Study on transport characteristics of multi-component gaseous mixtures through coal pore

The study of gas movement in coal pore is of great significance to the accurate assessment of internal fire risk.The pore structure of coal provides a suitable medium for gas storage and movement.The gas mixture of gases released from the coal self-heating can move into the coal pore and be adsorbed by coal.In the paper，the activities of multi-component gases released from coal self-heating in the pore of coal particles are experimentally studied.The results show that the concentrations of various gases at the outlet of the reactor in the coal self-heating experiment determine the characteristics of coal self-heating.The main components of the released gaseous mixtures are gaseous oxides (CO and CO2) and pyrolytic gases (hydrocarbons and H2).These gas mixtures can be used for risk assessment of endogenous fire in coal mine.The results also demonstrate that the adsorption characteristics of mixed gases in coal can be determined by the ratio of gas concentration at the outlet to gas concentration at the inlet of the adsorption column.The concentration of each component gas at the inlet and outlet is related to the physical and chemical properties of gas molecules.Gases with lower critical temperature are not easily adsorbed in coal pore and gases with smaller molecular sizes are more easily adsorbed than those with larger molecular sizes.