Laboratory experimental study on water-soaked–dried bituminous coal’s thermal properties

• DOI: 10.1007/s10973-019-08769-6
• Publication Date: 2019-09-11T06:53:32Z
• Authors: Xiao-Wei Zhai; Wen-Jun Pan; Shi-Bo Wu; Hui Ge
• Keywords: 13. Climate action; 02 engineering and technology; 0204 chemical engineering; 7. Clean energy

In the process of multi-seam mining, the measure of water exploration is usually employed for the upper coal seam to prevent and control water accumulation. The residual coal immersed in water for a long time in the upper layer is dried under the action of air leakage, leading to the enhancement of the risk of coal spontaneous combustion. Therefore, it is necessary to study the water soaking–drying process (WSD) on the spontaneous ignition characteristics of coal. In this study, a laser thermal conductivity analyzer was used to investigate the changes in thermal properties of bituminous coal collected from mines in western China after WSD. The results show that compared with the raw (unsoaked) coal samples, the thermal diffusivity, specific heat capacity, and thermal conductivity of the bituminous coal are considerably reduced after WSD; the maximum reductions in the three parameters are 11.11%, 6.64%, and 12.39%, respectively. These reduced thermal parameters indicate that after WSD, bituminous coal is more prone to self-heating, resulting in an increase in the rate of coal–oxygen compound reactions and a significantly increased risk of spontaneous combustion.