bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk Management Approach: Drilling and Completion Projects
Authors: Ruzhnikov Alexey , Yurtaev Viktor 
Published: October 2021

Abstract
This manuscript describes the approach in the risk management developed and implemented while operating 21 drilling rigs on 13 fields simultaneously in the Middle East, which resulted in 40% reduction of non-productive time. Well construction process requires a lot of attention on different levels and from different sides to ensure trouble-free execution. The bigger the volume of work, the higher the chance of a costly mistake.
The risk management process was split in several steps, where different levels and divisions are involved. The Planning stage starts at engineering level and associated risk review goes to a level of Division Supervisor for every well, when special tools were developed to focus on potential high impact events. The Execution stage was covered by a set of Critical Activity reviews and Standard operation procedures, focusing on operations with highest risks or highest benefits. Further at the Evaluation stage every well was analyzed following the developed workflow, and further all obtained knowledge shared with every team member via custom designed dashboards.
Shortly after initial steps were taken under the new risk management approach, one of main KPI – non-productive time (NPT) – started to decrease and dropped by 5% within one quarter. Further tuning of the process allowed to decrease NPT by over 40% with continuous positive trend. One of the main contributors is the re-focusing on the prevention measures during planning stage, which avoid non-conformance events with high impact. Simultaneously the approach unified the practices of different divisions and remove misalignment on most of the technical issues and questions. Additionally, it decreased the workload of the key field personnel, as reduced NPT gives more time to focus on continuous rig performance improvement.
Adaptation of Capillary String for the Surfactants Delivery into a Gas Condensate Well and Optimization of its Operation Using Dynamic Multiphase Flow Simulator
Authors: Solovev Daniil Yurievich , Epryntsev Anton Sergeevich , Eliseev Petr Ilich , Yamov Andrey Gennadievich , Nerodenko Yamov Grigorievich , Guseynov Elkin Bakirovich , Bobrov Vladimir Alexandrovich 
Published: October 2021

Abstract
The studied productive formation of gas condensate field is at the stage of declining production. The inflow of bottom water due to the rise of the GWC and the design features of horizontal wells (large tubing and liner diameters) create the prerequisites for the development of a liquid loading of wells. This necessitate the optimization of the existing method of liquid unloading by dosing surfactants into the annulus.
In order to increase the efficiency of well treatment with a foaming agent, the use of a surfactant injection system through a capillary string suspended inside a tubing is considered. The use of this system allows to increase the speed and depth of surfactant delivery, use the potential of the well by simultaneous work in tubing and annulus during significant watering period (water flow rate: 50 and more m3 / day), reduce reagent losses associated with retention on the casing walls, and reduce the required consumption of surfactant.
The capillary string for the pumping surfactant is applicated to ensuring the stable operation of gas condensate wells during liquid loading. But today there are not ready-made applied solutions for correctly accounting surfactant action in unsteady flows conditions in the well.
The paper presents the substantiation and analysis of the capillary string introduction into the well for the pumping surfactant using specialized software. In the course of work, the main analysis tool is the dynamic modeling of multiphase flows in the conditions of steady and unsteady processes in wells. This approach use is aimed at determining the optimal depth and diameter of capillary, the required consumption and concentration of surfactant, the rate of its delivery to the bottomhole, and the liquid removal efficiency from the horizontal wellbore.
Method for Determine Optimal Parameters of Gas Field Development System
Authors: Apasov Renat Timergaleevich , Perevozkin Igor Vladimirovich , Badgutdinov Ruslan Rustamovich , Bazhenov Dmitriy Yurievich , Nekhaev Sergey Aleksandrovich , Varavva Artem Igorevich , Koryakin Fedor Andreevich , Samolovov Dmitriy Alekseevich , Sandalova Ekaterina Evgenievna , Yamaletdinov Ayrat Flyurovich 
Published: October 2021

