bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Hydraulic Fracture Propagation and Production Simulation Technology for Multi-Stage Optimization - A Case Study from Unconventional Reservoir
Authors: Zhang Jie , Lian Liming , Wang Peng , Li Guohui , Liu Zhiliang , Zou Guopeng , Tian Lei , Huang Xingning
Published: April 2024

Hydraulic fracturing technology, as an effective means to increase single well production, has been widely used in the production of various types of oil and gas reservoirs, achieving significant production enhancement. However, the heterogeneity of reservoirs determines that different reservoirs with different characteristics require different fracturing parameters. Using the same construction parameters for different reservoirs may increase operational costs and have adverse effects on production. In order to accurately obtain the optimal fracturing scheme, this study focuses on the following four aspects: 1) Regional geological research to accurately characterize the geological features of the reservoir; 2) Simulation research on the three-dimensional propagation of artificial fractures to visualize the artificial fracture network formed by different construction scales in three-dimensional space; 3) Numerical simulation research on productivity, combining the results of fracturing simulation to predict post-fracturing productivity; 4) Comparison and optimization of different fracturing schemes, considering factors such as fracturing construction cost, post-fracturing productivity, and effectiveness. The research results provide technical support for the design and optimization of fracturing schemes for production wells.
Steam Generation Using Renewables Energy - An Integrated Approach for Enhanced Oil Recovery Applications
Authors: Al Ajmi Mustafa , Al Lawati Abbas , Al Mayasi Arwa , Al Siyabi Idris , Al Lawati Mohammed , Al Harthi Shaikha , Al Hashmi Hamed
Published: April 2024

Petroleum Development Oman aspires to utilize the available renewable energy resources to produce steam for the Enhanced Oil Recovery operation in Amal oil field. The aim is to reduce the greenhouse gasses emitted from the current conventional steam production plants as well as reduce the dependency on natural gas for the process of generating steam. The paper also evaluates different types of renewable energy technologies against various value drivers in order to determine the optimum fit for purpose technologies that can be used for steam generation. In addition, it sheds light on the area selection process intended to host the proposed technologies. Finally, the paper discusses some of the operational challenges associated with the identified renewable energy technologies as well as states how such concepts can be further developed until realization.
Research and Pilot Experiment of Discontinuous Chemical Flooding Technology in Offshore Oilfield
Authors: Zhang Jian , Guan Cuo , Li Xianjie , Liang Dan , Zhao Wensen
Published: April 2024

Compared with conventional onshore oilfields, offshore oilfields have problems such as incomplete well pattern, large well spacing, strong heterogeneity, and high crude oil viscosity. Conventional chemical flooding methods have limited ability to control and drive, and relying on a single chemical agent system cannot avoid fingering and channeling in the presence of dominant pores and fractures. In order to continuously and evenly development the reservoir, it is necessary to study the discontinuous chemical flooding technology with the purposeful alternate combination of multiple chemical systems as the core. Firstly, the static properties and flooding characteristics of chemicals such as gels, microgels and associative polymers commonly used in discontinuous chemical flooding in offshore oilfields are evaluated. The concept of reservoir displacement equilibrium degree is established by comprehensively considering the sweeping conditions of every sub-layers and the oil displacement effect of the sub-layers. Based on this, combined with the physical simulation experiment of parallel core flooding, a simulation study is carried out on the adaptability of discontinuous chemical flooding and the production status of sub-layers in the process of discontinuous chemical flooding. Finally, Combining the indoor physical simulation test results, a pilot experiment plan for discontinuous chemical flooding in offshore BZ oil field is formulated. The basic performance of the chemical system commonly used in conventional chemical flooding is obtained through the experiments, and the systems are divided into three levels: strong, medium and weak according to the adjustable flooding intensity, which provides necessary parameter support for the efficient use of the chemical in the process of discontinuous chemical flooding. Through physical simulation experiments, the design principles and application specifications for obtaining discontinuous chemical flooding equilibrium production are given, which can provide theoretical guidance for practical field applications. Since the discontinuous chemical flooding in BZ oil field, the effect of oil increase has been remarkable. The peak daily oil production of a single well has increased by 115%, and the maximum reduction of water cut is 15%, At the same time, the effective time is more than five months. Discontinuous chemical flooding in offshore oilfields is a new development method that combines multiple technologies to "relay" flooding. This technology can efficiently improve oil production speed and oil production effect in the whole process of oilfield development, greatly shorten oilfield development time, in the shortest time to obtain maximum yield and economic benefits.
Enhanced Deep-Resistivity Measurement and High-Resolution Multilayer Inversions Improve Geosteering and Reservoir Mapping Performance Offshore UAE
Authors: Bourgeois Daniel , Suleiman Sameh Yahyia Ali , Siddiqui Wamiq , Burnely Syed Hammad Ali , Bautista Ramiro Oswaldo Vasquez , van Vliet Francois , Braganza Reinhard , Goddyn Xavier , Moreira Luis , D’Cruz Melroy
Published: April 2024

Dubai Petroleum Establishment (DPE) has been developing a field offshore UAE using directional drilling and logging-while-drilling measurement services. Multiple horizontal wells are being drilled to develop this field, and due to the thickness and complexity of the target reservoir, the wells are being geosteered with deep-directional resistivity measurements to map the target boundaries. While successfully drilling these wells while remaining in the target, the previous generation of measurements did not enable mapping of the target top over the entire section. In 2023, a new deep- directional propagation resistivity tool was introduced to improve geosteering decision making while drilling horizontal development wells.

