bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure and Tribological Properties of Chromium Coatings Formed by Electrodeformation Cladding with Flexible Tools
Authors: Sheleg V. K. , Levantsevich M. A. , Pilipchuk Y. V. , Nazarov S. M.
Published: October 2019

The paper contains results of investigations on structure and tribotechnical properties of chromium coatings formed by a method of electrodeformation cladding with flexible tools (EDCFT). The purpose of these investigations is to assess prospects for application of the coatings as an alternative to galvanic chrome plating which is widely used in manufacturing hydraulic cylinder rods of metal-cutting machines. Rotary metal brushes with a wire pile made of 65Г-steel and 03Х17Н14М2-stainless steel have been used as a flexible tool. A compacted bar obtained by sintering a mixture of pure chromium powders and a nano-sized diamond-graphite blend UDDG has been employed as a donor material for EDCFT. According to results of the research it has been established that alloying elements of wire pile such as chromium and nickel are added to a coating composition while forming coatings a stainless steel brush. So in the case of using brushes with wire pile of 03X17H14M2-stainless steel the amount of chromium and nickel in a clad coating layer is 5.3 and 9.6 times higher in percentage, respectively, in comparison with the coating formed by a 65Г-steel brush that can contribute to improvement of coating corrosion resistance. At the same time, surface relief of the coating has a developed rough structure consisting of chromium microparticles having various size that are tightly packed and elongated in the direction of brush rotation and there are no flaws in the form of discontinuities and delaminations. Tribological tests have been performed under conditions of “boundary lubrication” on a rotary friction machine that implements friction of a rubber indenter on a flat surface of a rotating disk. According to data of the tribotechnical tests it has been ascertained that under conditions of “boundary friction” for such paired samples as “coated disc – rubber roller” chromium coatings formed by the EDCFT method, have the lowest values of a sliding friction coefficient (fтр = 0.023) which are 7.5 times lower than chromium coatings obtained by electroplating. At the same time the wear of rubber rollers in pairs with electroplated chromium coatings has turned out to be less than in pairs with the coating formed by the EDCFT method.
Improving Properties of Tool Steels by Method of Dynamic Alloying
Authors: Kalinichenko A. S. , Ovchinnikov V. I. , Usherenko S. M. , Yazdani-Cherati Javad F.
Published: October 2019

The influence of high-speed particle fluxes on changes in the structure and properties of materials has been widely studied currently. The effect exerted by particles moving at very high speeds can have both negative (in spacecrafts) and positive character (dynamic processing of tool steels). Therefore a task for studying an effect of high-speed particle flows on structure change in tool steels and improving their performance properties has been set in the paper. The study has used an explosive method for creation of a high-speed flow of SiC + Ni and Al2O3 particles. Samples after dynamic alloying have been subjected to diffusion nitriding. Microstructure of specimens made of X12M, R18, R6M5K5steel has been studied using optical and electron metallography. Wear resistance of the samples has been also tested on a friction machine. Theoretical and experimental results on a complex effect of high-speed microparticle flows and nitriding on a structure and properties of tool steels have been obtained during the research. It has been established that dynamic alloying by particles leads to formation of a specific structure in a composite material reinforced with channels. Central fiber (channel) zone with powder particles residues is surrounded by areas of amorphous state which is succeeded by a zone with a nanocrystalline fragmented cellular structure. Then we observe a zone with a microcrystalline structure that transits to a zone with crystalline structure which is characteristic for a matrix material of structural steel. The obtained data can expand and complement some ideas about mechanisms for dynamic loading of solids and condensed matter, plastic deformation, physical mechanics of structurally inhomogeneous media at different levels, a number of effects arising from collision and ultra-deep penetration of microparticles into metals. It has been shown that wear resistance of high-speed steel subjected to dynamic alloying in the quenched state is increased by 1.2 times in comparison with wear resistance of steel alloyed in the annealing state.
Electrochemical Cutting of Micro-Holes in Tubular Stepped Concentrator-Waveguide for Medical Purposes
Authors: Aliakseyeu Yu. G. , Korolyov A. Yu. , Budnitskiy A. S. , Wenqi Dai
Published: October 2019

A great attention has been recently paid to development of ultrasound technologies for treatment of blood vessels throughout the world. Authors of the paper have developed a new effective treatment method and ultrasound equipment that allow to carry out destruction of intravascular formations with simultaneous increase in elasticity of a vascular wall together with cardiologists from Belarusian Medical Academy of Postgraduate Education and Republican Scientific and Practical Center “Cardiology”. Advantages of the method are absence of necessity in surgical intervention, low probability of complications, low cost of treatment. The main component of the developed ultrasonic equipment is a tube-type stepped concentrator-waveguide having a spherical tip at a distal end with a single axial hole of 0.5 mm-diameter and three radial holes of 0.3 mmdiameter located at an angle of 120° relative to each other. The main effect for application of the concentratorwaveguide is achieved by ultrasonic vibromechanical action of a spherical tip on intravascular formation with subsequent removal of destruction products by their aspiration from a vascular bed. An additional effect is provided due to cavitation action on vascular formation and vessel walls by flow of fluid supplied via an internal cavity of the stepped concentratorwaveguide through the holes in the spherical tip. This contributes to a significant improvement in elastic properties of a vascular wall in atherosclerosis and diabetes. It is necessary to ensure high accuracy and quality of surfaces for the formed microholes in order to achieve maximum efficiency of the cavitation jet impact on intravascular formations and on the vascular wall. According to the analysis results on specific features of existing methods for small-diameter hole shaping, an electrochemical hole cutting method has been proposed which allows to obtain accurate micro-holes with a diameter of 0.3 mm and high surface quality in parts of small cross section and rigidity. The paper presents results of study on effect of electrochemical holes cutting parameters (voltage, concentration and consumption of electrolyte) on size and shape of the formed microholes. Main modes of electrochemical holes cutting process have been developed which allow to form micro-holes in a spherical tip of a tubular concentrator-waveguide with required accuracy, dimensions and shape.
Influence of Diesel Fuel Ignition Portion Value on Working Process Parameters of Gas-Diesel Engine
Authors: Vershina G. A. , Bystrenkov O. S.
Published: October 2019

