Analysis of the boiling liquid expanding vapor explosion (BLEVE) of a liquefied natural gas road tanker: The Zarzalico accident

Abstract

10The road accident of a tanker transporting liquefied natural gas (LNG) originated a fire and, finally, 11 the BLEVE of the tank. This accident has been analyzed, both from the point of view of the 12 emergency management and the explosion and fireball effects. The accidental sequence is 13 described: fire, LNG release, further safety valves release, flames impingement on vessel 14 unprotected wall, vessel failure mode, explosion and fireball. According to the effects and 15 consequences observed, the thermal radiation and overpressure are estimated; a mathematical 16 model is applied to calculate the probable mass contained in the vessel at the moment of the 17 explosion. The peak overpressure predicted from two models is compared with the values inferred 18 from the accident observed data. The emergency management is commented. 19 20 Keywords: LNG, Fireball, Road transportation, Blast, Thermal radiation. 21 Highlights 22• Road transportation of LNG is increasing, this implying a certain risk 23• The BLEVE of an LNG road tanker -a rather unusual accident-is analyzed 24• The effects of explosion and fireball are estimated from the observed consequences 25• The correct emergency management avoided further damage to people 26 27 1 1

Fire as a primary event of accident domino sequences: The case of BLEVE

“…In the San Juanico accident (Mexico, 1984), the first BLEVEs occurred 70 seconds after the first jet fires appeared; in the accident occurred in Nijmegen (The Netherlands) in 1978, a tanker of LPG exploded at a filling station just 3 minutes after fire started underneath during unloading. However, the time to failure can be significantly higher: in the accident occurred in Zarzalico (Spain, 2011), an LNG road tanker was exposed to a very strong fire during approximately seventy minutes before the explosion occurred [31]. Table 6 gives the time to failure for a series of accidents involving fireBLEVE domino sequences [22].…”

“…Table 7. Water application rates from API 2510A [31]. However, water deluge systems and water monitors have some practical disadvantages, amongst which the large overall water requirement and corrosion/maintenance problems can be cited as the most important ones.…”

The Risk to Structures Built Near Roads and Rails Used for Moving Hazardous Materials

“…Abbassi (2007) and Tauseef et al (2010). Planas-Cuchi et al (2004), Bonilla Martinez et al (2012 and Planas et al (2015) described in detail two BLEVEs of road tankers which occurred in Spain in 2002 and 2011. However, neither of these publications attempted to systematise information on a greater or lesser number of BLEVEs in transportation in terms of, say, types commodities involved in accidents or damage to roadside property.…”

“…In addition, these projectiles are usually small with respect to buildings and most of open-air industrial equipment. Projectiles ejected by a BLEVE of a tanker vessel will be large and relatively deformable vessel fragments, mainly end-caps and oblong end-caps of the vessel (Planas-Cuchi et al 2004;Planas et al 2015). They can be classified as "soft" ones and may collide with the target at different angles of in-cidence and different spatial orientation with respect to the target.…”

Consequence modelling of a truck explosion

“…Process Hazard Analysis Software Tool -Phast developed by Det Norske Veritas -DNV is one of the world's most used software for modelling consequences of potential accidents, from leakage, to diffusion and explosion or toxicity. Computational simulations of fire and explosions and their corresponding results have to be validated with experimental results, but such experimental results are quite difficult to obtain [26][27][28][29]. For analysing the accident scenario presented in this paper, there was used the latest version of Phast, including the 3D explosion component, since the software has been validated with numerous fires and explosions experiments [30][31][32][33].…”