Automatic dust removal and blowout prevention system and method for pneumatic directional drilling in underground coal mine

Abstract

The application discloses a kind of coal mine underground pneumatic directional drilling automatic dust removal blowout prevention system and method, the system includes wind guide dust isolation tent, dust removal spray component, extraction dust removal fan, screen mesh wet dust removal cylinder, dust removal pool, orifice dust isolation sealing air bag, orifice blowout prevention air bag, flow sensor, dust sensor and methane concentration sensor;Wind guide dust isolation tent and orifice dust isolation sealing air bag are used to realize the separation of air flow and the sealing of dust;While wind guide dust isolation tent and orifice dust isolation sealing air bag realize the centralized sealing of dust in hole, facilitate centralized dust removal;Dust removal spray component, screen mesh wet dust removal cylinder and dust removal pool three-stage dust removal will be completely treated dust;Orifice blowout prevention air bag can realize the plugging of gas channel in hole, prevent gas overrun caused by spray hole.The application can significantly improve the dust treatment effect and blowout prevention effect of coal mine underground pneumatic directional drilling site, greatly improve the working environment, and protect the physical and mental health of workers.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coal mine drilling, and relates to a gas-driven directional drilling construction hole orifice dust removal and blowout prevention system and method, in particular to an automatic dust removal and blowout prevention system and method for gas-driven directional drilling in a coal mine underground. BACKGROUND

[0002] In recent years, gas-driven directional drilling technology has begun to be widely applied in coal mine underground gas control. On the one hand, the controllable trajectory of directional drilling can realize accurate control of the drilling trajectory and effectively avoid the gas control blank zone. On the other hand, the technology uses high-pressure gas as the driving medium and cooling and deslagging medium of the gas-driven screw drill, has the characteristics of small disturbance to the drilling hole wall, and can effectively improve the drilling depth and hole completion rate in the gas control of broken soft coal seams. At present, it has become the most effective technical means for drilling hole completion in the gas control of broken soft coal seams.

[0003] The gas-driven directional drilling technology uses high-pressure gas as the driving and deslagging medium, which leads to serious dust pollution at the drilling construction site. If not properly handled, it will seriously affect the physical and mental health of the workers, and also restricts the popularization and application of the technology. In recent years, domestic and foreign scholars have also made a lot of research on dust treatment, and have developed various types of dust removal devices. Among them, the orifice ejection flow type dust removal device is the most widely used. This device forms a negative pressure through the jet flow, sucks the dust discharged from the hole into the dust collector, and then uses ventilation and water mist for dust removal. Although it can handle a part of the dust, it still has the following problems: first, the dust removal negative pressure is limited, and the negative pressure suction force is insufficient, which cannot meet the requirements; second, the dust removal device has poor sealing performance, especially at the connection between the dust removal device and the drill pipe and at the deslagging port, which is easy to overflow a large amount of dust; third, the dust removal device needs to be connected to the suction negative pressure, which is easy to cause blockage of the negative pressure pipeline due to the entry of coal dust and water.

[0004] During the gas-driven directional drilling process, on the one hand, a large amount of gas is often discharged along with the deslagging gas. If the hole orifice blowout prevention is not in place, it is easy to cause gas overrun accidents. On the other hand, for coal seams with high gas pressure, the release of ground pressure and gas pressure during the construction process will cause instantaneous blowout. If not properly handled, it is also easy to cause gas overrun accidents. The existing blowout prevention device has the problems of poor sealing effect, and part of the gas still overflows when blowout occurs. SUMMARY

[0005] In view of the problems in the prior art, the present application aims to provide an automatic dust removal and blowout prevention system and method for gas-driven directional drilling in a coal mine underground, to solve the problems of serious dust pollution, unsatisfactory dust removal effect, poor sealing effect of the existing blowout prevention device, and inability to effectively prevent blowout, which easily causes gas overrun accidents, etc.

[0006] To solve the above technical problems, the present application adopts the following technical solutions to achieve:

[0007] The automatic dust removal and blowout prevention system for pneumatic directional drilling in underground coal mine comprises a wind-guiding and dust-separating curtain, a dust-removal spray assembly, an extraction dust-removal fan, a mesh wet dust-removal cylinder, a dust-removal pool, a borehole dust-separation sealing air bag, a borehole blowout prevention air bag, a flow sensor, a dust sensor and a methane concentration sensor.

[0008] The wind-guiding and dust-separating curtain is arranged in the roadway, and the upper and lower edges thereof are tightly attached to the roof and floor of the roadway, respectively, to form a wind-guiding and dust-removal channel together with the side wall on which the borehole is located. The drill rod can pass through the wind-guiding and dust-separating curtain and work.