Although deep and ultradeep propagation resistivity measurements from various tool configurations have been used for geosteering and reservoir boundary mapping for several years, the resistivity inversion is challenged as reservoir complexity and distance to boundary increase. The new technology introduces deep, calibrated resistivity measurement from a tilted antenna at farther spacing than typical resistivity measurements. This provides the deeper depth of investigation required to map the top of the target in this formation. In addition, deterministic inversions have been applied to the measurements, in contrast to the Monte Carlo-type inversion used in previous generations of deep- directional resistivity measurements. Deterministic-based inversions have shown better resolution when deployed for ultradeep propagation resistivity tools that use a wider spectrum of measurement spacing and frequency but have not previously been used for deep-resistivity tools.

The introduction of this technology improved the depth of investigation for mapping reservoir boundaries in this field and target intervals by 80%, allowing for earlier and more efficient decision making, which resulted in a smoother wellbore with fewer undulations. The target formation drilled with this new technology has several thin, clinoform features, dipping at a high angle relative to the overall formation dip. Using the high-resolution multilayer inversion with these deeper measurements, these clinoform features could be mapped, providing a better overall understanding of the reservoir.

The introduction of enhanced deep resistivity measurements and a high-resolution inversion allowed for improved geosteering and reservoir understanding to develop this offshore field.
Study on a Novel Comprehensive Numerical Simulation Model of Self-Generating Acid Fracturing for Ultra-Deep Carbonate Reservoir in the Shunbei Oilfield
Authors: Ren Jichuan. , Xu Peixuan. , Guo Jianchun. , Zhao Bing , Xie Xinjie , He Le , Gou Bo
Published: April 2024

China's continental marine carbonate rocks are rich in oil and gas resources, but the reservoir conditions are poor. Acid fracturing is the main technological measure for the stimulation of carbonate reservoirs at home and abroad. Due to the high temperature of carbonate reservoirs in China, the acid-rock reaction speed of gelled acid and other commonly used acid systems in the field is fast, so that the effective distance of acid is short (50-70m), the acid etched fracture conductivity at the distal end of the fracture is low, and the deep penetration transformation cannot be realized, which has a great influence on the stimulation effect of the reservoir. In this paper, a numerical model that can accurately describe the whole process of self-generating acid reaction under in-situ conditions is established. At the same time, fracture propagation, flow field, temperature field, concentration field and reaction process are coupled. The simulation analysis of self-generating acid concentration distribution, etching characteristics and effective acid etching fracture length under different influencing factors is carried out to understand the self-generating acid, etching law and main control factors, which provides a basis for the optimization design of self-generating acid fracturing process. The results show that (1) Temperature is the main factor affecting the acid generation rate of self-generating acid. The effective acid etching length at the distal end increases with the increase of temperature, the effective acid etching length at the proximal end decreases with the increase of temperature, and the overall effective acid etching length increases. Under the condition of 10 mD permeability, high displacement plays a role in promoting the effective acid etching fracture length, (2)The higher the matrix permeability, the smaller the effective acid etching fracture length.(3)Under the condition of small acid amount (300 m3) and medium acid amount (500 m3), the displacement has little effect on the effective etching fracture length. Under the condition of large acid amount (800 m3), the displacement has a certain promoting effect on the distal effective etching fracture length. (4)The greater the amount of acid injection, the greater the distal effective acid etching fracture length.
Best Practices to Predict and Recognize Liquid Loading and to Forecast and Maximize Intermittent Production
Authors: Veeken C. A.
Published: April 2024

Eventually, mature gas wells start liquid loading as their gas rate declines due to reservoir pressure depletion. That triggers a period of intermittent production until stable production can be restored by deliquification. This paper describes how to predict and recognize the onset of liquid loading, and how to forecast and optimize the associated intermittent production. These best practices can be used to minimize liquid loading deferment and to schedule deliquification measures.
Practical Appraisal of Sulfonated Polymers for a Sour High Salinity and Heavy Oil Reservoir in Kuwait to Fast-Track Field Implementation
Authors: Al-Murayri M. T. , Hassan A. , Alajmi N. , Andrianov A. , Garcia J. , de Kruijf A. , Liu E. , Li E.
Published: April 2024

Using high-salinity effluent water for polymer flooding is a strategic endeavor to mitigate water-handling constraints and debottleneck oil production. This study sheds light on the workflow that was adopted to select appropriate polyacrylamides with AMPS/ATBS monomers to improve polymer stability, particularly under harsh salinity, hardness and H2S levels. Molecular weight optimization was important to rationalize polymer selection for two stacked reservoirs with different permeabilities to reduce polymer retention and maximize oil gains.

