bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reducing Weight, Footprint, and Capital Cost of Sulphate Removal Units Using Modified Membranes
Authors: Garrote R. , Banham J. , Neculau M. , Hepp R. , Chaumien E. 
Published: September 2023

Abstract
Membrane suppliers manufacture RO (Reverse Osmosis) and NF (Nano Filtration) in spiral wound elements, being 8" the most common element size. The spiral wound element was developed in 1970 to package RO and NF material into compact, efficient, and usable unit. Over the last decades, optimization of the manufacturing processes such as robotic glue lines and automated rolling of the elements, provided incremental improvements in the ability to pack more active membrane area in the same limited available volume defined by the length and diameter of the 8" element; but as the technology became mature, the room for further packing improvements vanished and spiral element configuration has reached an optimal plateau. Available membranes in the market have mainly been optimized up to two standard offerings: a) the higher surface of 440 ft2 per element using thinner feed spacer of 26-mil, or b) the thicker feed spacer of 34-mil having 400 ft2 per element. System designers decide on either of the optimizations depending on the feedwater and pretreatment quality, being the high surface of 440 ft2 elements reserved for "good" feedwaters. This optimal plateau drove the market at least over the last decade where all new models launched offer improvements in either rejection, permeability, fouling resistant or robustness. However, all these new products have not varied in packing density that remained unchanged.
Thanks to innovation in materials science, a new generation of RO and NF elements has been developed using unique New Thin-membrane technology. This unique technology allows for significative improvement in the packing density, offering the possibility of taking advantage of the combination of both forementioned optimizations in the same membrane element, that is the high active surface area of 440 ft2 and the 34-mil feed spacer. Alternatively, the technology allows to keep the thinner 26-mil feed spacer but boosting the active membrane area up to 510 ft2 per membrane element. This new technology has already been marketed and since 2020, several systems have been in service with the new generation elements. In this paper we discuss the advantages of using the new generation elements as experienced in the replacement of older generation elements used for Sulphate Removal in FPSOs in Brazil and other regions.
Pre-Installed Cable Protectors Will Save Time and Improve Safety While Running Completions
Authors: Bibby J , Brodie A , Fiorucci J 
Published: September 2023

Abstract
This paper will demonstrate the improved safety advantages, rig time savings and the associated cost reductions available by using pre-installed cable protectors during run-in-hole (RIH) operations for completions where downhole cables are at risk of damage. Pre-installed cable protectors can greatly reduce the number of personnel operating in the ‘red zone’, eliminate costly shipping logistics and reduce the amount of time needed installing cable protectors on the rig floor, thus providing safety benefits and improving RIH timing.
Acoustic Sand Detector Virtual Calibration: Methods and Validation
Authors: Barton N. , Constable K. , Nysaeter K. , Syslak H. 
Published: September 2023

Abstract
Acoustic Sand Detectors (ASDs) have been widely used on topsides and subsea flowlines to measure sand production for the last 25 years. Essentially, ASDs are filtered microphones, strapped onto a bend or tee, that detect ultrasonic noise generated by impacting sand.
ASDs are typically used either to detect the presence of sand or to quantify the sand rate. In the former case the well will typically be choked back when sand is present. This approach has the disadvantage that production may be curtailed even when sand production is too low to be problematic. Alternatively, the ASD could be calibrated by means of a sand injection. Once calibrated the ASD can output the sand rate in grams per second, allowing the operator to judge whether the sand rate justifies choking back the well. This strategy can significantly boost production rates. However, sand injection is not always feasible for topsides ASD installations and has never been done subsea (to our knowledge).
This paper summarises work that attempts to address this limitation. A correlation was developed that calculates ASD calibration coefficients without the requirement to perform a sand injection. It works on the assumption that sand noise increases when fluid noise increases, with additional corrections for various multiphase flow effects. The correlation was developed using historical data from laboratory tests and from offshore sand injections. It was then validated against additional historical topsides injection data from platforms in the North Sea. In this initial assessment the correlation was validated against approximately 800 data points.
One of the main potential applications of the correlation is to help estimate sand rates using data from subsea ASDs. Unfortunately, no suitable subsea data was available that could confirm the validity of the correlation, but it was shown that ASDs respond differently when installed subsea. Subsequently, laboratory flow loop testing was performed with ASDs installed on a pipe submerged in a pool. This confirmed that the correlation has a similar accuracy for both topsides and subsea ASD installations. The correlation is currently being trialed by an operator with a view to using it as a tool within their overall sand management strategy.
ASDs are widely installed, but their output is often poorly understood or misused. This paper outlines the correlation methodology and identifies the possibilities and limitations of other approaches. The validation and testing exercises also flag a range of other issues when using ASDs; the effects of poor installation; how subsea acoustic attenuation affects ASDs; and important considerations when performing sand injection calibrations.
Mechanical Umbilical-Less Installation of Tubing Hangers
Authors: Hansen F. N. , Saelen C. 
Published: September 2023

