Experimental study on thermal effect and gas release laws of coal-polyurethane cooperative spontaneous combustion

This paper presents a research on the kinetics and gas release laws of the cooperative spontaneous combustion of coal-polyurethane binary system by means of thermogravimetric analysis and spontaneous combustion simulation experiments. The coal-polyurethane binary system is more prone than individual samples to combustion. The polyurethane mass fraction has a great influence on the cooperative spontaneous combustion process. As the polyurethane mass fraction rises, the activation energies of oxygen absorption stage and pyrolysis stage decrease. The combustion residues of coal-polyurethane binary system scorches into lumps and the surfaces of the particles become rougher. During spontaneous combustion, the initial release temperatures of the four gases CO2, CO, C2H6 and C2H4 drop as the polyurethane mass fraction increases. The gas release amount of them increases with increasing polyurethane mass fraction. And the amount of CH4 decreases as the polyurethane mass fraction increases. The CO/CO2 ratio with temperature for different polyurethane mass fraction have the same trends. The results of this study have implications concerning polyurethane materials application and fire protection in coal mine.