bluuebunny/crossref_metadata_2025 huggingface dataset:
Identifying and Unlocking Hydrocarbon Potential in Cretaceous Sandstones With High-Density Calcareous Concretions in Rondon-Terecay Area, Arauca, Colombia
Authors: Solano A. A. , Layton R. M. , Ataya C. D. , Chavarro N. A. , Hernandez A.
Published: November 2024

This paper endeavors to present the potential and development strategy for the K2C reservoir, characterized by low-resistivity sandstones interbedded with high-resistivity calcareous concretions. These features represent a reservoir characterization challenge due to the lack of logs response and the difficulty to quantify the oil volume storage by the sandstones in the calcareous zones. The study employed a comprehensive sedimentological analysis to delineate the geometry and architecture of the K2C reservoir in the Rondon area, integrating various data sources such as cores, logs, cuttings, and petrography. The selection of wells for workovers, based on integrated data, yielded favorable results, affirming the reservoir concept and prompting expansion in Rondon- Terecay and other Llano’s areas. The 2023/2024 workover campaign in Rondon yielded an average production of 1100 barrels of oil per day (BOPD) with an 80% water cut, validating the natural productivity of the reservoir without chemical or mechanical treatments. This success unveiled substantial reserves increase of 56%, for future development, with projected production peaks of 2000 BOPD by the end of 2024 and 2400 BOPD in 2026. The study also underscores untapped opportunities in northern fields, notably in Cravo Norte, indicating significant additional hydrocarbon potential. By validating the reservoir concept in calcareous sandstones with high-density calcareous concretions in Rondon- Terecay, this paper offers a novel perspective, providing valuable insights for practicing geologist and engineers to identify and develop analogous reservoirs, thereby enhancing their management and understanding of hydrocarbon assets.
Navigating the Talent Shift and Building the Digital Workforce of Tomorrow – PDO Case Study
Authors: Al Abri. H.
Published: November 2024

The oil and gas industry is undergoing a significant transformation, driven by the need for greater efficiency, sustainability, and technological advancements. This transition requires a fundamental shift in the workforce, with a growing demand for digital skills and a new generation of talent. In this paper, we present a case study of Petroleum Development Oman's (PDO) initiative to navigate this talent shift and build the digital workforce of tomorrow.

The paper begins by examining the key drivers behind the industry's digital transformation, including the evolving energy landscape, the rise of automation and data-driven decision-making, and the changing expectations of the workforce. It then delves into PDO's strategic approach to address these challenges, highlighting the company's focused efforts to upskill its existing workforce, attract and retain top digital talent, and foster a culture of innovation and continuous learning.

The core of the manuscript details PDO's multifaceted talent development program, which comprises comprehensive training, targeted recruitment, and strategic partnerships. The program encompasses initiatives such as digital academies, online learning platforms, and collaboration with academia and technology providers to ensure that the workforce is equipped with the necessary skills to thrive in the digital era.

The paper also discusses the tangible results and impact of PDO's talent development initiatives, showcasing improved operational efficiency, enhanced decision-making capabilities, and the successful integration of emerging technologies across the organization. Finally, it explores the lessons learned and the key considerations for other oil and gas companies seeking to navigate the talent shift and build a future-ready digital workforce.
An Innovative Approach to the Selection of Critical Design Parameters Influencing Sand Control Efficacy in Standalone Sand Screens Deployed in Oil and Gas Wells
Authors: Razak R. , Alosail M. S. , Musa K. I. , Gago P. A. , Chen Z. , Tyson S. , Rahman S. S.
Published: November 2024

The objective of screen testing and selection is to minimise sand production while maintaining acceptable filter permeability, however, screen failures during operation are common and difficult or expensive to fix. Our research improves current selection tests and considers the expected time to failure for the screen. Experimental tests for screen selection compare retained permeability and produced solids for different screen apertures and weave types. Our study suggests that performance is only minimally dependent on aperture and weave, but more strongly dependent on the structure of the filter-bed that builds up on the screen. We also show that screen failures are directly linked to the structure of the deposited filter-bed. The aim of our work is to develop a relationship between filter bed packing, filter bed thickness, and screen stresses, to introduce preliminary quantification of the required strength of a screen and extend its operating life.

Our methodology uses a CFD-DEM model to simulate four common screen types. The numerical model is calibrated using an innovative laboratory experimental result and the corresponding micro-CT image of the deposited filter-bed at, using sand samples from wells offshore Brunei. The metric used for calibration is the single-phase permeability parameter.

The retained permeability and the rate of sand production is only weakly dependent on the weave and aperture of screen coupons in both experimental tests and numerical simulations. The behaviour of the screen is better correlated with the structure and composition of the filter-bed. Numerical simulations of behaviour of the screen and the filter-bed allowed us to analyse the stress on the screen, which is not normally measured in experimental screen retention tests. As the filter-bed is a granular media, the forces transmitted through the filter-bed are spatially highly variable with some locations on the screen receiving extremely high point forces which are above the manufacturers specified collapse pressure. Our advanced numerical method that involves stress analyses on sand screens allows us to develop a more comprehensive set of criteria for screen selection which should reduce the occurrence of screen failure or extended the expected time to failure.