Extensive laboratory evaluation followed by a one-spot EOR pilot and a regular 5-spot pattern confirmed the effectiveness of polymer flooding for the Umm Niqa Lower Fars (UNLF) sour heavy oil reservoir, using high-salinity effluent water with Polymer A, mainly targeting the F2 layer. This instigated further investigation on the feasibility of polymer-flooding for the UNLF F1 layer (i.e. F1), overlying the UNLF F2 layer (i.e. F2), using the same wells, configuration, inlet water and surface facilities. Two new polymers with different molecular weights, but similar chemistry to that of Polymer A were lab-evaluated on a fast-track basis covering rheology, injectivity, oil recovery, polymer retention, resistance factor, residual resistance factor and polymer stability.

F1 has higher oil viscosity, lower permeability and shallower depth compared to F2. This necessitates optimizing polymer molecular weight and concentration to establish good injectivity, optimize polymer concentration and reduce polymer retention. Following F2 field implementation using polyacrylamide Polymer A, two lower molecular weight polymers were identified for F1. Laboratory results using high-salinity effluent water and reservoir temperature showed that polyacrylamide Polymer B is better-suited for F1. This was evident from polymer retention and injectivity data. The optimal polymer concentration for field implementation has been defined using reservoir simulation to ensure commercial throughput and maximize oil gains, while safeguarding caprock integrity.

Polymer-flooding is time-sensitive and the incremental benefits of it tend to diminish with time. This study demonstrates the feasibility of fast-tracking laboratory evaluation to select appropriate polymers for expeditious field implementation. Future work can focus on further optimization of ATBS/AMS content, polymer concentration, water treatment requirements, and well completion to concurrently target multiple reservoir layers with reduced surface footprint.
Production Strategy for Gas Cap-Oil Rim-Water Drive Reservoirs: A Case Study of the N Field, Mehsana Asset, India
Authors: Parth C , Hitisha D , Moatoshi A. O. , Sanket T , Dayal H. S.
Published: April 2024

This technical paper presents a production approach implemented in the N field, where a reservoir characterized by a gas cap, oil rim, and water drive posed unique challenges for efficient recovery. Typically, conventional reservoirs employ perforation in the oil zone to facilitate pressure maintenance through gas cap expansion and the water drive mechanism. However, in the case of the N field, production from gas cap resulted in movement of oil in the gas zone. Instead of traditional perforation techniques, the reservoir was produced through targeted extraction of the gas cap. This approach outlines the operational procedures employed, highlighting the significant oil production rates after substantial gas extraction and movement of oil in the gas zone with the geological interpretations. There are three layers in this area, K-I, K-II and K-III. K-III is majorly oil bearing while K-II has a thick oil rim and K-I has thin oil rim and major gas cap area. The well wise execution strategy of K-III, II and I have been explained in the paper. This production strategy led to reservoir management via chemical water-shut off jobs, production logging-based perforation optimization and liquid rate optimization.

Following this unconventional step, the oil migrated to the anticlinal top structure of the reservoir, enabling subsequent production of oil after production of gas cap gas and till now it has yielded recovery rates of greater than 40% with current oil production of 860 tpd. The findings of this study emphasize the importance of considering unconventional production strategies tailored to specific reservoir characteristics. The case of the N field demonstrates the potential for achieving improved recovery rates and optimizing the utilization of available resources in gas cap-oil rim-water drive reservoirs. The insights gained from this unconventional approach can contribute to the development of future production techniques in similar reservoir types, ultimately enhancing oil recovery and overall field performance.
Advanced Carbonate Acidizing with Optimized Retarded Acid to Reduce Matrix Acidizing Carbon Footprint
Authors: Ryan A. , Kamaletdinov B. , Araque G. , Arali V.
Published: April 2024

In pursuit of the 1.5°C climate threshold set by the Paris agreement above pre-industrial levels, achieving net-zero CO2 emissions by 2050 is identified as crucial. This necessitates leadership from the energy industries in formulating and executing sustainability development goals. Addressing all emissions sources is imperative for the success of this ambitious endeavor. The study investigates the application of an optimized dosage of a novel single-phase retarded acid (SPRA) fluid system to reduce the carbon footprint in stimulating horizontal extended reach wells targeting lower-permeability reservoirs in Middle East.

Hydrochloric acid (HCl), which is commonly employed in matrix acidizing for creating wormholes in carbonate reservoirs, faces challenges in achieving the desired productivity index due to rapid reactions at high bottomhole static temperatures. The development of SPRA, an HCl-based fluid with enhanced retardation factor, demonstrated superior wormhole penetration depth through the synergistic action of two retarding agents. Employing stimulation modeling analysis, this work investigated optimized SPRA dosage and demonstrated its superior performance over regular HCl acid in post-stimulation skin reduction and wormhole generation. In most of the SPRA applications, the performance of the stimulation treatment is still higher compared to the straight acid, even at reduced volume. Subsequent history matching exercises confirmed the generation of longer wormholes and the effective reduction of skin across the entire lateral section of the well.

