Wire saw cutting device and coal seam gas permeability-increasing pressure-relieving method

Abstract

The invention discloses a wire saw cutting device and a coal seam gas permeability-increasing pressure-relieving method, and relates to the field of coal seam gas pressure relieving. The device comprises a wire saw machine and an adjusting piece. The method comprises the steps that S1, the effective drainage radius after slotting of the wire saw machine is determined; S2, the drilling density andposition are determined according to the effective drainage radius, and drilling is conducted; and S3, the whole coal seam is subjected to cutting slotting through the wire saw machine. According to the device and the method, a large free space is formed in a coal body through whole-face cutting of a coal seam, surrounding coal bodies move, deform and generate flowing deformation in the directionof the free space, the stress balance of the coal body is continuously and repeatedly broken, and finally, the coal body is in a new balance state; when the coal body is cut, a new crack is formed inthe coal body, the new crack and a primary crack and a free space pore system expand, intersect and communicate, and the gas permeability of the coal body is improved; and after slotting, a space is provided for expansion deformation of the surrounding coal bodies, the expansion deformation causes expansion and mutual penetration of pore and crack systems in the coal body, favorable conditions areprovided for efficient desorption and high-speed flowing of gas, the original property of the coal body is changed, and the outburst risk of a coal seam area is quickly eliminated.

Description

technical field [0001] The invention relates to the field of coal seam gas pressure relief, in particular to a wire saw cutting device and a coal seam gas permeability enhancement and pressure relief method. Background technique [0002] In recent years, with the increasing demand for coal due to economic development, the strength and intensity of mine mining have increased, so that most of the existing mines in our country have entered the deep mining stage. The increase of buried depth of coal seam increases the ground stress of the mine, the air permeability of coal seam and surrounding rock becomes poor, and the distance of gas displacement to the surface increases. , Coal seams are more likely to be unstable under high stress and other factors have caused dynamic phenomena to appear in some mines and coal seams that were not previously in danger of outburst. The use of mining protection layers, pre-pumping coal seam gas and other means can effectively release the in-situ...

AI Technical Summary

Problems solved by technology

The increase of coal seam buried depth increases the stress of the mine, the gas permeability of the coal seam and surrounding rock becomes poor, and the distance of gas displacement to the surface increases. , Coal seams are more likely to be unstable under high stress and other factors have caused dynamic phenomena to appear in some mines and coal seams that were not previously in danger of outbursts. The use of mining protection layers, pre-pumping coal seam gas and other means can effectively release the in-situ stress and gas potential in coal seams, and change Due to the original nature of the coal body, most of the outburst dangerous coal seams in my country have the characteristics of low air permeability and easy rheology, and many mines have no protective layer to mine or there are areas that cannot be protected. The conventional technology has a large amount of engineering and the effect of drainage is not good. First, and the interoperability is not strong; the amount of gas drainage is unstable, the time is long, and the operation is complicated, which will eventually lead to problems such as high drainage costs or incomplete disaster control and lag

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