A blasting permeability enhancement water injection process and method

Abstract

The present invention provides a blasting permeability enhancement water injection process and method, and relates to the technical field of coal seam water injection. The blasting permeability enhancement water injection process for coal seams comprises a water injection system, a blasting system, and a sealing system. The blasting permeability enhancement water injection method for coal seams of the present invention uses the blasting permeability enhancement water injection process of the present invention to perform multiple drillings on a coal body, wherein the drilling holes are arranged to form a polygon, the water injection drilling holes are located at the corners of the polygon, and the water injection blasting drilling holes are located at the exact center of the polygon. After water is injected into each borehole, explosives are placed in the central water injection blasting borehole for blasting to loosen and blast the coal body around the borehole, thereby expanding the range of loosening and crushing in the coal body around the borehole and improving the permeability of the coal body. Afterwards, water is continuously injected into each borehole to fully wet the coal body to reduce the generation of dust, enhance the plasticity of the coal body, further alleviate the stress concentration in the coal body, and reduce the danger of coal and gas outburst during tunnel excavation.

Description

Technical Field

[0001] The invention belongs to the technical field of coal seam water injection, and in particular relates to a blasting permeability-enhancing water injection process and method. Background Art

[0002] In recent years, with the increase in coal production year by year and the continuous improvement of the mechanization degree in the coal mining process, the problem of coal mine dust hazards has become particularly prominent. Coal seam water injection technology, as one of the main safety production technical measures for coal mine dust prevention and control, has been widely used at home and abroad. Coal seam water injection is to pre-wet the unmined coal body with water, that is, before the coal seam is mined, pressurized water is injected into the coal body through the construction drilling hole to penetrate into the pores and cracks of the coal body, destroy the integrity of the coal body, reduce the brittleness of the coal body, and enhance the plasticity, thereby changing the physical and mechanical properties of the coal body, making the coal body lose its impact tendency, thereby achieving the effect of softening the coal body. The presence of water can moisten the original coal dust in the coal body, making it lose the ability to fly, effectively wrapping every small part of the coal body, and when the coal body is broken during mining, it avoids the flying of fine coal dust. The wetting effect of water enhances the plasticity of the coal body and reduces the brittleness. When the coal body is subjected to external force, many brittle fractures are transformed into plastic deformation, thereby greatly reducing the possibility of the coal body being broken into dust particles and reducing the amount of coal dust generated.

[0003] In the initial state of coal seam water injection, water enters the coal body along the original connected cracks of the coal body driven by external pressure. The cracks are the main transmission channels of the fluid. Since there are a large number of micropores in the coal body and gas is stored in the micropores, under the action of gas resistance, water cannot enter the too fine pores to more effectively wet the coal body. Micropores are the main component of the dual porous structure of coal seams, and their water content determines the overall wetting degree of the coal seam. Therefore, the field of coal seam water injection engineering urgently needs new water injection efficiency enhancement technologies to improve the wetting and disaster prevention effects of water injection on coal seams. Summary of the invention

[0004] The object of the present invention is to provide a blasting permeability enhancement water injection process and method to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions: a blasting permeability enhancement water injection process and method, the above water injection system, blasting system, sealing system, pressure monitoring system and control unit;

[0006] The water injection system includes a single-port water injection system and a double-port water injection system. The single-port water injection system is composed of a sealer water injection pipe, a sealer water injection pump and a main water tank, and the double-port water injection system is composed of a water injection pipeline, a water injection operation table, a table water pump and an auxiliary water tank.

[0007] The water inlet end of the hole sealer water injection pump is connected to the main water tank, and the water outlet end of the hole sealer water injection pump is connected to the hole sealer water injection pipe;

[0008] The water inlet of the water pump is connected to the auxiliary water tank, the water outlet of the water pump is connected to the water inlet of the water injection operation table, and the water outlet of the water injection operation table is connected to the water injection pipeline;

[0009] The blasting system comprises a blasting chamber, explosives, a firing line and an igniter, wherein the igniter is connected to the explosives in the blasting chamber via cables of the firing line;

[0010] The above-mentioned sealing system includes a single-port sealing system and a double-port sealing system. The above-mentioned single-port sealing system includes a water injection pipeline, a water injection operation table, a water pump, an auxiliary water tank and a single-port sealing device. The above-mentioned double-port sealing system includes a double-port sealing device, a sealing device water injection pipe, a sealing device water injection pump and a main water tank;

[0011] The water injection pipeline is connected to a single-hole sealing device;

[0012] The double-mouth hole sealer is connected to the hole sealer water injection pipe;

[0013] The pressure monitoring system comprises a pressure sensor and a pressure detection station, and the pressure detection station is connected to the pressure sensor via a signal cable.