The novelty of this research is the development of new techniques to investigate the screens’ ability to resist collapse due to non-uniform forces on the screen. During this research, it also became apparent that screens with different weaves and apertures perform broadly the same in terms of produced sand and retained permeability. As a result of these observations, we suggest a more rigorous comparative test that considers the expected life of the screen and its susceptibility to failure.
Unconventional Scale Inhibition and Acid Stimulation Strategies for Enhanced Oil Recovery in Sandstone Formations: A Case Study from Southern Oman
Authors: Shukaili Ghosin Al , Ruqaishi Moza Al , Kalbani Muhannad Al , Riyami Yaqoob Al , Amri Ibrahim Al , Habsi Al Moatasem Al , Lawati Ahmed Al , Jabri Dawood Al , Hatmi Safiya Al , Shabibi Ali Al
Published: November 2024

Field X is an oil field characterized by sandstone formations, discovered in 1984 and put into production in 1987. Waterflooding has been integrated into field development plan since 2007 to enhance oil recovery. One of the main challenges in Field X is the underperformance of the water flood system, which led to a severe oil production decline, 30% below target by the end of 2022.

The water injector wells suffer from significant scale deposition over time caused by water incompatibilities and pressure/temperature changes. Even though measures such as applying downstream scale inhibitors and performing acid stimulation have been in practice since 2010 to tackle the problem, the severity of scale deposition remains severe.

A comprehensive review on previous scale formation prediction studies has been done, along with taking downhole samples to identify main scale elements in place. Four different lab analysis have been conducted including solubility tests, XRD, XRF, and bulk scale analysis (BSA). Lab analysis from the downhole scale samples showed up to 60% of samples are insoluble in HCL acid, in which two dominant scale types were identified CaCO3 and CaSO4.

Assessment of the current field inhibition strategy to survey and quality assure different aspects, such as the applied scale inhibitor type, dosage, and skid locations. Three different scale inhibitors were tested at both surface and downhole conditions to identify the optimum candidate. Testing has shown an increase in dosage from 15-20 ppm to 30 ppm.

Due to the presence of HCl insoluble mineral deposits, the old acid treatment recipe was found inadequate and only provided temporary solutions. Based on Laboratory results using mineralogy data from analogous wells, mud acid (9%Hydrochloric acid-1%Hydroflouric acid) was proposed for stimulating poorly performing injectors in field X. Trail camping was done using new acid treatment strategy.

As a result of these efforts, Field X’s injection has improved by 73% compared to 2022. This has led to an improvement in overall field production by 27%. Additionally, there has been a decrease in total suspended solids (TSS) when compared to previous years.

This paper investigates the effectiveness of non-traditional acid and solvent systems in sandstone formations in Southern Oman for healthier waterflood management.
Enhanced 9.625-Inches Cementing Practices Proved the Best Well Integrity Solutions and Eliminates the 7-InchesTieback Options in Onshore Oil Field in the United Arab Emirates
Authors: Valencerina Lou , Ahmad Mushtaq , Reyami Mazin Al , AlShehhi Mouza , Khan Faisal Gul , Felaza Fesarama , Ameh Ugbedeojo
Published: November 2024

Conventional drilling methods in UAE onshore oil fields have faced significant challenges, including wellbore instability and fluid losses across aquifers during the drilling of 12.25-inch intermediate hole sections. These challenges impacted drilling productivity and compromise well integrity, particularly during the cementing of 9.625-incheds casing strings. The conventional practice of using repeated cement/sodium silicate plugs to address these issues has proven insufficient, often necessitating the use of a 7-inch casing tieback to ensure well integrity throughout the well’s lifecycle. This paper presents enhanced 9 5/8-inch cementing practices designed to eliminate the need for a 7-inch tieback while preserving the option for future side tracking. The adoption of these enhanced practices has led to significant cost savings, reduced well durations, and improved well integrity. By detailing the methodology, results, and implications, this paper provides valuable insights into modern cementing practices and their impact on drilling efficiency and cost management.
Enhancing Electrical Submersible Pump Operations: Leveraging Data-Driven Models Using Advanced Machine Learning and IoT Technologies for Effective Event Management
Authors: Al Mansoori Yousof , Al Shamsi Mohamed K. , Lotfy M. , Cardozo J. , Alzurba R. , Rivadeneira I. , Bougherira Y. , Akrouti Issam , Tawakol M. , Fidler E. , Lenicky M. , Wahba S.
Published: November 2024

Electrical Submersible Pumps (ESPs) are widely used in the petroleum industry as an effective artificial lift method. ESP pumps are particularly effective in scenarios with reservoirs having low bottomhole pressure, low gas/oil ratio, high water cut, and low API gravity fluids. However, ESPs are very susceptible to issues depending on the well and reservoir conditions, requiring continuous monitoring and analysis of performance and failures of the ESP system. Despite their widespread application, operating ESP wells presents several challenges that can impact efficiency, reliability, and overall operational costs. Common issues include sand and solids production, gas interference, corrosion and scale formation, power supply inconsistencies, high reservoir temperatures, handling of viscous fluids, complications in deep and deviated wells, and mechanical failures due to vibration and stress. Addressing these challenges is crucial for optimizing ESP performance and ensuring economic viability.

