Experimental study on temperature change law of pulverizedcoal during adsorbing methane

This paper is devoted to study the temperature change law and mechanism of pulverized coal in the process of adsorbing methane, a combination of theoretical analysis and experimental research is adopted.Based on the Joule-Thomson effect and the adsorption heat effect, temperature changes in adsorption of pure methane under compression, expansion, and different pressure were compared. The results show that when filling the pulverized coal chamber with a gas tank, the gas temperature in the chamber rapidly increases by 15 ℃ under different pressuredue to the methane Joule-Thomson effect and decreases by 6 ℃when releasing the chamber. The process of adsorbing methane from pulverized coal is exothermic, with temperature rise of 2～8 ℃. The temperature change depends on methane adsorption equilibrium pressure.It is also found that during the process of methane adsorption, ambient temperature change is a result of the exothermic and throttling effects of adsorption reaction. The research results provide a reference for selection of temperature indicators for underground gas disaster prediction.