Hybrid H2/Ti dust explosion hazards during the production of metal hydride TiH2 in a closed vessel

Abstract

The explosibility of hybrid H2/Ti dust in the production of metal hydride TiH2 was simulated and studied using a 20-L spherical vessel. The influential factors for the explosion performance of hybrid H2/Ti dust, including particle size distribution and polydispersity, humidity, temperature, hydrogen content, inert gas and degree of reaction, on hybrid explosion were investigated. Results showed that both the mean particle sizes and particle size polydispersity had significant effects on the dust severity of hybrid H2/Ti dust. The explosion severity of hybrid H2/Ti dust was enhanced at a higher temperature in a certain range, and it presented a trend of increasing at the early stage and then decreased both for the increasing humidity and hydrogen pressure. Explosion inhibition effects of typical inert gases for hybrid H2/Ti dust increased in the following order: argon < helium < nitrogen. The values of (dP/dt)ex and Vf decreased along with the reaction process, while the value of Pex kept stable, which showed that the hydrogen state had no obvious impact on Pex but significantly affected the explosion risk of hybrid H2/Ti dust, and special attention should be paid to the initial stages of the production process of TiH2.