More and more requirements are imposed to engines of internal combustion due to the passage of time. These requirements are caused by the necessity to save fuel, to reduce emissions of pollutants into the atmosphere, to improve operational reliability, to reduce size and cost of spent materials, weight, noise level, to simplify manufacturing and operational processes. Use of gas as a fuel in the cities where number of engines is extremely large can significantly reduce environmental pollution. Some countries have separate environmental programs that encourage transfer of engines from gasoline to gas. At present, however, the use of gas engines in road transport is limited due to a number of technical and operational problems. Mathematical calculations and simulations are applied in order to solve this task and prevent possible problems in a manufactured. As part of the research to establish an influence of the diesel fuel ignition portion value in a gas-diesel engine on parameters of its operational process, it is necessary to develop an appropriate calculation method. In this regard, an analysis of methods and programs for calculation of the operational engine process has been carried out, and a method for calculation of an operational process for a gas-diesel engine has been developed in the paper. A computational study has been made in accordance with the developed methodology. The paper has revealed an influence of the diesel fuel ignition portion value on effective and environmental performance of an engine operation. The calculation has been performed for a nominal mode of the engine operation, gas fuel – propane-butane. Design parameters of a ГД-243-engine have been taken as initial data for the calculation. The following dependences have been established: as a diesel fuel ignition portion is increasing (replacement proportion of gas fuel with diesel), there is some decrease in engine power, and under the accepted conditions, there is an increase in CO2 with a decrease in CO and NO.
Optimization of Wastewater Treatment Process on Energy Costs at Truck and Tractor Washing Posts
Authors: Krutau A. V. , Dechko M. M. , Boika M. A.
Published: October 2019

The paper considers a process pertaining to purification of oily effluents while using electrocoagulation, electro-flotation and an electromagnetic hydro-cyclone, implemented with the help of a laboratory unit (Patent of the Republic of Belarus for the invention No 21229). The investigations have been carried out with the purpose to optimize specific energy consumption for the process of cleaning fuel and lubricants effluents. The following investigation methods have been applied – a literature review, a comparative analysis, an experiment execution, a mathematical modeling. Content of oil products in wastewater before and after treatment has been evaluated in the analytical laboratory of the Belarusian State Agrarian Technical University in accordance with standard methods. Purification of the oily effluents has been made with the help of a laboratory unit while using electroflotocoagulation method with removal of floated sludge in an electromagnetic hydrocyclone. This cleaning method makes it possible to increase a degree of water disinfection, provides a closed water supply, rational use of water resources, reduction of harmful effects of pollutants on the environment. An experimental design technique has been worked out and a three-level Box – Behnken design has been implemented in the paper. The problem concerning optimization of the purification process on energy costs has been solved without worsening the required concentration indices of petroleum products in water after treatment . Mathematical models have been obtained and optimal purification modes have been determined at the lowest specific energy costs and with sufficiently high degree of purification. Significance of regression coefficients has been estimated by Student criterion. It has been established that while using the proposed unit it is possible to obtain a degree of wastewater purification at automotive equipment washing stations with its performance G = 0.7 l/s, current density j = 150 A/m2. The degree of purification, determined by ratio of pollutant concentrations before and after purification, is up to 99.9 %. The results can be used in implementation of microprocessor control of cleaning mode while taking an initial concentration of pollution, unit capability, current density of an electroflotocoagulator as control action factors.
Kazan version of the classification of congenital heart defects of John Kirkland
Authors: Mirolyubov L. M.
Published: October 2019

The article is devoted to the analysis of classifications of congenital heart defects from a practical point of view. The variant of own classification of congenital heart defects with the substantiation of optimal terms of surgical correction is presented. The classification scheme allows predicting possible critical hemodynamic conditions in children with CHD both in the neonatal period and in other age groups. Used and is the basis in the choice of tactics of treatment of patients with CHD in the practice of cardiologists and cardiac surgeons in the Republic of Tatarstan for more than 15 years.
Urgensi Penerapan Sistem Ekonomi Islam
Authors: Fahrurrozi Fahrurrozi
Published: October 2019

