Difference Between Gas Adsorption and Desorption of Coking Coal Under the Condition of Variable Temperature

To study whether adsorption and desorption exist reversibility or not has a great significance for the gas drainage, in order to study this phenomenon well and try to minimize the interference of other external factors on the experimental results, this paper adopts the airtight environment in the whole process, through the reversibility of cooling-calefactive process by the control of high and low temperature alternating test chamber, to realize the cooling adsorption and calefactive desorption process of coal core. Experimental research shows that the cooling adsorption and calefactive desorption process of coking coal exist some difference. The data measured in adsorption process can not be used simply to decide the CBM drainage amount. With the increase of initial equilibrium pressure, the difference of air content in the coal sample will present an increased trend; for an experiment group, the difference of air content also present an increased trend as the temperature rise, and this trend will be obvious when the initial equilibrium pressure increases to a certain degree.