[0014] Preferably, the double-port hole sealer comprises a water injection port, a rubber capsule and a water outlet, and the water injection port comprises a drilling water injection port and a hole sealer water injection port.

[0015] Preferably, the rubber bladder is made of modified rubber.

[0016] Preferably, the above-mentioned drilled water injection port is made of stainless steel.

[0017] Preferably, the water injection operation table is arranged on a side of the water injection pipeline close to the water pump.

[0018] Preferably, the blasting system further includes a safety rope.

[0019] Preferably, a pressure gauge and a water injection valve are provided in the water injection operating table.

[0020] A method for blasting permeability enhancement water injection process, the specific steps are as follows:

[0021] S1. Drill water injection boreholes in a polygonal arrangement on the roadway coal seam, and drill a water injection blasting borehole in the center of the polygon;

[0022] S2, extending the blasting chamber containing explosives into the water injection blasting borehole located at the center of the polygon, with the bottom of the explosives close to the bottom of the hole, and the blasting line and safety rope connected to the blasting chamber are led out of the borehole;

[0023] S3, inserting a double-mouth hole sealer into the water injection blasting borehole, with the water outlet end of the double-mouth hole sealer extending into the water injection blasting borehole, and inserting a single-mouth hole sealer into the water injection borehole arranged in a polygonal manner;

[0024] S4, injecting water into the double-mouth hole sealer of the water injection blasting borehole through the hole sealer water injection pipe;

[0025] S5, injecting water into the single-hole sealer of the water injection borehole through the water injection pipeline;

[0026] S6. Observe the internal pressure of the water injection blasting borehole and the water injection borehole;

[0027] S7, the internal pressure of the water injection blasting borehole and the water injection borehole continues to rise. When the internal pressure of the water injection blasting borehole and the water injection borehole reaches the set pressure value, the control unit controls the water injection operation console to stop water injection;

[0028] S8. After the water injection is completed, turn on the igniter to ignite the blasting line to carry out the blasting operation. If the explosives refuse to explode, first release the water pressure of the hole sealer and remove the hole sealer, and retrieve the explosives by pulling the safety rope;

[0029] S9, after the blasting is finished, the pressure in the water injection blasting borehole first rises at the moment of blasting and then quickly drops to the set pressure value, and the control unit restarts the water injection;

[0030] S10: The borehole internal pressure continues to rise and water injection is completed.

[0031] Technical effects and advantages of the present invention:

[0032] The blasting permeability enhancement water injection process and method, during the water injection process of the water injection system, by placing explosives in the borehole for blasting, the coal body around the borehole is loosened and blasted, the range of loosening and crushing in the coal body around the borehole is expanded, the number of cracks is increased, and a new crack network is formed with the original cracks in the coal body, the permeability of the coal body is improved, and under the action of the shock wave generated by the blasting, the water in the surrounding boreholes and the coal body is quickly pushed into the newly generated cracks and pores, thereby expanding the wetting range of the coal body. The water pressure in the borehole is reduced, and water is continued to be injected into the borehole to fully wet the coal body, enhance the plasticity of the coal body, further alleviate the stress concentration in the coal body, and reduce the danger of coal and gas outburst during tunnel excavation. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of the blasting permeability enhancement water injection process according to an embodiment of the present invention;

[0034] Figure 2 It is a schematic diagram of the plan layout of drilling holes in the blasting permeability enhancement and water injection process according to an embodiment of the present invention.

[0035] In the figure: 1. Coal seam in tunnel; 2. Water injection blasting drilling; 3. Blasting chamber; 4. Explosives; 5. Blast line; 6. Safety rope; 7. Double-mouth hole sealer; 8. Water injection pipe for hole sealer; 9. Water injection pump for hole sealer; 10. Main water tank; 11. Ignitor; 12. Water injection pipeline; 13. Water injection operation table; 14. Water pump; 15. Auxiliary water tank; 16. Control unit; 17. Pressure sensor; 18. Pressure detection station; 19. Single-mouth hole sealer; 20. Water injection drilling. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention will be described clearly and completely 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.

[0037] Please refer to Figure 1-Figure 2 The blasting permeability enhancement water injection process and method shown includes a water injection system, a blasting system, a sealing system, a pressure monitoring system and a control unit 16;

[0038] The water injection system includes a single-port water injection system and a double-port water injection system. The single-port water injection system is composed of a sealer water injection pipe 8, a sealer water injection pump 9 and a main water tank 10, and the double-port water injection system is composed of a water injection pipeline 12, a water injection operation table 13, a table water pump 14 and an auxiliary water tank 15.