Abstract: The ideology of capitalism cannot be separated from the understanding of European liberalism that occurred in the 18th century, where capitalism and liberalism were born in response to the dictatorship of the feudal lords and the church at that time. Meanwhile, the emergence of socialism in the 19th century, could not be separated from the role of Karl Marx who wrote a book The Communist Manifesto of a German socialist figure who had contributed in the revival of the union and unity of the workers and intellectuals who had more than a century been amputated by market mechanisms. The Islamic economic system regulates all economic activities, so that humans as economic agents cannot be free as freely as possible, there are limits set in the Koran and Hadith, all the objectives of economic activity cannot be separated from Islamic values, making and selling illicit goods such as alcohol is not permissible in Islamic economics. The Islamic economic system is not only used as an alternative economic system but is a solution of various economic problems today. الملخص: لا يمكن فصل أيديولوجية الرأسمالية عن مفهوم الليبرالية الأوروبية التي حدثت في القرن 18. لقد ولدت الرأسمالية والليبرالية استجابةً لديكتاتورية اللوردات الإقطاعية والكنيسة في ذلك الوقت. في هذه الأثناء، لا يمكن فصل ظهور الاشتراكية في القرن 19 عن دور كارل ماركس الذي كتب كتابًا بعنوان البيان الشيوعي لشخصية اشتراكية ألمانية ساهم في إحياء اتحاد ووحدة العمال والمفكرين الذين تم بترهم بواسطة آليات السوق منذ أكثر من قرن. ينظم النظام الاقتصادي الإسلامي جميع الأنشطة الاقتصادية، بحيث لا يمكن للبشر بوصفهم عملاء اقتصاديين أن يتمتعوا بالحرية قدر الإمكان، فهناك حدود محددة في القرآن والحديث، ولا يمكن فصل جميع أهداف النشاط الاقتصادي عن القيم الإسلامية، لا يجوز صنع وبيع سلع غير مشروعة مثل الكحول في الاقتصاد الإسلامي. لا يتم استخدام النظام الاقتصادي الإسلامي كنظام اقتصادي بديل فحسب، بل هو حل لمشاكل اقتصادية مختلفة اليوم. Abstrak: Ideologi kapitalisme tidak bisa dipisahkan dari paham liberalisme eropa yang terjadi pada abad ke 18, dimana kapitalisme dan liberalisme lahir sebagai respon atas diktatorisme para kaum feodal dan gereja waktu itu. Sementara itu kemunculan sosialisme pada abad ke 19, tidak lepas dari peranan Karl Marx yang menulis sebuah buku The Communist manifesto seorang tokoh sosialis Jerman yang telah memberikan sumbangsih dalam kebangkitan persatuan dan kesatuan kalangan buruh dan intelektual yang sudah lebih dari seabad diamputasi oleh mekanisme pasar. Sistem ekonomi Islam mengatur seluruh aktifitas ekonomi, sehingga manusia sebagai pelaku ekonomi tidak bisa bebas sebebas-bebasnya, ada batasan-batasan yang sudah diatur dalam al-Qur’an dan Hadits, seluruh tujuan aktifitas ekonomi tidak bisa di pisahkan dengan nilai-nilai Islam, membuat dan menjual barang-barang haram seperti alcohol tidak diperbolehkan dalam ekonomi Islam. Sistem ekonomi Islam bukan hanya dijadikan sebagai sistem ekonomi alternate tapi menjadi solusi dari berbagai permasalahan ekonomi saat ini.
Persepsi Akuntan Manajemen terhadap Penerapan Tax Planning
Authors: Septiano Renil , Sari Nila
Published: October 2019