Abstract
The request for optimization of development system parameters, well designs and the ground facility architecture is permanent task during the development of hydrocarbon fields. Decrease in the quality of oil and gas reserves, development of fields in difficult environment conditions and in the Arctic, oil and gas prices development lead to an increase in the sensitivity of new field’s development profitability from the parameters of the development system and field facilities.
Infrastructure of a field for the development of a gas field is associated with significant capital costs, both for the construction of wells and local infrastructure facilities, and for the construction of facilities for the preparation and transportation of gas. Therefore, one of the main tasks in the design of gas field development is the calculation of the optimal parameters of the development system - the number of wells and gas production plateau. Now the most well-known approaches to solving this problem are the calculation of different development variants using integrated numerical hydrodynamic models (Apasov et.al., 2018), taking into account all the features of the field under consideration or using analytical models based on the fundamental principles of filtration theory and development experience.
In such conditions, when solving optimization problems, it is necessary to take into account all the components of the production system (Khasanov et.al., 2020), otherwise it can be an incorrectly assessment of the economic effect of optimization and face the unprofitability of the developed design solutions. For most oil fields, the interinfluence of the reservoir part of the field, well lifts and the infrastructure is relatively weak, therefore, these parts can be optimized separately. When designing the development of fields with oil rims and gas fields, especially multilayer ones, optimization requires searching for a global optimal solution, investigating the existence and uniqueness of such a solution - on the models describing the field and interaction of the infrastructure, well lifts and the reservior part.
Forecasting the Water Flooding for the Production Wells of a Gas Condensate Field with a Fractured Reservoir Type
Authors: Gladkov Pavel Dmitrievich , Zheltikova Anastasiia Vladimirovna 
Published: October 2021

Abstract
As is known, fractured reservoirs compared to conventional reservoirs have such features as complex pore volume structure, high heterogeneity of the porosity and permeability properties etc. Apart from this, the productivity of a specific well is defined above all by the number of natural fractures penetrated by the wellbore and their properties. Development of fractured reservoirs is associated with a number of issues, one of which is related to uneven and accelerated water flooding due to water breakthrough through fractures to the wellbores, for this reason it becomes difficult to forecast the well performance.
Under conditions of lack of information on the reservoir structure and aquifer activity, the 3D digital models of the field generated using the hydrodynamic simulators may feature insufficient predictive capability. However, forecasting of breakthroughs is important in terms of generating reliable HC and water production profiles and decision-making on reservoir management and field facilities for produced water treatment. Identification of possible sources of water flooding and planning of individual parameters of production well operation for the purpose of extending the water-free operation period play significant role in the development of these reservoirs.
The purpose of this study is to describe the results of the hydrochemical monitoring to forecast the water flooding of the wells that penetrated a fractured reservoir on the example of a gas condensate field in Bolivia. The study contains data on the field development status and associated difficulties and uncertainties. The initial data were results of monthly analyses of the produced water and the water-gas ratio dynamics that were analyzed and compared to the data on the analogue fields. The data analysis demonstrated that first signs of water flooding for the wells of the field under study may be diagnosed through the monitoring of the produced water mineralization - the water-gas ratio (WGR) increase is preceded by the mineralization increase that may be observed approximately a month earlier. However, the data on the analogue fields shows that this period may be longer – from few months to two years.
Thus, the hydrochemical method within integrated monitoring of development of a field with a fractured reservoir could be one of the efficient methods to timely adjust the well operation parameters and may extend the water-free period of its operation.
Efficiency Survey of a Drainage Wellbore and Well Placement in Gas Fields
Authors: Penigin Artem Vitalevich , Sergeev Evgeniy Ivanovich , Varavva Artem Igorevich , Yamaletdinov Airat Flurovich 
Published: October 2021

Abstract
The paper describes the assessment process of methods for the construction and operation of gas wells with a large water-gas ratio. One of the ways to tackle the issue of poor performance of high WGR wells is to drill a drainage wellbore with an ESP to lift accumulating water. In addition, various configurations of well placement through gas-bearing and water-bearing reservoirs have been considered.
To evaluate the efficiency of a drainage wellbore with an ESP installed for lifting water that comes from the main, productive, wellbore, industry-recognized non-stationary dynamic multiphase flow simulator was used, as well as a more refined tool, such as the physical simulator based on the finite volume method (computational fluid dynamics, CFD). A non-stationary dynamic simulator was also used to assess the impact of well placement through gas- and water-bearings reservoirs. Well data, fluid data, physical parameters were entered into the models and, by varying the input parameters, dependencies and results were obtained, allowing to draw a conclusion about the efficiency of each method, as well as about the software capabilities and limitations.
The applicability and technical efficiency of an additional drainage borehole with an ESP tto ensure stable operation / high productivity of the well strongly depend on the value of the water-gas ratio, the higher it is, the lower the efficiency of the method. In addition, efficiency also decreases with increasing gas rate. To assess the correctness of the calculation made with dynamic multiphase flow simulator, which is the industry standard, a verification calculation was also carried out on a physical simulator using the finite volume method, which shows the same trends, but with different absolute values. It also made it possible to assess the influence of the geometry factor on the distribution of flows, which could not be done by the non-stationary multiphase flow simulator. Apart from this, it was concluded that the location of a water-bearing reservoir in the last lower part of the wellbore is preferable, since then the impact on production is less than when it is located above the gas-bearing interval. Changing the well layout to a U-shaped one affects the dynamics of its operation insignificantly.
The study helps to answer the question about the efficiency of using a borehole with an ESP and about the degree of influence of drilling through gas- and water-bearing reservoirs using the example of a real field, as well as it presents the method of conducting such an assessment for other fields.
Solving the Problem of Operational Accounting of Well Drilling Results in a Full-Scale Model of Unique Gas Condensate Fields
Authors: Poushev Andrey Viktorovich , Mangushev Ruslan Railievich , Yakimov Sergey Anatolievich 
Published: October 2021

