Abstract
Gas explosions are destructive disasters in coal mines. Coal mine gas is a multi-component gas mixture, with methane (CH₄) being the dominant constituent. Understanding the process and mechanism of mine gas explosions is of critical importance to the safety of mining operations. In this work, three flammable gases (CO, C₂H₆, and H₂) which are commonly present in coal mines were selected to explore how they affect a methane explosion. The explosion characteristics of the flammable gases were investigated in a 20 L spherical closed vessel. Experiments on binary- (CH₄/CO, CH₄/C₂H₆, and CH₄/H₂) and multicomponent (CH₄/CO/C₂H₆/H₂) mixtures indicated that the explosion of such mixtures is more dangerous and destructive than that of methane alone in air, as measured by the explosion pressure. Furthermore, a self-promoting microcirculation reaction network is proposed to help analyze the chemical reactions involved in the multicomponent (CH₄/CO/C₂H₆/H₂) gas explosion. This work will contribute to a better understanding of the explosion mechanism of gas mixtures in coal mines and provide a useful reference for determining the safety limits in practice.