding at the final stage of development), Industry meeting materials “Razrabotka mestorozhdeniy v zavershayushchey stadii” (Field development in the final stage), 2007, 90 p.

4.  Zakirov S.N., Indrupskiy I.M., Zakirov E.S. et al., Novye printsipy i tekhnologii razrabotki mestorozhdeniy nefti i gaza (The new principles and technologies of oil and gas fields development), Part 2, Moscow - Izhevsk: Publ. of Institute of the computer science, 2009, 484 p.

Reservoir and production engineering processes involve a number of components applied to monitor and plan such parameters during oil and gas fields development as oil production profile calculation and ultimately recoverable reserves estimation. Field-statistical models such as displacement curve and decline curve analysis models are wildly used to forecast production performance and estimate reserves. As compared to decline curve analysis, displacement curve analysis provides a better result in production forecasting in waterflooded oil reservoirs since, apart from oil production, they also take into account liquid and water production. However, both methods are deterministic i.e. make no allowance for uncertainty in calculations that can result in failure to achieve planned production performance. In order to solve the problem of uncertainty quantification and risks assessment in production forecasts and ultimately recoverable reserves estimates, foreign scientists have applied methods of machine learning with traditional methods of oil and gas production forecasting.

This research for the first time applies such advanced machine learning methods as Bayes theorem and Markov Chain Monte Carlo simulation with integral displacement curve models for quantitative assessment of risks and uncertainty in the production forecasts and estimates of ultimately recoverable reserves. Developed methodology of probabilistic production forecasting yields to different probabilistic scenarios of production profiles and reserves estimates, accuracy improvement of the forecasts, and, as a consequent, increase in quality of decision making. In the framework of this study, hindcast has been carried out based on the history of 130 production wells of two waterflooded oil fields in order to assess reliability of the developed probabilistic methodology of production forecasting. In addition, the comparative study of developed method and foreign probabilistic methodology has been conducted on the basis of hindcast results.

References

1. Sazonov B.F., Sovershenstvovanie tekhnologii razrabotki neftyanykh mestorozhdeniy pri vodonapornom rezhime (Perfection of technology of development of oil deposits at a water-pressure mode), Moscow: Nedra Publ., 1973, 238 р.

2. Maksimov M.I., The method for calculating recoverable oil in the final stage of exploitation of oil reservoirs under oil displacement by water (In Russ.), Geologiya nefti i gaza, 1959, no. 3, pp. 42–47.

3. Burger J.G., Combarnous M., Thermal methods for hydrocarbon production, Journal Of Oil & Gas Science and Technology, IFP, 1975, V. 30, pp. 551–578.

4. Nazarov S.N., Sipachev N.V., Technique of forecasting technological indicators at the late stage of development of oil deposits (In Russ.), Izvestiya vuzov. Neft' i gaz, 1972, no. 10, pp. 41–46.

5. Sipachev N.V., Posevich A.G., Nazarov S.A. et al., Estimation of recoverable oil reserves based on integral curves of oil and water extraction (In Russ.), Azerbaydzhanskoe neftyanoe khozyaystvo, 1972, no. 5, pp. 20–21.

6. Gaysin D.K., Metod prognoza tekhnologicheskikh pokazateley i nefteotdachi plastov po promyslovym dannym v pozdney stadii razrabotki (Method for predicting technological indicators and oil recovery from reservoir data at a late stage of development), Proceedings of BashNIPIneft', 1986, V. 74, pp. 128–137.

7. Pirverdyan A.M., Nikitin P.I., Listengarten L.B., Danelyan M.G., On the forecast of oil and associated water production in the development of bedded heterogeneous reservoirs (In Russ.), Azerbaydzhanskoe neftyanoe khozyaystvo, 1970, no. 11.

8. Kambarov G.S., Almamedov D. G., Makhmudova T.Yu., Determining the initial recoverable reserves of oilfield (In Russ.), Azerbaydzhanskoe neftyanoe khozyaystvo, 1974, no. 3, pp. 22–24.

9. Abyzbaev I.I., Nasyrov G.T., On the factors affecting oil recovery in oil-water zones (In Russ.), Geologiya nefti i gaza, 1975, no. 2, pp. 60–63.

10. Gong X., Gonzalez R., McVay D., Bayesian probabilistic decline curve analysis quantifies shale gas reserves uncertainty, SPE-147588-MS, 2011, DOI: 10.2118/147588-ms.

