bluuebunny/crossref_metadata_2025 huggingface dataset:
Bayesian-Based Approach in Soil Characterization for Top-Hole Design
Authors: Varady C. , Tenório J. , Silva E. , Junior E. Lima , Santos J. , Dias R. , Cutrim F.
Published: April 2024

This paper addresses Bayesian-based data-driven site characterization methods for estimating soil parameters used in top-hole casing design. Different models are applied to datasets of piezocone tests (CPTu) conducted in Brazilian fields and their performance is compared to some characterization techniques currently employed by the oil and gas industry. Regression models are crucial for soil characterization for top-hole casing design. Data-driven methods consist of a powerful tool for this purpose, allowing handling uncertainties originating from soil variability. This paper addresses machine learning models devoted to sparse data, namely Geotechnical lasso (Glasso) and Gaussian Process Regression (GPR) from a Bayesian perspective considering prior knowledge of site information. This approach provides statistical information on soil parameters like undrained shear strength, supporting structural analysis of wellhead systems, and conductor/surface casing strings. Datasets were collected from in-situ CPTu tests conducted in the Campos basins, in eastern Brazil. The first case study addressed primary CPTu data, including cone tip resistance, friction sleeve, and total pore pressure, to characterize undrained shear resistance as a random variable. In this context, the parameter was modeled using Phoon´s modified Bartlett test to calculate sample sizes that ensure stationarity. This approach presented relevant results in assessing the probability of failure for conductor and surface casing design based on the operator´s internal design criteria. As these applications, more robust techniques were used to improve data characterization. Glasso and GPR models are used to model parameter tendencies and evaluation of the random data. These methods differ in prior probability density functions adopted - Laplace and Gaussian, respectively - and they are compared with regression techniques widely used in design practice. All the models were trained to estimate undrained shear resistance. Preliminary results confirm that the technique improves the characterization of soil strata and undrained shear strength, with a beneficial effect on the analysis of offshore top-hole structural design cases. Some metrics such as Mean Absolute Error (MAE) and Root Mean Squared Error (RMSE) indicate that GPR outperforms other methods. This is an innovative methodology applied in real-case scenarios with data ceded from the partner operator. The formulation evaluates uncertainties associated with the spatial heterogeneity of the material, continuously improving robustness with each new project data. This enables a better understanding of soil behavior in specific oilfields and can assist the decision-making process in well design, improving operational safety. Furthermore, the results of the statistical modeling support reliability-based analysis to deliver probability-based indicators for well integrity design.
Automating Prediction of the Formation Tops and Lithology Changes in Real-Time While Drilling Using Artificial Neural Networks
Authors: Mahmoud Ahmed Abdulhamid , Elkatatny Salaheldin , Abdulraheem Abdulazeez
Published: April 2024

Determining formation tops in hydrocarbon wells is a critical aspect of drilling operations, impacting decisions related to casing setting depths and drilling fluid design. Traditionally, estimates are made based on geological data during the exploration phase, but these lack precision. Real-time updates to formation tops occur as new wells are drilled, incorporating data from various measurements like Rate of Penetration (ROP), gamma ray, formation cuttings, and mud logging. However, these measurements come with limitations such as high costs, manpower requirements, and time or depth lags.

This study introduces an innovative alternative using Artificial Neural Networks (ANNs) to accurately predict formation tops. The ANNs model incorporates drilling mechanical parameters and ROP to address limitations in existing techniques, aiming to predict genuine ROP changes irrespective of other drilling parameter fluctuations. Real-field data from two Middle Eastern vertical oil wells was utilized to validate this approach. The study explored different smoothing techniques and identified the moving average technique with a span of 5 as effective in smoothing data while preserving structure.

The ANNs model was trained with 70% of Well-A’s data and tested on the remaining 30%, with validation using Well-B data. The sensitivity analysis revealed that an ANNs model with 25 neurons and one hidden layer, using the trainlm training function, achieved optimal results. For testing data from Well-A and the validation date of Well-B, correlation coefficients (R) were 0.94 and 0.98, respectively. This innovative approach offers a cost-effective solution, overcoming challenges associated with traditional methods. It provides accurate, real-time predictions for formation tops during well drilling, ensuring better decision-making in casing programs and drilling fluid design, ultimately contributing to more efficient and cost-effective well operations.
Wet Christmas Tree – New Approach to Model Next Generation Control and Monitoring Systems
Authors: Pozzani D. , Kotsugai A. , Rabello A. , Silva A. H. , Coelho E. , Borda F. G. , de Souza M. A. , Carvalho L. O. , Beppler R. V.
Published: April 2024

This initial proposition presents a conceptual design regarding the upcoming aspects of a standardized wet Christmas tree (WCT) with electrification aspects. The study comprises not only fail safe close electrical actuators and its control system but also integration aspects, leading to an analysis of the complete system. The objective is to conceptualize a standardized electrical WCT system with quality and suitability equivalent to those of the standard electrical/hydraulic multiplexed control (EHMUX) WCT system applied in Brazilian Pre-Salt fields.

