An experimental study on coal gas desorption laws with different particle size

Z H Wen, J P Wei, H T Zhang, S H Dai

COMPUTER MODELLING & NEW TECHNOLOGIES 2014 18(3) 44-48

School of Safety Science & Engineering, Henan Polytechnic University, Jiaozuo, China;
State Key Laboratory Cultivation Base for Gas Geology and Gas Control, Jiaozuo, 454150, China

Based on the self-designed coal containing methane gas desorption law experimental system and coal gas desorption kinetics law, the gas desorption law for different particle size coal under isothermal-isobaric condition are measured by combining combined simulation measurement with the theoretical analysis. The effect of particle size on coal gas desorption laws are obtained through fitting analysis on experimental data: 1.Under the same sorption and desorption conditions, coal particle size was inversely related to total desorption gas amount in the same period. 2. For coal with any particle size, the gas desorption amount firstly increased as time, and finally reached the maximum value, which was equal to the gas sorption amount unit per mass. 3. For coal with higher gas and coal outburst risk trend, the effect of particle size on initial desorption velocity and total desorption amount with time was less. 4. Within the limit particle size, the gas initial desorption velocity had a negative relationship with particle size. Finally we theoretically analysed the effect of particle size on coal gas desorption laws.