Response Characteristics of Coal Adsorbing CH₄ Capability Under Variation of Temperature and Pressure

In order to study the response characteristics of adsorption capability of coal/CH4 at variation of temperature and pressure, the isotherm tests were done at different temperatures (-20, -10, 0, 10,20 ℃), using the samples from VI_15-17 coal bed in Pingdingshan Mine, we processed the experimental data by MATLAB. Results showed that methane adsorption capacity in coal is decreased with the increasing of pressure under specific temperature and tends to be stabilized when the pressure rises to specific point. Before the pressure increases to 6.3 MPa, pressure has effect on adsorption capacity primarily if pressure rises to 8 MPa from 0 MPa and temperature increases to 20 ℃ from -20 ℃. Temperature has influence on adsorption capacity observably when the pressure is higher than 6.3 MPa. During the adsorption capacity is influenced synthetically by temperature and pressure, pressure restricts the influence of temperature on adsorption capacity and temperature also restricts the influence of pressure on adsorption capacity.