Study On The Minimum Ignition Energy And The Lower Explosive Concentration Of Aluminum Powders And TNT Dusts

Dust explosion has been concerned, because of destructive and high incidence.Aluminum power is widely used in traditional industry and military industry, However, thereare significant risks of fire and explosion during the processes of production and storage,because of its flammable property, lower explosion limit and lower ignition energy. TNT iswidely used in ammunition and engineering blasting. However, the TNT dust will be a fuse ofa huge disaster by accidental fire.The minimum ignition energy and lower explosion limit of dust are important parametersto determine whether dust explosion occurrence and the degree of difficulty of dust explosion.The minimum ignition energy and lower explosion limit of aluminum power and TNT powerwere tested in this article. The conclusions are as following:(1) Effect of dust concentration on minimum ignition energy limit were studied. Thedust concentration is an important factor affecting the minimum ignition energy. There is asensitive dust concentration and at this dust concentration, the ignition energy is lowest. Thesensitive concentration of aluminum dust of40-42μm is1066g/m~3, the correspondingminimum ignition energy is133.8mJ. The sensitive concentration of aluminum dust of78-80μm is500g/m~3, the corresponding minimum ignition energy is15.75mJ.(2) Effect of particle size on minimum ignition energy and lower explosion limit werestudied. The particle size is the monotony factor to affect the minimum ignition energy andlower explosion limit, the minimum ignition energy and lower explosion limit decrease withdecreased of the particle size. The aluminum dust with particle size of15-17,40-42and55-57μm were studied, the minimum ignition energy are32.94,133.8and198.6mJ, thelower explosion limit are35,60and70g/m~3.(3) The lower explosion limit of78-80μm TNT dust is25g/m~3, and the minimum ignition energy is15.75mJ. The lower explosion limit of TNT dust is lower than that of blackpower, RDX and HMX is measured in the experimental investigation on minimum ignitionenergy of dust concomitant with power and explosive material by Wang Peilan and so is theminimum ignition energy, the process of TNT production should take precautions.