Combustion behaviors and explosibility of suspended metal hydride TiH2 dust

In the production and storage processes of metal hydride material of TiH2, there are at least three kinds of explosion hazards, for example, TiH2 dust explosion, H(2 )explosion and hybrid H-2/TiH2 dust explosion. In this study, combustion behaviors of TiH2 dust cloud under isobaric and isochoric conditions were studied using a visual dust combustion facility and a standard 20-L spherical explosion vessel bomb, respectively, and Ti dust and hybrid H-2/Ti dust were used as the reference materials. Experimental results showed that at equal dust concentrations, the flame propagation speed S-f, burning velocity S-L, maximum pressure rise P(ex )and maximum rate of pressure rise (dP/dt)(ex) of TiH2 dust were all higher than those of Ti dust, while much smaller than those of hybrid H-2/Ti dust except the maximum pressure rise P-ex. The hydrogen state and content were the primary factors for the combustion differences of dust explosions. The values of explosion index K-st showed that the explosion risks of these samples increased as follows: Ti- < TiH2 (<) hybrid H-2/Ti dust. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.