bluuebunny/crossref_metadata_2025_split huggingface dataset:
Micro-Displacement Mechanism of Divalent Cations Activated Polymer Flooding In A Complex Conglomerate
Authors: Liu Rui , Pu Wanfen , Ushakova Alexandra , Ren Hao , Du Daijun , Luo Qiang , Gou Rui , Luan Huoxin 
Published: October 2019

Abstract
The conglomerate reservoirs of south block Qidong, Xinjiang Oilfield, NW China are one of the largest conglomerate reservoirs worldwide and have employed polymer-based chemical flooding pilot tests since 2016. But the output is less than 10% due to the harsh divalent cations concentration and the complex fluids distribution in microscale. It is important to design a novel divalent cations resistant polymer and then to elucidate its micro-reserve displacement mechanism in a complex conglomerate. A novel core-shell like polymer (CSPAM) composes of nanosilica as the core and polyoxyethylene modified polymeric chains as the shell is synthesized via a facile method. The thickening performance of CSPAM activated by divalent cations is explained using advanced rheometer and scanning electron microscope. A visual conglomerate lamination model combined nuclear magnetic resonance online experiments are conducted to investigate the micro-unrecovered oil displacement mechanism of CSPAM flooding: the distribution of micro-remaining and micro-residual oil after the earlier waterflooding are quantified; latter, the reserve utilization and displacement behavior of CSPAM flooding on the pore space scale are characterized. Within the Ca2+/Mg2+ concentration of 12000 mg/L, the electrostatic bridging between Ca2+/Mg2+ and ethyoxyl groups of CSPAM induces an interlacing transient-network, which activates a tenfold increase of viscosity and of longest relaxation time compared to these of CSPAM solution without adding salt. The conglomerate rock shows a complex pore-and-throat structure, resulting in severe heterogeneity and rapid water cut. The oil recovery by the earlier waterflooding is approximately 35% of OOIP (original oil in place), and the cluster of remaining oil in a disconnected state and oil resident in blinds pores occupies a major proportion of unrecovered oil. Significant reduction of oil saturation is achieved by CSPAM solution at low concentration of 1000 mg/L in harsh brine. Approximately 28% of incremental oil recovery factor with cumulative oil recovery higher than 63% OOIP is achieved by 0.5 pore volume of CSPAM flooding and chase waterflooding. The reserve utilization of CSPAM is 23.1% for large pore spaces, 13.2% for intermediate pore spaces, 11.6% for confined pore spaces, and 5.67% for minimum pore spaces, respectively. This research constructs a novel water-soluble polymer CSPAM with divalent cations activating viscosification, and elucidates the micro-displacement mechanism of CSPAM through quantifying the remaining oil and residual oil distribution, and reserve utilization of CSPAM on the pore spaces scale. The results will provide the substance and technique supports for future application in harsh salinity and complex pore structure conglomerate reservoirs.
Modeling Gelation Time of Organically Crosslinked Polyacrylamide Gel System for Conformance Control Applications
Authors: Al-Anazi Amer , Al-Kaidar Ziyad , Wang Jinxun 
Published: October 2019

Abstract
Gel-based conformance control has been successfully applied in both sandstone and carbonate reservoirs. However, deep conformance-control in high-temperature reservoirs is still a challenge due to fast gelation. Gelation time depends on several factors. Successful modeling of the different parameters’ effects on gelation time is invaluable for formulation optimization to realize sufficient gelation-time for deep-diversion. In this work, a laboratory study was conducted to investigate and model gelation-time for organically-crosslinked Polyacrylamide formulations.
Sulfonated polyacrylamides with different molecular weights were used. The solutions were organically crosslinked using a polyethylenemine (PEI). The effects of different factors including temperature, brine salinity, pH, and polymer and cross-linker concentrations on gelation time were investigated using bottle tests and rheological measurements. For bottle tests, the solutions are prepared and aged in an oven. The vials are then retrieved and visually examined for gelation before being returned to the oven. For rheological measurement, dedicated solutions are prepared in separate vials and aged in the oven. Each vial is then retrieved where the solutions viscous and elastic moduli are measured.
The results indicate that polyacrylamide/PEI gel exhibits good thermal stability and gelation time reaches up to two and a half days at 95°C. The gelation time decreases with increasing temperature, polymer molecular weight, and polymer and crosslinker concentrations. However, there were lower limits for the polymer and crosslinker concentrations below which gels were not observed. Brine salinity and pH showed a wide range of effects on gelation time. Gelation time slightly increases with increasing the solution salinity at a fixed pH of around 8.0. A mathematical model was developed based on the experimental results to capture the effects of the main parameters. The predictable equation of gelation time was constructed using multivariable regression method, and the model successfully predicts the gelation time of the conformance control system at a fixed pH value of around 8.0. The good agreement is illustrated by the R-square value being around 98%. Furthermore, the model shows that temperature posses the highest impact on gelation time followed by the crosslinker concentration and brine salinity.
The developed mathematical model can be used to predict the gelation time of a polyacrylamide-PEI gel system. In addition, it can be utilized to optimize a given gel design and further validate the applicability of a given polymer/crosslinker formulation for deep fluid diversion application.
Development of Low-Permeability Reservoirs by Increasing the Mobility of Water in a Porous Medium Using a Chemical Reagent - Super Fluid Water SFW
Authors: Zatsepin Vladislav , Gubaidullin Farid , Ushakova Alexandra , Miftakhov Salavat 
Published: October 2019

