The hazardous release of cryogenic fluids, such as LNG, can pose a threat to both staff and assets on floating LNG installations. In response to this issue, Lloyd’s Register Energy has created a guidance note, which provides a consistent method for establishing cryogenic exposure.
The Vice President Technology in Lloyd’s Register Energy Consultation team, Joar Dalheim, stated: “As natural gas is becoming increasingly important to satisfy global energy demands, so is the need for safer and more efficient facilities. Given the large quantities of cryogenic materials present on a floating LNG facility, there is a serious risk of extensive damage in the event of cryogenic failure of critical components. As the estimation methods currently available are granular, we see a need for a more inclusive approach. This is what we are delivering with our guidance note”.
The guide provides two differing methods for such a scenario. The first is the Initial Cryogenic Risk Analysis (ICRA), which is particularly useful in the early design stages, because it uses 2D models to estimate where the hazardous zones are. However, it cannot provide more detailed analysis, which might be required because of certain walls, platforms, etc. The Advanced Cryogenic Risk Analysis (ACRA) method, on the other hand, is based on 3D computational fluid dynamics (CFD) models, and, therefore, can incorporate detailed specifics in the risk assessments.
On discussing this difference, Dalheim claimed: “Integrating 3D analytical tools in the cryogenic risk analysis removes many of the uncertainties and limitations involved when relying on 2D analyses alone. This increases the accuracy of the hazard predictions and eliminates the need for arbitrary assumptions”.
The guidance on cryogenic spills is the latest offering in Lloyd’s Register Energy’s suite of guidance notes on risk-based methodologies. These risk-based analysis guidance notes provide risk-based methodologies to establish explosion, collisions, fire and cryogenic loads based on a probabilistic approach, rather than a worst-case scenario with the objective of minimising risk, improving safety, quality and performance.
Edited from press release by David Rowlands
Read the article online at: https://www.lngindustry.com/floating-lng/10092015/safeguarding-against-hazards-on-lng-installations-1268/