The use of a standardized Pre-Salt WCT, is the key to have time and cost reduction on a new WCT system, based on a 10 years’ experience in operating on Pre-Salt Basin conditions. The EHMUX system has proved the efficiency and is a robust system able to operate in 2500m depth and 10000psi, with high carbonic gas concentration. Therefore, the main idea is to use this platform to a conversion to a high reliability electrical WCT system with Fail Safe Close, using a new electrical actuator qualification program. One of the most important features of a new electrification system must having is a capacity to transduce production or injection conditions into readable variables where this set of information will be useful either to monitor, control and estimate other information such as life cycle considerations (e.g., maintenance), components or subsystems deterioration, and equipment’s life extension.
A System of Connected Digital Twins with Artificial Intelligent Solutions - The Key to Resolving the Energy Trilemma
Authors: Hansen O. H. , Jaiswal V. , Eriksson K.
Published: April 2024

For many years, the energy industry has faced the energy trilemma, implying a need to prioritize between: secure, clean, and affordable energy. Balancing the energy trilemma has always been a challenge, but the geopolitical situation since the war in Ukraine has forced the world to prioritize energy security. As a result, clean and affordable energy have taken the backseat. Solving the trilemma could make the world’s energy systems more volatile, unpredictable, and complex. The need today is to accelerate the digital transformation of the energy systems and establish a system of connected digital twins with trustworthy Artificial Intelligence (AI) solutions to go towards net zero in an affordable way.
Anchor Project: Best Practices and Lessons from Detailed Design Through Fabrication of the Anchor FPU
Authors: Falcon R. , Braun C. , Klaus K. , Shinde S. , Wu G. , Rodriguez I.
Published: April 2024

The Anchor semi-submersible floating production unit (FPU) is a Chevron operated Gulf of Mexico (GOM) deepwater facility with a nameplate capacity of 75,000 bopd and 28 mmscfd and future expansion capability. This paper provides an overview of the FPU from detailed design through fabrication including design philosophy, equipment selection, pre-investment, and construction methodology as well as insights into Anchor’s contracting and execution strategy. Principles such as minimum functional objective (MFO), conditions precedent (CP), and on-ground max are discussed, as are some of the key decisions that enabled successful delivery of the Anchor FPU such as early contractor engagement and implementation of a rigorous weight management program. Final investment decision (FID) for the Anchor project was reached in 4Q2019 and soon after in early 2020, the world began to experience impacts from the COVID-19 global pandemic. Actions taken by the Anchor project team to address the many challenges of executing a major capital project (MCP) during a global pandemic and market downturn will also be shared.

Anchor followed a general contracting strategy similar to past projects executed by Chevron in the GOM. While this approach requires a larger Owner’s team to manage multiple contracts and interfaces, it also provides greater visibility and earlier recognition of potential execution challenges thereby enabling the project team to react faster with direct input to mitigate or address issues as soon as they are identified. A large number of contracts were executed to deliver the FPU including separate topsides engineering, hull engineering, topsides fabrication and integration, hull fabrication, and systems completion contracts. The Anchor hull was fabricated in South Korea and transported via a heavy transport vessel to the Anchor topsides fabrication site in the US Gulf Coast where the topsides was integrated to the hull. Construction was completed in May 2023 and the Anchor FPU was wet towed from the fabrication yard to its final location in the GOM for installation and execution of the offshore hookup & commissioning (HUC) campaign.

For clarity, the following terms are used throughout this paper. High Pressure High Temperature (HPHT) refers to equipment rated to pressures greater than 15,000 psi and/or temperatures equal to or greater than 350°F. Anchor is a high pressure project under the HPHT category. 20K refers to the Anchor project’s technology development and qualification program.
Probabilistic Lateral Buckle Formation for Three Deepwater HPHT Pipeline Mitigations
Authors: Valer C. I. , Bai Q. , Cardoso P. , Jebali A. , Almeida R. , Mendes A.
Published: April 2024

A comparison assessment of lateral buckle (LB) formation among three typical buckle mitigation devices (sleeper, distributed buoyancy modules (DBM), and residual curvature method (RCM)) commonly considered in the design of high pressure and high temperature (HPHT) flowlines is carried out by adopting a probabilistic approach based on Virtual Anchor Spacing Finite-Element (VAS FE) modeling to assess buckle initiation reliability. The pros and cons of each device are detailed, the critical stochastic parameters and deterministic parameters for the buckle formation associated with each device are identified, and a probabilistic assessment via a case study is carried out using the three mitigation devices for a subsea deep-water HPHT production flowline.