Abstract
The considered "Super Fluid Water" (SFW) is developed aqueous solution of polyelectrolytes with extra low concentration. The aim of the present work is laboratory investigations and field studies of the water with reagent flow in porous media. Change in hydrodynamics of water flow – the mobility increase was observed for the SFW additives.
Filtration studies of changes in the value of the residual resistance factor for core samples with different permeability were carried out. The conducting field tests were held using standard techniques and methods of field geological and geophysical studies. Temperature and profile logging were performed at different flow rates, with water and water with SFW injection (SWF concentration up to 1%).
Laboratory studies have shown that the value of the residual resistance factor is lower than the value of the absolute permeability of the core sample, and the dependence is approximated by the power function. The established laboratory dependence confirmed the possibility of using the SFW reagent for conformance control in injection wells, which determined the goals and objectives of field studies.
The field studies were performed (we provide the information about the success treatments of 4 injection wells, no information about the unsuccessful treatments) and showed that the use of the reagent SFW leads to a dramatic increase of the injection capacity of the wells (210% and more).
Estimation of the injection capacity profile before and after the use of SFW reagent showed the extension of operating intervals by including of extra low permeable layers (less than 1-2 mD) not previously drained by water.
At the same time, the efficiency of SFW technology in these conditions is estimated to be higher than the technologies associated with gas injection into the reservoir.
The achieved results allow us to assert the prospects of using SFW technology for the development of low-permeable reservoirs. The employment of this technology in the practice of oil recovery engineering will increase the efficiency of field development and oil recovery by 15-20%.
Drilling Extended Reach Well with Eight Fishbone Sidetracks: East Messoyakha Field
Authors: Akhmetov Marsel , Maximov Maxim , Lymarev Maxim , Malyshev Yevgeny , Vasilyev Roman , Glushenko Nikolay , Rakhmangulov Farit , Frolov Denis 
Published: October 2019

Abstract
This article describes an experience drilling a multilateral "fishbone" well with eight sidetracks and contains geological substantiation of this technology from the production-increase point of view as well as actual results of the eight-lateral well start up and operation. For fishbone wells where each wellbore is a sidetrack from the previous hole, one of the fundamental drilling aspects is kickoff from the parent wellbore.
This article is based on the analysis of 114 kickoffs in production wells of the East Messoyakha field where kickoffs with a rotary steerable system (RSS) and performance drilling motor (PDM) were determined beneficial. Additionally, strength analysis and hydraulic calculations for drilling of the longest fishbone at the East Messoyakha field with an extended reach drilling (ERD) factor of 2.95 are discussed. Further, this article highlights the main potential of this technology development and its limitations during a further massive application.
Automatic Drilling Fluid Measurements
Authors: Taugbøl Knut , Brevik Jan Ove , Rudshaug Bjørn 
Published: October 2019

Abstract
The drilling fluid properties are critical for drilling parameters such as ECD (equivalent circulating density), surge and swab pressures and hole cleaning properties. To be able to optimize drilling parameters and improve drilling efficiency also the drilling fluid must be at optimum specifications.
To have a more proactive fluid engineering where the drilling fluid at all times is as desired continuous measurements of drilling fluid properties are necessary. This paper will present the development of new equipment for offshore use for automatic viscosity and density measurements. The paper will discuss the technology in use, the implementation and qualification into harsh offshore environment as well as the resulting data obtained, transformed into digital data received at onshore operation centers.
The measurements of drilling fluids properties and chemical compositions have been more or less unchanged for decades. The tests in use are manual and performed by the mud engineer normally four times a day. Based on these tests the fluid properties are engineered within given set points of selected parameters. This limited number of tests will often drive the fluid engineering into a reactive mode, where fluid properties must be adjusted due to drift in measured values.
In this paper the experiences from introducing continuous measurements of drilling fluids density and rheology will be presented. Automatic measurements have been introduced by an operator on several offshore installations, both semi-submersible drilling rigs as well as jack-ups and fixed platforms. The use of the data in the fluid engineering process as well as in the drilling process will be discussed.
Drilling Fluid parameters can now be measured automatically on the rig. The fluid properties can then be monitored from operation centers 24/7.This ensure improved quality of drilling fluid. When this is performed in combination with online hydraulic calculations improved drilling performance is obtained.
Multilateral Wells With 3-String Casing Design as the Next Stage of Drilling Technology
Authors: Sirotin Denis , Mukhametzyanov Ildar , Grunov Ilya , Teregulov Oleg , Sunarchin Marat 
Published: October 2019

