Experimental Research on the Suppression Effect of Different Types of Inert Dust on Micron-Sized Lignite Dust Explosion Pressure in a Confined Space

Coal is an important strategic resource in the world; coal production safety has always been widely concerned. In coal mine production, inert dust can effectively reduce coal dust explosion accidents in mine tunnels. To reveal the suppression effect of inert dust on lignite dust explosion, CaCO3, SiO2, and NH4H2PO4 are selected for suppression experiments. It is found that the lignite dust explosion pressure decreases continuously as the mass percentages of inert dust mixed into lignite dust increase. By calculating the molar mass, the suppression effects of CaCO3 and SiO2 on lignite dust explosion are compared. The lignite dust no longer explodes when the mass percentage of NH4H2PO4 dust mixed into lignite dust is 70%, indicating that NH4H2PO4 is more effective than that of CaCO3 and SiO2. The smaller the particle size of NH4H2PO4, the better the suppression effect on explosion. The lignite dust does not explode when the mass percentage of NH4H2PO4 is 60% and the particle size of NH4H2PO4 is 25-38 mu m, which proves that decreasing the particle size of NH4H2PO4 is important to suppress explosion. The research results are of great significance for grasping the explosion suppression effect of inert dust on lignite dust.