bluuebunny/crossref_metadata_2025 huggingface dataset:
Mediation and communication practices in education
Authors: Usmanova Elena , Khokhlova Elena , Fedoseev Roman
Published: October 2021

In the sphere of education, mediation and communication practices help not only to resolve disputes and conflicts most effectively but also to protect the interests of children and minors. The study aims to explore and analyze the effectiveness of mediation and communication practices in resolving conflicts in educational organizations, as well as identify trends in the development of this institution. The importance and role of using mediation and communication practices in conflict resolution in the sphere of education are analyzed and the theoretical aspects of the effectiveness of mediation in educational organizations are studied. The reasons for the emergence of conflicts in educational organizations are identified and the need to improve the effectiveness of mediation and communication practice implementation in conflict resolution in the sphere of education is substantiated. The study results allow outlining trends in the development of the studied institution. Further research can address the effectiveness of mediation and communication practices and the feasibility of using various methods and techniques to improve the use of mediation and communication skills in educational legal relations.
Tersine Göç Eğiliminin Akademik Diasporanın Verimliliği Üzerindeki Etkisi: Almanya Örneği
Authors: AKKUŞ Ömer , DURMAZ Atakan
Published: October 2021

Akademik diasporaların bilgi yaratım ve beşeri sermaye stoku artırım sürecinde hem bulundukları ülkelerde hem de anavatanları üzerinde etkileri söz konusudur. Bu çalışmada Türk Diasporasındaki akademisyenlerin tersine göç eğilimlerinin akademik verimlilikleri üzerindeki etkisi incelemektedir. Çalışmada, Almanya’daki üniversite ve araştırma merkezlerinde çalışan 466 Türk akademisyenden elde edilen veriler Probit Regresyon aracılığı ile analiz edilmiştir. Elde edilen sonuçlara göre, Diasporadaki bilim insanlarının fiziksel göç eğilimlerinin akademik verimlilikleri üzerinde anlamlı bir etkisi söz konusu değilken, fikirsel anlamda tersine göç eğilimi akademik verimliliği pozitif anlamda etkilemektedir. Buna göre diasporadaki bilim insanlarının fikirsel anlamda tersine göç eğilimi akademik verimliliklerini %0.12 oranında arttırmaktadır. Ayrıca akademik diasporanın uluslararası akademik bağlantılarının da akademik verimliliği pozitif etkilediği sonucuna ulaşılmaktadır.
An Evaluation Regarding the Duties of Concordat Commissioners in Concordat Process
Authors: TÜM Kayahan , ULUSAN Banu
Published: October 2021

Concordat, which had rare applicability in practice before amendments brought by Code Nr. 7101, is expected to maintain new maneuverability for debtors in financial difficulties while protecting the rights of creditors and establishing a more advantageous situation for them. In order to achieve these goals, a so to speak “conciliation” is ensured under supervision of court between debtors and creditors and thus both parties receive their rights and financial release at some point. While the process for this is ongoing, debtors are protected from possible legal pursuits and their transactions are supervised to prevent any damage to be done to creditors.

Commissioners have a great responsibility to secure these functions of the concordat. In this study, the concordat process is examined basing on phases of the process, and the duties of concordat commissioners are clarified depending on each phase. In this context, the legal background is explained while accounting information and financial aspects are taken into consideration.
Pengaruh Model Pembelajaran Team Assisted Individualization (TAI) Berbatuan Video Interaktif dalam Pembelajaran Jarak Jauh terhadap Kemampuan Pemecahan Masalah Matematis Siswa SMP Negeri 172 Jakarta
Authors: Marisa Fisabti Fadlilah  , Swida Purwanto  , Lukman El Hakim
Published: October 2021

Tujuan dilakukannya penelitian ini adalah untuk mengetahui apakah ada atau tidaknya pengaruh model pembelajaran Team Assisted Individualization berbantuan video interaktif dalam pembelajaran jarak jauh terhadap kemampuan pemecahan masalah matematis siswa. Metode eksperimen semu digunakan sebagai metode dalam penelitian ini. Populasi target pada penelitian ini adalah seluruh siswa SMPN 172 Jakarta, sedangkan populasi terjangkaunya adalah seluruh siswa kelas VIII. Cara pengambilan sampel menggunakan teknik purposive random sampling dan cluster random sampling. Instumen tes kemampuan pemecahan masalah matematis yang digunakan dalam penilitian ini berupa 4 butir soal uraian yang telah dinyatakan valid. Berdasarkan hasil prasyarat analisis data setelah perlakuan, kelas kontrol dan kelas eksperimen masing-masing homogen dan berdistribusi normal. Merujuk pada hal tersebut maka dilakukanlah uji t untuk pengujian hipotesis dengan taraf signifikansi α=0,05. Perolehan hasil perhitungan hipotesis statistik memberi kesimpulan bahwa rata-rata kemampuan pemecahan masalah matematis kelas eksperimen lebih tinggi daripada kelas kontrol. Hal tersebut menunjukkan bahwa terdapat pengaruh model pembelajaran TAI berbantuan video interaktif dalam pembelajaran jarak jauh terhadap kemampuan pemecahan masalah matematis siswa SMP Negeri 172 Jakarta. Besar pengaruh yang diberikan adalah 79% dan termasuk dalam kategori tinggi.
Pembelajaran Matematika Berbantuan Media Edmodo dalam Upaya Meningkatkan Kemampuan Pemecahan Masalah Matematika Siswa Kelas XI IPS 2 SMA Negeri 2 Tambun Selatan pada Materi Limit Fungsi Aljabar
Authors: Maulidina Farah Ayu , Sampoerno Pinta Deniyanti , El Hakim Lukman
Published: October 2021

