Abstract: Uses the CHEMKIN software to establish a kinetic model of the chemical reaction of the explosion of methane/ethylene/hydrogen multiple combustible gases suppressed by phosphorus-nitrogen series explosion suppressants, including ammonium dihydrogen phosphate (ABC) and melamine cyanurate (MCA), and conducts numerical simulation calculations. The model includes the kinetics model of the chemical reaction of multiple combustible gas combustion and the kinetics model of the thermal decomposition of phosphorus-nitrogen series explosion suppressants, with a total of 61 components and 259 elementary reactions. According to the simulation calculation, the mole fraction changes of each key component of the multiple combustible gas, the temperature changes at the reaction equilibrium, the mole fraction changes of hydrogen free radicals and hydroxyl free radicals, and the changes of temperature sensitivity coefficients were obtained to explore the key explosion suppression components and analyze their reaction pathways. This reveals the explosion suppression mechanism of the explosion suppressant. The results show that both ABC and MCA have good explosion suppression effects on multiple combustible gases, and the explosion suppression effect increases with the increase of ABC and MCA proportions, and the explosion suppression effect of ABC is better than MCA. Both explosion suppressants can achieve explosion suppression by promoting the combination of H radicals and OH radicals to form more stable H2O. The main explosion suppression mechanism of ABC is the formation of the HOPO and PO2 forming 2HOPO?PO2 suppression cycle, consuming a large amount of H radicals and OH radicals to produce more stable H2O, and cutting off chain reactions to suppress explosions. The main explosion suppression mechanism of MCA is that HNCO consumes H radicals and OH radicals to produce H2O and cut off chain reactions to suppress explosions.

Key words: coal spontaneous combustion, multiple combustible gas explosion, phosphorus-nitrogen series explosion suppressant