Under this context, Abu Dhabi Offshore Fields, as part of its field development plan, has adopted ESP as its artificial lift system. In consideration of this ambitious project, Abu Dhabi Offshore Fields is proactively engaged in laying the groundwork to manage these wells with the highest operational efficiency. This involves strategic planning for the installation, maintenance, and monitoring of the ESP systems to ensure they deliver optimal performance and longevity. Therefore, continuous surveillance of the system is a must, especially considering that common ESP failures are categorized as follows: Electrical Failures, which are the most prevalent, making up about 60% of all ESP failures, including power failures, under-voltage, voltage imbalances, and motor underload. Motor Failures can result from overheating, insulation breakdown, or mechanical wear and tear. Gas Locking occurs when gas accumulates in the pump, hindering its operation. Mechanical Failures include issues like impeller wear, shaft breakage, and seal failures. Operational Failures arise from improper installation, poor maintenance, and operational errors.

Recent advancements in Artificial Intelligence (AI) offer promising solutions to mitigate these operational challenges. AI technologies, including machine learning and predictive analytics, can provide significant improvements in the management and optimization of ESP systems. For instance, predictive maintenance algorithms can analyze historical and real-time data to forecast equipment failures, allowing for proactive interventions that reduce downtime and extend the lifespan of ESP components. Similarly, AI models can predict sand production trends and recommend optimal operational parameters, minimizing sand ingress and associated issues.
Novel Approach of Reservoir Management to Ensure Reservoir Healthiness and Gas Availability to the Network
Authors: Al Yaqoubi Nouf , Sudarev Maxim , Latypov Eduard , Al Bairaq Ahmed , Alawadhi Fatima , Nachiappan Ramanathan , Al Hammadi Shamma , Al Shamsi Alia , Fathalla Magdy Farouk
Published: November 2024

The study accentuates the need for enhancing productivity and sustainability by curtailing the new wells drilling requirement and building associated infrastructure. The system implements a recycling process in the reservoir to enhance condensate collection and maintain pressure by dividing the reservoir into sectors. This method is especially beneficial in situations where there is a lack of make-up gas or the need to generate gas that is suitable for the market. This approach involves careful allocation of injection gas to maintain pressure and prevent early gas breakthrough. The goal is to divide the reservoir based on geological information and improve operation tactics for each well, including reallocating injections and detailed development plans. The first use of data such as rock layers along with tracking and production/injection figures helps verify the division strategy. This has led to improved condensate yield without extra costs. A plan has been created, specifying allowed injection rates for each injector, resulting in better condensate extraction and a prolonged gas output level.

By converting underperforming vertical wells into horizontal ones, we've increased the contact with the reservoir and enhanced output. Focusing on condensate-rich areas through strategic drilling at the periphery is a key part of our approach. Sectorization, along with horizontal and peripheral drilling, has significantly boosted ultimate recovery and production efficiency, with sectorization adding about 0.5% to recovery rates, horizontal drilling contributing an extra 1.5%, and peripheral efforts increasing it by about 4%, leading to an overall improvement in condensate recovery by roughly 5-6%.

The main goal is to secure a sustainable and profitable supply of gas, both presently and looking ahead, by enhancing the recovery process from a vast Gas-Condensate Reservoir in the UAE. The approach includes setting objectives, ordering priorities, and designating resources for actions and assessment methods to reach these objectives. This study presents a novel method to improve the exploitation of a substantial gas-condensate reservoir, with a focus on optimizing condensate retrieval while preserving reservoir pressure, and prioritizing decarbonization and emission reduction.
Hydrogen Storage Opportunities in UAE: Potential Innovations and Advances
Authors: Lyakhovskaya V. R. , Magomadov I. A. , Balhasan S. A. , Lamboi J. , Mahmoud S. Nagy Fathy Mohamed
Published: November 2024

The paper aims to explore hydrogen storage opportunities in the UAE, focusing on the potential of salt domes in the region. It evaluates the technical, environmental, and sensitivity aspects of utilizing salt domes for large-scale hydrogen storage, aligning with the UAE's strategic goals for energy transition and decarbonization. This study employs a comprehensive approach that includes geological analysis, cavern design, and sensitivity assessment.

The methodology involves identifying and characterizing suitable salt domes, designing storage caverns, and calculating their capacity. It also incorporates sensitivity analysis using Monte Carlo simulations to evaluate uncertainties and risks, alongside suggests advanced monitoring systems to ensure structural integrity and safety of proposed salt caverns.