11. Xie J., Efendiev Y., Datta-Gupta A., Uncertainty quantification in history matching of channelized reservoirs using Markov chain level set approaches,

SPE-141811-MS, 2011, DOI: 10.2118/141811-MS.

12. Liu C,  McVay D.A., Continuous reservoir simulation model updating and forecasting using a Markov chain Monte Carlo method, SPE-119197-MS, 2009.

13. Zolotukhin A.B., Frick T.P., A mobility driven fingering approach to the field-scale simulation of oil recovery, SPE-27017-MS, 1994, DOI: 10.2118/27017-MS.

14. Nazarenko M., Probabilistic production forecasting and reserves estimation in waterflooded oil reservoirs, SPE-192167-MS, 2018.

15. RD 153-39.0-110-01. Metodicheskie ukazaniya po geologo-promyslovomu analizu razrabotki neftyanykh i gazoneftyanykh mestorozhdeniy (Methodical instructions on geological and field analysis of oil and gas fields development), Moscow: Publ. of Ekspertneftegaz, 2002, 119 p.

Vietsovpetro main line of business includes research activities, geological exploration, field development, production, gathering and treatment of oil, gas and condensate at the South of SRV continental shelf. Recently, the consistent downtrend of reserves quality is observed, which leads to necessity of searching the new development technologies and methods, as well as improving the existing ones. Hydraulic fracturing is one of the most applicable and effective method for low permeable highly dissected reservoirs, and it impacts both on the current production rates and ultimate recovery. Deep penetration fracturing takes effect on the bottom-hole area and uninvaded zones resulting in improving the sweeping and recovery efficiency.

The article covers the main results of implementing hydrofracturing in low permeable highly dissected Oligocene reservoirs of Vietnam offshore fields, as well as the implementation and planning features of such well intervention activities based on the obtained experience. Implementation of hydrofracturing in dissected and lithologically heterogeneous reservoirs results in development of hydrodynamically isolated undrilled and non-perforated interlayers and lenses. Replication of the best practice helps bringing the new blocks and reservoirs under development, from which the production considered ineffective or low-margin without hydraulic fracturing. New technologies implementation helps improving the designs adaptivity and broadens the hydrofracturing application criteria.

References

1. Utochnennaya tekhnologicheskaya skhema razrabotki i obustroystva mestorozhdeniya Belyy Tigr (Refined technological scheme for the development and construction of the White Tiger field), Vungtau, 2018

2. Ivanov A.N., Zyong Zan' Lam, Vasil'ev V.A., Enhanced recovery techniques in the white tiger oilfield: analysis of the effective use (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2008, no. 1, pp. 76-78.

3. Economides M., Oligney R., Valko P., Unified fracture design. Bridging the gap between theory and practice, Orsa Press, Alvin, Texas, 2002, 262 p.

4. Sadovnikov A.A. Klevtsov A.S. Kozyk S.S., Exploration of the Oligocene dense sandstone reservoirs potential of Nam Con Son shelf basin (In Russ.), Neftyanoe khozyaystvo = Oil Industry,  2018, no. 11, pp. 88–90.

5.  Kosad Ch., The choice of perforation strategy (In Russ.), Neftegazovoe obozrenie, 1998, V. 3, no. 1, pp. 34–51.

The paper considers the problem of isothermal filtration of a binary hydrocarbon mixture in a porous medium, taking into account capillary pressure and the presence of retrograde regions of the phase diagram. The thermodynamic properties of the model mixture were calculated using the Peng – Robinson equations of state. The Lorentz – Bray – Clark relations were used to determine the viscosity of the phases, and the Gillespie – Lerberg equation was used to determine the chemical potentials. The functions of the relative phase permeability were specified in the form of empirical formulas of Chen Chzhun Xiang. The system of differential equations describing the modeled process was solved by the finite element method in the FlexPDE environment. It is shown that for given thermobaric conditions for filtering a binary mixture through a porous medium, time-varying changes in saturation, mixture composition, and mass flow rate of the liquid and vapor phases at the exit of the experimental model are possible. For the case of filtration of a model gas-condensate mixture of methane - butane, the problem was solved in an equilibrium and non-equilibrium formulation, and in both cases, the calculation results confirm the assumption about the cyclic formation of a liquid plug and its movement inside the simulated section. It is shown that taking into account nonequilibrium leads to a change in the pressure field along the filtration path, the amplitude and shape of the resulting self-oscillations in the flow rate of the vapor and liquid phases. These features must be taken into account when interpreting unsteady regimes of real (nonequilibrium) flows of reservoir fluids in the bottomhole formation zone. The proposed model can be used to assess the effectiveness of technologies for increasing the flow rate of gas condensate wells by affecting the bottomhole formation zone, as well as when calculating the flow rate of a well, taking into account the possibility of unsteady filtration modes.