Penelitian ini bertujuan untuk mengetahui keefektifan pembelajaran matematika dengan model e-learning menggunakan Edmodo dalam meningkatkan kemampuan pemecahan masalah matematika. Penelitian ini termasuk ke dalam penelitian tindakan kelas (PTK). Tindakan dilakukan dalam 3 siklus dengan total 10 pertemuan. Subjek dalam penelitian ini terdiri dari 6 orang siswa kelas XI IPS 2 SMAN 2 Tambun Selatan dari setiap kategori kemampuan pemecahan masalah. Instrumen yang digunakan dalam penelitian ini adalah observasi, wawancara dan tes kemampuan pemecahan masalah matematika. Analisis dilakukan secara deskriptif kualitatif dan kuantitatif. Hasil penelitian memperlihatkan bahwa terdapat peningkatan motivasi belajar dari keenam subjek penelitian sehingga pembelajaran matematika berbantuan Edmodo mampu meningkatkan kemampuan pemecahan masalah matematika siswa. Nilai rata-rata keenam subjek dan persentase ketuntasan belajar yang terus meningkat dari siklus I hingga siklus III dengan persentase tiap butir indikator pemecahan masalah dari siklus I hingga siklus III adalah sebagai berikut: (a) kemampuan memahami masalah meningkat dari 79,17% menjadi 88,89%, (b) kemampuan memilih strategi pemecahan masalah yang tepat meningkat dari 77,08% menjadi 97,22%, (c) menyelesaikan masalah dengan menerapkan strategi yang telah ditentukan meningkat dari 66,67% menjadi 86,11%, (d) verifikasi dan interpretasi hasil meningkat dari 66,67% menjadi 77,78%. Dapat disimpulkan bahwa pembelajaran menggunakan Edmodo efektif untuk meningkatkan kemampuan pemecahan masalah matematika siswa.
Severity of Inpatient Hospitalizations Among Undocumented Immigrants and Medi-Cal Patients in a Los Angeles, California, Hospital: 2019
Authors: Ro Annie , Yang Helen W. , Du Senxi , Hanlon Courtney L. , Young Andrew Shane
Published: October 2021

Objectives. To compare the severity of inpatient hospitalizations between undocumented immigrants and Medi-Cal patients in a large safety-net hospital in Los Angeles, California.

Methods. We conducted a retrospective analysis of all 2019 inpatient stays at a Los Angeles hospital (n = 22 480), including patients of all races/ethnicities. We examined 3 measures by using insurance status to approximate immigration status: illness severity, length of hospital stay, and repeat hospitalizations. We calculated group differences between undocumented and Medi-Cal patients by using inverse probability weighted regression adjustment separately for patients aged 18 to 64 years and those aged 65 years and older.

Results. Younger undocumented patients had less severe illness and shorter lengths of stay than their Medi-Cal counterparts. Older undocumented immigrants also had less severe illness, but had similar lengths of stay and were more likely to have repeated hospitalizations.

Conclusions. While existing work suggests that undocumented immigrants could have more severe health care needs on account of their poorer access to medical care, we did not see clear health disadvantages among hospitalized undocumented immigrants, especially younger patients. There were fewer differences between undocumented and Medi-Cal patients who were older. (Am J Public Health. 2021;111(11):2019–2026. https://doi.org/10.2105/AJPH.2021.306485 )
Electromagnetic Induction Heating for Bitumen Recovery: A Case Study in Athabasca Oil Sands
Authors: Sherwali Ahmed , Noroozi Mehdi , Dunford William G.
Published: October 2021

This paper demonstrates how electromagnetic induction heating is used for bitumen recovery from the Athabasca oil sands in Alberta with minimal external water requirements. The paper addresses the setup requirements and the necessary parameters for this method to achieve an economic energy to oil ratio.

An iterative process is followed to couple the heat rate generated by electromagnetic induction heating to the reservoir model over a defined period. The reservoir model represents a 33 meter payzone with properties for the lower McMurray formation in an area north of Fort McMurray within the Athabasca oil sands deposit. Several scenarios are extensively explored to reach the most practical and feasible setup for oil recovery. The process enables operators to monitor and control reservoir pressure and temperature, liquid production, and energy to oil ratio to maximize recovery from oil sands and heavy oil reservoirs.

