In order to meet the growing demands for energy, plans are currently being made to construct several new liquefied natural gas (LNG) off-load terminals in North America. While LNG provides a relatively clean source of fuel, increased shipment means increased potential for accidental releases. Governmental agencies have recognized the safety concerns about such a possible spill event and have recommended the proactive and preemptive addressing of such concerns.
Several recent studies have examined the likely thermal and other hazards from an LNG vessel accident. One possible threat from such an incident is a pool fire, which could be quite large since the volume of a single tank on an LNG vessel can contain as much as 25,000 m of liquefied gas. In general, there is agreement in the literature on the pool fire geometry, burn regression rate, and thermal emissive power of the fire but less concurrence on possible tank leak rate or surface spread rate on water.
The authors review the existing approaches to this latter phenomenon for unconfined spills. Comparison of model predictions with limited experimental data is also discussed
For low wave conditions, two methods, one by Fay and the other by Weber, have been the most widely used in past models, sometimes with modifications that are discussed in the paper. Similarly, two alternative algorithms have recently been suggested for high wave conditions. The authors review the merits of these two approaches, the expected consequences from each approach, and finally compare them to widely used oil spill spreading formulas under energetic wave conditions.
Author notes
1 The views expressed in this paper are those of the authors and do not necessarily reflect the views of any agency of the Canadian or United States governments.