Effectiveness of a high-temperature-programmed experimental system in simulating particle size effects on hazardous gas emissions in bituminous coal

In mining, coal is crushed into particles of various sizes. The size of these reactant particles affects the combustion risk profiles in mine safety, thus affecting industrial safety considerations. Therefore, this study explores the influence of particle size on hazardous gas emissions during the high-temperature oxidation of coal. A custom-designed and built high-temperature experimental system was developed and implemented. This practical experiment was conducted with the aforementioned system to analyze three coal samples from Huainan, Anhui Province, China. The gas concentration data were recorded for carbon monoxide, carbon dioxide, alkanes, and alkenes, with six different particle sizes, and covered a temperature range of 30 to 500 degrees C. As the oxygen consumption rate and normal temperatures are equally strong influential factors of spontaneous combustion, the oxygen consumption rate was simultaneously captured using the indicator gas growth rate method to determine the five characteristic temperatures was captured using the indicator gas growth rate analytical method. The five characteristic temperatures for the six particle sizes were determined as follows: critical, crack, active, speedup, and ignition.