[0009] The dust-removal spray assembly has multiple groups and is arranged in the wind-guiding and dust-removal channel.

[0010] The extraction dust-removal fan is arranged on the downwind side of the dust-removal spray assembly, and the dust collection cover of the extraction dust-removal fan covers the entire wind passage cross section of the wind-guiding and dust-removal channel.

[0011] The mesh wet dust-removal cylinder is connected to the outlet of the extraction dust-removal fan, and the dust-removal pool is arranged at the outlet of the mesh wet dust-removal cylinder.

[0012] The borehole dust-separation sealing air bag and the borehole blowout prevention air bag are arranged in the annulus between the drill rod and the borehole pipe, respectively, and the borehole dust-separation sealing air bag is arranged at the port of the borehole pipe, and the borehole blowout prevention air bag is arranged inside the borehole pipe.

[0013] The flow sensor, the dust sensor and the methane concentration sensor are arranged in the wind-guiding and dust-removal channel.

[0014] The present application also comprises the following technical features:

[0015] Optionally, the wind-guiding and dust-separating curtain is made of anti-static and air-tight material.

[0016] The position of the front air inlet of the wind-guiding and dust-separating curtain is adjustable to adjust the opening degree of the air inlet.

[0017] Optionally, the dust-removal spray assembly has four groups, which are installed in sequence along the wind direction, one group is arranged on the upwind side of the borehole, and the other three groups are arranged in sequence on the downwind side of the borehole.

[0018] Optionally, the dust collecting hood of the extraction dust removal fan is trumpet-shaped; the upper part of the dust collecting hood is closely attached to the roof of the roadway, the lower part is closely attached to the floor of the roadway, and the left and right parts are closely attached to the sidewall of the roadway and the air guide dust separating curtain respectively.

[0019] Optionally, the screen mesh wet dust removal cylinder comprises a cylinder body, a central rotating shaft, a spiral dust catching screen and a spray head; the two ends of the cylinder body are respectively connected to the outlet of the extraction dust removal fan and the dust removal pool, the central rotating shaft is coaxially arranged in the cylinder body, the spiral dust catching screen is arranged on the central rotating shaft, a plurality of screen meshes are arranged on the spiral dust catching screen, the diameter of the screen meshes is 1mm-3mm, and the spray head is arranged on the upper part of the inner wall of the cylinder body.

[0020] Optionally, the flow sensor is arranged at the air inlet of the air guide dust removal channel to monitor the air volume at the air inlet; the dust sensor and the methane concentration sensor are arranged at the downwind side of the orifice to monitor the dust concentration and the methane concentration at the downwind side of the borehole respectively.

[0021] Optionally, the orifice dust separating sealing air bag and the orifice blowout preventing air bag are both connected to the inflation pipeline and can be filled between the drill pipe and the orifice pipe after inflation and expansion; the orifice pipe is arranged in the borehole and the end thereof extends out of the borehole, two annular grooves are arranged on the inner wall of the orifice pipe, and the orifice dust separating sealing air bag and the orifice blowout preventing air bag are respectively arranged in the two annular grooves to axially position the orifice dust separating sealing air bag and the orifice blowout preventing air bag.

[0022] A dust removal method of the underground pneumatic directional drilling automatic dust removal and blowout prevention system of the coal mine comprises the following steps:

[0023] Step a1: the air guide dust separating curtain and the orifice dust separating sealing air bag are used to separate the air inlet of the roadway and seal the dust at the orifice of the borehole; the air inlet in the roadway is divided into two parts by the air guide dust separating curtain, one part of the air enters the air guide dust removal channel on the inner side of the air guide dust separating curtain to be dust removed, and the other part of the air enters the roadway to supply air to other operation points in the roadway; the orifice dust separating sealing air bag is inflated to seal the gap between the orifice pipe and the drill pipe, so that the dust is sealed; when the flow monitored by the flow sensor is less than a set value Q1, the air guide dust separating curtain is automatically adjusted to increase the opening degree; when the flow monitored by the flow sensor is equal to the set value Q1, the air guide dust separating curtain is automatically adjusted to 0°; and when the flow monitored by the flow sensor is greater than the set value Q1, the air guide dust separating curtain is automatically adjusted to decrease the opening degree.

[0024] Step a2: when the dust sensor at the orifice monitors that the dust concentration is greater than a set value Q2, the water and air supply pipeline is automatically opened to supply water and air to the dust removal spray head of the dust removal spray assembly and form a spray, and the dust returned from the orifice is first subjected to primary dust removal by the dust removal spray; when the dust sensor at the orifice monitors that the dust concentration is less than the set value Q2, the water and air supply pipeline is automatically closed.

