In last years, the share of hard-to-recover oil reserves, concentrated in low-permeability carbonate reservoirs, where fractures mainly provide permeability, is increasing significantly. To date, fields of this type are located on the territory of the Russian Federation in Eastern Siberia, the Timan-Pechora region, the Caucasus, etc. The difficulties in developing such reservoirs are due to the irregular distribution of fractures and caverns, which are the main ways of fluid filtration and form the basis of the capacitive space of the fracture reservoir type. Rosneft Oil Company implements an extensive innovative program, using a technology for separating scattered and reflected waves on the base of the Gaussian beam method which is developing in Corporate Research and Design Complex

(RN-Krasnoyarsk­NIPIneft). The new technology has a high and uniform resolution, which makes it possible to obtain clear diffraction images of the fine structure of fractured-cavernous reservoirs. In this paper, we describe this technology. And present results of its verification on a synthetic model, describing a carbonate fractured-cavernous reservoir. Statistical characteristics of the model and corresponding images in scattered waves are compared, analyzed and discussed. The results prove, that some statistical characteristics are saved, in particular, the characteristic size of the heterogeneity of the near-fault zone. A systematic change in the parameters of the geological model was used to study how they display in seismic images by comparing their statistical characteristics. The application of the technology will increase the efficiency of the promotion of exploration and production drilling at the fields of Rosneft Oil Company with a difficult geological structure. First, it will be possible to reduce the geological risks associated with missed tectonic disturbances that limit the reservoir and directly affects the assessment of hydrocarbon reserves. Next, the technology allows localization of zones, associated with improved filtration and capacitance properties with high accuracy, which is of fundamental importance for geological modeling of complex reservoirs and subsequent successful drilling.

References

1. Kutovenko M.P., Protasov M.I., Cheverda V.A., Gaussian beams true-amplitude seismic imaging of multi-component data (In Russ.), Tekhnologii seysmorazvedki, 2010, no. 4, pp. 3 – 13.

2. Protasov M.I., Cheverda V.A., True amplitude seismic imaging of multicomponent walk-away VSP data (In Russ.), Tekhnologii seysmorazvedki, 2012, no. 3, pp. 31-41.

3. Protasov M.I., Cheverda V.A., Using Gaussian beams to build true-amplitude images (In Russ.), Tekhnologii seysmorazvedki, 2006, no. 4, pp. 3 – 10.

4. Kostin V.I., Lisitsa V.V., Reshetova G.V. et al., A finite-difference method for the numerical simulation of seismic wave propagation through multiscale media (In Russ.), Vychislitelʹnye metody i programmirovanie, 2011, V. 12, pp. 321 – 329.

5. Kostin V., Lisitsa V., Reshetova G. et al., Local time-space refinement for simulation of elastic wave propagation in multi-scale media, Journal of Computational Physics, 2015, V. 281, pp. 669 – 689.

6. Lisitsa V.V., Pozdnyakov V.A. et al., Scattered seismic responses: simulation and imaging. Part 1. Two-dimensional media (In Russ.), Tekhnologii seysmorazvedki, 2013, no. 1, pp. 46-58.

7. Tveranger J., Skar T., Braathen A., Incorporation of fault zones as volumes in reservoir models, Bolletino di Geofisica Teorica e Applicata, 2004, V. 45(1), pp. 316–318.

On the basis of long-term geological and geophysical studies and exploration wells drilling, the possibility to discover oil deposits in the Lower Cretaceous and Jurassic sediments of the Gulf of Ob in the Kara Sea is substantiated. On the territory of the Yamal-Nenets autonomous district, including the Ob and Taz Gulfs, several large deposits of hydrocarbons were discovered. The most studied is the middle part of the Gulf of Ob where gas-condensate fields in Cretaceous deposits are discovered. Perspective oil-gas complexes of the Jurassic and Neocomian age are characterized by the presence of continuous impermeable beds. These beds separate the allocated productive series. The production potential is confirmed by the results of on-shore deposits testing. To date, the reservoir properties of the Cretaceous sediments of the Ob and Taz Gulfs deposits have been studied in sufficient detail. However, there is no data on reservoir properties for sediments of the so-called “lower structural floor”, primarily for the Jurassic formations and, even more so, for the Paleozoic sediments. An important factor affecting the reservoirs properties is the presence of zones of abnormally high reservoir pressures observed in the entire thickness of the on-shore Jurassic sediments, starting with the Bazhenov formation. The results of testing of large on-shore deposits located on both sides of the Gulf of Ob (Parusovoye, Novoportovskoye etc.) showed that oil deposits is present in both the Neocomian and Jurassic sediments. It is confirmed by the opening and commercial operation of the Yarudeyskoye oil-gas-condensate field. Geochemical studies of the source strata, the degree of their catagenetic transformation, as well as a detailed analysis of the properties and composition of hydrocarbon fluids of the Lower-Middle Jurassic and pre-Jurassic sediments of the Northern part of the West Siberian petroleum basin showed the possibility of the presence of oil deposits in the Jurassic offshore sediments which are not yet studied by drilling. The current task is to identify new deep-seated anticlinal structures that can be commercial gas and oil reservoir.

References

1. Plesovskikh I.A., Nesterov I.I. (ml.), Nechiporuk L.A., Bochkarev V.S., Geologic structure of the northern West Siberian geosyneclise and new hydrocarbon-promising objects (In Russ.), Geologiya i geofizika = , 2009, V. 50, no. 9, pp. 1025–1034.

2. Brekhuntsov A.M., Nesterov I.I., Nechiporuk L.A. et al., Current hydrocarbon resources potential of Yamalo-Nenets autonomous okrug. Review of 2015 (In Russ.), Geologiya nefti i gaza = The journal Oil and Gas Geology, 2016, no. 5, pp. 45–49.

3. Brekhuntsova E.A., Kislukhin V.I., Features of formation and oil and gas potential of the sedimentary cover of the Yamal Peninsula (In Russ.), Geologiya, geofizika i razrabotka neftyanykh mestorozhdeniy, 2001, no. 5, pp. 36–41.

4. Nikitin B.A., Dzyublo A.D., Kholodilov V.A., Tsemkalo M.L., Oil and gas presence in Jurassic play and prospects for pre-Jurassic deposits in Ob-Tazov Bay and West Yamal offshore (In Russ.), Gazovaya promyshlennost', 2011, V. 661, Special Issue, pp. 16–24.

5. Raykevich A.I., Parasyna V.S., Kholodilov V.A. et al., Features of the geological structure and oil and gas potential of the Ob and Tazov Bays (In Russ.), Collected papers ”OOO “Gazflot” – 10 let na arkticheskom shel'fe” (“Gazflot” – 10 years on the Arctic shelf), Moscow, 2004, pp. 14–32.

6. Zonn M.S., Dzyublo A.D., Kollektory yurskogo neftegazonosnogo kompleksa severa Zapadnoy Sibiri (Collectors of the Jurassic oil and gas complex in the north of Western Siberia), Moscow: Nauka Publ., 1990, 88 p.

7. Nikitin B.A., Dzyublo A.D., Shuster V.L., Geologic and geophysical estimation of oil and gas content in deep-seated deposits of Jamal and Jamal shelf of Kara Sea (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 11, pp. 102–106.

8. Kiryukhina T.A., Ul'yanov G.V., Dzyublo A.D., Kholodilov V.A. et al., Geochemical aspects of Jurassic and pre-Jurassic plays oil and gas presence in northern East Siberia and its offshore (In Russ.), Gazovaya promyshlennost', 2011, no. 7, pp. 66–70.

9. Kiryukhina T.A., Zonn M.S., Dzyublo A.D., Geological and geochemical reasons of oil and gas content in the Lower Middle Jurassic and Pre-Jurassic sediments of the north of Western Siberia (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2004, no. 8, pp. 22–30.

The article is about the influence of lithofacies heterogeneity on the reservoir properties of the Upper Silurian carbonate sediment of R. Trebs and A. Titov fields and mapping methods for this heterogeneity. The work identified the factors that have had the greatest influence on the structure of the void space. The carbonate rocks are dolomites of Silurian Age, originally formed under the conditions of mobile shoal water of the ancient carbonate epicontinental platform that during epigenesis partly lost their primary properties. The void space of such reservoirs is modified due to the influence of post sedimentation processes (mineralization, desalination, dolomitization, and others). However, some connections between reservoir properties and facies conditions can be traced because post sedimentation processes acting selectively as facies zonality has not disrupted the structure of the void space, only emphasized its heterogeneity. The predominance of porosity types is intergranular, intercrystalline, small-cavernous that relate to the porous type reservoir gives opportunity for confident extrapolating the heterogeneity data obtained from laboratory studies for all pay zones.

