Broaching method of coal seam channel

Abstract

The invention aims to provide a broaching method of a coal seam channel. The coal seam channel can be rapidly broached in the broaching method. The broaching method comprises the steps that a, high-energy inflammable material is laid in the coal seam channel; b, combustion improver is injected into the coal seam channel and the high-energy inflammable material is ignited; c, the combustion improver continues to be injected. Due to the facts that the high-energy inflammable material is laid in the coal seam channel and the combustion improver continues to be injected, part of aflame high-energy inflammable material rapidly ignites another part of the high-energy inflammable material adjacent to the part of aflame high-energy inflammable material along the laying route of the high-energy inflammable material in the coal seam channel, simultaneous combustion of the high-energy inflammable material laid in the coal seam channel can be formed, and therefore temperature of the area, where the high-energy inflammable material is laid, in the coal seam channel is rapidly and evenly increased, coal seams in the area are ignited simultaneously, simultaneous combustion of the coal seams in the area is achieved, and broaching speed of the coal seam channel is increased. In addition, the phenomena that combustion of the coal seam channel deviates from the established coal seam channel, and hole diameters of the coal seam channel are different after broaching can be avoided.

Description

technical field [0001] The invention relates to the field of mineral gasification, in particular to a hole-enlarging method for coal seam passages. Background technique [0002] Underground coal gasification usually establishes at least one inlet channel and at least one gas outlet channel from the ground to the underground coal seam, and then establishes a gasification channel in the coal seam to connect the above-mentioned inlet channel and gas outlet channel, and then passes the inlet channel to the gasification channel. Gasification agent (oxygen-containing gas) is injected into the channel to ignite the coal seam to start gasification, and the gas produced by gasification is discharged from the gas outlet channel. [0003] Generally, the coal seam channel for underground coal gasification (referred to as the coal seam channel) is not very large in diameter (<300mm). Previously, coal seam passages were reamed by methods such as reaming with reaming drills, fire reami...

AI Technical Summary

Problems solved by technology

[0006] Although the methods in CN201110388215.1 and CN200810119354.2 can expand the aperture of the gasification channel, but because the gasification channel is long and the coal seam combustion speed is slow, the aperture speed of the expansion gasification channel is too slow by the above method

In addition, there are large cracks or thick gangue layers in the coal seam, and the combustion may deviate from the established gasification channel, and may also cause the pore size of the expanded gasification channel to be uneven

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