The results show an expected ultimate oil recovery factor of +70% with an average energy to oil ratio that is lower than the average ratio associated with steam assisted gravity drainage. It is observed that the amount of energy required by the process correlates with water saturation in the near wellbore region, higher water saturation levels are preferred for enhanced oil recovery. It is also noticed that majority of the electromagnetically induced heat rate is generated in the near wellbore region vaporizing any existing water in that region, which eventually slows down the heating process. However, water injection improves the heat convection further into the reservoir, and therefore is essential for establishing a steam chamber using this method. Nevertheless, the volume of injected water required to establish a steam chamber is comparable to the overall volume of water produced from the reservoir, and thus minimal external water is necessary in this process. Moreover, the method is emissions free because heat is generated in the reservoir using an electrically powered downhole inductor (patent pending) that transfers electromagnetic energy to heat. In conclusion, this novel method shows high potential for responsible oil recovery from oil sands and heavy oil reservoirs while meeting economic and environmental expectations. This paper presents the use of a novel clean energy technology to recover bitumen from the Athabasca oil sands in Alberta. Furthermore, the technology is of high value to oil production from heavy oil reservoirs around the world and therefore provides large benefits to the energy industry.
Delineating the Multi-Stacked Domanik Play in the Volga-Urals Basin, Russia
Authors: Shaw Kevin , Randolph Theodore , Anthony William , Harkrider John D. , Gendelman Igor
Published: October 2021

This paper shows the importance of an integrated, multidisciplinary approach to exploiting the unconventional Domanik Play in the Volga-Urals Basin in Russia. A combination of understanding the reservoir and applying different completion techniques is necessary to verify the best way to drill, complete, and produce the basin.

In 2012, DirectNeft drilled the first well specifically targeting the Domanik interval in the Volga Ural Basin. This discovery well tested oil from multiple horizons within the 350+ m (1150’) thick "Domanikoid" section. In the broad Upper Frasnian interval, Well A was the first successful hydraulic fracture treatment in the Domanik. The subsequent Well B, seven miles to the northwest, penetrated a largely identical Domanik section and was also fractured and tested in multiple horizons, including the Upper Frasnian. Well tests, logs and core analysis have identified two primary and two secondary productive intervals within the Domanik.

These two wells provided the first sets of modern logs in the area, which are critical to better understand the reservoirs. In addition, the coring of key intervals and extensive analysis of those cores have proven invaluable in understanding the nature of the reservoirs. Existing well control and seismic data clearly indicate the thick section of Domanik rocks extends throughout the area. The presence and viability of oil saturated Domanik low permeability reservoirs has been confirmed by the two wells. Oil flows have been recovered from perforated intervals of the Tournaisian, Zavolzhian, Famennian and Upper Frasnian.

Based on these exploration findings, subsequent operations expanded the project by drilling four horizontal wells in 2017-2018, three of which have been completed. Objectives are multi-fold and included further delineation of the four productive intervals by refining the understanding of geologic, petrophysical and geomechanical models that influence the completion and stimulation operations, ultimately impacting production. Early results from the completed wells have shown a rapid improvement in production results, showing that the multidisciplinary workflow is successful. Future tests incorporate significant increase of entry points to further prove the success of the play.

This paper describes the methodology and modifications implemented based on improved understanding of the reservoir, including the use of multi-stage completion techniques. Also discussed are operational issues related to implementing state-of-the-art completion techniques including sliding sleeves, coil-tubing operations, jet cutting operations and plug and perf operations.
Technical Analysis of Sand Production for Offshore Natural Gas Hydrate Trials in South China Sea
Authors: An Kun , Lau Lawrence Khin Leong , Li Jian , Liu Jia
Published: October 2021

Natural gas hydrate emerges as a sustainable and alternative clean energy source. Japan (2013) and China (2017) have performed production trials on marine natural gas hydrate successfully. Sand production with associated risk is one of the main challenges for offshore natural gas hydrate production trials in Japan and China. Technical assessment related to sand production, transport and erosion is a crucial part for overall sand management strategy.

This paper demonstrates the importance of flow assurance for marine natural gas hydrate production through the analysis of sand management in South China Sea ShenHu area. Multiphase modelling tool is used to investigate sand transport phenomenon, with parametric study focuses on the effects of production rates, particle bed height and sand particle size. Detailed analysis of particle flow and related erosion along production flow path is investigated by developing a 3-dimensional Computational Fluids Dynamics (CFD) model.

Based on the matrix of sensitivity study, steady state operational map for continuous marine natural gas hydrate production is proposed. Such operational map provides useful risks level ranking based on actual field parameters including gas production rate, sand loading and particle size. The operator can maintain production at a lower risk based on the operational map.

