High temperature and pressure methane adsorption characteristics and adsorption kinetics of shale

To understand the methane adsorption and adsorption kinetics characteristics of shale under high tempera- ture and pressure,some adsorption and adsorption kinetics experiments were carried out with 0-50 MPa,temperature ranges at 40. 6,60. 6,75. 6 and 95. 6 ℃ . Adsorption isotherms and kinetics curves were obtained and a detailed analy- sis was performed. Results show that all the excess adsorption isotherms have a maximum value over 0 -50 MPa;the higher the temperature,the bigger the pressure,which corresponds to the maximum of one excess isotherm;there exists a critical temperature for each isotherm,and if the test temperature is greater than the critical temperature,the excess adsorption isotherm is monotonically increasing with pressure;the adsorption equilibrium time is about four hours for the 40-100 mesh number shale;Bangham kinetics equation is more suitable for describing the kinetic process of meth- ane adsorption.