Validation of simulation findings was achieved through flowback and production data collected after stimulation. The presented case studies demonstrate the implementation of the innovative SPRA fluid system, resulting in a significant reduction of up to 51%, equivalent to 274 metric tons of CO2 emissions throughout the entire value chain. This includes a 50% reduction in total acid volume and a substantial 67% decrease in flowback time. These findings underscore the considerable environmental and operational benefits of the SPRA fluid system in advanced carbonate acidizing of extended reach wells.
Novel Nanoparticles Based Stimulation Fluid Enhances Productivity in High Temperature Gas Reservoirs
Authors: Kalgaonkar Rajendra A. , Sahu Qasim A. , Malik Ataur R. , Ghazwi Mustafa A.
Published: April 2024

Emulsified acids are conventionally utilized in acid fracturing operations in tight gas reservoirs. Unfortunately, the thermal stability of the emulsified acids is significantly impacted at high temperatures (> 300 °F), which will result in poor penetration of the reservoir, thus reducing the treatment effectiveness. Moreover, high viscosity of conventional emulsified acids often results in high friction losses limiting the pumping rate in acid fracturing treatments.

In this paper we demonstrate the development and successful field applications of enhanced acid emulsion system that incorporates surface modified nanoparticles. The unique morphology of the nanoparticles along with their selective organic modification facilitates formation of a high temperature stable acid system with lower viscosity compared to conventional emulsified acids. The fluid exhibited reduced pumping pressures leading to higher pumping rates for deeper penetration in multistage horizontal wells. The new system can work with HCl concentration up to 28% and temperatures up to 325 °F.

We present here the systematic developmental study and field trial results for the nanoparticles stabilized emulsified acid system, targeting high temperature carbonate gas reservoirs in multistage horizontal wells. Several laboratory performance tests were judiciously undertaken to compare the performance of the new emulsified acid with conventional systems. Experimental studies including rheological characterization, thermal stability, corrosion mitigation and reservoir damage profiling are reported. The new emulsified acid displayed lower viscosity, enhanced stability at high temperatures, corrosion loss within industry acceptable limits, superior stimulation effectiveness and minimal formation damage compared to conventional emulsified acid. The stimulation operation utilizing the enhanced acid emulsion showcased excellent flowback performance without indication of any formation damage.

The novelty of this paper is the development of the enhanced emulsified acid stabilized with the surface modified nanoparticles having a unique morphology. The main advantages of this enhanced acid system were its high temperature stability and lower friction pressure pressures facilitating higher pumping rates and maintaining continuous net pressure, thus, deeper reservoir penetration resulting in excellent stimulation of carbonate reservoirs.
Optimizing Underbalanced Coiled Tubing Drilling Monitoring Via Advanced In-Line Sensing AI Framework
Authors: Abu Alsaud S. , Katterbaue K. , Alshehri A.
Published: April 2024

Logging while drilling (LWD) technologies have been extensively developed and implemented to evaluate downhole rock and fluid properties. Nevertheless, sparsity of information, indirect measurements, and a challenging downhole environment are critical factors in obtaining accurate formation evaluation diagnostics. This is especially critical given the limited number of LWD technologies for underbalanced coiled tubing drilling (UBCTD). As such, forecasting formation patterns and drilling conditions from real-time surface in-line measurements on the return mud is a promising area that will significantly advance UBCTD monitoring capabilities. In this work, we present a noninvasive data driven approach by utilizing a series of inline sensors on the mud return to determine the characterization of fluids and rock cuttings. An advanced nonlinear autoregressive network was utilized for the forecasting of the solid and hydrocarbon concentrations based on the sensor derived in-pipe measurements. The measuring sensors comprise a range of inline sensors, including ultrasonic acoustic sensors, optical imaging devices, pipe resistivity sensors, spectral gamma ray sensors, flow meters, and viscosity sensors. The results demonstrate the strong forecasting capabilities of the nonlinear autoregressive network deep learning framework in determining solid and hydrocarbon concentrations and may support classifying rock cutting' types in real-time based on the measurement dataset. The test was conducted on synthetically realistic formation drilling data, which showed strong estimation capabilities and a high-performance score. Based on the test, we concluded that gamma rays, electromagnetic induction, optical, and acoustic sensing are the major principal components affecting the quality of the estimation. This deep learning framework is instrumental in the integration of LWD, measurement while drilling (MWD), advanced mud logging, and drilling parameter data to guide UBCTD operations and support real-time formation evaluation.
A Chemical Method of Achieving Uniform Stimulation Intensity Along Long Laterals in Horizontal Wells
Authors: Zebo Yuan , Huifeng Liu , Ning Xu , Song Jin , Ying Shi , Zhangxin Chen
Published: April 2024

To exploit a reservoir more efficiently, horizontal wells with long laterals are being drilled in many oilfields in the world. Uniform acidizing by bullheading is a challenge in these wells because the volume of acid that enters each segment tends to be different: larger at the heel while smaller at the toe. This further causes a non-uniform production profile which advances breakthrough of water.

