采动条件下煤层瓦斯赋存状态变化以及CH_4对煤体温度的影响

Occurrence Change of Coal Seams Gas Under Mining Conditions and Coal Temperature Influenced by CH4

采动条件下，尤其足在深部开采的条件下，采动引起煤层赋仔状态的变化，自然引起煤中瓦斯赋存状态的变化。在煤层赋存的瓦斯量中，通常吸附瓦斯量占80％～90％。随着瓦斯压力的增大，瓦斯含量也相应地升高。相应的在相同的瓦斯压力下，随着温度的升高，瓦斯禽鞋降低。在瓦斯压力比较低时，吸附瓦斯量占绝大部分；随着瓦斯压力的增大，吸附瓦斯量渐趋饱和，而游离瓦斯所占的比例则逐渐提高。在深部地层中，当瓦斯压力较高时，煤层和岩层孔隙中所含有的游离瓦斯量往往可以达到相当大的数值。而随着煤中游离瓦斯含量的增加，CH4和CO2，（主要是CH4）对煤体的升温起到了促进作用，增大了煤体发生自燃的可能性。分析结果对我国井工深部开采瓦斯管理具有理论指导意义。

Under mining conditions, particularly under deep mining conditions, coal mining caused the oecurfence changes of coal seam naturally caused coal gas occun＇ence changes. In the coal bed gas volume, gas ad- sorption usually accounts for 80% - 90%. Along with the increase of gas pressure, and gas content of the corresponding increases. Corresponding to the same gas under pressure, with the rise of temperature, and gas content reduces. The gas pressure is low, the adsorption gas accounts for the majority. With the increase of gas pressure, gas adsorption capacity is becoming saturated, while the share of free gas ratio will be gTadually increased. In the deep strata, when the gas pressure is higher, coal and rock porosity which contains free gas volume can often be a very large value. With the ircrease of free coal gas content, CH4 and CO2 （primarily CH4） on the coal warming play a role, increase the possibility of coal spontaneous combustion. The results have theoretical significance for deep mining gas management.