A modern assessment of the technical and economic efficiency of an oil and gas project involves the construction of a certain economic and mathematical model of calculation, as well as an analysis of project criteria based on a variety of forecast economic indicators for the developed formations and the field as a whole. The automated system developed for this purpose served as the basis for theoretical and applied research in the field of economic modeling and modern information technologies. The article shows that with the help of modern information technologies it is possible to represent formalized knowledge (facts), the truth or falsity of which can be proved. In particular, these methods can be used in the digital economy of subsoil use. At the same time, it is supposed to analyze the processed information on the options for field development in order to solve the problem of synthesizing computational algorithms. Involvement of "systems engineers" in calculations significantly reduces the modeling process. The knowledge bases have been developed over the past two decades and are based on the experience of the technical and economic assessment of oil and gas fields both in our country and abroad. The system allows forecasting the technical and economic indicators of the study and development of hydrocarbon objects, taking into account various tax mechanisms, as well as assessing the value of deposits and the effectiveness of their development using fuzzy methods for assessing the risks of investment forecasts. It provides prompt and high-quality performance of technical and economic calculations for numerous options and sub-options with the choice of the optimal solution that determines the strategy and forecast for the development of oil production with different sources of funding. This development can be a good addition to the already existing software systems for the technical and economic assessment of the effectiveness of the development of oil and gas fields. It is relevant that the bipartite graphs that are part of the developed automated system make it possible to visually enter and correct technical and economic information on field development options.

References

1.  Ponomareva I.A, Bogatkina Yu.G., Eremin N.A., Kompleksnaya ekonomicheskaya otsenka mestorozhdeniy uglevodorodnogo syr'ya v investitsionnykh proektakh (A comprehensive economic evaluation of hydrocarbon fields in investment projects), Moscow: Nauka Publ., 2006, 134 p. 

2. Bogatkina Yu.G., Eremin N.A., Intelligent modeling technologies calculation of economic indicators for eval uation oil and gas deposits (In Russ.), Izvestiya Tul'skogo gosudarstvennogo universiteta. Nauki o Zemle, 2019, no. 3, pp. 344–355.

3. Dmitrievskiy A.N., Eremin N.A., Bogatkina Yu.G., Sardanashvili O.N., Assessment of technical and economic efficiency of investment projects of development of oil and gas deposits based on applica tion of fuzzy logic (In Russ.), Izvestiya Tul'skogo gosudarstvennogo universiteta. Nauki o Zemle, 2019, no. 3, pp. 340–348.

4. Bogatkina Yu.G., Stepankina O.A., Structure of intelligent interface in "Graph" logical system (In Russ.), Avtomatizatsiya, telemekhanizatsiya i svyaz' v neftyanoy promyshlennosti, 2015, no. 1, pp. 25–30.

5. Bashmakov A.I, Bashmakov I.A., Intellektual'nye informatsionnye tekhnologii (Intelligent information technology), Moscow: Publ. of Bauman University, 2005, 304 p.

6. Berezhnaya E.V., Berezhnoy V.I., Matematicheskie metody modelirovaniya ekonomicheskikh sistem (Mathematical methods for modeling economic systems), Moscow: Finansy i statistika Publ., 2006, 432 p.

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

8. Dunaev V.F., Shpakov V.A., Epifanova N.P. et al., Ekonomika predpriyatiy neftyanoy i gazovoy promyshlennosti (Economics of oil and gas industry), Moscow: Publ. of Gubkin Univetsity, 2008, 305 p. 

9. Konoplyanik A.A., Osnovnye vidy i usloviya finansirovaniya investitsionnykh proektov v neftegazodobyvayushchey promyshlennosti (The main types and conditions of financing investment projects in the oil and gas industry), Moscow: Publ. of Gubkin Univetsity, 2009, 62 p.

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

11. Trakhtengerts E.A, Stepin Yu.P., Andreev A.F., Komp'yuternye metody podderzhki prinyatiya upravlencheskikh resheniy v neftegazovoy promyshlennosti (Computer methods for supporting management decisions in the oil and gas industry), Moscow: SINTEG Publ., 2005, 592 p.

The article is devoted to the results of hydrocarbon prospects estimating on the Pechora sea shelf within the Gazprom Neft license areas. The area was clustered according to its geological and geophysical features. More than a hundred prospective objects are defined in six oil and gas complexes. Overall estimated hydrocarbon potential is more than 2,525 billion tons. The assessment is based on integration of regional 2D seismic data, new 3D seismic data from the three license areas, as well as core and outcrops data from adjacent areas. Based on sequence stratigraphic analysis, the reservoir properties and other parameters of the prospective objects were clarified. The promising objects are rated on the basis of key geological and geophysical indicators. Moreover the location for appraisal drilling for subsequent exploration is proposed. In addition to determining oil and gas content of Triassic, Permian and Carboniferous reservoirs, it is spoken in details about prospects of deep complexes. These complexes are reef traps of the Upper Franian, terrigenous reservoirs of the Middle Devonian and Prague stage, hypergene carbonate reservoirs of the Ovinparmian horizon (Lower Devonian) and Ordovician-Silurian carbonate rocks. Aiming to discovering giant fields on the Arctic shelf one of the technological challenges has been identified – drilling in difficult climatic conditions to prospective horizons at depths of more than 4.5-5.5 km. The proposed exploration and R&D program allows to determine the optimal well location and to solve non-standard technological challenges to achieve this ambitious goal.

References

1. Prishchepa O.M., Nefedov Yu.V., Ayrapetyan M.G., Hydrocarbon potential of the Arctic shelf sector of the north Timan-Pechora petroleum province on the results of regional researches (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2020, V. 15, no. 1, URL: http://www.ngtp.ru/rub/2020/4_2020.html

2. Bazhenova T.K., Petroleum source formations of the Russian ancient platforms and their petroleum potential (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2016, V. 11, no. 4, URL: http://www.ngtp.ru/rub/1/45_2016.pdf

3. Yur'eva Z.P., Position of oil pools in the sections of the Lower Devonian deposits (the Timan-Pechora province) (In Russ.), Geologiya nefti i gaza, 2015, no. 3, pp. 3–13. 

4. Zhemchugova V.A., Maslova E.E., Naumchev Yu.V., Sedimentatsionnaya model' nizhnedevonskikh otlozheniy severo-vostoka Khoreyverskoy vpadiny (Sedimentation model of the Lower Devonian deposits of the northeast of the Khoreyver depression), Collected papers “Geologiya i mineral'nye resursy Evropeyskogo Severo-Vostoka Rossii” (Geology and mineral resources of the European North-East of Russia), Proceedings of XVII Geological Congress of the Komi Republic, Part 3, Syktyvkar: Geoprint Publ., 2019, pp. 43–45.

5. 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 potential (In Russ.), Neftegazovoe delo, 2015, no. 5, pp. 20–44.

6. Vilesov A.P., Zakharova O.A., Zagranovskaya D.E. et al., The geological history and resource potential of Ovinparmian carbonate reservoirs of Dolginsko-Papaninskaya structural zone (Timan-Pechora Plate) (In Russ.), ProNeft', 2020, no. 4, pp. 24-33. 

7. Vashkevich A.A., Strizhnev K.V., Chekmarev S.I. et al., Experience of integration of potential field methods and surface geochemistry in the context of exploration planning within underexplored areas of the Bazhenov formation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 12, pp. 32–35.

A set of data on the trace element (TE) composition of oils from sedimentary basins of Kamchatka, oil outcrops of the Uzon volcano caldera, thermal springs and caldera lakes is analyzed. The correlation coefficients between the TE composition of these samples with the typical TE compositions of oil and other caustobioliths, biota, the Upper, Middle and the Lower continental crust are compared. Besides the general similarity of the compositions of the TE oils of the Uzon caldera and the basin oils of Kamchatka, a division of these oils into two groups was noted. The oils of the Uzon caldera and those closely associated with this zone differ from other basin oils of Kamchatka. The general specific feature of the TE composition of Kamchatka oils and thermal waters of the Uzon caldera is emphasized. In contrast to the average TE composition of oil and for oils from different oil and gas bearing basins of Russia, as well as for a number of oil samples from the giant Romashkinskoye field and its satellites and for oils of Shaim region of Western Siberia, the TE composition of oils from Kamchatka, the Uzon caldera, and thermal waters have a maximum correlation with the chemical composition of the Upper or Middle crust, whereas in all other cases the maximum correlation takes place with the chemical content of the Lower continental crust. This difference is interpreted within the framework of the model of the removal of oil components by an upward flow of young low-mineralized waters being of dehydration products. Under conditions of higher deep temperatures in Kamchatka, dehydration reactions occur at shallower depths, and the fluid flow bears a mark of shallower horizons of the Earth's crust. Physicochemical properties and hydrocarbon composition of Kamchatka oils: low content of V and Ni – less than 10 ppm, and nickel metallogeny (V/Ni<1) indicate that these oils belong to the class of early catagenetic fluids, which are formed from an organic matter in zones of late protocatagenesis or early mesocatagenesis and are stored in complex traps of a combined type.

References

1. Fursenko E.A., Kashirtsev V.A., Kontorovich A.E., Fomin A.N., Naphthides of continental hydrotherms (Uzon, Yellowstone, New Zealand): Geochemistry and genesis (In Russ.), Geologiya i geofizika = Russian Geology and Geophysics, 2014, V. 55, no. (5–6), pp. 918–930.

2. Kontorovich A.E., Bortnikova S.B., Karpov G.A. et al., Uzon volcano Caldera (Kamchatka): A unique natural laboratory of the present-day naphthide genesis (In Russ.), Geologiya i geofizika = Russian Geology and Geophysics, 2011, V. 52, no. 8, pp. 986–990.

3. Beskrovnyy N.S., Lebedev B.A., Oil development in the caldera of the Uzon volcano in Kamchatka (In Russ.), DAN SSSR, 1971, V. 201, no. 4, pp. 953–956.

4. Dobretsov N.L., Lazareva E.V., Zhmodik S.M. et al., Geological, hydrogeochemical, and microbiological characteristics of the oil site of the Uzon Caldera (Kamchatka) (In Russ.), Geologiya i geofizika = Russian Geology and Geophysics, 2015, V. 56, no. (1–2), pp. 56–88.

5. Vinogradova T.L., Punanova S.A., Naphthydes of Eastern Kamchatka and the Guyamas California basin (In Russ.), Aktual'nye problemy nefti i gaza, 2017, no. 3 (18), URL:  http://oilgasjournal.ru/issue_18/vinogradova.html

6. Simoneit B.R.T., Deamer D.W., Kompanichenko V., Characterization of hydrothermally generated oil from the Uzon caldera, Kamchatka, Appl. Geochem., 2009, no. 24, pp. 303–309.

