Plasma H-type method for reducing thick and hard roof and residual coal pillar composite strong ore pressure

Abstract

The invention discloses a plasma H-type method for reducing thick and hard roof and residual coal pillar composite strong ore pressure and belongs to the field of coal mining. According to the method,the characteristic that high temperature and high pressure are generated instantly due to strong movement between plasmas is fully utilized, an H type borehole is drilled in the ground over a residual mining area residual coal pillar, and is divided into an H type borehole left vertical segment, an H type borehole horizontal segment and an H type borehole right vertical segment; the H type borehole left and right vertical segments penetrate through an overlying coal layer thick and hard roof and an overlying coal layer to reach into an underlying residual mining area residual coal pillar; theH type borehole horizontal segment is parallel with the work face propelling direction in the overlying coal layer thick and hard roof; one well achieves dual purposes, and two-way operation is achieved; and pre-cracking is performed on the overlying coal layer thick and hard roof and the underlying residual mining area residual coal pillar, the purpose of reducing the thick and hard roof and residual mining area residual coal pillar composite strong ore pressure is achieved, and therefore green mining of the coal mine is achieved, and safe production is achieved.

Description

technical field [0001] The invention relates to a plasma H-type method for reducing the composite strong mine pressure of a thick hard roof and a leftover coal pillar, which belongs to the field of coal mining. Background technique [0002] Upward mining method, that is, the underlying coal seam is mined first and then the overlying coal seam is mined. When the overlying coal seam is mined, it will pass through the thick and hard roof between the layers and the remaining coal pillars in the underlying residual mining area, and the coal mining work will be affected by the upper and lower composite strong mine pressure. [0003] Composite strong rock pressure mainly comes from: (a) thick and hard roof: Due to natural geological conditions, the overlying coal seams in many mining areas have thick and hard roofs with large thickness, high strength, no joints and fissures, and good integrity; (b) residual Remaining coal pillars in the mining area: In the early days of the foundin...

AI Technical Summary

Problems solved by technology

However, the technology of reducing composite strong mine pressure by plasma is rarely applied in the field of coal mining technology (especially in the field of "H-type" plasma surface reduction of thick hard roof and residual coal pillars in residual mining area).

Images