Hole Reaming Method for Coal Seam Passage

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 method for expanding a hole of a coal seam channel. Background technique [0002] Underground coal gasification is usually by establishing at least one air inlet channel and at least one gas outlet channel from the ground to the underground coal seam, and then establishing a gasification channel in the coal seam to connect the above air inlet channel and gas outlet channel, and then through the air inlet channel to the gasification channel. The gasification agent (oxygen-containing gas) is injected into the channel, the coal seam is ignited, and gasification starts, and the gas produced by gasification is discharged from the gas outlet channel. [0003] Usually, the diameter of the coal seam channel (coal seam channel for short) for UCG is not very large (<300mm). The coal seam channel will be reamed before, and the methods include: reaming with reaming tools, thermal co...

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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