Tenth International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions pages:1093-1101
XISHPMIE location:Bergen date:10-14 June
As a dust explosion is regarded as a serious hazard in the industry, knowing the sensitivity of combustible dusts helps to calculate the explosion risk. Also mixtures of a less flammable dust with a combustible dust are often encountered in the process industries. One of the
important parameters in determining the ignition sensitivity is the minimum ignition energy (MIE). The aim of this work is to determine crucial ignition energies for different types of combustible dusts of various particle sizes. Experiments are performed to determine the
minimum ignition energy of pure dusts and also of different powder mixtures in air. They illustrate that by adding a small amount of a highly combustible powder (such as niacin,
lycopodium and metal powder) with a less flammable powder (such as wood, cacao and South African coal) has a considerable effect on the MIE. There is a significant decrease in minimum ignition energy when the fraction of the highly combustible dust exceeds 10%.
After mixing with more than 50% of the highly combustible dust, the minimum ignition energy decreases gradually. In addition for the ignitable mixtures, the minimum ignition
energy was calculated by means of a harmonic model and gave a satisfactory agreement with the experimental obtained values. It has notably been shown that the MIE of solid/ solid mixtures decreases remarkably when the highly flammable dust is added.