Carbon dioxide fracturing for treating gas based on gas digesting agent and construction method of carbon dioxide fracturing

Abstract

The invention relates to the related technical field of gas treatment, in particular to a carbon dioxide fracturing device for gas treatment based on a gas digesting agent and a construction method thereof.The carbon dioxide fracturing device comprises a coal seam, a first drill hole is formed in the inner side surface of the coal seam, a galvanized pipe is connected to the inner side surface of the first drill hole, and a fracturing mechanism is arranged at one end of a through cable drill rod; and a grouting mechanism is arranged at one end of the grouting pipe. According to the carbon dioxide fracturing for treating the gas based on the gas digesting agent and the construction method of the carbon dioxide fracturing for treating the gas based on the gas digesting agent, the fracturing mechanism and the grouting mechanism are arranged, a fracturing pipe, a galvanized pipe and the like are connected into a fracturing drill hole, water injection and hole sealing preparation is made, corresponding equipment is placed in a liquid injection and extraction hole, after a gas extraction test is conducted, fracturing blasting is conducted, and then the drill hole is blocked; the method comprises the following steps of: injecting a specific drill hole into a coal mine, then performing subsequent gas extraction and observation, injecting a fire preventing and extinguishing material into the specific drill hole, and finally monitoring gas extraction parameters, so that all links are tightly matched to realize an efficient and safe coal mine operation environment.

Description

Technical Field

[0001] The present invention relates to the technical field related to gas treatment, and in particular to carbon dioxide fracturing for treating gas based on a gas digester and a construction method thereof. Background Art

[0002] In underground mining fields such as coal mines, safe production is a vital lifeline. However, the existence of gas is like a "bomb" that may explode at any time, posing a great safety threat to the underground working environment. With the continuous increase in the depth and intensity of coal mining, the importance and urgency of gas control are becoming increasingly prominent. The main component of gas is methane, which is a colorless, tasteless, and odorless combustible gas. During coal mining, gas will continue to gush out from the coal seam. When the concentration of gas in the air reaches a certain range, it will cause an explosion when it encounters a fire source. Its explosion is so powerful that it will not only destroy underground equipment and tunnels, but also cause serious casualties. In addition, high concentrations of gas can also cause suffocation of personnel, posing a direct threat to the life safety of miners. Traditional gas control methods have great limitations. The coal mining industry urgently needs an innovative and efficient gas control technology. With the continuous advancement of science and technology, the emergence of new technical means such as carbon dioxide fracturing technology and gas digesters has brought new hope and opportunities for gas control. Therefore, there is a special need for carbon dioxide fracturing and its construction method based on gas digesters to control gas.

[0003] The existing carbon dioxide fracturing technology has gradually attracted attention. However, its application field in conjunction with gas digesters for gas control has not been fully and deeply explored. Therefore, it is necessary to provide a carbon dioxide fracturing based on gas digesters for gas control and a construction method thereof that is both efficient and safe, in order to make up for the defects of the existing gas control technology. Summary of the invention

[0004] The purpose of the present invention is to provide a carbon dioxide fracturing for gas control based on a gas digester and a construction method thereof, so as to solve the problem that the existing carbon dioxide fracturing technology proposed in the above background technology has gradually attracted attention, but its application field in conjunction with a gas digester for gas control has not been fully and deeply explored. Therefore, it is necessary to provide a carbon dioxide fracturing for gas control based on a gas digester and a construction method thereof that is both efficient and safe, so as to make up for the defects of the existing gas control technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: gas-based carbon dioxide fracturing for gas treatment using a gas digester and a construction method thereof, comprising a coal seam, wherein a No. 1 borehole is opened on the inner surface of the coal seam, a No. 2 borehole is opened on the inner surface of the coal seam, a No. 3 borehole is opened on the inner surface of the coal seam, a No. 4 borehole is opened on the inner surface of the coal seam, a galvanized pipe is connected to the inner surface of the No. 1 borehole, a water injection hole sealer is slidably connected to the inner surface of the No. 1 borehole, and one end of the water injection hole sealer is fixedly connected to the inner surface of the No. 1 borehole. There is a cable drill rod, one end of which is provided with a fracturing mechanism, the other end of the water injection hole sealer is connected to a water injection pipe, one end of the water injection pipe is fixedly connected to a first pressure gauge, one side surface of the first pressure gauge is fixedly connected to a hand pump, the lower surface of the hand pump is fixedly connected to a base, the inner surface of the No. 2 borehole is connected to a mining hole sealer, the inner surface of the No. 2 borehole is connected to a bag-type hole sealer, one end of the bag-type hole sealer is connected to a grouting pipe, and one end of the grouting pipe is provided with a grouting mechanism;