Summary
Continous improvement of technology and operating procedures is a key to the oil and gas industry. One of the ultimate goals of such improvement is to reduce drilling time and, consequently, save well construction costs. Drilling multilaterals in one run, using rotary steerable systems (without pulling out of hole for changing BHA for kick-off proceduce) has become the first step change enabling shorter drilling cycles.
In 2018, a project was designed to drill both horizontal and transport sections of a multilateral well in one run. According to this methodology, one 146mm casing is run instead of two: 178 mm and 114 mm casings. In case of succefull implelemtation, this project will reduce well construction time by more than 15 days.
The Results of Research and Development Project: Mobile Driller. Immediate Provision of Information to The Employees at a Drilling Site
Authors: Andreev Anton , Zimoglyad Mikhail , Gorbunov Aleksei , Sharipov Rafael , Nagovitsin Vladimir , Chuikov Vitalii , Kugatov Petr , Stelmashuk Anton , Abaltusov Nikolay 
Published: October 2019

Abstract
«Mobile Driller» is a part of «Digital Drilling» IT Project aimed at developing and implementing IT solutions, which make it possible to plan, assess and analyze the operations in the process of well construction and response to deviations in real time.
The main target of "Mobile Driller" Project is to find the solutions for immediate provision of the drilling rig employees with information. The project implementation resulted in a set of technologies (audio, video equipment, warning panels, etc.) for operation under real climate conditions of Far North and a completed prototype of the system for informing the employees.
The market of the available hardware solution models was analyzed to develop a set of technologies. The possibility to use in the areas of explosive hazardous atmosphere was taken into account when selecting the models.
The selected equipment package was assembled and tested at a drilling site in Novoportovskoye oil-gas condensate field.
The testing was conducted at temperatures from −39°C to +24°C;
Thirteen equipment usage algorithms were implemented for four types of the employees: supervisor, toolpusher, driller and driller's assistant.
The feedbacks from the users were recorded by means of check-lists and individual interviews.
The list of recommendations was drawn up based on the testing results.
The following results were obtained in the process of the Research and Development Project implementation:
The algorithms were developed to inform drilling rig employees about current status of implementation and changes of a drilling plan, upcoming operations, performance indicators, revealed deviations and critical situations; The optimal means for warning/informing the employees were selected: videowalls, smartphones, tablet computers, fitness bands, visual signal devices, hard buttons, wired and wireless headsets, AR/VR devices; the prototype of the system was developed to control all the devices and implement information provision algorithms.
The tests at the drilling site of Novoportovskoye oil-gas condensate field revealed that the equipment was operating consistently under real climate conditions, which include low temperatures (below −40° C) and precipitation.
The drilling rig employees evaluated every algorithm and equipment. Based on the evaluation results it was determined that the system allows to effectively communicate the information to the employee thereby reducing the information delivery time and improving the response rate.
Based on the project implementation results the objective information about possibilities to use the information provision system under Far North conditions was obtained. Due to "Mobile Driller" the employees are immediately informed about upcoming operations, performance indicators and revealed deviations.
Case study: Saving Days via Change of Connection Practices While Drilling
Authors: Ruzhnikov Alexey 
Published: October 2019

