Hazard evaluation of sulphide dust explosions

Abstract

Experiments were conducted in a 1 m 3 explosion chamber and the explosibility parameters for sulphide dust were determined and compared to other types of dusts. The severity of the explosions, as indicated by the K St value, was scaled by comparing the experimental results from different sizes of explosion vessels. The K St value was found to increase with the volume of the explosion chamber, as expected for systems whose level of turbulence increases with increasing chamber volume. Explosive limits for a typical sulphide dust were obtained by examining the effect of dust concentration on the explosibility parameters. The lower explosive limit was found to be 300 g/m 3 for a sulphide dust with a sulphur content of 29.86% by weight. To simulate the ignition source in underground mines, explosives were used to ignite sulphide dust clouds in the 1 m 3 chamber tests and an ignition criterion was developed for mining explosives that do not contain aluminum. It was found that the minimum ignition energy can be expressed as the product of the heat of explosion and the minimum weight of explosive required for the ignition of the dust.