7. Taylor S.R., McLennan S.M., The continental crust: Its composition and evolution, Blackwell, Oxford, 1985, 312 p. 

8. Rudnick R.L., Gao S., Composition of the continental crust, Treatise on Geochemistry, 2003, V. 3, pp. 1–64, DOI: 10.1016/B0-08-043751-6/03016-4

9. Temyanko M.B., Kudryavtseva E.I., Solov'eva I.L. et al., The composition of aromatic hydrocarbons in East Kamchatka oils (In Russ.), Geokhimiya, 1990, no. 6, pp. 790–796.

10. Bazhenova O.K., Arefiev O.A., Frolov E.V., Oil of the volcano Uzon caldera, Kamchatka, Org. Geochem., 1998, V. 29, no. (1–3), pp. 421–428.

11. Kudryavtseva E.I., Yakutseni S.P., Smurov L.L., Metals in the oils of Kamchatka and Chukotka (In Russ.), Doklady Akademii nauk, 1993, V. 331, no. 4, pp. 477–479. 

12. Yakutseni S.P., Rasprostranennost' uglevodorodnogo syr'ya, obogashchennogo tyazhelymi elementami-primesyami. Otsenka ekologicheskikh riskov (Prevalence of hydrocarbon feedstock enriched with heavy impurities. Environmental risk assessment), St. Petersburg: Nedra Publ., 2005, 372 p.

13. Punanova S.A., Rodkin M.V., Comparison of the contribution of differently depth geological processes in the formation of a trace elements characteristic of caustobiolytes (In Russ.), Georesursy = Georesources, 2019, V. 21 (3), pp. 14–24.

14. Shpirt M.Ya., Punanova S.A., Oils and combustible shales as a raw for potentially trace elements producing (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 4, pp. 58–62.

15. Varfolomeev S.D., Karpov G.A., Sinal G.A. et al., The youngest natural oil on earth (In Russ.), Doklady Akademii nauk = Doklady Chemistry, DAN, 2011, V. 438, no. 3, pp. 345–347.

16. Rodkin M.V., Rundkvist D.V., Punanova S.A., The relative role of lower and upper crustal processes in the formation of trace element compositions of oils (In Russ.), Geokhimiya, 2016, no. 11, pp. 1025–1031.

 

 

Justification of integrated interpretation models that take into account a wide range of distorting factors, often contained in the rock itself, including the influence of development processes on the open-pit GIS readings, contributes to increasing the reliability of quantitative estimates of calculation parameters, the effectiveness of searching for missed hydrocarbon deposits, and rational planning of geological and technical measures, which is most relevant in the conditions of old producing provinces. Oil companies today continue to develop a large number of fields discovered, explored and drilled in the last century. The main well stock of such fields, as a rule, has been studied by a limited set of “standard” logging methods, and the laboratory-studied core is not very representative and / or analyzed incompletely. Extreme geological and technical conditions for drilling wells that penetrate, for example, the Mesozoic-Cenozoic sediments of the Eastern Ciscaucasia and complex heterogeneous reservoirs enclosed in them, often lead to the need for additional iterations in interpretive petrophysical algorithms. To obtain adequate geological and hydrodynamic models, it is necessary to have close to true parameters obtained using common methods of interpretation of the initial data, and to compare the operation of neighboring wells – sections with comparable parameters. The priority tasks are: selection of well logging methods with minimal sensitivity to various well conditions; development of integrated interpretation models adapted for different completeness of logging complexes and wells drilled in disparate time periods, as well as taking into account the "non-standard" distorting influence of development factors on the desired geophysical parameters. In this article, special attention is paid to such factors distorting the well logging readings as the gas content and the phase state of the fluids saturating the reservoirs.

References

1. Vendel'shteyn B.Yu., Issledovanie razrezov neftyanykh i gazovykh skvazhin metodom sobstvennykh potentsialov (Research of sections of oil and gas wells by the method of intrinsic potentials), Moscow: Nedra Publ., 1966, 206 p.

2. Pirson S.J., Handbook of well log analysis for oil and gas formation evaluation, Prentice-Hall, 1963.

3. Braylovskaya A.A., Oks L.S., Study on the distorting effects of up-to-date drilling muds on well logs and invaded zone parameters of terrigenous mesozoic sediments in East Stavropol region (In Russ.), Karotazhnik, 2019, no. 4 (298)., pp. 3–17.

4. Luk'yanov E.E., Strel'chenko V.V., Geologo-tekhnologicheskie issledovaniya v protsesse bureniya (Geological and technological research in the process of drilling), Moscow: Neft' i gaz Publ., 1997, 688 p.

5. Golovatskaya I.V., Gulin Yu.A., Methodology for determining the porosity of gas-bearing rocks by the GGL, NL, SP complex (In Russ.), Geologiya nefti i gaza, 1982, no. 12, pp. 6–9. 

6. Aleksandrov B.L., Kompleksnoe izuchenie yurskikh otlozheniy Vostochnogo Predkavkaz'ya v svyazi s otsenkoy ikh kollektorskikh svoystv i neftegazonasyshchennosti (Comprehensive study of Jurassic deposits of the Eastern Ciscaucasia in connection with the assessment of their reservoir properties and oil and gas saturation): thesis of candidate of geological and mineralogical science, Groznyy, 1968.

7. Chumicheva A.A., Kharchenko S.I., Development of a unified methodology of evaluation and capacitive properties of the deposits of the East of Stavropol territory (In Russ.), Nauchno-tekhnicheskiy vestnik OAO NK “Rosneft”, 2014, V. 35, no. 2, pp. 56–59. 

8. Shnurman I.G., Izuchenie terrigennykh kollektorov Predkavkaz'ya po rezul'tatam geofizicheskikh issledovaniy skvazhin (The study of Ciscaucasus terrigenous reservoirs on the results of well logging), Krasnodar: Prosveshchenie-Yug Publ., 2003, 397 p.

The work objective was an analysis for the petroleum prospectivity of a core from the Marcellus Formation of Western Pennsylvania, USA. In accordance with the investigation results, sample groups were delineated based on TOC (Total Organic Carbon) and total hydrocarbon content measurements of the analyzed core and the most prospective interval for further development was marked out. Core analysis on a Marcellus TST sequence overlain by undetermined sequence Marcellus core was done using pyrolysis and SEM XRF measurements together with GR (Gamma Ray), ChemoGR (calculated from potassium, thorium and uranium), Porosity and PHIE (Effective Porosity) logging. Oil saturation was measured using both Classical Pyrolysis and HAWK-PAM methods. HAWK Petroleum Assessment Method is advanced multiramp/multizone pyrolysis method that utilizes five zones using multiple ramp and isotherm routines assigned during a single sample analysis. Such program is utilized to generate five petroleum peaks – four on oil fractions and one on kerogen. Based on the aforementioned analyses, it was evident that the sweet spot for petroleum prospectivity in the analyzed Marcellus Formation core is the 1940,75–1942,95 m. The efficiency of the HAWK-PAM pyrolysis method is shown for determination of the sweet spot intervals that is particularly important for the development of hard-to-recover unconventional reservoirs like the Marcellus formation in USA or the Bazhenov formation in Russia.

References

1. Dow W.G., How plant and animal remains become oil and gas: A geochemical perspective, AAPG Search and Discovery, Article no. 40830, 2011, URL: http://www.searchanddiscovery.com/documents/2011/40830dow/ndx_dow.pdf?q=%2BauthorStrip%3Adow+-isMeet...

2. Jarvie D.M, Baker D.R., Application of the Rock-Eval III oil show analyzer to the study of gaseous hydrocarbons in an Oklahoma gas well: 187th ACS National Meeting, St. Louis, Missouri, April 8–13, 1984, URL: http://wwgeochem.com/references/JarvieandBaker1984 ApplicationofRock-Evalforfindingbypassedpayzones.pdf

3. Jarvie D.M., Shale resource systems for oil and gas. Part 1. Shale-gas resource systems, In: Shale reservoirs. Giant resources for the 21st century: edited by Breyer J.A, AAPG Memoir 97, 2012, pp. 69–87.

4. Jarvie D.M., Shale resource systems for oil and gas. Part 2. Shale-oil resource systems, In: Shale reservoirs. Giant resources for the 21st century: edited by Breyer J.A, AAPG Memoir 97, 2012, pp. 89–119.

5. Peters K.E., Guidelines for evaluating petroleum source rock using programmed pyrolysis, AAPG Bull., 1986, V. 70, no. 3, pp. 318–329.

6. Loucks R.G., Reed R.M., Ruppel S.C., Hammes U., Spectrum of pore types and networks in Mudrocks and a descriptive classification for matrix-related mudrock pores, AAPG Bull., 2012, V. 96, no. 6, p. 1071–1098.

7. Buller D., Hughes S.N., Market J. et al., Petrophysical evaluation for enhancing hydraulic stimulation in horizontal shale gas wells, SPE-132990-MS, 2010.

8. Jarvie D.M., Unconventional shale-gas systems: The Mississippian Barnett Shale of north-central Texas as one model for thermogenetic shale-gas assessment, AAPG Bull., 2007, V. 91, no. 4, pp. 475–499.

Currently, the share of low-permeability oil and gas reservoirs among newly discovered fields is steadily growing and even becoming decisive. In this regard, analytical studies of nonlinear filtering processes are of particular importance. As shown in the paper, the nonlinearity of this equation fundamentally changes the form of analytical dependencies describing the form of pressure curves during well-test analysis and this means that the use of currently accepted methods for processing field research data will inevitably lead to erroneous conclusions regarding the characteristics of low-permeability productive layers. Based on the analysis of the properties of generalized self-similar solutions, the dependence of the well production rate with time at a constant value of depression is obtained, as well as the time dependence of the pressure in the wellbore when it is put into operation with a constant production rate. It is shown that under the Darcy law with a power-law dependence of the filtration rate on the pressure gradient, the flow rate of the well with constant depression, and the pressure in the wellbore with constant selection of the reservoir liquids are represented by power functions of time. Compared to the logarithmic functions of time, power-law functions are characterized by faster rates of change over time, which means that in low-permeability reservoirs, quasi-stationary well operation modes are almost impossible. Such features of the operation of production wells in low-permeability reservoirs may be erroneously evaluated as evidence of the existence of limited-sized oil-saturated lenses around these wells. From the physical point of view, this feature is due to the fact that the size of the depression funnel around the borehole with a power-law form of the Darcy law grows very slowly with time and, moreover, there is a moving boundary separating the region of the perturbed filtration flow around the borehole from resting reservoir fluid away from the well.

