The pilot-industrial works to introduce new equipment – the GeoSpec NMR spectrometer of modification 2/53 were carried out in Tyumen branch of SurgutNIPIneft in 2016. The results of measurements on samples of different lithologic types of rocks from all areas of work of Surgutneftegas OJSC are considered. The description of the GeoSpec device of modification 2/53 and features of its operation is given.

The use of the NMR spectrometer to determine the effective porosity allowed to accelerate the process of evaluating the effective porosity, to conduct studies on irregularly shaped samples, including boring sludge. The method made it possible to study samples, saturated as by the formation water model, and kerosene. With the correct adjustment of the instrument, the saturating liquid did not affect the accuracy of determining the total and effective porosity.

Analysis of the results of the performed studies has shown the possibility of working with terrigenous, carbonate and volcanogenic rocks. Pre-adjustment of the technique on standard samples is required for each type of rock. The use of standard time cutoffs reduces the accuracy of determining the effective porosity and can only be used for a rough estimate of the effective porosity in the intervals of the broken core recovery. This approach can also be implemented to interpret the results of the sludge investigation when core sampling is not performed. Preliminary setting of the time cutoffs at comparing the results with the data obtained using the standard method for determining the effective porosity, increase the accuracy of the effective porosity estimation.

The results of the use of the NMR spectrometer to evaluate the effective porosity indicate a high reliability of the method and an extended field of application in comparison with the standard procedure.

References

1. Coates C., Xiao Lizhi, Prammer M.G., NMR logging principles and applications, Houston: Halliburton Energy Services, 1999, 335 p.

2. GeoSpec 2-53: User manual V. 1.8. Oxford instruments magnetic resonance, Abingdon: Industrial Analysis, 2013, 34 p.

The qualitative fastening of the shanks is one of the most urgent problems at sidetracking, especially in the case of high water cut of entering formation, and a necessary condition for long-term and accident-free operation of wells for various purposes. The main factors affecting the fastening quality are considered.

Specialists of the Fedorovsk Department of EOR Methods and Wells Workover are carrying out complex work aimed at improving the technology of sidetracking and minimizing the impact of negative factors on the further operation of the well. Combating overflows is carried out by forecasting and analyzing various data obtained both at the planning stage and during the work on the well. To ensure the reliability of the forecast, at all stages of sidetracking, statistical data are collected on the state of the well and the deviations of the technological process from the planned sidetracking and shank fastening programs. To reduce the number of operators in the analysis of data, the shank fastening quality factor was introduced, which allows with high accuracy to predict the behind-the-casing flow before the well development work. As an example, the behind-the-casing flow is considered in wells No. 1053 and 3230 of the East Surgut field and in wells No. 4289 and 865 of the Sarymo-Russkinskoye field. Taking into account the results obtained analytically, experimental works were carried out to determine the actual pressures at which the cement ring is destroyed.

Analysis of the results of computational studies and practical experiments has shown that it is not possible to exclude the behind-the-casing water flow only by changing the formulation and composition of plug-back mixtures. Prospective directions of works are outlined.

References

1. Novokhatskiy D.F., Nizhnik A.E., Myagkiy Ya.B., Timofeeva E.V., On the contact density of expanding cement stone with casing pipes (In Russ.), Burenie i neft’, 2007, no. 12, pp. 46–48.

Restoring of casing strings integrity during wells workover, is relevant for most fields operated for 15 years and more. Corrosion processes, high injection pressures lead to an increase in the number of cases of loss of production strings tightness. Depending on the operating conditions, a number of negative factors affect to a certain extent the service life of the casing string, the main ones being external and internal corrosion, mechanical wear of the production string during tripping operations.

At present, replacement of the defective part of the production string, located in the free, i.e. uncemented and unstuck casing section, includes a set of works, involving the dismantling and installation of the lifting unit and the working platform, digging the pit and unscrewing of the leaky pipe with the help of machine keys, that significantly complicates the repair of the well.

To facilitate the replacement of the upper part of the production string, a new device UOEK-146 (168) for the unscrewing of the production string, allowing the production  string to be separated precisely at the given joint without the use of machine keys, hydraulic anchor, rotor, drill pipes, was designed and introduced. The device is intended for the unscrewing of the production string in the wells cased with casings 146 and 168 mm in diameter. The operation of the device is based on converting the translational motion of the tubes into rotation using a screw with a large pitch. In this case, the torque is transmitted to the production string through hydraulic anchors. The main components and the operating principle of UOEK-146 (168) are considered.

The device under consideration is applied in six wells in Oil and Gas Production Department Lyantorneft. The results of field trials confirmed the efficiency and reliability of the device.

References

1. Spravochnik mastera po dobyche nefti, gaza i kondensata (Handbook for the farm boss): edited by Batalov D.A., Surgut: Neft' Priob'ya Publ., 2010.

This article deals with the problems of hydraulic fracturing of layers of complex objects, both fr om a constructive point of view (horizontal wells equipped with ‘unmanaged arrangements’ and arrangement for multistage fracturing) and from the point of view of the proximity of water-saturated interlayers. The author analyzed a number of wells operations maintained by standard method and new technology. The main principles of new methodology are formulated, and the variations in the application of existing technologies and their analogs are examined. Many oil companies consider as inexpedient or not promising the solution of this problem by re-fracturing operations using unmanaged arrangements (slotted filter, openhole etc.). We showed the possibility of such solution without increasing the additional costs. Lifetime extension of wells operating in unconventional modes, as objects with high initial and current investments, is extremely unprofitable for oil and gas producing enterprises. To improve the efficiency of fracturing operation on existing and new a revised methodology has been considered. The main principle of this methodology is the use of new technologies and materials to increase the effective fracture area under conditions wh ere standard technologies are not very effective or completely unsuitable. Various types of compositions for flow deflection are considered, both promising for use and used in practice. Studies were carried out on the economic and technological effectiveness of the work. Conclusions are made about the prospects of using the implemented technology and the possibility of its further improvement.

References

1. Economides M. J., Martin T., Modern fracturing enhancing natural gas production, USA, Houston: Energy Tribune Publishing Inc., 2007, 509 p.

Most of the exploitable deposits of Oil and Gas Production Department Bystrinskneft, located in the Surgut region, are at a late stage of development. In this regard, most of the geological and technical activities are related to repair and insulation works. More than 800 well workover operations with the repair and insulation works are carried out annually on the well stock of Surgutneftegas OJSC. At the same time, every fourth well is being repaired by well workover crews of Bystrinskneft. Based on the experience, accumulated by Bystrinskneft, it is shown, that increasing the repair and insulation works efficiency requires an integrated approach. The main factors affecting the quality of work are given. Within the framework of the repair and insulation works development concept, five directions have been singled out. Organizational and technical measures, covering all production and organizational processes, have been developed. Organizational measures include professional development of specialists and provision of effective repair planning. Criteria are established for the necessity of repair and insulation works carrying out taking into account the technical state of the well, the economic feasibility and the terms of the license agreement. To optimize and simplify the choice of technologies and materials, selection algorithms have been developed for the cases of the need to eliminate the leaks in the production string and cross flows behind the casing. The main technological measures are considered    

At present, scientific and technical innovations are one of the main factors that determine the economic growth and successful development of Surgutneftegas OJSC. Widely exploited in many spheres of activity of oil companies, laser devices can significantly improve the efficiency of technical systems. Volumes of the use of laser technique at the modernization of equipment and technology in Surgutneftegas OJSC are increasing every year, in particular, in the marking of equipment, in the hardening of the threaded surface of drill pipes, high-precision welding et al.