The probabilistic assessment of pipeline lateral buckling includes the following: (1) Calculation of the critical buckling force (CBF) and its probability density function for both engineered and rogue buckles based on deterministic and stochastic parameters via Monte-Carlo simulation and design of experiments (DOE); (2) Determination of the tolerable VAS by FE analyses for both engineered and rogue buckles to satisfy the design criteria; (3) Positioning of the engineered buckles along the flowline through a reliability analysis using BUCKFAST.

The analysis results indicate that the stochastic parameters that control the buckling formation are different for each of the three mitigation methods. Comparison of the three methods showed that the RCM option had the most significant impact on reducing the CBF due to the influence of the pipe/soil lateral breakout friction factor while the DBM option had the least significant impact, with the highest CBF among the studied mitigation devices. Results also show that some of the stochastic parameters do not have significant effects on the CBF for each considered mitigation device and therefore could be treated as deterministic parameters in future analyses. The competition between the CBF of rogue buckles along the curve section and the trigger CBF distribution is the key parameter when comparing the different mitigation methods. Sleeper and DBM options may not satisfy the LB design criteria in some cases when using the deterministic approach, especially for a rough seabed profile along the route, but may lead to a solution when using a probabilistic assessment. RCM has the advantages of a lower CBF and the lowest cost among the three mitigation methods, which means the RCM is a cost-effective lateral buckle mitigation solution for subsea HPHT pipelines.
A Trustworthy Digital Twin for Data Driven Verification
Authors: Hansen O. H. , Stang J. , Jaiswal V.
Published: April 2024

Traditionally, verification of equipment and systems has been carried out by deploying surveyors to perform physical verifications. Today, the development of digital twins, representing physical assets, provides the possibility to leverage data to enhance and replace the conventional verification and validation efforts undertaken by industry stakeholders. Digitalization, new technologies, algorithms, and artificial intelligence (AI), incorporated in digital twins, can be used to execute effective verifications. When such digital twins have proven to provide genuine and trustworthy evidence, the evidence can be used in assessments towards specified acceptance criteria, and issue, maintain, and renew certificates. Some parts of the assessment itself may even become automated through the use of algorithms and AI solutions, further increasing the importance of the rigor and intensity with which these digital twins must be qualified and assured. This paper is developed in order to support the development of trustworthy digital twins for data-driven-verification (DDV) systems and methods. Use of digital twins should be acceptable as long as they provide the same, or higher, level of assurance as the traditional methods. DDV also aims at reducing non-productive time, costs associated with surveyors attending the physical asset, redundant verification activities, and the knowledge sharing, and transfer burden imposed upon the asset organization.
Beyond Watch Circle Alerts: A Case Study in Mooring Failure Detection Using GPS Position Monitoring Data for a Deepwater Spar
Authors: Jayasinghe K. , Thomas C. , Eassom A. , Kilner A. , Guha A. , Ryu S. , Depena R. K. , Lee D. , Xu W.
Published: April 2024

Safe and reliable access to offshore energy, whether it be through hydrocarbon or renewable sources, often requires floating infrastructure that is held on station by well designed, well installed and closely monitored mooring systems. The bounds of what is possible with mooring integrity monitoring technology has expanded in recent years, providing stakeholders with improved risk mitigation over the life of the floating facility.

GPS-based position monitoring systems are a common feature of offshore facilities. This paper presents how position monitoring data is being leveraged to go beyond excursion-limit alerts and achieve automated mooring integrity monitoring. The case study presented in this paper is for a deep-water spar facility that recently experienced a mooring line failure.

A numerical model was developed to represent the as-built condition of the facility and its mooring system. Static and modal analyses were conducted to characterise the response of the facility in both the intact and mooring line failed conditions. This characterisation was then used to tune an algorithm to detect mooring failures based on GPS position data for the facility.

In-field observations of GPS position data were provided to this algorithm as test data. The outputs of the failure detection algorithm using these in-field observations are presented in this paper. In addition to the algorithm being validated against an observed mooring failure, several storms were present in the data set, to test if the algorithm would raise false positive failure alerts; none were triggered.

The paper also discusses how mooring integrity monitoring can be deployed in practice as a 24/7 web-based automated system, accessible to key stakeholders both on and offshore. An outline architecture for how such a system may be connected to operational data sources is provided. Adequate consideration of data security and data integrity issues are important in the deployment of such a web-based solution and an outline of the challenges that may need to be addressed are provided.

