Basic Principles of BLEVEs

In this section, the phenomenon of BLEVE is discussed according to theories proposed by Reid (1976), Board (1975), and Venart (1990). Reid (1979, 1980) based a theory about the BLEVE mechanism on the phenomenon of superheated liquids. When heat is transferred to a liquid, the temperature of the liquid rises. When the boiling point is reached, the liquid starts to form vapor bubbles at active sites. These active sites occur at interfaces with solids, including vessel walls. 

Boiling in the bulk of the fluid generally takes place at submicron nucleation sites as impurities, crystals, or ions. When there is a shortage of nucleation sites in the bulk of the liquid, its boiling point can be exceeded without boiling then the liquid is superheated. There is, however, a limit at a given pressure above which a liquid cannot be superheated, and when this limit is reached, microscopic vapor bubbles develop spontaneously in the pure liquid (without nucleation sites). 

Opschoor (1974) applied the Van der Waals equation of state to estimate the maximum superheat temperature for atmospheric pressure from the critical temperature (TJ (i.e., that temperature above which a gas cannot be liquefied by pressure alone) as follows  

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