A modeling approach to assess the effectiveness of BLEVE prevention measures

Distribution and storage of liquefied pressurised gases is a critical safety issue, often resulting in a very high individual and societal risk, at least in densely populated zones. Several risk assessments pointed out that this is mostly due to the possible occurrence of a Boiling Liquid Expanding Vapour Explosions (BLEVE) of the tank, that may be exposed to an intense fire as a consequence of release scenarios. In the present work, a modelling approach is presented for the calculation of fired BLEVE probability. Simplified models were obtained for the estimation of the vessel time to failure with respect to the radiation intensity on the vessel shell. The time to failure was compared to a reference time required for effective mitigation actions and thus related to the escalation probability. The analysis of the effect of protective measures, such thermal insulating coating and pressure relief devices, on the time to failure allowed the identification of the necessary requirements for effective BLEVE prevention.