Investigation of the thermal behaviour of pre-oxidation coal in deep mines

As mining continues to increase in depth, the problem of pre-oxidation coal (POC) spontaneous combustion (PCSC) in deep mines is coming to the fore. The effects of thermal ambient temperature and pre-oxidation temperature (POT) on the thermal mass loss (TG) and heat release (DSC) characteristics of POC were studied. The results show that the oxidation reaction process is found to be similar among the coal samples. The majority of mass loss and heat release from the oxidation of the POC is in the stage III and decreases with increasing thermal ambient temperature, while the combustion properties change in the same way, indicating a consequent reduction in the risk of spontaneous combustion. The higher the POT, the more the critical POT tends to be at a lower POT at a higher thermal ambient temperature. It can be demonstrated that higher thermal ambient temperatures and higher POT lower the risk of spontaneous combustion of POC.