References

1. Mitlin V.S., Self-oscillatory flow regimes of two-phase multicomponent mixtures through porous media (In Russ.), Doklady AN SSSR, 1987, V. 296, pp. 1323–1327.

2. Makeev B.V., Mitlin V.S., Self-oscillation in distributed systems: phase change filtering (In Russ.), Doklady AN SSSR, 1990, V. 310, no. 6, pp. 1315–1319.

3. Zaychenko V.M., Torchinskiy V.M., Sokotushchenko V.N., Kolebaniya i volny v gazokondensatnykh sistemakh (Oscillations and waves in gas condensate systems), Moscow: Publ. of Joint Institute for High Temperatures of the Russian Academy of Sciences, 2017, 146 p., ISBN 978-5-9500112-1-4.

4. Grigor'ev B.A., Zaychenko V.M., Molchanov D.A. et al., Math simulation of gas condensate mixture isothermal filtering for different flow patterns (In Russ.), Vesti gazovoy nauki. Aktual'nye voprosy issledovaniy plastovykh sistem mestorozhdeniy uglevodorodov, 2016, V. 28, no. 4, pp. 37–40.

5. Kachalov V.V., Molchanov D.A., Zaichenko V.M., Sokotushchenko V.N., Mathematical modeling of gas-condensate mixture filtration in porous media taking into account non-equilibrium of phase transitions, J. Phys.: Conf. Ser., 2016, V. 774, DOI:10.1088/1742-6596/774/1/012043.

6. Zemlyanaya E.V., Kachalov V.V., Volokhova A.V. et al., Numerical investigation of the gas-condensate mixture flow in a porous medium (In Russ.), Zhurnal komp'yuternye issledovaniya i modelirovanie, 2018, V. 10, no. 2, pp. 209–219.

7. Sokotushchenko V.N., Mathematical and experimental modeling filtration processes of hydrocarbons in a gas condensate reservoir (In Russ.), Vestnik Mezhdunarodnogo universiteta prirody, obshchestva i cheloveka “Dubna”. Ser. Estestvennye i inzhenernye nauki, 2018, no. 1 (38), pp. 32–38.

8. Basniev K.S., Kochina I.N., Maksimov V.M., Podzemnaya gidromekhanika (Underground hydromechanics), Moscow: Nedra Publ., 1993, 416 p.

9. PVTi referens manual, Schlumberger, 2009.1.

10. Peng D.Y., Robinson D.B., A new two-constant equation of state, Industrial and Engineering Chemistry Fundamentals, 1976, V. 15, pp. 59–64.

11. Krichevskiy I.R., Ponyatiya i osnovy termodinamiki (Thermodynamics concepts and basics), Moscow: Khimiya Publ., 1970, 440 p.

12. Gubaydullin D.A., Sadovnikov R.V., Nikiforov G.A., Chislennoe modelirovanie dvukhfaznoy fil'tratsii v peremennykh skorost' – nasyshchennost' (Numerical modeling of two-phase filtration in variables velocity – saturation), Collected papers “Aktual'nye problemy mekhaniki sploshnoy sredy. K 20-letiyu IMM KazNTs RAN” (Actual problems of continuum mechanics. To the 20th anniversary of Institute of Mechanics and Engineering), Kazan': Publ. of Institute of Mechanics and Engineering, 2011, pp. 161–180.

Along with salt deposition at pumping stations, hydrate plugs become one of the main complicating factors in oil and gas production. To date, the problem of hydrate formation in oil wells in Surgutneftegas PJSC is becoming more and more urgent due to the growth of low-capacity wells. The flow of liquid raised from the reservoir does not provide sufficient heating of the production column in the zone of permafrost. Predicting the formation of hydrate formation conditions at the moment does not allow to completely avoiding this complication. The most effective method for eliminating hydrate plugs is a continuous pipe complex. However, when working on low-yield wells, the payback period of this measure is quite long and does not guarantee the absence of complications even for the payback period. In addition to the continuous pipe, various other methods offered on the market were used, but a positive result was not achieved.

