Explosion properties of iron dust in pure oxygen at elevated pressure
Résumé
A 50 L explosion vessel was purposely designed and manufactured to investigate the explosion
properties of iron dust in oxygen at elevated pressure. Pressurized oxygen was injected into the vessel
through a perforated tube to blow the iron dust deposited at the bottom of the vessel. This technique
has been calibrated to create a homogenous and turbulent flammable dust cloud. The flammable cloud
was ignited with a pyrotechnic match delivering 60 J. During the first series of tests, the influence of
the initial O2 pressure and mass of iron were investigated. As expected, the maximum pressure and
maximum rate of pressure rise increase when the initial pressure or the ratio mass Fe / mass O2
increases. However, when the iron mass increased, a spontaneous ignition occurred at the beginning
of oxygen injection, resulting in a violent jet fire that perforated the 25 mm thick wall of the vessel.
Further investigations are required to explain this observation. The spontaneous ignition could be
caused by friction between the iron particles and the steel walls or by electrostatics. The influence of
ferric oxide Fe2O3 mixed with iron dust was also studied It resulted in rapid combustion with a high
pressure increase quite different from the one caused by a dust explosion.
Domaines
Ingénierie de l'environnementOrigine | Fichiers produits par l'(les) auteur(s) |
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