[0025] Step a3: when the dust concentration monitored by the dust sensor at the orifice is greater than the set value Q2, the extraction dust removal fan is automatically started, and the extraction dust removal fan forms a suction negative pressure to suck the dust after the dust removal spray treatment into the extraction dust removal fan through the horn-shaped dust collecting cover; when the dust concentration monitored by the dust sensor at the orifice is less than the set value Q2, the extraction dust removal fan is automatically stopped;

[0026] Step a4: the dust flowing through the extraction dust removal fan enters the screen mesh wet dust removal cylinder through the pipeline, under the flow effect of the air flow, the spiral dust catching screen of the screen mesh wet dust removal cylinder rotates, the dust passes through the screen mesh of the spiral dust catching screen and the spray jetted out by the spray head, and secondary dust removal is completed.

[0027] Step a5: the dust after the treatment of the screen mesh wet dust removal cylinder enters the dust removal pool through the pipeline, under the wetting effect of the water in the dust removal pool, the dust is deposited into the water, and the gas overflows the water surface into the roadway, and tertiary dust removal is completed.

[0028] A kind of said coal mine underground pneumatic directional drilling automatic dust removal blowout prevention system of the method for preventing blowout, comprising the following steps:

[0029] Step b1: connect the drilling tool to normally drill, open the air supply pipeline to supply air to the drill pipe, and the compressed air enters the hole bottom through the through hole in the drill pipe to drive the screw rod drilling tool to rotate the drill bit to crush rocks and then returns from the annulus between the hole wall and the drill pipe.

[0030] Step b2: when the methane concentration sensor at the downwind side of the orifice monitors that the methane concentration is greater than the set value Q3, the inflation pipeline is opened and inflated into the orifice blowout prevention air bag, until the orifice blowout prevention air bag is completely inflated, the air bag seals the gap between the orifice pipe and the drill pipe to prevent gas from being sprayed out to cause gas overrun.

[0031] Step b3: when the methane concentration sensor at the downwind side of the orifice monitors that the methane concentration is less than the set value Q3, the inflation pipeline is closed, the pressure relief pipeline is opened, the orifice blowout prevention air bag is relieved, the orifice blowout prevention air bag is contracted, and the drill cuttings and gas can be normally discharged through the gap between the orifice pipe and the drill pipe.

[0032] Compared with the prior art, the present application has the following technical effects:

[0033] The application adopts the air guide dust isolation curtain and the orifice dust isolation sealing air bag to realize the separation of air flow and the sealing of dust, divides fresh air into two parts, one part is used for dust removal, and the other part is used for supplying fresh air to the downwind side, meanwhile, the air guide dust isolation curtain and the orifice dust isolation sealing air bag realize the centralized sealing of dust in the orifice, which is convenient for centralized dust removal; after four groups of dust removal spray, mesh wet type dust removal cylinder and dust removal pool three-stage dust removal, the dust treatment is complete. The orifice anti-blowing air bag effectively prevents gas over-limit caused by the blowhole. The air inlet angle of the air guide dust isolation curtain, the dust removal spray and the dust removal machine can be automatically started and stopped according to the set parameters, the automatic dust removal and blowout prevention are realized, the dust removal efficiency is provided, the labor intensity is reduced, and the water resource is saved.

[0034] The system and method can significantly improve the dust treatment effect and blowout prevention effect of the pneumatic directional drilling site underground coal mine, greatly improve the site operation environment, and protect the physical and mental health of the operation personnel. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is a whole schematic diagram of the system of the application;

[0036] Figure 2 It is a structure schematic diagram of the dust removal spray assembly of the application;

[0037] Figure 3 It is a front view of the dust collecting cover of the application;

[0038] Figure 4 It is a side view of the dust collecting cover of the application;

[0039] Figure 5 It is a top view of the dust collecting cover of the application;

[0040] Figure 6 It is a structure schematic diagram of the mesh wet type dust removal cylinder of the application.

[0041] The meanings of various reference numerals in the drawings are as follows:

[0042] 1. air guide dust isolation curtain, 2. dust removal spray assembly, 3. extracted dust removal fan, 4. mesh wet type dust removal cylinder, 5. dust removal pool, 6. orifice dust isolation sealing air bag, 7. orifice anti-blowing air bag, 8. flow sensor, 9. dust sensor, 10. methane concentration sensor; 11. rotating shaft; 21. dust removal spray head, 22. dust removal curtain; 31. dust collecting cover; 41. cylinder body, 42. central rotating shaft, 43. spiral dust collecting screen, 44. spray head, 45. mesh. DETAILED DESCRIPTION

[0043] The following gives a specific embodiment of the application, and it should be noted that the application is not limited to the following specific embodiment, and any equivalent transformation based on the technical scheme of the application falls within the protection scope of the application.