Abstract: Tax planning is a means of fulfilling tax obligations well but the amount of tax paid can be reduced as low as possible to obtain the expected profit and liquidity. This study aims to see the effect of management accountants' perceptions on the implementation of tax planning. The type of research used is quantitative, using primary data. The population of the research was in Food Distributor companies in the Padang City. Respondents who were taken were employees who served as part of accounting staff, management and financial staff companies who worked at the Food Distributor Padang City. Selection of samples was selected using the Convenience sampling method with 30 respondents. Technical data analysis using simple regression analysis. The test results show that the perception variables of management accountants with a significant value of 0,000 < 0,05. Based on the test results it was found that the perception of management accountants has an effect on the implementation of tax planning  الملخص: يعد التخطيط الضريبي وسيلة للوفاء بواجبة الضريبية بشكل صحيح ولكن يمكن تقليل مقدار الضريبة المدفوعة إلى أدنى مستوى لأجل الحصول على الربح والسيولة المتوقعين. تهدف هذه الدراسة إلى دراسة تأثير تصورات المحاسبين الإداريين على تطبيق التخطيط الضريبي. نوع البحث المستخدم كمي، باستخدام البيانات الأولية. السكان البحثيون في شركات توزيع المواد الغذائية في مدينة بادانج ، وكان المشاركون في الاستبيان من الموظفين الذين عملوا في موظفي المحاسبة والإدارة وموظفي تمويل الشركة الذين عملوا في شركة توزيع المواد الغذائية في مدينة بادانغ. تم اختيار عينات مختارة باستخدام طريقة أخذ عينات الراحة أو أخذ عينات الملائمة مع مجموعة 30 من المشاركين. تحليل البيانات الفنية باستخدام تحليل الانحدار البسيط. تظهر نتائج الاختبار أن تصور محاسبي الإدارة متغير بقيمة كبيرة من 0،000 <0.05. بناءً على نتائج الاختبار، تبين أن تصور محاسبي الإدارة يؤثر على تطبيق التخطيط الضريبي. Abstrak: Tax planning merupakan sarana dalam memenuhi kewajiban perpajakan dengan baik tetapi jumlah pajak yang dibayar dapat ditekan serendah mungkin untuk memperoleh laba dan likuiditas yang diharapkan. Penelitian ini bertujuan untuk melihat pengaruh persepsi akuntan manajemen terhadap penerapan tax planning. Jenis penelitian yang digunakan bersifat kuantitatif, dengan menggunakan data primer. Populasi penelitian pada perusahaan Distributor Makanan di Kota Padang, Responden yang diambil adalah pegawai yang menjabat dibagian staff akuntasi, menejemen dan staff keuangan perusahaan yang bekerja pada perusahaan Distributor Makanan Kota Padang. Pemlihan sampel dipilih menggunakan metode Convenience sampling atau sampling kemudahan dengan jumlah 30 orang responden. Teknis analisis data menggunakan analisis regresi sederhana. Hasil pengujian menunjukkan bahwa variabel persepsi akuntan manajemen dengan nilai signifikan 0,000 < 0,05. Berdasarkan hasil pengujian didapat bahwa persepsi akuntan manajemen berpengaruh terhadap penerapan tax planning
Design Optimization for Drilling Development Wells
Authors: Al Kalbani Zakariya Abdullah , Moreno Carlos Alberto , Agguirre Abel Eduardo , Al Jahwari Mohammed , Sutherland Andrew , Elyas Mutaz
Published: October 2019

The successful drilling campaign from all aspects is all depending on a robust solution developed during the design phase on the well construction process. This paper describes the advance technical engagement between the operator and integrated drilling services provider to generate an optimum well design for drilling development wells in Sahmah field of block 7, in the south east of Oman.

Integrated Drilling Services (IDS) provider in Oman was awarded a contract to drill 10 firmed wells for a national client. One of the most challenging environments in the surface section is to drill and cement highly fractured and caved carbonate formation (UER) which prone to losses as this play a major risk and later deal with problematic shale formation in the same section. Moreover, the client decided to change the scope of some of the development wells and go for exploration pilot hole exploring deeper horizons to evaluate other potential hydrocarbon zones.

The engineering team have the opportunity to study the field in depth. As a result of analyzing offset wells data, geological and geomechanical studies, a new well design has been proposed which eliminates one section of the previous well design which was executed on some of the offset wells before. In the same proposal, the intermediate casing setting depth was been extended deeper successfully to accommodate the changes in the scope to explore deeper horizons.

The new proposed well design achieved reduction in well construction time and cost for the client enabling reduction in overall Authorization for Expenditure (AFE). This enabled the introduction of new technologies which improved performance. The drilling design consideration process in this paper can be used to provide a valuable insight for future projects where complex technical study in advance is the key to success.
Operating GOSP Disposal System Without Seawater Supply
Authors: AL-Mulhim Khalid
Published: October 2019

HdGOSP-2 was designed to be fully dependent on Haradh Water Injection Plant (WIP). Haradh WIP receives disposal water from HdGOSP-2 disposal system and sea water from Hawiyah Central Water Injection Plant (HCWIP). Therefore, Haradh WIP can only be run when HCWIP is online. As a result, if HCWIP is down, HdGOSP-2 total oil production is also locked due to lack of alternative solutions to inject disposal water. During the past three years, HdGOSP-2 oil production was locked for (13) days due to the loss of water supply from HCWIP. The idea is to operate (1) turbine driven injection pump solely with HdGOSP-2 disposal water for a temporary period to be fully independent from Hawiyah WIP. The current produced water rate at HdGOSP-2 is 120 MBD and in order to meet the minimum flow requirement for the injection pumps, a total of 90 MBD needs to be recycled. It has been evaluated the potential increase in water temperature due to recycling using HYSYS simulation revealing no significant temperature rise. In addition, the simulation output along with reliability & rotating equipment evaluation revealed that this option can only work if the pump discharge pressure is maintained above 2200 psig. This can be achieved by isolating some of HdGOSP-2 Flanks and reducing the number of water injection wells on service.

This mode of operation was started on April 26, 2018 and lasted for six (6) days. During this period, the sea water rate was gradually decreased to zero while maintaining HdGOSP-2 disposal water flowing through GT-4001 with partial recycle and without having any impact on HdGOSP-2 oil production rate or crude quality specifications.

