Articles

Oil production

Approaches to integrating interpretation of hydrodynamic studies with well-geophysical and laboratory studies for horizontal wells with multistage hydraulic fracturing of reservoirs

Samoylov A.S., Votchel V.A., Egorova A.P., Mokina D.S.

DOI: 10.24412/2076-6785-2024-3-41-48

Abstract
Well tests are an important tool for determining the reservoir properties, but for gas and gas condensate reservoirs they are one of the tools for reliable determination of the well productivity factor in the dynamics of operation and the influence of technogenic fractures of multistage hydraulic fracturing on it, both as a tool for flow stimulation and increasing hydrocarbon yield of the reservoir. In this regard, the issue of reliable assessment of all operating parameters of the well from the position of the amount of resources invested in it is particularly relevant nowadays the widespread use of high-precision digital solutions. In addition to making operational decisions on well operation management, the strategic goal of well testing in the system of field geophysical control is to obtain information that allows, in conjunction with other geological and field data, to form reliable views of the system productive formation - fracture well, and to provide detailed digital models of the field for monitoring field development and refining the development strategy.
The article presents an example of multidisciplinary interaction between specialists in hydraulic fracturing, geomechanical modeling, interpretation of field-geophysical and wells testing, laboratory studies of hydraulic fracturing fluids and materials, as well as specialists in field development for reliable determination of geometric and conductive characteristics of technogenic fractures and their contribution, using the example of one of the horizontal gas-condensate wells in an East Siberian field.

Materials and methods
    The article was written using data of field geophysical studies, engineering reports on hydraulic fracturing, results of interpretation of noise and thermometry, as well as analysis of laboratory studies on fluids and materials for hydraulic fracturing at a horizontal well in the East Siberian field.
    Interpretations of gas-dynamic studies of wells with fracturing of one of the gas condensate fields, by summarizing and analyzing the results of fracturing designs, laboratory studies of fracturing fluids and proppants, geomechanical modeling and taking into account the results of determining the flow profile.

Keywords
hydrodynamic studies of wells, conductivity, technogenic fracture, horizontal well, multistage hydraulic fracturing

Justification of the selection of the optimal size of inflow control devices for the development of oil and gas reservoirs

Roslyakov K.S., Abdullin A.A., Muslimov B.S., Islamov R.R.

DOI: 10.24412/2076-6785-2024-3-30-34

Abstract
The article presents an approach for selecting the optimal type and number of autonomous inflow control devices (AICD) for the development of oil and gas deposits using multivariate hydrodynamic modeling.
According to the results of multivariate modeling, it was noted that the optimal option for completing a well with an AICD according to the criterion of accumulated production and accumulated discounted net income (NPV) varies depending on the bottom-hole pressure, and vice versa,
the optimal amount of AICD depends on the selected bottom-hole pressure.
The advantage of the proposed approach is that when selecting the layout of wells, various options for completion with AICD are modeled,
the volume of produced products and its dependence on the downhole pressure are taken into account, together with the economic component, the best completion option is determined from the point of view of economic efficiency.
For calculations, a software package was used that allows segmentation and calculation of wells with inflow control devices (developed at RN-BashNIPIneft LLC).

Materials and methods
Materials: characteristics of inflow control devices, sector hydrodynamic model.
Methods: analysis of the results of multivariate hydrodynamic modeling.

Keywords
inflow control device, sector hydrodynamic model, multi-segment well, oil and gas field

Search for the optimal proppant weight when carrying out multi-stage hydraulic fracturing in horizontal wells

Zharkova K.V., Pupkov N.V.

DOI: 10.24412/2076-6785-2022-8-87-92

Abstract
This article discusses an engineering approach to substantiate the optimal mass of injected proppant for horizontal wells with multi-stage hydraulic fracturing.
The object of study is a classic low-permeability reservoir with permeability characteristic of the area and the use of multi-stage hydraulic fracturing technology to bring reserves into development. The volumes of proppant injected into the reservoir at each stage of hydraulic fracturing are determined empirically.
In the course of the work, an approach was selected based on static analysis and averaging of data from a large volume of hydraulic fracturing.
In this work, a system of engineering justification of the maximum mass of proppant injected into the reservoir has been developed and the economic profitability limit of increasing the volume of fractures has been established.