Abstract
Today, strategic planning of field development is based on full-field static and flow simulation models which are regularly updated as part of field surveillance programs and by integrating the actual results of drilling and testing of new production and exploration wells and integrated interpretation of seismic surveys and reservoir core and fluid laboratory analyses.
One of the key factors for the success of investment projects is how quick and flexible the decision-making process is. Therefore, in modern conditions, prompt integration of new data into full-field flow simulation models followed by their processing, analysis, and decision-making on adjusting the strategic goals is of particular relevance for oil and gas production companies.
For unique multi-reservoir fields containing dozens of reservoirs, hundreds of accumulations and wells, it is hardly possible to promptly update full-field static and flow simulation models within less than 6-12 months, therefore, the decisions are made in the absence of up-to-date models, which may lead to poor quality of production forecasts.
The purpose of the study was to develop an approach to the modeling of unique fields, which would allow prompt integration of new data in a full-field flow simulation model while keeping the level of detail without significant time input.
Residual Hydrocarbon Saturation in the Transition Zone and the Gas Cap
Authors: Cheremisin Nikolai Alekseevich , Shulga Roman Sergeevich , Zagorovskiy Alexey Anatolyevich , Gilmanov Yan Irekovich , Kochetov Alexey Valentinovich 
Published: October 2021

Abstract
The laboratory study of the formation of residual oil saturation in a gas cap after active gas production from it and the penetration of oil from the underlying oil reservoir is currently not regulated in any way. Residual oil saturation in the gas cap was taken and is accepted, as a rule, from the correlation dependences with reservoir properties obtained from experiments on oil displacement from to the limit oil-saturated core samples. The use of similar correlations for the transition zone significantly underestimates the mobile oil reserves in such zones
In this connection, the paper discusses the technology of physical modeling of the residual oil saturation in the gas cap after the penetration of oil into it and the issues related to the determination of the residual oil saturation in the transition zones of oil reservoirs. On a series of test experiments on core samples of a weakly consolidated reservoir of the Pokurovskaya formation carried out according to the method developed by the authors, it was shown that the values of residual oil saturation after the penetration of oil into the gas cap are significantly lower than for oil-saturated formations with similar properties.
It is shown that such studies will make it possible to clarify the possible irreversible oil losses during the advanced development of gas caps and to revise the approaches to the development of oil reservoirs of gas-oil and oil-gas fields. Laboratory modeling and study of the process of oil penetration into a gas cap and its subsequent displacement by water or gas is relevant for almost 10% of Rosneft's current reserves.
Application of Digital Rock Analysis for Evaluation of Gas-Condensate Transport
Authors: Dinariev Oleg , Evseev Nikolay 
Published: October 2021

Abstract
The computational method for gas-condensate phase permeabilities is presented using digital rock analysis. The proposed method combines: a) construction of high-resolution tomographic images of the pore space; b) development of compositional model of a gas-condensate mixture at pore-scale including rheology, fluid-fluid and fluid-rock interfacial tension coefficients, and thermodynamic and kinetic properties of fluid phases; c) 3D pore-scale modeling of multiphase transport and interfacial chemical component exchange using the density functional hydrodynamics numerical simulator.
This digital rock analysis workflow is applied to the gas-condensate transport at pore-scale. The numerical simulations are carried out using the 3D digital rock model constructed by X-ray microCT imaging of the rock pore structure. By specifying different gas and condensate fractions and injection rates it has been possible to obtain computationally 3D saturation distribution fields and the phase permeabilities. The results of 3D density functional hydrodynamic simulations provide the comprehensive description of gas-condensate mixture at pore-scale including hydrodynamic desaturation effects and phase transition kinetic phenomena. It is demonstrated that condensate distribution in pores, phase mobility thresholds and phase permeabilities are dependent on wettability properties and flow rates. It is shown that condensate composition in individual pores is also dynamically dependent on flow regimes. These results can be used in field development planning for the improved evaluation of condensate banking in the vicinity of production wells and condensate losses in the reservoir.
Application of High-Contrast µCT and FIB-SEM for the Improvement in the Permeability Prediction of Tight Rock Samples
Authors: Avdonin Alexander , Ebadi Mohammad , Krutko Vladislav 
Published: October 2021

