Abstract: The effects of different qualities of perlite, dopamine-coated perlite, and SiO2 powder on the shape of flame propagation, methane explosion pressure, and flame propagation velocity were investigated by using a self-constructed experimental platform with 9.5% methane as the explosive gas. Thermogravimetric analysis, particle size analysis, XRD analysis and scanning electron microscopy were used to analyze the thermal stability as well as the surface microcosmic condition of perlite powder before and after coating, and to analyze the detonation suppression mechanism of modified perlite by comparison. Through a variety of data comparisons, the three powders have the effect of inhibiting methane explosion, in which the effect of dopamine-coated perlite is the most obvious, spraying 320 mg working conditions of the maximum explosion pressure is the smallest, compared with the percentage of pure methane decreased by 62.3%, the maximum propagation of the flame of the 360 mg is the smallest, a decrease of 42.6%. The addition of dopamine-coated perlite powder hinders flame propagation and interrupts the chain reaction of methane explosion through chemical and physical suppression of methane explosion, thus achieving the effect of methane explosion suppression.

Key words: perlite, dopamine, flame shape, explosion pressure, flame velocity