The analysis identifies several salt domes, such as Jebel Dhanna, Delma, and Sir Bu N'Air, as highly suitable for hydrogen storage. The designed caverns show significant storage capacity, with a median of 1144 caverns capable of storing approximately 503 million pounds of hydrogen. Sensitivity analysis highlights dome diameter and edge length as critical factors influencing storage capacity. Advanced monitoring systems and safety measures are proposed to mitigate risks associated with structural integrity and gas leakage. The findings support the UAE's strategic commitment to advancing hydrogen storage, contributing to energy security and the transition to a low-carbon future.

This paper presents novel insights into the feasibility of using UAE salt domes for hydrogen storage, combining detailed geological analysis with advanced design and risk assessment techniques. It offers practical guidance for implementing large-scale hydrogen storage projects, contributing to the existing body of knowledge and supporting the UAE's leadership in the hydrogen economy.
Optimizing Data Driven Recruitment Strategies in a Disruptive Era Through Digital Workload Analysis
Authors: Handayani S. , Kusumaningtyas R. , Wicaksono D. , Putri N. Sasmita , Triasnita C.
Published: November 2024

To emerge as a leading global energy company, an agile structure that facilitates business acceleration and operational excellence is necessary. However, following a recent subholding restructuring, the organization faces a 23% vacancy rate. This situation is compounded by the dynamic business landscape, which makes additional challenges to recruiting efforts. To address these issues and ensure an effective recruitment strategy to maintain productivity while adapting to the changes, a comprehensive organizational evaluation and processes is essential. A digitalized Workload Analysis (WLA) application was implemented to comprehensively assess staffing needs of 6,200 positions across the organization, including structural and contracted positions. This approach addressed limitations of conventional WLA methods such as data validity and extended timeline. Pre-filled questionnaires based on standardized job descriptions ensured data accuracy, and sharing sessions for high-level management, Subject Matter Experts (SMEs), and all respondents, further enhanced completion quality. Additionally, technical guidance and support were offered in various forms, including online/offline assistance, instructional videos, and interactive communication channels. This streamlined WLA process was completed within two months. The analysis resulted in some critical insights: among the 23% vacancy rate, 15% were identified as high-priority roles within core operational teams. Another 3% could be eliminated, while recruitment for another 5% could be deferred based on anticipated business developments. These findings informed targeted recruitment strategies, timelines, and resource allocation, ensuring efficient workforce management. Emphasizing a data-driven approach, it optimizes the recruitment process and identifies opportunities to enhance efficiency by eliminating redundant positions, supporting the company to swiftly adapt to evolving talent demands and ensuring readiness in the dynamic business landscape.
Fast Track Development of Omani Fresh Graduate Geologists
Authors: Al Hadhrami Fahad , Al Rashdi Hilal
Published: November 2024

The rapid development of the discovered hydrocarbon reservoirs and utilization of discovered resources in Oxy Oman have necessitated the swift growth and professional advancement of local geologists. This abstract highlights the significance and potential strategies for fast-tracking the development of Omani fresh graduate geologists to meet the company's increasing demands for skilled professionals in the field of exploration and development geology.

With the surge in exploration and development activities, there is a growing need for a well-trained workforce equipped with advanced geological knowledge and practical skills. To address this demand, a comprehensive approach to expedite the development of Omani fresh graduate geologists is crucial.

Established for the first three years of career development with clear milestones. This program covers essential technical skills through on job training, well site experience in the drilling rig for six months, and exposure to various operation geology challenges of different reservoirs. This is alongside the incorporation of classroom training, computer-based training, hands-on practical exercises, and field visits to enhance their understanding and skills.

Secondly, a mentorship program was established, where experienced geologists within Oxy Oman can guide and support fresh graduates. Each graduate is assigned a mentor who can provide guidance, share knowledge, and help them navigate their career development within the company.

Furthermore, rotational assignments are offered to fresh graduates to work in different departments such as exploration and development fields from Oman North and Oman South between three to six months within the company. This provided them with a broader perspective of the company's operations and exposed them to different geological challenges and solutions.

A regular performance evaluation system was established to assess the progress of the fresh graduates reported monthly to quarterly by the mentors. Constructive feedback was provided to identify areas of improvement to help them grow professionally. As part of the assessment, the fresh graduates were asked to present their progress development and their study work or experience.

Regular knowledge-sharing sessions were also arranged where experienced geologists can share their expertise, insights, and lessons learned with fresh graduates. This was done through presentations, workshops, or informal discussions.

In conclusion, the fast-track development of fresh graduate geologists is crucial to meet the increasing demands of the company's rapidly expanding reservoir discoveries. By focusing on robust training programs, continuous professional development, continues mentoring with constructive feedback, and management support, Oxy Oman is effectively producing a skilled and proficient geology workforce that contributes to field discoveries and development growth.
Influence of the Bacterial Factor on the Change in Formation Permeability During Produced Water Reinjection
Authors: Kurbasov Maksim , Saikia Tinku , Øye Gisle , Feilberg Karen L.
Published: November 2024

On Danish fields in the North Sea, a large amount of produced water is generated. The problem of disposing of this volume is a major challenge for the oil and gas sector in general. Produced water is a complex mixture of dispersed and dissolved components. The former includes dispersed oil and solids, while the latter can consist of water-soluble organic compounds, dissolved salts, and production chemicals (Dudášová et al., 2014). According to a report by the Danish Energy Agency (2023), 30.8 million cubic meters of produced water are extracted annually. One method of disposing of this volume is discharging produced water into the North Sea. However, this approach is a primary source of ocean pollution with crude oil and PAHs, affecting the populations of biota in the water column (Beyer et al., 2020). Additionally, produced water contains heavy metals and radioactive materials (Hansen and Davies, 1994), which can impact food security in the discharge region (Milenkovic et al., 2019).

