MINE HAZARDS - ASSESSING THE HAZARD OF COAL SPONTANEOUS COMBUSTION

摘要

Coal self-heating has been the subject of many investigations and extensive research has been carried out to better understand the relationship between coal quality and corresponding self-heating indices. R70 testing has been the benchmark in this field for the Australian and New Zealand coal mining industries and remains a key instrument in determining the propensity of coal to self-heat due to the extensive database of results. The R70 test however only accounts for the intrinsic coal reactivity, and because of this, developments have been made to the testing method to closer replicate site specific parameters. Extrinsic effects such as the mine ambient temperature, relative humidity of the air and the as-mined moisture content of the coal are now incorporated into an adiabatic simulation test (SponComSIM?). Gas evolution testing (SponComGAS?) can also be used to determine specific gas trends for a given coal sample in an as-mined condition for all the stages of a self-heating event. The gas trends recorded provide a unique signature that can be used on site to set appropriate trigger levels or alarm points for taking appropriate actions and implementing timely responses to mitigate against a spontaneous combustion event.