At the end of 2015, the next step in the development of the use of laser technology was the manufacture and installation of laser devices for measuring the length of pipes in existing technological lines for the repair of tubing of the Oil and Gas Production Department Fedorovskneft. The devices are designed to exclude the influence of mechanical factors on the accuracy of the measurement in order to improve the system of preparation and repair of tubing.

The device is a complex of three components: a manipulator, a support and a drop-jet marker. The manipulator provides one degree of freedom: vertical movement on the rack, on the bracket of which the laser range finder is installed. The support is designed to stop the pipe strictly at a certain point at a fixed distance from the laser source of optical radiation, which is provided by a system of inductive and optical sensors.

Analysis of the results of pilot testing of laser devices has shown that applying a measured value of length to the pipe surface allows to optimize the measurement of the total length of the tubing suspension during tripping operations. After the successful testing of laser devices for measuring the length of the pipes of Surgutneftegas OJSC a decision was made to implement this equipment at all specialized pipe repair bases in the oil and gas production departments of the company.

References

1. Boreysho A.S., Lazery: Ustroystvo i deystvie (Lasers: design and function), St. Petersburg: Publ. of Mechanical Institute, 1992, 215 p.

2. Chicherov L.G., Molchanov G.V., Rabinovich A.M., Raschet i konstruirovanie neftepromyslovogo oborudovaniya (Calculation and design of oilfield equipment), Moscow: Nedra Publ., 1987, 251 p.

Regional criteria have been defined on the basis of world exploration experience analysis to substantiate by reef controlled oil-bearing zones. Presence of deep-water paleobasin with carbonate sedimentation and favorable paleoecology for reef development are main criteria to begin exploration for rich reef hydrocarbon deposits. The postdepositional inversional regional slope is an important criterion to look for large hydrocarbon deposits are controlled by barrier reefs.

Application of the defined criteria to substantiate exploration development around the Orenburg region has resulted in confirmation of earlier forecasted new exploration play had to be controlled by the Upper Devonian reefs. 705 square kilometres of 3D seismic acquisition within the forecasted perspective zone were resulted in mapping of big groop of the Upper Frasnian isolated basinal reefs. Reef highs – 200-250 m, acreages – 0,7-1,7 km2. Due to drilling of successful exploration wells the rich oil-bearing zone has been revealed on reefs: oil deposits were discovered in reef bodies, in the Lower Famenian and Carboniferous layers in the above-reef compaction closures too.

As a result of the regional criteria application new exploration play of Lower Famenian barrier reef has been revealed. The last was first delineated around the south-east of Volga-Ural Province. Together with Zavolzhian barrier reef the Lower Famenian barrier reef formed the Bobrov-Pokrov Swell of the Mukhano-Erokhov Trough’s southern margin in the Orenburg Oblast. Postdepositional inversional regional slope of the trough’s margin has provided a creation of above-reef closures, which are controlled large oil-bearing zone in the Carboniferous, Mid-Famenian and Upper Famenian layers. Oil deposits in the Famenian were placed along the Lower Famenian barrier reef and are the present-day perspective exploration play.

References

1. Dentskevich I.A., Oshchepkov V.A., Regularities in the location of oil deposits in the side zones of the Mukhanovo-Erokhivsky trough (In Russ.), Geologiya nefti i gaza, 1989, no. 5, pp. 21–23.

2. Dentskevich I.A., Khomentovskaya O.A., Vozmozhnosti seysmofatsial'nogo analiza pri poiskakh lovushek nefti v karbonatnom razreze franko-turneyskogo kompleksa (Capabilities of seismic facies analysis in the search for oil traps in the carbonate section of the Franco-Tournaisian complex), Collected papers “Geologiya i razvedka mestorozhdeniy nefti i gaza yugo-vostoka Russkoy plity” (Geology and exploration of oil and gas deposits of the southeast of the Russian plate), Moscow: Publ. of VNIGNI, 1990, pp. 34–39.

3. Kuznetsov V.G., Geologiya rifov i ikh neftegazonosnost' (Geology of reefs and its oil and gas potential), Moscow: Nedra Publ., 1978, 304 p.

4. Mirchink M.F., Mkrtchyan O.M., Khat'yanov F.I. et al., Rify Uralo-Povolzh'ya, ikh rol' v razmeshchenii zalezhey nefti i gaza i metodika poiska (Reefs of the Ural-Volga region, its role in the location of oil and gas deposits and search methods), Moscow: Nedra Publ., 1974, 152 p.

5. Nikitin Yu.I., Ostapenko S.V., Shcheglov V.B., New branch of activities pertaining to geological prospecting in Orenburg region (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2011, no. 11, pp. 13–18.

6. Hriskevich M.E., Middle Devonian reef production, Rainbow area, Alberta, Canada, AAPG Bulletin, 1970, V. 52, no. 12, pp. 2260–2281.

7. Mesolella K.J., Robinson J.D., McCormick L.M., Ormiston A.R., Cyclic Deposition of silurian carbonates and evaporites in Michigan Basin, AAPG Bulletin, 1974, V. 58, no. 1, pp. 34–62.

8. Malek-Aslani M., Lower Wolfcampian reef in Kemnitz field, Lea County, New Mexico, Bulletin of Amer. Assoc. Petrol. Geol., 1970, V. 54, no. 12, pp. 2317–2335.

9. Sams R.H., Gulf Coast stratigraphic traps in the Lower Cretaceous carbonates, Oil and Gas Journal, 1982, V. 80, no. 8, pp. 177–182, 185–188.

10. Wright W.E., Abo reef: prime West Texas target: Part II, Oil and Gas Journal, 1962, V. 60, no. 32, pp. 187–194.

11. Hemphill C.R., Smith R.I., Szabo F., Geology of Beaverhill Lake Reefs, Swan Hills Area, Alberta, In: Geology of Giant Petroleum Fields: edited by Halbouty M.T., AAPG Memoir 14, Tulsa: American Association of Petroleum Geologists, 1970, pp. 50-90.

12. Neuman A.C., Macinture I., Reef response to see level rise: keep-up, catch-up or give-up, Proceedings of Fifth International Coral Reef Congress, Tahiti, 1985, pp. P. 105–110.

