Secondary grouting and plugging device and method of regional crack field of gas extraction and drilling group

Abstract

The invention provides a secondary grouting and plugging device and method of a regional crack field of a gas extraction and drilling group, which are particularly suitable for plugging cracks of a coal mine penetrating layer and a through network of an easily-crushed coal rock body region which is close to a coal layer gas extraction and drilling group. The device comprises a mortar filling pipe, a sticky solution filling pipe, a front baffle, a rear baffle and an elastic capsule with a needled micro-pore; the secondary grouting and plugging method of the regional crack field of the gas extraction and drilling group comprises the following steps of: drilling a sticky solution filling drilled hole; inserting a regional crack curtain type grouting and plugging device of an underground coal mine gas extraction and drilling group into the sticky solution filling drilled hole; filling cement mortar; filling a sticky liquid after the cement mortar is condensed; and permeating the pressurized sticky liquid into the network cracks on the periphery of the drilling group to realize the effective plugging of in-situ and secondary network cracks in a regional coal rock body. The structure is simple, and the method is convenient to operate and is safe and reliable.

Description

technical field [0001] The invention relates to a secondary grouting sealing device and method for the regional fissure field of a gas drainage drilling group, and is especially suitable for the regional penetration of easily broken coal and rock masses near the gas drainage drilling group in coal mines. Closing of network gaps. Background technique [0002] As an associated product of coal, gas is not only the source of major gas disasters in coal mines, but also a valuable non-renewable energy source. With the increase of coal mining depth, the gas content of coal seams will increase significantly. Realizing coal and gas co-mining is an inevitable way to mine deep coal resources. At the same time, it is of great significance to improve the safe and efficient production level of coal mines and reduce greenhouse gas emissions. . [0003] At present, the pre-drainage of coal seam gas is the basic measure to realize the joint mining of coal and gas and reduce gas accidents, ...

AI Technical Summary

Problems solved by technology

Up to now, most of the sealing materials for gas drainage boreholes are cement mortar, polyurethane and other sealing materials, but it is difficult for cement mortar or polyurethane materials to penetrate into the network cracks of broken coal and rock mass to achieve effective sealing.

At the same time, with the prolongation of the gas extraction time and the impact of coal seam mining, the cracks in the coal and rock mass are constantly developing and expanding, and the interconnected network cracks can easily lead to the leakage of outside air into the extraction pipeline. As a result, the concentration of gas drainage and the effective negative pressure of drainage are reduced, the validity period of gas drainage is shortened, and the effective utilization rate of gas drainage drilling is also reduced.

[0004] In addition, under the action of extraction negative pressure, the leakage of air through network cracks can easily cause fire accidents in extraction boreholes, seriously affecting the safety of coal mines and gas extraction systems

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