Upon completing the 1st implementation of this initiative, HdGOSP-2 has produced total of 1.98 MMBOD of oil during the outage of HCWIP in 2018. HdGOSP-2 has produced 1.98 MMBOD of oil during the outage of HCWIP which is equivalent to $96,000,000 during six (6) days outage of HCWIP in 2018. The production gain will continue in the future whenever HCWIP is down.
Cost Effective Minimal Offshore Structure in Shallow Water Marginal Fields
Authors: Chatterjee Prabir Kumar , Shah Jinesh
Published: October 2019

This paper proposes a method of securing well conductors in shallow water open sea without installing a structural jacket. The method allows well completion at surface (above water) for subsequent easy production operation without installing mudline suspension system. Stability of the conductors against environmental loads will be ensured by a few tie members connected to seabed by small concrete blocks. Numerical studies have been carried out for one and two wells in 20.0m water depth to withstand directional environmental forces due to a maximum of 10.5m high waves. Only after a successful drilling outcome, installation of an offshore platform with more wells can be undertaken to facilitate production operation. If more than two wells is not commercially feasible from the same location due to low reservoir capacity, a cost-effective minimum structure is proposed for supporting immediate production operation.
Numerical Investigation of CO2 Sequestration as Hydrates in Produced Natural Gas Hydrate Formation with Different Intrinsic Permeability and Water Saturation Conditions
Authors: Ahmad Sheraz , Li Yiming , Li Xiangfang , Xia Wei , Chen Zeen , Wang Peng , Yin Zhiming
Published: October 2019

The phase transition field model equations for hydrate-bearing formation are proposed to analyze the variations in pressure, temperature, hydrate growth rate and other parameters during CO2 injection and storage as solid hydrates. The numerical algorithm results show that intrinsic permeability and water saturation has great influence on hydrate nucleation process. When the intrinsic permeability of sediment decreases from 100 mD to 10 mD and 1 mD, pressure distribution delays inside hydrate-bearing formation and indirectly it also suspends the hydrate growth process due to smaller hydrate growth rate. The slow hydrate nucleation speed affects other parameters variations like, temperature distribution, accumulative hydrate growth, CO2 permeability and 1st and 2nd region boundaries movement. The hydrate growth termination effect is observed near the wellbore region at different absolute permeability conditions. The hydrate growth suspension is more prominent when the intrinsic permeability reduces from 100 mD to 10 mD and 1 mD. Therefore, CO2 injection at low temperature and high pressure conditions may form hydrates but it seems challenging in lengthier formation. So, more than one injection facilities can solve this problem with less injection pressure.
Investigation of Enhanced Oil Recovery with the Upscaled Three Phase Flow Model in an Oil Reservoir
Authors: Rabbani Shahid , Abderrahmane Hamid , Sassi Mohamed
Published: October 2019

For past few decades, Enhanced Oil Recovery (EOR) has been posing an exigent task for researchers in oil and gas industry. Traditionally for many geological formations, water and gas are used as displacing fluids for oil recovery. More recently foam–a dispersion of liquid in gas–has proved to be highly successful than traditional fluid displacement methods to recover trapped oil in the porous rock. Foam increases oil displacement efficiency by controlling gas mobility and gravity override. In this work oil recovery efficiency using water, gas and foam flooding is compared. To determine optimal oil recovery scenario, we perform numerical modelling for two-phase immiscible flows in porous media and perform simulations to determine oil recovery from water, gas and foam flooding. 2D two-phase and three-phase flow models are created in COMSOL and effects of viscous instabilities and permeability of different ground layers on recovery factor are investigated.
New Techniques of Through-Barrier Diagnostics to Improve Integrity Management Decisions in Reservoir Development of Complex Reservoirs
Authors: Gibrata Muhammad , El Sayed Mohamed , Naguib Hashem Mohamed , Aslanyan Irina , Minakhmetova Roza , Skutin Vasiliy , Abasher Doha , Abu-Rahmoun Husam
Published: October 2019

The mature oil field in the Caspian Sea was originally discovered in the 1960’s and more than 100 wells were drilled in the field. When Dragon Oil inherited the field in the 90s, it had a well stock of varying issues and complexities that required a full field well integrity review to cover the entire well lifecycle. Dragon Oil had a field-wide detailed well status report demonstrating that many wells had integrity problems related to sustained annulus pressure (SAP) in a variety of annuli, which, when risk-ranked, clearly identified those wells that needed intervention.

This paper will demonstrate the cases where slickline-conveyed cased-hole memory logging tools were run at three different well lifecycle stages: Well drilling - to detect the shallow water or gas source and perform a remedial jobProduction operations - to identify sustained annulus pressure sources so remedial solutions could be prepared to cure high risk wellsPlug&Abandonment planning - to provide a status report of downhole well conditions so that a cost-effective abandonment programme could be planned and executed.

In each of the above cases, the data collected during logging operations provided a clear identification of the related well issues and was sufficient to allow detailed planning and execution of remedial jobs and abandonment operations.
Digital Rock Technology Accelerates Carbonate Rock Laboratory Analysis
Authors: Klemin Denis , Serebryanskaya Assel , Savelev Oleg , Melnikov Sergey
Published: October 2019

This paper describe an application of combined experimental and digital technology workflow for field appraisal. It includes the description of heterogeneous low permeability X oil field located in the southeastern part of the Kurdistan Region of Iraq and its field development planning (FDP) challenges.

