Sulphide dust ignition resistant explosives

CIM Bulletin, Vol. 87, No. 980, 1994

M. Rispin, ETI Explosives, North Bay, Ontario, and J.R. Dalton, Explosives Technologies International

Blasting in high sulphide content ores presents at least two major safety considerations: (1) compatibility of the explosives with the ore while resident in the borehole; and (2) introduction of a flame and shock producing explosive into this environment, while minimizing the risk of reactive ignition in the chemical reaction products/sulphide dust cloud resulting from the detonation. This paper will discuss only the second consideration, i.e. post detonation reactivity. The ETI (Explosives Technologies International) Technical organization, in consultation with the U.S. Bureau of Mines, reasoned that the most relevant considerations in the development of an explosive for this application are: • • • • • • Obviously, not all of these are totally independent properties, i.e. increased sensitivity will reduce the probability of low order detonation as will higher energy levels. However, these considerations were examined separately as if they were independent. minimization of reactive gaseous detonation reaction products; flame duration reduction; flame temperature reduction; increased explosive sensitivity; reduced probability of "low order" detonation; and maintenance of energy level as high as possible.

Keywords: Safety, Sulphide dust explosions, Underground mining.