Synergistic inhibition characteristics and kinetics of hydrogen explosion by two-phase suppressant N2-KHCO3

Abstract

Hydrogen energy has a promising future as a novel energy source in the 21st century. Resource exploitation and utilization of hydrogen energy are considered as crucial methods to achieve the medium and long-term goals of carbon peaking and carbon neutrality. However, hydrogen explosions are extremely destructive and can lead to severe consequences, making the effective suppression of hydrogen explosions a focal point in the field of hydrogen safety technology research. In this paper, the research equipment was a 20 L spherical explosion device used to analyze the hydrogen explosion characteristics under the synergistic effect of N₂-KHCO₃. Based on this, CHEMKIN was utilized to study the kinetic parameters of hydrogen explosion under the influence of suppressants. The results showed that single-phase N₂ suppressed hydrogen explosion. With the increase of N₂ volume fraction, the explosion pressure decreased. Specifically speaking, 30 vol% N₂ reduced the hydrogen explosion pressure by 32.51%. Besides, single-phase KHCO₃ had an inhibitory impact, but it had little effect on the reduction of explosion pressure. In the study of synergistic effect, 25 vol% N₂ and 750 g/m³ KHCO₃ could completely suppress hydrogen explosion, and 30 vol% N₂ combined with 250 g/m³ KHCO₃ could also completely suppress hydrogen explosion. Therefore, the synergistic effect of N₂-KHCO₃ in the experiment remarkably inhibited hydrogen explosion. In the study of kinetic parameters in this paper, N₂-KHCO₃ significantly reduced the formation rate and sensitivity of H and OH, and reduced the explosion temperature sensitivity coefficient. Taken together, the two-phase synergistic effect of N₂-KHCO₃ effectively reduced the sensitivity and intensity of hydrogen explosion and inhibited the chain reaction of hydrogen explosion. This paper provides the theoretical basis for broadening the direction of potassium salt development. Furthermore, it offered technical guidance for the application of gas-solid two-phase explosion suppression technology. The future research direction is to optimize the type and ratio of two-phase explosion suppressants, achieve the reduction purpose and efficiency of explosion suppressants, and enhance their practical application effect.