By presenting a case study on how GPS data can be successfully used to monitor mooring integrity and reliably detect mooring failures whilst avoiding false positive alerts, this paper demonstrates an approach for improved risk visibility and risk mitigation for floating facility mooring systems, at lower cost and complexity than traditional mooring monitoring techniques.
Lean Subsea Electric Actuators for Linear Gate Valves
Authors: Kubacki M. , Pfeifroth E. , Hendrix G. , Orth A. , Duarte da Silva J. P.
Published: April 2024

Offshore resources are a major part of the world's required energy mix and are currently crucial as a source for many materials and goods used in our daily life. The production and processing of these resources mostly relies on heavy-duty machinery and infrastructure that has been proven and running for many decades. Over the years the possible technologies used for the process evolved and equipment became more reliable and compact with longer step-outs. At the same time, electric actuators were deployed to overcome the need for complex hydraulic power supply and to increase monitoring possibilities while minimizing time lags in the system's reaction.

During the deployment of innovative technologies, a focus was put on the safety performance of the actuation systems. Due to potential risks to the environment, safety remains a key requirement for upcoming unmanned and autonomous production and processing sites.

Linear valves and actuators play a critical role in subsea systems as they allow for lightweight and compact design of infrastructure. The first electric subsea actuators for linear valves were expensive, large, and non-retrievable due to complex safety mechanisms using springs. The current actuators reduced the size by replacing the springs with electric batteries, leading to higher costs to ensure minimum safety integrity level with complex subsea control modules. This dilemma splits the users in two groups: the ones who prioritize safety by springs but have to maintain the environmental risks and OPEX costs of conventional hydraulics; or the ones who prioritize electrification by subsea batteries but limit its application to fewer projects which can afford a much higher CAPEX.

An innovative solution to overcome the challenges of the industry, following the state-of-the-art developments, was needed to allow sustainable and future-proof production and processing. This enables viable business models for rising industries such as Carbon Storage and green hydrogen production and transportation. At the same time, the solution had to be designed in a way to reduce cost and increase reliability and protection for the environment.

This paper shows the simplest way to electric automated linear gate valves subsea, without compromising safety and efficiency. It explains how a portfolio of lean all-electric subsea actuators was developed and qualified, focused on cost-efficient and reliable operation, by integrating field-proven safety with an easy-to-exchange module and low-power consumption drive, designed to scale up the energy transition.
Suez CanalS Tsunami: Hazard Risk and Consequences
Authors: Sartini L. , Fiorini E. , Poggi P. , Duchini E.
Published: April 2024

In this work we review the impact of potential tsunamigenic events on the Suez Canal by means of numerical hydrodynamic simulations. To do this we selected three possible seismic sources affecting the area of study and able to trigger tsunami, two of which located in the eastern Mediterranean region and one in the Gulf of Aqaba. The selected sources reviewed and characterized to provide the input to the hydrodynamic analysis are the Lebanon Thrust Fault, two fault segments of the Cyprus Arc and the Evrona and Elat faults (Dead Sea Fault system).

Tsunami event due to Lebanon Thrust Fault impacts the Nile Delta and propagates into the Suez Canal with the formation of long sub waves with a maximum water level reached at Port Said after 2 hours and a half from the beginning of propagation.

Tsunami generated by seismic events due to major fault systems belonging to the Cyprus Arc affect Port Said with a maximum water level reached at about 3 hours and a half after the seismic event.

Finally, simulations developed considering as seismic source the Evrona Dead Sea Fault, located in the Gulf of Aqaba, reveal that a significant water level increase is observed along the entire Canal at about six hours from the beginning of the tsunamigenic event.
Wax/Hydrate Flow Assurance of North Sea Pipeline-Riser System Using Integrated Production Modelling
Authors: Bassey B. O. , Cunningham P.
Published: April 2024

