Research On The Sealing Hole Depth Of 3# Coal Seam Gas Drainage In Licun Mine

Our country’s coal resources is very complex, and almost all of the mine have a lot of gas. These mine’s gas is difficult to control, so our country’s coal resources is very dangerous in exploitation. Gas drainage play an important role in reducing gas and guarantee the mine normal exploitation, while the sealing is an important part of the gas drainage, in which the depth of sealing for the gas drainage has a significant influence.Currently, there are a variety of methods to measure the depth of borehole sealing,however these methods is difficult to reach the need of engineering in operation and accuracy. Based on the relationship between seem stress, gas pressure, mine permeability and the drop cure of borehole pressure, using different depth have different decline cure and FLAC3 D, we get a new way to measure the depth of pressure relief zone, concentrated stress zone and original stress zone. We did the text and experimental study in 3#coal seam of Licun mine Lu’an Group, combined with drilling bits index method, gas quantity of desorption in underground and the result of drainage parameters. We get the reasonable sealing depth which is 12 m. This paper provide an important theoretical basis and a method for determining the depth of drilling in Licun mine.