According to core data, the change of reservoir properties is defined. The change was reconstructed according to logging data with well stock information. All this made it possible to map the variability of the void space for the reservoir pay zone. The obtained results are confirmed by the field performance as comparison of initial and relative well flow rates, as well as by their time gradient taking into account the selected thickness of the most permeable rocks.

The considered tools of geological and petrophysical mapping can be used with low reservoir thickness, high variability and seismic data do not allow make quantitative forecast in such complex reservoirs either.

References

1. Taninskaya N.V., Modeli karbonatnogo osadkonakopleniya v srednem ordovike-nizhnem devone Timano-Pechorskogo sedimentatsionnogo basseyna (Model of sedimentation of the Central Ordovician-Lower Devonian deposits of the Pechora-Barents Sea basin and reservoir forecast), St. Petersburg: Nedra Publ., 2004, pp. 108–120.

2. Zhemchugova V.A., Aktual'nye nauchno-tekhnicheskie problemy razvitiya geologo-geofizicheskikh, poiskovo-razvedochnykh i promyslovykh rabot v Respublike Komi (Current scientific and technical problems of the development of geological, geophysical, prospecting and fishing operations in the Komi Republic), Moscow: Gornaya kniga Publ., 2002, 244 p.

3. Lucia F.J., Carbonate reservoir characterization: an integrated approach, Springer, 2007, 336 p.

4. Dushin A.S., Rykus M.V., Naumov G.V., Gaymaletdinova G.F., Depositional environments, diagenetic processes and their impact on reservoir properties of Upper Silurian-Lower Devonian carbonates in R. Trebs and A. Titov fields (In Russ.), Neftegazovoe delo, 2015, no. 5, pp. 20–44, URL: http://ogbus.ru/issues/5_2015/ogbus_5_2015_p20–44_DushinAS_ru.pdf.

5. Dushin A., Gaymaletdinova G., Melnikov A., Predicting reservoir properties of carbonate rocks on the basis of their sedimentation heterogeneity and secondary transformations (In Russ.), SPE 187896-RU, 2017.

6. Taninskaya N.V., Modelʹ sedimentatsii sredneordoviksko-nizhnedevonskikh otlozheniy Pechoro-Barentsevomorskogo basseyna i prognoz kollektorov (Model of sedimentation of the Central Ordovician-Lower Devonian deposits of the Pechora-Barents Sea basin and reservoir forecast): thesis of doctor of geological and mineralogical science, St. Petersburg, 2001.

The article presents a comparative analysis of the world's largest oil and gas basins belonging to the MENA region (Middle East and North Africa). The eastern basins of the region, located in northeastern Africa, the Arabian Peninsula and the Middle East, are considered. The article shows that the oil and gas potential of the basins varies significantly, both in the resource and reserves as well by production values. The actual values of the annual and daily production of liquid and gas hydrocarbons, the volume of proven reserves in categories 1P and 2P of the largest oil and gas basins are presented. Together, the considered basins of the eastern part of the MENA region currently provide more than a quarter of the world's daily oil and gas production and include more than a third of the world's proven oil and gas reserves.

The specificity of the geological settings is characterized briefly, the dynamics of the increase in proved reserves while basins developing, and the dynamics of the field discoveries during exploration works are shown in comparison. The integral values of the success of exploratory drilling in the MENA region basins are calculated based on the ratio of successful and unsuccessful exploratory wells drilled over the entire period of exploration. The possible additional exploration potential of the oil and gas considered basins is characterized. Despite the long history of development, some of the basins still have significant geological exploration potential, which proves the relevance of geological exploration in them. In almost all the basins the main exploration prospects are associated with the search for non-structural traps (both on land and on the shelf), exploration of deep predominantly gas-bearing horizons, for the Zagros belt basins it is also possible to open structural traps in poorly studied areas.

References

1. Geologiya nefti (Petroleum geology), Part 2. Neftyanye mestorozhdeniya zarubezhnykh stran (Oil fields of foreign countries): edited by Vysotskiy I.V., Moscow: Nedra Publ., 1968, 804 p.

2. Aliev M.M., Vysotskiy V.I., Golenkova N.P., Timonin L.S., Geologicheskoe stroenie i neftegazonosnostʹ Severnoy Afriki, Blizhnego i Srednego Vostoka (Geological structure and petroleum potential of North Africa, the Near and Middle East), Baku: Ehlm Publ., 1979, 245 p.

3. Nairn A.E.M., Alsharhan A.S., Sedimentary basins and petroleum geology of the Middle East, Elsevier Science, 1997, 878 p.

4. Aqrawi A.A.M., Goff J.C., Horbury A.D., Sadooni F.N., The petroleum geology of Iraq, Scientific Press Ltd., 2010, 424 p.

The majority of natural hydrocarbon oilfields of the Far North are distinguished by frozen rocks and reservoirs with low pressures of hydraulic fracturing in their geological section. It makes complicate well construction. The height of frozen rocks can exceed 500 meters, and their natural temperature varies from 0 to -100 °C. The application of regular grouting mixtures in such geological conditions doesn’t provide a reliable cementing of the casing columns and formation isolation, as long as they harden for a long time, partially freeze, which adversely affects the working properties of cement stone. There is a risk of absorption of the grouting mixture, of the failure of the cement stone on exposure to cyclic freeze-thaw temperature. Therefore the main objective of grouting mixture formulation development for casing cementing in frozen rocks bedding interval – ensuring their freeze-proof properties, fast hardening without shrinkage strain. There is no serial production of the low density grouting mixtures for the low-temperature wells in the national industry. At the present time there are proposed various lightweight additives, among which zeolite is especially important. The paper reviews the problems of well cementing in the conditions of low reservoir pressure and temperature. The authors had developed and researched cement-zeolite grouting mixtures CZTS-1 (density of 1600-1610 kg/m3) and CZTS-2 (density of 1700-1720 kg/m3). The formulation contains binding material PCT I-50 (RF State Standard GOST 1581-96), synthetic zeolite of type NaA and NaX for CZTS-1 and CZTS-2 correspondingly (Technical Specification 2163-003-15285215-2006), stabilizing agent MK-85 under (Technical Specification TU 1714-457-05785388-2011), Natrosol 250EXR (TU 0799-001-99126491-2013), plasticizing agent SP-1 (TU 5870-005-58042865-2005). Process water was used as grouting fluid, 4 % solution of calcium chloride and 4% solution of mineralizing agent “Karnamin” were used for speeding up the setting time. We present the results of laboratory tests of basic working properties of cement-zeolite grouting mixture and stone at the temperatures ((20±2 and 5±2) °C. Optimal values of water-solid ratio for obtaining the grouting mixture of density 1600–1720 kg/m3 is 0.65-0.55.

References

1. Ovchinnikov P.V., Kuznetsov V.G., Frolov A.A., et al., Spetsial’nye tamponazhnye materialy dlya nizkotemperaturnykh skvazhin (Special cement slurry for low-temperature wells), Moscow: Nedra-Biznestsentr Publ., 2002, 115 p.

2. Oreshkin D.V., Frolov A.A., Ippolitov V.V., Problemy teploizolyatsionnykh tamponazhnykh materialov dlya usloviy mnogoletnikh merzlykh porod (Problems of thermal insulation cement slurry for permafrost conditions), Moscow: Nedra Publ., 2004, 232 p.

3. Beley I.I., Korostelev A.S., Karmatskikh S.A. et al., Cement mixtures for casing cementing in permafrost sections (In Russ.), Burenie i neft', 2014, no. 11, pp. 30–34.

4. Ovchinnikov V.P., Kuznetsov V.G., Frolov A.A., Gazgireev Yu.O., Lightweight grouting cement for low temperature wells (In Russ.), Burenie i neft', 2004, no. 5, pp. 32–33.

5. Ovchinnikov V.P., Kuznetsov V.G., Smyslov V.K. et al., Oblegchennyy tamponazhnyy rastvor dlya tsementirovaniya skvazhin v kriolitozone (Lightweight cement slurry for cementing wells in the permafrost zone), Proceedings of All-Russian Scientific and Technical Conference “Problemy sovershenstvovaniya tekhnologii stroitel'stva skvazhin i podgotovki kadrov dlya Zapadno-Sibirskogo neftedobyvayushchego kompleksa” (Problems of improving the technology of well construction and training for the West Siberian oil-producing complex), Tyumen': Publ. of TOSGU, 2000, pp. 56–57.

6. Oreshkin D.V., Belousov G.A., Efficiency of application of grouting materials with hollow glass microspheres (In Russ.), Vestnik Assotsiatsii burovykh podryadchikov, 2007, no 4, pp. 33–41.