The analytical dependences presented in the work were compared with the results of the numerical solution of the corresponding problems, and such a comparison confirmed the validity of the obtained dependencies. Thus, the analytical results obtained in the work allow to explain some features of low-permeability reservoirs development, and more correctly interpret the results of well-test analysis in such reservoirs.

References

1. Baykov V.A., Galeev R.R., Kolonskikh A.V., Makatrov A.K. et al.,  Nonlinear filtration in low-permeability reservoirs. Analisys and interpretation of laboratory core examination for Priobskoye oilfield (In Russ.), Nauchno-tekhnicheskiy vestnik OAO “NK “Rosneft'”, 2013, no. 2, pp.  8–12.

2. Xu J., R., Jiang L., Xie M. Yang et al., Transient pressure behavior for dual porosity low permeability reservoir based on modified Darcy’s equation, SPE-153480-MS, 2012, https://doi.org/10.2118/153480-MS. 

3. Barenblatt G.I., Entov V.M., Ryzhik V.M., Dvizhenie zhidkostey i gazov v prirodnykh plastakh (Movement of liquids and gases in natural reservoirs), Moscow: Nedra Publ., 1982, 211 p.

4. Rebinder P.A., Kusakov M.M, Zinchenko K.E., Surface phenomena in filtration processes (In Russ.), Doklady AN SSSR, 1940, V. 28, no. 5, pp. 42–49. 

5. Ar'e A.G., Fizicheskie osnovy fil'tratsii podzemnykh vod (Physical principles of groundwater filtration), Moscow: Nedra Publ., 1984, 101 p.

6. Carslaw H., Jaeger J., Conduction of heat in solids, Oxford University Press, USA, 1959, 510 p.

7. Courant R., Hilbert D., Methods of mathematical physics, V. 2: Partial differential equations, Wiley, 1966, 811 p.

Wave stimulation techniques to enhance oil recovery and/or remove formation damage in the near wellbore zone have been attracting interest in oil industry practice in recent years. It is known from literature that the technique has been successful in some cases, however, to-date, there are several controversial and inconclusive issues about the technology. The main point at issue is the physical mechanism of the wave stimulation process and its effect on different reservoir rocks. To gain greater insight into the process and to evaluate the efficiency of the wave stimulation technique in carbonate and sandstone reservoirs, Tatneft PJSC has carried out a wide-scale field experiment in the own producing assets. The experiment was carried out over a period of two years involving 23 wells on three pilot blocks. The wells adjacent to those with the waves’ generators were equipped with downhole gauges to measure pressure, production rate (or injectivity), and water cut of the wellstream. The field experiment comprised two stages: acquisition and analysis of production and injection wells’ data in absence of wave stimulation, and the same after starting and operation of generators. Reservoir flow capacity, viscosity and density of degassed oil at both stages were analyzed. To evaluate the effect of wave stimulation, the RTA (Rate Transient Analysis) provided by the Kappa Topaze software was applied instead of the commonly used DCA (Decline Curve Analysis) approach. Change in production rate after wave stimulation was used as the main criterion. Algorithm of determination of this parameter based on interpretation results was offered. The field experiment yielded the following results: in the Kynovskian-Pashiyan reservoirs with high water cut, oil production rates increased by some 6%; in addition, a significant increase in degassed oil viscosity was recorded suggesting that the by-passed oil was mobilized. In the Tournaisian reservoirs with low water cut developed at low borehole pressure, production rates did not change. Comparative analysis of pressure buildup curves did not show a somewhat pronounced change in the reservoir flow capacity.

References

1. Napol'skaya R.N., A promising technologies for stimulation of oil based on the wave phenomena (In Russ.), Neftegazovye tekhnologii i novye materialy. Problemy i resheniya, 2018, no. 7(12), pp. 168–174.

2. Dubinskiy G.S., Chibisov A.V., Ganiev O.R. et al., Planning of technologies for stimulation wells and enhance in oil recovery with use of wave processes and the resonance in productive layers (In Russ.), Neftegazovye tekhnologii i novye materialy. Problemy i resheniya, 2016, no. 5 (10), pp. 186–196.

3. Ganiev O.R., Ganiev R.F., Ukrainskiy L.E., Rezonansnaya makro- i mikromekhanika neftyanogo plasta. Intensifikatsiya dobychi nefti i povysheniya nefteotdachi. Nauka i praktika (Resonant macro- and micromechanics of an oil reservoir. Enhanced oil production and enhanced oil recovery. Science and practice), Moscow – Izhevsk: Institute of the computer science, 2014, 256 p.

4. Kuznetsov O.L., Dyblenko V.P., Sharifullin R.Ya., Tufanov I.A., Innovatsionnye volnovye tekhnologii i ikh ispol'zovanie dlya povysheniya effektivnosti razrabotki neftegazovykh mestorozhdeniy (Innovative wave technologies and their use to improve the efficiency of oil and gas field development), Collected papers “Elastic wave effect on fluid in porous media, Proceedings of III International conference, Moscow, 2012, pp. 4–7.

5. Barabanov V.L., Nikolaev A.V., Problema spektra dominantnykh chastot pri seysmicheskom vozdeystvii na neftyanye zalezhi (The problem of the spectrum of dominant frequencies during seismic impact on oil deposits), Collected papers “Elastic wave effect on fluid in porous media, Proceedings of III International conference, Moscow, 2012, pp. 30–33.

6. Barskaya E., Tukhvatullina A., Ganeeva Y., Yudupova T., Influence of ultrasonication on the dispersed structure of the crude oils, Collected papers “Elastic wave effect on fluid in porous media, Proceedings of III International conference, Moscow, 2012, pp.39–42.

7. Svalov A.M., Conditions of effective application of technologies of shock-wave impact on productive formations (In Russ.), Tekhnologii nefti i gaza, 2019, no. 5, pp. 53–57.

8. Seysmicheskoe vibrovozdeystvie na neftyanuyu zalezh' (Seismic vibration impact on an oil reservoir): edited by Sadovskiy M.A., Nikolaev A.V., Moscow: Publ. of UIPE RAS, 1993, 240 p.

9. Simonov B.F., Cherednikov E.N., Serdyukov S.V. et al., The technology of volumetric wave action on oil and gas deposits to enhance hydrocarbon recovery (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1998, no. 4, pp. 42–44.

10. Kostrov S.A., Wooden W.O., Roberts P.M., In situ seismic shockwaves stimulate oil production, Oil and Gas Journal, 2001, V. 99(36), pp. 47–52.

11. Iktisanov V.A., Shkrudnev F.D., Oil recovery factor taking into account natural reserves replacement (In Russ.), Energeticheskaya politika, 2020, no. 9 (151), pp. 34–43. 

12. Iktisanov V.A., Sakhabutdinov R.Z., Evaluation of effectiveness of EOR and bottomhole treatment technologies using rate transient analysis (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 5, pp. 72–76.

13. Allain O. et al., Dynamic flow analysis, KAPPA, 2007.

Review of long-term researches on acidizing of production and injection wells using solid acid compositions based on sulfamic acid, that were carried out at the National University of Oil and Gas Gubkin University, is presented in this paper. Sulfamic acid is formed by the interaction of carbamide and oleum at 60–70°C and is produced in the form of non-adsorbing water crystals. The behavior of the acid is associated with the formation of zwitter-ions in water, which contribute to activity increase of synthetic surfactants. Sulfamic acid has advantages over hydrochloric acid; it has a slower reaction rate with carbonate rock and is less aggressive towards metal surfaces of production equipment. Sulfamic acid produces less viscous oil-acid emulsions that do not form sludge deposits. Injection of sulfamic acid solutions into oil-saturated porous medium under thermobaric conditions of the formation leads to higher phase permeability to the displacing fluid than for hydrochloric acid. Based on the obtained regularities of interaction of sulfamic acid with rock, formation fluids and damaging agents of bottomhole formation zone, solid acid compositions for treating wells operating low-temperature depleted formations were developed. The acid treatments results confirmed the effectiveness of multistage technologies based on the application of the solid acid compositions. Previous studies showed that sulfamic acid is prone to hydrolysis at temperatures above 60°C; however, the developed technologies allow the use of the acid compositions at higher temperatures.

Acknowledgment. This work was supported by the Ministry of Science and Higher Education of the Russian Federation under agreement No. 075-15-2020-936 within the framework of the development program for a world-class Research Center.

References

1. Maksin V.I., Standritchuk O.Z., Kinetics and mechanism of hydrolysis of sulfamic acid (In Russ.), Zhurnal fizicheskoy khimii = Russian Journal of Physical Chemistry A, 1995, V. 69, no. 6, pp. 974–979.

2. Amerkhanova Sh.K., Shlyapov R.M., Uali A.S., Features of the dissociation process of sulfamic acid in aqueous-organic solvents (In Russ.), Vestnik Voronezhskogo gosudarstvennogo universiteta. Seriya: Khimiya. Biologiya. Farmatsiya, 2014, no. 3, pp. 5–8.

3. Amiyan V.A., Ugolev V.S., Fiziko-khimicheskie metody uvelicheniya proizvoditel'nosti skvazhin (Physico-chemical methods to increase the productivity of wells), Moscow: Nedra Publ., 1970, 280 p.

4. Magadova L.A., Tsygankov V.A., Pakhomov M.D., Yunusov T.I., Development of thermostable dry acid composition based on sulfamic acid (In Russ.), Trudy Rossiyskogo gosudarstvennogo universiteta nefti i gaza im. I.M. Gubkina, 2019, no. 4 (297), pp. 186–198.

5. Patent RU 2101482 C1, MPK E 21 V 43/27, Acid compound for treating terrigenous reservoirs, Inventors: Magadov R.S., Silin M.A., Gaevoy E.G., Rud' M.I., Magadova L.A., Chekalina G., Maksimova S.V., Poddubnyy Yu.A., Galeev F.Kh., Dyabin A.G., Kan V.A., Sorkin A.Ya.

6. Magadova L.A., Davletshina L.F., Pakhomov M.D., Davletov Z.R., Terrigenous reservoirs rock dissolution investigation in the fluorinated acid compounds (In Russ.), Territoriya Neftegaz, 2015, no. 12, pp. 94–100.

7. Silin M.A., Magadova L.A., Tolstykh L.I. et al., Aspects of interaction of surfactant-acid compositions at phase boundary with hydrocarbons (In Russ.), Zhurnal prikladnoy khimii = Russian Journal of Applied Chemistry, 2019, V. 92, no. 12, pp. 1732–1741.

