bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Development of an Enhanced Method to Predict Asphaltene Precipitation
Authors: Vargas Francisco M. , Garcia-Bermudes Miguel , Boggara Mohan , Punnapala Sameer , Abutaqiya Mohammed , Mathew Nevin , Prasad Sudha , Khaleel Aisha , Al Rashed Mariam , Al Asafen Hadel 
Published: June 2014

Abstract
Asphaltene precipitation and subsequent deposition is a potential problem in oil production because the significant costs for wellbore cleaning and the associated production loss. To better understand the mechanisms by which asphaltenes precipitate and deposit, in this work we present experimental evidence that supports the idea that precipitation and aggregation of asphaltenes is a multi-step process, where the former is driven primarily by thermodynamics whereas the latter is driven by kinetics. Under this multi-step mechanism, asphaltene precipitation is a fully reversible process. On the other hand, from the precipitated phase, subsequent aggregation and aging leads to the formation of more solid-like structures. Furthermore, we also present experimental results that suggest that the currently available commercial technologies to detect asphaltene precipitation (i.e. NIR spectroscopy and High Pressure Microscopy) might not be appropriate to detect the exact point of asphaltene precipitation, but instead they give a combined reading of precipitation plus aggregation. For this reason, the results obtained using these methods are very sensitive to the depressurization rates. The better understanding of the asphaltene behavior has enabled the development of an enhanced modeling approach based on the Perturbed Chain version of the Statistical Associating Fluid Theory equation of state (PC-SAFT EOS), which is used to predict the precipitation of asphaltenes at reservoir conditions and requires fewer simulation parameters than previous methods. A case study is presented in which our modeling technique was proven useful for the detection and correction of inconsistencies in experiments done using a bottom-hole sample at reservoir conditions.
Modeling the Properties of H2S - CO2 - Salt - Water Extreme Environments
Authors: Springer Ronald D. , Wang Peiming , Anderko Andrzej 
Published: June 2014

AbstractTo address the need to predict the properties of fluids in severe environments in the oil and gas industry, a comprehensive thermodynamic model has been developed for mixtures containing H2S, CO2, H2O, and selected salts. The model is based on the previously developed Mixed-Solvent Electrolyte (MSE) framework, which combines an equation of state for standard-state properties of individual species, an excess Gibbs energy model, and an algorithm for solving phase and chemical equilibria in multiphase systems. The standard-state properties are calculated from the Helgeson-Kirkham-Flowers equation whereas the excess Gibbs energy is expressed as a sum of a long-range electrostatic interaction term expressed by a Pitzer-Debye-Hückel equation, a virial coefficient-type term for interactions between ions and a short-range term for interactions involving neutral molecules. The model has been parameterized using critically evaluated phase equilibrium data for various binary and ternary subsystems of the H2S – CO2 – H2O – Na – Ca – Cl system and has been validated for temperatures ranging from 0°C to 300°C, pressures up to ~3500 atm and salt concentrations up to solid saturation. Furthermore, it reproduces chemical speciation in acid gas – brine systems as exemplified by the accurate prediction of pH. Because of its capability of predicting pH and activities of solution species, the model can serve as a foundation for studying metal – environment interactions in severe oil and gas environments.
International Boundary Disputes: An unfinished tale of Geology, Technology, Money, Law, History, Politics and Diplomacy
Authors: Andersen Niels , Bekker Pieter , Bishopp David , Nassif Toufic , Nordentoft-Lauridsen Sune , van de Poll Robert 
Published: June 2014

Abstract
This paper provides an overview of the history of global maritime boundary issues, mechanisms to resolve boundary disputes, and the economic potential that can be unlocked by coastal States through the exploitation of hydrocarbons trapped in areas currently unavailable for exploration and production operations.
Vast hydrocarbon reserves are tied up in areas, either underlying waters greater than 200 nm offshore or disputed by coastal States. In the former case technology in the form of deepwater drilling has made testing the potential feasible, whilst in the latter case many of the 311 or so areas in dispute are able to be tested and developed using conventional techniques.
Anything that appears to show a sovereign entity ceding control of land or sea to another country inevitably takes on a high profile in the countries concerned, which in the worst case can lead to armed conflict. It is a credit to those States that subscribe to the principles of the United Nations Charter and the United Nations Convention on the Law of the Sea ("UNCLOS") that they have reached agreement on how the economic potential trapped in disputed areas may be divided or shared.
High-profile, high-stakes disputes relating to offshore oil and gas deposits underscore the importance of the modern law of the sea, and international law generally, to the peaceful settlement of boundary disputes affecting the energy industry. Yet boundary disputes form an overlooked area of investment risk management in the energy sector.
This paper will introduce the technical and legal principles behind the solutions reached by States and will highlight some of the areas with the greatest hydrocarbon potential that have yet to be exploited as well as the areas of risk that require mitigation before investors will advance risk capital.
Advances in Power Feedthrough Connector Technology for HP ESP Applications
Authors: Nicholson J.A. 
Published: June 2014