Abstract
Operators with subsea developments on the Norwegian Continental Shelf have the last 20 years aimed for better efficiency and reduce equipment and personnel needed on the rigs in relations with subsea completions. Drivers have been reducing HSE risk, reduce need for modifications on the rigs to accommodate for subsea related equipment such as reels and workover control systems, and reduce cost, rig time and emissions. Many measures have been implemented such as removing need for landing string and wireline operations with deep-set pump-open or disappearing barrier plugs, installing Intervention and Workover Control system (IWOCS) to operate all systems suppliers’ tools from same unit, use of ROV Workover Control System (RWOCS) subsea HPUs to control the Xmas Tree (XT) to remove the tree running tool (TRT) umbilical, developing a hydraulic-electric remote operated control system communicating on wired drill pipe to the tubing hanger running tool (THRT) to remove the need for THRT umbilical and IWOCS, to mention some.
This paper describes one of the last inventions; a mechanical tool for installation of tubing hangers (TH) that also removes the need for remote communication and hence dramatically reduces complexity and potential for faults. The mechanical tubing hanger running tool is called THRUT and has been developed by CCB Subsea in cooperation with Equinor. First umbilical-less subsea completion ever run with a THRUT was successfully conducted on the Equinor's Heidrun field on well E-2 from the Transocean Encourage drilling rig in March 2022. Following the first well, the THRUT has been run on 8 more wells for Equinor and 3 wells for Norske Shell. The tool concept is accommodated to interface to any kind of subsea horizontal XT (HXT) systems delivered by either Aker Solutions, TechnipFMC, OneSubsea, BakerHughes, or other system suppliers. And also, the tool is operated offshore by the subsea system supplier in charge of the subsea completion, no extra personnel from CCB Subsea is required offshore. Result is an efficient and robust tool with profile of low risk, low cost and less personnel needed.
The paper describes the philosophy and requirements for the system design, the device functioning, and method for mechanical umbilical-less installation of TH in subsea HXTs, and also summarizes the most important results and operational experiences with regards to the advantages related to HSE, time, cost, personnel need, logistics and rig interface.
Biocatalysis Approach for Affordable and Sustainable Green Hydrogen Production
Authors: Laddha Chetan 
Published: September 2023

Abstract
Green Hydrogen is widely acknowledged as one of the important pillars for decarbonisation of hard-to-abate sectors and to transition the global economy to Net Zero. The current priority in the energy sector is to rapidly establish and scale a green Hydrogen based energy value chain that meets three core objectives: affordability, sustainability and security of supply, also referred to as ‘Energy Trinity’. Green hydrogen is produced from electrolysis of fresh water through technologies such as alkaline electrolyser, PEM (proton exchange membrane), and SOEC (solid oxide electrolyser). The production of green hydrogen from water is an energy intensive process, due to the high thermodynamic stability of water molecules. The cost of producing green hydrogen at scale is large proportional to the cost of renewable electricity. This requires green hydrogen production basins to be located close to regions/ geographies with access to surplus and low-cost renewable electricity, such as Australia, Middle East, Norway, Scotland and Chile.
The current cost of green hydrogen in the UK has a 5-10 times cost premium as compared to fossil fuels.
The primary inputs from green hydrogen production through electrolysis technologies are renewable electricity and freshwater. There has been an increasing concern globally on the availability and preservation of water resources. There are publications from water companies in the UK citing that the supply of constant fresh water supply for industrial applications such as green hydrogen production cannot be guaranteed under rapidly changing scenarios of climate change. There is a potential to set up large scale desalination plants to meet the fresh water for hydrogen production, however the large quantities of discharge water with high brine concentration might pose environmental hazards to marine habitat.
This calls for alternate technologies to be developed which addresses the freshwater dependence for green hydrogen production and the significant green premium on cost structure.
The paper describes a novel biocatalysis approach for production of green Hydrogen from wastewater, without requiring electricity input.
LOHC Business Models in Real-Life Trials – Reducing Cost and Risk in a North Sea Context, in Particular Through Repurposing Existing Infrastructure
Authors: Gilmore K. A. , Iliffe M. E. 
Published: September 2023