Materials and methods
The experience of hydraulic fracturing at the field was summarized, the optimal proppant mass was substantiated to achieve the best TEC of wells, the actual hydraulic fracturing operations performed at the field were studied and analyzed, the dependences of the fracture geometry parameters on the proppant mass were established, allowing to correctly model the fracture parameters and the best parameters for various zones were determined saturation of the object according to technical and economic indicators.

Keywords
low permeability, multi-stage hydraulic fracturing, horizontal well, proppant

Low-permeable oil and water zones to be developed by horizontal wells with multistage hydraulic frac or by multilateral wells?

Ermakov P.V., Khazipov R.L., Reshetnikova D.S., Patrakov D.P., Zharkov A.V., Nabokin I.R., Fitsner A.F., Burdin A.V.

DOI: 10.24412/2076-6785-2022-8-82-86

Abstract
RN-Nyaganneftegaz JSC owns the license for oil production at the Em-Egovsky and Kamenny license blocks of Krasnoleninskoye oil and gas condensate field with unique reserves.
To date, 61 % of oil is produced from VK13 reservoir (vikulovskaya formation), and the volume of current recoverable reserves is 34 %
of the fields total reserves. About 70 % of the vikulovskaya formation reserves are concentrated in the undeveloped edge zones at lower regions of the reservoir structural top, and they remain the main source for maintaining oil production.

Materials and Methods
This paper provides an overview of the drilling and development experience horizontal wells and multilateral wells, as well as well completion technologies applied for effective development of VK13 reservoir edge zones within Kamenny license block, which is a testing ground for pilot projects.

Keywords
drilling, development, edge zones, under-saturated reservoir, horizontal wells, multi-lateral wells

The strategy of planning pilot works to prepare tight reserves of a unique field for the development at the exploration stage

Ankudinov A.A., Arkhipov V.N., Starikov M.A., Sorokin A.V.

DOI: 10.24412/2076-6785-2022-8-76-80

Abstract
The paper considers an approach to the development of a unique field, which reserves are characterized by significant heterogeneity,
low permeability, abnormally high reservoir pressure. According to the geological characteristics, the reserves are hard to recover.
The strategy selection for full-scale development is planned to be made based on the results of technology testing at the sites of pilot works.
The paper proposes an approach to stage-by-stage planning from simple to complex, which allows risks mitigation during the implementation of work and reducing decision-making time.

Materials and methods
The justification of the pilot sites of the field under consideration
is given, tested technologies are selected. A detailed research program is developed, including all advanced methods for tight reserves. A strategy for the development of reserves is formed, key points
for obtaining information are identified.

Keywords
tight reserves, low permeability, pilot project

Aspects of technological solutions for the development of tight reserves deposits characterized by ultra-low permeability and the presence of abnormally high reservoir pressure

Ankudinov A.A., Arkhipov V.N., Starikov M.A.

DOI: 10.24412/2076-6785-2022-8-70-74

Abstacrt
Tight reserves are characterized by unfavorable conditions for recovery from the position of oil properties or conditions of occurrence (concentrated in deposits of low-permeable reservoirs). At the moment, production is carried out mainly from traditional reservoirs, but as a rule, it is complex reserves that provide the main increase in the resource base of oil companies. The development of tight reserves requires the use of new technologies and significant capital investments. Deposits of unconventional reservoirs are characterized by high variability of geological feature and formation reservoir properties depending on the region, which dictates the need to develop an individual approach to their development.
The authors of the article, using the example of oil field located in the Arctic zone of Russian Federation, consider an approach to the development of technological solutions for the development of a tight reserves characterized by low permeability, high heterogeneity and the presence of abnormally high reservoir pressure.

