Comprehensive research method for explosive coal dust

Abstract

The article briefly analyses the explosion and fire hazard properties of coal dust of different dispersions. It is emphasised that many experts working in the field of explosion protection and industrial safety pay insufficient attention to changes in the properties of the dust when reducing its dispersity. It is suggested to develop a new, complex methodology based on the dispersed composition of coal dust. The authors suggest to put methods of special sample preparation and dispersing of samples in two stages as a basis of the complex methodology. To do research with the help of thermal synchronous analysis of the smaller fractions, the authors propose to regrind the coal fraction obtained after the cone crusher in an analytical mill. To exclude adhesion of particles due to the process of static charges accumulation it is suggested to use impactless sieving machine of Retsch company which allows to take out the accumulated charges of static electricity. The coal dust fractions obtained after sieving were sent for granulometric analysis by a dynamic image processing method in CAMSIRE and by an optical microscopic method using a LEICA DM 4000 with image scope colour processing. A simultaneous thermal analysis was performed selectively for fractions smaller than 1000 μm. This was carried out with an STA 449 F3 and NETZSCH Proteus termal analysis application software. The authors consider that the obtained results allow to conclude that it is further expedient to carry out research work in this direction and will make it possible to develop recommendations aimed at prevention of coal dust aerosol explosions.