Through detailed technical analysis of sand production and transport, risks associated with sand blockage and erosion can be actively managed. This provides high values in terms of operational safety, asset integrity, and full compliance with related national or international HSSE standards.
From Completion Design to Efficiency Analysis of Inflow Control Device: Comprehensive Approach for AICD Implementation for Thin Oil Rim Field Development Efficiency Improvement
Authors: Solovyev Timur , Mikhaylov Nikolay
Published: October 2021

The complex interbedded heterogeneous reservoirs of the Severo-Komsomolskoye field are developed by horizontal wells in which, as part of the pilot project's scope, autonomous inflow control devices (AICD) are installed to prevent early coning and gas breakthroughs in long horizontal sections and reduce sand production, which is a problem aggravated by an extremely low mechanical strength of the terrigenous deposits occurring in the Pokur formation of the Cenomanian stage in this area.

The zones produced through AICDs are separated by swell packers. The issue of AICD effectiveness is discussed in the publications by Solovyev (2019), Shestov (2015), Byakov (2019) and some others.

One of the methods used for monitoring horizontal sections with AICDs is production logging (PLT). However, due to the complexity of logging objectives, the use of conventional logging techniques makes the PLT unfeasible, considering the costs of preparing and carrying out the downhole operations.

This paper provides some case studies of the Through-Barrier Diagnostics application, including passive spectral acoustics (spectral acoustic logging) and thermohydrodynamic modelling for the purpose of effective estimation of reservoir flows behind the liner with AICDs installed and well integrity diagnostics.

As a result of the performed diagnostics, the well completion strategy was updated and optimised according to the log interpretation results, and one well intervention involving a cement squeeze with a straddle-packer assembly was carried out.
Dynamic Modeling of the Gas Discharge of a Mine in the Karaganda Coal Basin Under High Uncertainty Using a Multiple Realization Approach
Authors: Bigeldiyev Asfandiyar , Batu Assem , Berdibekov Aidynbek , Kovyazin Dmitry , Sidorov Dmitry , Temirkhassov Aidos , Zhumagulov Almas , Narimanov Yernar
Published: October 2021

The current work is intended to show the application of a multiple realization approach to produce a strategic development plan for one of the mines in Karaganda coal basin. The presented workflow suggests using a comprehensive reservoir simulator for a history matching process of a coal pillars on a detailed 3D grid and application of sensitivity and uncertainty analyses to produce probabilistic forecast.

The suggested workflow significantly differs from the standard approaches previously implemented in the Karaganda Basin. First, a dynamic model has been constructed based on integrated algorithm of petrophysical interpretation and full cycle of geological modeling. Secondly, for the first time in the region, dynamic modeling has been performed via a combination of history matching to the observed degassing data and multiple realization uncertainty analysis. Thirdly, the described model parameters with defined range of uncertainty has been incorporated into the forecasting of degassing efficiency in the mine using different well completion technology.

From the hydrodynamic modeling point of view, the coal seam gas (CSG) reservoir is presented as a dual porosity medium: a coal matrix containing adsorbed gas and a network of natural fractures (cleats), which are initially saturated with water. This approach has allowed the proper description of dynamic processes occurring in CSG reservoirs. The gas production from a coal is subject to gas diffusion in coal micropores, the degree of fracture intensity and fracture permeability. By tuning these parameters within reasonable ranges, we have been able to history match our model to the observed data. Moreover, application of an uncertainty analysis has resulted in a range of output parameters (P10, P50, and P90) that were historically observed.

Performed full cycle of CSG dynamic modelling including history matching, sensitivity, and uncertainty analyses has been performed to create a robust model with the predictive power. Based on the obtained results, different optimization technologies have been simulated for fast and efficient degassing through a multiple realization probabilistic approach. The coal reservoir presented in this work is characterized by very low effective permeability and final degassing efficiency depends on well-reservoir contact surface. The decrease of the well spacing led to a proportional increase of gas recovery which is very similar to unconventional reservoirs. Therefore, vertical and horizontal wells with hydraulic fractures have been concluded the most efficient way to develop coal seams with low effective permeability in a secondary medium.
Pilot Project Evaluating WAG Efficiency for Carbonate Reservoir in Eastern Siberia
Authors: Zharko Valentina , Burdakov Dmitriy
Published: October 2021

The paper presents the results of a pilot project implementing WAG injection at the oilfield with carbonate reservoir, characterized by low efficiency of traditional waterflooding. The objective of the pilot project was to evaluate the efficiency of this enhanced oil recovery method for conditions of the specific oil field.

For the initial introduction of WAG, an area of the reservoir with minimal potential risks has been identified. During the test injections of water and gas, production parameters were monitored, including the oil production rates of the reacting wells and the water and gas injection rates of injection wells, the change in the density and composition of the produced fluids. With first positive results, the pilot area of the reservoir was expanded. In accordance with the responses of the producing wells to the injection of displacing agents, the injection rates were adjusted, and the production intensified, with the aim of maximizing the effect of WAG. The results obtained in practice were reproduced in the simulation model sector in order to obtain a project curve characterizing an increase in oil recovery due to water-alternating gas injection.

