Vapor Cloud Hazards of Enclosed Liquid Flammable Processes

Simple approaches to evaluate vapor cloud explosion hazards from releases within enclosed process plants often assume that the entire volume of the building in filled with flammable vapors.  This can result high loads that could be overly conservative, particularly for flammable liquid releases.  Operations involving solvent processes are often located in such enclosed buildings.  Such processes operate at relatively low temperatures and pressures, but with sufficient quantities of solvent to be PSM covered.  This paper addresses vapor cloud generation and deflagration from the release of two common solvents, hexane and methanol, within enclosed process buildings using CFD simulation tools.  It evaluates the effect of containment curbing on vapor cloud formation and the effect of pressure relief through wall panel failure on deflagration severity.  Comparisons are made between the results of the each approach in an effort to aid companies in applying results to their processes and PSM program.