Stone Dusting Requirements and Options

This project was approved as an extension to the original project C8011 which investigated the level of stone dusting required to inert Australian coals for the purposes of preventing the propagation of a coal dust explosion. The main objective of the original project was to determine the minimum inerting requirements for Australian coals so as to prevent the propagation of a coal dust explosion in an underground mine.

Previous investigations using laboratory-scale equipment had found that, for a range of Australian coals, the individual inerting requirement varied from 83% to 90% total incombustible content (TIC), depending upon the coal and the ignition energy. It was also clear that the inerting requirements for individual coals were not correlated to volatile content or any other common coal property as previously thought. Only at very low volatile content was there a lower requirement, being 77% TIC at less than 10% volatile content.

This project was designed to validate a series of large-scale tests carried as part of the previous investigations. Large-scale testing of five Australian coals was undertaken at the CSIR Kloppersbos Explosion Research Centre in South Africa as a comparison against the results obtained in the laboratory. The results obtained indicated an inerting requirement of between 80% and 85%. This compares favourably with the results of laboratory testing at 5kJ.