[0044] Example 1:

[0045] like Figures 1 to 6 As shown, this embodiment provides an automatic dust removal and blowout prevention system for pneumatic directional drilling in coal mines, including an air guide dust screening tent 1, a dust removal spray assembly 2, an exhaust dust removal fan 3, a mesh wet dust removal cylinder 4, a dust removal pool 5, an orifice dust isolation sealing airbag 6, an orifice anti-blowout bag 7, a flow sensor 8, a dust sensor 9 and a methane concentration sensor 10.

[0046] The air-guiding dust-proof tent 1 is set in the tunnel, and its upper and lower edges are respectively close to the top and bottom plates of the tunnel, so as to form an air-guiding dust-removing channel with the side wall where the drill hole is located; the air-guiding dust-proof tent 1 can separate the main drilling rig outside the air-guiding dust-removing channel to isolate dust and improve the working environment of the main drilling rig staff; the drill rod can operate after passing through the air-guiding dust-proof tent 1.

[0047] There are multiple groups of dust removal spray components 2, which are arranged at intervals in the air guide and dust removal channel.

[0048] The extraction type dust removal fan 3 is arranged on the downwind side of the dust removal spray assembly 2, and the dust collecting cover 31 of the extraction type dust removal fan 3 covers the entire wind cross section of the air guide and dust removal channel.

[0049] The mesh wet dust removal cylinder 4 is connected to the outlet of the extraction dust removal fan 3; the dust removal pool 5 is arranged at the outlet of the mesh wet dust removal cylinder 4.

[0050] The orifice dust-proof sealing airbag 6 and the orifice anti-air-jet bag 7 are respectively arranged in the annulus between the drill pipe and the orifice pipe, and the orifice dust-proof sealing airbag 6 is located at the end of the orifice pipe, and the orifice anti-air-jet bag 7 is located inside the orifice pipe.

[0051] The flow sensor 8, the dust sensor 9 and the methane concentration sensor 10 are all arranged in the air guide and dust removal channel.

[0052] The upwind side and leeward side of each device / component / opening involved in this embodiment respectively refer to the two sides of the device / component / opening, the side close to the air inlet of the air guide and dust removal channel is the upwind side of the device / component / opening, and the side close to the air outlet of the air guide and dust removal channel is the leeward side of the device / component / opening.

[0053] The air guide and dust isolation tent 1 is made of anti-static and airtight material.

[0054] The front air inlet of the air guide and dust isolation curtain 1 is adjustable in position to adjust the opening degree of the air inlet of the air guide and dust isolation curtain 1; a rotating shaft 11 perpendicular to the roof and floor of the roadway is arranged at the front air inlet of the air guide and dust isolation curtain 1, and the front part of the air guide and dust isolation curtain 1 can rotate around the rotating shaft 11 to adjust the angle of the air inlet in the range of -30° to 30°; specifically, when the front part of the air guide and dust isolation curtain is in the same plane as the whole air guide and dust isolation curtain, the angle of the air inlet is 0°, when the front part of the air guide and dust isolation curtain is rotated by 30° around the rotating shaft to the side of the drilling hole, the angle of the air inlet is -30°, and when the front part of the air guide and dust isolation curtain is rotated by 30° around the rotating shaft to the side opposite to the drilling hole, the angle of the air inlet is 30°. When the monitoring value of the flow sensor is less than the set value Q1, the air inlet angle is automatically adjusted to 30°; when the monitoring value of the flow sensor is equal to the set value Q1, the air inlet angle is automatically adjusted to 0°; and when the monitoring value of the flow sensor is greater than the set value Q1, the air inlet angle is automatically adjusted to -30°.

[0055] The dust removal spray assembly 2 has four groups, which are installed in sequence along the direction of the airflow, one group is arranged on the upwind side of the orifice, and the other three groups are arranged in sequence and spaced on the downwind side of the orifice; the dust removal spray assembly 2 includes a plurality of dust removal spray heads 21 suspended from the roof of the roadway and a dust removal curtain 22, and the dust removal curtain 22 can cover the entire air guide and dust removal passage. The plurality of dust removal spray heads 21 are arranged at intervals, and the direction of the dust removal spray head 21 can be adjusted. The number of dust removal spray heads in each group is 3-5, and the angle between the direction of the water mist sprayed by the spray head and the direction of the dust flow is always 90°-180°; when the monitoring value of the dust sensor is less than the set value Q2, the dust removal spray head is automatically closed; and when the monitoring value of the dust sensor is greater than the set value Q2, the dust removal spray head is automatically opened for dust removal.

