Suppression effect of nanocomposite inhibitor on Methane-Coal dust explosion flame propagation

Abstract

To enrich the methane–coal dust explosion inhibition theory at different methane concentrations, the influence of the potassium oxalate-montmorillonite (OA-Mt) nanocomposite inhibitor on the flame propagation characteristics of 5%, 7% and 9% methane–coal dust explosion was studied experimentally and its explosion inhibition mechanism was revealed. Results showed that the optimum K2C2O4 loading concentration for explosion flame inhibition was 80%. The flame brightness was weakened, the flame instantaneous peak velocity vm was decreased, and the flame average velocity inhibition ratio φ was enhanced, proving that OA-Mt could be adopted as an excellent inhibitor for the methane–coal dust explosion. Additionally, OA-Mt had the most significant inhibition on 7% methane–coal explosion. Finally, an inhibition physical model of OA-Mt on methane–coal dust flame zones was established and the suppression mechanism was discussed. The physical-dominated inhibition effect in the flame preheating zone and the chemical-dominated inhibition effect in the combustion reaction zone co-mitigated the methane–coal flame propagation.