Flow assurance problems usually impede fluid transfer across process facilities especially in low-temperature regions, where oil and gas produced contain more wax as fields mature, and hydrates form at certain temperatures and pressures in facilities transporting acidic gases produced along with hydrocarbons. This study undertook a mechanistic, compositional modelling of a subsea gas condensate pipeline-riser system in the Norwegian sector of the North Sea. The objectives were to forecast wax and hydrate problems; estimate the operating conditions necessary for formation; predict their impacts on facility throughput, well deliverability and reservoir performance; and inform the design of mitigation schemes to enhance flow assurance, production optimisation and asset integrity. Integrated production modelling (IPM) was deployed to process data extrapolated from the literature through a graphical user interface (GUI) that links different specialist software packages within the suite and considers the entire asset as a total production system from reservoir to point-of-sales. Fluid composition data from crude assays was fed into PVTp to generate the required PVT data, which was imported to GAP along with process parameters to predict wax and hydrate deposition in the pipeline-riser system. The GAP model was then connected to RESOLVE to run manual and automatic mitigation programs for wax and hydrate deposition in the system. Predicted data obtained were plotted against relevant functions to analyse the effects of these issues and the modelled mitigation schemes on production and asset integrity. A critical analysis of manual and automatic mitigation designs for each of wax and hydrate modelling is provided. Wax risk was detected by GAP at the pipeline section connecting two wells, while hydrate risk was detected at another pipeline section. Two sections were found to indicate both hydrate and wax risks. A proactive approach to wax-hydrate monitoring was thus recommended to enable the detection and troubleshooting of other production issues before they escalate. Though the present tools are based on steady state flow, they should find application in facilities operating in mature fields with declining production rates that approximate the flow regime of the simulator. The acquisition and incorporation of algorithms from dynamic simulators was also advocated to enable composite models to be built by future research and simulations run in the more practical transient state as the IPM suite undergoes regular upgrades. No previous study in the literature has been found to report the use of the modelling tools of this paper for wax-hydrate flow assurance. This study is hoped to provide unique approach to integrated flow assurance from reservoir to point of sales; a key advantage of IPM. The recommendations had informed the development of a transient simulator by the software provider.
Standardization of Flexible Pipes – Where Flexibility Matters Most
Authors: Gasparetto V. , Loureiro W. C. , Dias M. A. R. , de Oliveira J. G. A. , de França A. B.
Published: April 2024

The work presents an unprecedented standardization effort within the flexible pipe industry, that allows flexible pipe manufactures to still use their best design for each case while allowing the projects the flexibility to select pipes from a list of already qualified and ready-to-manufacture pipe structures. Over 2000 km of standardized flexible pipes have been procured by Petrobras with these standardization rules, with over 500 km being purchased annually.

First, this work presents the historical evolution of flexible pipe standardization by Petrobras up to the current stage, addressing the interactive process of standardization definition, its challenges, how the company is applying it in brown and green fields, and the benefits that it can bring to the market and oil and gas industry.

By looking into the demand of flexible pipes within brown and green fields in development, a large number of functional requirements can be seen: water depth, fluid conditions and topside and equipment interfaces show a great degree of diversity. The impact of each of these functional requirements in the manufacturing and cost of the flexible pipes was evaluated to minimize the cost and the number of design targets, thus creating a fixed menu of pipe types to be selected for each project, reducing procurement, engineering and manufacturing time. This has been a constant process with iterations over time.

After several iterations of the optimization process, four groups of target design conditions were created: a set of structures for brown fields, a set of structures for the current developments and two sets for the future projects, to identify qualification efforts and development opportunities.

Subsea project engineering is also facilitated by a pre-defined set of pipes. Standardization allows for a given pipe to be used in any give well, with minimum additional engineering, and may rely on automated analysis that consider the database of pre-defined structures. For ageing assets, replacement pipes are also readily available, minimizing downtime when risers reach their end of life. Multiple tasks within the subsea project development process are also easily automated through this list of pre-defined pipes, streamlining the process and accelerating deployment.

Standardizing the requirements for projects also allows the market to prepare for and qualify pipes in advance. With the clear target in sight, from Petrobras and from other operators, suppliers may identify the common technological gaps and tackle them with R&D support from the operators. The next projects will follow the same trend.
Interdisciplinary Strategies for Scour Risk Mitigation in Offshore Wind Foundations
Authors: Komolafe O. , Berger W. , Metz Z.
Published: April 2024

As offshore wind assumes greater importance in global renewable energy, scour undermining the foundations of these structures becomes a critical concern. The issue of scour demands proactive solutions to ensure the durability of offshore wind turbines, considering the shift to sustainable energy across the globe. This paper outlines an integrated strategy to mitigate scour risks using interdisciplinary approaches. Details will be provided on how scour degrades foundation integrity and a review of current geotechnical engineering solutions, supported by case studies. The influence of currents, waves, and sediment transport on scour is highlighted with computational modeling to simulate these dynamic processes. Big data analytics is explored to enable rapid automated risk assessments using advanced numerical algorithms and predictive analytics. The study also analyzes existing mitigation measures and proposes enhancements to preparedness, rapid response, and training. Current regulations are reviewed for compliance, with recommendations to update offshore industry standards. The potential to apply these techniques more widely, including in the oil and gas sector, is discussed. Future challenges, including environmental changes and technical limitations, are noted. Additional research avenues include enhanced scour monitoring and new foundation designs. In summary, this paper synthesizes key learnings, recommends pragmatic next steps that can be taken, and forecasts the evolving scour risk outlook as the shift towards offshore wind expands exponentially. A collaborative and proactive approach engaging disciplines across offshore geotechnical engineering and marine geosciences is advocated to safeguard the vital role of offshore wind in sustainable energy, accounting for the complex challenges of dynamic open ocean environments. The proposed recommendations will enable offshore wind power to successfully become an integral part of how energy is generated around the world, thus supporting a green energy future that is sustainable and eco-friendly.
Gentle Driving of Piles: Field Observations, Quantitative Analysis and Further Development
Authors: Tsetas A. , Kementzetzidis E. , Gómez S. S. , Molenkamp T. , Elkadi A. S. K. , Pisanò F. , Tsouvalas A. , Metrikine A. V.
Published: April 2024

