Coal bed underground gasifying method

Abstract

The invention relates to a coal bed underground gasifying method. The coal bed underground gasifying method comprises the following steps of establishing a gasifying tunnel in a to-be-gasified coal bed; arranging a plurality of blasting devices in the to-be-gasified coal bed, wherein the blasting devices are arranged corresponding to a plurality of coal bed sections of the to-be-gasified coal bed; igniting or striking a fire in the gasifying tunnel to start the gasifying process; utilizing a flame movement heating method to gradually blast the blasting devices, so as to loosen the coal bed sections before the corresponding coal bed section is gasified. The coal bed underground gasifying method has the advantages that the blasting devices are pre-arranged in the to-be-gasified coal bed, so while cracks in the coal bed are increased by blasting, and the gasifying is also performed; before the gasifying of each coal bed section, the looseness of the corresponding coal bed section is completed, and the gasifying efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of coal seam gasification, in particular to an underground coal seam gasification method. Background technique [0002] Underground coal gasification is carried out in the coal seam in the gasification channel. Its core technology is to make the gasification agent (air or oxygen, water vapor, etc.) fully contact with the underground coal seam, and through the pyrolysis and chemical action of coal, produce flammable gas. Therefore, the depth of the gasification reaction is an extremely important parameter, especially for diagenetic coals such as anthracite, lean coal, and lean coal, and coals with a high degree of carbonization, which sometimes only occur on the surface of the coal wall, which is not conducive to the gasification of underground coal mining. use. [0003] During the gasification process, the coal seam fracture rate (the degree of development of bedding, joints and fissures) directly affects ...

AI Technical Summary

Problems solved by technology

However, the coal seam gap increase in the prior art can only expand the original coal seam cracks through high-pressure gas, because the operating pressure in the normal gasification stage is far lower than the pressure in the gap increase stage, so when turning from the gap increase stage to gasification After the gasification stage, the operating pressure will be greatly reduced, and the coal seam fissures that have been opened in the original coal seam will gradually close as the pressure decreases. The real impact on the gasification stage is very small, and it can only play a certain role in the ignition of the gap increase stage. effect

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