Fires
BLEVEs can be caused by an external fire near the storage vessel causing heating of the contents and pressure build-up. While tanks are often designed to withstand great pressure, constant heating can cause the metal to weaken and eventually fail. If the tank is being heated in an area where there is no liquid, it may rupture faster without the liquid to absorb the heat. Gas containers are usually equipped with relief valves that vent off excess pressure, but the tank can still fail if the pressure is not released at the correct rate. Relief valves are sized to release pressure fast enough to prevent the pressure from increasing beyond the strength of the vessel, but not so fast as to be the cause of an explosion. An appropriately sized relief valve will allow the liquid inside to boil slowly, maintaining a constant pressure in the vessel until all the liquid has boiled and the vessel empties.
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 vapor cloud explosion (VCE). If the materials are toxic, a large area will be contaminated.
Read more about this topic: Boiling Liquid Expanding Vapor Explosion
Famous quotes containing the word fires:
“It is an evil world. The fires of hatred and violence burn fiercely. Evil is powerful, the devil covers a darkened earth with his black wings. And soon the end of the world is expected. But mankind does not repent, the church struggles, and the preachers and poets warn and lament in vain.”
—Johan Huizinga (1872–1945)
“Talleyrand said that two things are essential in life: to give good dinners and to keep on fair terms with women. As the years pass and fires cool, it can become unimportant to stay always on fair terms either with women or one’s fellows, but a wide and sensitive appreciation of fine flavours can still abide with us, to warm our hearts.”
—M.F.K. Fisher (b. 1908)
“When the villagers were lighting their fires beyond the horizon, I too gave notice to the various wild inhabitants of Walden vale, by a smoky streamer from my chimney, that I was awake.”
—Henry David Thoreau (1817–1862)