Gas extraction hole sealing device based on acid blasting

Abstract

The utility model discloses a gas extraction hole sealing device based on acid liquor blasting. The hole sealing device mainly comprises an extraction pipe, a grouting pipe, a slurry return pipe, a front end plug, a rear end plug, an air bag body, an acid liquor blasting bag, a blocking piece and a pressure sensor. When the device is used, firstly, the front end plug is arranged on an extraction pipe in a sleeving mode and placed into an extraction hole, then the air bag bodies are placed on the upper side and the lower side of a hole sealing area and separated by the blocking pieces, and then the rear end plug is arranged on a grouting pipe and a slurry returning pipe in a sleeving mode and placed into the extraction hole. The acid liquor blasting bag is detonated through the remote controller, acid liquor leaks and reacts with materials in the air bag body to generate a large amount of gas, the air bag expands to press the hole wall, and finally grouting is conducted through the grouting pipe to further improve the hole sealing effect. On one hand, gas expansion is used for hole sealing, on the other hand, slurry is used for hole sealing, the hole sealing leakproofness is enhanced through combination of the gas expansion and the slurry, and the gas extraction efficiency is greatly improved.

Description

Technical Field

[0001] The utility model relates to a gas extraction hole sealing device based on acid blasting, belonging to the technical field of coal mine gas prevention and control. Background Art

[0002] High-gas and gas-outburst mines account for 46% of my country's coal mines. Gas accidents often cause secondary accidents such as roof accidents, water seepage accidents, and fire accidents. The proportion of gas accidents in particularly serious accidents is extremely high. There are various gas disaster management technologies, but most of them require drilling holes into the coal seams to extract gas. Therefore, the airtightness of the boreholes will inevitably affect the effect of gas extraction. However, due to the soft coal seams in my country, the airtightness of the boreholes deteriorates in the later stages of extraction, which greatly restricts the effect of gas extraction.

[0003] In addition, my country's coal mines lack management of borehole tightness, which leads to a rapid decline in gas extraction flow and a continuous decline in gas extraction efficiency. Therefore, it is necessary to study new sealing devices or technologies to improve the gas control effect, which has become an urgent problem to be solved in coal and gas outburst mines.

[0004] The existing acid detonation seal adopts the liquid injection method, such as a pressure sealing device and use of acid disturbance for coal mines (patent number 201910956942.X). This device has high protection requirements for the management and use of acid and requires additional protection measures. It is not suitable for widespread use underground. Summary of the invention

[0005] In order to address the deficiencies in the prior art, the utility model provides a gas extraction hole sealing device based on acid blasting, which can achieve good support for the gas extraction borehole, improve the airtightness of the sealing hole, and solve the problem of high operating protection requirements brought about by the acid injection method.

[0006] To achieve the above purpose, the technical solution adopted by the utility model is: a gas extraction hole sealing device based on acid blasting, including an extraction pipe, a grouting pipe, and a return grouting pipe, the extraction pipe, the grouting pipe, and the return grouting pipe are fixed together by fixing parts to form an extraction combined pipe body, and the front ends of the extraction pipe, the grouting pipe, and the return grouting pipe are staggered.

[0007] It is characterized by: it also includes a front end plug, a rear end plug, an air bag and an acid blasting bag.

[0008] The front end plug and the rear end plug are fixed at the front end of the extraction combined pipe body at a distance, and the front end of the extraction pipe is located at the front end of the front end plug, and the front ends of the grouting pipe and the return grouting pipe are located between the front end plug and the rear end plug;

[0009] A baffle plate is provided between the front end plug and the rear end plug to surround the front ports of the grouting pipe and the return grouting pipe. An airbag body is provided in the annular space formed by the baffle plate, the front end plug and the rear end plug. The airbag body is filled with acid liquid. An acid blasting bag is provided in the acid liquid. The acid blasting bag is connected to the bag lifting device through a wire passing through the seal of the airbag body and the rear end plug.

[0010] According to the gas extraction hole sealing device based on acid blasting, the device is placed in the coal seam gas extraction borehole, and the front end plug and the rear end plug are circular structures. When placed in the coal seam gas extraction borehole, the front end plug and the rear end plug are in contact with the peripheral surface of the extraction borehole.

[0011] According to the gas extraction hole sealing device based on acid blasting, a pressure sensor is also provided, which is arranged in the airbag body. The circular circumferential outer baffles of the front end plug and the rear end plug, the outer baffles and the baffle plates and the front end plug and the rear end plug form a fixed space to install the airbag body.

[0012] According to the gas extraction hole sealing device based on acid blasting, there are multiple airbags divided by isolation plates.

[0013] The utility model is a gas extraction hole sealing device based on acid blasting, which strictly follows the scheme of "two blocking and one injection" to seal the extraction hole for complete protection of gas extraction, improves the injection form of the acid solution, and improves the operating efficiency;

[0014] Compared with the existing acid injection method, it does not require special acid equipment and protective equipment, reduces the complexity of operation, achieves effective support for gas extraction drilling holes, and has good sealing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the utility model,

[0016] Figure 2 This is a cross-sectional view of the utility model.