8. Magadova L.A., Davletshina L.F., Gubanov V.B. et al., Research of specific aspects in interaction between oil and acid compositions in porous medium (In Russ.), Trudy Rossiyskogo gosudarstvennogo universiteta nefti i gaza im. I.M. Gubkina, 2017, no. 4(289), pp. 132–142.

9. Davletshina L.F., Tolstykh L.I., Davletov Z.R., Vlasova V.D., Study of interfacial tension at the boundary between hydrocarbon phase and acid compositions based on sulfamic acid and surfactants (In Russ.), Territoriya Neftegaz, 2017, no. 9, pp. 20–26.

10. Ganeeva Yu.M., Barskaya E.E., Okhotnikova E.S. et al., Distribution of paraffin hydrocarbons and asphaltenes in acidic water-oil emulsion (In Russ.), Neftekhimiya = Petroleum Chemistry, 2018, V. 58, no. 6, pp. 742–750.

11. Silin M.A., Magadova L.A., Davletshina L.F. et al., Features of interfacial phenomena at the phase boundary between hydrocarbon systems and acids (In Russ.), Khimiya i tekhnologiya topliv i masel, 2020, no. 2, pp. 25–30.

12. Amiyan V.A., Ugolev V.S., Kuznetsov G.N., Physico-chemical methods to increase the productivity of wells (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1969, no. 10, pp. 62–65.

13. Silin M.A., Magadova L.A., Davletshina L.F. et al., Research of current corrosion inhibitors action in acid systems (In Russ.), Praktika protivokorrozionnoy zashchity, 2016, no. 4 (82), pp. 22–30.

14. Magadova L.A., Davletshina L.F., Efanova O.Yu., Poteshkina K.A., The problem of investigation of coiled tubing corrosion during acid treatment (In Russ.), Tekhnologii nefti i gaza, 2012, no. 2, pp. 12–15.

15. Silin M.A., Magadova L.A., Davletshina L.F., Efanova O.Yu., Stimulation of terrigenous reservoirs through producing wells annulus (In Russ.), Neftepromyslovoe delo, 2012, no. 7, pp. 27–30. 

16. Davletshina L.F., Magadova L.A., Silin M.A.  et al., Acid treatment of injection wells. Old problems - new solutions (In Russ.), Territoriya Neftegaz, 2009, no. 3, pp. 38–41.

17. Davletshina L.F., Gus'kova I.A., Garipova L.I., Akhmetshina A.S., Integrated approach to the development of technology of iInjection well bottomhole treatment and the technology efficiency evaluation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 7, pp. 40–42.

This study investigates the polymer solutions used in water shut-off control of production wells and polymer flooding of Santa Cruze reservoir located in Republic of Cuba. The reservoir is characterized by early water breakthrough and therefore application of chemical reagents is required to decrease the content of produced water and gases from production wells. The aim of this study was to reveal the influence of mineral salts on the rheology of polymer solutions based on two different industrial trademarks: Seurvey R1 and Softpusher. The hydrochemical composition and physical properties of formation water samples from Santa Cruze reservoir revealed domination of sodium and potassium cations and chloride anion. The water hardness (8.3 mg-eq./L) was calculated basing on the content of calcium and magnesium cations. It was revealed that Suervey R1 has a higher viscosity, which is in consistent with its molecular mass. In general, investigation of polymer solutions, which were prepared with distilled water, shows better rheological performance than solutions based on formation water samples. This is due to sensitivity of polyacrylamide (PAA) to the ion forces of solvents. The swelling degree is maximum in case of distilled water and sharply decreases with addition of salt content. The Softpusher polyacrylamide solutions were more salt-tolerated than Seurvey R1 polyacrylamide solutions, as Softpusher PAA has less branched structures in contrast with high-molecular and more branched Seurvey R1 polymer. Increasing viscosity of dispersion medium inhibits the precipitation rate of dispersed particles. Thus, the rheology and sedimentation stability of dispersion are improved due to polyacrylamide flocculation.

References

1. Radchenko S.S., Novakov I.A., Radchenko P.S. et al., Interaction of aluminoxane particles with weakly charged cationic polyelectrolytes, Journal of Applied Polymer Science, 2011, V. 121, no. 1, pp. 475–482.

2. Lake L.W., Enhanced oil recovery, Prentice Hall, Cop., 1989, 550 p.

3. Fan V.A., Razrabotka sostava dlya tekhnologii PAV-polimernogo zavodneniya primenitel'no k usloviyam nizhnego miotsena mestorozhdeniya Belyy Tigr (Development of a composition for surfactant-polymer flooding technology applied to the conditions of the Lower Miocene of the White Tiger field): thesis of candidate of technical science, Moscow, 2017. 

4. Idahosa P.E.G., Oluyemi G.F., Oyeneyin M.B., Prabhu R., Rate-dependent polymer adsorption in porous media, Journal of Petroleum Science and Engineering, 2016, V. 143, pp. 65–71.

5. Al-Hashmi A.R., Luckham P.F., Grattoni C.A., Flow-induced-microgel adsorption of high-molecular weight polyacrylamides, Journal of Petroleum Science and Engineering, 2013, V. 112, pp. 1–6.

6. Ruzin L.M., Morozyuk L.M., Metody povysheniya nefteotdachi plastov (teoriya i praktika) (EOR methods (theory and practice)), Ukhta: Publ. of USTU, 2014, 127 p.

7. Mukhamatdinov I.I., Aliev F.A., Sitnov S.A. et al., Study of rheological behavior of systems ‘polymer solution – rocks’ (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 11, pp. 121–123.

8. Sosa Akosta A., Mukhamatdinov I.I., Solodov V.A., Vakhin A.V., Investigation of physicochemical properties of polyacrylamidesmers (In Russ.), Vestnik Kazanskogo tekhnologicheskogo universiteta, 2018, V. 21, no. 8, pp. 52–56.

9. Mukhamatdinov I.I., Aliev F.A., Sosa Acosta A., Vakhin A.V., A new approach for measuring rheology of polymer solutions in reservoir conditions, Journal of Petroleum Science and Engineering, 2019, V. 181, pp. 106–160.

10. Mukhamatdinov I.I., Sosa Akosta A., Vakhin A.V., Solodov V.A., The influence of pressure on the interfacial tension of polyacrylamides (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 6, pp. 90–92.

11. Aquilanti V., Cappelletti D., Pirani F., Range and strength of interatomic forces: dispersion and induction contributions to the bonds of dications and of ionic molecules, Chemical Physics, 1996, V. 209, pp. 299–311.

12. Kavalerskaya N.E., Ferapontov N.B., The behavior of cross-linked polyacrylamide in solutions of low molecular weight electrolytes (In Russ.), Sorbtsionnye i khromatograficheskie protsessy, 2009, V. 9, no. 3, pp. 433–440.

13. Telin A.G., Zaynetdinov T.I., Khlebnikova M.E., Study of the rheological properties of water-swellable polyacrylamide FS 305 for the development of technologies for water shut-off works at oil wells (In Russ.), Proceedings of Mavlyutov Institute of Mechanics, 2006, pp. 207–223.

The paper summarizes the results of laboratory experiments performed on core samples of two carbonate reservoirs of the Republic of Tatarstan with modeling of real in-situ stresses to assess the dependence of permeability on a cyclic change in pore pressure. Each experiment consisted of 14 pressure stages with two changes in the direction: primary depletion, followed by increase in pressure, and then secondary depletion. At each stage, the permeability was measured for the saturating fluid, and the dynamic values of Poisson's ratio and Young's modulus were obtained by the acoustic method. The behavior of permeability depends both on the initial properties of the samples and saturating fluid. 'Looser' samples with the lowest initial values of Young's modulus showed the strongest permeability reduction during primary depletion. For samples with the highest Young's modulus and the poorest initial reservoir properties, the permeability changed slightly with a decrease in pore pressure. For water-saturated samples, reservoir compaction was recorded as the result of the cyclic change in pressure, most likely associated with plastic deformation of carbonate rock under the influence of water. For hydrocarbon-saturated samples, an increase in permeability during the cyclic geomechanical treatment (CGT) was obtained, ranging from 20% to 3.5 times. For a number of samples, during the increase in pore pressure, an evidence of the formation of a tensile fracture (equivalent to the hydraulic fracturing process) was noted. In all those cases, the value of the fracturing pressure was significantly lower than theoretically estimated which indicates a decrease in rock strength as a result of the previous pressure depletion.

The experimental results were used in flow simulations on sector models of two reservoir elements. Taking into account the dependence of permeability on pressure leads to more heterogeneous distributions of the reservoir pressure and oil recovery. It is shown that in order to assess the potential effect of CGT, appropriate consideration of reservoir compartmentalization and heterogeneity is important. For the sector model of the element with favorable parameters, an increase by 24.6% in cumulative oil production over 10 years was achieved due to the integrated use of CGT.

References

1. Patent SU1609978A1, Method of treating bottom-hole zone of formation, Inventors: Bakirov E.A., Zakirov S.N., Shcherbakov G.A., Kondrat R.M., Panteleev G.V., Fedoseev A.P., Shandrygin A.I.

2. Khristianovich S.A., Kovalenko Yu.F., Kulinich Yu.V., Karev V.I., Increase the productivity of oil wells using the geoloosening (In Russ.), Neft' i gaz Evraziya, 2000, no. 2, pp. 90–94.

3. Patent RU2620099C1, Method of increasing productivity of development wells and injection capacity of injection wells, Inventors: Zakirov S.N., Drozdov A.N., Zakirov E.S., Drozdov N.A., Indrupskij I.M., Anikeev D.P., Ostapchuk S.S. 

4. Patent RU2645684C1, Method of directional loading of the plast, Inventors: Klimov D.M., Karev V.I., Kovalenko Yu.F., Titorov M.Yu.

5. Patent RU2285794C1, Well bottom zone treatment method, Inventors: Karev V.I., Klimov D.M., Kovalenko Ju.F., Kulinich Ju.V., Samokhvalov G.V., Titorov M.Ju.

6. Zakirov S.N., Razrabotka gazovykh, gazokondensatnykh i neftegazokondensatnykh mestorozhdeniy (Development of gas, gas condensate and oil-and-gas condensate fields), Moscow: Struna Publ., 1998, 628 p.

7. Zakirov S.N., Drozdov A.N., Zakirov E.S. et al., Technical and technological aspects of geomechanical impact on the reservoir (In Russ.), Neftegaz.RU, 2018, no. 6, pp. 24–29.

8. Zakirov S.N., Drozdov A.N., Alekseev B.G., Kolobanov A.V., Natural manifestations of geomechanical processes (In Russ.), Nedropol'zovanie XXI vek, 2018, no. 3, pp. 72–77.

