分段水力压裂技术提高煤层块煤率的试验研究

为了解决陕北侏罗纪厚硬煤层综采能耗大、块煤率低的问题，采用水力压裂造缝技术提高煤层开采的块煤率、降低煤尘。以陕北某国有煤矿为例，在矿区回采工作面进行水力压裂试验及分析，并对试验段和非试验段的块煤率、煤层截割比能耗、含水率和工作面粉尘浓度进行现场统计，得出:水力压裂技术在煤层中的起裂压力、时间及扩散半径等参数。通过回采试验区和非试验区的对比，得出采用水力致裂煤层后，采煤块煤率、工作面粉尘浓度具体的改善程度。研究表明，对煤层进行超前水压预裂，具有清洁高效、提高块煤率及降低煤尘等优点，采用分段水力压裂技术可大幅度提高单孔的造缝率，具有很好的推广价值。

Experimental study to improve ratio of lump coal with subsection hydraulic fracturing technology

In order to solve the problems of high energy consumption and low lump coal rate in fully mechanized mining of Jurassic thick and hard coal seam in northern Shaanxi，hydraulic fracturing technology is adopted to increase lump coal rate and reduce coal dust in coal seam mining.Taking a state-owned coal mine in northern Shaanxi as an example，hydraulic fracturing experiments and analysis were carried out in the mining face，and the lump coal rate，specific energy consumption of coal seam cutting，water content and dust concentration in the test and non-test sections were counted on the spot.The following conclusions are drawn:parameters of hydraulic fracturing technology in coal seam，such as initiation pressure，time and diffusion radius，etc.By comparing the mining test area with the non-test area，the concrete improvement degree of lump coal rate and dust concentration in working face is obtained after hydraulic fracturing coal seam is adopted.The research shows that the advanced hydraulic fracturing of coal seam has the advantages of cleanliness，high efficiency，increasing lump coal rate and reducing coal dust.The fracturing rate of single hole can be greatly improved by using the subsection hydraulic fracturing technology，which has good popularization value.