Materials and methods
The analysis of production experience from tight reserves is carried out, the key aspects of the development of low-permeability reservoirs are identified. An approach to testing formation hydraulic fracturing technologies, the development of well completion for multistage formation hydraulic fracturing is given. Potentially effective agents for the development of tight reserves are identified, a program of laboratory studies is created to remove uncertainties.

Keywords
tight reserves, low permeability, formation hydraulic fracturing

Application of the results of modeling of technological measures in specialized software for the management of fishing infrastructure facilities

Fomenko I.Sh., Brinster V.M., Mezentseva T.A., Mamonov D.M., Pavlov V.P.

DOI: 10.24412/2076-6785-2022-8-66-69

Abstract
At the late stage of field development, there is a decrease in production volumes compared to the design capacity of the infrastructure, which leads to the risks of liquid accumulation in the elements of the formation well plume system. To eliminate potential problems, it is important to identify the places of fluid accumulation in a timely manner and plan measures to ensure the stable operation of pipelines [3, 4].

Materials and methods
The article discusses the operation of the gas collection network with parameters corresponding to typical conditions for deposits in the final period of the development of the object.
The obtained results can be applied to substantiate the implementation of technological measures in the fields.

Keywords
gas field management, gas production, production engineering, dynamic modeling, technological regime

Four stages of production redistribution at the multilayer field X under conditions of multiphase filtration

Ufimtseva M.N.

DOI: 10.24412/2076-6785-2022-8-60-64

Abstract
The management of several reservoirs by a single grid of wells does not always allow the correct accounting of hydrocarbon production.
The well-known and most used production redistribution methods do not take into account the component-by-component distribution of produced hydrocarbons. Methods mainly used are based on formation conductivity and net oil pay of the zone. Therefore, there is a practical need for an analytical tool that would be based on reliable and available data and could sufficiently and efficiently solve the problems associated with the separation of produced fluids.

Materials and methods
A methodology developed on the basis of combining existing tools to enhance the ultimate oil recovery by determining the containment area of residual reserves based on the analysis and revision of field data.

Keywords
redistribution of production, containment area of residual reserves, multilayer formation, accountability of reserve recovery

Modern technologies for prospecting and preparation for the development of hard-to-recover hydrocarbon reserves in the Arctic zone

Arzhilovskiy A.V., Arkhipov V.N., Shirokov A.S., Grandov D.V.

DOI: 10.24412/2076-6785-2022-8-53-59

Abstract
The article describes approaches to the implementation of the integrated strategy of NK Rosneft PJSC (Company) in the field of geological exploration, preparation for the bringing into development of a large project (Project) located in the Arctic zone of the Russian Federation, at a considerable distance from infrastructure facilities. Predominantly, the hydrocarbon potential of the assets under consideration is associated with reserves belonging to the category of tight reserves. Their development requires the application and development of modern technologies in related fields geology, seismic exploration, drilling, geophysics, well survey, development.

Materials and methods
Specialized methods of field geophysics, core and reservoir fluid studies are applied to ensure the effective development of tight deposits. Based on the results of the conducted research, complex geological, petrophysical and geomechanical models are constructed that allow implementing a targeted approach to the development.

Keywords
tight reserves, pilot project, infrastructure

Investigating the aquathermolysis process of heavy oil from the Yarega field in the presence of iron tallate

Sitdikova G.Kh., Mukhamatdinov I.I., Vakhin A.V.

DOI: 10.24412/2076-6785-2024-2-53-56

Abstract
The article presents the results of studies on the thermal steam treatment on samples of bituminous rock from the Yarega field with and without the presence of an iron-based catalyst precursor. After each experiment conducted in a high-pressure reactor, bitumenoid was extracted from the rock, and a complete analysis of the composition and properties of the obtained oil, gas, and rock was carried out. Based on the conducted research, it is shown that the application of an aquathermolysis catalyst will improve the component composition and refine it under reservoirconditions.

Materials and methods
Oil-bearing rock from the Yarega field, iron tallate, gas phase analysis, bitumoid extraction, analysis of the oil's group composition (SARA analysis), scanning electron microscopy.