7. Metodicheskie ukazaniya po ispytaniyu tamponazhnykh materialov dlya usloviy mnogoletnemerzlykh porod (Guidelines for testing cement materials for permafrost conditions), Moscow: Publ. of VNIIGAZ, 1982, 31 p.

8. Kubasov A.A., Zeolites - boiling stones (In Russ.), Sorosovskiy obrazovatel'nyy zhurnal, 1998, no. 7, pp. 70–76.

The theoretical and experimental studies of the reasons for the deviation of the filtration rate of liquids in porous media from the linear law in the displacement of oil by water are reviewed. Foreign and domestic experiments to study the filtration attenuation process associated with electrokinetic inhibition are analyzed. The results of experiments demonstrating that the slowing down of the flow during filtration of distilled water and aqueous solutions of potassium chloride in a porous medium occurs at low flow potentials are revealed. The obtained data do not fit into the framework of the considered concepts of the mechanisms of electrokinetic inhibition of filtration. The generalization of the results allowed the author to propose a compensation mechanism for electrokinetic inhibition, explaining the decrease in the filtration rate of distilled water through a porous medium at low values of flow potentials, not fully compensating for the magnetic moments of chemical compounds that are crystallized or adsorbed on the surface of the pore channel as a result of natural watering, the magnetic moments of dissociated salt molecules water. In this paper, based on the application of the compensatory mechanism of the electrokinetic filtration inhibition process, the concepts of the features of the natural watering of the reservoir, the study of the microcomponent composition of rocks, the identification and identification of microcomponents characterizing natural watering, the nature of the changes and differences in the water permeability of carbonate and terrigenous reservoir rocks during filtration low-mineralized water, as well as increasing the mineralization of the pumped water, is explained. The possibility of using the developed approach to explain the reasons for the increase in the water saturation of rocks wetted by water, to reduce the water cut in the well and the mechanism for extracting residual oil, as well as to justify the technological parameters of the process of influencing the highly watered layer with low mineralized water is shown. The efficiency of low-mineralized water injection technology at the later stages of oil field operation is considered to be proved by field experiments, however, the mechanism adequately reflecting the process of oil recovery increase during injection of low-mineralized water into the high-water reservoir has not been proposed so far.

References

1. Dukhin S.S., Elektroprovodnost' i elektrokineticheskie svoystva dispersnykh sistem (Electrical conductivity and electrokinetic properties of dispersed systems), Kiev: Naukova dumka Publ., 1975, 246 p.

2. Grigorov O.N., Elektrokineticheskie yavleniya (Electrokinetic phenomena), Leningrad: Publ. of LSU, 1973, 199 p.

3. Simkin E.M., The role of electrokinetic phenomena in filtration processes (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1979, no. 3, pp. 53–56.

4. Dresner L., Electrokinetic phenomena in charged microcapillaries, L. Phis. Chem., 1963, V. 67, pp. 1635–1641.

5. Romm E.S., Features of electrokinetic phenomena in thin capillaries (In Russ.), Kolloidnyy zhurnal, 1979, V. 41, no. 5, pp. 895–901.

6. Burgreen D., Nakache F.R., Efficiency of pumping and power generation in ultrafine electrokinetic systems, L. of Applied Mechanics, 1965, Sept., pp. 675–677.

7. Sigal V.L., Issledovanie stroeniya diffuznogo dvoynogo sloya v dispersnykh sistemakh (Investigation of the structure of a diffuse double layer in dispersed systems): thesis of candidate of physical and mathematical science, Moscow, 1973.

8. Churaev N.V., Deryagin B.V., Effect of overlap of diffuse ionic layers on electrokinetic phenomena in thin films and pores (In Russ.), Kolloidnyy zhurnal, 1966, V. 28, no. 5, pp. 751–757.

9. Zhukov I.I., Kryukov N.A., Poverkhnostnaya provodimost' i elektrokineticheskie svoystva tverdykh dispersoidov (kvarts, korund) (Surface conductivity and electrokinetic properties of solid dispersoids (quartz, corundum)), Moscow: Publ. of USSR AS, 1952, pp. 318–346.

10. Henniker J.C., The depth of the surface zone of a liquid, Revs Modern Phys., 1949, V. 21, pp. 322–341.

11. Karnyushina E.E., Levchenko V.A., Serpikova V.M., Influence of stadial and superimposed processes on the change of carbonate rocks of the Kozhasai oil field (Caspian Sea) (In Russ.), Vestnik MGU. Seriya 4. Geologiya, 1999, no. 3, pp. 29–35.

12. Akhmetov N.Z., Bakhtin A.I., Vasil'eva T.L. et al., Possibilities for preliminary assessment of carbonate reservoir productivity based on lithologic and mineralogical data (In Russ.), Georesursy, 2001, no. 2, pp. 8–15.

13. Seccombe J., Lager A., Jerauld G., Jhaveri B., Buikema T., Bassler S., Denis J., Webb K., Cockin A., Fueg E., Paskvan F., Demonstration of low-salinity EOR at interwell scale, Endicott Field, Alaska, SPE 129692-MS , 2010.

Ultra-low permeability estimation is still one of the highly relevant subject of modern petrophysics and shale-oil industry. Popular unsteady-state gas filtration laboratory methodic are not able to provide precise and unique permeability value because of algorithms complexity. Again the need to estimate sample porosity before permeability evaluation makes test protocol time consuming, too. From other hand steady-state gas filtration is classical for conventional reservoir but becomes unpractical when one use it to evaluate ultra-low gas permeability because of huge test duration and enormous result’s sensibility to temperature stability. New method and apparatus for fast and precise ultra-low steady-state gas permeability estimation based on a simple analytical solution is presented in the paper. New approach to the gas discharge evaluation allows to estimate core plugs permeability in the range from 10-5 μm2 to 10-18 μm2 with high confidence. It is important that plugs may be affected by confining pressure up to 70 MPa. Good correlation was achieved by comparison the results of gas permeability determination by new method and by modified pressure pulse decay method in plug’s permeability range from 10-5 μm2 до 10-9 μm2. New approach allows to apply confining pressure up to 70 MPa to the plug preventing gas filtration along the artificial micro fractures. Practical application of the new method to the Bazhen Fm shale and it’s lithological analogues is demonstrated in the paper.

References

1. Brace W.F., Walsh J.B., Frangos W.T., Permeability of granite under high pressure, Journal of Geophysical Research, 1968, V. 73, pp. 2225–2236.

2. Jones S.C., A technique for faster pulse decay permeability measurements in tight rocks, SPE 28450-PA, 1997.

3. Luffel D.L., Hopkins C.W., Matrix permeability measurement of gas productive shales, SPE 26633-MS, 1993.

4. Jones S.C., A rapid accurate unsteady-state permeameter Klinkenberg permeameter, SPE 3535-PA, 1972.

5. Boulin P.F., Bretonnier P., Gland N., Lombard J.M., Contribution of the steady state method to water permeability measurement in very low permeability porous media, Oil Gas Sci. Technol., 2012, V. 67(3), pp. 387–401.

6. Skripkin A.G., Parnachev S.V., Baranov V.E., Zakharov S.V., Experience of using different methods for evaluation of reservoir properties of nanopermeable rocks (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 11, pp. 59–61.

An important task of field development on the stage of production decline is to enhance oil recovery using well stimulation and waterflooding optimization. Key feature of the article is based on handling with carbonate reservoir. Those types of oil fields involve more detailed studying and detailed acquisition, accurate evaluation of geological-geophysical and field production data. This approach is intended to organize the process of studying carbonates and increase exploration maturity and particularization before development decision is made. Reserves decline of oil fields with fractured carbonate reservoir is crucially complicated due to formation vertical heterogeneity, occurrence of separate filtration pathways and as a consequence poor sweep efficiency of reservoir development both in vertical and lateral direction. As a result – there is a failure to achieve expected level of recovery factor.

There is no clear understanding of mechanism of reserves recovery, quite how the process of oil displacement happens: either in vertical direction or in a layered way. More uncertainties in the research process are brought by active aquifer, reservoir pressure maintenance system directly below the OWC and nonuniform recovery at vertical scale.

In this article various approaches are reviewed to analyze, organize and primary evaluation of field development status using example of locally isolated area of one of the major fields at Central Khoreiver Uplift, consisted of carbonate reservoir. The item is divided into several stages, which form the base of decision-making of field development. A simulation model is chosen as a base tool for project development, which stores findings of primary analysis. Resultant model allows evaluating inter-well effects and choosing maximum preferable variant.

References

1. Wolcott D., Applied waterflood field development, Publ. of Schlumberger, 2001, 142 p.

2. Heffer Kes J. et al., Low-cost monitoring of inter-well reservoir communication paths through correlations in well rate fluctuations: Case studies from mature fields in the North Sea, SPE 130734-MS, 2010.