[0006] The fracturing mechanism includes a detonating head, a heating tube, a main pipe, a gasket, an energy dissipation sheet and an energy dissipation head. One end of the cable drill pipe is connected to the detonating head, one side surface of the detonating head is fixedly connected to the heating tube, one side surface of the detonating head is threadedly connected to the main pipe, one side surface of the main pipe is slidably connected to the gasket, one side surface of the main pipe is slidably connected to the energy dissipation sheet, and one side surface of the main pipe is threadedly connected to the energy dissipation head.

[0007] Preferably, the No. 1 borehole corresponds to the No. 4 borehole, which is a construction fracturing borehole with a borehole diameter of 94 mm.

[0008] Preferably, the No. 2 borehole corresponds to the No. 3 borehole, which is an injection hole and a extraction hole, and the borehole diameter is 94 mm.

[0009] Preferably, the size of the galvanized pipe is 20 mm, and multiple groups are arranged in the drilled hole.

[0010] Preferably, a plurality of main pipes are arranged inside borehole No. 1, and the interior of the main pipes can be filled with liquid carbon dioxide.

[0011] Preferably, two groups of gaskets are provided, and the material of the gaskets is a composite material of rubber and metal.

[0012] Preferably, the grouting mechanism includes a grouting head, an air pump, a second pressure gauge, a grouting pipe, a bracket, a motor plate, a drive motor, a motor shaft, a stirring blade and a stirring barrel, one end of the grouting pipe is fixedly connected to the grouting head, one end of the grouting head is fixedly connected to the air pump, one side surface of the air pump is fixedly connected to the second pressure gauge, the lower surface of the air pump is fixedly connected to the grouting pipe, the lower surface of the air pump is fixedly connected to the bracket, the upper surface of the bracket is fixedly connected to the motor plate, the upper surface of the motor plate is fixedly connected to the drive motor, the lower surface of the drive motor is fixedly connected to the motor shaft, the outer surface of the motor shaft is fixedly connected to the stirring blade, and the lower surface of the bracket is fixedly connected to the stirring barrel.

[0013] Preferably, the motor shaft passes through the motor plate and is rotationally connected to the motor plate, and a plurality of stirring blades are arranged on the surface of the motor shaft.

[0014] Preferably, a filter screen is provided inside the grouting head, and the grouting pipe is made of corrosion-resistant rubber or plastic material.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: the carbon dioxide fracturing based on gas digester for gas treatment and the construction method thereof, through the arrangement of No. 1 drilling hole, No. 2 drilling hole, No. 3 drilling hole, fracturing mechanism, grouting mechanism, etc., when used, includes the following steps;

[0016] 1. First, drill 4 holes, numbered as No. 1, No. 2, No. 3 and No. 4, with a diameter of 94 mm. No. 1 and No. 4 are fracturing holes, and No. 2 and No. 3 are injection holes and extraction holes, from top to bottom layer by layer;

[0017] 2. After drilling, connect the single fracturing pipes one by one in borehole No. 1 and borehole No. 4, and use a drilling rig to push them into the borehole. Then put a 20-30 meter galvanized pipe with a diameter of 20mm for gas extraction. Then use a drill pipe to connect the fracturing mechanism and the water injection sealer, and push the water injection sealer to a borehole depth of 8-10m. The water injection sealer is connected to the first main pipe with a cable drill pipe. Use a hand pump to inject water into the water injection sealer. When the water injection pressure reaches 10MPa, stop injecting water and close the pressure stop valve. Finally, use a drilling rig to fix the drill pipe at the end, connect the line, and pull the signal line to a safe area.

