This paper investigates the inhibitory effects and mechanisms of different powder inhibitors on corn starch explosion flame propagation. The results indicate that ABC powder exhibits the strongest suppression effect, followed… Click to show full abstract
This paper investigates the inhibitory effects and mechanisms of different powder inhibitors on corn starch explosion flame propagation. The results indicate that ABC powder exhibits the strongest suppression effect, followed by Al(OH)3 powder and dolomite powder. Increasing the inerting ratio progressively suppresses the flame acceleration characteristics of corn starch explosion. The addition of 25 wt.% ABC powder significantly inhibits flame propagation, reducing the average flame propagation velocity by 83.6% and the maximum propagation velocity by 91.7% compared to the uninhibited condition. Compared to Al(OH)3 and dolomite powder, ABC powder has a lower initial thermal decomposition temperature, a broader pyrolysis temperature range, and greater endothermic efficiency. The thermophysical properties of the powder inhibitors show good consistency with their explosion suppression effectiveness. The inhibitors generate NH3, H2O, SO2, and N2, which effectively reduce both the laminar burning velocity and heat release rate of corn starch pyrolysis gases. The competition between H + O2 = O + OH and H + CH3(+M) = CH4(+M) dominates the combustion reactions of pyrolytic gases from corn starch. The CO2, H2O, and NH3 generated by the thermal decomposition of inhibitors do not alter the fundamental reactions governing combustion. However, the generated SO2 introduces two additional key inhibitory elementary reactions: H + SO2(+M) = HOSO(+M) and H + O2(+M) = HO2(+M).
               
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