3. Dake L.P., The practice of reservoir engineering, Elsevier Science, 2001, 570 p.

4. Yudin E.V., Bagmanov R.D., Khayrullin M.M. et al., Development of approach to modelling complex structure carbonate reservoirs using example of the Central Khoreyver Uplift fields (In Russ.), SPE 187811-RU, 2017.

The calculation of bottomhole pressure is the most important task of monitoring the operation of oil producing wells. When it is impossible to directly measure it, in practice, calculation methods are used, including methods for recalculating wellhead parameters (annular pressure, dynamic level, etc.). For this purpose, LUKOIL-PERM uses two methods for recalculating wellhead parameters into bottomhole pressure: one is fully analytical, and another is analytical with address correlations. The article presents the results of assessing the reliability of determining bottomhole pressure using these methods. The material was used for two fields of the Perm Territory - Magovskoye and Shershnevskoye, including the results of parallel wellhead and deep measurements. Comparison of actual and calculated by existing methods values of downhole pressure showed a low reliability of their application. The main reason for the low reliability of the applied methods should be considered the need to use the characteristics of the gas-liquid mixture in the wellbore and the annulus space, which cannot be determined accurately enough due to the complex nature of multiphase flow. The article proposes a fundamentally different approach, consisting in the construction of multivariate mathematical models based on statistical processing of the accumulated material of parallel wellhead and depth measurements. For this purpose, data from 235 wells surveys from the fields under consideration are involved. As the initial data in the developed method, it is proposed to use well performance indicators, the definition of which is not accompanied by difficulties: oil and liquid flow rate, water content, dynamic level, annular pressure, pump depth and its immersion under dynamic level, distance to water-oil contact. Multidimensional mathematical models are built for both fields under consideration. To assess the reliability of the developed methodology based on the use of multivariate models, the tools of mathematical statistics were used. The developed technique has demonstrated its high accuracy compared to the currently used methods for determining bottomhole pressure when recalculated from wellhead parameters.

References

1. Chernykh I.A., Razrabotka metodiki monitoringa zaboynogo davleniya po dannym promyslovo-geofizicheskikh issledovaniy skvazhin (Development of a bottomhole pressure monitoring method based on field geophysical well data): thesis of candidate of technical science, Permʹ, 2018.

2. Chernykh I.A., Determination of bottomhole pressure by using multivariate statistical models (on example of formation TL-BB Yurchukskoie field) (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo, 2016, V. 15, no. 21, pp. 320–328, DOI: 10.15593/2224-9923/2016.21.3.

3. Galkin V.I., Ponomareva I.N., Cherepanov S.S., Development of the methodology for evaluation of possibilities to determine reservoir types based on pressure build-up curves, geological and reservoir properties of the formation (case study of famen deposits of Ozernoe field) (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2015, no. 17, pp. 32–40, DOI: 10.15593/2224-9923/2015.17.4.

4. Bikbulatov S.M., Pashali A.A., Analysis and selection of methods for calculating the pressure gradient in the wellbore (In Russ.), Ehlektronnyy nauchnyy zhurnal “Neftegazovoe delo”, 2005, no. 2, URL: http://ogbus.ru/files/ogbus/authors/Bikbulatov/Bikbulatov_1.pdf.

5. Venttselʹ E.S., Issledovanie operatsiy (Operations research), Moscow: Sovetskoe radio Publ., 1972, 407 p.

6. Galkin V.I., Ponomareva I.N., Koltyrin A.N., Development of probabilistic and statistical models for evaluation of the effectiveness of proppant hydraulic fracturing (on example of the Tl-Bb reservoir of the Batyrbayskoe field) (In Russ.), Vestnik Permskogo natsionalʹnogo issledovatelʹskogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2018, V. 17, no. 1, pp. 37–49, DOI: 10.15593/2224-9923/2018.1.4

7. Gladkikh E.A., Khizhnyak G.P., Galkin V.I., Popov N.A., Method for evaluation of oil displacement coefficient based on conventional core analysis (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2017, V. 16, no. 3, pp. 225–237, DOI: 10.15593/2224-9923/2017.3.3.

The actuality of increasing the oil (ORF), gas (GRF), condensate (CRF) recovery factors of liquid and gaseous hydrocarbon field, developed through artificial methods of reservoir pressure maintenance, involving the injection of water or other displacing agents, does not depart from the scientific and technical agenda for the oil and gas industry.

The solution of direct problems of filtration of multiphase fluids through an inhomogeneous porous medium by analytical or numerical methods is faced with the problem of taking into account the instability of the displacement front and, as a result, due to a jump in determining water saturation and parameters that depends on water saturation. The proposed solution to the inverse problem allows implicitly taking into account the instability of the displacement front and predicts the consequences of a natural intermittent change in water saturation and dependent parameters using a discriminant analysis of the growth model. On the basis of the proposed solutions, criteria are formulated that enable timely detection of the consequences of loss of the displacement front stability and targeted adjustment of the waterflood system by forcing or limiting the operating modes of production and injection wells in accordance with established discriminant analysis criteria. The mobilization of the injected water and the regulation of the selection of liquid, more precisely, water and oil, based on the discriminant criterion, allow solving an important practical problem in circumventing difficult to solve direct deterministic problems and methods for solving them. This opens up the possibility of systemic optimization of non-stationary waterflooding and the prospect of enhanced oil recovery from field and the intensification of hydrocarbon production.

References

1. Wuskoff R.D., Votset H.F., The flow of gas liquid mixtures through unconsolidated sands, Physics, 1936, V. 7, pp. 3–25.

2. Leverett M.C., Lewis W.B., Steady flow of gas-oil-water mixtures through unconsolidated sands, SPE 941107-G, 1941.

3. Buckley I., Leverett M.S., Mechanism of fluid displacement in sands, SPE 942107-G, 1942.

4. Muskat M., Calculation of initial fluid distribution in oil reservoirs, SPE 949119-G, 1949.

5. Charnyy I.A., Podzemnaya gidrogazodinamika (Underground fluid dynamics), Moscow: Gostoptekhizdat Publ., 1963, 397 p.

6. Kreyg F.F., Razrabotka neftyanykh mestorozhdeniy pri zavodnenii (Applied waterflood field development), Moscow: Nedra Publ., 1974, 191 p.

7. Aziz Kh., Settari A., Petroleum reservoir simulation, Applied Science Publishers, 1979, 476 p.

8. Shakhverdiev A.Kh., Sistemnaya optimizatsiya protsessa razrabotki neftyanykh mestorozhdeniy (System optimization of oil field development process), Moscow: Nedra Publ., 2004, 452 p.

9. Mirzadzhanzade A.Kh., Shakhverdiev A.Kh., Dinamicheskie protsessy v neftegazodobyche: sistemnyy analiz, diagnoz, prognoz (Dynamic processes in the oil and gas production: systems analysis, diagnosis, prognosis), Moscow: Nauka Publ., 1997, 254 p.

10. Mandrik I.E., Panakhov G.M., Shakhverdiev A.Kh., Nauchno-metodicheskie i tekhnologicheskie osnovy optimizatsii protsessa povysheniya nefteotdachi plastov (Scientific and methodological and technological basis for EOR optimization), Moscow: Neftyanoe khozyaystvo Publ., 2010, 288 p.

11. Patent no. 2382877 RF, Oil field development method, Inventors: Shakhverdiev A.Kh., Mandrik I.E., Panakhov G.M., Abbasov E.M., Aliev G.M.

12. Shakhverdiev A.Kh., Once again about oil recovery factor (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 1, pp. 44–48.

13. Arnol'd V.I., Teoriya katastrof (Catastrophe theory), Moscow: Nauka Publ., 1990, 128 p.

14. Thompson J.M.T., Instabilities and catastrophes in science and engineering, Wiley, Chichester, 1982.

15. Nicolis G., Prigogine I., Self-organization in nonequilibrium systems: From dissipative structures to order through fluctuations, Publisher: John Wiley & Sons, 1977, 512 p.

The thermal steam effect (TSE) on oil-saturated carbonate rock with residual water saturation (case study of core material taken from Chernoozerskoe and Pionerskoe oil fields of the Republic of Tatarstan) was simulated using a specially designed laboratory test bench. In advance, in order to study the effect of the mineral composition of the rock on the results of thermal stimulation, thermal oxidation of the Chernoozerskoye and Pionerskoye oils in carbonate rock and quartz sandstone was investigated, and it was shown that the carbonate rock shifted the low-temperature oxidation onset temperature towards higher temperatures, and the process of low-temperature oxidation occurred faster. It was shown that during TSE in the oil-saturated rock the low-temperature oxidation of oil occurred, and a change in the gas relative permeability of rock was detected. It was established that steam with a temperature of 150 °C did not pass through the pore space of a low-permeable carbonate core sample. In increasing steam temperature up to 200–300 °C the vapor began to pass through a core. For a highly permeable carbonate core sample it was determined that an increase of TSE temperature from 200 to 350 °C leaded to an increase in gas relative permeability by 6.8 times.

