No.40 Measurement of air oxidation rate of coal at 60 to 80℃

Abstract

Low rank coals are susceptible to spontaneous combustion, but they must be heated over a critical temperature of around 70 ℃ before spontaneous combustion starts. This work focused on the adsorption of water vapor as a possible mechanism of the temperature increase up to the critical temperature. When the coals pre-dried and cooled to 38 ℃ were exposed to a saturated air at 38℃, the coal temperatures increased up to over 60℃ in a minute or so. This work showed that the rapid adsorption of water vapor will be a cause of temperature increase leading to the spontaneous combustion of low rank coals.