Pressure-relieving and permeability-increasing method for drilling exploitation of ultra-thin coal seam

Abstract

The invention discloses a pressure-relieving and permeability-increasing method for drilling exploitation of an ultra-thin coal seam. The pressure-relieving and permeability-increasing method for drilling exploitation of the ultra-thin coal seam comprises the following steps that the drilling exploitation position and the thickness of an ultra-thin protective seam are determined, and drilling exploitation parameters such as the drilling exploitation width, the widths of spaced coal pillars and the distances between temporary wide coal pillars are determined; the spaced coal pillars are installed in a spaced mode according to the drilling exploitation width, and when the distance L between the adjacent temporary wide coal pillars is reached, the temporary wide coal pillars are installed; drilling exploitation continues to be conducted till the distance L between the adjacent temporary wide coal pillars is reached again; returning to the temporary wide coal pillar installed before drilling exploitation and backstopping of a goaf is conducted, the temporary wide coal pillar is damaged after backstopping, an upper rock stratum settles, and pressure is relived; and the above steps are executed circularly, a drilling exploitation working surface is continuously advanced till exploitation of the whole working surface is completed. According to the pressure-relieving and permeability-increasing method for drilling exploitation of the ultra-thin coal seam, arrangement of the working surface is simple, equipment is little, and automation is achieved conveniently; accidents such as outburst of gas or water burst under special conditions of a close distance protective seam or a near confined water protective seam are avoided; and working safety is ensured.

Description

technical field [0001] The invention relates to a method for realizing pressure relief of the protected layer by mining a very thin protective layer in mines with high gas or coal and gas outbursts in close coal seam groups. through method. Background technique [0002] The mining of deep coal resources is faced with high gas pressure and high content, and there are dangers of coal and gas outbursts, impact mine pressure and other dynamic disasters in mines. Mining an extremely thin coal seam protection layer with low gas pressure, low content, and low degree of danger first, and releasing the high stress of the upper and lower protected coal seams, and analyzing the low gas permeability coal seam to absorb gas is an effective means for safe and efficient mining of deep coal seam groups. [0003] At present, longwall mining is mainly used for the mining of protective layers. For the case of close-distance coal seam groups with extremely thin coal seam protection layers, du...

AI Technical Summary

Problems solved by technology

For the case of close-distance coal seam groups with extremely thin coal seam protection layers, due to the size limitation of supporting equipment in longwall mining, a large number of tops or bottoms must be broken when mining extremely thin coal seams, which not only increases mining costs, but also reduces coal mining profit margins; At the same time, the working intensity of the staff on the thin working face is high; it also increases the risk of gas outburst or water inrush under special conditions such as close protective layers or adjacent confined water protective layers.

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