Practical results obtained during pilot testing of the technology show that the injection of gas and water alternately can reduce the water cut of the reacting wells and increase overall oil production, providing more efficient displacement compared to traditional waterflooding. The use of WAG after the waterflooding provides an increase in oil recovery and a decrease in residual oil saturation. The water cut of the produced liquid decreased from 98% to 80%, an increase in oil production rate of 100 tons/day was obtained. The increase in the oil recovery factor is estimated at approximately 7.5% at gas injection of 1.5 hydrocarbon pore volumes. Based on the received results, the displacement characteristic was constructed. Methods for monitoring the effectiveness of WAG have been determined, and studies are planned to be carried out when designing a full-scale WAG project at the field.

This project is the first pilot project in Russia implementing WAG injection in a field with a carbonate reservoir. During the pilot project, the technical feasibility of implementing this EOR method was confirmed, as well as its efficiency in terms of increasing the oil recovery factor for the conditions of the carbonate reservoir of Eastern Siberia, characterized by high water cut and low values of oil displacement coefficients during waterflooding.
Evaluation of Residual Oil Saturation With Use of Single Well Chemical Tracer Test Swctt For Estimation of Eor Efficiency. From Theory to Experiment
Authors: Koryakin Fedor Andreevich , Tretyakov Nikolay Yuryevich , Vershinin Vladimir Evgenyevich , Ponomarev Roman Yuryevich
Published: October 2021

This article provides a brief overview of the theory of tracer studies, describes approaches to the interpretation of tracer studies using both analytical methods and hydrodynamic modeling, compares the results of analytical and numerical interpretation. The article also describes the problems that arise during the interpretation of real case study.
A 3-Step Reaction Model For Numerical Simulation of In-Situ Combustion
Authors: Rojas Allan A. , Yuan Chengdong , Emelianov Dmitrii A. , Saifullin Emil R. , Mehrabi-Kalajahi Seyedsaeed , Varfolomeev Mikhail A. , Sudakov Vladislav A. , Lotfullin Bulat R. , Shevchenko Denis V. , Ganiev Bulat G. , Lutfullin Azat A. , Zaripov Aza T.
Published: October 2021

In-situ combustion (ISC) is an effective thermal enhanced oil recovery method. However, it is still not widely implemented in oilfields. One of the factors limiting the wide application of ISC is the challenge in its simulation and prediction. In this work, the oxidation experiments of maltenes and asphaltenes in reservoir rock were performed in the porous media thermo-effect cell (PMTEC) to establish a simplified reaction model based on non-isothermal measurements and to use it in numerical simulation of ISC process. It was found that the oxidation reaction process of oil fractions can be divided into different regions depending on generated self-energy rate and oxygen consumption rates that is up to the temperature. In order to propagate reactions from one mode to another, a specific oxygen consumption per unit mass of oil fractions is required. The average oxygen requirement for crossing LTOad (low temperature oxidation, oxygen addition reactions) boundary into LTC (low temperature combustion) mode was 64 mgO2/g(maltenes) and 10.4 mgO2/g(asphaltenes). To propagate reactions into HTO mode from the LTC mode, it requires about 646 mgO2/g(asphaltenes) for asphaltenes fraction. Moreover, this characterization seems to be a key tool when designing air injection in field pilots. Additionally, it was revealed that asphaltenes are more exothermic and require lower oxygen uptake per unit of temperature increment in comparison to maltenes. Furthermore, the mass conversion data obtained from non-isothermal measurements of oil fractions allow for the estimation of the stoichiometry coefficients of two low temperature oxidation reactions, i.e. oxidation and cocking processes, which can be included into a numerical simulation model to replicate combustion tube (CT) results. The numerical simulation model reveals that the simplified reaction model from a 6-step into a 3-step reaction scheme can reproduce ignition process, temperature profiles, combustion velocity, and fluid production, which thus makes it suitable for the upscaled modelling of ISC.
Screening of Surfactants for Huff-N-Puff Injection into Unconventional Reservoirs
Authors: Scerbacova Alexandra , Ivanova Anastasia , Mukhina Elena , Ushakova Alexandra , Bondar Mikhail , Cheremisin Alexey
Published: October 2021

The gradual depletion of conventional oil reserves and the growing demand for hydrocarbon feedstock have led to shale deposits development necessity, which are characterized by high reservoir temperatures and very low permeabilites. One of the methods proposed for unconventional reservoirs development is surfactant injection in huff-n-puff mode. Unlike surfactant flooding, where the main effect is achieved through the displacement mechanism, the huff-n-puff method is based on capillary imbibition. Surfactant solutions decrease oil-water interfacial tension, change rock surface wettability to water-wet, lead to desorption of adsorbed hydrocarbons and increase relative permeability to water, thus increasing oil production.

