Investigation of Sensitizers Used in Ammonium Nitrate Commercial Explosives

Successful detonation of commercial explosives due to the low sensitivity of these compounds requires the use of sensitizing agents in the formulation. The sensitizer improves the initiation, velocity of detonation and performance of the explosive by improving the propagation of the shock wave caused by the detonation reaction. The type of sensitizer used in commercial explosives is one of the important factors in determining the cost of production as well as the safety, performance, shelf-life and application characteristics of commercial explosives. In this paper, various sensitizing agents that are currently used, including aluminum powder, monomethyl ammonium nitrate, chemical gassing, microballoons and porous ammonium nitrate prills, have been investigated. In the past, molecular explosives such as nitrocellulose and TNT were used to sensitize commercial explosives. In order to reduce the problems and risks of production, transportation and use, self-explosive materials were gradually replaced by new methods. The use of aluminum powder or organic nitrate amines in combination with micrometer air bubble sources such as microballoons, chemical gassing and porous materials completely release the high-energy capacity of commercial explosives along with increasing performance, adjusting production costs and increasing efficiency of blasting operations. Styrofoam, perlite and some other porous materials have also been tested but are not operational due to some problems. Optimal sensitizing agents maintain the advantage of relatively low sensitivity of commercial explosives and at the same time the desired initiation of these compounds by using suitable primers in blasting operation. Thus, the need for higher hazard class compounds for initiation of commercial explosives is eliminated and the cost of production is reduced.