[0018] 3. As required, place "two blocking and one injection" mining hole sealers and two sets of 20mm diameter galvanized pipes in borehole No. 2 and borehole No. 3, one set for gas extraction and one set for liquid injection;

[0019] 4. After the laying is completed, the original gas is extracted under the joint witness of the mine owner and the technical guidance party, the gas concentration is tested and recorded, and both parties sign;

[0020] 5. Withdraw personnel and set up alert, start fracturing blasting. When the external microcurrent passes through the detonator, the detonator activates the heating tube, and the heating tube heats up rapidly. Under the influence of the high temperature of the heating tube, the liquid carbon dioxide quickly gasifies and expands sharply. Due to the limited space inside the main pipe, the pressure of the carbon dioxide gas increases rapidly, and the pressure is transmitted along the main pipe to the gasket and the energy-draining plate in turn. Under the action of pressure, the gasket fits tightly between the inner wall of the main pipe and the energy-draining plate, playing a certain sealing and buffering role, ensuring that the pressure can be concentrated on the energy-draining plate. When the pressure inside the main pipe reaches the rupture pressure value of the energy-draining plate, the energy-draining plate ruptures instantly, and the high-pressure carbon dioxide gas quickly passes through the channel formed by the rupture of the energy-draining plate and rushes to the energy-draining head. The energy-draining head guides the high-pressure carbon dioxide gas to the predetermined direction, so that it has a strong impact on the surrounding coal seams and other target areas, generating an expansion pressure of more than 300MPa, and instantly releasing the high-pressure gas to cause the rock to break and loosen, achieving the purpose of fracturing. After 30 minutes, check the working face situation, confirm that there is no abnormality entering the working face, and pull the fracturing equipment out of the borehole with a drilling rig;

[0021] 6. After the blasting is completed, the four boreholes are sealed. First, the grouting head and the bag-type sealer are connected with a quick connector. An appropriate amount of inorganic sealing material is added to the mixing barrel, and then water is added to dilute the inorganic sealing material and water at a weight ratio of 1:1.2. The drive motor is powered on and started. The motor shaft drives the stirring blade to rotate in the mixing barrel to stir and mix the slurry to make it uniform and meet the grouting requirements. The air pump is started to generate a certain negative pressure. The stirred slurry in the mixing barrel is extracted through the slurry extraction pipe. The second pressure gauge monitors the pressure output by the air pump in real time. After the slurry is pressurized by the air pump, it enters the grouting pipe along the grouting head. The grouting pipe transports the slurry to the bag-type sealer. After the bag is filled and expanded, the pressure in the hole rises. When the pressure in the hole reaches the pressure set by the pressure limiting valve of the pneumatic grouting pump, the grouting pump automatically stops working, and the grouting and sealing of the hole is completed.

[0022] 7. After the sealing material solidifies, extract gas again. After 3 to 4 days of extraction, observe the changes in gas concentration and make records in time;

[0023] 8. Use the grouting head to inject gas (fire-proof digestion liquid) and composite colloid fire-proof materials into the No. 2 and No. 3 boreholes through the galvanized pipe. The gas (fire-proof) digestion liquid penetrates into the coal seam and reacts with the gas in the coal seam. The composite colloid fire-proof materials have high water content, which can reduce the temperature of the coal seam and prevent the gas (fire-proof) digestion liquid from overflowing.

[0024] 9. Complete all drilling construction and monitor the gas extraction parameters of the single hole and all drilling holes in the test area;

[0025] All links cooperate with each other and work together to achieve efficient gas control and safe production goals. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the side appearance structure of the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of the coal seam and the No. 1 drill hole cooperating with each other in the present invention;

[0028] Figure 3 This is a schematic diagram of the structure of the No. 2 drill hole and the galvanized pipe cooperating with each other in the present invention;

[0029] Figure 4 This is a schematic diagram of the structure of the water injection hole sealer and the cable drill rod cooperating with each other in the present invention;

[0030] Figure 5 This is a schematic diagram of the structure of the heating pipe and the main pipe cooperating with each other in the present invention;

[0031] Figure 6 This is a schematic diagram of the structure of the water injection pipe and the first pressure gauge cooperating with each other in the present invention;

[0032] Figure 7 It is a schematic diagram of the structure of the bag-type hole sealer and the grouting pipe cooperating with each other in the present invention;

[0033] Figure 8 This is a schematic diagram of the structure in which the motor shaft and stirring blades cooperate with each other in the present invention.