Abstract
The need for deep decarbonization has never been more evident or urgent than right now. The world is far off the Paris Agreement's commitment to limit global warming to well below 2 degrees Celsius. Countries representing more than 70% of global GDP have committed to reaching net zero, and there is increasingly consensus that hydrogen will play an important role in the decarbonisation of multiple sectors, including heavy goods vehicles, industrial feedstocks and high-grade industrial heating – applications for which there is no other decarbonization solution at present. There are also opportunities to use hydrogen to balance electrical energy systems, and to transport energy globally in a way that is not currently possible with electricity. Given these high potential applications, hydrogen is estimated to provide between 12-22% of the world's final energy demand by 2050.
However, there are significant commercial gaps currently in the hydrogen value chain, in particular the lack of a solution for large scale storage and transport of hydrogen. Hydrogen as an energy carrier has a relatively low volumetric energy density. A solution for transporting hydrogen at scale between global low-cost production and demand centers is therefore needed.
The growing hydrogen economy represents a major opportunity for energy producers - many of whom have existing skills and infrastructure which can be repurposed for this sector.
Lessons for Successful Digital Twin Implementation in Operations
Authors: Kennedy R. 
Published: September 2023

Abstract
With significant excitement about digital twins in industry, there is often far too much emphasis put on the technology – overlooking the fact that it is just one ingredient in a successful digital transformation. This paper will present an approach to planning, implementing, and sustaining operational digital twins, that is designed to maximise the asset owner's return on investment by putting the necessary focus on the people, process, and data elements, as well as addressing the technology.
A review of project lessons and industry findings will be presented to outline common challenges experienced during digital twin projects. Based on this, a structured digital twin methodology for operating assets has been designed to help address and overcome these challenges. The approach will enable asset owners to take a more holistic view of digital transformation using digital twins, enabling them to maximise the return on existing investments and drive lasting change – and value – through their asset operations. The digital twin methodology is delivered in three stages: advisory, implementation and value realisation.
During the advisory phase, the vision, business outcomes, objectives and value drivers are defined. Working closely with operations teams, use cases for the digital twin are identified, screened, and grouped to form strategic initiatives. Initiatives are then developed to define the required investment and forecast return, before being prioritised and sequenced on a strategic roadmap.
The implementation phase is performed using an agile, value-driven, and user-centric approach, which utilises a design-thinking process. Through each step, the people, process, technology, and data aspects are specifically considered and evaluated.
During the value realisation phase the technology, data and associated business processes are maintained, and users are engaged to guide continuous improvement and future use case development. The ongoing benefits are tracked to support continued investment.
Two detailed case studies will be presented to illustrate the digital twin methodology in practice, detailing the challenges faced, and the outcomes achieved.
Developing a Strategy for Site-Level Methane Emissions Monitoring to Meet OGMP2.0 Level 5: A Case Study
Authors: Heggo D. , Balcombe P. 
Published: September 2023

Abstract
The voluntary Oil and Gas Methane Partnership (OGMP) 2.0 framework requires companies to improve their methane measurements and reconcile between source-level (bottom-up) monitoring and site-level (top-down) measurement campaigns. This study presents an analysis to develop a multi-site strategy for meeting level 5 OGMP2.0 standards. The framework involves a series of site assessments based on the available bottom-up emissions estimates, local weather data that impact measurement conditions, and emissions dispersion modelling. To demonstrate the developed framework, two site-level methane monitoring techniques (drone A and B) were selected for analysis of suitability on 6 gas assets, both offshore and onshore.
Firstly, bottom-up emissions estimates are collected for each site and assessed for data quality. The distribution of emissions for each source is used to develop a Monte Carlo simulation that analyses the benefit of conducting increased numbers of site-level measurements for reconciliation.
Weather has a critical bearing upon the capacity to conduct many top-down measurements. High-resolution weather data was synthesized for each region to determine the likelihood of a successful site-level drone measurement on each day during the year-long study period. A dispersion model derived using computational fluid dynamics was used to integrate bottom-up and weather data to shed light on potential estimation uncertainties from conducting site-level measurements across different days in the year. The results show that weather plays a very important part in predicting the success of a measurement campaign and the technique selection, with some sites having particularly restrictive rain and wind patterns. Sites with lower emission rates and high winds will not suit a site-level technique that monitors at distances of &gt;250m. The quality of the bottom-up emissions estimations is also a vital parameter in decision making and data analysis: where the time resolution of source data is poor, it is not recommended to conduct several site-level studies as there is little potential for reconciliation.
Impact of Environmental Conditions on Safe Depressurisation of CO2 Pipelines: A Discussion on Design and Feasibility
Authors: McKay C. , Stokes S. , Shirani F. 
Published: September 2023