The oil-displacement efficiency by steam in our experiments performed at a temperature of 250–300 °C was less than 30 %. In light of this, the thermal steam stimulation for the development of heterogeneous carbonate oil reservoirs was not recommended. For development of carbonate reservoir the combination of the TSE method with solvent injection was recommended. It was shown that combination of the TSE with solvent injection could increase the oil-displacement efficiency up to 70 %.

References

1. Muslimov R.Kh., Sovremennye metody povysheniya nefteizvlecheniya: proektirovanie, optimizatsiya i otsenka effektivnosti (Modern methods of enhanced oil recovery: the design, optimization and assessment of efficiency), Kazan': Fen Publ., 2005, 688 p.

2. Melekhin S.V., Mikhaylov N.N., Experimental study of the residual oilmobilization at carbonate reservoirs flooding (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 8, pp. 72–76.

3. Antoniadi D.G., Garushev A.R., Shikhanov V.G., Nastolʹnaya kniga po termicheskim metodam dobychi nefti (Handbook on thermal methods of oil production), Krasnodar: Sovetskaya Kubanʹ Publ., 2000, 464 p.

4. Shihab Mazin Najeeb, Substantiation of thermal effects on carbonate formations with high-viscosity oil of Northern Iraq Qaiyarah oilfield (In Russ.), Neftegazovoe delo, 2011, no. 3, pp. 450–461.

5. Yusupova T.N., Petrova L.M., Mukhametshin R.Z. et al., Distribution and composition of organic matter in oil – and bitumen-containing rocks in deposits of different ages, J. Thermal Analysis and Calorimetry, 1999, V. 55, pp. 99–107.

6. Petrov Al.A., Uglevodorody nefti (Petroleum hydrocarbons), Moscow: Nauka Publ., 1984, 264 p.

The article presents the results of the studies of corrosion activity of water produced from the White Tiger, White Rabbit and Dragon oilfields operated by Vietsovpetro JV. Produced water in Vietsovpetro is a mixture of formation water and treated seawater used for waterflooding. There are substantial differences in chemical composition and content of corrosive components in water between different oilfields and even within one oilfield. Maturing of the oilfields leads to an increase in water cuts and in aggressive components content in produced water.

Oil gathering pipelines and oil processing equipment are made of ASTM A106, API 5X carbon steels. In Vietsovpetro the pipes and equipment made of carbon steels have been used successfully for more than 25 years, but in recent years corrosion damage was noticed on the inner surfaces of the pipes the oil gathering and transportation system. It was found that the present rate of corrosion of carbon steel in the conditions at which the system of gathering and transportation of the gas-liquid products operates (45 °С, 0.1 MPa) is 0.22-0.31 mm per year. At elevated pressures and temperatures (120 °С, 10 MPa) the corrosion rates increase to 0.26-0.64 mm per year. Corrosion aggressiveness of produced water is caused primarily by carbon dioxide, water and solid particles. The results of inspection of pipelines wall thickness after corrosive impact prove the high aggressive activity of produced water. Electrochemical corrosion that causes local defects (blisters) on the inner surface of the oil pipelines, transporting produced fluids with high water content, is caused primarily by formation of a separate water phase in the pipes and by presence of aggressive components in water.

A field trial of corrosion inhibitor injection into the gathering and transportation system was performed to reduce the internal corrosion. It was found that in presence of corrosion inhibitor the rate of corrosion lowers from 0.31 to 0.052 mm per year.

References

1. Zav’yalov V.V., Problemy ekspluatatsionnoy nadezhnosti truboprovodov na pozdney stadia razrabotki mestorozhdeniy (Pipelines operating reliability problems in the late stages of field development), Moscow: Publ. of VNIIOENG, 2005, 332 p.

2. Gordeev P.V., Shemelin V.A., Shulyakova O.K., Gidrogeologiya (Hydrogeology), Moscow: Vysshaya shkola Publ., 1990, 471 p.

3. Bushkovskiy A.L., Ivanov A.N., Chan Van Vinh, Le Cong Thuy, Corrosion activity of wells production and efficiency of protection of Vietsovpetro JV oil & gas producing equipment (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 7, pp. 112–115.

In this article we consider information on the use of a new hydraulic fracturing fluid based on a polysaccharide that is not related to traditionally used guar. Guar-based polymers have reliably recommended themselves as the basis of fluids for hydraulic fracturing, showing their best sand-carrying capacities in a wide range of gel former concentrations, that allow to pump large volumes of high concentration proppant. However, it is often necessary to conduct hydraulic fracturing in complex geological conditions caused by weak interlayer barrier separating the oil-saturated formation from the water-saturated one, and breakthrough of that barrier increases the risk of well stream watering.

To reduce these risks, various methods are used such as reducing the viscosity of hydraulic fracturing fluid, volume of fluid and flow rate. A decrease in the viscosity of traditional guar-based fluids (up to the viscosity of a linear gel) is inevitably accompanied significant sedimentation of proppant and leads to its uneven distribution in the fracture height, that means the potential reduction in fracture conductivity and also significantly increases the risk of premature stopping of the hydraulic fracturing.

Innovative fracturing fluid SI Bioxan has the properties to keep the proppant in suspension at low viscosity (viscosity can be only a few tens of centipoise) and, thus, solve the problem of hydraulic fracturing on such complicated objects: evenly distribute the proppant vertically in the fracture, conduct hydraulic fracturing with minimal risks for a breakthrough in water-saturated reservoirs, reducing potential threats of premature stopping of hydraulic fracturing.

This technology was tested on the fields of the republics of Udmurtia and Tatarstan and showed high efficiency, creating reasonable prerequisites for use in other fields of the Russian Federation with similar complicated geological conditions.

References

1. Gavura V.E., Geologiya i razrabotka neftyanykh i gazoneftyanykh mestorozhdeniy (Geology and development of oil and oil-and-gas fields), Moscow: Publ. of VNIIOENG, 1995, 496 p.

2. Salimov V.G., Ibragimov N.G., Nasybullin A.V., Salimov O.G., Gidravlicheskiy razryv karbonatnykh kollektorov (Hydraulic fracturing of carbonate reservoirs), Moscow: Neftyanoe khozyaystvo Publ., 2013, 472 p.

Under conditions of natural depletion of producing fields achieving optimal energy efficiency of oil production processes become increasingly important. About one third of total power consumption is attributed to reservoir pressure maintenance. At the same time, more than half of nonproductive time is associated with low efficiency of dynamic-action pumping units. Positive displacement plunger-type pumps can be used as suitable alternatives in reservoir pressure maintenance systems. However, implementation of positive displacement pumps presents some challenges, related primarily to operational aspects peculiar to such pumps, when mechanical effects, associated directly with operation of pump components, are observed together with pressure fluctuations affecting the overall operability of pumping equipment. Long-term experience in controllable operation of positive displacement pumping units enabled identification of common intrinsic problems regardless of pump manufacturer. The paper addresses practical aspects of positive displacement plunger-type pump applications for reservoir pressure maintenance purposes in the course of oil fields development. Comparative analysis of specific power consumption for dynamic-action and positive displacement pumps is provided depending on the developed pressure. Practices for reduction of pump vibrations are presented as well as the results of in-situ measurements, various pressure compensators are compared in terms of performance efficiency. The paper also considers the causes of cavitation, its effects on positive displacement pumps and prevention methods. Steel grades used by Russian and foreign pump manufacturers are discussed as well as plunger packing materials that have exhibited the best failure-free operation time characteristics in the main components of positive displacement pumps.

References

1. Fattakhov R.B., Konnov V.A., Ibragimov N.G. et al., Application of positive-displacement pumps for energy savings in reservoir-pressure maintenance systems (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 7, pp. 54–57.

2. Sushkov V.V., Veliev M.K., Gladkikh T.D., Optimizatsiya upravleniya rezhimami raboty i minimizatsiya poter' elektroenergii v elektrotekhnicheskikh kompleksakh neftegazodobyvayushchikh predpriyatiy (Optimization of operating modes management and minimization of energy losses in electrical systems of oil and gas producing enterprises), Tyumen': Publ. of TSPTU, 2014, 163 p.

3. Konnov V.A., Fattakhov R.B., Analysis of results of experimental operation of positive displacement pumps used for water injection into a formation (In Russ.), Oborudovanie i tekhnologii dlya neftegazovogo kompleksa, 2014, no. 5, pp. 12–15.