An integrated laboratory study of low permeability carbonate reservoir rocks (dolomitic limestones) included a digital rock (DR) workflow that accelerated the time to complete core analysis program while bringing vital information about the pore-scale flow dynamics. The DR workflow combined high-resolution digital rock imaging, digital fluid models of reservoir brine and live oil samples, detailed wettability model for sample aging and boundary conditions in digital coreflood experiments. DR imaging spanned from micro-CT for meso- and micropores to high-resolution SEM imaging of submicrometer porosity. Direct HydroDynamic flow simulator was used to model multiphase flow in digital experiments by solving equations of the density functional hydrodynamics (DFH). These equations are conservation laws for the mixture of chemical components, momentum, and energy with constitutive relations involving Helmholtz free energy or the entropy functional.

Samples were prepared for DR analysis and their representativeness was verified by obtaining routine properties of original plugs, trims, and mini-plugs selected for high-resolution DR imaging. We established the routine core analysis (RCA) properties of samples using DR and compared them with experimental data. Porous plate digital experiments were performed to obtain air-brine capillary pressure curves on all samples, with DR data verification with laboratory data on selected samples. A set of steady-state (SS) relative permeability digital experiments were then performed with live fluids at reservoir conditions. DR models were first fully saturated with brine and then de-saturated to water saturation that matched reservoir water saturation estimated from well logs. The SS cycle was performed after extended aging to establish a mixed-wet condition. SS relative permeability curves were obtained for all studied samples. DR modeling enabled looking at the dynamic changes of phase saturation in pores and significantly accelerated the laboratory program by performing porous plate tests 100-500 times faster and SS tests 20-50 times faster than conventional analysis using live fluids at pressure and temperature conditions surpassing operating ranges of laboratory equipment.

The comprehensive combined study (both laboratory tests and DR analysis) results determined the reservoir flow properties within the entire permeability range. It allowed to reduce uncertainties in predicting production levels, improved the forecast quality of the hydrodynamic model and reduced the difference between the minimum and maximum estimates of geological and recoverable reserves.
Data-Driven Neural Network Model to Predict Equivalent Circulation Density ECD
Authors: Alkinani Husam H. , Al-Hameedi Abo Taleb , Dunn-Norman Shari , Al-Alwani Mustafa A. , Mutar Rusul A. , Al-Bazzaz Waleed H.
Published: October 2019

Equivalent circulation density (ECD) is vital in drilling operations. Poor management of ECD can lead to many drilling obstacles that can increase the delivery time of the well. The aim of this study is to utilize artificial neural networks (ANNs) to create a model to estimate ECD prior to drilling.

Data of more than 2000 wells collected from multiple sources worldwide were utilized in this work. An ANN model was created with one hidden layer and 12 neurons in the hidden layer. The data were clustered into three data sets; training (70% of the data), verification (15% of the data), and testing (15% of the data). Ten training algorithms were utilized to train the network, the training algorithm with the lowest mean squared error (MSE) and the highest R2 was selected to achieve the best predictive model. Bayesian Regularization (BR) algorithm was selected to train the model because it had the highest R2 and the lowest MSE.

The results showed that the created model can predict ECD within an acceptable margin of error. The overall R2 of the model was 0.982 which is considered very good. Alternatively, given a target of ECD, the created model can be utilized in reverse to obtain the desired ECD by altering the key drilling parameters affecting the ECD model (the inputs). This will help the drilling personnel to optimize ECD in the field.

Intelligent systems and machine learning have proven their effectiveness in solving complicated problems that cannot be solved analytically. With the large historical drilling data available in the oil and gas industry, machine learning and intelligent systems can be used to make better future decisions that will help to optimize the drilling operations.
Artificial Intelligence Opportunities for Environmental Protection
Authors: Hojageldiyev Dayanch
Published: October 2019

Artificial Intelligence systems utilize a variety of technologies making it possible to produce comprehensive, nonetheless easy-to-use tools, which can be used by Health, Safety and Environment professionals in oil and gas industry. The objective of this paper is to provide an overview of AI opportunities for constantly evolving oil and gas business in addressing such issues as environmental protection.

This paper examines a variety of AI applications aimed to provide support to HSE professionals in reviewing big batches of random data and identify important patterns for further planning; develop viable models to assist examination of various event scenarios, predict and mitigate emergencies. As with any data-driven AI tool, the type and amount of data available are perhaps the decisive factors when selecting the AI agent environment. The HSE fields with ample amounts of workable data for machine learning will be reviewed.

AI systems utilize a variety of technologies making it possible to produce comprehensive, nonetheless easy-to-use tools, which can be used by HSE professionals in their daily activities. Artificial intelligence technologies today offer a pool of decision-making models for oil and gas industry. The tools developed based on the AI technologies and machine learning can help specialists working in the fields of HSE to advance their efforts in environmental protection, and contribute to mitigating climate change and weather disaster issues, biodiversity conservation, waste reduction, water security, healthy oceans, and clean air. There are over 80 areas in environmental protection initiatives where the AI and ML models are actively used. These tools prove to be more effective in executing routine tasks with higher accuracy and faster completion rates. The AI is also progressing in unsupervised decision-making, which however, raises concerns among the scientists and law-makers as algorithms using historical data may not only incorporate previous discriminations and biases, but reinforce them.