13. Nikitin Yu.I., Ostapenko S.V., Interrelationship between oil-bearing capacity of Volga-Uralian Province and plate tectonics of the Urals (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2008, no. 12, pp. 14–17.

14. Vilesov A.P., Boyarshinova M.G., Vinokurova E.E., Znachenie stromatolitov v formirovanii karkasa famenskikh rifov Volgo-Ural'skoy neftegazonosnoy provintsii (Role of stromatolites in Famenian reef framework formation of Volga-Ural oil-and-gas-bearing Province), Collected papers “Geologiya rifov” (Geology of reefs), Proceedings of Vserossiyskogo litologicheskogo soveshchaniya, Syktyvkar: Publ. of Institute of Geology of the Komi Science Center of the Ural Branch of the Russian Academy of Sciences, 2015, pp. 27–29.

Turonian gas-bearing sediments (Kuznetsov suite) of Kharampurskoye oil field were formed in the environment of continuous post-Senomanian West Siberia transgression and can feature complicated chemogenic-terrigenous type of sedimentation. Considerable distance between the coast (around 300-400 km) and sediment sources allows predicting relatively deepwater sedimentation settings (around 150-200 m) below the storm wave base and predominantly pelitic sediment composition. However, the actual data of core (around 50 m) from the upper part of Kuznetsov suite (silty-clay composition, relics of wave structures and traces of rather intensive bioturbation of sediments) give evidence of shallow depths of sedimentation in the area of Kharampurskoye oil field. With great probability degree the depth of storm influence in flat epicontinental seas can be evaluated as 20-30 m. The results of topography paleoreconstruction and the analysis of regional tectonic trend also indicate the existence of the Kharampur arch during the Turonian period, with 150-180 m height relative to adjoining areas of the sea bottom. The amount of clastic material (fine silt) rhythmically thickens up the section. Swelling and non-swelling components of clays decrease. Layered carbonatization occurs in places. That all allows suggesting a local sea regression, increased eolian processes of clastic material transportation, and episodic invasion of fresh waters (cases of layered carbonatization) at the end of the Kuznetsov suite sedimentation process in Kharampurskoye oil field.

References

1. Atlas litologo-paleogeograficheskikh kart yurskogo i melovogo periodov Zapadno-Sibirskoy ravniny i Ob’yasnitel’naya zapiska k Atlasu (Atlas of lithologic and paleogeographic maps of Jurassic and Cretaceous periods of the West Siberian Plain and the Explanatory note to the Atlas): edited by Nesterov I.I., Tyumen’: Publ. of ZapSibNIGNI, 1976, 85 p.

2. Lisitsyn A.P., Lavinnaya sedimentatsiya izmeneniya urovnya okeana, pereryvy i pelagicheskoe osadkonakoplenie – global'nye zakonomernosti (Avalanche sedimentation of sea level changes, breaks and pelagic sedimentation - global patterns), Proceedings of 27th International Geological Congress, Part 3, Moscow, 1984, pp. 3–21.

3. Maloletko A.M., Evolyutsiya rechnykh sistem Zapadnoy Sibiri v mezozoe i kaynozoe (Evolution of the river systems of Western Siberia in the Mesozoic and Cenozoic), Tomsk: Publ. of TSU, 2008, 288 p.

4. Emel'yanov E.M., Bar'ernye zony v okeane: Osadko- i rudoobrazovanie, geoekologiya (Barrier zones in the ocean: sedimentary and ore formation, geoecology), Kaliningrad: Yantaryy skaz Publ., 1998, 416 p.

5. Kudamanov A.I., Geologicheskoe stroenie i usloviya formirovaniya otlozheniy valanzhina na primere produktivnykh plastov Surgutskogo svoda Zapadno-Sibirskoy plity (Geological structure and conditions for the formation of Valanginian deposits on the example of productive strata of the Surgut arch of the West Siberian plate): thesis of candidate of geological and mineralogical science, Tomsk, 2007.

6. Pemberton S.G., Spila M., Pulham A.J. et al., Ichnology & sedimentology of shallow to marginal marine systems, Newfoundland: Publ. of Geological Association of Canada, 1998, 641 p.

7. Geologiya i poleznye iskopaemye Rossii (Geology and minerals of Russia), Part 2: Zapadnaya Sibir' (Western Siberia): edited by Orlov V.P., St. Petersburg: Publ. of VSEGEI, 2000, 477 p.

The report represents the analysis of problems that confront specialized business subject to powerful competition and price containment in the context of import substitution. The period from the initiation of the import substitution program by the Russian Government in 2013 to 2016 was marked with an increase in quantity of the home contractors.

Authors of the report review outside and inside factors that service contractors should deal with on the markets of drilling fluids. These main factors include: ex-pansion of job geography, complication of drilling geology, shortage of qualified specialists, shortcoming of standardization in drilling fluids and materials etc.

The report contains classification of materials into bulk, special additives and pol-ymers. Details were given to three defined groups of polymer components of drilling fluids: polysaccharides, acrylic series synthetic polymers, modified humates and lignin sulfonates. In the work, authors present results of laboratory tests of materials for conformity with ISO 13500 and GOST Р 56946-2016.

The report contains the analysis of market of mud materials and chemicals, and general conclusions about issues of drilling fluids services in the context of import substitution. Special consideration is given to the higher education problems of training provision for mud engineers. Complications were also highlighted in certification and legal documentation for input check of materials and mud parameters.

Main conclusions were made related to cooperation of petroleum companies, en-gineering departments, developers of legal documentation, material producers, service contractors. This allows for import substitution in drilling fluids services.

References

1. Issledovanie rynka burovykh rastvorov i komponentov dlya burovykh rastvorov (Research of market of drilling fluids and components for drilling fluids), Moscow: AT Konsalting Publ., 2016, 497 p., URL: http://www.atconsult.ru.

2. Zakirov K., Russian oilfield services. Destination - sonsolidation (In Russ.), Neftegazovaya vertikal', 2013, no. 23–24, pp. 115–117.

3. Kryazhev V.N., Shirokov V.A., State of production of cellulose ethers (In Russ.), Khimiya rastitel'nogo syr'ya, 2005, no. 3, pp. 7–12.

4. Obzor rynka poliakrilamida (PAA) v Rossii (Overview of Russian polyacrylamide market), Moscow, 2015, 18 p.

The subject of the research is a down-hole drill string assembly with a steered downhole motor-deflector used in drilling of oil and gas wells. This assembly operates in two modes: steered and non-steered with the drill string rotation.

To improve the borehole quality and drilling cost performance it is necessary to reduce to a minimum the directional drilling which can be achieved through increasing the reliable ensuring the required intensity of the borehole deviation and enhancing the assembly steerability. To achieve this aim a technique is proposed for prediction of the assembly geometry parameters using the pattern allowing for contacting of its four supporting elements with the borehole bottom wall the path of which is a circle arc. The geometry parameters of the designed assemblies with drilling bits of diameters 215.9 and 220.7 mm and the downhole motor angularity of 1-1.5° can provide the borehole path with mean and major radii of curvature (200-600 m and more).

