Research on Cracks and Gas Extraction Technology in Thin Coal Layer Mining
In response to the gas outburst situation in a thin coal seam of a mine in Shanxi,theoretical analysis and numerical simulation methods are used to analyze the gas extraction plan.The results indicate that the annular crack circle on the roof of the thin coal seam working face is very small and cannot penetrate the upper sub key layer.The gas concentration generated by the crack cannot develop in the sub key layer and upper rock layer.The lower coal body of the coal seam is one of the most effective methods to prevent gas exceeding the limit in the upper part of the coal seam,but there is also the disadvantage of insufficient drilling depth.In practical applications,the extraction project should be located in the crack zone below the sub critical layer.
NETL
NSTL
万方数据
维普
