OFFICIAL As noted earlier, the ARC simulates a worst-case scenario, like blast holes, where heat and gases cannot easily escape. In the ARC testing, the onset of thermal runaway was 10 oC lower than in the isothermal test standard temperature of 55 oC demonstrating that selfheating and thermal runaway initiate at lower temperatures under conditions where heat dissipation is suppressed. The HWS method is primarily intended as a rapid screening tool to rank relative thermal stability and identify onset temperatures, rather than to determine time-to runaway starting from a target temperature (Stoessel, 2008). To investigate the time to thermal runaway in the reactive ground system and an inhibited system the iso-aging mode was used. Iso-aging is a single cycle of the heat wait search test that is used to determine time to thermal runaway from an initial set temperature. Figure 8:Heat Wait Search Traces with AN, AN + Pyrite and AN + Pyrite + Weathering byproducts overlaid. A lower onset temperature indicates lower thermal stability. It was noteworthy that the sample with weathering byproducts reacted at 45 oC
RkJQdWJsaXNoZXIy MTM0Mzk2