Keywords
catalyst precursor, aquathermolysis, oil-bearing rock, thermal steam treatment (TST), bitumoid, oil upgrading

Calculation of PVT-properties of reservoir fluids by modified correlations based on the results of laboratory studies of samples of oil, oil and gas and oil and gas condensate deposits in the territory of activity of RN-Purneftegaz LLC

Ishmuratov T.A., Islamov R.R., Sharipova G.F., Abdulmyanov A.R., Khamidullina A.I., Khisamov A.A., Andreev A.E., Opritov I.G.

DOI: 10.24412/2076-6785-2024-2-42-48

Abstract
The paper shows that the correlations used in calculating reserves or forecasting oil and gas production volumes can be modified based on laboratory samples, which increases the accuracy of their PVT properties. This made it possible to identify problematic objects in which the gas content values were underestimated or the volume coefficients were overestimated, as well as to exclude from the selection program layers whose PVT properties coincided with the values determined by modified correlations.

Materials and methods
Materials: results of laboratory examination of deep samples.
Methods: calculation of PVT properties of the formation by authors correlations, estimation of the average deviation of experimental data from calculated PVT properties of formations, optimization of correlation parameters by the Newton method based on laboratory sample data.

Keywords
PVT-properties, correlation, modified correlation, oil and gas, correlation applicability matrix

Selecting a horizontal well completion system with multi-stage hydraulic fracturing

Islamov R.A., Andreev E.Yu., Volkov M.G

DOI: 10.24412/2076-6785-2024-2-34-38

Abstract
Oil production from low-permeability reservoirs with permeability less than 10-15 m2 requires specialists to develop new approaches to calculate the performance of horizontal wells with multistage hydraulic fracturing. Heterogeneous structure and distribution of reservoir properties and overlapping intervals of nonreservoir, trajectory of horizontal well section, intervals of fracture initiation and hydraulic fracture design, fluid leakage into the reservoir, interference with neighboring wells should be taken into account. Previously developed numerical methods do not allow to take into account all the above factors, their improvement is required. The article describes a method for designing a horizontal well completion system with multistage hydraulic fracturing. The method takes into account the distribution of filtration-capacitance and geomechanical properties of the formation, hydraulic fracture design, leakage of fracturing fluid into the formation, fracture interference of neighboring wells. The method is realized in a hydrodynamic simulator and tested on actual data from wells drilled in a low-permeability reservoir.

Materials and methods
To solve the problem, the paper proposes:
    using a neural network to select the hydraulic fracture initiation interval;
    calculation of geometry and distribution of properties of each fracture in the hydraulic fracture simulator;
    equalizing of leakage distribution in hydrodynamic simulator and fracture simulator;
    use of permeability reduction factor in the hydrodynamic simulator in the zones of fluid penetration.

Keywords
horizontal well, hydraulic fracturing, neural network, low-permeability reservoir, hydrodynamic modeling, geomechanical modeling

Review of the world experience of well operation mode limitation in the context of water and gas breakthrough control in sub-gas zones

Yalaev A.V., Islamov R.R., Muslimov B.Sh., Kulesh V.A.

DOI: 10.24412/2076-6785-2024-2-24-31

Abstract
When developing water-in-oil and gas-in-oil-water zones of oil rims, over time the production of non-target fluid in the form of water or gas begins to dominate the overall flow, which leads to lower cumulative oil production and necessitates limiting the operating modes of both production and injection wells.
Finding the optimal well operation mode is an important task to minimize the production of non-target fluid and, consequently, to achieve the highest oil recovery.

Materials and methods
The experience of application of various options of water and gas coning control is considered: restriction of well operation modes, including intermittent operation, as well as autonomous inflow control devices.

Keywords
ptimal well operation mode, coning prevention, critical oil flow rate, gas-oil ratio reduction methods, inflow control devices, oil rim

Methodological basis for Turonian deposits production wells optimal design, using integrated geological and technological modeling

Babak A.I., Sventsky S.Yu.