[0056] The dust collection cover 31 of the extraction type dust removal fan 3 is in the shape of a horn; the upper part of the dust collection cover 31 is closely attached to the roof of the roadway, the lower part is closely attached to the floor of the roadway, and the left and right parts are closely attached to the side of the roadway and the air guide and dust isolation curtain 1 respectively. A suction negative pressure is formed by the dust removal fan to suck the dust on the upper side of the dust removal fan into the dust removal fan. When the monitoring value of the dust sensor is less than the set value Q2, the extraction type dust removal fan is automatically closed; and when the monitoring value of the dust sensor is greater than the set value Q2, the extraction type dust removal fan is automatically opened.

[0057] The screen mesh wet dust removal cylinder 4 comprises a cylinder body 41, a central rotating shaft 42, a spiral dust collection screen 43 and a spray head 44. The cylinder body 41 is connected to the outlet of the dust removal fan 3 and the dust removal pool 5 respectively. The central rotating shaft 42 is coaxially arranged in the cylinder body 41. The spiral dust collection screen 43 is arranged on the central rotating shaft 42. The spiral dust collection screen 43 is provided with a plurality of screen meshes 45 with a diameter of 1mm-3mm. The spray head 44 is arranged on the upper inner wall of the cylinder body 41. A plurality of spray heads 44 are arranged along the axial direction of the cylinder body 41. The spray head is automatically started and stopped according to the on-site dust concentration. When the dust sensor monitoring value is greater than the set value Q2, the spray head is automatically opened for dust removal. When the dust sensor monitoring value is less than the set value Q2, the spray head is automatically closed. The dust removal screen can automatically rotate under the blowing of the air flow.

[0058] The flow sensor 8 is arranged at the air inlet of the air guide dust removal channel to monitor the air volume at the air inlet. The dust sensor 9 and the methane concentration sensor 10 are arranged at the downwind side of the orifice to monitor the downwind side dust concentration and methane concentration of the borehole respectively. More specifically, the flow sensor, the dust sensor and the methane concentration sensor can be hung on the roadway roof or installed in other ways in the air guide dust removal channel to achieve the effect of the present scheme.

[0059] The dust removal pool is filled with water. The dust removed by the screen mesh wet dust removal cylinder is connected to the bottom of the dust removal pool through a pipeline. The dust is completely removed by being soaked in water and remaining in the dust removal pool. The clean gas flows out of the dust removal pool to the roadway, thereby realizing complete dust removal.

[0060] The orifice dust isolation sealing air bag 6 and the orifice blowout prevention air bag 7 are connected to the inflation pipeline and can be inflated to fill the space between the drill pipe and the orifice pipe. The orifice pipe is arranged in the borehole and extends out of the borehole. Two annular grooves are arranged on the inner wall of the orifice pipe. The orifice dust isolation sealing air bag 6 and the orifice blowout prevention air bag 7 are arranged in the two annular grooves respectively to axially position the orifice dust isolation sealing air bag 6 and the orifice blowout prevention air bag 7. When the methane concentration sensor monitoring value is lower than the set value Q3, the orifice blowout prevention air bag is in a contracted state. When the methane concentration sensor monitoring value is greater than the set value Q3, the orifice blowout prevention air bag is in an inflated state.

[0061] Embodiment 2

[0062] The present embodiment provides a dust removal method of the coal mine underground pneumatic directional drilling automatic dust removal and blowout prevention system in embodiment 1, comprising the following steps:

[0063] Step a1: the air guide dust separation curtain and the orifice dust sealing air bag are used to realize the separation of the air inlet of the roadway and the sealing of the dust of the drilling orifice; the air inlet in the roadway is divided into two parts by the air guide dust separation curtain, one part of the air enters the air guide dust removal channel inside the air guide dust separation curtain for dust removal, and the other part of the air enters the roadway to meet the air supply of other operation points in the roadway; the orifice dust sealing air bag is inflated to realize the sealing of the gap between the orifice pipe and the drill pipe, so that the dust is sealed; when the flow monitored by the flow sensor is less than the set value Q1, the air guide dust separation curtain is automatically adjusted to increase the opening degree, and the air guide dust separation curtain is automatically adjusted to 30°; when the flow monitored by the flow sensor is equal to the set value Q1, the air guide dust separation curtain is automatically adjusted to 0°; when the flow monitored by the flow sensor is greater than the set value Q1, the air guide dust separation curtain is automatically adjusted to reduce the opening degree, and the air guide dust separation curtain is automatically adjusted to -30°;

[0064] Step a2: when the dust sensor at the orifice monitors that the dust concentration is greater than the set value Q2, the water and air supply pipeline is automatically opened to supply water and air to the dust removal spray head of the dust removal spray assembly and the spray head in the mesh wet dust removal cylinder, and the dust returned from the orifice is first subjected to primary dust removal by the dust removal spray; when the dust sensor at the orifice monitors that the dust concentration is less than the set value Q2, the water and air supply pipeline is automatically closed.

