Coal underground gasification furnace and gasification method

Abstract

The invention discloses a coal underground gasification furnace and a gasification method. The coal underground gasification furnace comprises a gas inlet hole, a plurality of exhaust holes and a plurality of horizontal directional drilled holes, wherein the gas inlet hole comprises a vertical section and a horizontal section which communicate with each other; the top end of the vertical section is positioned on the ground surface; the horizontal section is positioned in a coal bed; the top ends of the various exhaust holes are positioned on the ground surface while the bottom ends of the exhaust holes are positioned in the coal bed; the horizontal directional drilled holes are in one-to-one correspondence to the various exhaust holes; and two ends of each horizontal directional drilled hole separately communicate with the bottom end of the corresponding exhaust hole and the horizontal section. According to the coal underground gasification furnace and the gasification method, the single long-distance air inlet hole cooperates with the exhaust holes, and thus, the coal extraction quantity of the single hole is increased; and meanwhile, the horizontal directional drilled holes can be short, and a gasification process for mobile gas injection can be controlled favorably.

Description

technical field [0001] The invention relates to coal mining technology, in particular to an underground coal gasification furnace and a gasification method. Background technique [0002] Underground coal gasification technology is a coal mining technology that burns buried coal directly and in a controlled manner, and generates combustible gas through the thermal and chemical effects of coal. In the underground coal gasification technology, it is necessary to open a series of boreholes connecting the surface and the coal seam, such as air intake boreholes for delivering gasification agents (such as air, oxygen, etc.) to the coal seam, and output combustible gases (such as methane, hydrogen, carbon monoxide) gas outlet drill holes, etc., in addition, it is obvious that horizontal drill holes need to be set up in the coal seam to communicate with the inlet drill holes and the gas outlet drill holes. The overall channel system composed of boreholes and boreholes opened in the ...

AI Technical Summary

Problems solved by technology

[0006] The disadvantage of the prior art is that, for these two types of underground gasifiers, the drill hole spacing of the checkerboard gasifier is generally 10-50m, usually about 20m, which makes the number of drill holes of this gasifier too large. The amount of coal produced per unit of drilling is low; the number of vertical drilling holes in the through-type gasifier is much less than that of the checkerboard gasifier, but its directional drilling The length of the hole is long, and the size can generally reach 100-300m. Such a directional drilling is too long, and the movement of the gas injection point during the gas injection process is not convenient enough. It is still necessary to set up multiple vertical holes as auxiliary air intake holes.

Images