[0034] In the figure: 1, coal seam; 2, No. 1 borehole; 3, No. 2 borehole; 4, No. 3 borehole; 5, No. 4 borehole; 6, galvanized pipe; 7, water injection hole sealer; 8, cable drill rod; 9, fracturing mechanism; 901, detonating head; 902, heating pipe; 903, main pipe; 904, gasket; 905, energy release sheet; 906, energy release head; 10, water injection pipe; 11, first pressure gauge; 12, hand pump ; 13. Base; 14. Mining hole sealer; 15. Bag-type hole sealer; 16. Grouting pipe; 17. Grouting mechanism; 1701. Grouting head; 1702. Air pump; 1703. Second pressure gauge; 1704. Grouting pipe; 1705. Bracket; 1706. Motor plate; 1707. Drive motor; 1708. Motor shaft; 1709. Stirring blade; 1710. Stirring barrel. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] See also Figure 1-8The present invention provides a technical solution: gas-based carbon dioxide fracturing for gas treatment using a gas digester and a construction method thereof, comprising a coal seam 1, a No. 1 borehole 2 is opened on the inner surface of the coal seam 1, a No. 2 borehole 3 is opened on the inner surface of the coal seam 1, a No. 3 borehole 4 is opened on the inner surface of the coal seam 1, a No. 4 borehole 5 is opened on the inner surface of the coal seam 1, a galvanized pipe 6 is connected to the inner surface of the No. 1 borehole 2, a water injection hole sealer 7 is slidably connected to the inner surface of the No. 1 borehole 2, one end of the water injection hole sealer 7 is fixedly connected to a cable drill rod 8, and the cable drill rod A fracturing mechanism 9 is provided at one end of 8, a water injection hole sealer 7 is connected to a water injection pipe 10 at the other end, a first pressure gauge 11 is fixedly connected to one end of the water injection pipe 10, a hand pressure pump 12 is fixedly connected to one side surface of the first pressure gauge 11, a base 13 is fixedly connected to the lower surface of the hand pressure pump 12, a mining hole sealer 14 is connected to the inner surface of the No. 2 borehole 3, a bag-type hole sealer 15 is connected to the inner surface of the No. 2 borehole 3, a grouting pipe 16 is connected to one end of the bag-type hole sealer 15, and a grouting mechanism 17 is provided at one end of the grouting pipe 16;

[0037] The fracturing mechanism 9 includes a detonating head 901, a heating tube 902, a main tube 903, a gasket 904, an energy dissipation sheet 905 and an energy dissipation head 906. One end of the cable drill pipe 8 is connected to the detonating head 901, a heating tube 902 is fixedly connected to one side surface of the detonating head 901, a main tube 903 is threadedly connected to one side surface of the detonating head 901, a gasket 904 is slidably connected to one side surface of the main tube 903, an energy dissipation sheet 905 is slidably connected to one side surface of the main tube 903, and the main tube 906 is slidably connected to one side surface of the main tube 903. The surface of one side of 03 is threadedly connected with an energy-draining head 906. Through the arrangement of the detonating head 901, the heating tube 902, the main tube 903, the gasket 904, the energy-draining sheet 905 and the energy-draining head 906, when in use, the carbon dioxide gas can be converted into liquid under a certain high pressure, and the liquid carbon dioxide is compressed into the main tube 903 by the filling machine. When the external micro-current passes through the detonating head 901, the detonating head 901 activates the heating tube 902, and the heating tube 902 heats up rapidly. Under the influence of the high temperature of the pipe 902, the liquid carbon dioxide is rapidly gasified and its volume expands rapidly. Due to the limited space inside the main pipe 903, the pressure of the carbon dioxide gas increases rapidly, and the pressure is transmitted in turn along the main pipe 903 to the gasket 904 and the energy-draining sheet 905. Under the action of pressure, the gasket 904 is tightly fitted between the inner wall of the main pipe 903 and the energy-draining sheet 905, playing a certain sealing and buffering role, ensuring that the pressure can be concentrated on the energy-draining sheet 905. When the pressure inside the main pipe 903 reaches the rupture pressure value of the energy-draining sheet 905, the energy-draining sheet 905 ruptures instantly, and the high-pressure carbon dioxide gas quickly passes through the channel formed by the rupture of the energy-draining sheet 905 and rushes to the energy-draining head 906. The energy-draining head 906 guides the high-pressure carbon dioxide gas to a predetermined direction, so that it has a strong impact on the surrounding target areas such as the coal seam 1, generates an expansion pressure of more than 300 MPa, and instantly releases the high-pressure gas to cause the rock to break and loosen, thereby achieving the purpose of fracturing.

