Experimental Study on Gas Extraction of Adjacent Coal Seams by Upward Drilling in High-located Drainage Roadway

In order to enhance extraction effect of the relieved methane from the upper adjacent coal seams,and to reduce the working face gas emission when the protected layer mined in the short-distance coal seams,a extraction method with the upward drilling holes located in the high-located drainage roadway was proposed.The principle and related technology of the method were discussed,and engineering experiment was taken at the Jinjia coal mine in the Guizhou Panjiang refined coal Co,Ltd.The result shows that the upward drilling hole in high-located drainage can effectively extract the relieved methane from the upper coal seam and can improve the extraction effect;early stage of mining in the next layer of protection face,the gas extraction content using upward drilling hole is small and low concentration;the extraction effect in medium stage is good and the post-extraction effect becomes worse.