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

Abstract

The carbon reduction policy to address environmental change has increased the storage, transportation, and use of clean energy represented by hydrogen (H2) and natural gas (mainly composed of methane, CH4). 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 H2 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 H2 and CH4) 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 H2 and CH4. However, its ignition and explosion inhibition effect is related to the type of combustible gas. The maximum explosion pressure of CH4 is significantly reduced, but the maximum pressure reduction rate of H2 is more significantly reduced. Compared with typical dry powder inhibitors, the effect of DW inhibition in characteristic parameters during the H2 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 H2 explosions.