山西省上煤组瓦斯含量和气成分规律研究

Gas Content and Gas Composition Law of Upper Coal Formation in Shanxi Province

随着煤层瓦斯开采规模的逐渐扩大,抽采出来的瓦斯含量和CH_(4)的体积分数在逐渐降低。为了能更好地利用和防治瓦斯,收集整理了山西省66个县市上煤组的瓦斯气成分数据5830个,分析得出大同煤田、宁武煤田和霍西煤田的瓦斯含量及CH_(4)的体积分数较低;河东煤田南部和沁水煤田北部和南部瓦斯含量及CH_(4)的体积分数较高。随着煤层深度逐渐增加,挥发分含量降低,对应的瓦斯含量逐渐升高,气成分中CH_(4)的体积分数逐渐升高,N_(2)和CO_(2)的体积分数逐渐降低,重烃的体积分数几乎不变。

With the gradual expansion of coal seam gas mining scale,the gas volume and CH_(4) volume fraction are gradually decreasing.In order to make better use of and prevent gas,this paper collected 5830 gas composition data of upper coal formation in 66 counties and cities of Shanxi Province.The analysis has showed that the gas content and CH_(4) volume fraction in Datong Coalfield,Ningwu Coalfield and Huoxi Coalfield are low;the gas content and CH_(4) volume fraction are higher in the south of Hedong Coalfield and the north and south of Qinshui Coalfield.As the depth of coal seam gradually increases,the volatile content decreases,the corresponding gas content gradually increases,the CH_(4) volume fraction in gas component gradually increases,the N_(2) and CO_(2) volume fraction gradually decrease,and the volume fraction of heavy hydrocarbons is almost unchanged.