[0017] In the figure: 1, coal seam, 2, extraction hole, 3, extraction pipe, 4, grouting pipe, 5, return slurry pipe, 6, front end plug, 7, rear end plug, 8, air bag body, 9, acid blasting bag, 10, baffle, 11, pressure sensor, 12 outer baffle, 13 isolation plate. DETAILED DESCRIPTION

[0018] The specific structure of the utility model is further described below:

[0019] The utility model discloses a gas extraction hole sealing device based on acid blasting, comprising an extraction pipe 3, a grouting pipe 4, and a return grouting pipe 5, wherein the extraction pipe 3, the grouting pipe 4, and the return grouting pipe 5 are fixed together by fixing parts to form an extraction combined pipe body, wherein the front ends of the extraction pipe 3, the grouting pipe 4, and the return grouting pipe 5 are arranged in a staggered manner, and further comprising a front end plug 6, a rear end plug 7, an air bag body 8, and an acid blasting bag 9, wherein the front end plug and the rear end plug 7 are fixed at the front end of the extraction combined pipe body at a distance, and the front end of the extraction pipe 3 is located at the front end of the front end plug, and the front ends of the grouting pipe 4 and the return grouting pipe 5 are located between the front end plug 6 and the rear end plug 7; a baffle 10 is also arranged between the front end plug 6 and the rear end plug 7 to surround the front ends of the grouting pipe 4 and the return grouting pipe 5, and an annular space formed by the baffle 10, the front end plug 6, and the rear end plug 7 is provided with an air bag body 8, and the air bag body 8 The inside is filled with acid liquid, in which an acid liquid blasting bag 9 is arranged. The acid liquid blasting bag 9 is connected to the bag-lifting device through a wire passing through the sealing opening of the airbag body 8 and the rear end plug 7.

[0020] According to the gas extraction hole sealing device based on acid blasting, the device is placed in the coal seam gas extraction borehole, and the front end plug 6 and the rear end plug 7 are circular structures. When placed in the coal seam gas extraction borehole, the front end plug 6 and the rear end plug 7 are in contact with the peripheral surface of the extraction borehole.

[0021] A pressure sensor 11 is also provided, which is arranged in the airbag body 8. The circular circumferential outer baffle of the front end plug 6 and the rear end plug 7, the outer baffle and the baffle sheet and the front end plug 6 and the rear end plug 7 form a fixed space to install the airbag body 8.

[0022] According to the gas extraction hole sealing device based on acid blasting, there are multiple airbags divided by isolation plates.

[0023] The material inside the airbag can be sodium carbonate or calcium carbonate. As a further solution of the utility model: the acid blasting bag includes a detonating bag and acid, and the concentration of the acid is set to 15%. All pipelines and components of this device need to be treated to prevent acid corrosion. The detonating bag is a conventional detonator structure, and the outside is wrapped with sealing materials to isolate the acid.

[0024] The method of use comprises the following steps:

[0025] First, drill a drainage hole in the coal seam, and put the front end plug on the drainage pipe and put it into the drainage hole;

[0026] Place the airbag body on the upper and lower sides of the sealing area, then put in the baffle and fix the airbag body; put the rear end plug on the grouting pipe and the return grouting pipe and put them into the extraction hole;

[0027] After all the equipment is connected and placed, the acid blasting bag is detonated by remote control. The acid leaks and reacts with the material in the airbag to generate a large amount of gas, causing the airbag to expand and compress the hole wall;

[0028] Finally, start the grouting pump to inject grout through the grouting pipe to further improve the airtightness of the borehole. Stop grouting when slurry flows out of the return pipe.

[0029] The pressure sensor monitors the sealing pressure of the device in real time. When the reading of the pressure sensor receiving device is lower than 4 Pa, the above steps are repeated to detonate other airbags. The airbags release carbon dioxide to form a high-pressure space, which is then grouting and sealing again.

[0030] The utility model realizes a novel gas extraction drilling hole sealing method, and gas extraction is performed through an extraction pipe according to a conventional method.

Claims

1. A gas extraction hole sealing device based on acid blasting, comprising an extraction pipe (3), a grouting pipe (4), and a return grouting pipe (5), wherein the extraction pipe (3), the grouting pipe (4), and the return grouting pipe (5) are fixed together by a fixing member to form an extraction combined pipe body, and the front ends of the extraction pipe (3), the grouting pipe (4), and the return grouting pipe (5) are staggered. Features: It also includes a front end plug (6), a rear end plug (7), an air bag body (8) and an acid blasting bag (9). The front end plug and the rear end plug (7) are fixed at a distance at the front end of the extraction combined pipe body, and the front end of the extraction pipe (3) is located at the front end of the front end plug, and the front ends of the grouting pipe (4) and the return grouting pipe (5) are located between the front end plug (6) and the rear end plug (7); A baffle (10) is provided between the front end plug (6) and the rear end plug (7) to surround the front ends of the grouting pipe (4) and the return grouting pipe (5). An air bag (8) is provided in the annular space formed by the baffle (10), the front end plug (6) and the rear end plug (7). The air bag (8) is filled with sodium carbonate or calcium carbonate. An acid blasting bag (9) is provided in the acid. The acid blasting bag (9) is connected to the bag lifting device through a wire passing through the sealed opening of the air bag (8) and the rear end plug (7).

2. The gas extraction hole sealing device based on acid blasting according to claim 1 is characterized in that: The device is placed in a coal seam gas extraction borehole. The front end plug (6) and the rear end plug (7) are circular structures. When placed in the coal seam gas extraction borehole, the front end plug (6) and the rear end plug (7) are in contact with the peripheral surface of the extraction borehole.

3. The gas extraction hole sealing device based on acid blasting according to claim 1 is characterized in that: A pressure sensor (11) is also provided. The pressure sensor (11) is arranged in the airbag body (8). The circular peripheral outer baffles of the front end plug (6) and the rear end plug (7) form a fixed space for installing the airbag body (8) with the outer baffle plate, the baffle plate, the front end plug (6), and the rear end plug (7).

4. The gas extraction hole sealing device based on acid blasting according to claim 1 is characterized in that: The airbags are multiple and divided by partition plates.

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