Investigation on the deflagration inhibition effects of potassium salt-modified dry water on CH4/air mixture

Abstract

In this study, three potassium salts were selected to modify dry water powders to assess their effectiveness in mitigating methane explosions. The physical properties of the potassium salt-modified dry water were analyzed, and their impact on suppressing methane explosions was experimentally examined, including key explosion parameters of the premixed methane/air mixtures. Furthermore, kinetic analysis was conducted to reveal the explosion inhibition mechanism of typical potassium salt-modified dry water. The results demonstrate that the potassium salts enhance the inhibition effects of ordinary dry water. Potassium salt-modified dry water significantly extended both the peak pressure time and the maximum pressure rise rate. When φ = 0.8 and φ = 1.0, the peak methane overpressure time was prolonged by 6.6 times and 6.4 times, respectively, compared to ordinary dry water with the same amount of additive. The effects of explosive inhibitors on the adiabatic flame temperature of methane at different stoichiometric ratios were found to follow the order: 0.8 > 1.2 > 1.0. In addition to physical inhibition, the reduction in the concentrations of O, H, and OH radicals due to the addition of explosion inhibitors is a key factor in suppressing methane combustion. The outcomes of this study contribute to improving the performance of gas explosion inhibitors.