As an alternative, the process of reinjecting produced water is used to maintain reservoir pressure and displace hydrocarbons from production wells (Saripalli et al., 2000). Produced water undergoes a purification process that includes degassing, oil separation, biological treatment, coarse purification, and deoxygenation, after which it is injected into the reservoir (Fakhru'l-Razi et al., 2009). However, this method is associated with several disadvantages. As operator practices show, the decline in permeability during the reinjection of produced water leads to a rapid decrease in reservoir permeability, necessitating additional measures to control oil and gas inflow. The decline in permeability during the reinjection of produced water poses a significant obstacle for oil and gas companies in the North Sea region.

The presence of total suspended solids (TSS) (Ye et al., 2013), total dissolved solids (TDS) (Hosseinzadehsadati et al., 2024), oil content (Zyleyka, 1999), and bacterial growth (Gandler et. all, 2006) can accelerate the decline in injectivity in injection wells. In the context of reinjecting produced water into chalk reservoirs, the fluid composition, temperature, and presence of organic contaminants play a more significant role due to the very low permeability (typically less than 2 mD) and high porosity (more than 20%) of chalk formations (Childs and Reed, 1975).
Examining Gas Expansion at the Pore-Scale for Underground Hydrogen Storage
Authors: Dokhon Waleed , Goodarzi Sepideh , Alzahrani Hussain M. , Blunt Martin J. , Bijeljic Branko
Published: November 2024

The impact of hydrogen expansion during pressure decline on remobilizing trapped gases was examined within Bentheimer sandstone. The invasion mechanisms in gas expansion and injection were differentiated. Previous studies focused on gas trapping through displacement by water, whereas pressure decline is the primary mechanism for extraction in field operations. A dimensionless ratio was derived to compare advective displacement and expansion to determine the dominant mechanism during gas withdrawal and pressure decline.

High-resolution micro-CT images at a 3 μm/voxel were used to analyze dynamic changes in gas distribution and remobilization. A water-wet porous plate was used prevent hydrogen production during displacement. A pressure decline rate of 100 kPa/day from 1 MPa to 0.35 MPa was applied during gas expansion, while a constant differential pressure of 11 kPa was imposed during gas injection. Images were acquired every 24 hours to study dynamic changes in gas distribution and fluid occupancy in pores.

Distinct hydrogen behaviors were observed during expansion compared to injection. It was demonstrated that in gas injection, hydrogen advances from a connected cluster in an invasion-percolation type process, whereas in gas expansion, hydrogen accesses more pore space, including from disconnected clusters. The average gas saturation in the sample increased from 0.3 to 0.5 by gas expansion, with an estimated 10% of the expanded volume attributed to hydrogen exsolution from the brine. The spatial distribution of hydrogen during expansion showed a broader lateral spread, while in gas injection, the path was more preferential to one side.

Valuable insights into hydrogen behavior under dynamic pressure conditions in remobilizing trapped gases were introduced, potentially linking to higher withdrawal efficiency. This research can be extended to simultaneously include imbibition and pressure decline to assess the relationship between gas withdrawal and gas expansion.
OCTG Connections Test Protocol for Underground Hydrogen Storage
Authors: Martin Pierre , Roordink Patrick , Bernard Justine , Bouffler Laurent , Dugaz Sébastien , Evin Harold
Published: November 2024

Hydrogen storage is a key technology to deploy a sustainable hydrogen supply from producers to users. It can be massively stored underground in salt cavern through wells. Storage safety needs to be carefully managed especially by ensuring the gas sealability of hydrogen wells. Vallourec Research and Development department has investigated and evaluated a new qualification protocol for hydrogen storage to validate proprietary large integral premium connection for underground hydrogen storage.

A 9-5/8″ 47.00# L80 proprietary threaded and coupled connection has been used by EnergyStock in a 1290m depth underground hydrogen test borehole in the Netherlands from February 2022 to January 2023. Several pressure cycles were made at 100% hydrogen in this storage. The storage pressure was 200 bar. Based on these real operating conditions, in 2024 a new hydrogen test protocol has been applied on 16″ 109# 110ksi premium integral connection. Indeed, some hydrogen well architectures feature tubing diameters up to 16″ with potentially higher pressure, higher temperature and high number of shallow cycles.

