تركـي الوبيري
09-26-2007, 08:43 AM
a gas at atmospheric pressure but is a liquid when pressurized (for example, liquefied petroleum gas). The substance will be stored partly in liquid form, with gaseous vapors above the liquid filling the remainder of the container. If the vessel is ruptured for example, due to corrosion, or failure under pressure the vapors portion may rapidly leak, dropping the pressure inside the container and releasing a wave of overpressure from the point of rupture.
This sudden drop in pressure inside the container causes violent boiling of the liquid, which rapidly liberates large amounts of vapor in the process. The pressure of this vapor can be extremely high, causing a second, much more significant wave of overpressure (i.e., an explosion) which may completely destroy the storage vessel and project fragments over the surrounding area. BLEVEs can also be caused by an external fire nearby the storage vessel causing heating of the contents and pressure build-up. BLEVE does not require a flammable substance to occur, and therefore is not usually considered a type of chemical explosion. However, if the substance involved is flammable, it is likely that the resulting cloud of the substance will ignite after the BLEVE has occurred, forming a fireball and possibly a fuel-air explosion, also termed a vapors cloud explosion (VCE). If the materials are toxic, a large area will be contaminated.
This sudden drop in pressure inside the container causes violent boiling of the liquid, which rapidly liberates large amounts of vapor in the process. The pressure of this vapor can be extremely high, causing a second, much more significant wave of overpressure (i.e., an explosion) which may completely destroy the storage vessel and project fragments over the surrounding area. BLEVEs can also be caused by an external fire nearby the storage vessel causing heating of the contents and pressure build-up. BLEVE does not require a flammable substance to occur, and therefore is not usually considered a type of chemical explosion. However, if the substance involved is flammable, it is likely that the resulting cloud of the substance will ignite after the BLEVE has occurred, forming a fireball and possibly a fuel-air explosion, also termed a vapors cloud explosion (VCE). If the materials are toxic, a large area will be contaminated.