A number of commercially available anionic and nonionic surfactants were selected for laboratory investigation. Compatibility with reservoir fluids and thermal stability were tested for 14 days. For the stable compositions, the interfacial tension at the boundary with oil was measured with the spinning drop method. Special attention was paid to the study of initial reservoir wettability and the ability of the selected surfactants to shift it towards water-wet. Wettability at the macro level was determined by the "sessile" drop method.

As a result of the screening, two surfactant compositions capable to alter the wettability of the rock surface to strictly water-wet were selected, as this is the key point when selecting surfactant compositions for low-permeable reservoirs. The optimum operating concentrations were selected to avoid the formation of a Winsor III microemulsion, which can lead to plugging of narrow channels and fluid flow blockage in the formation. Values of static adsorption onto crushed rock were also evaluated. The most effective composition was investigated in a huff-n-puff filtration experiment and positive results were obtained.

Nanoparticles were also screened as potential components of surfactant compositions. It was found that nanoparticles forming stable dispersions in surfactant solutions improve their ability to change the wettability to a water-wet state.

As a result of the laboratory work performed, it can be concluded that the huff-n-puff technology is applicable in unconventional reservoirs with very low permeabilities. The huff-n-puff mode for surfactant solutions injection is preferable due to lower surfactant consumption, targeted effect, and shortened well response time. Successful implementation of this technology on an industrial scale can improve the efficiency of shale oil production.
The Role of Emulsification and Interfacial Tension Ift For the Enhanced Oil Recovery Eor in Surfactant Flooding
Authors: Li Xiaoxiao , Yue Xiang'an , Zou Jirui , Zhang Lijuan , Tang Kang
Published: October 2021

In this study, a visualized physical model of artificial oil film was firstly designed to investigate the oil film displacement mechanisms. Numerous comparative experiments were conducted to explore the detachment mechanisms of oil film and oil recovery performances in different fluid mediums with flow rate. In addition, the of influencing factors of oil film were comprehensively evaluated, which mainly includes: flow rate, surfactant behaviors, and crude oil viscosity.

The results show that, (1) regardless of the viscosity of crude oil, flow rate presents a limited contribution to the detachment of oil film and the maximum of ultimate oil film displacement efficiency is only approximately 10%; (2) surfactant flooding has a synergistic effect on the oil film displacement on two aspects of interfacial tension (ITF) reduction and emulsifying capacity. Giving the most outstanding performance for two oil samples in all runs, IFT reduction of ultra-low value is not the only decisive factor affecting oil film displacement efficiency, but the emulsifying capability plays the key role to the detachment of oil film due to effect of emulsifying and dispersing on oil film; (3) the increasing flow rate of surfactant flooding is able to enhance the detachment of oil film but has an objective effect on the final oil film displacement efficiency; (4) flow rate have the much influence on the detachment of oil film, but the most easily controlled factor is the surfactant property. The finding provides basis for oil film detachment and surfactant selection EOR application.
The Use of a Sensor Modules System for Measuring Drilling Parameters in a Bit, Significantly Reduces the Construction Time of Wells in Eastern Siberia
Authors: Rebrikov Andrey Alexandrovich , Koschenkov Anton Anatolyevich , Rakina Anastasiya Gennadievna , Kortunov Igor Dmitrievich , Koshelev Nikita Vladimirovich , Dubrovskiy Maxim Petrovich , Bekasov Vladimir Olegovich , Yakimov Yuriy Anatolyevich , Grechikho Pavel Anatolyevich , Ataev Magomed Adamovich
Published: October 2021

Currently, production and exploration drilling has entered a stage of development where one of the highest priority goals is to reduce the time for well construction with new technologies and innovations. One of the key components in this aspect is the utilizing of the latest achievements in the design and manufacture of rock cutting tools – drill bits. This article presents some new ideas on methods for identifying different types of vibrations when drilling with PDC bits using a system of sensors installed directly into the bit itself.

In the oil and gas fields of Eastern Siberia, one of the main reasons for ineffective drilling with PDC bits are vibrations, which lead to premature wear of the cutting structure of the bit and the achievement of low ROPs in the dolomite and dolerite intervals. For efficient drilling of wells of various trajectories with a bottom hole assembly (BHA), including a downhole motor (PDM) and a PDC bit, special attention is paid to control of the bit by limiting the depth of cut, as well as the level of vibrations that occur during drilling process. Often, the existing complex of surface and BHA equipment fails to identify vibrations that occur directly on the bit, as well as to establish the true cause of their occurrence. Therefore, as an innovative solution to this problem, a system of sensors installed directly into the bit itself is proposed. The use of such a system makes it possible to determine the drilling parameters, differentiated depending on the lithological properties of rocks, leading to an increase in vibration impact. Together with the Operators, tests have been successfully carried out, which have proven the effectiveness of the application of this technology.

