Potential Mitigations for LNG Pool Fires

After its beginnings over 50 years ago in international import/export and peak-shaving applications, the use of liquefied natural gas (LNG) continues to expand into new applications. In recent years, many of these applications have involved the use of LNG as a vehicular fuel, creating the necessity of small and medium-sized facilities to serve these needs. While the LNG industry has for decades been concerned about the potential hazardous impacts of accidental releases, the limited real estate for smaller facilities has made siting of such facilities more difficult. Because LNG regulations require that the effects of accidental releases on offsite areas be controlled or minimized, LNG facilities often include an impoundment basin that limits the size of a vapor cloud or a pool fire. Even with a well-designed impoundment, a pool fire involving LNG is a potentially damaging event due to the burning properties of LNG. An impoundment fire is one of the more straightforward hazards to model – until mitigation measures are considered. In this analysis, several potential choices for pool fire mitigation are evaluated. The associated modeling methodologies are outlined, and the effects of the mitigations are presented. Considerations of cost, active versus passive mitigations, and potential reduction on thermal radiation impacts, both onsite and offsite, are discussed.