Abstract
Designing pipelines for CO2 transport comes with unique challenges when compared to conventional oil and gas transportation systems. One of which is the proximity of the CO2-rich fluid phase boundary to typical operating conditions. There are also significant risks specific to non-routine, planned operations which cross this phase boundary - such as depressurisation. This paper discusses how changes in environmental conditions can impact the safe depressurisation of CO2 pipelines.
During depressurisation of a CO2 pipeline, cold temperatures are a risk due to the high Joule Thomson (JT) coefficient of CO2-rich gas. When the contents of the pipeline transition from dense to gas phase, heat will also be absorbed from the system's surroundings to supply the latent heat of vaporisation. The combination of these factors means that the surrounding ambient conditions can greatly impact the requirements for safe depressurisation. To investigate this impact, the depressurisation of three representative CO2 pipelines have been investigated using thermohydraulic modelling software, considering varying ambient conditions from Wood's project experience.
The results show that factors such as ambient temperatures, wind velocities/seabed current, and the thermal conductivity of the surrounding soil have a first order impact on the minimum temperatures expected during depressurisation. The properties of the soil, such as dryness and composition - rarely the focus of detailed environmental analysis - are noted to have a particularly high impact on the minimum temperatures expected. Depending on the minimum wall design temperatures and pipeline length, this can result in significant minimum durations required to safely depressurise CO2 pipelines. It should be noted that a reasonable and economical approach for depressurisation is to assume a constant heat flux. Such an assumption provides an order of magnitude estimate as a screening procedure to determine if a more detailed survey is needed. However, in reality, the depressurisation event would cause the temperature of the soil to drop, which impacts the heat transfer from soil to pipeline. This will be discussed on a high level, with reference made to the finite element method adopted by some industry leading software packages.
The case studies shown provide an understanding of how forecast conditions during these operations can determine system design margins and increase operational risks in very different ways depending on the installed pipeline environment. The outcome is an increased awareness on the importance of early project phase CO2 transport insights for transport assurance and asset integrity, and an appreciation of current best practice for CO2 pipeline modelling.
Hydrogen Storage in Depleted Gas Fields: A North Sea Case Study
Authors: Looijer M. , Ahmad I. , Kathel P. , Filomena C. , de Borst K. 
Published: September 2023

Abstract
This paper presents a case study on a near-shore gas field in the Dutch North Sea for a seasonal storage scenario. A subsea development was considered, connected by pipeline to an onshore processing facility. Reservoir simulations were carried out to model the mixing of the hydrogen with the in-situ natural gas and to estimate the composition of the back-produced stream and its variation during and between the individual cycles. The required sizing of the processing facilities was determined through process models, and the pipeline sizing through a hydraulic assessment. The development considered new wells, which were designed to deliver the assumed hydrogen production rate at the end of a production cycle when contamination is highest. The investment and operational costs of the complete facility were estimated as well as emissions of the storage operations.
The study enhanced the understanding of the technical scope and technology gaps; as well as the economic, environmental, and energy performance of underground hydrogen storage. It highlights main cost drivers and delivers insights into the re-purposing potential of the existing infrastructure. An example insight gained from the study was that the disposal (or utilization) of the waste stream from gas separation could pose a real challenge particularly in an offshore environment, given its intermittent character, the highly variable and partly unpredictable composition, its large flow rate, and its near-atmospheric pressure when using a Pressure Swing Adsorber for separation.
Selection of CO2 Mixture Composition for Flow Assurance Analysis
Authors: Pierre B. , Wright D. 
Published: September 2023

Abstract
Transported and geologically stored CO2 contains several impurities that depend on its source and associated capture technology. Impurities in anthropogenic CO2 can have damaging impacts on the different elements of a CCS system, which must be considered when developing a CO2 specification (Table 1). Thus, characterising all the impurities and determining the required purity of the CO2 mixture is critically important for the safe design and operation of CCS transport and storage systems.
It is important to note that CO2 specifications relate to normal operations. Short-term excursions outside of the recommended maximum concentrations for each impurity may be permissible provided they do not lead to health and safety risks and / or risks to the mechanical integrity of the asset.
Creating New Economic Reserves Using Enhanced Oil Recovery Within a Mature Offshore Field
Authors: Johnson G. , Neal A. , Lugo N. , Farthing D , Fordham A. 
Published: September 2023

Abstract
The offshore Captain Field was discovered in 1977 in the UK sector of the North Sea, it was brought online in 1997 and initially developed using field-wide waterflood using long horizontal wells and artificial lift with produced water re-injection. The reservoirs are large and homogeneous sandstone reservoirs with high porosity and permeability, and around one billion barrels of medium to high viscosity oil at 18-21° API gravity. figure 1 (a) below shows the Captain offshore facilities, with the Wellhead Protection Platform (WPP) and the Bridge-Linked Platform (BLP). The map figure 1 (b) below shows the UK sector of the North Sea, with the Captain location highlighted.