bluuebunny/crossref_metadata_2025_split huggingface dataset:
OPera - Offshore Power System for the New Era
Authors: Fagan Conn , Viteri Martha , Bangstein Bjorn-Harald Kristian , Langeland Tore , Borresen Sven-Erik Kristian , Vage Gjermund Kristian 
Published: June 2014

Abstract
As oil and gas companies extend their presence to remote and ultra-deep waters, one of their main challenges is to maintain environmentally responsible operations while maximizing returns on investment. Attention is directed to the increasing power demand offshore which triggers a quest for alternative and cleaner power supplies.
One proposed solution is presented through the conceptual study abbreviated OPera - the Offshore Power system for the new era. OPera consists of a highly efficient power hub and an electrical transmission system, supplying cleaner power to a network of offshore installations. To detail the OPera conceptual study, the Brazilian pre-salt area was selected as a case example.
The power hub has a gas fired combined cycle power plant that increases power generation efficiency by more than 15 percent, compared with conventional gas turbines alone. The power generation arrangement reduces CO2 emissions with approximately 40 percent. By consolidating power generation, the power hub also allows equipment to run at more optimal load. This is a major benefit, as it further reduces fuel consumption and overall emissions. The power hub is fueled by associated gas or parts of the export gas produced.
The OPera concept is highly flexible in size and configuration, making it relevant for different types of fields. The power plant consists of modular gas and steam units of 50 and 100 megawatt (MW) capacities, allowing the combined capacity to be tailored. Depending on water-depth, different platform and hull-designs can support the power plant. The power hub can connect with different numbers and types of installations, being located in different water depths.
Drill Pipe Riser Intervention System Successful Experience in Offshore West Africa
Authors: De Fonvielle Henri , Bordet Laurent , Marajh Mitra , Campbell W , Susak N 
Published: June 2014

Abstract
While offshore intervention on subsea equipment is quite common, the increasingly deeper water operations require light weight intervention systems while meeting safe and stringent operating specification. For these new deep offshore challenges, the conventional risers are becoming a more costly and less desirable solution.
Starting with a recollection of the main drivers that motivated the development of drill pipe riser intervention systems (DPRIS[i]), the paper details the technical and economical challenges in West Africa that have led to the design of such a solution. When non-productive time and financial aspects are taken into account, it makes sense to develop a dedicated system in order to provide fast and reliable intervention.
Depending on the field requirements, two different types of drill pipe riser systems using a proprietary double shoulder connection were used by operators. A first solution was developed in 1999 featuring a seal ring close to the external shoulder. Subsequently, a new solution featuring a gas-tight metal to metal seal on the pin nose was developed in order to address increasingly demanding and challenging operations.
Intensively used in West Africa since 1999, the solution using the seal ring has shown robustness and reliability while being used for several projects in Angola such as Girassol and Rosa and now GirRI. The paper draws a summary of these operations and the feedback on the field use and maintenance. Also it emphasises the successful qualification process for the metal to metal seal solution that has been used in offshore Nigeria since 2010 for the USAN project.
Use of Fast Response Vessels in Brazilian Oil Spill Response Plans
Authors: Azevedo Bruno Duarte , Possobon Rodrigo , Kammradt Patricia , Matos Michael , Guedes Diogenes , Xavier Gustavo 
Published: June 2014

Abstract
In Brazil, environmental laws define oil containment and collection as a primary strategy to oil spills originated by exploitation and production enterprises that reaches water bodies. Thus, it is foreseen a continuous equipment increase over the time, in a scaled response, always in accordance to accidental scenarios forecasted in the enterprise risk assessment. This way, minor spills, with higher probability to occur, require smaller resources, however made available in a smaller rage of time, whereas larger and less frequent spills must be attended to with strongest resources, in a larger period of time. At Brazilian maritime zones with higher exploitation and production activities the use of larger vessels, aiming to solve the worst cases, was prioritized. Such vessels are also used to respond the small and medium discharges, which could be solved by less robust vessels. The use of smaller and fastest vessels and simpler equipment to be operated allows the fleet's rationalization and a quicker and more effective response to more frequent situations. This changing also fosters economic profits (by reducing the figures and the fees paid by vessels chartering) and environmental benefits (by reducing emissions and the fuel consumption). In order to represent this situation, this paper compares the compliance with requirements from regulatory agency using an exclusive fleet of traditional boats and a fleet of traditional boats and fast response. A case study will be presented, considering a high activity oilfield on Brazilian coast.
Synergies Between Membrane Pretreatment and NGL Recovery in an Offshore Environment
Authors: Tierling Shane , Jindal Sanjeev 
Published: June 2014