The results obtained enable to select the assembly design using permanent and movable centralizers as well as with a minimum negative effect on assembly’s manoeuvrability in a borehole and on the conditions of the borehole cleaning due to a reduced diameter of supporting-centralizing elements and their being manufactured as decentralizes (pads) on the downhole motor case.

References

1. Povalikhin A.S., Kalinin A.G., Bastrikov S.N., Solodkiy K.M., Burenie naklonnykh, gorizontal’nykh i mnogozaboynykh skvazhin (Directional, horizontal and multihole drilling), Moscow: Publ. of TsentLitNefteGaz, 2011, 645 p.

2. Prokhorenko V.V., Technology of horizontal wells and sidetracks drilling using a motor-deflector (In Russ.), Stroitel'stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2007, no. 11, pp. 2–4.

3. Grechin E.G., Pashkov E.V., Regulation of deformation and strain of the bottom-hole assembly, starting the motor diverter, by means of centralizers (In Russ.), Stroitel'stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2015, no. 5, pp. 18–21.

Today horizontal well drilling for hard-to-recover reserves is going with obligatory using of drilling steerable systems. The most technologically and economically justified is the use of telemetry systems that provide path control directly in the drilling process without lifting the tool to the surface. Modern systems make it possible to determine not only the inclinometric data, but also the technological characteristics of the drilling process and a number of properties of the formation.

The article examines the telemetric monitoring system of the wellbore trajectory, developed at the Perm National Research Polytechnic University. The device has the following features. The use of fiber optic gyroscopes with a closed loop as inclinometer sensors allows, firstly, to determine the azimuth and zenith angles of the well with high accuracy, secondly, to abandon the use of non-magnetic steels in the system casing and non-magnetic drill pipes in the column, and thirdly, to use the device when drilling near the casing of adjacent wells and magnetized rocks. The presence of a system for providing geostationary sensing elements makes it possible to use TMS in rotary drilling with an angular velocity of up to 250 min-1. The presence of a downhole turbine-generator and a set of rechargeable batteries provides the possibility of continuous operation of the device at the bottom. The system has two communication channels: hydraulic and cable in the wall of the drill pipe. The cable channel provides a data transfer rate of up to 1 Mb/sec.

The developed device is used for drilling directional and horizontal wells with a diameter of 216 to 227 mm, including rotary method. The system has no analogues in Russia for use in conditions of convergence with drilled cased wells and near magnetic disturbances.

References

1. Chernyshov S.E., Dolgikh L.N., Bolotov V.P., Features of directional wells construction considering the size of buffer zones on the Verkhnekamskoye potassium salt deposit (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2006, V. 5, no. 1, pp. 137–143.

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, V. 11, no. 3, pp. 89-93.

3. Nikolaev N.I., Kozhevnikov E.V., Enhancing the cementing quality of the well with horizontal profile (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2014, V. 13, no. 11, pp. 29-37.

4. Poplygina I.S., Opportunities of improved development of high-viscosity oil pool in Perm kray (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2014, V. 13, no. 11, pp. 57-66.

5. Zaynullin A.I., On the effectiveness of horizontal wells in the development of oil fields (In Russ.), Problemy ekonomiki i upravleniya neftegazovym kompleksom, 2007, no. 10, pp. 23-31.

6. Zaikin I.P., Kempf K.V., Murdygin R.V. et al., New technologies as a reserve of well construction technical and economical efficiency (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2010, no. 10, pp. 86-88.

7. Shevchenko I.A., Urgency of the use of downhole telemetry systems for directional well drilling for the development of offshore oil and gas fields (In Russ.), Nauchnaya perspektiva, 2014, no. 2, pp. 107-111.

8. Ryzhanov Yu.V., Wireless telemetry systems and equipment to control well drilling process parameters (In Russ.), Neft'. Gaz. Novatsii, 2014, no. 3 (182), pp. 38–41.

9. Karmanov A.Yu., Evaluation of drilling new wells Tournaisian-Famennian Magovskogo deposit facility (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2012, V. 11, no. 3, pp. 73-88.

10. Talipov R.N., Mukhametshin A.A., Technology of drilling two additional bores from horizontal part of directional well (In Russ.), Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo = Perm Journal of Petroleum and Mining Engineering, 2012, V. 11, no. 2, pp. 45-54.

11. Krysin N.I., Ryabokon' E.P., Turbakov M.S. et al., Improvement of devices of abrasive jet perforation in oil wells (In Russ.), Neftyanoe khozyaystvo = Oil Industry,  2016, no. 8, pp. 129-131.

12. Krysin N.I., Dombrovskiy I.V., Krivoshchekov S.N. et al., Study of fiber optic gyroscopes for telemetry systems of well trajectory monitoring (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 12, pp. 102-105.

13. Krysin N.I., Melekhin A.A., Dombrovskiy I.V. et al., Study of an information transmission channel in drill pipes during wells construction using rotary steerable system (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 11, pp. 80–82.

14. 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.

The influence of technological fluids filtrates on well productivity decrease is considered. There was established that natural residual water saturation of a layer changing due to filtrate penetration. It is determined that the technogenically modified residual water saturation consists of strongly bound (adsorbed) water saturation and conditionally mobile (capillary-jammed) water saturation. Such a structure of residual water saturation leads to changes in its values during well operation.

There suggested the models of residual water saturation changing under the action of a pressure gradient. The effects of a complex impact of jammed residual oil saturation and blocking of near wellbore part of formation as a result of colmatation on the values of the relative phase permeability are analyzed. The models taking into account the effect of these changes on the values of the relative phase permeability are proposed. There was developed a design model for taking into account the influence of a complex formation damage mechanism in near well-bore zones on well productivity. Analytic expressions for wells productivity in layers with an altered near wellbore zone are obtained.

The analysis of the obtained analytical solutions indicates a significant influence of considered factors on well productivity. The proposed solutions will make it possible to choose the way of action on near-wellbore zone adequately to its structure, to evaluate its efficiency, and to choose the optimal radius and intensity of the impact. The obtained results of the influence of jammed fluids will allow to estimate the productivity losses of the wells after putting them into operation after stopping.

References

1. Mikhaylov N.N., Physico-geological problems of additional recovery of residue oil in water-flooded reservoirs (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1997, no. 11, pp. 14.

2. Mikhaylov N.N., New lines of the raising of an informativity of geological and hydrodynamic deposit simulation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 3, pp. 69–73.

3. Kochina I.N., Mikhailov N.N., Filinov M.V., Groundwater mound damping, International Journal of Engineering Sciences, 1983, V. 21, no, 4, pp. 413–421.

