煤层温度与瓦斯赋存状态和抽采率关系的实验研究

摘要

In order to study the effect of temperature on gas occurrence state and gas drain-age,the gas adsorption and desorption changes of coal samples were studied at different tempera-tures.According to the experimental data,the regression equations of Langmuir adsorption con-stants a and b varying with temperatures and diffusion velocity varying with temperatures and time.The experimental results showed that the adsorption constants a and b decreases with the increase of temperature.Moreover,the constant a conforms to the quadratic function relation with the temperature,and the constant b accords with the linear function relation.In addition, the desorption capacity,the diffusion velocity and total diffusion amount increase with the rise of temperature under the same pressure.The higher the temperature,the larger the diffusion veloci-ty.While at the constant temperature,the diffusion velocity attenuates with negative exponent for a prolonged time.The experimental data and related physical principle showed that the exter-nal electric field,the alternating electromagnetic field and the power ultrasonic method can im-prove the coal seam temperature,promote the gas desorption and increase the diffusion rate,so the gas drainage rate can be enhanced.The greater the initial gas diffusion velocity,the higher the coal seam outburst danger.Therefore,the decreased coal seam temperature can reduce the coal seam outburst danger.%为了探索温度对瓦斯赋存状态与抽采效果的影响,实验研究了煤样在不同温度下的吸附解吸变化规律。根据实验数据,给出 Langmuir 吸附常数 a 和 b 值随温度变化的回归方程及扩散速度随温度、时间的回归方程。实验结果表明：吸附常数 a 和b 值都随温度的升高而降低,a 随温度变化符合二次函数关系,b 则符合线性函数关系；相同压力作用下,解吸量、扩散速度和总扩散量随温度的升高而增大；温度越高,扩散初速度越大；温度不变时,扩散速度随时间延长呈负指数迅速衰减。根据实验结论和相关物理学原理,煤层外加的电场、交变电磁场、功率超声波等方法能提高煤层温度,具有促进瓦斯解吸和增大扩散速率的作用,能提高瓦斯抽采率；瓦斯扩散初速度越大,煤层突出危险性越高,所以降低煤层温度,可以减小煤层的突出危险性。