Abstract
Interest has been piqued in the use of membranes for the removal of bulk carbon dioxide from natural gas in an off-shore environment because of the advantages that membranes present in weight, space efficiency and tolerance of motion. Integration on the membrane unit into the platform provides opportunities for synergies between hydrocarbon dewpointing membrane pretreatment and natural gas liquids recovery.
Optimization of the hydrocarbon dewpoint pretreatment provides tradeoffs between capital expense, operating expense, weight and natural gas liquids recovery while meeting the membrane hydrocarbon dewpoint requirement. There is an opportunity for the Owner and EPC contractor to define hydrocarbon dewpointing configuration and operating setpoints to maximize the return on investment while meeting the membrane vendor's requirements for dewpointing. Where these opportunities have been identified, direction should be provided by the project to the membrane vendor, whose focus is on the hydrocarbon dewpointing requirements and may not intimately understand all of project objectives including synergies with natural gas liquids recovery.

Introduction
Gas is becoming an increasingly important part of the global energy equation constituting 20.3% of the energy mix in 2010 which is expected to further increase to 24.7% of the mix by 2035 per WEO-2012 (2012) [Fig. 1].
Peregrino FPSO - Operation Challenges Overcome by the Use of Dynamic Simulation from Studies to Training
Authors: Heloin N. Rego , Haarklou Elon , Thiabaud Philippe , Jalby Guillaume , Schiefloe Torgrim 
Published: June 2014

Abstract
Peregrino Floating Production Storage and Offloading (FPSO) is the first heavy oil production facility moored in the Campos Basin 85 km offshore Rio de Janeiro, Brazil. The field is currently one of the largest producing offshore oil fields in Brazil with a daily production capacity of 100,000 bbl of oil, 350,000 bbl of water, and 7.3 MMcf of gas.
The development of Peregrino field, operated by Statoil, provided many development challenges, namely 14°API heavy oil and high water production rates with tight dynamic connection between production streams and produced water circulation requiring specific design and operations. The first phase of the development included two drilling and wellhead platforms linked to the FPSO with two parallel production trains.
Company relied on dynamic simulation and the Life Cycle Simulator (LCS) to master the integrated field layout. The LCS was used throughout the design phase as well as for operator training and verification of Safety and Automation System (SAS).
This paper gives an outline of the Peregrino LCS and highlights the benefits of using this powerful tool for this project. The simulator model is a comprehensive and high fidelity dynamic virtual plant that includes subsea facilities (wells, electrical submersible pumps and flow lines), two wellhead platforms and FPSO topsides process and utility facilities.
In the first phase dynamic studies were performed to validate design options on wellhead platforms and safety systems. Then the dynamic simulator was interfaced with external controller software from the SAS supplier and used to commission the SAS. It was subjected to complete shut-down and start-up tests as well as equipment and instrument malfunctions thus testing SAS in all range of operation and providing a robust operator training tool.
The simulator project has provided an increased understanding of the operational challenges prior to start-up, and helped Company in the development of the Standard Operational Procedures. First production from the field was achieved in April 2011 and is expected to continue until 2040.
Integrated 3D Acid Fracturing Model for Carbonate Reservoir Stimulation
Authors: Wu Xi , Hill Alfred Daniel , Oeth Cassandra , Zhu Ding , Gildin Eduardo 
Published: June 2014

Abstract
Acid fracturing is one of the stimulation methods used in carbonate formations and has been proved effective and economical. Because of the stochastic nature of acidizing in carbonate formation, designing and optimizing acid fracture treatment today still remain challenging. In the past, a simple acid fracture conductivity correlation was usually sufficient to estimate the overall average fracture conductivity in the formation, leading to the computation of the productivity index for fractured well performance. However, the statistical nature of heterogeneity could not be included in the modeling. Understanding the important role of heterogeneity to stimulation performance becomes a crucial step in design and optimization. In order to study the effect of this stochastic nature on acid fracturing, a fully 3D acid reaction model was developed based on the geostatistical parameters of the formation. This made it possible to describe local conductivity distribution related to acid transport and reaction process. In this study, we have developed a new interactive workflow allowing the model of the fracture propagation process, the acid etching process and the well production interactively. This paper presents the novel approach in integrating fracture propagation, acid fracturing, fracture conductivity, and reservoir simulation models in a seamless fashion for acid fracturing design.
In this new approach, the fracture geometry data for a hydraulic fracture is first obtained from commercial models of hydraulic fracture propagation, and then the 3D acid fracture model simulates acid etching and transport on the same gridding system from the fracture propagation model using the width distribution as the initial condition. We then calculate the fracture conductivity distribution along the created fracture considering the geostatistical parameters such as permeability correlation length and standard deviation in permeability of the formation. The final step of the approach is to predict well performance after stimulation with a reservoir flow simulator. The significant improvements of the new approach are capturing the geostatistical effect of the formation and modeling the acid etching and transport more accurately. The paper explains the methodology and illustrates the application of the approach with examples. The results from this study show that the new model can successfully design and optimize acid fracturing treatments.
A Novel Solution to Deepwater Logistical Challenges: Fast Supply Shuttles and High Bollard Pull AHTS
Authors: Kavli Per , Welch Mike 
Published: June 2014

