Method and device for upward cracking left coal pillars in residual mining area through microwave heating

Abstract

The invention discloses a method and device for upward cracking left coal pillars in a residual mining area through microwave heating, and belongs to the field of coal mining. According to the methodand the device, in a stress relaxed area below the left coal pillars in the residual mining area, two drilling holes are drilled in each left coal pillar in the residual mining area in top rock of a haulage gate and an air return way 15-25 meters away from the working face end, and the left coal pillars in the residual mining area are cracked. The characteristics of microwave heating that the efficiency is high, energy density is high, no medium is needed for heat transmission, and penetrability is high are sufficiently utilized, and when a working face of an underlie coal seam is mined to theposition near the left coal pillars of the residual mining area, upward cracking is conducted on the left coal pillars in the residual mining areas from the underlie coal seam. According to the method for upward cracking the left coal pillars in the residual mining area through microwave heating, the efficiency is high, control is easy, the effect is good, the flexibility is high, the integrity of the coal pillars is reduced, the purposes of weakening strength, releasing stress and relieving strata behaviors are achieved, and the safety of roof control is greatly improved.

Description

technical field [0001] The invention relates to a method and a device for microwave heating of coal pillars left in an upward fracturing residual mining area, belonging to the field of coal mining. Background technique [0002] In the early days of the founding of New China, my country's coal mining technology was relatively backward. In order to ensure the stability of the surrounding rock and ensure the safe production of the working face, some coal pillars were left to support the overlying strata; in the modern highly mechanized mining process, affected by the structure and Due to the limitation of other mining conditions, it is inevitable to leave some coal pillars; when adopting the pillar system coal mining method, some coal pillars will be left unmined. This has just resulted in a large number of remaining coal pillars in the residual mining area after the coal seam has been mined. [0003] When the downward mining method is used in coal mines in my country, the unde...

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Problems solved by technology

However, microwave heating and fracturing technology is rarely applied in the field of coal mining technology.

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