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Integrated and automated integrity management is essential for Arctic and cold region pipeline failure prevention, predictive maintenance, and life extension because the consequence of a failure will be disastrous both environmentally and economically. Without managing integrity, the condition of pipeline would continue to deteriorate until found unfit for service or premature failure. Real-time Condition Monitoring (CM) is a sensor- based monitoring technique aimed at enhancing the productivity of pipeline operation. The main intent of condition monitoring is to assess operating conditions and performance, improve performance, aid maintenance, extend life, and inform operator if the integrity is compromised. Other purpose of monitoring is to provide warning when something is starting to go wrong, and provide instantaneous information when things have gone wrong. This paper presents a recently developed concept and methodology for Arctic pipeline integrity management using Inspection, Maintenance and Repair (IMR) strategy using real-time CM data by probabilistic risk assessment. The probabilistic risk assessment is performed by combining advanced probabilistic analysis with computation. In this paper, the joint probability of failure arising from potential pipeline defects (e.g. corrosion, cracking, and strain) and likely operational deviations (e.g. pressure, temperature, and vibration) is computed real-time using the CM data to predict a condition-based IMR strategy. Having such a model would enable rapid decision-making regarding pipeline failure prevention, predictive maintenance and life extension.
In this paper I present full wave field simulation results in an acoustic-viscoelastic domain and show how flexural waves interact with the surrounding air and water instead of only focusing on the flexural wave. This paper is devoted to the advantages of full wave field simulations employing viscoelastic models compared to purely elastic models. Viscoelastic simulation provides results that better resemble measured field data than equivalent elastic or 1D flexural wave simulations are capable of. Elastic full wave field simulations suffer from undesired dispersive modes and oscillations obscuring the true interaction of different wave types. Application of acoustic-viscoelastic full wave field simulation can help to test and improve planned survey geometries and the processing workflow.
Turret-Moored FPSOs are frequently used for deepwater developments worldwide, with consideration of disconnectable turrets for harsh environment applications. This trend makes the interaction between the FPSO hull, mooring system, and riser systems a vital design parameter for arctic conditions.
This paper provides a review of the various riser systems that can be considered for turret-moored FPSOs. These include proven coupled and decoupled systems (flexibles, Steel Catenary Risers, Steel Lazy Wave Risers, and hybrid decoupled riser systems), and also new riser concepts (e.g. the TCR - Tethered Catenary Riser, or the TSLWR - Tethered Steel Lazy Wave Riser). These systems are described in terms of design and functionality.
These riser systems are discussed with consideration of the particular challenges of disconnectable turret-moored FPSOs and specificities of arctic conditions.
Physical ice management is a critical element of station keeping operations in waters characterized by drifting sea ice: it minimizes ice related downtime. Ice management represents also an important cost driver for Arctic offshore developments. The ice management fleet needs to be assembled considering the particular site, season of interest and corresponding expected environmental conditions, the particular facility capabilities to operate in ice covered waters, and the desired operability of the entire system.
The paper describes the physical ice management trials performed during the Offshore Newfoundland Research Expedition in April 2015. These trials were planned and executed with the purpose to generate data to support the development of numerical models for simulating key aspects of the ice management operation.
The results of this paper are applicable to ice management fleet design. Particular focus is on Arctic and sub-Arctic areas characterized predominantly by open water, but still containing the risk of sea ice invasions, and vessels expected to operate in such areas.
Results from the field trials are presented and discussed. The paper elaborates on the schemes for numerical modeling of ice management, the challenges, and how field trial data can support the development of effective simulation tools.
Description of the Paper: Our paper outlines the history of spill response requirements in the U.S. Arctic and how incidents have shaped spill legislation. A review of the equipment utilized in spill response from the 1980’s and focuses on the exploration efforts in the Beaufort and Chukchi Seas. It also covers a review of the changing spill response requirements and their impact on the Shell exploration effort.
The experiments and real life experience with spills in ice are reviewed and the equipment and tactics developed from this experience will be described. The limitations of each recovery option are explored and when each tactic would be effective in a spill event.
Proposed spill response platforms for effective spill response operations are identified and how spill response equipment can be deployed in the field.
Application: Spill response options are shown for working in the Arctic in the various ice conditions that may be experienced throughout the year.
Results, Observations and Conclusions: The paper covers the changes in response equipment designed to operate in the Arctic and the tactics that are effective as well as touch on future research that is needed to improve recovery options.
Significance of Subject Matter: The effectiveness of a spill mitigation plan is critical in securing the permits and social license to explore for hydrocarbons in the fragile Arctic environment.
The Arctic regions offer significant resource bases for energy supplies for the future. The Arctic developments has been challenged during the last years due to relatively high risk and cost levels related to the remote locations, harsh environment and environmental risks. The price of energy has fallen significantly and Liquefied Natural Gas (LNG) prices has followed the oil market, therefor the development of LNG facilities in the Arctic has to offer substancial cost benefits over what was planned some few years back.
Gas fields in the Arctic can be developed with LNG plants onshore, Floating LNG (FLNG) or by Gravity Based Structure (GBS) LNG solutions. Onshore developments has been the only alternative developed to date but logistical, foundation and lower productivity for construction, hook up and commissioning in arctic conditions has enabled another development concept to be evaluated. FLNG in shallow water and ice infested areas has not yet been considered a feasible development solution.