[0038] Furthermore, borehole No. 1 2 corresponds to borehole No. 4 5, which is a fracturing borehole with a borehole diameter of 94 mm. Through the setting of borehole No. 1 2 and borehole No. 4 5, when in use, after drilling, single fracturing pipes are connected one by one in borehole No. 1 2 and borehole No. 4 5, and a drilling rig is used to push them into the borehole, and then a 20-30 meter galvanized pipe 6 with a diameter of 20 mm is placed in it for gas extraction. Then, a drill rod is used to connect the fracturing mechanism 9 and the water injection sealer 7, and the water injection sealer 7 is pushed to the borehole depth of 8 to 10 m. The water injection sealer 7 is connected to the first main pipe 903 with a cable drill rod 8, and a hand pump 12 is used to inject water into the water injection sealer 7. When the water injection pressure reaches 10 MPa, the water injection is stopped and the pressure cut-off valve is closed. Finally, a drilling rig is used to fix the drill rod at the end, the line is connected, and the signal line is pulled to a safe area.

[0039] Furthermore, borehole No. 2 3 and borehole No. 3 4 correspond to each other and are injection holes and extraction holes with a borehole diameter of 94 mm. Through the setting of borehole No. 2 3 and borehole No. 3 4, when in use, "two blockages and one injection" mining sealers 14 and two sets of galvanized pipes 6 with a diameter of 20 mm are placed in borehole No. 2 3 and borehole No. 3 4 as required, one set for gas extraction and the other set for injection.

[0040] Furthermore, the size of the galvanized pipe 6 is 20 mm, and multiple groups are arranged in the drilled hole. Through the arrangement of the galvanized pipe 6, when in use, the multiple groups of galvanized pipes 6 work together in the entire gas management system. On the one hand, the galvanized pipe 6 used for gas extraction continuously extracts the gas in the coal seam 1 to reduce the gas pressure and concentration. On the other hand, the galvanized pipe 6 used for injecting the medium timely injects the gas digester into the coal seam 1 to reduce the generation of gas from the source or change the state of the gas. The two cooperate with each other to jointly realize the effective management and control of gas and ensure the safe conduct of underground mining operations such as coal mines.

[0041] Furthermore, multiple groups of main pipes 903 are arranged inside borehole No. 1, and liquid carbon dioxide can be filled inside the main pipes 903. Through the arrangement of the main pipes 903, when in use, when multiple groups of main pipes 903 work simultaneously, the high-pressure gases they generate cooperate with each other to form a complex pressure field in the coal seam 1. This pressure field can further expand and connect the cracks and pores in the coal seam 1, thereby destroying the structure of the coal seam 1 and promoting the release and flow of gas.

[0042] Furthermore, two groups of gaskets 904 are provided, and the material of gaskets 904 is a composite material of rubber and metal. Through the setting of gaskets 904, when in use, gaskets 904 are tightly fitted between the inner wall of the main pipe 903 and the energy dissipation sheet 905 under pressure, playing a certain sealing and buffering role, ensuring that the pressure can be concentrated on the energy dissipation sheet 905.

[0043] Furthermore, the grouting mechanism 17 includes a grouting head 1701, an air pump 1702, a second pressure gauge 1703, a grouting pipe 1704, a bracket 1705, a motor plate 1706, a drive motor 1707, a motor shaft 1708, a stirring blade 1709 and a stirring barrel 1710. One end of the grouting pipe 16 is fixedly connected to the grouting head 1701, one end of the grouting head 1701 is fixedly connected to the air pump 1702, one side surface of the air pump 1702 is fixedly connected to the second pressure gauge 1703, the lower surface of the air pump 1702 is fixedly connected to the grouting pipe 1704, and the air pump The lower surface of bracket 1702 is fixedly connected with bracket 1705, the upper surface of bracket 1705 is fixedly connected with motor plate 1706, the upper surface of motor plate 1706 is fixedly connected with driving motor 1707, the lower surface of driving motor 1707 is fixedly connected with motor shaft 1708, the outer surface of motor shaft 1708 is fixedly connected with stirring blade 1709, the lower surface of bracket 1705 is fixedly connected with stirring bucket 1710, and the grouting head 1701, air pump 1702, second pressure gauge 1703, grouting pipe 1704, bracket 1705, electric The machine plate 1706, the driving motor 1707, the motor shaft 1708, the stirring blade 1709 and the stirring barrel 1710 are arranged. When in use, the grouting head 1701 is first connected to the bag-type sealer 15 with a quick connector, and an appropriate amount of inorganic sealing material is added to the stirring barrel 1710, and then water is added to dilute the inorganic sealing material at a weight ratio of 1:1.2 to water. The driving motor 1707 is powered on and started, and the stirring blade 1709 is driven by the motor shaft 1708 to rotate in the stirring barrel 1710 to stir and mix the slurry to make it uniform and When the state meets the requirements for grouting, the air pump 1702 is started to generate a certain negative pressure, and the stirred slurry in the mixing barrel 1710 is extracted through the slurry extraction pipe 1704. The second pressure gauge 1703 monitors the pressure output by the air pump 1702 in real time. After the slurry is pressurized by the air pump 1702, it enters the grouting pipe 16 along the grouting head 1701. The grouting pipe 16 transports the slurry to the bag-type hole sealer 15. After the bag is filled and expanded, the pressure in the hole rises. When the pressure in the hole reaches the pressure set by the pressure limiting valve of the pneumatic grouting pump, the grouting pump automatically stops working, and the grouting and sealing of the hole is completed.

