Experimental research on combustible gas/air explosion inhibition by dry water

The carbon reduction policy to address environmental change has increased the storage, transportation, and use of clean energy represented by hydrogen (H 2 ) and natural gas (mainly composed of methane, CH 4 ). However, its risk of ignition and explosion also brought significant safety risks. Although many previous studies have studied the effect of traditional detonation inhibitors, the inhibition effect of composite explosion inhibition materials still needs further research, especially for H 2 explosion inhibition. In this paper, the effect of dry water (DW), a new type of core-shell structure material, in inhibiting the explosion of combustible gases (mainly H 2 and CH 4 ) has been experimentally studied using a typical 20L spherical apparatus. The results shows that DW can significantly reduce the characteristic parameters during the ignition and explosion process of H 2 and CH 4 . However, its ignition and explosion inhibition effect is related to the type of combustible gas. The maximum explosion pressure of CH 4 is significantly reduced, but the maximum pressure reduction rate of H 2 is more significantly reduced. Compared with typical dry powder inhibitors, the effect of DW inhibition in characteristic parameters during the H 2 ignition and explosion is related to concentration. Moreover, the inhibition effect of DW at higher concentrations is significantly better than BC and ABC dry powders at the same concentration. The inhibition mechanism of DW on the ignition and explosion of combustible gases results from a comprehensive synergy of cooling, dilution, homogeneous radical catalytic inhibition, and heterogeneous radical annihilation. The research conclusions can provide a data basis and theoretical guidance for developing explosion inhibition technology and preventing and controlling H 2 explosions.