A Coal Seam Permeability Enhancement Method Cooperating with Electric Pulse and Coal Seam Water Injection

Abstract

Disclosed is a coal seam antireflection method through synergy of an electric pulse and coal seam water injection. The method is suitable for improving the extraction rate of a coal seam in a low airpermeable and high gassy area. The method comprises the steps that firstly, negative electrode drilling and positive electrode drilling are conducted in the coal seam, then high-pressure rubber hosesare sent to the middles of boreholes, after the borehole is sealed and closed, ionic water of a certain pressure is injected into the coal seam, constant pressure is maintained for 20-30 days, and theion water in the borehole is discharged through a drainage system; a positive electrode and a negative electrode are sent to the middle of the coal seam, the positive electrode and the negative electrode are in contact with the coal wall, then the coal seam is discharged through an explosion-proof high-pressure control table and a high-voltage discharge switch, and the coal seam is disrupted; andthe positive electrode and negative electrode are taken out, the negative electrode borehole and the positive electrode borehole are connected into a gas extraction pipeline. According to the coal seam antireflection method through synergy of the electric pulse and coal seam water injection, the conductivity of a coal body is enhanced by injecting the ionic water into the coal seam, then energy produced from the high-voltage electric pulse directly acts on the coal body to make the coal body produce a large number of fractures, and the gas extraction rate of a single hole can be effectively increased.

Description

technical field [0001] The invention relates to a coal seam anti-permeability method, in particular to a coal seam anti-permeability method in which electric pulses and coal seam water injection are coordinated to improve the coal seam extraction rate in low-permeability and high-gas areas. Background technique [0002] In recent years, as my country's coal mines enter the deep mining stage, the problems of low gas permeability and high gas content in coal seams are particularly prominent, and the key to solving this problem is to improve the gas permeability of coal seams. At present, the commonly used methods to increase the air permeability of coal seams include: mining the liberated seam, hydraulic fracturing, deep hole blasting, etc., but these technologies themselves also have great defects: mining the liberated seam will have a lot of gangue and it is not suitable for Single coal seam mining; the direction of hydraulic fracturing is difficult to control and will waste...

AI Technical Summary

Problems solved by technology

At present, the commonly used methods to increase the air permeability of coal seams include: mining the liberated seam, hydraulic fracturing, deep hole blasting, etc., but these technologies themselves also have great defects: mining the liberated seam will have a lot of gangue and it is not suitable for Single coal seam mining; the direction of hydraulic fracturing is difficult to control and will waste a lot of water resources, and the crack expansion range is small; deep hole blasting technology is difficult to transport explosives to the preset location in soft coal seams

Based on the shortcomings of the existing coal seam anti-permeability technology, it is particularly important to develop a simpler and more effective coal seam anti-permeability method to solve the problem of difficult gas drainage in low-permeability coal seams

Images