Abstract
Emerging deep-water fields in the Gulf of Mexico pose significant challenges for the deployment and operation of subsea tree ESP systems where reliability is crucial to the economic viability of the fields. Key challenges include high initial reservoir pressures (13, 500psi), 1–2yr natural flow start-up conditions without effecting electrical integrity, 5yr MTBF for the ESP system after start-up of the pump, high horsepower pumps (1200hp), restricted space at the tree interface and the need for integrated power and controls to the pump system as examples. One of the main system components is the power feedthrough connector through the wellhead. This component has to be deployed into the wellhead as part of the Cable Hanger assembly through a marine riser and then subsequently connected to the tree Cap assembly remotely in up to 10,000ft of water depth.
For effective well control the connector systems have to maintain pressure barrier seals for the life of the well in a 15kpsi rated tree. In addition the connector system has to maintain electrical integrity under high voltage conditions and be able to be mated together consistently within the confines of the tree system. Increasing qualification standards by operators pose even greater challenges to the connector vendors as standards are driven higher.
This paper presents the latest connector technology developed by OneSubsea to meet the extreme challenges and needs of HP ESP applications in the GOM.
Ultra-High Strength Proppant Developed for Deep, Offshore Completions
Authors: Palisch Terry , Duenckel Bob , Wilson Brett 
Published: June 2014

Abstract
As the industry has moved to the development of deeper reservoirs, drilling and completion equipment have undergone significant upgrades to allow for the successful exploitation of these higher pressure, higher temperature applications. Similarly, no conventional proppant can provide the required conductivity at the 20, 000 psi closure stresses (and higher) anticipated in the formations such as those found in the Lower Tertiary of the deepwater Gulf of Mexico. With the development of these reservoirs, whether in the GOM or other offshore applications, there now exists a gap in downhole proppant performance and technology.
This paper will document and present the results of years of research prompted by deepwater GOM operators, resulting in a new proppant that has been developed specifically to meet these challenges. The step change advancements achieved by this new proppant will be presented, including technology improvements in both raw materials and manufacturing process. It will present unique proppant properties regarding shape, sizing and strength, never before seen in conventional proppants. The end results is a proppant which exhibits twice the baseline conductivity of any conventional proppant at these high stresses, and provides additional advantages with increased durability and longevity. Extensive laboratory testing has been completed to demonstrate the superior performance in harsh conditions, and will be presented.
The paper will also review the potential applications for this product, which should result in increased production rates, superior EUR, lower erosivity and reduced equipment wear. Field applications are being evaluated and will be discussed.
This paper should be beneficial to all engineers and technologists currently working in the deep, high stress offshore environments of the GOM's Lower Tertiary or comparable applications.
Deepwater Methane Hydrate Gravel Packing Completion Results and Challenges
Authors: Terao Yoshihiro , Duncan Mike , Hay Bill , Dang Le 
Published: June 2014

Abstract
The world's first subsea gravel packing for methane hydrate was conducted and production test successfully executed in the eastern Nankai Trough area off the coast of central Japan in March 2013. Methane hydrate formations all over the world promise huge energy reserves on the earth to permafrost zones in the Polar Regions, and formations within several hundred meters from the seafloor of an ocean. The formation and shallow depths create an assortment of issues that must be addressed to successfully produce this resource. The gas production from methane hydrate formation is different from conventional oil and gas formations in terms of the mechanism and the phenomena, since low temperatures, high pressures environment, and physical properties change in the formation as methane hydrate dissociation. It is important to overcome the above issues for methane hydrate production.
During the planning process, studies were completed to review the formation particle size, the low-temperature effects on tools, circulating temperature issues, the erosional considerations and potential subsidence of the formation. Various experienced processes were used and testing completed to prove the integrity of the system that utilized several nonstandard pieces of equipment and procedures. Vigorous preplanning, experienced personnel and onsite expertise enabled the people and equipment to be prepared for the procedure allowing successful variations. Post-job analysis and review of how the various products and services worked together will enable further success in the future.
This paper discusses the application of vertical open hole gravel packing in a methane hydrate production well from a floating-rig environment in the eastern Nankai Trough area off the coast of central Japan. It reviews the pre-planning process, the equipment selection, procedure recommendations and the on-job decision-making that enabled the successful flow testing.
Restricted-S Riser Configuration for Ultra-Shallow Water Projects
Authors: Dencker Claus 
Published: June 2014