9. Khashper A.L., Aminev T.R., Fedorov A.I., Zhonin A.V., Research of dependence of rock permeability on its stress-strain state (In Russ.), Geologicheskiy vestnik, 2019, no. 1, pp. 133–140

10. Karev V.I., Vliyanie napryazhenno-deformirovannogo sostoyaniya gornykh porod na fil'tratsionnyy protsess i debit skvazhin (Influence of the stress-strain state of rocks on the filtration process and well flow rate): thesis of doctor of technical science, Moscow, 2010.

11. Anikeev D.P., Indrupskiy I.M., Zakiryanov R.A., Ibragimov I.I., Otsenka vliyaniya izmeneniya pronitsaemosti ot davleniya na neodnorodnost' drenirovaniya karbonatnogo kollektora (Assessment of the effect of pressure-dependent permeability changes on the heterogeneity of drainage of a carbonate reservoir), Proceedings of VI International Scientific and Practical Conference “Dostizheniya, problemy i perspektivy razvitiya neftegazovoy otrasli” (Achievements, problems and prospects for the development of the oil and gas industry), 16–18 October 2019, Al'met'evsk: Publ. of ASPI, 2019, pp. 33–36.

12. Indrupskiy I.M., Ibragimov I.I., Zakiryanov R.A. et al., Permeability alteration of carbonate reservoir rock under cyclic geomechanical treatment, IOP Conference Series: Materials Science and Engineering, 2020, V. 921, https://doi.org/10.1088/1757-899X/921/1/012009

13. Sylte J.E., Thomas L.K., Rhett D.W. et al., Water induced compaction in the Ekofisk field, SPE-56426-MS, 1999.

14. Ibragimov I.I., Indrupskiy I.M., Lutfullin A.A., Otsenka effekta geomekhanicheskogo vozdeystviya s pomoshch'yu gidrodinamicheskogo modelirovaniya (Assessment of the effect of geomechanical impact using hydrodynamic modeling), Proceedings of V International Scientific and Practical Conference "Dostizheniya, problemy i perspektivy razvitiya neftegazovoy otrasli" (Achievements, problems and prospects for the development of the oil and gas industry), 12 November 2020, Almet'evsk: Publ. of ASPI, 2020.

Composite rods made of fiberglass are a promising way to increase the efficiency of well operation by rod installations, which are characterized by significantly lower weight, higher strength and corrosion resistance compared to steel rods. Due to the difference in the physical properties of the material of steel and fiberglass pumping rods, the calculation of the optimal operating mode of rod installations requires individual design of the process mode parameters for each specific well.

Experimental field tests were performed to optimize the technological mode of rod installations with a combined fiberglass rod column on the basis of multivariate calculations based on the developed mathematical model of a rod installation with a combined fiberglass rod column. Verification of the developed method for calculating the parameters of the technological mode based on the mathematical model of the rod installation showed a good agreement between the calculated and actual indicators. Based on the results of the field tests, additional liquid and oil production was obtained from the tested wells by increasing the depth of the pump descent and pumping speed. It is shown that the increase in the depth of the pump descent when optimizing the mode is mainly carried out by increasing the length of the fiberglass stage, so there is no significant increase in the load on the rod column. Due to the increased extensibility of fiberglass rods, which cause loss of plunger stroke, wells are optimized to switch to a smaller pump plunger diameter, which simultaneously reduces the maximum load on the rods and the drive. The results obtained are recommended to be taken into account when designing the technological mode of rod installations equipped with fiberglass rods.

References

1. Takacs G., Sucker-rod pumping handbook, Elsevier Science Publ., 2015, 598 p.

2. Timashev E.O., Khalfin R.S., Volkov M.G., Statistical analysis of the failure times and feed rates of downhole pumping equipment in operating parameter ranges (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 2, pp. 96–100.

3. Bakhtizin R.N., Rizvanov R.R., Urazakov K.R., Khakimov T.A., Nasosnye shtangi (Sucker Rods), Ufa: Neftegazovoe delo Publ., 2012, 80 p.

4. Alievskiy P.A., Arutyunov I.A., Bikchentaev R.M. et al., Pumping rods from fiberglass plastic (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2003, no. 12, pp. 62–66. 

5. Zuo Y., Wu X., A comparative study of four rod load reduction techniques for deep-rod pumping, Journal of Petroleum Exploration and Production Technology, 2018, no. 8, pp. 475–483.

6. Ruidong Zhao, Yi Peng, Qiming Li et al., Deep well lifting new solution in Tarim oilfield, SPE-192494-MS, 2018. 

7. Ruidong Zhao, Xishun Zhang, Zhen Tao et al., The research and application of carbon fiber rods in deep oil wells of Xinjiang oilfield, China, SPE-184203-MS, 2016.

8. Gibbs S.G., Application of fiberglass sucker rods, SPE-20151-PA, 1991, https://doi.org/10.2118/20151-PA

9. Cen Xueqi, Wu Xiaodong, Gaofei et al., Optimization of fiber glass and steel composite rod design, Oil Field Equipment, 2012, V. 41(5), pp. 31–35.

10. Bakhtizin R.N., Urazakov K.R., Ismagilov S.F. et al., Dynamic model of a rod pump installation for inclined wells, Socar Proceedings, 2017, no. 4, pp. 74–82.

11. Bakhtizin R.N., Urazakov K.R., Timashev E.O., Belov A.E., A new approach of quantifying the technical condition of rod units with the solution of inverse dynamic problems by multidimensional optimization methods (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 7, pp. 118–122, DOI: 10.24887/0028-2448-2019-7-118-122

12. Urazakov K.R., Timashev E.O., Tugunov P.M., Davletshin F.F., Study on efficiency of rod unit with combined fiberglass rod string (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 7, pp. 123-127, DOI: 10.24887/0028-2448-2019-7-123–127.

One of the promising directions for further improvement and improvement of the operational efficiency of submersible installations of electric-driven pumps (ESP) for oil production is to increase the rotation frequency of the rotor of the installation. When increasing the pump speed the pressure per pump stage increases, the number of pump stage is significantly reduced as well as the length of the installation. This allows to assemble the unit in the shop and assemble it on the well, reduces costs and increases the reliability of installation operations. The performance of a shorter installation is less dependent on the curvature of the well. In an expert opinion, high speed positively effects on the process of reservoir fluid dispersion and gas separation. One of the reasons for the low distribution of high-speed ESP is their lower resource compared to traditional equipment. The lack of reliable failure statistics, the low level of knowledge of wear and dynamics at high speed, and the lack of appropriate test benches create additional methodological difficulties. For high-speed ESP, more stringent requirements are set for the gaps of mobile interfaces to ensure high values of the pump stage head and low rotor dynamics. Therefore, the materials must have high wear resistance. 

The purpose of this work was to study the wear processes of mobile interfaces, the flow part of the pump stage in water with an abrasive when the speed changes. The pump stage 5–50 was tested. It was found that when rotation speed increased from 2950 to 5705 rpm, the wear rate of the radial interfaces increased by 5.8 times, and the wear rate of the axial interfaces increased by 2.5 times. The wear rate of hard alloy bearings depends linearly on the speed and flow rate. The imbalance of the impeller has little effect on the wear of the radial interfaces. The wear rate of the flow part of the impellers increased by 2.6 times, the wear rate of the flow part of the guide device – by 11 times. A test bench with a rotation speed of up to 12000 rpm has been developed for testing high-speed pump stages. When testing a high-speed pump stage with a rotation speed of 9500 rpm, low values of the wear rate of mobile interfaces made of hard alloy were obtained. The dependence of the wear rate of pump stage materials in a corrosive environment on the content of alloying elements is obtained.

References

1. URL: https://www.lepse.com/products/159/

2. Smirnov N.I., Grigoryan E.E., Study of the impact of wear of movable interfaces on failures of an immersible electrically operated vane pump for oil extraction (In Russ.), Problemy mashinostroeniya i nadezhnosti mashin = Journal of Machinery Manufacture and Reliability, 2019, no. 1, pp. 92–97.

3. Litvinenko K.V., Zdol'nik S.E., Mikhaylov V.G., An approach to ESP characteristics degradation modeling under high erosive wear conditions (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 12, pp. 132–135.

4. Ostrovskiy V.G., Upravlenie vtorichnymi techeniyami v stupenyakh neftyanykh nasosov dlya snizheniya ikh gidroabrazivnogo iznosa (Control of secondary flows in the stages of oil pumps to reduce their hydroabrasive wear): thesis of candidate of technical science, Perm', 2013. 

5. Patent RU 2444719 C2, Method of testing materials for hydroabrasive and corrosion wear, Inventors: Smirnov N.I., Smirnov N.N.

6. Smirnov N.I., Yagovkina A.N., Prozhega M.V., Smirnov N.N., Development of methods for materials erosion tests (In Russ.), Mashinostroenie i inzhenernoe obrazovanie, 2017, no. 2(51), pp. 60–68

The article describes the criteria for the introduction of gas-stabilizing devices in the wells of high-temperature layers of the Krasnoleninsky arch deposits. A method for calculating the gas content at the pump intake is presented. The current structure of the production fund of wells is determined by the presence of gas content at the receiving pump of the pre-Jurassic layers of the Krasnoleninsky arch deposits, according to the above method. 54% of the production fund of wells with ESP is operated with gas pumping at the pump reception of more than 50%. The dynamics of changes in gas retention at wells launched after geological and technical measures during the year are described. The choice of gas-stabilizing devices for the operation of wells in pre-Jurassic formations with ESP should be carried out depending on the accompanying complicating factors. Taking into account the complicating factors in the operation of wells in the pre-Jurassic reservoir of the Krasnoleninsky arch deposits, the complete set of additional equipment for the electric center pump is determined. Based on the Oddo – Thomson method adapted to the conditions of high-temperature reservoirs developed and implemented in the production of salt hazard criteria. Salt hazard criteria include three groups that describe the location of the salt formation process during the operation of ESP installations. For salt hazard categories, the criteria for the introduction of additional equipment in the operation of electric center-mounted pumps are defined. Targeted use of expensive additional equipment allowed to increase the efficiency of its use. The effectiveness of the introduction of additional equipment has affected the growth of the development of the complicated fund of wells in the pre-Jurassic formations.

References

1. Gareev A.A., Tsentrobezhnye nasosy v dobyche nefti (problemy i resheniya) (Centrifugal pumps in oil production (problems and solutions)), Ufa: Neftegazovoe delo Publ., 2020, 244 p.