4. Mikhaylov N.N., Chumikov R.I., Efficiency analyses of development of small fields with hard to recover reserves in Tatarstan (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2010, no. 2, pp. 74–76.

5. Mikhaylov N.N., Chumikov R.I., The effect of capillary-pinched phases on the permeability of reservoirs in the continuous phase (In Russ.), Burenie i Neft', 2009, no. 7–8, pp. 27–28.

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

7. Zaytsev M.V., Mikhaylov N.N., Borehole zone effect on well deliverability (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2004, no. 1, pp. 64–66.

8. 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.

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

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

The paper describes the application of a stochastic porous-network model, as well as the results of testing the developed software application. It was used to justify the porosity/absolute permeability function applied to simulate a group of Neocomian reservoirs in West Siberia poorly covered by core studies.

The discussed stochastic pore-network model of virtual rock samples was built in two stages. The first stage included a stochastic reconstruction of the void space. To do this, statistical data on the pore sizes obtained from capillary pressure curves was used. Due to the lack of detailed data on the microstructure of the pore space, a number of correlation and topological characteristics, such as the maximum connectivity radius (directly affects the coordination number), weight functions, etc., served as the tuning parameters. In the second stage, the absolute permeability was estimated based on the numerical flow simulation of single-phase incompressible fluid in pore channels. For this, the hydraulics equations were used: the equations of mass balance in pores and the equations for fluid flow in channels (the Poiseuille equations).

To appraise the poorly-cored target, a number of stochastic porous-network models were built with a detailed tuning by the available core data, taking into account the sample lithological descriptions. As a result of averaging a large number of model runs, the absolute permeability/porosity correlation function was updated. A new porosity/absolute permeability function was built which characterizes the rock as having the best reservoir properties in comparison with the previously justified function. The improved reservoir properties are also consistent with the logging data.

The use of the new function in a flow simulation model demonstrates a clearly improved match between the estimated and actual development data, which confirms the validity of the new petrophysical function.

References

1. Stepanov S.V., Kompleks vychislitel'nykh tekhnologiy dlya povysheniya kachestva modelirovaniya razrabotki neftyanykh i gazovykh mestorozhdeniy (Complex of computational technologies for improving the modeling quality of oil and gas fields development): thesis of doctor of technical science, Tyumen', 2016.

2. Okabe H., Pore-scale modeling of carbonates: PhD Thesis. London: Imperial College, 2004.

3. Zhizhimontov I.N., Mal'shakov A.V., The method of determining the coefficients of porosity and permeability of the rock on the basis of capillary pressure curves (In Russ.), Vestnik Tyumenskogo gosudarstvennogo universiteta. Fiziko-matematicheskoe modelirovanie. Neft', gaz, energetika, 2016, V.2, no. 1, pp. 72-81.

4. Blunt M.J., Physically-based network modeling of multiphase flow in intermediate-wet porous media, Journal of Petroleum Science and Engineering, 1998,  V. 20, pp. 117–125.

5. Mostaghimi P., Transport phenomena modelled on pore-space image: PhD Thesis. London: Imperial College, 2012.

Chemical methods of enhanced oil recovery (EOR) efficiency is associated with improved displacement of oil with original or slightly altered properties from unswept reservoir zones, and better displacement of mobile residual oil with high content of resin and asphaltene components from flushed zones. Studies on the effects of various production stimulation technologies remain important. The results of field-scale research provide the most valuable data necessary for feasibility studies and development of innovative technologies as well as for improvement of existing improved (IOR) and enhanced oil recovery methods.

The paper presents the results of comparative analysis of the composition and properties of crude oil samples collected before and after stimulation with the aim to improve sweep efficiency and oil recovery. To analyze oil composition, a number of physical and chemical methods were used including thermoanalysis, gas-liquid chromatography, gas-solid chromatography, infrared spectroscopy. It has been found that stimulation treatments promote oil displacement from unswept reservoir intervals containing oil with original or slightly altered properties. Injection of alkaline-polymer systems resulted in reduction of oil viscosity and asphaltene content while the content of middle distillates and light hydrocarbons increased. Similar changes were observed after application of integrated stimulation technology that consists in gel treatments followed by acid injection.

The results suggest that the applied technologies improve oil displacement from reservoir intervals and zones containing low-viscosity oil. These findings have been confirmed by well logging data. Chemical floods result in decrease of asphaltene content, increase of middle distillates and light hydrocarbons in produced oil, and overall mobilization of residual oil. Monitoring of composition and properties of produced oil makes it possible to understand the mechanisms of chemical EOR and confirms efficiency of chemical flooding.

References

1. Sabakhova G.I., Rafikova K.R., Khisametdinov M.R., Nuriev D.V., Zaripov A.T., Foreign experience in the application of enhanced oil recovery methods (In Russ.), Neft'. Gaz. Novatsii, 2015, no. 4, pp. 25-30.

2. Yusupova T.N., Romanov A.G., Barskaya E.E., Ganeeva Yu.M., Evaluation of the effects of encapsulated polymer systems on the formation using the changes in the composition of produced oil (In Russ.), Elektronnyy nauchnyy zhurnal Neftegazovoe delo, 2007, URL: http://www.ogbus.ru/ authors/ Yusupova/Yusupova_1.pdf

3. Yusupova T.N., Petrova L.M., Ganeeva Yu.M. et al., Use of thermal analysis in identification of tatarstan crude oils (In Russ.), Neftekhimiya = Petroleum Chemistry, 1999, V. 39, no. 4, pp. 254–259.

4. Aspekty geneticheskikh svyazey neftey i organicheskogo veshchestva porod (Aspects of the genetic relationships of oils and organic matter of rocks): edited by Eremenko N.A., Maksimov S.P., Moscow: Nauka Publ., 1986, 134 p.

5. Sovremennye metody analiza v organicheskoy geokhimii (Modern methods of analysis in organic geochemistry): edited by Kontorovicha A.E., Novosibirsk: Publ. of SNIIGGiMS, 1973, 100 p.

6. Rybak B.M., Analiz nefti i nefteproduktov (Analysis of oil and oil products), Moscow: Gostoptekhizdat Publ., 1962, 888 p.

7. Yusupova T.N., Barskaya E.E., Ganeeva Yu.M., Romanov A.G., Development of methodology for producing fields crude oil typing (In Russ.), Tekhnologii nefti i gaza, 2010, no. 1, pp. 46–53.

Heavy oil and natural bitumen deposits development is especially relevant nowadays. One of the highly efficient techniques for the development of such deposits is the steam-assisted gravity drainage (SAGD) method.

This work has two main objectives. The first is to build the geochemical model of a deposit on vertical and horizontal gradients of the relative content of biomarkers. And the second is to assess the feasibility of applying the derived model to monitor the development of superviscous oil deposits in the Karmalskiy deflection of the Cheremshanskoye deposit, where the SAGD technology is currently applied.