[0044] Furthermore, the motor shaft 1708 passes through the motor plate 1706 and is rotatably connected to the motor plate 1706. Multiple groups of stirring blades 1709 are arranged on the surface of the motor shaft 1708. Through the arrangement of the motor plate 1706, when in use, the motor plate 1706 provides a stable installation platform for the drive motor 1707, ensuring that the drive motor 1707 can operate normally and transmit power to the motor shaft 1708 and the stirring blades 1709 without affecting the stirring effect and the overall performance of the equipment due to vibration or instability.

[0045] Furthermore, a filter is provided inside the grouting head 1701, and the grouting pipe 1704 is made of corrosion-resistant rubber or plastic material. Through the setting of the grouting head 1701, when in use, the fine pores of the filter can block the passage of these impurities, ensuring that only slurry that meets the particle size requirements can continue to flow to the air pump 1702 and subsequent grouting channels, thereby preventing larger particles of impurities from clogging the grouting pipe 16, the air pump 1702 or affecting the grouting effect.

[0046] Working principle: 1. First, 4 holes are drilled, numbered as No. 1 hole 2, No. 2 hole 3, No. 3 hole 4 and No. 4 hole 5, with a diameter of 94mm. No. 1 hole 2 and No. 4 hole 5 are fracturing holes, and No. 2 hole 3 and No. 3 hole 4 are injection holes and extraction holes, which are carried out layer by layer from top to bottom;

[0047] 2. After drilling, connect the single fracturing pipes one by one in the No. 1 borehole 2 and the No. 4 borehole 5, and use a drilling rig to push them into the borehole. Then put a 20-30 meter galvanized pipe 6 with a diameter of 20 mm for gas extraction. Then use a drill pipe to connect the fracturing mechanism 9 and the water injection hole sealer 7, and push the water injection hole sealer 7 to the borehole depth of 8-10m. The water injection hole sealer 7 and the first main pipe 903 are connected by a cable drill pipe 8. Use a hand pump 12 to inject water into the water injection hole sealer 7. When the water injection pressure reaches 10MPa, stop injecting water and close the pressure stop valve. Finally, use a drilling rig to fix the drill pipe at the end, connect the line, and pull the signal line to a safe area.

[0048] 3. As required, put "two blocking and one injection" mining hole sealers 14 and two sets of 20mm diameter galvanized pipes 6 into the No. 2 borehole 3 and the No. 3 borehole 4, one set for gas extraction and one set for liquid injection;

[0049] 4. After the laying is completed, the original gas is extracted under the joint witness of the mine owner and the technical guidance party, the gas concentration is tested and recorded, and both parties sign;