[0039] The water inlet end of the hole sealing device water injection pump 9 is connected to the main water tank 10, and the water outlet end of the hole sealing device water injection pump 9 is connected to the hole sealing device water injection pipe 8;

[0040] The water inlet of the water pump 14 is connected to the auxiliary water tank 15, the water outlet of the water pump 14 is connected to the water inlet of the water injection operation table 13, and the water outlet of the water injection operation table 13 is connected to the water injection pipeline 12;

[0041] The blasting system includes a blasting chamber 3, explosives 4, a firing line 5 and an igniter 11. The igniter 11 is connected to the explosives 4 in the blasting chamber 3 via cables of the firing line 5. The explosives 4 are arranged inside the blasting chamber 3 to prevent the explosives 4 from being damaged and refusing to explode by being soaked in pressurized water in the borehole. The blasting chamber 3 is made of plastic material.

[0042] The sealing system includes a single-port sealing system and a double-port sealing system. The single-port sealing system includes a water injection pipeline 12, a water injection operation table 13, a water pump 14, an auxiliary water tank 15 and a single-port sealer 19. The double-port sealing system includes a double-port sealer 7, a sealer water injection pipe 8, a sealer water injection pump 9 and a main water tank 10. The water injection operation table 13, the igniter 11 and the pressure detection station 18 are respectively connected to the control unit 16 via signal cables.

[0043] refer to Figure 1-Figure 2The water injection pipeline 12 is connected to the single-port hole sealer 19, and the double-port hole sealer 7 is connected to the hole sealer water injection pipe 8. The pressure monitoring system includes a pressure sensor 17 and a pressure detection station 18. The pressure detection station 18 is connected to the pressure sensor 17 via a signal cable. The pressure sensor 17 is arranged on the outer wall of the hole sealer water outlet. When the hole sealer is inserted into the borehole, the pressure sensor 17 can be inserted into the borehole together. The double-port hole sealer 7 includes a water injection port, a rubber capsule and a water outlet. The water injection port includes a drilling water injection port and a hole sealer water injection port. The rubber capsule is made of modified rubber, and the drilling water injection port is made of stainless steel. The water injection operation table 13 is arranged on the side of the water injection pipeline 12 close to the water pump 14. The blasting system also includes a safety rope 6, which is used to pull the safety rope 6 to retrieve the blasting chamber 3 when the explosives are not exploded. Valves, flow meters and pressure gauges are set in the water injection operation table 13 to adjust the flow rate, pressure and other parameters of the pressure water output by the water injection pipeline 12.

[0044] refer to Figure 1-Figure 2 , a method for blasting permeability enhancement water injection process, the specific steps are as follows:

[0045] S1, drilling water injection boreholes 20 in a polygonal arrangement on the roadway coal seam 1, and drilling water injection blasting boreholes 2 in the center of the polygon, according to the layout of the coal mining area roadway and the coal mining method, combined with the occurrence characteristics of the coal seam, select the appropriate drilling layout, drilling length, drilling spacing, drilling equipment and water injection pump, etc.;

[0046] S2, extending the blasting chamber 3 containing explosives 4 into the water injection blasting borehole 2 located at the center of the polygon, with the bottom of the explosives 4 close to the bottom of the hole, and the blasting line 5 and safety rope 6 connected to the blasting chamber 3 are led out of the borehole;

[0047] S3, insert the double-mouth sealer 7 into the water injection blasting borehole 2, the outlet end of the double-mouth sealer 7 extends into the water injection blasting borehole 2, and the single-mouth sealer 19 is inserted into the polygonal water injection borehole 20;

[0048] S4, injecting water into the double-mouth sealer 7 of the water injection blasting borehole 2 through the sealer water injection pipe 8, the internal pressure of the double-mouth sealer 7 increases, the volume of the sealer continues to expand, thereby blocking the borehole;

[0049] S5, injecting water into the single-hole sealer 19 of the water injection borehole 20 through the water injection pipeline 12, and the pressure in the water injection borehole 20 begins to rise, indicating that the pressure water fills the water injection borehole 20;

[0050] S6, observe the internal pressure of the water injection blasting borehole 2 and the water injection borehole 20. When the pressure in the water injection borehole 20 increases slowly or floats slightly, it indicates that the filtration loss stage has begun;

[0051] S7, the internal pressure of the water injection blasting borehole 2 and the water injection borehole 20 continues to rise. When the internal pressure of the water injection blasting borehole 2 and the water injection borehole 20 reaches the set pressure value P1, the control unit 16 controls the water injection operation station 13 to stop water injection;