In this paper, a method of using a temperature-sensitive viscous acid to achieve uniform stimulation profile is introduced. The acid is delicately designed so that the viscosity of it changes with temperature and the changing rate can be quantitatively controlled. As the acid flows in wellbore, the diffusion coefficient of H+ and therefore the acid-rock reaction rate gradually increases while it is being warmed by wellbore. A model describing the change of viscosity and H+ mass transfer coefficient is established and coupled with a wellbore heat transfer model.

The basic of this acid is hydrochloric acid but it is mixed with a special gelatinizer. The initial viscosity of the acid ranges from 60 to 1400 mPa.s at surface, depending on the concentration of gelatinizer. Its viscosity gradually decreases to 200 mPa.s with temperature increasing to 100 ℃.The leaking off velocity decreases from 2.0×10−6 m/s to 2.0×10−7 m/s accordingly, depending on the injecting time. And the acid concentration at the wall of wellbore increase by three times when the injecting rate doubles, also depending on the wellbore temperature and pressure. The acid-rock reaction rate is faster at toe than at heel, which just compensates the differences of acid volume allocation between toe and heel due to wellbore flow friction. A model describing the correlations between the acid viscosity, diffusion coefficient of H+, the concentrations of HCl, the injection rate and the temperature is generated. This model is coupled with an acid flow and reaction model and a wellbore heat transfer model and in the end a profile of H+ consumption along the lateral is predicted. With use of this model, by adjustment of acid formula and injection rate, a uniform stimulation intensity profile along the long lateral can be achieved. A well case is introduced to show the application of this model.

The dynamic temperature profile, the acid viscosity profile, the allocation of hydrogen ions as well as the equivalent wormhole lengths along the wellbore are all given in the paper. This paper introduces a chemical way to achieve uniform acidizing intensity in horizontal wells with long laterals without running in mechanical tools, reducing cost and leaving a good wellbore environment for future well interventions after treatment.
Determining Key Reservoir Parameters from Diagnostic Fracture Injection Test DFIT Conducted in a Disposal Well in the Bahrain Field Using Multiple Analysis Techniques
Authors: Konwar Lakshi , Bu Ali Y. Y. , Ali W. , Naira W. , Alawainati E. M. , Omar Matar
Published: April 2024

In the Bahrain field, wet sand waste/sludge mixtures generated from the Waste Management Sump Facility (WMSF) are stored in temporary storage areas. A well in a sandstone reservoir is identified for conversion to water disposal for waste management to dump around 3,000 barrels of NORM (naturally occurring radiative material) waste accumulated over the last 5 years. Estimating formation breakdown pressure and reservoir flow capacity is crucial for injection capacity estimation and safe injection in a disposal well. Step-rate test (SRT) and injection falloff have now become the standard practice to estimate formation breakdown pressure, reservoir pressure, and formation permeability. This paper focuses on the preparation of a NORM injector after a detailed review of geological, petrophysical, production, and reservoir engineering data of the sandstone reservoir in the field. An injectivity test using SRT followed by a pressure falloff test was conducted in the subject well to determine the injection rates and pressures required for injection of NORM waste. The paper presents the results of the step rate test (SRT) and both the before-closure and the after-closure analysis (ACA) of the falloff test conducted on the disposal well prior to design of SFI (slurry fracture injection process).

Besides conventional analysis, the SRT is analyzed using modified-Hall analysis (MDH) and injectivity analysis. In addition, two rate and multi-rate (injection) analysis methods are also used for unambiguous interpretation of the data. Both pressure-derivative and G-function analysis are used to analyze DFIT data in order to evaluate fracture-closure pressure. Other parameters obtained from ACA are instantaneous shut-in pressure (ISIP) and fracture efficiency. The log-log derivative plot confirms the presence of the late-time pseudo-radial flow regime. Pseudo-radial flow analysis by different methods are used to determine reservoir permeability and initial reservoir pressure.

Based on the analysis, it is inferred that reservoir is of good permeability as observed in high injection rates and corroborated by high permeability estimated from the radial-flow plot of ACA. The fracture breakdown pressures determined by conventional, two-rate and multi-rate analysis methods are supported by both modified-Hall and injectivity analysis. Fracture-closure pressure obtained from G-function, square-root, and derivative analyses compare favorably. Initial reservoir pressure and formation permeability estimated by different techniques are in good agreement, thus instilling confidence into the analysis.

The multiple techniques described here can be used for comprehensive and credible analysis of SRT as well as before-closure and after-closure analysis of falloff data in a disposal well
Innovative Reamer Stabiliser Technology Enhances Wellbore Stability and Creates Value by Reducing NPT, Improving Hole Quality, and Reducing Drilling Costs
Authors: Mehregan A. , Hassani V. , Brister R. , Rui X.
Published: April 2024

Value creation and cost reduction can be accomplished in many ways. Torque, drag, vibration, and Non-Productive time (NPT) all negatively impact total cost on drilling projects. Any efforts to create value by reducing these negative influences on a project’s metrics and overall cost are welcomed. Since most of those influences occur at the drill bit or BHA interface with the formation, that is one area where the focus on creating value and reducing cost occurs. Reamers, stabilizers, bits, gauge tools and hole opener tools are included in that technology focus area.