Abstract
One of the most common operations while drilling is the connection of drill pipes after every stand drilled. The main concern during this operation is to ensure that annulus around the BHA and drill string is clean of any cuttings, when often excessive time spent to achieve it. This manuscript discusses modeling, field implementation and operational observations of changing the standard practices, what led to significant time reduction while drilling vertical, deviated and extended reach (ERD) wells.
The most common worldwide practice is to wash / ream a stand up and down prior to connection to remove any potential cuttings around BHA. Having this in mind the objective was set to minimize this time as much as possible towards full elimination. To accurately predict the cuttings lifting forces, annulus cleanliness, hook load fluctuations advanced modeling combining torque, drag and hydraulics was developed. The model considers all the key parameters such as drilling fluid density and rheology, BHA configuration, pumping rates, wellbore geometry, temperature and pressure effects, etc. and can estimate the time required to spend at the end of every stand.
A total of up to one hundred jobs were simulated and followed by the field implementation in the different sections, which were ranged by bit size (from 17-in. to 6-in.), inclination and complexity (from zero to 90 degrees, including ERD wells) as well as other affecting parameters such as losses, wellbore stability etc. The data from the initial wells were crosschecked vs available MWD/LWD data (as equivalent circulating density, annulus pressure while drilling, temperature etc.) to confirm the results of the simulations.
As a result, new connection practices were developed with minimum clean out time prior to a connection. Two examples: in the vertical wells the pre-connection time was reduced almost to zero and only one-minute drill-off now done; in deviated wells including ERD a standard approach of washing up/reaming-down a stand was replaced to 2 − 3 minutes drill-off. Together with other changes it not only allowed the decrease a connection time by up to 90% without the negative incidents like stuck pipe, but also minimized impact on the bottom hole assembly (BHA) components happening due to off bottom stick / slip. This resulted in great time savings, where over 2 days can be saved for 20,000 ft wells vs standard practices.
The manuscript describes an engineering-based approach to connection practices which allows to shorten well construction time and decrease the well cost without additional risk.
Basic Principles of Gazprom Neft'S Modular Strategy for Field Infrastructure Development
Authors: Atnagulov Albert , Panov Roman , Khasanov Mars , Batrashkin Valery , Sugaipov Denis , Ismagilov Rinat 
Published: October 2019

Abstract
Today, complex projects with a high degree of uncertainty relating to the reserves and geology increasingly dominate the portfolios of promising assets of oil producers. Successful development of such oil deposits requires novel approaches. One of these approaches suggests using modular technologies for field infrastructure development purposes that secure effective performance in the face of geological and production uncertainties. The article offers a summary of the basic principles of modular strategy that have been developed and deployed by Gazprom Neft.
Application Rationale of Well Flow Test Complex Modules Covering Well Shut-in at the Bottomhole in terms of Eastern Siberia Carbonate Reservoirs Study
Authors: Arbatsky Timur , Shchurenko Alexander , Dadakin Nikita , Nukhayev Marat , Yamalov Ilnur , Rymarenko Konstantin 
Published: October 2019

Abstract
The paper presents the experience of oil and gas exploration in the fields of the Irkutsk region. The geological features of the studied facilities dictate a practical approach and the use of compact and efficient technological solutions that can later be successfully applied to a large number of fields with similar geology. The paper highlighted an optimized complex of works on the development and testing of wells target objects in a cased wellbore, using the technology of "the well shut-off at the bottomhole".
This arrangement ensures the effective implementation of work on the development of target objects and allows for high-quality registration of the bottomhole pressure dynamics. This engineering solution allows to perform a full cycle of hydrodynamical studies of well (well test) for a target interval in a relatively short time. The use of a tube bank significantly reduces the wellbore storage eand allows to obtain detailed data reliably characterizing reservoir properties and the structure of the reservoir under study.
The article describes the technology of hydrodynamic studies, with the well shut-off at the bottomhole. The article deals with the research problems of highly productive, flowing facilities, with a concrete example and a detailed analysis of technological features, interpretation options, possible complications and measures for optimization. The possibility of replicating technology in various geological and technical conditions is considered.
Involvement in the Development of Undeveloped Areas in Mature Fields
Authors: Asmandiyarov Rustam , Staritsyn Maksim , Zulkarniev Rustem , Studinsky Roman , Vorobyov Dmitry 
Published: October 2019

Abstract
Most of the Russian fields have entered their final stage of development; however, they contain a large amount of remaining recoverable reserves accumulated in unworked areas.
To involve the unworked areas, a selection method has been developed to select wells for in-fill drilling.
The method includes the following main stages: Identify the areas with remaining recoverable reserves; select the least depleted areas; place in-fill wells; assess geological and development risks; calculate potential production rates; develop rating and carry out expert assessment.
The method has been tested on other Brownfields, i.e., - Vyngapurovskoe, Sutorminskoe, Vyngayakhinskoe, Sugmutskoe, Kholmogorskoe, Yety-Purovskoe, Vostochno-Pyakutinskoe and Romanovskoe. Based on the estimated production rates of the wells and geology and development risks, as well as the reserves being involved, a through rating of the wells has been prepared for infill drilling. Expert assessment has identified 265 wells for top priority drilling based on their potential production rates.
A well with smaller-diameter pay string has been designed to reduce construction costs and make the involvement of unworked areas more efficient.
Pilot project starts in June 2019 on Vyngapurovskoe BV8/1 target to drill the first three small-diameter in-fill wells from well cluster No. A. Should the pilot be successful, the technology roll-out on first-train wells only will enable us involve over 8.1 million tons of recoverable oil reserves into development.