Study on the characteristics of gas phase products in coal mine conveyor belt fire

•The combustion characteristics of coal mine conveyor belt were studied.•The gas phase products of conveyor belt combustion were examined in phases.•The products of three phases of conveyor belt combustion were thoroughly investigated.•The fire risk posed by conveyor belt burning is investigated. This study aimed to use the thermogravimetric infrared coupling (TG-FTIR) and cone calorimeter coupling techniques to analyse the Pyrolysis characteristics and fire hazard of conveyor belt during heating process based on different stages of the combustion process. The results demonstrate that the conveyor belt is melted and volatilized by heat in the first stage (200∼350 °C), and a cross-linking polymerization process ensues, with the primary gas-phase products being chlorine-containing compounds, aromatic acid esters, and HCl. In the second stage (350∼600 °C), the conveyor belt started to burn fiercely, redox reactions occurred, the primary gas-phase products added to hydrocarbons, Benzoic acids, aldehydes, amides, and a significant number of CO2, CO, H2O(g). The third stage (600∼700 °C) corresponds to the recession phase of combustion, when the concentration of most gas phase products decreases and the production of amides and ketones increases. As the intensity of thermal radiation increases, the mass loss, heat release rate, fire hazard, CO/CO2 generation rate and smoke also increase.