The Experiment on the Features of Ultrasonic Vibration Stimulating the Absorption and Desorption of Methane in Coal

Abstract

Through adopting the self-explored experimental system of ultrasonic vibration, this experiment studied the adsorption and desorption characteristics of methane in coal under the sound field varying in frequency and sound intensity. Results of the research showed that the methane absorption in coal reduces when being placed in the sound field, and the amount of absorption reduces as the sound intensity increases. The amount of methane desorbed in coal increases under the working of sound field, which indicates that the effect of sound field can promote methane desorption and diffusion. the adsorption 、desorption law of methane in coal are the same under the condition of sound field and no sound field, The absorption model can be described by the Eequation D-R、Langmuir Equation、Freundlich Equation and Equation BET. Plus, the Equation D-R、Langmuir Equation can better describe the law of methane absorption in coal. Desorption model can be expressed by empirical formula、diffusion model and percolation model, and the diffusion model can better describe the desorbing characteristics of methane. These results can provide theoretical principles to improve the rate of coal seam extraction under ultrasonic vibration.