2. Makeev A.A., Shchelokov D.V., Shay E.L., Chirkov M.V., Efficiency of electric centrifugal pumps application for oil production from wells of pre-Jurassic formations (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 8, pp. 74–76, DOI: 10.24887/0028-2448-2020-8-74-76

3. Makeev A.A., Shchelokov D. V., Shay E.L., Complications during the operation of wells of high-temperature deposits in the Oktyabrsky region (Krasnolensky arch) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 2, pp. 42–44, DOI: 10.24887/0028-2448-2020-2-42-44.

4. Oddo J.E., Tomson M.B., Method predicts well bore scale, corrosion, Oil and Gas Journal, 1998, June, pp. 107–114.

Due to the transition of a large number of Russian hydrocarbon fields to the late stages of development, oil reserves produced in such fields are considered hard-to-recover. To extract such reserves, complex multi-interval profiles are designed, the wiring of which must be controlled directly during the drilling. This issue is solved using telemetric wellbore monitoring systems, which are also being developed in Russia. Such the drilling technique requires a high-speed data exchange between the wellhead and the bottom of a well. The data must go to the ground equipment and to the dispatcher in real time. In most cases a hydraulic data link is used for data transmission which has a number of speed and volume restrictions. Companies developing telemetry equipment and its software are trying to increase the speed and volume of data transfer between the wellhead and the bottom by using new sensors, transmitters, encryption and decryption systems, as well as other related equipment. In this case, it becomes necessary to adjust and refine the results obtained. To carry out such studies at the design and debugging stage, before running into the well, the test bench is being developed in the Perm National Research Polytechnic University to imitate a hydraulic data link during well construction. 

Simulation of the hydraulic data link is as follows: the data link medium is emulated through the hydraulic channel by generating rectangular pulses of standard amplitude of a certain frequency. The parameters of the pulses are then changed in such a way as the real transmission medium - a well with drilling fluid (operation of a bit, pumps, column rotation etc.) - before they are fixed by the pressure sensor of the receiving device. The developed test bench is portable and can be used both in laboratory conditions and directly in the production of telemetry systems for testing them before shipment to the customer. Simulate a hydraulic data link during well construction at the stage of development and configuration of telemetry equipment will allow developing a complex signal recognition and decoding algorithm for more accurate transmission of information from the downhole telemetry system to the wellhead. That, in turn, will increase the quality of the incoming information and, consequently, the accuracy of the posting on a complex profile.

References

1. Barton S.P., Teasdale P., Robson R.I. et al., Ultra slim rotary steerable system achieves world record performance in the Middle East, SPE 125678-MS, 2009, DOI: 10.2118/125678-MS.

2. Kuz'mina T.A., Mironov A.D., Experience in the development of objects unproductive using technology multihole drilling (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2012, no. 3, pp. 89–93.

3. Baker Hughes INTEQ’s Guide to measurement while drilling, USA, Houston: Baker Hughes, 1997, 50 p.

4. Neff J.M., Camwell P.L., Field-test results of an acoustic MWD system, IADC/SPE Drilling Conference, Amsterdam, 20-22 February 2007.

5. lmeida Jr. De et al., A review of telemetry data transmission in unconventional petroleum environments focused on information density and reliability, Journal of Software Engineering and Applications, 2015, V. 8, pp. 455–462.

6. Pan'kov I.L., Morozov I.A., Study of the friction coefficient influence on salt rocks mechanical indicators in sample compression of varying heights (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Bulletin of Perm National Research Polytechnic University. Geology. Oil & Gas Engineering & Mining, 2013, no. 7, pp. 57–67.

7. Ust'kachkintsev E.N., Increase productivity of construction in sidetrack of Verkhnekamsk potassium-magnesium salts field (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2012, no. 5, pp. 39–46.

8. Kychkin A.V., Volodin V.D., Sharonov A.A. et al., The synthesis of the hardware and software system structure for remote monitoring and control of the wellbore trajectory while drilling by rotary steerable system (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 11, pp. 128–132.

9. Krivoshchekov S.N., Melekhin A.A., Turbakov M.S. et al., Development of a telemetric system for monitoring downhole parameters in the course of wells construction (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 9, pp. 86–88, DOI: 10.24887/0028-2448-2017-9-86-88.

Digital modernization of oil and gas production is a powerful tool for increasing the efficiency of field development and an innovative driver for the development of the oil and gas industry. Leading oil and gas companies in Russia are transitioning to digital technologies for drilling and production based on the use of machine learning methods and neural network models. An oil and gas well is the main technological object and structure that determines the efficiency of hydrocarbon production at all stages of the field life cycle. The objects of research were complications and emergencies during the construction of oil and gas wells. The purpose of the work is to increase the efficiency of the construction process of oil and gas wells based on the creation of a high-performance automated system for preventing complications and emergencies. This article briefly describes the created automated system for preventing emergency situations during well construction using artificial intelligence technologies. The structure of the automated system and the composition of the main software components are given. The efficiency of the automated system is based on providing the calculation model with a mechanism for a continuous system of transmission, collection, distribution, storage and validation of large volumes of geological and geophysical data (Big GeoData) with elements of blockchain technology. The main advantage of using neural network modeling to solve problems of identifying and predicting complications during the construction of oil and gas wells is to reveal hidden patterns between geological and geophysical, technical and technological parameters. The system has the ability to scale and integrate into any existing oil and gas control and monitoring systems.

Referencies

1. Dmitrievskiy A.N., Eremin N.A., Safarova E.A. et al., Qualitative analysis of time series geodata to prevent complications and emergencies during drilling of oil and gas wells (In Russ.), Nauchnye trudy NIPI Neftegaz GNKAR = SOCAR Proceedings, 2020, no. 3, pp. 31–37, doi: 10.5510/ogp20200300442

2. Kaznacheev P.F., Samoylova R.V., Kurchiski N.V., Application of artificial intelligence methods to improve efficiency in the oil and gas and other raw materials industries (In Russ.), Ekonomicheskaya politika = Economic policy, 2016, V. 11, no. 5, pp. 188–197.

3. Dmitrievskiy A.N., Sboev A.G., Eremin N.A. et al., On increasing the productive time of drilling oil and gas wells using machine learning methods (In Russ.), Georesursy = Georesources, 2020, V. 22, no. 4, pp. 79–85, DOI: https://doi.org/10.18599/grs.2020.4.79-85.

4. Chernikov A.D., Eremin N.A., Stolyarov V.E. et al., Application of artificial intelligence methods for identifying and predicting complications in the construction of oil and gas wells: Problems and solutions (In Russ.), Georesursy = Georesources, 2020, V. 22, no. 3, pp. 87–96, DOI: https://doi.org/10.18599/grs.2020.3.87-96

5. D'yakonov A.G., Golovina A.M., Vyyavlenie anomaliy v rabote mekhanizmov metodami mashinnogo obucheniya (Anomaly detection in mechanisms using machine learning), Proceedings of XIX International conference “Analitika i upravlenie dannymi v oblastyakh s intensivnym ispol'zovaniem dannykh” (Data Analytics and Management in Data Intensive Domains (DAMDID)), Moscow, 10–13th of October 2017, pp. 469–476.

6. Liu F.T., Tony T.K.M., Zhou Z.H., Isolation forest, Proceedings of the 2008 Eighth IEEE Int. Conf. on Data Mining, 2008, pp. 413–422.

7. Gurina E. et al., Application of machine learning to accidents detection at directional drilling, Journal of Petroleum Science and Engineering, 2020, V. 184, DOI:10.1016/j.petrol.2019.106519.

8. Chen T., Guestrin C., Xgboost: A scalable tree boosting system, Proceedings of the 22nd ASM SIGKDD international conference on knowledge discovery and data mining, ACM, 2016, pp. 785–794.

9. Kodirov Sh.Sh., Shestakov A.L., Development of artificial neural network for predicting drill pipe sticking (In Russ.), Vestnik Yuzhno-Ural'skogo gosudarstvennogo universiteta. Seriya. Komp'yuternye tekhnologii, upravlenie, radioelektronika, 2019, V. 19, no. 3, pp. 20-32.

10. Utility model patent application no. 2020129673/03 (053361), Avtomatizirovannaya sistema vyyavleniya i prognozirovaniya oslozhneniy v protsesse stroitel'stva neftyanykh i gazovykh skvazhin (Automated system for identifying and predicting complications during the construction of oil and gas wells), Inventors: Dmitrievskiy A.N., Eremin N.A., Chashchina-Semenova O.K., Fitsner L.K., Chernikov A.D.

11. Utility model patent application no. 2020129671/03 (053358), Avtomatizirovannaya sistema vyyavleniya i prognozirovaniya oslozhneniy v protsesse stroitel'stva neftyanykh i gazovykh skvazhin (Automated system for identifying and predicting complications during the construction of oil and gas wells), Inventors: Dmitrievskiy A.N., Eremin N.A., Chashchina-Semenova O.K., Fitsner L.K., Chernikov A.D.

12. Borozdin S.O., Dmitrievskiy A.N., Eremin N.A. et al., Drilling problems forecast system based on neural network (In Russ.), SPE-202546-RU, 2020, doi:10.2118/202546-RU

13. Arkhipov A.I., Dmitrievskiy A.N., Eremin N.A. et al., Data quality analysis of the station of geological and technological researches in recognizing losses and kicks to improve the prediction accuracy of neural network algorithms (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 8, pp. 63–67, DOI: 10.24887/0028-2448-2020-8-63-67

14. Noshi C.I., Schubert J.J., The role of machine learning in drilling operations. A review, SPE-191823-18ERM-MS, 2018, DOI:10.2118/191823-18ERM-MS.

15. Kanfar R. et al., Real-time well log prediction from drilling data using deep learning, arXiv preprint arXiv:2001.10156, 2020.

16. Yuanjun Li et al., Deep learning for well data history analysis, SPE-196011-MS, 2019, https://doi.org/10.2118/196011-MS

The paper cover the lab and pilot tests results on reduction of sulfate-reducing bacteria activity in produced water of oil gathering, transportation and treatment systems at Vietsovpetro offshore facilities. Based on field tests results, developed the requirements to biocides, recommended for application on the offshore oil producing facilities. It is recommended to select biocides and conditions for its application at the certain oil field, based on lab and pilot tests results following further gathering of associated water samples and its analysis on sulphate-reducing bacteria and hydrogen sulphide content. While performing the biocides pilot testing, the emphasis should be made towards not only the effective suppression of sulphate-reducing bacteria activity, but also the physical-chemical interaction with other field chemicals in order to avoid negative effect on technological processes of oil treatment. Confirmed, that the planktonic sulphate-reducing bacteria almost immediately suppressed by minimal concentrations of biocides (120–150 ppm), but rapidly recover due to the product infected by sulphate-reducing bacteria, which received from other offshore fixed platforms. To suppress sedentary (filmy) types of sulphate-reducing bacteria the higher biocide concentrations (above 500 ppm) is required. Suppression of sulphate-reducing bacteria at process platforms of oil treatment led to the reduction of dissolved hydrogen sulphide by 3–4 times in produced water. It is recommended to apply quick tests for identifying the infection grade by the sulphate-reducing bacteria and the efficiency of biocides in field conditions only for preliminary assessment, while the final evaluation on sulphate-reducing bacteria content should be performed by the standard API RP 38 method with the identification of the sulphate-reducing bacteria forms (sedentary/planktonic).