[0050] 5. Withdraw personnel and set up alert, start fracturing blasting. When external microcurrent passes through the detonator 901, the detonator 901 activates the heating tube 902, and the heating tube 902 heats up rapidly. Under the influence of the high temperature of the heating tube 902, the liquid carbon dioxide gasifies rapidly and expands sharply. Due to the limited space inside the main pipe 903, the pressure of the carbon dioxide gas increases rapidly. The pressure is transmitted along the main pipe 903 to the gasket 904 and the energy-draining sheet 905 in turn. Under the action of pressure, the gasket 904 fits tightly between the inner wall of the main pipe 903 and the energy-draining sheet 905, playing a certain sealing and buffering role, ensuring that the pressure can be concentrated on the discharge. Energy sheet 905, when the pressure inside main pipe 903 reaches the rupture pressure value of energy sheet 905, energy sheet 905 ruptures instantly, and high-pressure carbon dioxide gas quickly passes through the channel formed by the rupture of energy sheet 905 and rushes to energy sheet head 906. Energy sheet head 906 guides high-pressure carbon dioxide gas to a predetermined direction, so that it has a strong impact on the surrounding target areas such as coal seam 1, generates an expansion pressure of more than 300MPa, and instantly releases high-pressure gas to cause rock fracture and loosening, achieving the purpose of fracturing. After 30 minutes, check the working face situation, confirm that there is no abnormality in entering the working face, and pull the fracturing equipment out of the borehole with a drilling rig;

[0051] 6. After the blasting is completed, the four boreholes are sealed. The grouting head 1701 is first connected to the bag-type sealer 15 with a quick connector. An appropriate amount of inorganic sealing material is added to the mixing barrel 1710. Water is then added to dilute the inorganic sealing material at a weight ratio of 1:1.2. The drive motor 1707 is powered on and started. The motor shaft 1708 drives the stirring blade 1709 to rotate in the stirring barrel 1710 to stir and mix the slurry to make it uniform and meet the grouting requirements. The air pump 170 2 is started, a certain negative pressure is generated, and the slurry stirred in the mixing barrel 1710 is extracted through the slurry extraction pipe 1704. The second pressure gauge 1703 monitors the pressure output by the air pump 1702 in real time. After the slurry is pressurized by the air pump 1702, it enters the grouting pipe 16 along the grouting head 1701. The grouting pipe 16 transports the slurry to the bag-type hole sealer 15. After the bag is filled and expanded, the pressure in the hole rises. When the pressure in the hole reaches the pressure set by the pressure limiting valve of the pneumatic grouting pump, the grouting pump automatically stops working, and the grouting and sealing of the hole is completed;

[0052] 7. After the sealing material solidifies, extract gas again. After 3 to 4 days of extraction, observe the changes in gas concentration and make records in time;

[0053] 8. Use the grouting head 1701 to inject gas (fire-proof digestion liquid) and composite colloid fire-proof material into the No. 2 borehole 3 and the No. 3 borehole 4 through the galvanized pipe 6. The gas (fire-proof) digestion liquid penetrates into the coal seam 1 and reacts with the gas in the coal seam 1. The composite colloid fire-proof material has a high water content, which can reduce the temperature of the coal seam 1 and prevent the gas (fire-proof) digestion liquid from overflowing.

[0054] 9. Complete all drilling construction and monitor the gas extraction parameters of the single hole and all drilling holes in the test area;

[0055] All links cooperate with each other and work together to achieve the goals of efficient gas control and safe production, thus completing the carbon dioxide fracturing and construction method for gas control based on gas digesters.

[0056] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for treating gas by fracturing with carbon dioxide based on a gas digester and a construction method thereof, comprising a coal seam (1), characterized in that: The inner surface of the coal seam (1) is provided with a No. 1 borehole (2), the inner surface of the coal seam (1) is provided with a No. 2 borehole (3), the inner surface of the coal seam (1) is provided with a No. 3 borehole (4), the inner surface of the coal seam (1) is provided with a No. 4 borehole (5), the inner surface of the No. 1 borehole (2) is connected with a galvanized pipe (6), the inner surface of the No. 1 borehole (2) is slidably connected with a water injection hole sealer (7), one end of the water injection hole sealer (7) is fixedly connected with a cable drill rod (8), one end of the cable drill rod (8) is provided with a fracturing mechanism (9), the water injection hole sealer (7) is provided with a galvanized pipe (6) and the inner surface of the No. 1 borehole (2) is slidably connected with a water injection hole sealer (7), one end of the water injection hole sealer (7) is fixedly connected with a cable drill rod (8), one end of the cable drill rod (8) is provided with a fracturing mechanism (9), and the water injection hole sealer (7) is provided with a galvanized pipe (6) and a galvanized pipe (6) is connected with the inner surface of the No. 1 borehole (2). ) is connected to a water injection pipe (10) at the other end, one end of the water injection pipe (10) is fixedly connected to a first pressure gauge (11), a side surface of the first pressure gauge (11) is fixedly connected to a hand pump (12), a lower surface of the hand pump (12) is fixedly connected to a base (13), the inner surface of the No. 2 borehole (3) is connected to a mining hole sealer (14), the inner surface of the No. 2 borehole (3) is connected to a bag-type hole sealer (15), one end of the bag-type hole sealer (15) is connected to a grouting pipe (16), and one end of the grouting pipe (16) is provided with a grouting mechanism (17); The fracturing mechanism (9) comprises an initiating head (901), a heating tube (902), a main tube (903), a gasket (904), an energy dissipation sheet (905) and an energy dissipation head (906); one end of the cable drill pipe (8) is connected to the initiating head (901); a heating tube (902) is fixedly connected to a surface of one side of the initiating head (901); a main tube (903) is threadedly connected to a surface of one side of the initiating head (901); a gasket (904) is slidably connected to a surface of one side of the main tube (903); an energy dissipation sheet (905) is slidably connected to a surface of one side of the main tube (903); and an energy dissipation head (906) is threadedly connected to a surface of one side of the main tube (903).

