为了系统研究煤层气(甲烷)解吸动力学的影响因素,选用川南地区的无烟煤,设计了不同压力、温度、粒度和湿度下的煤层气解吸动力学实验。采用高温高压煤层气吸附/解吸测试系统进行实验,并拟合实验结果获得了不同条件下的扩散系数。研究表明:压力和温度越高,甲烷解吸量和解吸速率越大;粒度越大,甲烷解吸量和解吸速率越小;低于平衡水含量时,湿度增大,甲烷解吸量和解吸速率降低;甲烷扩散系数拟合结果揭示,扩散系数随压力增高而减小,随温度升高而增大,随湿度增大而减小。
In order to study the affecting factors for coalbed methane desorption kinetics,desorption kinetics tests were designed under different pressure,temperature,grain size and moisture with anthracite from South Sichuan Coalfield.A self-made HTHP coalbed methane desorption tester was applied in desorption kinetics experiments.Diffusion coefficient was got by fitting result of test.Gas desorption capacity and rate of granular coal increase with increasing adsorption equilibrium pressure and temperature,and decrease with increasing grain size and moisture.The fitting result of diffusion coefficient reveals that diffusion coefficient is increasing with temperature but decreasing with pressure and moisture.