The experimental part of work consists of the extraction of 35 core samples fr om the 8 oil well pumps, extraction of the saturated factions from the bitumen and the gas chromatography-mass spectrometry (GCMS) analysis of the selected factions in the TIC mode.

The relative concentration of 6H-Farnesol (HHF) to Phytane (Ph) was selected as a simulation parameter. Laboratory studies have shown that the HHF/Ph ratio is shown in horizontal and vertical gradients due to biodegradation of the organic matter throughout the whole studied area. It is also noted that in almost all wells there is a sharp increase in the HHF/Ph value at the bottom of the productive layer at a depth of 150 to 160 meters, wh ere the most intense biodegradation of the organic matter occurs. Laboratory studies have shown that the HHF/Ph ratio is stable in the context of hydrothermal processing under pressure, which indicates that it can be measured in the superviscous oil produced by the SAGD method for subsequent comparison with the geochemical model.

Based on the constructed model and measured HHF/Ph ratios in the extracted superviscous oil, authors have assessed the likely ways of its tributaries to the extractive wells.

References

1. Khisamov R.S., The analytical model for development of heavy oil deposit by steam-assisted gravity drainage method (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 2, pp. 62–64.

2. Bennett B., Adams J., The controls on the composition of biodegraded oils in the deep subsurface, Part 3. The impact of microorganism distribution on petroleum geochemical gradients in biodegraded petroleum reservoirs, Organic Geochemistry, 2013, V. 56, pp. 94–105.

3. Peters K.E., Walters C.C., Moldowan J.M., The biomarker guide, Cambridge U.K.: Cambridge University Press, 2005, 1155 p.

4. Feoktistov D., Sitnov S., Vahin A. et al., The description of heavy crude oils and the products of their catalytic conversion according to SARA-analysis data, International Journal of Applied Engineering Research, 2015, V. 10, pp. 45007 – 45014.

5. Sitnov S.A., Feoktistov D.A., Kayukova G.P. et al., Catalytic intensification of in-situ conversion of high-viscosity oil in thermal steam extraction methods, International Journal of Pharmacy and Technology, 2016, V. 8 (3), pp. 14884–14892.

6. Vakhin A.V., Onishchenko Ya.V., Chemodanov A.E. et al., Thermal transformation of bitumoid of Domanic formations of Tatarstan (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 10, pp. 32–34.

7. Sitnov S.A., Petrovnina M.S., Feoktistov D.A. et al., Intensification of thermal steam methods of production of heavy oil using a catalyst based on cobalt (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 11, pp. 106–108.

8. Petrov S.M., Zakiyeva R.R., Ibrahim Abdelsalam Ya. et al., Upgrading of high-viscosity naphtha in the super-critical water environment, International Journal of Applied Engineering Research, 2015, V. 10 (24), pp. 44656–44661.

9. Sitnov S.A., Feoktistov D.A., Petrovnina M.S. et al., Structural changes of heavy oil in the composition of the sandstone in a catalytic and non-catalytic aquathermolysis, International Journal of Pharmacy and Technology, 2016, V. 8 (3), pp. 15074–15080.

10. Onishchenko Ya.V., Vakhin A.V., Voronina E.V., Nurgaliev D.K., Thermo-catalytic destruction of kerogen in the presence of cobalt oxide nanoparticles and mineral pyrite (In Russ.), SPE 181915-MS, 2016.

From 2014 to 2017 number of hydraulic fracturing operations performed in low-permeability oil reservoirs (permeability less than 0.01 mkm2) in the Nenets autonomous district oil fields were increased. Effective hydraulic fracturing performance in low-permeability reservoirs requires creation of fractures with greatest possible length that increases the extent of fluid movement due to increasing amount of injected proppant. However, there are several problems related to high pressure while hydraulic fracturing performance and intense pressure increase while proppant injection in reservoirs occur at depths more than 3000 m. In this article experience of the hydraulic fracturing performance using proppant in low-permeability terrigenous and carbonate reservoirs of Devonian system on the Nenets autonomous district oil fields was considered. Also functions of technological parameters, reservoir properties and well workover performance criterion are provided in this paper. Inverse dependence was educed between specific consumption of proppant and well-head pressure while hydraulic fracturing. The calculation example of vertical and minimum horizontal components of geostatic pressure using the core laboratory research and field research indicates the probability of the formation of horizontal fractures was provided. The example of two unsuccessful attempts of hydraulic fracturing in well in low-permeability carbonate reservoir and successful fracturing performance after process optimization which resulted in achievement planned increment oil rate was demonstrated. Main options of hydraulic fracturing technology efficiency increasing were also considered in this paper.

References

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

2. Kashnikov Yu.A., Shustov D.V., Kukhtinskiy A.E., Kondrat'ev S.A., Geomechanical properties of the terrigenous reservoirs in the oil fields of Western Ural (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 4, pp. 32-35.

3. Dobrynin V.M., Deformatsii i izmeneniya fizicheskikh svoystv kollektorov nefti i gaza (Deformations and changes in the physical properties of oil and gas collectors), Moscow: Nedra Press., 1970, 239 p.

4. Kashnikov Yu.A., Ashikhmin S.G., Shustov D.V. et al., In situ stress in the oil fields of Western Ural (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 5, pp. 64-66.

5. Kondrat'ev S.A., Zhukovskiy A.A., Kochneva T.S., Malysheva V.L., Opyt provedeniya proppantnogo gidrorazryva plasta v karbonatnykh kollektorakh mestorozhdeniy Permskogo kraya (Experience of proppant hydraulic fracturing in the carbonate reservoirs of the Perm Region), Moscow: Publ. of VNIIOENG, 2016, 68 p.

The paper is devoted to the serious problem of water shut off in well production. One of the ways to solve the problem is to conduct the waterproofing works using cement slurries based on synthetic resins, for example, formulations based on urea-formaldehyde resin (UF), which have a number of advantages in properties compared to traditional cement slurries. They are widely used in many areas of production, including in the oil and gas industry, because of such qualities as: high adhesiveness and durability; simplicity of preparation; low toxic properties; low cost; rich raw material base. The paper presents laboratory studies on the development and implementation of the quick-setting cement slurry (QSCS) based on UF for reservoir temperatures from 20 to 100 ° C with adjustable time of thickening and setting – from 15 min to 8 h. The rheological properties were studied; the selection of formulation of the QSCS composition and hardener was made. Studies were carried out on the compatibility of the QSCS with the alkaline polymer clay-silica system (APCSS), which is used for waterproofing works as a block screen. Practical implementation of the QSCS in conjunction with the APCSS for the liquidation of water inflows was carried out at well No.36 of the South-Okhteurskoe deposit, water cut was reduced from 98 to 85%, an increase in oil production of 6 tons per day was obtained. On the date of the analysis the well worked with the effect for more than two years, the accumulated production amounted to 3,500 tons of oil. The polymeric backfill composition of the QSCS and the technology with polymer compositions ensure a high efficiency of gas and water shut off in wells with reservoir temperatures of 20 to 120 degrees.