[0052] S8, after the water injection is completed, the igniter 11 is turned on to ignite the blasting line 5 to carry out the blasting operation. If the explosive 4 refuses to explode, the water pressure of the hole sealer is firstly released and the hole sealer is taken out, and the explosive 4 is retrieved by pulling the safety rope 6 to avoid the explosive 4 remaining in the coal body, thereby ensuring the safety of the blasting;

[0053] S9, after the blasting is finished, the pressure in the water injection blasting borehole 2 first rises at the moment of blasting and then rapidly drops to the set pressure value, the control unit 16 restarts the water injection, the loosening blasting is combined with the coal seam water injection, the coal body around the borehole is disturbed by the loosening blasting, so that the original stress field inside it is redistributed, and new cracks are generated, forming a new crack network with the original cracks, thereby improving the permeability of the coal body, and the shock wave generated by the blasting action drives the existing water in the water injection borehole 20 and the coal body to move to the newly added crack network, thereby achieving the purpose of wetting the coal body in a wider range, at this time, the pressure in the borehole first rises at the moment of blasting and then rapidly drops to the set pressure value P2, and the control unit 16 opens the water injection valve;

[0054] S10, the borehole pressure continues to rise and the water injection is completed. The borehole pressure continues to rise, indicating that it has entered the third saturation stage and the water injection is completed.

[0055] Working principle:

[0056] The blasting permeability enhancement water injection process and method, the water injection system includes an auxiliary water tank 15, a water pump 14, a water injection operation table 13 and a water injection pipeline 12, the water inlet end of the water pump 14 is connected to the auxiliary water tank 15, and the water outlet end of the water pump 14 is connected to the water injection pipeline 12. The water injection operation table 13 is arranged on the side of the water injection pipeline 12 close to the water pump 14, and the water injection operation table 13 in this embodiment is provided with valves, flow meters and pressure meters, etc., for adjusting the flow rate, pressure and other parameters of the pressure water output by the water injection pipeline 12.

[0057] The blasting system includes an igniter 11, a firing line 5, a safety rope 6, a blasting chamber 3 and explosives 4. The firing line 5 connects the igniter 11 and the explosives 4, and the safety rope 6 connects the blasting chamber 3, and is used to pull the safety rope 6 to retrieve the blasting chamber 3 when the explosives 4 are not exploded.

[0058] The sealing system includes a double-port hole sealer 7, a single-port hole sealer 19, a hole sealer water injection pipe 8, a hole sealer water injection pump 9, and a main water tank 10. The double-port hole sealer 7 is connected to the hole sealer water injection pump 9 via the hole sealer water injection pipe 8, and the single-port hole sealer 19 is connected to the water injection operating table 13 via the water injection pipeline 12.

[0059] The explosive 4 is arranged inside the blasting chamber 3 to prevent the explosive 4 from being damaged by the pressure water in the borehole and causing explosion failure. Specifically, the end of the blasting chamber 3 is closed and close to the bottom of the borehole, the top of the blasting chamber 3 is closed, and the blasting line 5 is connected to the internal explosive 4 through the hole reserved at the top of the blasting chamber 3, wherein the blasting chamber 3 is made of plastic material. In this way, the explosive 4 can be prevented from being damaged by the pressure water in the borehole and causing explosion failure.

[0060] The pressure monitoring system includes a pressure detection station 18 and a pressure sensor 17. The pressure detection station 18 is connected to the pressure sensor 17 via a signal cable. The pressure sensor 17 is arranged on the outer wall of the water outlet of the hole sealer. When the hole sealer is inserted into the borehole, the pressure sensor 17 can be inserted into the borehole together.

[0061] The water injection operation table 13, the igniter 11, and the pressure detection station 18 are connected to the control unit 16 via signal cables. The control unit 16 in this example is set as a computer. The control unit 16 is installed with an intelligent recognition program. The control unit 16 recognizes the pressure data change characteristics of the pressure detection station 18 in real time. The control unit 16 controls the opening and closing of the water injection operation table 13 and the igniter 11 according to the pressure data change characteristics.

[0062] The above description is only a preferred specific implementation manner of the invention, but the protection scope of the invention is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or changes within the technical scope disclosed by the invention according to the technical scheme and inventive concept of the invention, which should be covered by the protection scope of the invention.