Abstract
The design of dynamic riser systems in connection with floating production units operating in shallow water generally results in rather complex configurations using combinations of buoyancy elements, clump weights, tethers, anchors, and special arrangements of rigid and/or flexible structural members. These often complicated systems can be difficult to install, they may require an extended seabed lay-out area and the operation of these complex systems can be associated with a relatively high risk profile. Thus there is an incentive to develop reliable shallow water systems for harsh environmental conditions which do not have the above draw-backs.
This paper describes the development of a novel dynamic riser system (Restricted-S System) intended for use in extremely harsh ultra-shallow water applications as for example offshore Malaysia and Vietnam with a water depth of 50m or less. The Restricted-S System was developed by NOV Flexibles in connection with a FPSO field project and comprises a well-known mid-water arch (can be either fixed or dynamic) in a restricted position such that it always will be in front of the FPSO vessel bow. This special feature allows the gutter system on the arch to be positioned relatively high in the water column resulting in a significant flexibility of the riser system. In particular, this configuration enables the riser system to survive in harsh environmental conditions with large vessel offsets and large vessel pitch motions.
The detailed design of the Restricted-S System will be described including the development of a special stiffness cover for the dynamic flexible risers resulting in a highly versatile system for ultra-shallow water fields thus enabling the development of challenging prospects with special high wave-height to water-depth ratios. The dynamic analyses of the Restricted-S concept will be compared to model test results thus demonstrating its superior capabilities compared to other configurations. Finally, the leanings from the successful field installation of the Restricted-S System will be addressed.
Advances in Predicting Pipeline Embedment Based on Assessment of Field Data
Authors: Bruton D.A.S. 
Published: June 2014

Abstract
This paper reviews the current methodology for assessing pipeline embedment against field data, where embedment levels were under-predicted leading to an unconservative design. An updated model is provided for predicting pipeline embedment. One important principle behind this new approach is to define the operative soil strength, based on reconsolidation of the remoulded soil beneath the weight of the empty pipe during the intervening period between laying and flooding. This approach is based on pipeline embedment data from the field, which has demonstrated that soil around the pipe can become fully remoulded during installation. Therefore, embedment in the flooded condition should be assessed using an operative strength from reconsolidation, rather than the intact strength, which is current practice. This paper also provides current equations that improve the prediction of embedments over one-half diameter, by proposing methods to take account of the increasing buoyancy with depth, the reducing influence of heave mounds and modified penetration resistance at deeper embedments.
Pipeline embedment is a fundamental input to the assessment of pipe-soil interaction, which is the largest uncertainty faced in the design of pipelines subject to lateral buckling and walking phenomena. However, pipeline embedment is notoriously difficult to predict due to the inherent uncertainty of the installation process. Improving the prediction of pipeline embedment is critical to reducing the range of predicted pipe-soil responses in design.
A current project has compared high quality observations of pipeline embedment from an earlier phase of the same field development, against predicted embedments using more recent, high quality soils data from parallel pipeline routes, including fully remoulded soil strength from cyclic penetrometer testing. While current design approaches were under-predicting embedment levels, leading to a potentially unconservative design; this updated methodology provided a much-improved match to actual embedment data. The revised model was successfully verified against measured levels of pipeline embedment and is now being used for the design of future pipelines in the area, with improved certainty and easing of the design challenge.
Under-predicting pipeline embedment could be critical to design integrity. The methodology presented in this paper has the potential to improve assessments of embedment and avoid unconservative pipe-soil responses on future developments.
Art, Science, and Engineering of Managing Offshore Field Development Economics and Risks
Authors: Chaudhury Gautam , Whooley Alan 
Published: June 2014

Abstract
Decent profit margins enjoyed by the oil industry are mainly due to inexpensive wells of the past. Exploration, development, and production costs have escalated to a level where small to medium size offshore fields are challenged to be economically developed. Each opportunity comes with its own unique constraints requiring adaptive and flexible applications from a variety of processes and systems. The art of field development engineering requires linking interactive and integrated flow of information, best practices, lessons learned, and risk management across all disciplines. This starts with reservoir evaluation and development through surface facilities and transport systems, and production management. Further considerations include finance, procurement and contracting strategy, equipment standardization, and decommissioning. Success of economically challenged field development depends on an experienced team with deep understanding of each respective domain and appreciation in interfacing disciplines. Such a team using a systematic approach challenging each constituent system and process in the field development procedure chain will help identify an optimum development plan.
In this paper, the strategy, technology, and step changes necessary for successful development of economically challenged fields are identified. The inter-dependence between sub-surface, drilling and completion, and surface facilities including production and operations are established in relation to cost, safety, and risk management. This paper will discuss a systems approach for prudent selection of all surface facilities and drilling and completion design taking due account of reservoir uncertainty.
The primary focus of this work is deep water fields of Gulf of Mexico (GOM) with strong analogs for application in other regions of the world including regional socio-political impact. High level discussion on the main drivers of the selection of deep water platforms, subsea architecture, and risers are presented.
Underwater Monitoring Network
Authors: Brevik Arild 
Published: June 2014