[0065] Step a3: when the dust sensor at the orifice monitors that the dust concentration is greater than the set value Q2, the extraction type dust removal fan is automatically started, and the extraction type dust removal fan forms a suction negative pressure to suck the dust treated by the dust removal spray into the extraction type dust removal fan through the horn-shaped dust collection cover; when the dust sensor at the orifice monitors that the dust concentration is less than the set value Q2, the extraction type dust removal fan is automatically stopped.

[0066] Step a4: the dust flowing through the extraction type dust removal fan enters the mesh wet dust removal cylinder through the pipeline, and under the flow of the air flow, the spiral dust collection screen of the mesh wet dust removal cylinder rotates, the dust passes through the mesh of the spiral dust collection screen, and the spray jetted out by the spray head, so that the secondary dust removal is completed.

[0067] Step a5: the dust treated by the mesh wet dust removal cylinder is introduced into the dust removal pool through the pipeline, and under the action of the water in the dust removal pool, the dust is deposited into the water, and the gas overflows the water surface into the roadway, so that the tertiary dust removal is completed.

[0068] Embodiment 3

[0069] The embodiment provides a blowout prevention method of the automatic dust removal blowout prevention system for the pneumatic directional drilling in the coal mine underground in embodiment 1, and the method comprises the following steps.

[0070] Step b1: the drilling tool is connected for normal drilling, the air supply pipeline is opened to supply air to the drill pipe, the compressed air enters the hole bottom through the through hole in the drill pipe to drive the screw drill tool to rotate the drill bit to crush rocks, and then returns from the annulus between the hole wall and the drill pipe.

[0071] Step b2: when the methane concentration sensor on the downwind side of the orifice monitors the methane concentration greater than the set value Q3, the inflation pipeline is opened and inflated into the orifice blowout preventer airbag, until the orifice blowout preventer airbag is fully inflated, the airbag seals the gap between the orifice pipe and the drill pipe, preventing gas from being sprayed out to cause gas overrun;

[0072] Step b3: when the methane concentration sensor on the downwind side of the orifice monitors the methane concentration less than the set value Q3, the inflation pipeline is closed, the pressure relief pipeline is opened, the orifice blowout preventer airbag is relieved, the orifice blowout preventer airbag is contracted, and the drill cuttings and gas can be normally discharged through the gap between the orifice pipe and the drill pipe.

[0073] The present application uses the wind guide dust separation curtain and the orifice dust separation sealing airbag to realize the separation of wind flow and the sealing of dust, divides the fresh wind into two parts, one part is used for dust removal, and the other part is used for supplying fresh wind to the downwind side, and the wind guide dust separation curtain and the orifice dust separation sealing airbag realize the centralized sealing of the dust in the hole, which is convenient for centralized dust removal; after four groups of dust removal spraying, mesh wet dust removal cylinder and dust removal pool three-stage dust removal, the dust treatment is complete. The orifice blowout preventer airbag effectively prevents gas overrun caused by the orifice. The air inlet angle of the wind guide dust separation curtain, the dust removal spraying and the dust removal machine can be automatically started and stopped according to the set parameters, realizing automatic dust removal and blowout prevention, providing dust removal efficiency, reducing labor intensity and saving water resources. In summary, the system and method of the present application can significantly improve the dust treatment effect and blowout prevention effect of the pneumatic directional drilling site in the coal mine underground, greatly improve the site operation environment, and protect the physical and mental health of the operation personnel.

[0074] The preferred embodiments of the present application are described in detail above in combination with the drawings, but the present application is not limited to the specific details in the above-described embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application.

[0075] In addition, it should be noted that various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, various possible combinations are not described again by the present application.

[0076] In addition, various different embodiments of the present application can also be combined in any manner, as long as they do not deviate from the idea of the present application, and they should also be considered as disclosed by the present application.

