Method for intensifying coal seam gas extraction through two-way long-distance directional drilling overlapping

Abstract

The invention relates to a method for intensifying coal seam gas extraction through two-way long-distance directional drilling overlapping, and belongs to the field of coal mine safety. A stope face is divided into an early-stage mining part, a middle-stage mining part and a later-stage mining part according to the mining replacement plan of the stope face and the coal seam gas occurrence condition; long-distance directional drilling holes are constructed in the coal body of the stope face from an air return main roadway of a panel where the stope face is located to the coal body of the stope face in the trend direction of the coal body of the stope face; long-distance directional drill holes are constructed in a coal body of the stope face from an air return main roadway of an adjacent panel, the two-way long-distance directional drill holes of an early-stage mining part have an overlapping area, one side of the overlapping area exceeds the cutting hole of the stope face in the advancing direction, and the other side of the overlapping area is located behind the cutting hole of the stope face; the two-way long-distance directional drill hole of the middle-stage mining part has an overlapping area, and the overlapping area is in a gas content enrichment area in the coal body; the two-way long-distance directional drill holes of the later mining part have no overlapping area.

Description

technical field [0001] The invention belongs to the field of coal mine safety, and relates to a method for overlapping and strengthening coal seam gas extraction with bidirectional long-distance directional drilling. Background technique [0002] Gas is one of the main threats to mine safety production. It is a combustible gas with methane as the main component, which occurs in coal seams or surrounding rocks in the form of adsorption and dissociation. When the gas concentration in a coal mine is within a certain range, a gas explosion can occur in the presence of an open flame or other fire source, thereby destroying the underground equipment or causing mass death and injury to operators. Therefore, gas drainage must be implemented in high gas, coal and gas outburst mines to reduce the gas content of coal seams and achieve the purpose of disaster prevention and mitigation. Gas drainage is to use drilling equipment to construct a hole in the coal seam, and then seal the hol...

AI Technical Summary

Problems solved by technology

However, it cannot be ignored that, with the mining of many advanced scientific production mines, their work is shifting to the deep area, the gas content and pressure are gradually increasing, the problem of gas control is becoming more and more prominent, and the length of the mining face generally exceeds 3000m. The intensive short-hole drainage can no longer meet the needs of high-yield, high-efficiency and safe mining in high-gas mines.

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