Abstract
This paper presents current technology and research activities related to underwater monitoring. Main focus is directed towards the wireless solutions, built with basis in underwater transponder technology where wireless communication is implemented through acoustic communication. The communication network described is a multi-hop network with autonomous handling of critical tasks as signal routing, and capable of handling both stationary and mobile sensor node within the network.
Sensornodes in the network is built by interfacing various subsea sensors to the network communication transponders or AUV's. R&D is also including a cabled infrastructure that can be used together with the wireless solution. Different sensors are selected based on the application targeted, like acoustic sonars or dissolved hydrocarbon sniffers for subsea leak detection. The goal for these R&D activities is to develop and test a versatile and scalable system that can be tailored to different applications, including environmental, military or surveillance in order to effectively provide real-time subsea data to topside.
A Dry Tree Semisubmersible Floating Production Unit Alternative for Field Developments
Authors: Korsnes J. , Noce R. 
Published: June 2014

Abstract
This paper presents the main design and performance characteristics of the Octabuoy® Classic (Octabuoy) for field developments. The focus of the paper shall be on evaluating the Octabuoy's performance when it comes to its value as a dry tree floating production system with optional drilling capability. The value is measured in terms of floater's robustness and flexibility for said applications. In turn, robustness and flexibility are achieved utilizing low-motions hull design, wide range topside load carrying capability the use of standard riser and wellbay components for different water depths. Results and corresponding conclusions of analyses aimed at determining the technical feasibility and economic viability of the Octabuoy hull for field developments in various regions of the world, water depths, drilling options, and payloads will be included. The Octabuoy is the first dry tree semisubmersible platform, which has been sold and built. It has undergone extensive numerical analyses and model testing, which indicate that the Octabuoy's deep draft and overall hull geometry are instrumental in ensuring superior performance and cost effectiveness. The associated minimal motion characteristics and the design of the Octabuoy allow for flexibility in the selection of riser configurations (traditional top-tensioned production risers or SCRs); a variety of installation options (quayside, offshore heavy lift, float over); use in both benign and harsh environments; drilling options; and relocation of the platform from a depleted field to another field.
Novel Dry-Tree Semisubmersible Solutions for Deepwater Marginal Field Development
Authors: Mansour Alaa M. , Kumar Dhiraj , Zuccolo Ricardo , James Jolly , Heidari Homayoun 
Published: June 2014

AbstractOften the requirements for dry—tree completion, direct vertical access (DVA) to production wells, as well as the ability to perform drilling and work-over from the production platform, due to operational, economic, or reservoir requirements, necessitate the use of Top Tensioned Risers (TTRs). Due to stroke limitations on the currently qualified tensioners’, TTRs are required to be hosted on a floating system with minimal heave response. To date, the floating systems of choice to host TTRs were Spars and TLPs, with the former being the floater of choice for water depth beyond 6,000ft.Conventional semisubmersible design has a number of significant advantages. These include provision of significantly larger and more ventilated deck area; ability to integrate the hull and topside at the quayside or via dry-mating at the fab yard; and lower risk and better economic for offshore installation operations compared to the Spars where they require upending and offshore deck lift operations. Additionally, the semisubmersible platforms are more flexible with respect to maximum payload. However, conventional semisubmersibles heave response is not suitable for TTR applications.This paper presents invovative semisubmersible designs, which provides suitable motion characteristics for hosting TTRs, while maintaining the advantages of semisubmersibles floaters.For development of marginal fields, it is essential to minimize the total cost of the project in every phase. This includes realizing the savings from using DVA to wells, adopting quayside integration or dry-mating of topside to hull and avoiding the need for offshore lift operations. These measures can be achieved by developing semisubmersible designs which provide better motion characteristics suitable for TTRs and Dry-Trees.Two state-of-the-art high performance semisubmersible designs have been presented here and evaluated for the development of marginal fields in deepwater Gulf of Mexico (GoM). These designs are the Fee-Hanging Solid Ballast Semi (FHSB Semi) and the Damper Chamber Column Semi (DCC Semi). Detailed description of these novel designs and their performance in the deepwater GoM Central region, as well as the performance of the associated TTR systems are presented. Furthermore, project risks and their proposed mitigation measures for these two novel designs are also investigated and reported.The paper concludes with discussions on the project execution plan, cost and schedule benefits when developing marginal fields using the two presented novel designs.