02/10/2020 | Return to Latest News
A decision support system for iceberg management and more
Icebergs present a significant design challenge for oil and gas operations offshore Newfoundland and Labrador. They pose risks to structures above the ocean surface (such as production platforms or moored offshore drilling units), as well as subsea infrastructure (such as pipelines and wellheads). Iceberg management (towing, in particular) significantly reduces the risk of iceberg interaction with offshore structures.
Improving iceberg towing success can increase safety for those working offshore and enables optimized facilities design, with potential reductions in design loads and thus capital costs of new offshore facilities. Moreover, it also results in improved vessel utilization and potential reductions in emissions as well as operating costs.
On the Grand Banks, iceberg management is currently carried out with knowledge only of the above-water shape. C-CORE has developed a decision support tool, SIMS (the Smart Iceberg Management System), to rapidly generate 3D iceberg shape profiles and integrate them with tools to improve iceberg management success and efficiency.
The SIMS Rapid Iceberg Profiling system utilizes a hull-mounted LiDAR to profile the above-water portion of the iceberg (sail) and a multibeam sonar to profile the below-water portion (keel). In just 15-30 minutes, a vessel equipped with the profiling system can circumnavigate an iceberg twice, collecting the data required to generate a 3D image of the shape. Because icebergs are in motion while being profiled, C-CORE has developed software that automatically corrects the collected data for iceberg drift and rotation and removes “noise” to generate the 3D iceberg shape. A user-friendly interface enables trained vessel crew (rather than specialists) to operate the system after the initial installation and setup has been completed.
After system trials at sea in 2018 and 2019 on an anchor handling supply tug and a 30m fishing vessel, the database of available high-quality 3D iceberg profiles increased to 200. This significantly improved our understanding of iceberg shape relationships and their implications for the design of new structures offshore Newfoundland and Labrador.
Decision Support Tools
Iceberg Stability and Net Fit Tools
Icebergs can be towed by either single ropes or nets. Some 38% of iceberg tow attempts result in rope/net slippage and 10% in iceberg rolling. Both rope/net slippage and iceberg rolling events result in hours of downtime to retrieve and re-deploy the rope/net. The Iceberg Stability Tool uses the profiled 3D iceberg shape and identifies the the most stable tow directions and reduce the frequency of iceberg rolling. The Net Fit Tool provides a visual comparison of the shapes of both iceberg and net, helping to identify areas that should be avoided to decrease the likelihood of slippage. Both tools can be used by towing vessel operators to allow for more informed decision making regarding the direction to try to tow icebergs.
Iceberg Impact Load Assessment Tool
The threat from approaching icebergs must be assessed quickly and accurately to determine the appropriate response. The Iceberg Impact Load Assessment Tool uses the actual profiled iceberg shape along with measured environmental conditions to estimate the potential iceberg impact forces. This tool can help operators determine the threat that a specific iceberg poses to a given platform. In a scenario with multiple icebergs in the vicinity of the platform, the tool may enable operators to prioritize management of the most threatening icebergs.
Iceberg Drift Forecast Tool
Iceberg drift forecasting is important for ice management decisions; by using iceberg profiles measured in real time, C-CORE improved drift forecasting by 20%. This can help to improve ice management in terms of allocating ice management vessels, prioritizing tow targets when multiple icebergs are present, and informing decisions about shutdown, all of which can help reduce downtime, emissions and costs.
The complex geometry of icebergs, paired with the harsh environment presents significant challenges for data and data processing. C-CORE is working to continually improve the data quality, processing speed and cleaning algorithms of the SIMS rapid iceberg profiling system, as well as the capabilities of the tools to enable more informed decision-making during iceberg management activities.
For a more detailed account of C-CORE’s Smart Iceberg Management System, read the October 2020 issue of the Journal of Ocean Technology, here.