References

1. Azarov V.I., Grishin S.P., Tsvetkov V.E., Metodicheskie ukazaniya k laboratornym rabotam po tekhnologii sinteticheskikh smol i kleev (Methodological guidelines to laboratory works on synthetic resins and glues technology), Moscow, 1978, 31 p.

2. Patent no. 1620610 USSR, E 21 B 33/138, Polimernyy tamponazhnyy sostav dlya izolyatsii zon pogloshcheniya (The polymer composition of the backfill for isolate the absorption zones), Inventors: Abdurakhimov N., Dzhalilov A.T., Fayziev Sh.G., Samigov N.A., Erkinov A.S., Lykov E.A.

3. Patent no. 2167267 RF, E 21 B 33/138, Backfilling material, Inventors: Pavlychev V.N., Umetbaev V.G., Emaletdinova L.D., Prokshina N.V., Strizhnev K.V., Kamaletdinova R.M., Strizhnev V.A., Nazmetdinov R.M., Merzlyakov V.F., Volochkov N.S.

4. Patent no. 2439119 RF S2 MPK S09K 8/44, Quick-setting backfilling mix for water and gas inflow insulation in low-temperature oil and gas wells, Inventors: Abdurakhimov N.A., Apasov T.K., Yusulbekov A.Kh., Apasov G.T.    

Automated group metering stations, the construction and maintenance of which requires large capital investments, are used to measure well flow rates in Samaraneftegas JSC. With the temporary inoperability of automated group metering stations, mobile metering units are used to determine the flow rates for a few hours; however, each metering requires large operating costs. The use of metal-consuming and expensive automated group metering stations for measuring the flow rate at the current stage of technology development is not so promising, at the same time, the use of mobile metering units significantly increases the cost of oil production. Consequently, the development and testing of new technologies for flow rates measuring, allowing to reduce capital investments and operating costs, is an urgent task. To solve this important task, a compact device is needed that allows instrumental measurements directly in the well to provide instantaneous and accurate readings of fluid flow. The most promising direction is the use of submersible flowmeters. To obtain instantaneous data on the well flow rate, it is possible to use a device installed on downhole equipment. One way to implement such measurements is based on the use of individual measuring devices based on flowmeters - termomanometric systems with a built-in fluid metering unit.

Specialists of Samaraneftegas JSC developed an improved termomanometric system with a built-in flowmeter. The article deals with the design and operation principle of termomanometric system with a built-in flowmeter. The efficiency and effectiveness of termomanometric system with a built-in flowmeter for flow rate determination in combination with various control stations are confirmed by the data obtained at the automated prover, as well as by the results of pilot tests of three installations run down the wells of Samaraneftegas JSC. Their current run period exceeded 150 days. The given technical solution allowed to increase the energy efficiency of production, to reduce the number of failures and repairs of downhole pumping equipment, to optimize the chemical reagents dosing system without significant additional costs.

References

1. Gilaev G.G., Strunkin S.I., Pupchenko I.N. et al., Tekhnika i tekhnologiya dobychi nefti i gaza OAO “Samaraneftegaz” (Technique and technology of oil and gas production of Samaraneftegas JSC), Samara: Neft'. Gaz. Innovatsii Publ., 2014, 528 p.

2. Ivanovskiy V.N., Monitoring and control systems or intelligent oil production systems. What is the future for? (In Russ.), Inzhenernaya praktika, 2014, no. 3, pp. 42–44.

4. Ivanovskiy V.N., Sabirov S.A., Gerasimov I.N., Klimenko K.I., Intellectualization of oil production: new opportunities, developments and trends, a system for monitoring the operating indicators of a mechanized well stock (In Russ.), Inzhenernaya praktika, 2014, no. 7, pp. 60–63.

5. Shevchenko S.D., Yakimov S.B., Ivanovskiy V.N. et al., Development of the algorithm providing calculation of oil wells flow-rates operated by means of usage of electrical submersible pumps (In Russ.), Oborudovanie i tekhnologii dlya neftegazovogo kompleksa, 2013, no. 6, pp. 90–91.

The work shows an especial case of streaming corrosion behavior of submarine pipeline systems on the White Tiger oilfield (offshore of Vietnam). Based on the results of visual inspection it was identified a presence of а «groove» with width up to 60 mm on the bottom of the pipeline. A reduction in the pipeline wall thickness at the 6 o’clock position was more than 85 %. The specific “tubercles” of the numerous sulfate-reducing bacteria colonies were also found on the inner surface of the pipeline, which would lead to the formation of the round-shaped defects (pits) in place, which sizes were 50-400 micrometers. The possible reason for increasing of micro-organism’s activity is possibly due to a periodical exploitation of the pipeline for reservoir pressure maintenance with a stoppage of prepared water pumping and finding dead lost-circulation zone. The presented results of composition analysis and the metal strength characteristics test within the defected zone of the pipe comply with the steel (X60 APIv5L). It was found that, the main components of the hard deposits on the inner surface of the pipeline were iron sulfates and sulfides content of which is more than 60 % by weight.

It was assumed, that the initial stage of further crevice corrosion development was a growth of sulfate-reducing bacteria colonies, which resulted in formation of loose layers of iron sulfates and sulfides sludges. If the sludges peeled off (because of them baseline adhesiveness to the metal surface), then in this case the sludges can become like an abrasive material. The sludges altogether with water flow remove the protective layer of inhibitor corrosion film and the metal oxides layer up the bare metal on the bottom of the pipeline. Then electro-chemical corrosion occurs in participation with coupled metals (galvanic pair) “metal (anode) – corrosion product (cathode)” and with a growth of corrosion up to 10-15 mm/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. Abdullin I.G., Gareev A.G., Mostovoy A.V., Korrozionno-mekhanicheskaya stoykost' neftegazovykh truboprovodnykh sistem: diagnostika i prognozirovanie dolgovechnosti (Corrosion-mechanical resistance of oil and gas pipeline systems: diagnostics and prediction of durability), Ufa: Gilem, 1997, 177 p.

3. Moiseeva L.S., Kondrova O.V., Biocorrosion of oil and gas field equipment and chemical methods for its suppression, Part 1 (In Russ.), Zashchita metallov= Protection of Metals and Physical Chemistry of Surfaces, 2005, V. 41, no. 4, pp. 417–426.

4. Peabody A.W., Peabody’s control of pipeline corrosion, Houston: NACE Press, 2001, 47 p.

5. 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.

The development of oil rims (sub-gas zones) of oil-and-gas and oil-gas-condensate deposits is complicated by the multiphase flow in the formation, which leads to the emergence of negative processes such as pushing oil into the gas zone, breaking gas to the bottom of the producing well (increase in the gas factor is more than 1500 m3/t). As a result, oil recovery does not exceed 10% of the initial reserves.