DOI: 10.24412/2076-6785-2024-1-48-52

Abstract
The article examines the problem of production wells stock parameters optimization, using integrated geological and technological modeling.
The methodology proposed allows to identify the most effective parameters of the Turonian deposits production well stock, taking into account
the filtration-capacity properties of the deposit areas.

Materials and methods
Using filtration modeling to solve optimization problems.

Keywords
integrated modeling, gas deposit, hard-to-recover reserves, well productivity

Digital modernization of oil and gas production: tools and development indicators

Dmitrievsky A.N., Eremin N.A., Chernikov A.D.

DOI: 10.24412/2076-6785-2024-1-44-47

Abstract
Digital modernization of oil and gas production makes it possible to increase intellectual capabilities not only based on the data that is in the control system, but also on the basis of all available information, i.e. both historically accumulated and predictive, and contextual, which is not initially contained in the system and is formed based on analysis from various sources. A digital oil and gas field is becoming a production object with elements of artificial intelligence based on the integration of data, machine algorithms and robotic control systems, providing remote control, managing objects and processes, developing various control models and making criterion-based decisions. The challenges in the oil and gas sector in the context of sanctions pressure and decarbonization are global in nature; they can only be answered by relying on innovative oil and gas technologies, such as: digitalization of wells and fields, opticalization of the collection and transmission of large geodata, robotization of jobs, quantization, protection of geofield information and automation tools, intellectualization of decision-making in conditions of large geodata and the availability of a decision support system.

Materials and methods
The basis for the development of digital modernization of oil and gas production is the scientific and technical innovations of the digitalization programs of vertically integrated oil companies, which are ensured by supporting fundamental and applied scientific research and stimulating promising advanced development technologies. The transition from export-raw materials to resource-innovative development is the first stage in the implementation of the strategy for innovative development of the Russian economy. It is relevant to create a fundamental and multi-sensory instrumental basis for digital, innovative, energy-efficient, resource-saving, environmentally friendly technologies (digital wells and fields), ensuring the scientific and technical modernization of the countrys oil and gas industry in the context of sanctions pressure and reducing the carbon footprint.

Keywords
digital economy, digitalization programs of vertically integrated oil companies, digital field, digital well

Variative approach to the killing fluids selection for sandstone formations. Part 2. ore testing of killing fluids influence on rock permability

Shaydullin V.A., , Khatmullin A.R., , Turiyanov A.R., , Mingalishev F.K.

DOI: 10.24412/2076-6785-2024-1-38-42

Abstract
This study focuses on investigating the impact of water-based killing fluids on the reservoir permeability of oil-bearing sandstone formations in the Volga-Ural oil and gas province. The main factors influencing the effectiveness of killing fluids are the compatibility with formation brines and its effect on rock wettability. Field trials confirmed the relevance of the research, demonstrating a lower productivity loss, as well as a reduction in well shut-in time.

Materials and methods
The evaluation of the water-based killing fluids impact on the reservoir permeability was performed through core tests. Core samples was selected from Carboniferous and Devonian target intervals. Verification of the research results was carried out by testing the selected killing fluids during well workovers.

Keywords
killing fluid, core-flooding experiment, sandstone formation, scaling, salt precipitation, clay stabilizer, surfactant

Approbation of multiphase flow models for calculating pressure in the gas condensate wellbore in the RN-VEGA software. Part 2

Chiglintseva A.S., Zakharzhevsky Yu.A., Ibatulin A.A., Yamalov I.R.

DOI: 10.24412/2076-6785-2024-1-30-36

Abstract
In this paper presents the results of calculating pressure using such models of multiphase flow in a gas-condensate wellbore as Gray, No Slip and Beggs-Brill. Algorithms for calculating the properties of condensate and reservoir gas without / taking into account phase transitions are described. Comparison of the results of numerical pressure calculations based on models performed in the RN-VEGA software package with their analogues in the Saphir software module of the Ecrin from Kappa Eng., showed best convergence (the relative difference is not more than 0,5 %). A matrix of applicability of models that best predict pressure depending on the values of water-gas and condensate-gas factors according to field data has been obtained.