A new stabilizer reamer tool incorporating innovative technology has been introduced globally to address what existing conventional reamers and stabilizer reamers were failing to do with consistency across different formations. This tool’s primary focus is on wellbore stability and borehole quality. Additional benefits include controlling and reducing torque, drag, and vibration resulting in the biggest impact to reduction of NPT, days on well, casing point to casing point time, and consequently, total cost of a drilling project.

Ultimately, this paper details the design features and components of the new stabilizer reamer tool. Shaped TCI "donut" cutters, their patented placement structure, and fixed blade geometry, along with their design and placement work hand in hand to provide consistent positive metrics and increased value wherever applied. This paper also focuses on several tool applications around the world. Metrics were analysed and an optimized model of reamer placement in the BHA was generated. The case histories are presented where before/after data was analyzed, Lessons Learned registers were kept and moved from application to application, and subsequent design changes were proposed and incorporated.

The data show that managing torque, drag, and vibration while drilling using the new reamer tool, reduced the risk of stuck pipe, reduced trip times, increased borehole and caliper quality, and increased efficiencies for wireline, tubing, casing and liner, and completion runs. Consequently, the new reamer stabilizer tool definitively accomplished all value creation and NPT/cost reduction objectives in part due to the innovative cutter and blade shape, design, and placement.
Experimental Assessment of Time Dependent Wettability Alteration in CO2-Brine-Rock System
Authors: Alsalman Mahdi , Raza Arshad , Mahmoud Mohamed , Murtaza Mobeen , Arif Muhammad , Isah Abubakar , Alafnan Saad , Shahzad Kamal Muhammad
Published: April 2024

The subsurface processes of enhanced oil recovery (EOR) and carbon capture and storage (CCS) involve complex geochemical interactions mainly CO2, brine, and reservoir rock. This interaction is time-dependent and could influence the wettability and thus the multiphase flow. Less attention has been given to this interaction caused by a weak acidic environment to understand the wettability of CO2/brine/rock systems under high pressure and high temperature over time. This study aims to experimentally investigate the wettability of sandstone and carbonates in a CO2/brine environment at pressure levels between 0.1 to 10 MPa and at 50°C temperature. To this end, a 2-week time duration was considered for aging samples at 50 °C and 10 MPa, for contact angle measurements on theCO2/brine/rock system. The results indicate a significant contact angle shift from weakly water-wet to weakly CO2-wet as a result of geochemical interaction. Particularly, the change in contact angle in carbonates is much higher than the contact angle noticed in sandstone. In addition, there is an increase in contact angle with the pressure, which is consistent with the interfacial tension measurement. Interestingly, the retention of brine on the rock surface shows interesting results in the presence of CO2 – less in sandstone than more in carbonates. This research would help us better understand changes in wettability and thus develop more effective strategies for storage prospectives. In addition, more data is needed to acquire, so that predictive models can be designed to simulate and optimize fluid dynamics for CO2 injection and storage applications.
Real-Time Data Harvesting: A Confirmation of Fracture Geometry Development and Production Using Fiber Optic in Deep Tight Gas Wells
Authors: Aamri Ghusun Al , Al Bulushi Anam , Abelazim Mohamed , Kurniadi Stevanus Dwi , Al-Ghaiti Ali , Siddiqui Mohammed , Hassan Karim , Guzman Rafael Castiblanco , Mowad Benjamin , Alyahyaai Hamood
Published: April 2024

The understanding of close-to-reality fracture geometry and conductivity is needed to make decisions and drive the strategy of the hydraulic fracturing. In most cases, the pressure match is utilized even though it does not provide a unique solution. The acquisition of one or more fixed parameters, such as fracture height and length, from surveillance will enable a definition of hydraulic fracture geometry and conductivity that is close to reality.

Multiple height measurements such as those obtained by radioactive tracer have been implemented to provide post-fracturing height measurement surveillance. However, the tracer result does not provide real-time fracture propagation behavior. Real-time surveillance could enable making decisions for timely intervention treatment execution. Real-time intervention could avoid propagation of the fracture into unwanted zones and could minimize the risk of screenout due to height growth. Fiber-optic data collection is proposed as a real-time surveillance method.

Fiber-optic surveillance methods could help the decision-making process during hydraulic fracturing treatment and production evaluation in multiple-stage fracturing. In the application, the real-time data could trigger real-time intervention to minimize the impact of the screenout. During the post-treatment evaluation, understanding the screenout development process will enable devising a fit-for-purpose strategy for each formation in the next well. The real-time harvesting of data during post-fracturing production will make possible a qualitative understanding of the zone contributions and behavior of each stage at any time of the well life and will provide insight for the field development plan.