4. Pavlov G.A., Gorbatikov V.A., On the problems of energy saving and energy efficiency in reservoir pressure maintenance systems (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2011, no. 7, pp. 118–119.

5. Gilyazov V.M., Ksenofontov D.V., Experience and perspectives of using domestic-produced volumetric pumps in the reservoir pressure maintenance system in Elkhovneft (In Russ.), Inzhenernaya praktika = Oilfield Engineering, 2016, no. 7, pp. 24–27.

6. Slugin D.N., Adoption of energy efficient positive displacement pump to maintain reservoir pressure (In Russ.), Inzhenernaya praktika = Oilfield Engineering, 2013, no. 6–7, pp. 152–155.

The number of wells repairs at gas and oil fields in the Krasnodar region is growing from year to year. Each well repair is directly related to the work on cleaning the bottom-hole and wellbore. Before the descent of any downhole equipment, as well as after the hydraulic fracturing, a careful well preparation is required. Reducing the time and financial costs of well operations is one of the urgent tasks for service organizations and subsoil users.

A number of hydrodynamic and cavitation devices have been developed and tested in well conditions at the gas and oil fields of the Krasnodar region, as well as a technology for the normalization of the bottom-hole. These devices and technology differ from the well-known ones by the destruction of cemented sand plugs and "sintered" proppant due to the hydromonitor, erosion effect, as amplitude and frequency oscillations arising at the expiration of high-pressure cavitation jets of the washing liquid. The presence of versions of the injected nozzles with different diameters of the critical section allows to operate the developed device in a wide range of depths of wells and used washing units. The control and regulation of process of destruction of the tubes is carried out during lowering of the lifting operation. The technology is feasible on the regular equipment of well repair teams. Full-scale well studies have confirmed the high efficiency, performance and reliability of this device.

References

1. Dmitruk V.V., Rakhimov S.N., Kustyshev D.A., Nikiforov V.N., Post-fracture bottom hole cleaning from proppant plugs using coiled tubing (In Russ.), Vremya koltyubinga. Vremya GRP = Scientific and practical Coiled Tubing Times Journal, 2014, no. 2, pp. 68–71.

2. Nifontov Yu.A., Kleshchenko I.I., Remont neftyanykh i gazovykh skvazhin (Repair of oil and gas wells), Part 1, St. Petersburg: Professional Publ., 2005, 351 p.

3. Omel'yanyuk M.V., Pakhlyan I.A., Gidrodinamicheskie i kavitatsionnye struynye tekhnologii v neftegazovom dele (Hydrodynamic and cavitation jet technology in oil and gas business), Krasnodar: Publ. of CSTU, 2017, 215 p.

4. Kholpanov L.P., Zaporozhets E.P., Zibert G.K., Kashchitskiy Yu.A., Matematicheskoe modelirovanie nelineynykh termogidrogazodinamicheskikh protsessov v mnogokomponentnykh struynykh techeniyakh (Mathematical modeling of nonlinear thermohydrogasdynamic processes in multicomponent jet flows), Moscow: Nauka Publ., 1998, 320 p.

5. Ibragimov L.Kh., Mishchenko I.T., Cheloyants D.K., Intensifikatsiya dobychi nefti (Oil well stimulation), Moscow: Nauka Publ., 2000, 414 p.

6. Pilipenko V.V., K opredeleniyu chastot kolebaniy davleniya, sozdavaemykh kavitatsionnym generatorom (To the determination of the frequency of pressure fluctuations generated by a cavitation generator), Collected papers “Dinamika nasosnykh sistem” (Dynamics of pumping systems), Kiev: Naukova dumka Publ., 1980, pp. 127–131.

The issue of synthesis of models of the well – oil well pump system is considered taking into account the characteristics of the mechanical part of the pumping unit and the drive. This model allows to obtain dynacards and wattmeterograms, which is important when using it to develop diagnostic and control algorithms. An example of using the mechanics of a traditional sucker rod pumping unit is given. The necessary formulas for modeling the oil production process are presented. The obtained model can serve as a basis for virtual and physical stands for testing the algorithms for controlling and diagnosing sucker rod pumping unit and testing the efficiency of their control systems. Conclusions are made about the applicability of this approach to the synthesis of models and for other types of actuators of sucker rod pumping unit. All necessary formulas for modelling process of oil extraction are given. Results of modelling of system taking into account characteristics of a mechanical part of pumping unit and drive characteristics are presented. Moment components on an electric motor shaft are considered. It is shown that absence of even one component of this moment leads to essential errors of transformation of the data wattmeterograms in the data dynacards. The conclusion is made that for exact transformation of the data wattmeterograms in the dynacards it is necessary to consider enough great number of parameters of a mechanical part of the machine tool-rocking chair that existing methods of the given transformation yet do not provide is drawn. Recommendations on the use of dynacards and wattmetrograms are made.

References

1. URL: http://www.danfoss.com/NR/rdonlyres/90BCF710-9C97-4F9C-9EF5-F9274DA9A842/0/salt_broshyura.pdf.

2. Krichke V.O., Krichke V.V., Groman A.O., A new era in the management of pumping complexes (In Russ.), Sovremennye naukoemkie tekhnologii, 2009, no. 1, pp. 20–23.

3. Tagirova K.F., Vul'fin A.M., Ramazanov A.R., Fatkulov A.A., Improving the efficiency of operation of sucker-rod pumping unit (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 7, pp. 82–85.

4. Guluev G.A., Pashaev A.B., Pashaev F.G. et al., The Algorithm of determination of rod force from power consumption of the electric drive in the operating pumping unit (In Russ.), Mekhatronika, avtomatizatsiya, upravlenie, 2012, no. 11, pp. 55–58.

5. Zubairov I.F., Smart well - improving the efficiency of artificial lift (In Russ.), Inzhenernaya praktika, 2011, no. 5, pp. 84–89.

6. Gibbs S.G., Neely A.B., Computer diagnosis of down-hole conditions in sucker rod pumping wells, Journal of Petroleum Technology, 1966, V. 18, no. 1, pp. 91–98.

7. Gibbs S.G., Predicting the behavior of sucker-rod pumping systems, SPE-588-PA, 1963.

8. Kas'yanov V.M., Analiticheskiy metod kontrolya raboty glubinnykh shtangovykh nasosov (Analytical method of controlling the operation of submersible sucker rod pumps), Moscow: Publ. of VNIIOENG, 1973, 95 p.

9. Urazakov K.R., Bakhtizin R.N., Ismagilov S.F., Topol'nikov A.S., Theoretical dynamometer card calculation taking into account complications in the sucker rod pump operation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 1, pp. 90–93.

10. Urazakov K.R., Latypov B.M., Komkov A.G., Research of efficiency of differential Rod pumps for extraction of high-viscosity oil (In Russ.), Territoriya NEFTEGAZ, 2018, no. 5, pp. 34–40.

11. Kovshov V.D., Sidorov M.E., Svetlakova S.V., Simulation of beam pumping unit dynamometer. Normal pump operation (In Russ.), Neftegazovoe delo, 2004, no. 2, pp. 75–81.

12. Kovshov V.D., Sidorov M.E., Svetlakova S.V., Dynamometer test, modeling and diagnostics of the state of sucker rod pumping unit (In Russ.), Izvestiya vuzov. Neft' i gaz, 2011, no. 3, pp. 25–29.

13. Sadov V.B., Simulation of dynamometer cards with various defects of oil well equipment (In Russ.), Vestnik Yuzhno-Ural'skogo gosudarstvennogo universiteta. Seriya: Komp'yuternye tekhnologii, upravlenie, radioelektronika, 2013, V. 13, no. 1, pp. 16–25.

14. Firago B.I., Pavlyachik L.B., Reguliruemye elektroprivody peremennogo toka (Adjustable AC drives), Minsk: Tekhnoperspektiva Publ., 2006, 363 p.

15. Veshenevskiy S.N., Kharakteristiki dvigateley v elektroprivode (Characteristics of engines in the drive), Moscow: Energiya Publ., 1977, 432 p.

This article presents the results of studies of the main metal parts of pipeline valves and pumping equipment of domestic and foreign production, which have been used for over 30 years at the oil and oil products pipeline transport facilities of the Transneft system entities. The studies included determination of strength and viscoplastic properties, as well as metallographic studies of the base metal structure of case-shaped parts and stems of pipeline valves (slide valves, wedge valves, gate valves, check valves) and pumping equipment. According to the research results, the mechanical properties of the base metal of the parts after long-term operation were compared with the mechanical properties of the parts currently produced by domestic manufacturers.