In this regard, the Company has tested and successfully used the method described in the article to get rid of the hydrate plug. The method is cost-effective, and sometimes faster in achieving the result, taking into account the expectations of the continuous pipe complex according to the traffic schedule. The effectiveness and time to achieve a positive result by applying the method described below directly depends on the intensity of its application, as well as the time of existence of the hydrate in the well. The hydrate plug breaks down faster in wells with a large gas factor, which is explained by the accumulation of a large amount of gas. The method has been successfully applied since 2018 and can be applied to any fields due to its versatility.

References

1. Tsiku Yu.K., Starikov N.V., Samarin S.Yu., Oslozhneniya, voznikayushchie pri ekspluatatsii periodicheskogo fonda skvazhin i puti ikh resheniya (Complications arising from the operation of a periodic well stock and ways to solve them), Collected papers “Stat'i dlya inzhenerov PAO “Surgutneftegaz” (Articles for engineers of Surgutneftegas PJSC), 2019, no. 11, pp. 15–16.

2. Razumov A.I., Chebataev G.G., Filev K.A., Gidratoobrazovanie v zatrubnom prostranstve neftyanykh skvazhin NGDU “Surgutneft'”. Opyt likvidatsii (Hydrate formation in the annular space of oil wells of NGDU “Surgutneft”. Elimination experience), Collected papers “Stat'i dlya inzhenerov PAO “Surgutneftegaz” (Articles for engineers of Surgutneftegas PJSC), 2019, no. 11, pp. 24–25.

Pipeline pulling into the borehole is the final and most important stage in the construction of the transition by the method of horizontal directional drilling. Analysis of changes in the values of traction forces implemented in the process of dragging the pipeline shows that the values of traction forces implemented in practice do not correspond to the calculated ones. This is due to the fact that the work spent on carrying out the process of dragging the pipeline into the well consists of the work spent on overcoming the influence of the pipeline weight, as well as on the elastic deformation of the pipeline when overcoming curved sections of the borehole and obstacles formed during the expansion of the pilot borehole. The most significant influence on the amount of pulling forces of the pipeline is exerted by the elastic-deformative properties of the pipeline being dragged; the limiting factor for the pipeline passage in the constructed well is the ability of the pipeline to deform when overcoming the curved intervals of the underwater transition profile and various obstacles along the borehole. Reducing the cost of effort for elastic deformation of the pipeline being dragged leads to a multiple decrease in the values of the realized traction forces of dragging the pipeline during the construction of an underwater passage. Therefore, the geometric parameters of the constructed well and, as a result, the correctly selected technology of its construction, which provides the required geometric parameters of the well, play a crucial role in dragging the pipeline.
References
1. Sharafutdinov Z.Z., Parizher V.I., Sorokin D.N. et al., Stroitel'stvo perekhodov magistral'nykh truboprovodov cherez estestvennye i iskusstvennye prepyatstviya (Construction of crossings of trunk pipelines through natural and artificial obstacles), Novosibirsk: Nauka Publ., 2013, 339 p.
2. Sal'nikov A.V., Zorin V.P., Aginey R.V., Metody stroitel'stva podvodnykh perekhodov gazonefteprovodov na rekakh Pechorskogo basseyna (Construction methods for underwater crossings of gas and oil pipelines on the rivers of the Pechora basin), Ukhta: Publ. USTU, 2008, 108 p.
3. Kharitonov V.A., Bakhareva N.V., Organizatsiya i tekhnologiya stroitel'stva truboprovodov metodom gorizontal'no-napravlennogo bureniya (Organization and technology of construction of pipelines using horizontal directional drilling), Moscow: ASV Publ., 2011, 344 p.
4. Sharafutdinov Z.Z., Komarov A.I., Golofast S.L., Pilot drill hole reaming in construction of trunk pipelines’ submerged crossings (In Russ.), Truboprovodnyy transport: teoriya i praktika, 2016, no. 5(57), pp. 32–40.
5. Sharafutdinov Z.Z., Stroitel'stvo podvodnykh perekhodov magistral'nykh nefteprovodov metodom naklonno-napravlennogo bureniya (Construction of underwater crossings of main oil pipelines using directional drilling), Moscow: Nedra Publ., 2019, 357 p.
6. Kapaev R.A., Formation of the wellbore at the boundary of engineering-geological elements in the implementation of the HDD method in the construction of an underwater crossing (In Russ.), Ekspozitsiya Neft' Gaz, 2018, no. № 1 (61), pp. 56–60.
7. Kapaev R.A., Sharafutdinov Z.Z., Drilling tool structure and assembly impact on the construction process of underwater passages using directional drilling method (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2019, V. 9, no. 5, pp. 522–529.