This work introduces a surveillance strategy optimization approach that will be able to provide understanding of the fracture geometry and zonal contribution through real-time measurement until the end of the well life. It also provides insight into the use of real-time data acquisition to understand the fracture and the production behavior and recommendations based on fiber-optic surveillance deployment.
Experimental Investigation of CO2 Storage Parameters for Deep Saline Aquifers
Authors: Penigin A. , Ivanova A. , Grishin P. , Bakulin D. , Yunusov T. , Morkovkin A. , Cheremisin A.
Published: April 2024

The storage of CO2 is controlled by a variety of parameters. While it is impossible to quantify or predict their distribution across the inter-well space their accurate measurement in known points (wells and core) are obviously beneficial for making more accurate forecasts. While all the requirements for storage characterization are stated clearly in guiding documents (as in ISO 27914 or DNV RP-J203) and national regulations and codes the specifics as to how to approach lab studies are not included. Therefore, in order to ensure the safety and operational capability of a CO2 storage project a part of lab studies design is proposed with corresponding results and their interpretation. Since the main goal of these projects is to reduce greenhouse gases emission to alleviate climate change and consequently they are bound to be verified across the world an attempt to come to universally accepted approach seems justified and necessary.

CO2 storage is influenced by various parameters, which are difficult to quantify or predict in the inter-well space. However, their precise measurement in known locations (such as wells and core samples) can enhance the accuracy of storage forecasts. Although the general requirements for storage characterization are clearly defined in guidance documents (e.g., ISO 27914 or DNV RP-J203) and national regulations and standards, the specific methods for conducting laboratory studies are not specified. Therefore, this paper proposes a partial design of laboratory studies for a CO2 storage project, along with the results and their interpretation. The main objective of these projects is to mitigate climate change by reducing greenhouse gas emissions, which requires global verification. Hence, developing a universally accepted approach is both reasonable and necessary.
Reconfigurable Two-dimensional Floating Gate Field-effect Transistors for Highly Integrated In-memory Computing
Authors: Lee Gwan-Hyoung , Hwang Cheol Seong , Shin June-Chul , Park Taegyun , Shin Dong Hoon , Choi Hyun-Young , Watanabe Kenji , Taniguchi Takashi , Jung Yeonwoong
Published: April 2024

With the increasing need for highly integrable and energy-efficient hardware for cutting-edge applications, such as neuromorphic and in-memory computing, reconfigurable devices with multi-functional operations are essential for these applications, enhancing performance and area efficiency. However, traditional reconfigurable devices suffer from limited functionality and circuit incompatibility due to the adoption of multiple gates, leading to increased system complexity and manufacturing costs. This work demonstrates reconfigurable floating-gate field-effect transistors (R-FGFETs) based on van der Waals (vdW) heterostructure to implement highly integrable and reconfigurable circuits for in-memory computing with minimum overhead. By modulating the charge trapping within the graphene floating gate using a single gate terminal, R-FGFETs can attain four distinct electrical conducting states: metallic, n- and p-type semiconducting, and insulating. By incorporating these R-FGFETs into reconfigurable combinatorial computing units, programmable logic and arithmetic operations, including 16 Boolean logic gates, addition, subtraction, and comparison, are feasibly achieved with minimal overhead. Also, a novel method is proposed to address voltage mismatch between input and output through programming voltage-dependent threshold voltage shift, facilitating efficient connections between logic gates. This work offers a potential pathway for highly integrating a reconfigurable processor based on vdW heterostructures, thus providing an area- and energy-efficient solution.
Enhanced Osteogenesis of Mesenchymal Stem Cells Encapsulated in Injectable Microporous Hydrogel
Authors: Edwards Seth D. , Ganash Mrinal , Guan Ziqiang , Lee Jeil , Kim Young Jo , Jeong Kyung Jae
Published: April 2024

Delivery of therapeutic stem cells to treat bone tissue damage is a promising strategy that faces many hurdles to clinical translation. Among them is the design of a delivery vehicle which promotes desired cell behavior for new bone formation. In this work, we describe the use of an injectable microporous hydrogel, made of crosslinked gelatin microgels, for the encapsulation and delivery of human mesenchymal stem cells (MSCs) and compared it to a traditional nonporous injectable hydrogel. MSCs encapsulated in the microporous hydrogel showed rapid cell spreading with direct cell-cell connections whereas the MSCs in the nonporous hydrogel were entrapped by the surrounding polymer mesh and isolated from each other. Microporous hydrogel induced more robust osteogenic differentiation of MSCs and calcium mineral deposition than the nonporous hydrogel confirmed by alkaline phosphatase (ALP) assay and calcium assay. RNA-seq confirmed the upregulation of the genes and pathways that are associated with cell spreading and cell-cell connections, as well as the osteogenesis in the microporous hydrogel. These results demonstrate that the microgel-based injectable hydrogels can be useful tools for therapeutic cell delivery for bone tissue repair.
PSA Doubling Time 4.65 months as an Optimal Cut-off of Japanese Nonmetastatic Castration-Resistant Prostate Cancer: Multi-institutional Study of Japanese Urological Oncology Group (JUOG)
Authors: Sakamoto Shinichi , Sato Kodai , Kimura Takahiro , Matsui Yoshiyuki , Shiraishi Yusuke , Hashimoto Kohei , Miyake Hideaki , Narita Shintaro , Miki Jun , Matsumoto Ryuji , Kato Takuma , Saito Toshihiro , Tomida Ryotaro , Shiota Masaki , Akira Joraku , Terada Naoki , Shigetaka Suekane , Kaneko Tomoyuki , Tatarano Shuichi , Nishiyama Naotaka , Kawakami Eiryo , Ichikawa Tomohiko , Kitamura Hiroshi , Yoshio Yuko , Yoshino Takayuki
Published: April 2024