Abstract
Deepwater operations are producing new challenges for operators, as production platforms get larger, and are located fueurability, leading to longer installation times. ther from shore. These platforms are now close to the limit of helicopter range, introducing greater safety concerns and limiting the cargo weights that can be carried, while conventional Offshore Support Vessels travel slowly and would take several days to reach the platforms. Higher power requirements for anchor handling duties means more vessels and more cost, or larger vessels and lower manoeuvrability, leading to longer installation times. In addition proposed maritime legislation will reduce permitted NOx emissions to levels where post-combustion clean-up will be required on diesel engines, adding cost and requiring valuable space.
This paper examines potential solutions to these challenges using a novel design of all-electric ships using LNG as the fuel and the advantages offered over conventional solutions.
The concept Fast Sea Shuttle (FSS) is a high speed multi-purpose 95m vessel capable of operating at transit speeds of up to 40 knots while still carrying considerable cargo loads and enabling rapid personnel transport in relative comfort and safety compared to current methods, and can contribute to the reduction in overall costs of personnel transportation and logistics. The concept 100m AHTS design offers a bollard pull of 380 tonnes while remaining a compact, manoeuvrable vessel. Both vessels are expected to be able to operate in sea states of 4 - 5m thereby reducing waiting time for the weather and providing improved safety for the vessel and its crew.
In addition to novel design features, the key to the high speed of the FSS, and the high bollard pull and fast response time of the AHTS, is the use of an al-electric propulsion system, combining reciprocating engine and gas turbine generator sets for fuel efficiency, using clean-burning LNG as the main fuel. This concept, making use of the high power density and fast loading times f the gas turbines, provides the most efficient solution with reduced weight to maximise speed, towing power, load carrying capability and passenger comfort, while minimizing the environmental impact of logistical operations by using ‘clean’ natural gas.
Improved Recovery Rate in Brownfield Subsea Wells Using Riserless Light Well Intervention
Authors: Karlsen Ole Eddie , Morrison Bevan Jon , Maciel Pedro 
Published: June 2014

Abstract
The combination of increasing global energy demand, known reserves being depleted, and the offshore locations of new oil and gas discoveries is pushing drilling and production into deeper and deeper waters. As a result, the number of subsea wells has increased steadily over the years to more than 5,500 by the end of 2012. Unfortunately, due to their location in deep water, interventions in subsea wells have typically required drilling rigs. Thus operators have been reluctant to perform interventions on these wells. This problem has only been exacerbated as drilling rates increase and sourcing rigs becomes more and more difficult. Thus, recovery factors are much lower—typically 10% to 30% lower—than recovery rates of dry-tree, platform-based wells. Therefore, cost-effective riserless light well interventions (RLWI) are crucial if subsea operators are to realize the full potential of 50% oil recovery (or more) from their subsea fields. This becomes increasingly true as wells age without proper maintenance.
Many opportunities exist to increase recovery rates in brownfields. From milling scale and debris to cutting tubing without using explosives to setting packers and manipulating or changing downhole hardware—all these and much more can be done with RLWI. As proof of concept, several case studies of specific interventions and the resultant productivity increases will be discussed. We will also discuss how adoption and use by North Sea operators has let them increase recovery from 36–46%. For example, Statoil estimated that in 2010, the contribution of RLWI interventions was in the range of 15 billion NOK (2.5B USD).
In addition, we will show the increasing effect pro-active interventions have on recovery rates over time, for selected Norwegian fields. Finally, we will discuss how increased use has made these operations much more routine while also providing opportunities for the technology to evolve. This is a trend that will only continue as operators request additional services in increasingly challenging environments, particularly outside the North Sea.
A Challenging Trunkline ILT Design Driven by S-Lay Installation - A Robust Design Solution Using Advanced Numerical Simulation
Authors: Large Richard , Thompson Barry , Kaliyaperumal Gnanasekaran , Cooper Philip , Zhao Tao 
Published: June 2014