An integral part of oil and oil products pipeline systems is pipeline valves and pumping equipment. Continuous improvement of the manufacturing process of shut-off valves, ensuring the mechanical characteristics of parts at a high level, is one of the key factors ensuring the reliability of the entire pipeline system as a whole. The purpose of this work was to determine the actual mechanical properties and microstructure of pumping equipment and valve parts after long-term operation and compare them with the technical requirements currently in force. The results of the analysis showed that the characteristics of materials of shut-off valves and pumping equipment parts currently produced, in general, exceed the characteristics of materials used in the manufacture of equipment that served as research subjects.

Based on the analysis of the research data results, it was concluded that the equipment currently manufactured has the best reliability targets.

References

1. Shlyamnev A.P. et al., Korrozionnostoykie, zharostoykie i vysokoprochnye stali i splavy: spravochnik (Corrosion-resistant, heat-resistant and high-strength steels and alloys), Moscow: Prommet-splav Publ., 2008, 332 p.

2. Kazantsev M.N., Flegentov I.A., Zhevelev O.Yu., Kvasnyak V.B., Zhukov M.V., Measures for improving the protective qualities of wear-resistant metal coatings in shut-off valves slide GATES (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2016, no. 5 (25), pp. 78–83.

3. Kazantsev M.N., Flegentov I.A., Zozulya S.N., Some specific features of repair documentation for overhaul of a multi-way plug valves (In Russ.), Oborudovanie i tekhnologii dlya neftegazovogo kompleksa, 2016, no. 3, pp. 68–72.

Anaerobic sulfate-reducing bacteria (SRB) make a special contribution to the bio-corrosion of oilfield equipment. A significant number of studies in petrochemistry are aimed at finding effective bactericides with respect to SRB and substances potentially improving complex anticorrosive compositions. Carrying out work in this direction, it seemed expedient to study the effect on the viability of the SRB of substances and reagents that are widely used in oil production. Conventionally, substances and reagents are divided into groups: bactericides, surface-active substances (surfactants), other reagents. In the experiments, the collection strain B-1799 Desulfovibrio desulfuricans was used as a test culture, providing 1360–1640 mg/l of hydrogen sulfide in 6–8 days of fermentation.

It has been established that among of the known bactericides only hydroxylamine hydrochloride suppresses CRP during the first hours of contact. The effect of formalin and hydrogen peroxide appears only after a few days. Other bactericides, as well as surfactants of various classes, do not affect the activity of SRB. The established fact is the suppression of the activity of SRB by extraneous aerobic microorganisms, which in these conditions manifest themselves as an optional microflora. Such a phenomenon was observed both when a specially grown aerobic fungal or bacterial culture was introduced into the medium with SRB, and a consortium of microorganisms spontaneously present in petrochemical reagents. In this regard, it can be assumed that the initial high microbiological purity of petrochemical reagents is not an important qualitative indicator, unless it determines the conditions and shelf life. On the contrary, with high contamination of the reagents used in the presence of SRB, the activity of bacteria and the synthesis of hydrogen sulfide are suppressed.

To determine the terms of safe operation of defects in pipe sections, it is necessary to calculate the number of cycles and the magnitude of pressure drops in main pipelines during operation.

Cycling calculation is carried out according to the number of starts of pumping units at the site (process switching) using data on the outlet pressure change of the pumping stations at the process site for a calendar year. The procedure for obtaining the calculated information on the cycling of loading implies the summation of the cycling at the output of all stations of the process site. The key feature of the technique is that the cycling is calculated within the process site of the main pipeline. The use of a single value of cycling for the process site in further calculations provides a margin of safe operation life of pipe section defects. With this approach, it is necessary to take into account the unique loading of each section, which is especially important for calculating the period of safe operation of defects.

The article considers the peculiarities of pressure drop consideration to calculate the cycling, and an analysis has been made of pressure drop consideration and the calculation results of cycling of loading for the existing pipeline. According to the results of the analysis, proposals were developed for improving the cycling determination algorithm, taking into account the loading with internal pressure of each section of the pipeline.

References

1. Varshitskiy V.M., Valiev M.I., Kozyrev O.A., Methodology of definition of retesting interval for a pipeline section (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2013, no. 3 (11), pp. 42–46.

2. Chepurnoy O.V., Myznikov M.O., Beseliya D.S. et al., Definition and registration of loading cycles of trunk oil pipeline (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2015, no. 3 (19), pp. 23–29.

3. Gumerov A.G., Zaynullin R.S., Yamaleev K.M., Roslyakov A.V., Starenie trub nefteprovodov (Aging pipe oil pipelines), Moscow: Nedra Publ., 1995, 218 p.

The operational reliability of pipeline systems in the conditions of Western Siberia is determined mainly by the ability of the pipeline structure to provide an operational position under the influence of destructive geological processes within the limits of acceptable values. Frost heaving of soils is most dangerous process for “warm” and “cold” pipelines, which is associated with huge forces and small absolute deformations because it don’t allow well-time diagnosis in high snow cover and absent of a planned-high-altitude position monitoring system. To date, design solutions for engineering protection of pipelines against frost heaving do not provide a standard level of reliability, which makes the problem of increasing the efficiency of engineering protection more important.

The authors divided the engineering protection methods into two groups: the first group reduces the heaving properties of the soil; the second group reduces forces from the side of heaving soil. The article shows the results of the numerical study of engineering protection methods of the second group. Analysis of the results showed an increased danger of local frost heaving with a length of no more than 21 m for main pipelines with a diameter of 530 to 1420 mm in comparison with longer ones. It proves the necessity of using the engineering protection on the all distance from the well with heaving soil to the well with non-heaving soil. Reducing the restrained capacity of adjacent non heaving soils reduces the stress-strain state in heaving areas. However it increases the risks of emerging and arch formation in engineering and geological conditions of Western Siberia and is not recommended for use. The use of soil bedding made of non-heaving materials under the bottom of pipe to reduce the forces and displacements from frost heaving can significantly reduce the stress-strain state of the pipeline. The numerical study of the bedding geometric parameters, carried out by the authors of the article, showed that the bedding made of materials more rigid than the soil of the ground should be deeper, and less rigid should be wider, due to the difference in protective properties.

References

1. Lazarev S.A., Pul'nikov S.A., Sysoev Yu.S., Diagnosing of extended spatially deformed sections of gas pipelines in the technical state and the integrity management system of Gazprom PJSC (In Russ.), Territoriya NEFTEGAZ, 2016, no. 4, pp. 106–115.

2. Lazarev S.A., Pul'nikov S.A., Sysoev Yu.S., Evaluation of the technical condition of the linear part of main gas pipelines in the zones of significant spatial deformation (In Russ.), Gazovaya promyshlennost', 2016, no. 9 (743), pp. 84–90.

3. Aleskerova Z.Sh., Pul'nikov S.A., Sysoev Yu.S., Estimation categories and criteria of main gas pipelines geotechnical condition under dynamicof adverse climatic processes (In Russ.), Izvestiya vuzov. Neft' i gaz, 2016, no. 6, pp. 30–35.

4. Gorkovenko A.I., Osnovy teorii rascheta prostranstvennogo polozheniya podzemnogo truboprovoda pod vliyaniem sezonnykh protsessov (Fundamentals of the theory of calculating the spatial position of an underground pipeline under the influence of seasonal processes): thesis of doctor of technical science, Tyumen', 2006.

5. Ivanov I.A., Ekspluatatsionnaya nadezhnost' magistral'nykh truboprovodov v rayonakh glubokogo sezonnogo promerzaniya puchinstykh gruntov (Operational reliability of main pipelines in the areas of deep seasonal freezing of heaving soils): thesis of doctor of technical science,Tyumen', 2002.

6. Mikhaylov P.Yu., Dinamika teplomassoobmennykh protsessov i teplosilovogo vzaimodeystviya promerzayushchikh gruntov s podzemnym truboprovodom (Dynamics of heat and mass transfer processes and thermal power interaction of freezing soils with an underground pipeline): thesis of candidate of physical and mathematical science, Tyumen', 2012.

7. Chikishev V.M., Issledovanie protsessa silovogo vzaimodeystviya lineynoy chasti truboprovodov s promerzayushchim gruntom (The study of the process of force interaction of the linear part of pipelines with freezing soil): thesis of candidate of technical science,Tyumen', 1999.

8. Aybinder A.V., Raschet magistral'nykh i promyslovykh truboprovodov na prochnost' i ustoychivost' (Calculation of strength and stability for main and field pipelines), Moscow: Nedra Publ., 1991, 287 p.

9. Kiselev M.M., Calculation of the normal forces of frost buckling foundations (In Russ.), Osnovaniya, fundamenty i mekhanika gruntov, 1961, no. 5, pp. 23–24.