The GBS LNG concept offers solutions to many of the challenges in developing a large scale LNG plant in the arctic. The self contained GBS LNG based on compact design with integrated topside, Product storage and offloading in one unit can improve the execution of: Construction and integration in a yard instead of in an remote localization with harsh environment large parts of the year Reduced logistical challenges and no ice breaking tansport vessels required Locating the GBS LNG in permafrost free site Concrete GBS can be constructed locally to ensure substantial local content Securing the project schedule by working in a controlled environment with established infrastructure and work force Significant reduction in bulk quantities due to compact design Integrated ice barrier and potentially ice management systems in the GBS
Construction and integration in a yard instead of in an remote localization with harsh environment large parts of the year
Reduced logistical challenges and no ice breaking tansport vessels required
Locating the GBS LNG in permafrost free site
Concrete GBS can be constructed locally to ensure substantial local content
Securing the project schedule by working in a controlled environment with established infrastructure and work force
Significant reduction in bulk quantities due to compact design
Integrated ice barrier and potentially ice management systems in the GBS
The GBS LNG concept has been developed to be a flexible solution where; Train size and number of trains can be accommodated - up to 10 MTPA LNG capacity per GBS Large flexibility in LNG and condensate storage capacity Water depth ranging from 13-30m Design one build many - easy hook up for multiple LNG GBSs Cooling medium (Air or Water cooled) Driver selection - GT or Electrical drive Self contained with Living Quarter, Flare and utilities in produced on board Flare can be installed on GB S
Train size and number of trains can be accommodated - up to 10 MTPA LNG capacity per GBS
Large flexibility in LNG and condensate storage capacity
Water depth ranging from 13-30m
Design one build many - easy hook up for multiple LNG GBSs
Cooling medium (Air or Water cooled)
Driver selection - GT or Electrical drive
Self contained with Living Quarter, Flare and utilities in produced on board
Flare can be installed on GB S
This paper is based on several conceptual and pre-FEED studies for the arctic and sub arctic environment where the GBS LNG solution has been evaluated favourable over the onshore development alternative, especially in location with ice infested waters and were permafrost on land is present.
In certain offshore shallow water production areas in cold regions the sea conditions are characterized by first year and potentially multi-year ice features. Unlike some other arctic regions, which are characterized by icebergs, there are regions where no icebergs occur. However, gouges are formed by rafted ice, pressure ridges, and multi-year ice from the polar pack that forms deep keels. Ice gouging of the seabed in these areas is caused by winds, currents and waves driving the ice sheet containing these ice keels.
As more reserves are being found in shallow water arctic and sub-arctic environments, there is a need to determine how best to develop these resources cost effectively. See
This paper discusses a novel design to best protect the subsea template and its mechanical equipment. Furthermore, this paper outlines the process undertaken for designing a subsea drilling and production template and protective structure by encasing the template within a protective structure that is placed in an armored excavation, or "Glory Hole", to prevent sand intrusion and ice keel penetration.
To protect a drilling and production template in shallow water, an enclosed structure was required to be embedded in the soil at the bottom of a Glory Hole with a full-time domed protection cover to protect from ice and soil entrance. Slotted doors allow jackup access to the template during drilling. Operation of the Wellheads contained within the Subsea Template is remotely controlled by a subsea cable containing electrical, hydraulic and fiber optic cables and tubes. The operation of the facilities can be monitored and controlled at the Command and Control Center located onshore and connected to the offshore template by the control cable.
A floating platform in deep water Eastern Canada is required to withstand iceberg loads and/or be disconnected and towed away only in the event of very large approaching icebergs, leaving the mooring lines and risers in-place, support large topsides and provide large quantities of oil storage in the hull. Additionally, the platform should provide low motion response to storm and ice loads to maximize the operational uptime and facilitate the use of a large number of different riser systems including steel catenary risers (SCR).
This paper presents the details of a Disconnectable Concrete Spar FPSO platform that has been configured to satisfy all the above requirements and is able to be constructed locally in Eastern Canada. The paper describes a number of key features of the Spar shaped hull, mooring and riser systems that are specifically designed to withstand large iceberg loads and other environment loads while maintaining the characteristic low motion response to storm environments. The design helps to minimize disconnection frequency due to approaching icebergs and disconnection may only be required for very large icebergs or ice islands. Additionally, the system has been designed to minimize disconnection and reconnection time.
Thaw subsidence can damage the infrastructure including buildings, roads and airfields founded on ice- rich permafrost, increase their maintenance costs, change the landscape and influence the sustainable development in the northern region. Information about the ground movements is important for making decisions on various geotechnical approaches to reduce impacts of permafrost degradation. However, field measurements of ground movements and long term monitoring using traditional field survey may be logistically expensive in vast and remote Northern Canada and Alaska, USA. The ability to measure surface displacements, identify the areas being impacted, and provide information of seasonal timing using remote sensing techniques would improve the knowledge and expertise of those involved in infrastructure engineering and management where permafrost is degrading. Traditional Interferometric Synthetic Aperture Radar (InSAR) measurements of deformation do not consider the effects of seasonal freeze-thaw, thus may not effectively reveal the long term trend of ground movements in permafrost region. In this paper we propose to quantitatively evaluate the seasonal ground movements resulted from on-going seasonal freezing and thawing, and estimate long term deformation of linear infrastructure in permafrost area using InSAR technique. The proposed approach has been tested on Alaska Highway built on permafrost at Beaver Creek, Yukon, Canada using Radarsat 2 data acquired during 2013-2015. Results indicate that there was long term deformation at a rate of five cm/year, in addition to an average of magnitude of vertical movement of 4 cm between winter heaving and summer thawing during annual climate cycles.
A communications company is installing a subsea fiber optics cable from Europe to Asia around North America through the Beaufort and Bering Seas. At various points along the main line branching units are installed to allow for branch legs to be laid to various villages along the coastline of Alaska. These branch legs will provide vital telecommunication service to remote communities and businesses. The villages include Nome, Kotzebue, Point Hope, Wainwright, Barrow and Oliktok Point (Purdhoe Bay). See