Claims

1. A blasting permeability enhancement water injection method, characterized in that: The specific steps are as follows: S1, drilling water injection boreholes (20) in a polygonal arrangement on the roadway coal seam (1), and drilling a water injection blasting borehole (2) in the center of the polygon; S2, extending the blasting chamber (3) containing explosives (4) into the water injection blasting borehole (2) located at the center of the polygon, with the bottom of the explosives (4) close to the bottom of the hole, and the blasting line (5) and safety rope (6) connected to the blasting chamber (3) are led out of the borehole; S3, inserting the double-mouth hole sealer (7) into the water injection blasting borehole (2), with the water outlet end of the double-mouth hole sealer (7) extending into the water injection blasting borehole (2), and inserting the single-mouth hole sealer (19) into the polygonal water injection borehole (20); S4, injecting water into the double-mouth hole sealer (7) of the water injection blasting borehole (2) through the hole sealer water injection pipe (8); S5, injecting water into the single-port sealer (19) of the water injection borehole (20) through the water injection pipeline (12); S6. Observe the internal pressure of the water injection blasting borehole (2) and the water injection borehole (20); S7, the internal pressure of the water injection blasting borehole (2) and the water injection borehole (20) continues to rise, and when the internal pressure of the water injection blasting borehole (2) and the water injection borehole (20) reaches a set pressure value, the control unit (16) controls the water injection operation console (13) to stop water injection; S8, after the water injection is completed, the igniter (11) is turned on to ignite the blasting line (5) to carry out the blasting operation. If it is found that the explosive (4) refuses to explode, the water pressure of the hole sealer is first released and the hole sealer is removed, and the explosive (4) is retrieved by pulling the safety rope (6); S9, after the blasting is completed, the pressure in the water injection blasting borehole (2) first rises at the moment of blasting and then quickly drops to the set pressure value, and the control unit (16) restarts the water injection; S10: The borehole internal pressure continues to rise and water injection is completed.

2. A blasting permeability enhancement water injection system, used in a blasting permeability enhancement water injection method as claimed in claim 1, characterized in that: It comprises a water injection system, a blasting system, a hole sealing system, a pressure monitoring system and a control unit (16), and is characterized in that: the water injection system comprises a single-port water injection system and a double-port water injection system, the single-port water injection system is composed of a hole sealing device water injection pipe (8), a hole sealing device water injection pump (9) and a main water tank (10), and the double-port water injection system is composed of a water injection pipeline (12), a water injection operation table (13), a table water pump (14) and an auxiliary water tank (15); The water inlet end of the hole sealing device water injection pump (9) is connected to the main water tank (10), and the water outlet end of the hole sealing device water injection pump (9) is connected to the hole sealing device water injection pipe (8); The water inlet end of the water pump (14) is connected to the auxiliary water tank (15), the water outlet end of the water pump (14) is connected to the water inlet end of the water injection operation table (13), and the water outlet end of the water injection operation table (13) is connected to the water injection pipeline (12); The blasting system comprises a blasting chamber (3), explosives (4), a firing line (5) and an igniter (11), wherein the igniter (11) is connected to the explosives (4) in the blasting chamber (3) via cables of the firing line (5); The sealing system comprises a single-port sealing system and a double-port sealing system. The single-port sealing system comprises a water injection pipeline (12), a water injection operation table (13), a water pump (14), an auxiliary water tank (15) and a single-port sealing device (19). The double-port sealing system comprises a double-port sealing device (7), a sealing device water injection pipe (8), a sealing device water injection pump (9) and a main water tank (10). The water injection pipeline (12) is connected to a single-hole sealing device (19); The double-port hole sealer (7) is connected to a hole sealer water injection pipe (8); The pressure monitoring system comprises a pressure sensor (17) and a pressure detection station (18), and the pressure detection station (18) is connected to the pressure sensor (17) via a signal cable.

3. A blasting permeability enhancement water injection system according to claim 2, characterized in that: The double-port hole sealer (7) comprises a water injection port, a rubber capsule and a water outlet, and the water injection port comprises a drilling water injection port and a hole sealer water injection port.

4. The blasting permeability enhancement water injection system according to claim 3, characterized in that: The rubber bladder is made of modified rubber.

5. The blasting permeability enhancement water injection system according to claim 4, characterized in that: The drilled water injection port is made of stainless steel.

6. The blasting permeability enhancement water injection system according to claim 2, characterized in that: The water injection operation table (13) is arranged on a side of the water injection pipeline (12) close to the water pump (14).

7. The blasting permeability enhancement water injection system according to claim 2, characterized in that: The blasting system also includes a safety rope (6).

8. The blasting permeability enhancement water injection system according to claim 2, characterized in that: A pressure gauge and a water injection valve are arranged in the water injection operating table (13).

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