Analysis on Sealing Method and Sealing Materials of Gas Drainage Borehole

Abstract

With the increase of gas drainage volume and gas drainage requirement of coal seam in China, more and more attention to gas drainage effect of coal seam is paid. The gas flow law and borehole sealing mechanism are briefly described, the borehole sealing technologies of different materials are analyzed and the requirements are obtained as follows: 1Sealing materials shall have permeability. 2Sealing materials shall have expansion. 3The strength and hardness of sealing material can not be too high. 4Sealing materials are compact; sealing materials shall have certain strength. 5Sealing materials can be obtained easily and their price shall be low. 6Sealing process is simple and is constructed easily. Finally, the high polymer foam sealing technology, the mechanical elastic sealing technology, borehole packer sealing technology, the new pressure grouting hole sealing technology, yellow clay borehole sealing technology and rubber ring (or capsule)-sealing fluid sealing technology are briefly analyzed, the advantages and disadvantages of the borehole sealing method and the sealing materials used in coal mines in China are summed up. The results can provides the reference for selection of borehole sealing methods and sealing materials of gas drainage in coal mines.