Abstract
Traditionally the S-lay installation loading condition using a stinger is not considered in the structural design of a Pipeline In-line TEE Structure(ILT) during FEED, and is usually only considered during the detailed design. However in a recent FEED project exercise, the S-Lay installation loading condition was found to govern the structural design of the ILT.
Large pipelay forces and moments due to curvature are expected during installation, which required the ILT to be analysed in order to meet the structural integrity requirement during S-Lay installation. Such a design issue requires the attention of the subsea structure designer early in the design process particularly for a large diameter pipeline, in which a high installation loading is expected.
However there are several design challenges in such a design practice. The approach to estimate the pipelay loadings has to give adequate conservatism, considering the range of potential installation vessel configurations. In particular, a high bending moment at the sagbend is expected due to the large size of the pipe, which complicates the design of the ILT structure design and design optimization.
These challenging design issues were extensively explored in a recent project. Advanced numerical modelling was used to assist the design, analysis and optimization. A suite of numerical analysis packages were employed including FS2000, Orcaflex and ABAQUS. The pipe resistance envelope during pipelay was developed using DNV limit state criteria. This pipe resistance envelope was used to derive an upper limit to sag bend bending moments for the local ILT analysis. This paper presents details of the methodology, discussions and conclusions for the engineering challenge described above.
Dry Tree Top Tensioned Riser Systems
Authors: Dunn Greg 
Published: June 2014

Abstract
As oil production moves further offshore and into deeper water, the technology needed to meet the increased demands evolves. New technologies and new applications of existing technologies bring new challenges and often create unintended consequences. For floating production vessels, the riser system is critical to the safety of personnel and protection of the environment. However, there is no universal riser package suitable for every project. The riser system must be designed not only for the environmental loads, but also the specific and unique demands of the vessel.
Project engineers responsible for selecting the best solution for developing a field must maintain a holistic view. The decision of the type of production vessel should be based not only on leading interfaces such as location and environment, but also consider trailing interfaces such as the hardware used on the vessel.
This paper outlines the impact that production vessel type has on top tension riser (TTR) systems. Tension leg platforms (TLPs), spars, and semi-submersibles are considered. Design requirements, functions, interfaces, and standard componetry of TTRs are identified. Case studies of riser packages for various vessel types are presented for illustration. Effects on cost, complexity, installation, and ancillary equipment are documented. Future projections and trends are included.

Introduction
Brazil is a major and growing market for offshore oilfield development. As of August 2012, more floating production projects were planned in Brazil than any other country. With that growth comes an expansion of technology and a diversity of solutions to meet the evolving needs of the marketplace. Upon its planned completion, Papa Terra will be the first dry tree offshore development in Brazil. Given the advantages of dry tree systems in the flexibility for drilling, completion, and workover, many more can be expected in the coming years.
Due to the lack of prior dry tree projects in Brazil, many engineers, project managers, and other decision-makers lack exposure to and experience with these systems. This paper provides general information about floating production systems and their corresponding top tension riser systems. Other components and riser types, such as pipelines and steel catenary risers, are not addressed.
Subsea High Boost Multiphase Pump System Development and Applications
Authors: Cerqueira Maxwell , Kuchpil C. Jose de Castro , Silva Luiz Carlos Tosta , Souza Carlos Eduardo Maia  de , Carbone Leonardo , Huguenin Rafael 
Published: June 2014

Abstract
The paper discusses the development of the Subsea High Boost Multiphase Pump System, which led to the first installation of this technology in the Barracuda field, Campos Basin, offshore Brazil. The Helico-axial High Boost Multiphase pump qualification program was started in 2007 (ref. 6), and went through extensive testing and qualification activities, with the latest endurance test being performed in 2011. The Barracuda subsea multiphase boosting system is installed at a water depth of 1040 m with a tie-back distance of 10.5 km to the P-48 platform and was started up in July 2012. The Barracuda multiphase pump is capable of providing high differential pressure in a wide range of gas volume fractions. The high boost multiphase pump is currently being considered to several other applications worldwide as we move towards deeper waters and longer tie-backs. Some more work is being done so this technology could reach the next step, being qualified to a broader range of applications in order to meet the industry needs. The paper will also discuss current and future applications of this technology, and present the latest status of the Barracuda project.

Introduction
Subsea multiphase boosting is an important technology to the oil and gas industry. Many companies have invested a lot of effort, recourses and time in research and developments over the years seeking to develop reliable and robust solutions for the subsea environment. With more than 18 years since the first field application at the Draugen (Shell) field the helico-axial impellers are currently one of the most important and robust technologies for subsea multiphase pumping.
The initial idea for subsea boosting was to extend satellite production from 10 to 50 km away from existing infrastructure. This would make some field developments feasible as it would allow the same production unit to be used for remote well tie-backs. Another clear benefit of this technology is the possibility to increase the oil recovery and accelerate the production without interfering with the wells or the fluid characteristics.
With the growing subsea activities over the past years the operators faced challenges that required equipment which could be able to add higher differential pressure to the multiphase flow. Without modifying the field proven helicon-axial design the multiphase pump was further developed to be able to handle the required differential pressures.
In 2007 the High Boost pump prototype was designed and built in Norway being first tested in February 2008. After conducting tests over more than 2 years the High Boost technology was qualified. In 2012 the first High Boost pump was started up in the Barracuda field (PETROBRAS - Campos Basin) which has been in continuous operation for more than one year so far.