Artificial intelligent systems using machine learning are constantly improving in accuracy, presenting an opportunity for constantly growing oil and gas business in improving their environmental compliance activity, and developing a well-praised image of a sustainable community partner.
Comprehensive Evaluation of Water Breakthrough With a Novel Method to Estimate Water Production
Authors: Al Shehri Dhafer
Published: October 2019

Produced water is inevitable in the life span of a reservoir despite the challenges associated with it. To make an informed decision on economic and engineering design, it is essential to establish post water breakthrough trend to predict water production and to design surface facilities to handle the volume of water that will be produced. Several correlations and models have been proposed in the literature; however, each of the models could solve the problem from which it was derived. Most of the traditional models represent water cut as a function of cumulative oil production or time which is only achievable when accurate water cuts are available.

This paper analysis post water breakthrough performance using empirical models. In this proposed method, the water cut (WC) was redefined and plotted against the oil flow rate (Qo). Different models were developed to capture the trends of the plotted graph. It is interesting to note that during water breakthrough, there exist exponential, hyperbolic and harmonic increase in water production throughout the reservoir life span. The model was validated with producing field data and has proven to be robust and can be a reliable tool for estimating water production.

The newly developed model in this paper offers an advantage of predicting the corresponding WC at any given Qo and bottom hole pressure.
Petrophysical Evaluation Challenges in Shallow Gas Reservoir Deposited in Sabkha Environment, Case Study, UAE
Authors: Abdelaal Atef , Hanaee Ahmed Al , Taher Ahmed , Deminova Anna , Khan Riaz , Kurniawan Redy , Vantala Aurifullah , Akl Osama
Published: October 2019

The petrophysical evaluation for Sabkha environment is very challenge due to high reservoir heterogeneity and complex mineralogy in addition to existing of multi-lamination that have various thickness ranging from 1 to 20 ft., also these kinds of reservoirs normally have very high formation salinity that impact as well the water saturation calculations.

In 2018, a unique worldwide biogenic shallow gas reservoir was discovered in Onshore Abu Dhabi, UAE in Miocene Sabkha deposits while drilling a dedicated well for deeper reservoir, the average reservoir gross thickness is about 4500 ft. with hundreds of intercalations from Clay, Limestone, Dolomite, Marl, Anhydrite and Halite.

This paper presents the detailed challenges for such reservoir regarding the petrophysical evaluation (including but not limited to porosity calculations, water saturation evaluation by different methodology, net to gross ratio, log and core data integration, definition of high potential spot for testing, etc..) Moreover, the way to manage and mitigate these challenges in addition to testing technology and results.

So far Five dedicated exploration wells were drilled in this reservoir at which a complete set of logs were acquired in addition to collecting of core footage about 4560 ft. from two wells and analysis is ongoing, also Rigless testing was done for 3 wells. In general, based on collecting data the reservoir properties showed very tight reservoir (permeability < 0.01 md) with high mineralogy complexity as well as high formation salinity (+ 300 kppm). Good Total Organic Carbone is also measures across the reservoir that confirmed the ability to produce Microbial gas.

As a results of the integrated study, the sweet spots across the reservoir were identified and tested, accordingly placement for horizontal development wells as well as stimulation technology are optimized
Proposing a New Eco-Friendly Drilling Fluid Additive to Enhance the Filtration Properties of Water-Based Drilling Fluid Systems
Authors: Al-Hameedi Abo Taleb , Alkinani Husam H. , Dunn-Norman Shari , Al-Alwani Mustafa A. , Alshammari Abdullah F. , Albazzaz Hussien W. , Alkhamis Mohammed M. , Rusul A. Mutar , Al-Bazzaz Waleed H.
Published: October 2019

The main objective of this paper is to develop a new material used to control the seepage losses and combat issues regarding thick mud cake. The plan is to develop a biodegradable waste material from Grass, which is environmentally friendly to be utilized as an alternative material to address filtration problems. Raw material from local Grass in the USA was used to construct the fibrous fluid loss control agent (Grass Powder). The lab procedure consisted of crushing and grinding process to assemble the samples to be ready for preparation. Spud mud samples were used as a guide to indicate filtration control. The material was tested to generate results from the experiments conducted at surface conditions to determine the reduction in the volume of filtrate and mud cake. Based on the experiments conducted, Grass Powder (GP) can be applied to treat problems associated with the seepage loss in the drilling operations. The grass availability, being eco-friendly, low cost, and the simple method of Grass Powder preparation by using grinding and crushing can prove to be a suitable replacement for conventional materials used to control filtration.

Then, the results of Grass Powder were compared to starch, commonly used conventional additive. The results showed that Grass Powder decreased the fluid loss by 44% at 1% (7 grams) concentration of GP, and the filter cake was enhanced as well when comparing it to the reference fluid. While the starch material showed an improvement in seepage loss by 40% at 1% (7 grams) concentration when comparing it to the reference fluid. In addition, starch was less efficient in improving the filter cake as compared to Grass Powder. Consequently, GP laboratory outcomes slightly showed better performance as compared to starch additive, suggesting the feasibility of Grass Powder to be used as fluid loss control agents.

