Inhibition of Aluminum Powder Explosion by a NaHCO3/Kaolin Composite Powder Suppressant

ABSTRACT

In this paper, NaHCO₃/kaolin composite powder explosion suppressor was prepared by antisolvent-dissolution method. The effect of NaHCO₃/kaolin composite powder explosion suppressor on aluminum powder explosion was studied by Hartmann tube and 20 L spherical explosion tank. The propagation suppression experiment shows that as the content of the NaHCO₃/kaolin composite powder inhibitor increases, the explosion flame propagation length and speed gradually decrease. When 50% (by mass) NaHCO₃/kaolin composite powder inhibitor is added, the flame propagation of aluminum powder is suppressed. The experiment of suppressing the explosion of aluminum powder with a composite powder suppressant was carried out in a 20 L spherical explosion tank. The results show that the addition of 75% (by mass) NaHCO₃/kaolin composite powder suppressant can achieve complete explosion suppression of aluminum powder. By comparing NaHCO₃ powder, kaolin powder and composite powder detonator, the composite powder detonator has a better effect on suppressing the flame propagation and explosion pressure of aluminum powder than the monomer powder does. The mechanism of the explosion suppression of aluminum powder by the NaHCO₃/kaolin composite powder inhibitor was analyzed.

KEYWORDS:

• NaHCO₃/kaolin composite
• aluminum powder explosion
• explosion suppressant
• suppression mechanism

Additional information

Funding

This work was supported by the China Postdoctoral Science Foundation [2018M632693]; National key R & D plan for the 13th five year plan [2017YFC0805200]; Qingdao science and technology plan project [19-3-2-6-zhc].