A multicenter study of nonmetastatic castration-resistant prostate cancer (nmCRPC) was conducted to examine the prognostic to identify the optimal cut-off value of prostate-specific antigen (PSA) doubling time (PSADT) in Japanese nmCRPC. Of the 515 patients diagnosed and treated for nmCRPC at 25 participating Japanese Urological Oncology Group centers, 450 patients with complete clinical information were included. The prognostic values of clinical factors were evaluated with respect to prostate specific antigen progression-free (PFS), cancer-specific survival (CSS), and overall survival (OS). The optimal cutoff value of PSADT was identified using survival tree analysis by Python. The Median PSA and PSADT at diagnosis of nmCRPC were 3.3 ng/ml, and 5.2 months, respectively. Patients treated with novel hormonal therapy (NHT) showed significantly longer PFS (HR: Hazard Ratio 0.38, p < .0001) and PFS2 (HR 0.45, p < .0001) than those treated with vintage nonsteroidal antiandrogen agent (Vintage). The survival tree identified 4.65 months as the most prognostic PSADT cutoff point. Among the clinical and pathological factors PSADT of < 4.65 months remained an independent prognostic factor for OS (HR 2.96, p = .0003) and CSS (HR 3.66, p < .0001). Current data represented optimal cut-off of PSADT 4.65 months for a Japanese nmCRPC.
The Computerized Algorithm for Renal Assessment Improves Diagnostic Accuracy of Renal Impairment in Hospitalized Patients
Authors: Chen Chun-You , Chang Te-I , Chen Cheng-Hsien , Hsu Shih-Chang , Chu Yen-Ling , Huang Nai-Jen , Sue Yuh-Mou , Chen Tso-Hsiao , Huang Po-Hsun , Liu Chung-Te , Hsieh Hui-Ling
Published: April 2024

Background: Acute kidney injury (AKI) is an important adverse event of hospitalized patients that associates high mortality and high medical cost. While accurate diagnosis and timely management of AKI is essential for improving the outcomes of in-hospital AKI, delayed diagnosis or misdiagnosis by clinicians hinders the advance in the care of AKI. To ameliorate this problem, several electronic AKI alert systems had been proposed, which had shown inconsistent effects on the outcomes of AKI. Before electronic systems could improve the outcomes of AKI, an important issue to be elucidated is to confirm their diagnostic accuracy. The purpose of the present study is to establish an easy-to-construct Computerized Algorithm for the diagnosis of renal impairment and to test its accuracy.
Methods: The present study retrospectively included 1551 hospitalized patients with serum creatinine (SCr) of > 1.3 mg/dL in Wanfang Hospital. A Computerized Algorithm was constructed to identify AKI events and CKD cases among these patients. Previous SCr tests were reviewed to define the baseline SCr level. Increased SCr level of > 1.5 times from baseline was defined as AKI. Estimated glomerular filtration rate (eGFR) of < 60 mL/min/1.73m2 for > 90 days was defined as CKD. The standard diagnoses were made by experienced nephrologists according to the same criteria. The discharge diagnoses made by the attending physician was defined as clinician’s diagnoses. The diagnoses made by Computerized Algorithm and the clinicians were compared with the researcher’s diagnoses to define their accuracy.
Results: Of the included patients, the mean age was 73.0 years old; the in-hospital mortality was 14.8%; AKI was present in 28.6% of the patients. Regarding the diagnostic accuracy for AKI, the Computerized Algorithm achieved a sensitivity of 85.6% and a specificity of 98.8%. The main cause of false negative (FN) AKI diagnosis was that AKI occurred earlier than the outpatient visiting before the indexed hospitalization. Regarding the diagnostic accuracy for CKD, the Computerized Algorithm achieved a sensitivity of 94.7% and a specificity of 100%. The cause of FN CKD diagnosis was exclusively lack of previous eGFR records. Compared to the clinician’s diagnoses, the Computerized Algorithm exhibited significantly superior accuracy than the clinician’s diagnoses in both AKI (95.0% versus 57.0%) and CKD (96.5% versus 73.6%).
Conclusions: We developed a simple and easy-to-construct Computerized Algorithm for the diagnosis of renal impairment, which significantly improved the diagnostic accuracy of AKI and CKD than clinicians did. In future, an algorithmic approach for differential diagnosis of AKI and decision guide with be incorporated into this system.