A potential rise of oil vapor pressure is up to 66.7 kPa, so it is possible to increase a yield of commercial oil due to a change in separation regimes and the extraction of heavy hydrocarbons from low-pressure gas.

If oil vapor pressure exceeds values of 66.7 kPa, two methods for its reduction are possible: additional heating, for example in furnaces, or stripping of light oil components with gas, for example, feeding the first stage separation gas to the separator.

It is established that an increase in the heating temperature in comparison with blowing allows a greater yield of commercial oil, but requires more energy. Thus, when a gas-oil ratio is up to 750 m3/t, it is economically more profitable to heat oil (the profit from additional oil extraction exceeds the cost of energy supply). When the gas-oil ratio exceeds 750 m3/t, the blowing process is preferred in the process of development due to the reduction of energy costs.

A combination of technical solutions and techniques for controlling a pressure of saturated oil vapor allows to reduce losses (increase the yield) of commercial oil.

References

1. Ivanov S.S., Maksimov Yu.V., Features of modeling material and thermal calculation of oil separation process for oil rims (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 12, pp. 87–89.

The gas bubbles in the turbulent flow of the liquid are polydisperse. Their diameter, as a rule, obeys the law of the normal logarithmic distribution, which is completely determined if the maximum particle size of the dispersed phase is known. Its value, in turn, depends on the ratio of the sizes of the bubbles held by the flow due to the vibrations of the moles of the liquid and the bubbles that can exist in the flow without breaking down. The article shows that the question of these characteristic diameters of gas bubbles has not been adequately studied at present. In deriving the calculation formula for the maximum diameter of a gas bubble, which the turbulent flow can hold, the authors have taken into account that the ascent of each individual gas inclusion in the gas-liquid flow slows down as a result of interaction with neighboring bubbles. To this end, the dynamic viscosity of the dispersion medium was replaced by the effective viscosity of the gas emulsion. In addition, from the empirical formula describing the weighted flows, a correction factor was taken, taking into account the occurrence of an additional restraining force when the moles of liquid fluctuate. Considering the crushing of suspended bubbles by turbulent pulsations, the authors have shown that the existing design formulas for particles in a dispersed phase (droplets, gas bubbles) are often distinguished only by the magnitude of the proportionality coefficient. A more reliable value of this coefficient was obtained by processing experimental data on the diameter of gas bubbles in tubing using gas lift. At the same time, the coefficient of hydraulic resistance was used as a measure of the energy dissipation in the pipes. Approbation of the calculated dependencies was performed by comparing the simulation results with the diagrams of the conditions for the existence of the oil-gas flow emulsion structure in horizontal pipes constructed by professor A.I. Guzhov and his students on the basis of visual observations in the conditions of oil industry. It is shown that, in general, the proposed formulas describe the experimental points with satisfactory accuracy. The existing discrepancies may be associated with inaccurate information about the properties of phases, as well as the subjectivity of the perception of flow structures by the observer.

References

1. Il'ichev V.I., Neuymin G.G., On the law of the distribution of the dimensions of gas bubbles in a turbulent flow of a liquid (In Russ.), Akusticheskiy zhurnal, 1965, V. 2, V. 4, pp. 453–457.

2. Tronov V.P., Rozentsvayg A.K., Intensification of the emulsion stratification by integration of the dispersed phase in the turbulent regime (In Russ.), Sbor, transport i podgotovka nefti, 1974, V. 29, pp. 21–31.

3. Takahashi Katsuroku, Ohtsubo Fuj io, Takauchi Hiroshi, Mean drop diameters of W/O- and (W/O)/W-dispersions in an agitated vessel, Kokagu kogaky ronbunshu, 1980, V. 6, no. 6, pp. 651–656.

4. Novozhilova D.V., Calculation of the aerosols disperse composition according to two average dimensions (In Russ.), Kolloidnyy zhurnal, 1963, V. 25, no. 2, pp. 206–208.

5. Moretskiy V.Yu., Varybok D.I., Savinov S.A., Break-down of arbitrary discontinuity on the boundary of structure change of hydrocarbon gas and liquid mixture flow in pipeline (In Russ.), Nauka i tekhnologii truboprovodnogo transporta nefti i nefteproduktov, 2012, no. 2, pp. 48-55.

6. Zholobov V.V., Moretskiy V.Yu., Tarnovskiy E.I., Shiryaev A.M., Modeling of gas piston flow in the process of filling of the pipeline (In Russ.), Nauka i tekhnologii truboprovodnogo transporta nefti i nefteproduktov, 2012, no. 4, pp. 56–63.

7. Medvedev V.F., Dispersion of occluded gas (In Russ.), Zhurnal prikladnoy khimii, 1979, V. 52, no. 9, pp. 2122–2124.

8. Korshak A.A., Metody rascheta osnovnykh parametrov gazonasyshchennoy nefti (Methods for calculating the main parameters of gas-saturated oil), deposit manuscript of VNIIOENG no. 1878, Ufa, 1990, 40 p.

9. Pishchenko I.A., Nekotorye teoreticheskie soobrazheniya o strukture raschetnykh formul dlya opredeleniya kriticheskikh skorostey pri dvizhenii vzvesenesushchikh potokov v gorizontal'noy tsilindricheskoy trube (Some theoretical considerations on the structure of computational formulas for the determination of critical velocities in the motion of suspended flows in a horizontal cylindrical tube), Collected papers “Issledovanie odnorodnykh vzvesenesushchikh turbulentnykh potokov” (Investigation of homogeneous suspension-bearing turbulent flows), Kiev, 1967, pp. 80–86.

10. Kolmogorov A.N., On the fragmentation of drops in a turbulent flow (In Russ.), DAN SSSR, 1949, V. 66, no. 5, pp. 825–828.

11. Levich V.G., Fiziko-khimicheskaya gidrodinamika (Physico-chemical hydrodynamics), Moscow: State Publishing House of Physical and Chemical Literature, 1959, 699 p.

12. Shinnar R., Churh J.M., Predicting particle size in agitated liquid-liquid despersions, Ind. and Eng. Chem., 1960, V. 52, no. 3, pp. 253–256.

13. Sertificate of authorship no. 508641 SSSR, MKIF17D 1/16, Sposob transportirovaniya zhidkostey i suspenziy (The method of transporting liquids and suspensions), Author: Bespalov A.A.

14. Borodin Yu.A., Eksperimental'noe issledovanie gazoneftyanogo potoka v liftovykh trubakh (Experimental study of gas and oil flow in the tubing): thesis of candidate of technical science, Moscow, 1975.

15. Guzhov A.I., Sovmestnyy sbor i transport nefti i gaza (Gathering and transportation of oil and gas), Moscow: Nedra Publ., 1973, 280 p.