Claims

1. A dust removal method of an automatic dust removal blowout prevention system of a pneumatic directional drilling in a coal mine underground, characterized in that, The automatic dust removal and blowout prevention system for pneumatic directional drilling in coal mine underground comprises a wind guide and dust separation curtain (1), a dust removal and spraying assembly (2), an extracted dust removal fan (3), a mesh wet dust removal cylinder (4), a dust removal pool (5), a borehole dust separation and sealing air bag (6), a borehole blowout prevention air bag (7), a flow sensor (8), a dust sensor (9) and a methane concentration sensor (10); The wind guide and dust separation curtain (1) is arranged in the roadway, and the upper and lower edges thereof are tightly attached to the roof and floor of the roadway respectively to form a wind guide and dust removal channel with the side wall of the borehole; the wind guide and dust separation curtain (1) can separate the drilling machine from the wind guide and dust removal channel to separate dust; the drill rod can pass through the wind guide and dust separation curtain (1) to work; The dust removal and spraying assembly (2) has multiple groups and is arranged in the wind guide and dust removal channel at intervals; The extracted dust removal fan (3) is arranged on the downwind side of the dust removal and spraying assembly (2), and the dust collection cover (31) of the extracted dust removal fan (3) covers the entire wind passage cross section of the wind guide and dust removal channel; The mesh wet dust removal cylinder (4) is connected with the outlet of the extracted dust removal fan (3); and the dust removal pool (5) is arranged at the outlet of the mesh wet dust removal cylinder (4); The borehole dust separation and sealing air bag (6) and the borehole blowout prevention air bag (7) are both arranged in the annulus between the drill rod and the borehole, and the borehole dust separation and sealing air bag (6) is arranged at the port of the borehole, and the borehole blowout prevention air bag (7) is arranged inside the borehole; The flow sensor (8), the dust sensor (9) and the methane concentration sensor (10) are all arranged in the wind guide and dust removal channel; The method comprises the following steps: Step a1: the wind guide and dust separation curtain and the borehole dust separation and sealing air bag are used to separate the air inlet of the roadway and seal the dust of the borehole; the air inlet in the roadway is divided into two parts by the wind guide and dust separation curtain, one part of the air enters the wind guide and dust removal channel on the inside of the wind guide and dust separation curtain to remove dust, and the other part of the air enters the roadway to supply air to other working points in the roadway; the borehole dust separation and sealing air bag is inflated to seal the gap between the borehole and the drill rod, so that the dust is sealed; when the flow monitored by the flow sensor is less than the set value Q1, the wind guide and dust separation curtain is automatically adjusted to increase the opening; when the flow monitored by the flow sensor is equal to the set value Q1, the wind guide and dust separation curtain is automatically adjusted to 0°; when the flow monitored by the flow sensor is greater than the set value Q1, the wind guide and dust separation curtain is automatically adjusted to decrease the opening; Step a2: when the dust concentration monitored by the dust sensor at the borehole is greater than the set value Q2, the water and air supply pipeline is automatically opened to supply water and air to the dust removal and spraying assembly, and the dust returning from the borehole first passes through the dust removal and spraying assembly to complete primary dust removal; when the dust concentration monitored by the dust sensor at the borehole is less than the set value Q2, the water and air supply pipeline is automatically closed; Step a3: when the dust concentration monitored by the dust sensor at the borehole is greater than the set value Q2, the extracted dust removal fan is automatically started, and the extracted dust removal fan forms a suction negative pressure to suck the dust treated by the dust removal and spraying assembly into the extracted dust removal fan through the horn-shaped dust collection cover; when the dust concentration monitored by the dust sensor at the borehole is less than the set value Q2, the extracted dust removal fan is automatically stopped. Step a4: the dust flowing through the extraction dust fan enters the screen mesh wet dust removal cylinder through the pipeline. Under the flow of the air flow, the spiral dust collection screen of the screen mesh wet dust removal cylinder rotates. The dust passes through the screen mesh of the spiral dust collection screen and the spray jetted out by the spray head, completing the secondary dust removal. Step a5: the dust treated by the screen mesh wet dust removal cylinder enters the dust removal pool through the pipeline. Under the water infiltration in the dust removal pool, the dust is deposited into the water, and the gas overflows the water surface into the roadway, completing the tertiary dust removal.

2. The dust removal method of the automatic dust removal and blowout prevention system for the underground pneumatic directional drilling of coal mines according to claim 1, characterized in that, The air guide dust isolation curtain (1) is made of anti-static and air-tight material. The front air inlet of the air guide dust isolation curtain (1) is adjustable to adjust the opening of the air inlet of the air guide dust isolation curtain (1). A rotating shaft (11) perpendicular to the roof and floor of the roadway is arranged at the front air inlet of the air guide dust isolation curtain (1). The front part of the air guide dust isolation curtain (1) can rotate around the rotating shaft (11) to adjust the angle of the air inlet within the range of -30° to 30°.

