Hazards for syngas fires and explosions

Fire and explosion hazards in ammonia plants include releases of flammable materials. The distinction between fire and explosion scenarios is often whether the fuel ignites promptly upon release or has delayed ignition. Prompt ignition prevents formation of a flammable vapor cloud and, thereby, averts a VCE. Syngas contains a significant amount of hydrogen, a fuel that is easily ignited. Industry experience with accidental releases of syngas has been that it promptly ignites. Literature was reviewed for test and accident data for syngas and hydrogen to estimate the probability of prompt versus delayed ignition. No instances of syngas VCEs were found in literature; however, numerous test and accidents were reported for hydrogen. The probability of delayed ignition varied with the release conditions. A conservative estimate of the probability of delayed ignition was developed. © 2010 American Institute of Chemical Engineers Process Saf Prog, 2010