The data obtained during the field tests made it possible to determine the type and source of vibration very accurately during drilling. In turn, this made it possible to precisely adjust the drilling parameters according to the drilled rocks, to draw up a detailed road map of effective drilling in a specific interval. Correction of drilling parameters based on the analysis of data obtained from sensors installed in the bit made it possible to reduce the resulting wear of the PDC bit cutting structure and, if necessary, make changes to the bit design to improve the technical and economic indicators. Thus, the use of a system of sensors for measuring the drilling parameters in a bit ensured the dynamic stability of the entire BHA at the bottomhole when drilling in rocks of different hardness, significantly reduced the wear of the drilling tools and qualitatively improved the drilling performance.
7-inch Casing While Drilling CWD With Retrievable Bottom Hole Assembly BHA
Authors: Usmanov Askhat Radikovich , Shishkin Anton Mikhailovich , Merzlyakov Alexander Sergeevich , Karimov Jalal Lalash Ogli , Fedotov Anton Valeryevich , Khlebnikov Vladimir Ivanovich
Published: October 2021

Casing drilling technology, as an alternative to conventional drilling, has been known for a long time. This method is mainly used for wells with geological complications, such as lost circulation or wellbore instability of various nature. By using drilling on a string for a section or part of it, the problem interval is immediately cased, eliminating the time spent on additional operations, such as pulling the bottom hole assembly (BHA), wiper trips and running the casing. Thus, this allows to reduce the time for well construction, reduces the risk of accidents and non-productive time associated with the complication zone.

Casing drilling has become widely for drilling vertical surface conductors and technical casing with a drillable shoe, as well as for drilling with retrievable BHA in inclined sections for 324- and 245-mm casing.

The aim of this work was to perform directional drilling on a 178mm production casing in an interval where the client had geological problems associated with running casing due to a zone of rock collapse. The uniqueness of the task lies in the fact that no one in the world has yet performed drilling on a casing with a building inclination and landing into a horizontal plane. It was necessary to follow the designed well trajectory, to build inclination from 67 to 85 degrees with the planned dogleg severity of 1 degree / 10m.
Continuous Improvement: Rotary Steerable System with Electromagnetic Telemetry as Approach to Reduce Well Time
Authors: Rakhmangulov Farit , Dorokhin Pavel
Published: October 2021

One of the main challenges from operating companies is the continuous reduction of well construction time. During drilling, considerable time is spent on static measurements to determine the wellbore location and to verify that the actual well path matches the planned one. The electromagnetic telemetry system (EMT) allows the taking of static directional survey measurements during connections, when the drill string is in slips. Transmitting commands to the rotary steerable system (RSS) through the EMT does not cause the drilling process to stop, which also reduces well construction time.

The work describes well drilling experience with the use of the electromagnetic channel for communication with the rotary steerable system and the positive displacement downhole motor not only in horizontal section but in all well sections, starting from the top hole. Combined use of the complete logging while drilling tools (LWD) with this type of the telemetry system is a valuable finding. The article describes BHA, operational principles of this type of the telemetry system, and problems which may arise during operation.
Collaborative Approach Overcomes Cementing Challenges in Narrow Pressure Window Environment
Authors: Lobastov Denis , Nafikova Svetlana , Akhmetzianov Ilshat , Zaripov Shamil , Krivolapov Dmitry
Published: October 2021

The collaborative approach used for cementing the production liner in an onshore development well in Russia is presented. The reservoir has a narrow window between pore and fracture pressures, which has previously caused formation instability and severe lost circulation issues during well construction, compromising zonal isolation objectives.

Total loss of fluids experienced while cementing the 114.3 mm production liner in the first appraisal well in the field led to revising the cementing strategy. Collaboration among various parts of the drilling department and the opportunity to define a new approach resulted in a decision to introduce managed pressure drilling (MPD) to address the challenges associated with a narrow pressure window and uncertainty in pore pressure while drilling and cementing. This enabled implementing the optimal mud weight and adjusting equivalent circulating density (ECD) during cementing with minimum overbalance.

Reducing the mud weight from 1.20 SG to 1.05 SG eliminated losses after running the liner and while cementing it. As a result, pre-job circulation rates and pumping rates during cementing could be increased, improving mud removal efficiency and achieving top of cement at the required depth. The constant-bottomhole-pressure mode of MPD was used to maintain the same ECD during displacement of the well to a lighter fluid and during cementing, avoiding well influx during pumpoff events by compensating for the annular friction pressure loss with surface backpressure. This first onshore managed pressure cementing operation executed within the same field in Russia (later named as field A) was completed flawlessly, with no safety or quality issues, zero nonproductive time, and achievement of the required zonal isolation across the challenging production section.

The collaborative approach used was a novel strategy, with the mud weight program strategically adjusted before and during the cementing operation to achieve zonal isolation objectives.
Successful Application of Managed Pressure Drilling and Cementing in Naturally Fractured Carbonates Environment of Prohorovskoe Exploration Well
Authors: Krivolapov Dmitry , Soroka Taras , Polyarush Artem , Lobastov Denis , Balalaev Viktor , Valisevich Aleksey , Ivanov Pavel , Pozdnyakov Anton , Smolev Dmitry , Frankov Dmitry
Published: October 2021

This technical paper provides the result of utilizing MPD technology for drilling and cementing a 127 mm production liner withing the Zadonian horizon D3zd in an exploratory well of the Prohorovskoe field. The previous wells drilled with a conventional approach in the field had complicated issues such as circulation losses and well control. It was complexified with high hydrogen disulfide concentration in reservoir oil which was a health hazard to a site personnel. As a result, to eliminate all complications, resources and operational time were needed.