The 9-5/8″ 47# L80 connection and the pipe were retrieved and inspected by Gasunie and Vallourec teams to check if any cracks or corrosion were visible. In order to cover a wider range of hydrogen storage applications, the protocol defined by Vallourec in 2021 has been improved and made more demanding. All tests are conducted with 5% H2/95% N2. A first sequence of 10,000 pressure cycles is performed at 475 bar with variations of +/- 25 bar to simulate daily loading and withdrawal operations. A second sequence to represent seasonal operations is conducted with pressure variations ranging from 30 to 500 bar and temperatures up to 180°C to cover a wide range of heating that may be encountered with the inverse Joule-Thomson effect. A third test sequence is conducted following Series B of API RP 5C5. Finally, a sequence of internal pressure testing is performed at 95% of the maximum pipe pressure. In addition, a 100% H2 pressure test is conducted on the connection to demonstrate its performance in pure hydrogen. A proposal is also made to submit the premium connection to external pressure with 5% H2/95% N2 to evaluate the impact of debrining operations on the connection.

No current standard is available to assess OCTG connection for underground storage applications. The test protocol developed demonstrated that the connection evaluation is necessary for such application. The evaluated connection successfully passed the hydrogen test protocol. A return of experience on the connection performance in a salt caver after exposure to 100% H2 high pressure is also provided.
Successful Water Shut-Off Utilizing Lower Completion ICD+SSD – Actual Case Study of Marginal Oil Field of Onshore UAE
Authors: Dani C.
Published: November 2024

Marginal oil fields often experience critical and challenging periods to sustain oil rates above minimum economic thresholds. Mitigative measures such as installation of lower completions (LC) help to control water production (water shut-off) and sustain oil production. In SPE-211320-MS, clear definition of data driven based candidate screening process for LC was discussed in detail. This paper will elaborate actual examples on LC design, post LC installation evaluation and describe several key factors to be considered when designing the LC implementation. In addition, well performance-based metrics will be highlighted to showcase the success of water shut-off (WSO) utilizing the LC implementation.

It is critical to collect key data prior to preparing the LC design, which will ultimately impact the success of the LC implementation. Fresh production logging data and available open hole logs should be appropriately mapped and placed on the same page to analyze any information supporting the LC design. A collaborative review amongst petroleum engineers, Petro-physicists and other disciplines is necessary to understand and agree on the final data to be used for the design. Subsequently, the LC simulation designs should attempt to match the current well conditions and production. The simulations should involve testing sensitivities with different ICD+SSD settings and locations to obtain the best and most suitable results. A favorable outcome from this work should be to reduce water cut as much as possible from the original performance.

Post LC installation, well production performance will be reviewed to assess the effectiveness of the LC configuration to achieve the targeted water cut. If necessary, production logging will be run to confirm that all LC elements are functioning as per the design.

Before implementing the LC, four (4) wells were tested for installing ESP (Electric Submersible Pump) without LC. The results were unexpectedly negative, with WC increasing to 60-80% within two months. This trial will serve as a baseline for reviewing the success of LC implementation.

Up to date, LC has been deployed in 28 wells and the results were evaluated based on WC reduction, improved accessibility, and LC equipment functionality. The post-LC installation results were impressive and key findings were gathered to improve the LC design. Three (3) wells with successful water shut-off will be presented in this paper.

There have been many lessons learned and derived best practices of LC implementation from this study. This success of water shut-off could copied to other Field in similar reservoir condition. Moreover, guidelines, best practices and documentation have been developed for both internal future marginal field developments and could be leveraged for other oilfield operators to plan successful water shut-off attempt.
Executing Marginal Field Project with a DBO Design, Build, and Operate Strategy Onshore Abu Dhabi
Authors: Saadawi H. , Al Rumaithi F. , Abdelhadi S. M. , Al Jabri T. A.
Published: November 2024

Al Dhafra Petroleum Company recently commissioned a Custody Metering Project using a DBO (Design, Build and Operate) strategy. Project facilities, which were designed to handle 50,000 BOPD, include single stage 3-phase separator, oil booster pumps, a custody meter package to measure the partially stabilized crude oil. The project facilities also include associated piping and utilities.

This paper describes the experience of executing the project using a DBO concept. The tendering requirements and company role during the execution of the DBO contact are described. The paper also discusses the merits of DBO Contracting strategy in comparison to the traditional FEED / EPC approach for project execution. Lessons learnt, recommendations, contractual, technical and assurance challenges associated with DBO strategy are presented.
Hydrogen Blending In Western Australia Gas Network - Pilbara Pipeline System
Authors: Farah Tania , Emad Maryana , Haq Bashirul , Al Shehri Dhafer , Mahmoud Mohamed
Published: November 2024

Hydrogen blending with natural gas (H2-NG blending) is a pragmatic solution to effectively mitigate and tackle the carbon footprint of natural gas consumption while providing an economical means of transporting large-scale H2. The study aims to evaluate the Pilbara Pipeline System for H2 transportation. It offers the effect of varying H2 concentrations within the gas mixture on the corrosion rates, erosional velocity ratio (EVR), and pressure performance at each 50 km interval along the pipeline.

