煤层注氮驱替甲烷促排瓦斯的试验研究

〖HT5H〗摘〓要：〖HT5K〗实验室研究了山西阳泉无烟煤在30 ℃恒温下注入N2对吸附平衡煤样中CH4的竞争吸附解吸特性，结果表明混合压力高于225 MPa后，CH4吸附量开始下降。在阳泉煤业集团石港矿业公司井下进行了煤层注氮驱替甲烷促排瓦斯的试验研究，结果表明，注氮16 h后距离2 m以内的钻孔自然排放纯瓦斯流量提高了2倍以上，煤体解吸气体中CH4浓度由9729%减小到7966%，氮气浓度由080%增加到1319%，煤层瓦斯含量由977 cm3/g减少到868 cm3/g,起到了预排瓦斯的效果。

Experimental Study on Technology of Accelerating Methane release by Nitrogen Injection in Coalbed

The displace desorption charactereristics for methane adsorption balance coal samples of Yangquan anthracite were studied by nitrogen injection at 30℃ in laboratory. In order to displace and accelerating release coalbed methane, a series of underground experiment of nitrogen injection in coalbed were also completed in Shigang coal mine of Yangquan Ming Group. The results indicate that nature pure gas flow in bore hole within 2 meters increased more than 2 times after nitrogen injection 2hours, and methane concentration desorption form coal sample decreased form 97.29% to 79.66%, nitrogen concentration increased from 0.8% to 13.19%. Correspondingly, residual gas content in coal seam decreased from 9.77 cm3/g.r to 8.68cm3/g.r. In conclosion, the technology of nitrogen injection in coalbed received a good effect in accelerating methane release.