References

1. Sanders P.F., Monitoring and control of sessile microbes: cost effective ways to reduce microbial corrosion, In: Microbial Corrosion-1: edited by Sequeira C.A.C., Tiller A.K., Elsevier Applied Science, New York, 1988, pp. 191–223.

2. Zaytseva O.V., Klenova N.A., Microbiologically influenced corrosion of oilfields' pipelines and steel alloying as a way of fighting it (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2008, no. 4, pp. 92–95.

In the context of periodic changes in legislative requirements in the field of rational use of hydrocarbon resources, as well as tightening of norms and restrictions on emissions of pollutants into the atmosphere, increasing fines and payments, Zarubezhneft JSC is faced with an acute problem of urgent liquidation of systems for flaring and dispersing associated petroleum gas, and also with the need to design and implement effective ways to use it. With the correct choice of the option to increase the level of useful APG utilization and timely monitoring of the process of its implementation, investment in such projects is not only a method of fulfilling legislative norms in terms of the effective use of 95% of produced gas, but also an economically justified procedure for making a profit. The article describes existing design solutions for the preparation of associated petroleum gas from the Kharyaga field. The adsorption properties of foreign and domestic molecular sieves were investigated under conditions of an abnormally high content of hydrogen sulfide in the feed stream. The idea of increasing the profitability of the Gas Program facilities by carrying out a comprehensive gas treatment in one stage is presented. The main goals and objectives of the project are: decrease in costs in the preparation of associated petroleum gas; selection of the optimal option for gas desulfurization; replication of technology at similar facilities.

The use of the new adsorption system made it possible to increase the profitability of gas desulfurization and achieve 99.9% of gas purification from harmful impurities in one stage. The results of the pilot operation of the molecular sieve gas treatment unit showed the prospects and the possibility of replicating this technology in the oil industry.

References

1. Bekirov T.M., Promyslovaya i zavodskaya obrabotka prirodnykh i neftyanykh gazov (Field and plant processing of natural and petroleum gases), Moscow: Nedra Publ., 1980, 283 p.

2. Murin V.I. et al., Tekhnologiya pererabotki prirodnogo gaza i kondensata (Natural gas and condensate processing technology), Part 1, Moscow: Nedra-Biznestsentr Publ., 2002, 517 p.

3. Kel'tsev N.V., Osnovy adsorbtsionnoy tekhniki (Basics of adsorption technology), Moscow: Khimiya Publ., 1976, 512 p.

The article examines the effect of the quantitative content of resins, asphaltenes and paraffin in oil on the pour point of oil. The effect of a depressant additive on the pour point of oil and the transition of its state from Newtonian to non-Newtonian is also shown. The process of paraffin crystals precipitation into the solution with a decrease in oil temperature and its transition from a Newtonian state to a non-Newtonian one is considered. It is noted that at a certain temperature, Newtonian oil turns into a colloidal solution and begins to acquire the properties of a non-Newtonian fluid. With a further decrease in temperature, the viscosity of the oil will increase, and the area of hysteresis loop between the shear rate and the magnitude of the shear stress increases. The effect of resins and asphaltenes on the process of oil cooling is considered. It is noted that neutral resins form true solutions with oil products, asphaltenes form suspensions and colloidal solutions. On the basis of a large number of previous experiments, it was found that the quantitative ratio of the mass of paraffin to the amount of resins and asphaltenes does not unambiguously determine the pour point of oil. It is shown that an increase in the pour point of oil with an increase in the paraffin content in it can be disturbed due to the qualitative ratio of resins, asphaltenes and paraffins, which leads to a depressant effect. The relationship between the pour point of oil and the critical transition temperature from Newtonian to non-Newtonian is also considered. The effectiveness of the depressant effect is manifested from the moment the oil transitions to the non-Newtonian state. It is assumed that under the influence of a depressant additive, the pour point and the critical temperature of the transition from Newtonian to non-Newtonian change by the same value. This assumption is based on experimental data obtained by various authors. The relevance of the results obtained is that technologically the temperature of the beginning of paraffin precipitation is more important than the pour point of oil. This is due to the fact that during the transition of oil to a non-Newtonian state, dynamic viscosity and static shear stress increase. Operation of the pipeline in the area of the non-Newtonian state of the liquid is impractical due to increasing losses and the threat of oil solidification when pumping is stopped.

References

1. Rakov P.P., Khananyan M.M., Bor'ba s otlozheniyami parafina na neftepromyslakh (Control of paraffin deposits in oil fields), Moscow: Publ. of  Gosinti, 1958, 95 p.

2. Mazepa B.A., Parafinizatsiya neftesbornykh sistem i promyslovogo oborudovaniya (Waxing of oil collection systems and fishing equipment), Moscow: Nedra Publ., 1966, 175 p.

3. Gubin V.E., Gubin V.V., Truboprovodnyy transport nefti i nefteproduktov (Pipeline transport of oil and oil products), Moscow: Nedra Publ., 1982, 296 p.

4. Il'in A.N., Polishchuk Yu.M., Yashchenko I.G., High-paraffinic oils: patterns of spatial and temporal changes in their properties (In Russ.), Neftegazovoe delo, 2007, no. 2, URL: http://ogbus.ru/files/ogbus/authors/Iliin/Iliin_1.pdf 

5. Ashmyan K.D., Nikitina I.N., Nosova E.N., Factors influencing the loss of oil asphaltene, resin and paraffin substances (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 11, pp. 126–128.

6. Angizhitov A.Sh., Reologicheskie svoystva neftesmesey, perekachivaemykh po nefteprovodam Kazakhstana (Rheological properties of oil mixtures pumped through Kazakhstan oil pipelines), Proceedings of International scientific-practical conference, Atyrau, 2015.

7. Shadrina P.N., Sovershenstvovanie tekhnologiy bor'by s asfal'tosmoloparafinovymi otlozheniyami na neftepromyslovom oborudovanii mestorozhdeniy vysokovyazkikh neftey (Improving technologies for combating asphalt-resin-paraffin deposits on oilfield equipment of high-viscosity oil fields): thesis of candidate of technical science, Ufa, 2017.

8. Bazhaykin S.G., Dorozhkin V.Yu., Yusupov O.M., Gulina N.N., Issledovanie effektivnosti perekachki vysokoparafinistoy smesi neftey po nefteprovodu GNPS “Kumkol'” – GNS “im. B. Dzhumagalieva” – GNPS “Shymkent” (Study of the efficiency of pumping a high-paraffin mixture of oils through the pipeline HOPS "Kumkol" - HOPS "them. B. Dzhumagalieva" - HOPS" Shymkent"), / // Proceedings of International scientific-practical conference, Atyrau, 2015.

9. Tronov V.P., O mekhanizme parafinizatsii promyslovogo oborudovaniya (On the mechanism of paraffinization of fishing equipment), Collected papers “Bor'ba s otlozheniyami parafina” (Fighting paraffin deposits), Moscow: Nedra Publ., 1965, 339 p.

10. Chertkov Ya.B., Neuglevodorodnye soedineniya v nefteproduktakh (Non-hydrocarbon compounds in petroleum products), Moscow: Khimiya Publ., 1964, 226 p. 

11. Didenko V.S., Nikolaev A.V., Study of asphaltene-resin-paraffin deposits inhibitors and their effect on oil flow characteristics based on new methodic approach (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 1, pp. 106–109.

12. Sunagatullin R.Z., Nesyn G.V., Khasbiullin I.I., Measurement techniques of wax appearance temperature in crude oil and diesel fuel (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2018, no. 1, pp. 21–29.

13. Lyapin A.Yu., Nekuchaev V.O., Ovchinnikov S.K., Mikheev M.M., Investigation of the reasons for decreased efficiency of depressant additives during the pumping of paraffinic oils (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2020, V. 10, no. 2, pp. 157–163.

The paper discusses the issues and peculiarities of wax deposition in non-isothermal main pipelines for ‘hot’ pumping of oil, characterized by an increased content of paraffins - positive fluid loss temperatures, risks of congelation and intensification of wax deposition. Problems of pumping waxy oils are solved by thermochemical methods aimed at eliminating the risks of blocking the section at low ambient temperatures and long downtime of the linear part for the period of regular scheduled and emergency repair work. If the issue of determining the permissible safe shutdown time and start-up modes has been given a fairly large number of scientific works both in domestic and foreign literature, then the tasks of optimizing the operating costs associated with determining the required frequency of pigging, dosages of chemical reagents, today, remain unresolved and require rational solutions that are necessary and sufficient in order to maintain energy efficiency and system reliability. At the same time, the issues of ecology, especially for Arctic oil and gas regions, dictate new more stringent requirements for the special pumping methods, developed decades ago. 

This article presents the results of the performed analysis of the influence of various factors on the efficiency of hot oil pumping, substantiates the shortcomings of the equipment and chemical reagents used, caused by an insufficient level of preheating of oil due to a number of technological limitations adopted decades ago. The results of experimental studies of the dependence of the intensity of wax deposition on the temperature gradient in the near-wall zone are presented, confirming the advantages of low-temperature pipeline transportation of preliminarily heat-treated oil in comparison with a preheating scheme characterized by shock dosages of chemical reagents, on the one hand, partially solving the problem of extending the permissible safe shutdown time, and with the other, leading to the intensification of wax depositions on the inner surface of the walls of a non-insulated oil pipeline.

References

1. Tugunov P.I. et al., Tipovye raschety pri proektirovanii i ekspluatatsiy neftebaz i nefteprovodov (Typical calculations in the design and operation of tank farms and oil pipelines), Ufa: Dizain-PoligrafServis Publ., 2002, 658 p.

2. Karimov R.M., Mastobaev B.N., Change of technology of swapping of oil on the oil pipeline "Uzen-Atyrau-Samara" with development of petrotransport system of the western Kazakhstan (In Russ.), Transport i khranenie nefteproduktov i uglevodorodnogo syr'ya, 2010, no. 2, pp. 9–14.

3. Karimov R.M., Mastobaev B.N., Rheologikal features of the West Kazakhstan oil blend (In Russ.), Transport i khranenine nefteproduktov i uglevodorodnogo sur’ya, 2011, no. 2, pp. 3–7.