The APA Group's Pilbara Pipeline System spans 216 kilometers, transporting gas from the Burrup Extension Pipeline to Port Hedland with a capacity of 166 TJ/d. Using an innovative approach, we developed a simulation model in PIPESIM-Net software that integrates a GIS map to capture precise terrain profiles, calculate pressure drops, and accurately replicate steady-state gaseous flow. It incorporates parameters like pipeline specifications, and elevation, and specifies nodes (sink/source) with appropriate boundary conditions (pressure or flow rate), including the gas composition. Model accuracy was verified against historical data, and a sensitivity analysis assessed network performance by varying H2 concentration.

The findings show that as the H2 concentration increases, the corrosion rate rises a little, with 80% H2 showing the highest corrosion rate, followed by a decrease in the H2 fraction every 10% and the reported corrosion rates (CRs) remain within the safe limits recommended by the National Association of Corrosion Engineers (NACE), which are less than 0.4 mm/a. This increased pressure along the pipeline due to higher levels of H2. However, the erosional velocity ratio exhibits a contrasting trend, increasing H2 composition resulted in a slight decrease in EVR. In all scenarios, the observed EVR values at checkpoints along the pipeline route remained below the safe limit of 1, indicating no erosion risk. The corrosion rates and EVR are both noteworthy for being within the industry-acceptable range, confirming the system's overall safety and practicality for blending H2-NG.

This pioneering study comprehensively evaluates the impact of corrosion rate, EVR, and pressure profile on H2-NG blending in the Pilbara Pipeline System. Utilizing an innovative simulation model incorporating precise terrain profiles and elevation data, we provide novel insights into corrosion rates and EVR variations with H2 concentration. Our findings demonstrate the system's safety, and practicality, and address a significant research gap, illuminating corrosion, erosion, and pressure dynamics specific to this pipeline network.
A-to-I RNA editing of CYP18A1 mediates transgenerational wing dimorphism in aphids
Authors: Zhu Bin , Wei Rui , Hua Wenjuan , Li Lu , Zhang Wenlin , Liang Pei
Published: November 2024

Wing dimorphism is a common phenomenon that plays key roles in the environmental adaptation of aphid; however, the signal transduction in response to environmental cues and the regulation mechanism related to this event remain unknown. Adenosine (A) to inosine (I) RNA editing is a posttranscriptional modification that extends transcriptome variety without altering the genome, playing essential roles in numerous biological and physiological processes. Here, we present a chromosome-level genome assembly of the rose-grain aphid Metopolophium dirhodum by using PacBio long HiFi reads and Hi-C technology. The final genome assembly for M. dirhodum is 447.8 Mb, with 98.50% of the assembled sequences anchored to nine chromosomes. The contig and scaffold N50 values are 7.82 and 37.54 Mb, respectively. A total of 18,003 protein-coding genes were predicted, of which 92.05% were functionally annotated. In addition, 11678 A-to-I RNA-editing sites were systematically identified based on this assembled M. dirhodum genome, and two synonymous A-to-I RNA editing sites on CYP18A1 were closely associated with transgenerational wing dimorphism induced by crowding. One of these A-to-I RNA editing sites may prevent the binding of miR-3036-5p to CYP18A1, thus elevating CYP18A1 expression, decreasing 20E titer, and finally regulating the wing dimorphism of offspring. Meanwhile, crowding can also inhibit miR-3036-5p expression and further increase CYP18A1 abundance, resulting in winged offspring. These findings support that A-to-I RNA editing is a dynamic mechanism in the regulation of transgenerational wing dimorphism in aphids and would advance our understanding of the roles of RNA editing in environmental adaptability and phenotypic plasticity.
Environmental cues influence timing and location of construction activity in a beaver damming complex
Authors: Kennedy Jordan , McCreery Helen , Jones Audrey , Chen Candice , Fairfax Emily , Werfel Justin
Published: November 2024

Beavers are famous for building extensive damming complexes 1 , which can extend over kilometer-scale distances2 and persist for centuries3. Dams have major impacts on their surrounding environment, including effects on the hydrology, geomorphology, and ecosystems of the area4. Current understanding of how the environment in turn affects beavers’ building activity centers on the single auditory cue of running water, based primarily on captive studies14,15. Observational challenges have limited a more detailed picture of the full feedback loop between beavers and their environment. Here we describe the detailed progress of new construction by 20 beaver colonies in northwest Montana, through field studies using drones to obtain surveys with spatial and temporal resolution each three orders of magnitude finer than typically reported5–13. We show that both the timing and location of beaver construction activity are influenced by environmental factors. Initiation of trail clearing, a stage preceding dam building, was associated with a narrow range of stream flow rates. Beavers preferentially built in locations associated with preexisting canals. These results emphasize the importance of non-dam elements in the beavers' construction and its coordination across the colony, and point to environmental feedback processes that may span across years and unrelated colonies.
Placenta location, a prognostic determinant for the incidence of preeclampsia
Authors: Alikhani Fariba , Aalinezhad Marzieh , Bahrami Mahshid , Geravandi Mahsa
Published: November 2024