In this paper, the main findings and developments pertaining to the Gentle Driving of Piles (GDP) method are presented, addressing various aspects of monopile installation. GDP introduces an innovative vibratory installation method for tubular (mono)piles, utilizing simultaneous low-frequency axial and high-frequency torsional vibrations to enhance the pile installation performance, while curbing underwater noise emissions during driving. To support the earliest development of the GDP method a multi-fold research programme has been carried out, including laboratory experiments, field testing, and advanced numerical modelling. The first field tests at the Maasvlakte II site (Port of Rotterdam, The Netherlands) successfully demonstrated the use of GDP in sandy soil in terms of (enhanced) installation as well as post-installation response to lateral cyclic loading. Furthermore, numerical modelling work was undertaken, addressing the aspects of drivability, vibro-acoustics and lateral response to cyclic loading. This paper provides novel insights into sustainable monopile installation, addressing challenges related to installation performance, lateral loading response, and vibro-acoustics. GDP emerges as a propitious solution for future offshore monopile installation, contributing to the ambitious goals of the offshore wind sector.
AI Camera System for Real-Time Load Concentration Estimation
Authors: Jing Haorong , Ozbayoglu Evren , Baldino Silvio , Holt Calvin , Ruel Francois , Wang Junzhe
Published: April 2024

This paper presents an innovative study that optimizes drilling operations by integrating advanced camera systems and computer vision image processing techniques. The core objective of this research is to monitor and quantify the drilled solids transported to the shale shaker in real-time. By employing a sophisticated camera system equipped with AI-based image processing capabilities, this study introduces a groundbreaking approach to estimating the concentration of drill cuttings as a function of time directly at the drilling site. This methodology aims to accurately measure the shaker load, thereby facilitating estimating time-dependent cutting concentration during drilling operations. The research enhances the system's precision by comparing the actual cuttings concentration measured from the loop with the estimates derived from the processed camera images. This comparative analysis aims to validate the effectiveness of the camera-based system and its potential to revolutionize the accuracy and efficiency of drilling operations. The findings of this study are anticipated to contribute significantly to increased operational efficiency in the oil and gas industry, marking a substantial step forward in applying AI in field-based drilling analytics.
Repurposing Western Australian Gas Network for Hydrogen Transportation - A Case Study of Telfer Gas Pipeline
Authors: Sofian Mohammed , Haq Bashirul , Alshehri Dhafer , Rahman Mohammed Mizanur , Zaman Ehsan
Published: April 2024

Blending hydrogen with natural gas (H2-NG) in pipelines is one of the pragmatic solutions to lower carbon emissions from natural gas usage. This strategy entails incorporating a defined percentage of H2 into established NG networks. This work evaluates the potential of H2-NG blending in the Telfer Gas Pipeline (TGP) – a part of the Western Australia transmission network. The effect of increasing H2 fraction on pressure profile, corrosion, and erosion along TGP was addressed.

The pipeline model was developed and validated using PIPESIM-Net software. The tested gas mixtures were calibrated with comparable studies, while the pipeline model was validated with the real operating conditions of TGP. Then, a thorough sensitivity analysis was performed, investigating the impact of varying H2 concentrations. The molar fraction of H2 in the gas mixture increased from 0% to 80%, with a 10% step.

The inclusion of H2 substantially increased the pressure profile at both the TGP's mainline and delivery nodes (sinks). This rise in pressure resulted from notable reductions in both density and viscosity as the H2 fraction increased, contributing to decreased hydrostatic and frictional pressure losses along the pipeline, respectively. Thermodynamically, the compressibility factor reached unity when the gas composition contained 80% H2. The heightened pressure in the pipeline caused increased corrosion rates, although the erosional velocity ratio exhibited a slight decrease with higher H2 content.

