Analysis of Factors Affecting Dust Explosion

Abstract

In the US alone, the Chemical Safety Board reported 281 dust explosions that occurred between 1980 and 2005; resulting in 199 fatalities and 718 injuries. The basic factors required for a dust explosion are: a combustible dust, suspension of dust in high concentration, atmospheric oxygen, and an ignition source. Typically it is very difficult to eliminate factors in a factory setting handling dust particles. This study focuses on the electrostatic charge produced when dust particles are transported pneumatically in a pipe. This electrostatic charge can lead to ignition source and hence cause a catastrophe. Humidity is found to be in direct correlation with electrostatic charge. At a higher humidity, conductivity increases and the charge is more likely to dissipate. Besides looking at related works of other researchers (who looked at electrostatic charges and the influence of humidity on them), experiments were also carried out to analyze the influence of charge on different powders when suspended in different environment and the charge decay time at low humidity as well as at high humidity. It was confirmed that humidity mitigates the situation by decreasing the charge decay time (unless the powder is hydrophobic).