Background: Preeclampsia is one of the complications of pregnancy with uncertain etiology. Nevertheless, it is believed that the condition may arise due to abnormal trophoblastic invasion, resulting in vascular remodeling and increased resistance in the spiral arteries. It is assumed that the location of the placenta might have contributed to the formation of trophoblastic invasion and further placental supply. The current study aims to investigate the association of placental location with the incidence of preeclampsia
Methods: The current case-control study was conducted on 206 primigravid pregnant patients undergone routine screening ultrasonography study between 14 and 26 gestational weeks to determine the location of the placenta (anterior, posterior, or lateral). The patients were categorized as cases that met the criteria of high-risk for preeclampsia (n=106) or the controls (n=100).
Results: Logistic regression assessment revealed that increased age (OR: 1.047, 95%CI: 0.89-1.12; P-value=0.033), BMI> 25 kg/m2 (OR: 4.61, 95%CI: 1.02- 10.02; P-value=0.038), and anterior (OR: 2.79, 95%CI: 1.08-9.43; P-value=0.038) and posterior (OR: 1.056, 95%CI: 0.89-1.12; P-value=0.033) location of placenta were the predicting factors for the incidence of preeclampsia.
Conclusion: Based on the findings of the current study, anterior and posterior location of the placenta, increased age and BMI above 25 kg/m2 were the predicting factors for preeclampsia development. Given that, it is recommended to closely monitor the individuals with anteriorly located placenta aiming at early diagnosis of persistent hypertension and applying approaches to minimize the adverse effects of preeclampsia.
Effect of surface grafting on the oil-water mixture passing through a nanoslit: A Molecular Dynamics Simulation Study
Authors: Tian Wende , Wang Yanwei , Toktarbay Zhexenbek
Published: November 2024

Graphene oxide-based membranes hold great promise in composite materials for applications such as wastewater treatment and oil-water separation. In this study, we employed molecular dynamics simulations to investigate the separation of water from an oil-water mixture using a two-layer graphene oxide membrane. We explored the effects of random and stripe-like grafting patterns on penetration efficiency, focusing on varying grafting densities. Our results show that increasing grafting density reduces flux and permeability of both oil and water molecules, highlighting the critical role of surface functionalization in membrane design. Notably, the stripe grafting pattern significantly enhances penetration efficiency by optimizing steric interactions around the nanoslit. These findings contribute to the development of nanocomposite materials and surface modification techniques, offering insights into the design of high-performance membranes for oil-water separation. Understanding the relationship between grafting density, surface patterning, and membrane performance is crucial for advancing hybrid materials that address industrial challenges such as wastewater treatment and oil spill remediation. The insights gained from this study can be further refined by exploring different functional groups and surface modifications, broadening the applications of these membranes in industrial separation processes.
Identification of common core genes and pathways of sepsis and cancer by bioinformatics analysis
Authors: He Yi-Ran , Ding Ni , Han Ming-Chen , He Hong-Yu , Xuan Li-Zhen , Gu Zhun-Yong , Zhong Ming , Ju Min-Jie
Published: November 2024

Introduction
Both sepsis and cancer are leading causes of death worldwide, and they share a number of pathophysiological features. Some studies have suggested a possible association between sepsis and cancer, but few have studied core genes in both diseases.
Methods
Common core genes were identified from sepsis datasets (GEO: GSE26378, GSE4607, GSE8121 and GSE13904) and cancer databases (TCGA: BRCA, COADREAD, ESCA, KIRC, LIHC, LUAD, STAD). Then, GO and Reactome enrichment analyses and PPI network analysis were performed. Pharmacophore screening was used to predict the targetsof oxymatrine and ulinastatin,and potential target genes in both cancer and sepsis were obtained. Survival analysis was performed. The association between the target genes and tumor size and number of positive lymph nodes was investigated by Pearson correlation analysis. The association between the target genes and tumor stage was investigated by Fisher’s exact test. Molecular docking analysis was performed to evaluate the affinity of the candidate drugs for their targets.
Results
In total, 641 common genes were identified. GO enrichment analysis showed that common genes were enriched in neutrophil degranulation, inflammatory response and innate immune response. Reactome enrichment analysis showed that common genes were enriched in neutrophil degranulation, interleukin-4 and interleukin-13 signaling, transcriptional regulation of granulopoiesis and interleukin-10 signaling. The PPI network showed that the top 10 core genes were TLR4, IL1B, IL10, ITGAM, TLR2, PTPRC, CDK1, FOS, MMP9 and ITGB2. The survival analysis showed that the high expression of BCAT1, CSAD, G6PD, GM2A, MMP9, PYGL and TOP2A was associated with poorer prognosis in several cancers. Molecular docking showed that oxymatrine and ulinastatin can bind to protein targets with highly stable binding.
Conclusions
We identified genes with common effects on both sepsis and cancer, which provides new insights into the association between sepsis and cancer. In addition, two drugs with potential clinical application value were identified. Further studies are required to validate the role of these common core genes in sepsis and cancer and to evaluate the potential utility of these drugs.