The analysis of failures in underground pipelines indicates a significant difference in the causes and mechanisms of such failures depending on the pipeline deformation pattern after the soil movement. Thus, in the pipelines of Siberia, the main cause of failure is corrosion processes on the outer surface of the pipe after its insulation destruction, whereas for pipelines laid in permafrost soils accidents are due to the destruction arising from various structural and process defects under conditions of significant strains. We show that cyclic movements of the pipeline bottom deflection point in the area of flooded thermokarst with its uneven freezing in the autumn-winter period can cause the pipe wall torsion effect, combined with loading by internal pressure and a significant bending of the pipeline axis.

The paper considers fatigue failure mechanisms of a main pipeline wall under conditions of a complex stress-strain state (SSS) with a detected torsion element in the zone of ring assembly weld at the main pipeline exits from thermokarst into design position. Fractures in the pipe wall arise from the fusion area of the ring assembly weld and has all the signs of fatigue failure. The fractographic analysis of the fracture surface established the presence of three stages of fracture development: the initiation, stable growth, and surface fracture transition into a through fracture with areas of high local plastic deformation. In all development areas of the above fatigue failure of a pipe wall made of steel of the K56 strength grade, significant differences are recorded in the structure of the fatigue fracture surface, when compared with fractures obtained on these steels under the conditions of cleavage failure. All stages of failure include cleavage fragments together with quasi-brittle and brittle fracture areas. This indicates a significant contribution to the destruction of torsional strain in the form of micro-shear deformations, against the background of a biaxial SSS of the pipe wall loaded with internal pressure. On impact samples with a KCV notch, we conducted a comparative analysis of the influence exerted by plastic tensile and torsion strains on the fracture resistance parameters of K56 strength grade pipe steels under the conditions of a biaxial SSS.

References

1. Zorin E.E., Razrabotka osnov prognozirovaniya rabotosposobnosti svarnykh truboprovodov iz ferrito-perlitnykh staley s uchetom usloviy ekspluatatsii (Development of the basis for predicting the performance of welded pipelines made of ferritic-pearlitic steels, taking into account operating conditions): thesis of doctor of technical science, Moscow, 1993.

2. Rodionova S.G., Revel'-Muroz P.A., Lisin Yu.V. et al., Scientific-technical, socio-economic and legal aspects of oil and oil products transport reliability (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2016, no. 5 (25), pp. 20–31.

3. Neganov D.A., Makhutov N.A., Zorin N.E., Formation of requirements to reliability and security of the exploited sections of the linear part of trunk pipelines transportation of oil and oil products (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 6, pp. 106–112.

4. Geyt A.V., Zorin E.E., Mikhaylov I.I., Application of automated ultrasonic inspection systems in assessing the quality of girth welds of main pipelines (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2018, V. 8, no. 3, pp. 92–101.

5. Lanchakov G.A., Zorin E.E., Stepanenko A.I., Corrosion-mechanical strength and statistics of pipeline failures (In Russ.), Gazovaya promyshlennost', 1991, no. 10, pp. 14–19.

6. Zorin E.E., Efimov V.M., Tolstov A.E., Stress-strain state of subsurface pipeline in cryolithic zone (In Russ.), Neft', gaz i biznes, 2015, no. 9, pp. 9–12.

7. Larionov V.I., Gumerov A.K., Novikov P.A., Analysis of stress and strain state of a pipeline in karst areas (In Russ.), Vestnik MGTU im. N. E. Baumana. Ser. Mashinostroenie, 2012, no. 3(38), pp. 60–67.

8. Zorin A.E., Malyarevskaya E.K., Muradov A.V., Influence of pipe manufacturing technology on crack resistance of plastically deformed metal (In Russ.), Neft', gaz i biznes, 2010, no. 1, pp. 79–80.