Abstract
Digital rock analysis has proven to be useful for the prediction of petrophysical properties of conventional reservoirs, where the pore space is captured well by a modern µCT scanner with a resolution of 1-5 µm. Nevertheless, this resolution is not enough to accurately capture the pore space of tight (low-permeable) rock samples. As a result, derived digital rock models do not reflect the real rock topology, and permeability predictions yield unreliable results. Our approach deploys high-contrast µCT scanning technique and Focused Ion Beam milling combined with Scanning Electron Microscopy to improve the quality of digital rock models and, hence, the permeability prediction. This workflow is successfully applied to a low-permeable rock sample of Achimov deposits. The computed permeability compares well to the experimental value.
Environmental Monitoring and Control Over Production Wells Using Automated Control and Regulation Systems for Orenburgskoe Oil and Gas Field
Authors: Rogov Yuri , Rymarenko Konstantin , Mironositskii Alexei , Grishenko Sergey , Golubtsov Alexsandr , Kabanov Vasilii , Gusachenko Tatyana , Nukhaev Marat 
Published: October 2021

Abstract
Environmental stability and safety are becoming increasingly important in the world. Used to be mainly until recently under state control, the release and distribution of hazardous substances, wastes, and by-products is now monitored and regulated everywhere by enterprises, forced to establish special services that record and transmit information in the dispatch centers of the MES and other regulatory authorities of the Russian Federation. All the measures taken in this respect focus on safety improvement, ensuring occupational safety and accident prevention at enterprises, and safety of people, animals, and natural environmental location, which can be exposed to harmful and dangerous anthropogenic and natural factors.
Aiming to provide a comprehensive solution to the problem, the authors proposed the concept of environmental monitoring and control over oil and gas wells using automated control and regulation systems and presented the concept on the example of the Orenburgskoe oil and gas condensate field
3D Modeling of Stability of Mobile Jack-Up Rigs Under Seismic Impacts
Authors: Vasilev Ivan Alekseevich , Dubinya Nikita Vladislavovich , Nachev Viktor Andreevich , Alekseev Dmitry Aleksandrovich , Tikhotskiy Sergey Andreevich 
Published: October 2021

Abstract
The work is devoted to the study of the influence of external mechanical impacts on the stability of jack-up floating drilling rigs. Ensuring safety when working on jack-up floating drilling rigs (jack-up rigs) is one of the most important tasks at the initial stages of offshore hydrocarbon field development. The aim of the work is simulation of the stability of the rigs, which is in the operating mode, both in the absence of external effects acting on it, and when it is affected by various geodynamic processes. Calculation of jack-up rig stability in sea soil with complex viscoelastoplastic rheology under external mechanical influences was carried out using the finite element method. As a result of the work, the spatial distributions of stress and strain fields were determined both in the jack-up rig itself and in the area of the soil in the vicinity of its supports, in an equilibrium and disturbed state. The results of equilibrium static calculations made it possible to analyze the zones of localization of stresses and deformations in the jack-up rig with respect to stability: the structural elements that are most dangerous from the perspective of stability loss were identified. The analysis of the soil area in the vicinity of the jack-up rig supports made it possible to estimate the typical dimensions of the stress concentration zones arising during the jack-up installation and draw conclusions about the requirements on details and scalability of the model of mechanical properties needed for geomechanical modeling at specific objects. The obtained results of dynamic calculations - the response of theconsidered system to external influences simulating remote seismic processes - made it possible to study the process of loss of jack-up rig stability. The critical values of the parameters describing external influences were determined: in particular, the amplitudes of surface seismic waves leading to the loss of stability of the jack-up rig were found. The obtained results made it possible to formulate an algorithm for predicting seismic hazard during drilling in offshore conditions, based on numerical modeling of mechanical processes at specific locations.