In brief, these experimental results exhibit that Grass Powder has the potential to be utilized as biodegradable drilling fluid additives replacing chemical additives and reducing the amount of non-biodegradable waste disposed to the environment.
How Engineering Design Enabled Drilling the Longest Intermediate Section
Authors: Galaby Amir , Cardenas Miguel , Cengiz Husnu Ozgur , Kosberg Birgitte Ruud , Sanderson Martin , Krikor Ara
Published: October 2019

As the demand for natural gas continuously increases to meet electricity production needs, more alternative natural gas sources are usually required to cope with the increased demand in the summer months. In South Iraq, this situation is the main driver for exploiting economically feasible and efficient solutions in finding additional natural gas resources. As a result, the Iraqi government embraces the challenge by drilling deeper formations which are gas bearing, with limited experience in such fields. In the most recent appraisal campaign for these gas fields, performed in 2015 and 2016, one of the main challenges were bits and bottom hole assembly (BHA) failures while drilling through different interbedded and abrasive formations. Changing the bits type, BHA centralization, drive system and drilling parameters did not result in significant benefits.

For the 17 ½" section, up to six (6) independent runs were required to successfully drill the entire section. The success was limited due to severe shocks and vibrations, high axial forces and high torque that caused failures on downhole mud motors and bits, leading to fishing operation and severe non-productive time. Other problems like unstable drilling parameters, extremely low rate of penetration (ROP) and poor wellbore quality were observed, leading to excessive reaming and backreaming as well as stuck pipe events and difficulties to maintain well verticality. To avoid and minimize the impact of these challenges, a comprehensive engineering team performed various finite element analysis on the interaction between BHA, drilling bit and formations drilled. The conditions on which the wellbore was maintained in the offset wells with its drilling fluids strategy and drilling parameters were reanalyzed. The bits selections were revised, identifying areas of opportunity to introduce fit for purpose technologies on cutters and bits profile. The ultimate challenge was to drill the full 1800 m of the section in one run avoiding any BHA related failure.

The results exceeded expectations in the fourth well, where no BHA related failures were observed, and the drilling bit was able to drill the full 1800 m. Connection practices were also optimized. This enabled an improvement in the wellbore quality based on caliper logs. Improved wellbore conditions allowed a smooth casing run and consecutive cement job. This paper will discuss the engineering methodology followed to achieve this important milestone in one of the few gas fields in Iraq. It will go through the details of the technologies implemented on BHA analysis, bit selection, drilling parameters optimization and drilling fluids strategy implemented.

The objective of this paper is to share with the oil and gas industry a methodical approach for efficient drilling, and how to address drilling challenges with technology introduction and engineering design.
Taking A Nap: Passive EOR Implementation for Resilient Management of Cost and OPEX for A Polymer Flood Project with Horizontal Wells in South Sultanate of Oman
Authors: Al-Jumah Ali , Saadi Faisal , Harthy Khalfan , Lawati Sakeena , Khaburi Saja , Battashi Fathiya , Al Aghbari Dareen , Harthi Mahmood
Published: October 2019

This paper will discuss the evidence gathered proving the presence of Nothing-Alternating-Polymer (NAP) mechanism, in a current Polymer flood pattern during injectors offline periods, and the extension project designed to test and control NAP in conjunction with a nearby pattern in a horizontal wells environment. This project will help unlock a pragmatic Fullfield development, and highlight the associated benefits from a project’s perspective, leading towards huge savings and flexible operating conditions. Practical considerations and suggested operational methodology is also discussed.
AI-Based ESP Optimal Control Solution to Optimize Oil Flow Across Multiple Wells
Authors: Krikunov Dmitry , Kosyachenko Semen , Lukovkin Dmitry , Kunchinin Alexander , Tolmachev Roman , Chebotarev Roman
Published: October 2019

Objectives/Scope: The proposed paper will describe the results and operation principles of the developed AI-based solution for the optimization of operating modes of electrical submersible pumps (ESP). The solution allows exploration and production companies to increase the oil flow rate from ESPs without additional capital investments. The solution is based on the technical possibility of ESP mode adjustments in a certain range of motor frequencies and control types.

Methods, Procedures, Process: The hypothesis is that there is a certain ESP operation mode in each period of time which ensures the maximum daily oil and gas flow rate in the long term. The proposed solution uses statistical methods to ensure data sufficiency and stability and employs custom algorithms to conduct problem-specific data preprocessing. The "well-reservoir" model is the combination of physical (i.e., pump model) and machine learning (ML) models. The ML part of the solution was designed for the short- and long-term predictions of well-reservoir system response. However, the model faced constraints such as current frequency, load and amperage.

Results, Observations, Conclusions: The following results were delivered: data collection and preprocessing pipeline was built, a hybrid physical-ML prediction model was designed and trained, and a numeric optimization model which uses outputs of the hybrid prediction model was designed to recommend multi-well operation modes. The solution has been successfully deployed and tested for 6 months on 500 oil wells in Western Siberia. The designed ESP optimal control solution could enhance the efficiency of oil extraction by boosting oil well production rates by 1.5% with no additional capital investment, as proven during the production phase. Thus, the proposed "reservoir-well-pump" system modeling approach showed efficiency and superiority over the previous control methods used by oilfield operators.

Novel/Additive Information: To the authors' best knowledge, the present paper is the first work covering research, development and production testing of hybrid physical-ML methods in the optimal control of ESPs with respect to optimization of oil flow. Application of some known statistical methods to the problem of provision of reliable data to the model is additive to the current body of knowledge.