Directional hydraulic centralized exploding device for improving gas permeability of coal seam

Abstract

The invention discloses a directional hydraulic centralized exploding device for improving the gas permeability of a coal seam, and relates to the technical field of coal seam permeability improvement. The directional hydraulic centralized exploding device for improving the gas permeability of the coal seam comprises a directional exploding tube, wherein the two ends of the directional exploding tube are sealed by cover plates; a plurality of energy release holes are formed in the outer circumferential surface of the directional exploding tube at intervals; the energy release holes are communicated with the inner cavity of the directional exploding tube; the inner cavity of the directional exploding tube is filled with explosive rolls and detonators; the outer circumferential surface of the directional exploding tube is coated with a high-pressure plastic thin film; the energy release holes are covered by the high-pressure plastic thin film; the top end of the directional exploding tube is connected with a first plugging assembly for plugging a blast hole during explosion so as to prevent explosion fragments from being upwardly ejected along the blast hole. Through coupling of explosion gas and water which is left in the blast hole and the coal seam after a hydraulic fracturing operation, the directional hydraulic centralized exploding device can greatly improve the development degree of a fracture in the coal seam; in addition, the blast hole of the directional hydraulic centralized exploding device is not required to be filled with a yellow clay roll before explosion, so that the directional hydraulic centralized exploding device is very convenient to operate.

Description

technical field [0001] The invention relates to the technical field of coal seam anti-permeability, in particular to a directional water pressure centralized blasting device for improving the air permeability of coal seams. Background technique [0002] More than half of the existing coal mines are high gas and coal and gas outburst mines. Gas generally exists in coal seams in two forms, that is, adsorption state and free state. In the amount of gas stored in coal seams, the amount of adsorbed gas usually accounts for more than 90%, while the amount of free gas is only about 10%. When the coal seam is mined, the gas trapped in the coal seam is continuously released with the disturbance of the coal seam mining, and its hazards are mainly manifested in three aspects: gas suffocation, gas explosion, and coal and gas outburst. According to statistics, more than 40% of coal mine accidents in my country are gas explosion accidents, among which gas explosion accidents account for...

AI Technical Summary

Problems solved by technology

But, in actual application, the blasting device that this method adopts also has the following defects: 1. In order to avoid a large amount of explosion fragments from spraying upwards along the blasthole, it needs to be blocked with yellow mud rolls within the range of 10m away from the orifice. The workload of filling the yellow mud rolls into the blast holes is relatively large

2. The blasting device can only be placed at the bottom of the blast hole. For thicker coal seams (for example, 10m thick), the effect of bottom blasting on the top of the coal seam is very limited.

3. The amount of water in the water bag is small, and the "spike effect" formed by the coupling of water and explosive gas is limited, and the effect still needs to be improved

Images