To prevent and eliminate complications in a long wall, core drilling and well completion, managed pressure drilling (MPD) and cementing technology with semi-automatic control system was applied. The project is unique as such complicated jobs with the core drilling and cementing with MPD were executed for the first time in The Komi Republic.

MPD approach allowed to figure out bottomhole safe conditions and maintain ECD within a required pressure window. It is necessary to notice that a part of the section was core drilled.

Knowing the window between pore and fracture pressures safety limits, a run-in-the-hole design with further cementing job was optimized. The execution was done flawlessly without circulation losses and well control issues.

In comparison to a previous well in the Prohorovskoe field, MPD allowed to shorten loss circulated mud volume from 2 2215 m3 to 0 m3 and avoid non-productive time.

Through accomplished goals and lessons learned, new grounds to well owners and well services in a field development stage are broken.
Application of the Advanced Methods to Investigate Incidents and Drilling Engineering Principles to Prevent Critical Wear-Out of Downhole Equipment When Drilling Wells in Chayandinskoye Field
Authors: Abaltusov Nikolay Valerevich , Ryabov Anton Sergeevich , Perunov Artem Evgenevich , Rublev Sergey Sergeevich , Mitrokhin Sergey Aleksandrovich , Mukhachev Igor Yurevich , Fomchenko Roman Gennadevich
Published: October 2021

The pressing challenge is the abnormally rapid wear of well logging equipment and drilling tools when drilling wells in pay zone of Chayandinskoye field. Wear-out of BHA stabilizers within one run makes directional drilling inefficient and results in additional trips to replace equipment. Wear-out of drill pipes results in emergencies risk increase. To prevent such incidents the necessity arises to conduct an unscheduled inspection, reject and replace drilling tools. All these conditions entail increase in drilling time and decline in profitability.

Problem analysis and expert review was made by drilling optimization specialists from DD Contractor jointly with the experts from R&D Center and Operator Company.

This paper discusses how cooperation of the engineers from three companies as well as a particular approach to incident investigation and drilling engineering made it possible to identify the most critical factors, which contribute to a standard BHA wear, to work out measures to prevent similar situations in future and select an alternative BHA.

The gained experience has been successfully disseminated to the other wells in Chayandinskoye field and other fields in Eastern Siberia; and the incident investigation methods and drilling engineering procedures are effectively applied under the other projects.
Specialized ESP Layouts for the Operation of Deep Wells Confined to the Category of Hard-to-Recover Reserves
Authors: Sarapulov Nikolai Pavlovich , Vasin Maxim Valerevich , Palandzhyants Andranik Sedrakovich , Tambovstev Evgeni Alexandrovich , Khabibullin Rinat Alfredovich
Published: October 2021

The article is devoted to the selection of a specialized configuration of submersible equipment to minimize downhole pressure in order to intensify the flow of fluid to the wells of Gazpromneft-Orenburg. The depth of the wells and the design features of the well do not allow sufficient depth of the pumping equipment (top of the perforation interval 3800-4200 m). In addition, the operation of the fund is complicated by abnormally low reservoir pressures (60-120 at), low filtration-capacity properties and high linear pressures of single-standing wells (20-30 at).

To increase the productivity of wells, the ESP layout was used with a two-way engine, two submersible pumps and a shank. The layout is chosen in such a way as to reduce the density of the liquid column under the pump due to the circulation of the liquid by the lower pump. A special feature of the design was the selection of the length and the limit of the descent of the shank, the ratio of performance and pressure of the upper and lower pumps and a number of pre-connected devices as part of the layout.

Pilot tests were conducted at three wells of the Gazpromneft-Orenburg field. After the installation and commissioning work in the process of bringing the wells to the established mode, the features of the ESP that differ from the standard operation, leading to an increase in the period of stable well production, were revealed. According to the results of the tests, an increase in the oil flow rate of an average of 16 tons per day was obtained. The study of the characteristics of a complete installation directly on the test wells allowed us to determine the technical capabilities of the equipment, the volume-flow characteristics of the fluid under the pump and PVT. The aspects of natural separation and free gas content at the inlet of both pumps are studied, which is also a boundary condition for well intensification.

The tests allowed us to assess the technological limit of the layout with two ESP in the conditions of the Gazpromneft-Orenburg field. In contrast to other options for the operation of hard-to-recover wells, the proposed layout has a number of advantages, such as a minimum increase in the cost of construction, simplicity of construction, which ensures high operating time of equipment and low specific energy consumption. Based on the results of testing the pilot installations, a decision was made to replicate this approach in the Company.