4. Karimov R.M., Mastobaev B.N., Joint transportation of high-viscosity and highly solidifying oils from Western Kazakhstan via the Uzen-Atyrau-Samara oil pipeline (In Russ.), Transport i khranenie nefteproduktov i uglevodorodnogo syr'ya, 2012, no. 1, pp. 3–6.

5. Karimov R.M., Bakhtizin R.N., Mastobaev B.N., The effect of high-molecular components on flow properties, depending on the structural-group and fractional oil content (In Russ.), Socar Proceedings, 2016, no. 1, pp. 42-50. 

6. Sunagatullin R.Z., Karimov R.M., Mastobaev B.N., Vliyanie temperaturnogo gradienta na granitse razdela “potok-stenka” na intensivnost' parafinootlozheniy (Influence of the temperature gradient at the “flow-wall” interface on the intensity of paraffin deposition), Proceedings of XIV International educational, scientific and practical conference "Pipeline transport - 2019", Ufa: Publ. of USPTU, 2019, pp. 132–133.

7. Revel'-Muroz P.A., Bakhtizin R.N., Karimov R.M., Mastobaev B.N., Joint usage of thermal and chemical stimulation technique for transportation of high viscosity and congealing oils (In Russ.), Socar Proceedings (Nauchnye trudy), 2017, no. 2, pp. 49–55.

8. Revel'-Muroz P.A., Bakhtizin R.N., Karimov R.M., Mastobaev B.N., Joint transportation of heavy and wax oil blended (In Russ.), Socar Proceedings, 2018, no. 2, pp. 65–70.

9. Armenskiy E.A., Novoselov V.F., Tugunov P.I., Study of thermal phenomena and dynamics of wax deposition in oil pipelines (In Russ.), Neft' i gaz, 1969, no. 10, pp. 77–80.

10. Tronov V.P., Teoreticheskaya otsenka vliyaniya fizicheskikh svoystv poverkhnostey kachestva obrabotki i drugikh faktorov na intensivnost' otlozheniy parafina (Theoretical assessment of the influence of the physical properties of surfaces, processing quality and other factors on the intensity of wax deposits), Proceedings of TatNIPI, 1962, V. 4, pp. 400–412.

11. Denisov E.F., Karimov R.M., Makarenko O.A., K voprosu o primenenii khimicheskikh reagentov dlya ochistki ot asfal'to-smoloparafinovykh otlozheniy (On the question of the use of chemicals for cleaning from asphalt-resin-paraffin deposits), Proceedings of International scientific and technical conference dedicated to the memory of academician A.Kh. Mirzajanzade, Ufa: Publ. of USPTU, 2016, 314 p.

12. Karimov R.M., Zaplatin A.V., Tashbulatov R.R., The use of twisted heat exchangers from coils of small bend radius for heating and heat treatment of oil (In Russ.), Delovoy zhurnal Neftegaz.ru, 2018, no. 12, pp. 45–49.

13. URL: https://asgard-service.com /works/ochistka-teploobmennikov-nps-chikshino 

14. URL: https://asgard-service.com/works/ochistka-mezhtrubnogo-prostranstva-teploobmennika-t-506-kozhuhotrub....

15. URL: https://asgard-service.com/works/ochistka-teploobmennikov-podogreva-nefti-na-knpz.

16. Karimov R.M., Tashbulatov R.R., Zaplatin A.V., Coiled heat exchanger with small radius bent tubes for controlled heat treatment of high viscosity waxy oil, IOP Conf. Series: Earth and Environmental Science, 2019, V. 272, pp. 022193, doi:10.1088/1755-1315/272/2/022193.

The crude oil rheological properties significantly depend on its internal structure, the control of which is a promising area of research. Technologies that use various physical fields (acoustic, vibrational, magnetic, cavitation, etc.) make it possible to control the viscosity-temperature properties of oils and are the most promising due to their efficiency and economy. It is shown that the reversible processes of destruction of the native internal structure of thixotropic oils underlie the phenomenon of ‘memory’, which is advisable to use for technologies for controlling the oil rheological properties by physical and mechanical effects. The paper provides a substantiation of the criterion for the effectiveness of methods of physical and mechanical action on the supramolecular structures of oils, as which it is proposed to use the ratio of the increment of thixotropy energy due to the broken intermolecular bonds of the internal structure to the energy spent on the oil processing. Based on the experimental data of approbation, the efficiency coefficients of five promising exposure to physical and mechanical methods were obtained: plasma-pulse impact exceeds 3000, the rotor-pulsating – 400, cavitation in a hydrodynamic transonic jet-nozzle apparatus – 300, microwave oil treatment and processing by a rotating electromagnetic field is no more than 50. Thus, the most effective was the method of pulse-plasma exposure (the Yutkin method), the indisputable advantages of which include low energy consumption, but also the need for increased safety measures. The rotary-pulsating impact is not inferior in terms of viscosity reduction, but consumes 7 times more energy. A single treatment in a hydrodynamic transonic jet-nozzle apparatus gives a relatively small decrease in viscosity (less than 5%), but on the other hand, it shows a significantly low energy consumption for the processing.

The use of technologies for controlling the rheological characteristics of pumped crude oils in the future allows: to increase the throughput of the oil pipeline; maintain the specified pumping capacity at reduced operating modes during scheduled maintenance; increase the efficiency of pumping units running on heavy oils; to stabilize paraffins in suspended (dissolved) state; to reduce the consumption of depressant, drug reduction agents or wax inhibitors. The combination of various exposure to physical and mechanical methods and chemical reagent treatment of oil opens up wide opportunities for improving the technology of pumping heavy oils.

References

1. Gol'yanov A.I., Grisha B.G. et al., Comparative evaluation of the "hot" batching efficiency (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2018, V. 8, no. 6, pp. 642–649. 

2. Abramzon L.S., Iskhakov R.G., Tugunov P.I., Ratsional'naya perekachka vyazkikh i zastyvayushchikh neftey sovmestno s razbavitelem (Rational pumping of viscous and solidifying oils together with the diluent), Moscow: Publ. of VNIIOENG, 1977, 59 p. 

3. Kutukov S.E., Brot R.A., Determination of shock pressure in a pipeline with gas-saturated oil in transient modes (In Russ.), Neftegazovoe delo, 2005, no. 3, pp. 199–205. 

4. Revel'-Muroz P.A. et al., Estimation of the oil pumping technology effectiveness with drag reduction agents (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 1, pp. 90–95.

5. Gol'yanov A.I. et al., Reduction of flow resistance in pipes by means of anti-turbulent additives. Review and case history (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2012, no. 2 (6), pp. 80–87.

6. Zhuyko P.V., Razrabotka printsipov upravleniya reologicheskimi svoystvami anomal'nykh neftey (Development of management principles for rheological properties of abnormal oils): thesis of doctor of technical science, Ukhta, 2003.

7. Anufriev R.V., Volkova G.I., Yudina N.V., Influence of ultrasonic treatment on structural-mechanical properties of oil and sedimentation (In Russ.), Neftekhimiya = Petroleum Chemistry, 2016, V. 56, no. 5, pp. 454–460.

8. Loskutova Yu.V., Vliyanie magnitnogo polya na reologicheskie svoystva neftey (Influence of the magnetic field on the rheological properties of oils): thesis of candidate of chemical science, Tomsk, 2003. 

9. Syunyaev Z.I., Fiziko-khimicheskaya mekhanika neftey i osnovy intensifikatsii protsessov ikh pererabotki (Physicochemical mechanics of oils and the basics of intensification of their refining processes), Moscow: Publ. of Gubkin Institute, 1979, 39 p.

10. Sharafutdinov Z.Z., The survey of the theory of solutions (In Russ.), Nauka i tekhnologii truboprovodnogo transporta nefti i nefteproduktov, 2017, no. 1(28), pp. 70–81.

11. Unger F.G., Andreeva L.N., Fundamental'nye aspekty khimii nefti. Priroda smol i asfal'tenov (Fundamental aspects of oil chemistry. The nature of the resins and asphaltenes), Novosibirsk: Nauka Publ., 1995, 192 p.

12. Loskutova Yu.V. et al., Raschet energeticheskikh parametrov gidromekhanicheskogo razrusheniya struktury neftey (Calculation of energy parameters of hydromechanical destruction of the structure of oils), Collected papers “Problemy khimii nefti i gaza” (Problems of chemistry of oil and gas), Tomsk: Publ. of IAO SB RAS, 2004, pp. 235–237.

13. Boytsova A.A., Kondrasheva N.K., Rheological properties of hydrocarbon systems with a high content of resins and asphaltenes (In Russ.), IFZh = Journal of Engineering Physics and Thermophysics, 2018, V. 91, no. 4, pp. 1098–1105.

14. Ageev P.G. et al., Experimental study of plasma-impulse impact: intensity of pressure pulsations in the medium processed (In Russ.), Problemy mashinostroeniya i nadezhnosti mashin = Journal of Machinery Manufacture and Reliability, 2019, no. 2, pp. 106–112.

15. Promtov M.A. Stepanov A.Yu., Aleshin A.V., Metody rascheta kharakteristik rotornogo impul'snogo apparata (Methods for calculating the characteristics of a rotary pulse apparatus), Tambov: Publ. of TSTU, 2015, 148 p.

The article deals with the results of research on the use of thermomechanical methods of soil development during drilling for diagnosing the technical condition and repair of pipelines in various climatic condition. The design and technical characteristics of a drilling rig with the use of a gas turbine unit as a source of heat and electric energy are given. The description of the mathematical model of the thermomechanical effect of heat flow on the soil is given. The model is based on classical laws and equations of continuum mechanics. The method of determining the effective stresses in the soil depending on pressure surges and flow surges is given. The analysis of influence of density of a heat flux at heat exchange and mass transfer, on thermodynamic and gasdynamic characteristics of process of influence of a heat flux on a ground is carried out. The results of the studies showed a significant difference between the calculated values of tensile stresses in the soil when the soil is heated from 10 to 200 °C from the values of stresses determined by mathematical models that do not take into account heat transfer and mass transfer. Thus, at phase transitions and mass transfer of moisture (with a change in moisture content from 40 to 10%), the calculated deformation (shrinkage) of the soil from the horizontal surface was 25 %. At the same time, shear stresses increased from 0.3 to 1.5 MPa, which, in the presence of a difference in the moisture content and temperature fields, is comparable to stresses. Experimental – industrial designs and scientific bases for creation of new generation of the thermomechanical drilling tool for well diagnostics and repair of pipelines with application of mobile gas-turbine engine as sources of thermal and electric energy are developed.

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