3. The dust removal method of the automatic dust removal and blowout prevention system for the underground pneumatic directional drilling of coal mines according to claim 1, characterized in that, The dust removal spray assembly (2) has four groups, which are installed in sequence along the direction of the air flow. One group is arranged on the upwind side of the orifice, and the other three groups are arranged in sequence on the downwind side of the orifice. The dust removal spray assembly (2) includes a plurality of dust removal spray heads (21) hung on the roof of the roadway and a dust removal curtain (22). The dust removal curtain (22) can cover the entire air flow cross section of the air guide dust removal channel. The plurality of dust removal spray heads (21) are arranged at intervals, and the direction of the dust removal spray head (21) is adjustable.

4. The dust control method of the automatic dust control and blowout prevention system for the pneumatic directional drilling in underground coal mines according to claim 1, characterized in that, The dust collection cover (31) of the extraction dust fan (3) is in the shape of a horn. The upper part of the dust collection cover (31) is closely attached to the roof of the roadway, the lower part is closely attached to the floor of the roadway, and the left and right parts are closely attached to the side walls of the roadway and the air guide dust isolation curtain (1), respectively.

5. The dust control method of the underground coal mine pneumatic directional drilling automatic dust control and blowout prevention system of claim 1, wherein, The screen mesh wet dust removal cylinder (4) includes a cylinder body (41), a central rotating shaft (42), a spiral dust collection screen (43), and a spray head (44). The two ends of the cylinder body (41) are respectively connected to the outlet of the extraction dust fan (3) and the dust removal pool (5). The central rotating shaft (42) is coaxially arranged in the cylinder body (41). The spiral dust collection screen (43) is arranged on the central rotating shaft (42). The spiral dust collection screen (43) is provided with a plurality of screen meshes (45) with a diameter of 1mm to 3mm. The spray head (44) is arranged on the upper inner wall of the cylinder body (41). A plurality of spray heads (44) are arranged at intervals along the axial direction of the cylinder body (41).

6. The dust control method of the underground coal mine pneumatic directional drilling automatic dust control and blowout prevention system of claim 1, wherein, The flow sensor (8) is arranged at the air inlet of the air guide dust removal channel to monitor the air flow at the air inlet. The dust sensor (9) and the methane concentration sensor (10) are arranged on the downwind side of the orifice to monitor the dust concentration and methane concentration on the downwind side of the borehole, respectively.

7. The dust control method of the underground coal mine pneumatic directional drilling automatic dust control and blowout prevention system of claim 1, wherein, The orifice dust isolation sealing air bag (6) and the orifice blowout prevention air bag (7) are connected to the inflation pipeline and can be filled between the drill pipe and the orifice pipe after inflation. The orifice pipe is arranged in the borehole and extends out of the borehole. Two annular grooves are arranged on the inner wall of the orifice pipe. The orifice dust isolation sealing air bag (6) and the orifice blowout prevention air bag (7) are respectively arranged in the two annular grooves to axially position the orifice dust isolation sealing air bag (6) and the orifice blowout prevention air bag (7).

8. A blowout prevention method for an underground coal mine pneumatic directional drilling automatic dust removal blowout prevention system, characterized in that, The method is implemented by the dust removal method of the automatic dust removal blowout prevention system for pneumatic directional drilling in underground coal mine according to any one of claims 1 to 7, and comprises the following steps: Step b1: connecting drilling tools for normal drilling, opening the air supply pipeline to supply air into the drill pipe, and driving the screw rod drilling tool to rotate the drill bit to crush rocks, and then returning the air from the annulus between the borehole wall and the drill pipe; Step b2: when the methane concentration sensor on the downwind side of the borehole opening monitors that the methane concentration is greater than the set value Q3, the inflation pipeline is opened and inflated into the borehole opening blowout prevention air bag, until the borehole opening blowout prevention air bag is fully inflated, the air bag seals the gap between the borehole opening pipe and the drill pipe, preventing gas from being sprayed out to cause gas overrun; Step b3: when the methane concentration sensor on the downwind side of the borehole opening monitors that the methane concentration is less than the set value Q3, the inflation pipeline is closed, the pressure relief pipeline is opened, the borehole opening blowout prevention air bag is relieved, the borehole opening blowout prevention air bag is contracted, and the drill cuttings and gas can be normally discharged through the gap between the borehole opening pipe and the drill pipe.

Images