水力压裂技术在打通一矿低透气性突出煤层中的试验研究

Experimental Study of Hydraulic Fracturing Technology in Outburst Coal Seam with Low Permeability in Datong No.1 Mine

随着矿井开采深度的不断加大,煤层透气性系数逐渐降低,严重威胁着矿井的生产安全。针对打通一矿7#、8#主采煤层低透气性、瓦斯难以抽放的问题,对高压水力压裂技术进行了分析研究。现场试验中对压裂孔的施工技术、布孔方式、封孔工艺,以及安全组织措施进行了分析和实施,并对高压水力压裂影响范围和效果进行了考察,结果表明:煤层的透气性、平均瓦斯抽采浓度及抽采纯量显著增大,减少了抽采时间,降低了煤与瓦斯突出危险性。

With the increase of mining depth of the mine, the gas permeability coefficient of coal seams reduced gradually, which seriously threated to the safe production of the mine. To counter to the problems of low gas permeability and difficult gas drainage of No. 7 and 8 coal seams in Datong No. 1 Mine, the high-pressure hydraulic fracturing technology was analyzed and studied in this paper. In the field tests, analysis and implementation were made on the drilling technology of hydraulic fracturing holes, the hole arrangement, the hole sealing technology and the safety measures, and investigation was conducted on the influence scope and the effect of hydraulic fracturing measure. The results showed that the gas permeability of coal seams, the average gas drainage concentration and the pure gas drainage volume significantly increased, the drainage time decreased and the coal and gas outburst hazard reduced.