Spontaneous ignition characteristics of coal in a large-scale furnace: An experimental and numerical investigation

A comprehensive understanding of the spontaneous combustion characteristics of coal in various surroundings is necessary for developing reliable test platform and predictive models. In this study, the characteristics of oxidation and self-heating combining various gas flow equations in loose coal were investigated separately and used to simulate the experimental procedure of spontaneous combustion. The main focus was to investigate the effect of thermal boundary on temperature profiles as well as spontaneous combustion period. The results showed that the numerical approach was validated by comparison with the test data. Furthermore, the model based upon Brinkman equation showed a higher accuracy, which indicated that airflow behavior influences the,balances of coal oxidation and heat dissipation, thus impacts the temperature profiles of loose coal. The areas of high temperature zones would be evidently expanded and the spontaneous ignition time would be significantly accelerated if the thermal exchange between the coal and its surroundings decreased. Our results, especially for the field of engineering, have substantial effects for grasping and controlling coal spontaneous combustion disaster. (C) 2016 Elsevier Ltd. All rights reserved.