Materials and methods
In this work, the boundari es of the values of the water-gas and condensate-gas factors will be determined, at which the pressure along the gas-condensate wellbore is calculated using multiphase flow models with a permissible deviation based on field data.

Keywords
gas well, multiphase flow models, water-gas factor, condensate-gas factor

Simulation of a sucker rods string rotation during operation in curved and directional wells

Isaev A.A.

DOI: 10.24412/2076-6785-2023-5-78-83

Abstract
The paper considers a model of a sucker rod string in a curved two-branch wellbore. The effect of dogleg severity on rod breakage has been determined. The values of natural oscillation frequencies and resonant frequency of the system as a function of geometric shapes and dimensions of a curved section have been obtained in the course of the research. The mass of the eccentric disk significantly affects the angular speed. The bench tests have proved the restoring force on centralizer strips, as well as the values of loads on the strips depending on the movement of the outer pipe when the centering degree is reached. Conclusions and recommendations on application of new centering devices have been presented.

Materials and methods
Materials: progressive cavity pumping unit, eccentric disk, wellbore, centralizer with a bearing functions, vertical test bench with electric motor and frequency converter, horizontal test bench SITs-2 with a pipe simulator, vertical test bench SITs-2 for spring centralizers.
Methods: simulation, mathematical model of rod rotation deviating from the axis, determination of the frequency of natural torsional oscillations of rods and resonant oscillations.

Keywords
progressive cavity pump, directional wellbore profile, sucker rod string, reduced disc, moment of inertia, rigidity, number of revolutions

New approaches to the use of horizontal wells under flooding

Trofimchuk A.S., Khabibullin G.I., Ikhsanov D.R.

DOI: 10.24412/2076-6785-2023-5-74-77

Abstract
In recent years, there has been a trend of mass introduction and an increase in the share of horizontal wells including injection wells, mainly in conditions of hard-to-recover reserves. The paper compares the coefficients of horizontal wells pick-up and compares them with directional wells, in order to determine the area of their most effective application. For the first time in the practice of flooding with horizontal wells, the influence of such parameters as the length of horizontal wells, the number of stages and the loading of the proppant during hydraulic fracturing. Based on the results of the analysis, a new configuration of the development system is proposed.

Materials and methods
The data of the injectivity index of injection wells of more than 17 fields are analyzed, the correlation dependence of the multiplicity of the injectivity index on the permeability of the layers is constructed. The results of field geophysical studies were used: thermometry, noise measurement, flowmetry. Calculations were performed using a 3D hydrodynamic model in the PH-KIM simulator

Keywords
horizontal injection wells, waterflood-induced hydraulic fractures, hydraulic auto-fracture, low-permeability reservoirs, field development systems, reservoir pressure maintenance, hydrofracturing, increase recovery factor

The experience in intermittent production and de-gassed oil injection for dissipation of gas coning

Priz K.I., Alekseev A.S., Cherkasov N.A., Svyaschenko A.V., Ivanov E.N., Shilov D.S., Seksyaev A.P.

DOI: 10.24412/2076-6785-2023-5-69-73

Abstract
At present, in many major fields with a gas cap, there is a severe issue of gas breakthrough from the gas cap when thin oil rims are developed in infrastructure limitation conditions. One option to limit gas production, reduce GOR, and bring wells back into production, is intermittent operation of wells. To accelerate evening out of the gas cone and bringing wells back on line after intermittent production, re-injection
of de-gassed oil is applied. In the Srednebotuobinskoe Field located in East Siberia, pilot tests of de-gassed oil re-injection were conducted.
Based on the obtained effect, full scale application in the Botuobinsky Horizon commenced.

Materials and methods
In early 2022, the first treatment operations were implemented
in 14 wells. Based on the results, full scale application commenced.
The paper provides an analysis of de-gassed oil treatment operations and an assessment of the effect achieved with the technology.

Keywords
re-injection of de-gassed oil, coning, gas breakthrough, GOR, cumulative oil production, East Siberia, botuobinsky horizon