Underground » Detection and Prevention of Fires and Explosions
The application of dry limestone dust or stone dust in sufficient amounts is the accepted method of inertising coal dust deposited in coal mine roadways thereby preventing the occurrence or propagation of a coal dust explosion.
The use of slurry dusting, where the stone dust is applied in a water-based slurry to the walls, floor and roof of coalmine roadways, has become more commonly used in Queensland. Doubts have been expressed with regard to the suitability of the use of such a method especially in the case of a “weak explosion” in which the inerting material may not become airborne.
A thorough search of pertinent literature has been conducted to determine the extent and results of previous work into aspects of stone dust that could have relevance to the use of slurry or sprayed wet stonedust.
The study outlined the development of sampling methods that more closely represented the “weak” explosion scenario. These sampling methods were then used to evaluate the suitability of the use of “slurry dusting “ as a replacement for normal stone dusting methods or as a supplement to such methods.
Previous work indicating the potential hazard of using slurry dusting on its own was confirmed and recommendations with regard to the application of stone dust as well as the sampling of roadway dust were then proposed.
On the whole the study found that there was a use for slurry stonedust in the mining environment but that it should not be seen as a replacement for dry stonedust to inertise coal dust in areas of high coal dust deposition.