This analysis offers critical insights into the impact of H2 concentration on the system, providing a comprehensive assessment of potential risks and opportunities of H2-NG blending in transmission networks.
Next Generation Bulkheads for Pipe-In-Pipes: Story of a Fast-Track Technology Development from Inception to Offshore Operational Testing
Authors: d'Huart P.-E. , Hallot R. , Roland P.
Published: April 2024

This paper discusses the development of next-generation bulkheads for Pipe-in-Pipe, aiming to replace forged bulkheads with cheaper and safer mechanical stoppers. The process started with an innovative mechanical design based on wedges, utilizing alternate plastic materials instead of steel for enhanced safety and improved thermal performance. The development included the selection and qualification of the supply chain, prototype production, mechanical testing, and design improvement for the final Scale 1 production.

The versatile and agile development process allowed for quick testing and pivoting of use cases, resulting in a fast-track development completed in less than three years. The wedges demonstrated excellent mechanical resistance, exceeding expectations. Operational benefits included a much safer and hands-free setup methodology, a 6-fold reduction in bulkhead setup time, and a 20% increase in overall productivity for laying Pipe-in-Pipe flowlines.

The use of polymeric bulkheads also addresses thermal conduction issues associated with steel, reducing thermal losses, and enhancing the overall thermal performance of Pipe-in-Pipe. The paper emphasizes the novelty of using plastic-based wedges, with a patent published in 2020, marking the first qualification of such a system for offshore installation. The results and observations presented contribute valuable information to the petroleum industry, offering a safer, more efficient, and thermally optimized solution for Pipe-in-Pipe applications.
Pilot-Scale Demonstration of New Compact CO2-Capture Technology at Elevated Pressures, and Design of Large-Scale Demonstration
Authors: Isdahl O. M. , Shamshiri S.
Published: April 2024

Compact, and lightweight solvent-based CO2-capture technology is developed. The technology has undergone pilot-scale demonstration and extensive testing. The aim of this research is to systematically quantify the effects on the process variables associated with pressurized CO2-capture of flue gas streams or other process streams, encompassing both low and high CO2 concentrations. The objective is to verify the technology and to obtain the data necessary for the design of a large-scale demonstration plant, capable of capturing CO2 under real operational conditions. Results from four months of operation of the pilot are presented. The novelty of the technology lies in the CO2 absorption aspect of a solvent-based capture technology, utilizing static mixers and separators for contacting the gas and liquid phases. Consequently, the pilot scale absorption unit has been integrated into an existing solvent regeneration system. The solvent utilized in the demonstration is a 30 wt% monoethanolamine (MEA) solution. Pressurized capture is benchmarked against previous research conducted using the same regeneration unit but previously done with a conventional atmospheric absorption column. The research project has performed extensive testing under atmospheric conditions, yielding substantial amounts of comparable data between conventional atmospheric CO2 capture and the new technology both at atmospheric and pressurized conditions. The results show a greater than 95% CO2 capture rate both for low (2.5 vol%) and high CO2 concentrations (10 vol%). Further, the testing shows significant improvement of mass transfer of CO2 between the phases, and reduced size requirements both from a physical aspect related to dimensions of gas piping, but also with regards to the size of the absorption equipment (i.e., Mixer, separator, and piping in between those two elements). The results obtained have been sufficient to design a large-scale demonstration plant, and dimensions, size, cost, energy requirement and OPEX considerations of a full-scale system will be presented. The novelty of the technology revolves around developing a compact CO2-capture system that can be retrofitted into facilities that has existing emissions points, but most importantly, being able to enable CO2 capture on offshore installations that is not suitable for conventional technologies. The technology is likely to provide a significant cost reduction from a CAPEX perspective due to the reduced size and weight. Capturing CO2 in a compact way at pressurized conditions is likely to add great benefits. Gas turbines manufacturers are developing methods of exploiting the pressurized exhaust after the compression stage upstream expansion to facilitate high pressure CO2-capture, while preserving the energy. The presented technology can be an enabler in this market and bring down cost, size and energy consumption for gas fired power production with CCS.
Advanced Offshore Hazard Forecasting to Enable Resilient Offshore Operations
Authors: Mark-Moser M. , Romeo L. , Duran R. , Bauer J. R. , Rose K.
Published: April 2024