10. Puskov V.I., Raschet normal'nykh sil moroznogo pucheniya gruntov na podoshve zhestkoy polosy s ogranichennoy podatlivost'yu (Calculation of the normal forces of frost heaving of soils on the sole of a rigid strip with limited compliance), Proceedings of NIIZhT, 1967, V. 13, pp. 141–150.

11. Shvets V.B., Elyuvial'nye grunty Urala kak osnovaniya fundamentov zdaniy i sooruzheniy (Eluvial soils of the Urals as the base of the foundations of buildings and structures): thesis of doctor of technical science, Moscow, 1967, 51 р.

12. Kuznetsov A.O., Practical computation method of slopes reinforced by horizontal bars of round cross-section (In Russ.), Izvestiya VNII gidrotekhniki im. B.E. Vedeneeva, 2017, V. 283, pp. 88–96.

Heavy oil production is characterized by low profitability and low oil recovery factor value. This is due to the necessity of using external power sources for the production process, on one hand, and on the other hand – due to the limited number of possibilities for using cheap resources in implementing efficient enhanced oil recovery methods. These problems can be successfully solved by utilizing energy-efficient multifunctional power systems. The design of suitable power equipment for cost-effective heavy oil production must be based on energy-saving and, preferably, energy-autonomous power systems. In this regard, for high-viscosity oil fields with low gas-solubility factor values and increased power consumption per unit of oil produced the technology of power generation from associated petroleum gas becomes economically attractive. Such systems present a combined solution to the problems defined and do not require external carbon dioxide sources. The autonomous trigeneration power can be adapted for the feedstocks available on-site (associated petroleum gas or the flue gases from nearby power plants if present), produce the heat and power necessary for heating the viscous oil and produce carbon dioxide to reduce oil viscosity and improve phase mobility. Implementing trigeneration power systems makes it economically viable to develop and apply thermal and gas injection methods for improving oil recovery. The power systems comprise, as a rule, a power module that uses the associated petroleum gas produced on-site, a carbon dioxide capture module and a compression module for obtaining liquid or supercritical carbon dioxide.

The structure of the autonomous trigeneration power system and the methodology of its implementation for oil production are presented. A comparison of the proposed autonomous power system with analogous overseas solutions is given.

References

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2. Kokorin A.O., Kuraev S.N., The Stern Review “The economics of climate change”, Moscow: Publ. of WWF Russia, 2007, 50 р.

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7. Kolesnikov V.V.. Naletov A.YU., Printsipy sozdaniya ehkotekhnologiy (Principles for creating eco-technologies), Moscow: Publ. of RCTU, 2008, 450 p.

8. Naletov V.A., Glebov M.B., Naletov A.YU., Methods of evolutionary synthesis of chemical-technological systems based on the information approach (In Russ.), Khimicheskaya tekhnologiya, 2010, no. 4, pp. 244–252.

9. Naletov V.A., Gordeev L.S., Glebov M.B., Naletov A.YU., Information-thermodynamic principle of the organization of chemical engineering systems (In Russ.), Teoreticheskie osnovy khimicheskoy tekhnologii = Theoretical foundations of chemical engineering, 2011, V. 45, no. 5, pp. 541–549.

10. Naletov V.A., Naletov A.YU., Glebov M.B., Carbon dioxide capture from flue gas in power cycle with trigeneration (In Russ.), Ehkologiya promyshlennogo proizvodstva, 2013, no. 4 (84), pp. 6–11.

The development of information technologies provided practical implementation of classical automation and control ideas and created prerequisites for the new economy concept with digital data representation, stimulating the creation of global information space as main production factor.

The article discusses system problems of digital economy in oil industry concept in accordance with the industry distinctive features. Evolution of system analysis enriched with the ideas of self-organizing systems, principles of the development and openness enabled qualitatively new approaches for the handling of uncertainty specific to the oil and gas production. Evolution nature of oil and gas generation, some specific uncertainties of oil industry objects and processes as well as main simulation approaches are considered.

Evolutional processes as the development basis have exerted strong influence upon the system analysis in technological processes management as well as the solution of multicriterion problems of economic-organizing management. The set of criteria itself evolved from mostly economic to risk oriented. The increase of the management decisions complexity caused the development of the technological processes management: from basic automate control systems to the complex systems provided full decision support at all levels of management hierarchy, from technological processes to the economic-organizing decisions accompanied with the increase of information technologies application.

The new automation stage of the production based on the principles of digital economy requires the integration of all available means and knowledge. The key role in the successful development of this project should be played by qualitatively new organization structures provided interdisciplinary approach and usage of scientific potential.

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3. The program “Tsifrovaya ehkonomika Rossiyskoy Federatsii” (Digital Economy of the Russian Federation), approved by the order of the Government of the Russian Federation dated July 28, 2017 No. 1632-p

4. Mirzadzhanzade A.Kh., Khasanov M.M., Bakhtizin R.N., Modelirovanie protsessov neftegazodobychi. Nelineynost’, neravnovesnost’, neopredelennost’ (Modelling of oil and gas production processes. Nonlinearity, disequilibrium, uncertainty), Moscow-Izhevsk: Publ. of Institute of Computer Science, 2004, 368 p.

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6. Abukova L.A., Dmitrievskiy A.N., Eremin N.A., Digital modernization of Russian oil and gas complex (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 10, pp. 54–58.

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One of the prime objectives in the area of improving the Gazporm Neft effectiveness is the completion of projects within an ambitiously tight period. It is the reference point for reducing projects implementation critical path. As a special case, the qualitative elaboration of the logistics support solutions at the early project stages is considered. This approach allows for consider mutual restrictions of the field facilities and logistics infrastructure and for create optimal integrated decisions. It enables not only assess the logistics cost but also evaluate the projects risks and uncertainties.

Within the proposed approach framework a new module of information system ERA:ISKRA is under development. «Conceptual and Logistic Engineering Integrator» will be able to thoroughly consider and rapidly adapt logistics options to the revisions off conceptual project. Thus, the robust decision is being elaborated, whereby the project parameters will be minimally sensitive to the factors that contribute to uncertainties. Furthermore, in the early stages of projects, global optimization becomes possible. The tasks of optimal logistics object allocation and trace of resources displacement will be solved. One of the most expensive items in logistics is the movement of soil materials from quarries to construction sites. To optimize this scheme is proposed to minimize the total amount of roads, the consumption of ground building material and the volume of material displacement. It also considers the priorities of objects mutual allocation and limits of area factor and relief.

Proposed approach allows not only to consider all possible logistic options and increase the estimation speed, but also to determine the optimal cost of supplies bearing in mind the project's risks and uncertainties. At the future construction phases, this will imply on-time delivery of full amount of logistic resources.

References

1. Batrashkin V.P., Ismagilov R.R., Panov R.A. et al., The integrated conceptual design as a tool of systematic engineering (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 12, pp. 80–83.

2. Bragin YU.V., Idea of robust design (In Russ.), Metody menedzhmenta kachestva, 2006, no. 12, pp. 18-24.

3. Beysenbi M.A., Mukataev N.S., Robust stability of a system with one input and one output in the class of catastrophes “hyperbolic umbilic” (In Russ.), Molodoy uchenyy, 2014, no. 2, pp. 107–117.

4. Vlasov A.I., Mozhchilʹ A.F., Technology overview: from digital to intelligent field (In Russ.), PROneftʹ, 2018, no. 3(9), pp. 68–74.

5. Ismagilov R.R., Kudryavtsev I.A., Maksimov Yu.V., Phases of conceptual design for field development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 12, pp. 66–70.

6. Ismagilov R.R., Maksimov Yu.V., Ushmaev O.S. et al., Integrated model for complex management of reservoir engineering and field construction (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 12, pp. 71–73.

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It's a common fact that gas-oil extraction influences all the components of the nature: atmospheric air, soils, surface and subsurface waters, including the bottom clays. In case of the Middle Ob where there’re a lot of swamps, water ecosystem suffers from the agricultural activities. On the one hand, oil production contributes to a change in the appearance of the surrounding landscapes as a result of the construction of various objects accompanying hydrocarbon production, and on the other, the geochemical background changes at the production sites. In the first case, changes can be measured in areal units. In the second case, a lot of geochemical analysis should be performed, the results of which draw certain conclusions. It should be emphasized that the obtained geochemical results require clarification, since in Western Siberia the background values of some chemical compounds initially exceed the maximum permissible concentrations established by the standards. At long-term developed fields, especially those whose exploitation began in Soviet times, background observations of the state of natural environments were not conducted. Such fields include the Vachimskoye oil-gas-condensate field, which has been developed for 30 years. Therefore, it is not always possible to correctly determine the degree of impact of the developed fields on the components of natural environments. To a certain extent, this gap can be resolved by analyzing the results of many years of geochemical observations of the state of natural environments.