Abstract: To investigate the relationship between the permeability and temperature of tectonic coal containing gas, a series of tests on tectonic coal samples containing gas is carried out at different stress conditions using a self-developed triaxial hot-fluid-solid coupling seepage testing device. Experimental results show that the permeability of tectonic coal samples decreases with the increase of temperature, and there is a negative exponential function relation between permeability and temperature. Moreover, the relationship between the permeability loss rate and the effective stress follows the Boltzmann distribution with the variation of experimental temperature. There exists an effective stress threshold of approximately 4.515 MPa for the permeability loss rate. There are two stages identified in permeability change of tectonic coal, i.e. the accelerating stage and the smooth stage, and the transition temperature from the accelerating phase to smooth phase is about 45 ℃. Within the range of 21-80 ℃, the sensitivity order of the permeability coefficient is 10-2, which means the effect of temperature on permeability of tectonic coal sample is not obvious. At the same time, the increase of effective stress results in the decrease of the temperature sensitivity coefficient.

Key words: tectonic coal, permeability, effective stress, temperature sensibility