2. The carbon dioxide fracturing method for treating gas based on gas digestion agent and its construction method according to claim 1 is characterized in that: The No. 1 borehole (2) corresponds to the No. 4 borehole (5), which is a construction fracturing borehole with a borehole diameter of 94 mm.

3. The carbon dioxide fracturing method for treating gas based on gas digestion agent and its construction method according to claim 1 is characterized in that: The No. 2 borehole (3) corresponds to the No. 3 borehole (4), which is a liquid injection hole and a pumping hole, and the borehole diameter is 94 mm.

4. The carbon dioxide fracturing method for treating gas based on gas digestion agent and its construction method according to claim 1 is characterized in that: The size of the galvanized pipe (6) is 20 mm, and multiple groups are arranged in the drilled hole.

5. The carbon dioxide fracturing method for treating gas based on gas digestion agent and its construction method according to claim 1 is characterized in that: The main pipes (903) are arranged in multiple groups inside the No. 1 borehole (2), and the inside of the main pipes (903) can be filled with liquid carbon dioxide.

6. The carbon dioxide fracturing method for treating gas based on gas digestion agent and its construction method according to claim 1 is characterized in that: Two groups of gaskets (904) are provided, and the material of the gaskets (904) is a composite material of rubber and metal.

7. The carbon dioxide fracturing method for treating gas based on gas digestion agent and its construction method according to claim 1 is characterized in that: The grouting mechanism (17) comprises a grouting head (1701), an air pump (1702), a second pressure gauge (1703), a grouting pipe (1704), a bracket (1705), a motor plate (1706), a driving motor (1707), a motor shaft (1708), a stirring blade (1709) and a stirring barrel (1710); one end of the grouting pipe (16) is fixedly connected to the grouting head (1701); one end of the grouting head (1701) is fixedly connected to the air pump (1702); one side surface of the air pump (1702) is fixedly connected to the second pressure gauge (1703); the air pump (1706) is fixedly connected to the second pressure gauge (1703); 02) is fixedly connected to a slurry suction pipe (1704) on its lower surface, the air pump (1702) is fixedly connected to a bracket (1705) on its lower surface, the bracket (1705) is fixedly connected to a motor plate (1706) on its upper surface, the motor plate (1706) is fixedly connected to a drive motor (1707) on its upper surface, the drive motor (1707) is fixedly connected to a motor shaft (1708) on its lower surface, a stirring blade (1709) is fixedly connected to the outer surface of the motor shaft (1708), and the bracket (1705) is fixedly connected to a stirring barrel (1710) on its lower surface.

8. The carbon dioxide fracturing method for treating gas based on gas digestion agent and its construction method according to claim 7 is characterized in that: The motor shaft (1708) passes through the motor plate (1706) and is rotationally connected to the motor plate (1706), and a plurality of stirring blades (1709) are arranged on the surface of the motor shaft (1708).

9. The carbon dioxide fracturing method for treating gas based on gas digestion agent and its construction method according to claim 7, characterized in that: The grouting head (1701) is provided with a filter screen inside, and the grouting pipe (1704) is made of corrosion-resistant rubber or plastic material.

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