Hazards in the offshore environment can imperil successful energy operations, whether those operations are conventional, renewable, or for decarbonization. The expanding accessibility of data science and the advanced applications of machine learning (ML) models creates an opportunity to assess potential hazards and the infrastructure they impact. We present a use case demonstrating the combined application of published ML tools to U.S. federal waters of the Gulf of Mexico, an actively explored region for offshore energy that is affected by variable metocean conditions and geologic processes contributing to potential hazards. This paper demonstrates the streamlined use of ML tools to illuminate potential cascading risk events posed by seafloor hazards to pipeline infrastructure, as well as the hypothesized fate and transport of released material in the event of a pipeline rupture. We apply an ML-informed submarine landslide susceptibility tool (ML-LSM) which analyzes spatial features including slope and sediment type using a gradient-boosted decision tree (GBDT) algorithm to produce a susceptibility map in addition to the Climatological and Instantaneous Isolation and Attraction Model (CIIAM), an advanced Lagrangian model to predict material transport based on typical metocean conditions. These models were applied to the Gulf of Mexico to produce spatial results based on the features respective to the seafloor and metocean environments. The Advanced Infrastructure Integrity Model (AIIM) tool, which uses big data and ML models including GBDT and artificial neural networks, was applied to provide a preliminary forecast for pipeline integrity. Intersections of submarine landslide susceptibility, potential for infrastructure integrity loss, and material transport are highlighted amongst the results, which are presented spatially. The combination of these models utilized ML analytics to provide multiscale insights into potential future risks to energy infrastructure. Results of AIIM, in corroboration with various reports, show most existing pipelines are forecasted to be operating past their original design life. The ML-LSM map indicates locations with high landslide susceptibility. Comparing the ML-LSM and AIIM results, we are able identify potentially vulnerable structures that are at greater risk, or those in areas with lower landslide likelihood that may be potential candidates for lifespan extension or retrofitting to support alternative energy strategies. The results of the CIIAM model are integrated to indicate material fate-and-transport complications in the event of infrastructure rupture. Areas of potential bias and recommendations for model tuning are also discussed.
Site Investigation and Risk Evaluation Using the Spatial Environmental Assessment Toolkit
Authors: McWilliams S. , Roberts J. , Jones C. A. , Nelson T. R. , Chartrand C. , Olson S.
Published: April 2024

Presently, marine energy (ME) deployments are absorbing unsustainable costs and timelines associated with planning and permitting to get projects in the water (up to 25% of total project cost, which is more than double comparable offshore energy projects at approximately 10% of total project costs; Kramer et al. 2020; Peplinski et al. 2021). To overcome this challenge, the Spatial Environmental Assessment Toolkit (SEAT) is in development to provide the highest-quality site characterization and a priori understanding of the potential environmental impacts using numerical modeling tools and available site data to reduce uncertainty. Reduced uncertainty equates to a reduction in resources required for planning and environmental permitting and a more streamlined path to realized commercial-scale projects.

In this work, numerical modeling and mapping tools are linked together within SEAT to assess ecosystem impacts due to marine energy installations and evaluate optimal ME array layouts based on meaningful site and ME device physics. Of utmost importance is the ability of ME developers, regulators, and stakeholders to develop ME array layouts that maximize energy production, support environmental benefits and Powering the Blue Economy applications (e.g., coastal resiliency, desalination), and minimize potential undesirable environmental effects.

The SEAT is an open-source graphical user interface (GUI) that aggregates numerical model results and spatial receptor data to evaluate the potential risk of change and subsequent impact on the environment being developed for ME. The numerical models can represent the presence of wave, tidal, or river energy converters in their respective environments and evaluate device and array generated site changes in hydrodynamics (e.g., wave fields, water currents), sediment and larval dynamics (e.g., benthic, spawning habitats), and propagation of new acoustic signals (e.g., hearing thresholds).

The toolkit of linked models and site-specific receptors will ultimately allow developers to determine optimal designs for MRE deployments that maximize power performance and benefits from changes that promote project resiliency while minimizing the potential for unwanted environmental effects. The SEAT is an integrated communication tool with which regulatory agencies, stakeholders, and industry developers can effectively evaluate the complex information required for the permitting process thereby reducing the time and costs associated with the process.
Managing Uncertainties in Offshore Wind Foundation Concept Design: A Comprehensive Approach
Authors: Orihuela T. H. , Kadivar M. , Subramanian S. , Sullivan P. R.
Published: April 2024

This paper addresses the complexities and challenges faced in the early stages of offshore wind turbine foundation design. The focus is on understanding and managing the uncertainties inherent in Wind Turbine Generator (WTG) parameters, MetOcean data, geotechnical and geophysical characteristics, and clustering strategies. It explores the critical role of WTG parameters, including loading effects and natural frequencies, and their impact on foundation design. The paper also delves into the significance of accurate MetOcean data in determining environmental loads and examines the stages of geotechnical and geophysical assessments that provide valuable insights for concept design. A key aspect of the study is the clustering strategy, which optimizes the design process by minimizing the number of distinct foundation designs required, especially in large wind farms with diverse environmental conditions. This comprehensive approach addresses the varying levels of uncertainty in data and design parameters, offering solutions to balance accuracy with available information. The paper aims to guide practitioners in navigating the complexities of offshore wind foundation design, promoting efficient, cost-effective, and reliable solutions.