Dust control and slag removal system and method for soft coal seams

Abstract

This invention provides a dust control and slag removal system and method for soft coal seams, comprising an annular sealing assembly, a dust removal assembly, a first conveying pipe, a connecting assembly, a negative pressure suction assembly, a second conveying pipe, a gas-solid separator, a foam generator, and a screw conveyor. At least a portion of the annular sealing assembly is disposed within a borehole in the coal seam and is sealed to the inner wall of the borehole. The interior of the annular sealing assembly is connected to the interior of the borehole and the dust removal assembly. The lower part of the dust removal assembly is connected to one end of the first conveying pipe, and the other end of the first conveying pipe is connected to the outside. The connecting assembly is connected to one end of the dust removal assembly, the negative pressure suction assembly, and the second conveying pipe. The technical solution provided by this invention can solve the problems of existing soft coal seam dust control and slag removal technologies, such as the inability to effectively reduce the dust and gas concentration at the borehole opening, low efficiency in solid drill cuttings removal, and the potential for gas blowouts.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, and more specifically, to a dust control and slag removal system and method for soft coal seams. Background Technology

[0002] In the coal mining industry, especially in high-pressure, high-flow-rate gas drilling operations in soft, fractured coal seams, dust control and slag removal are crucial for ensuring coal mine gas management and safe mining. Currently, the industry's commonly used dust control and slag removal technologies mainly include wellhead sealing to prevent blowouts, jet or spray dust suppression, and drill cuttings collection and transportation.

[0003] Existing wellhead sealing blowout prevention technologies aim to prevent the direct leakage of gas-solid mixtures by using rubber gaskets on the drill pipe at the wellhead, thereby reducing the impact of dust and gas on the working environment. However, when faced with the dynamic changes during the rotation of specially designed drill pipes for soft coal, such as grooved drill pipes or triangular drill pipes, traditional rubber gaskets are prone to wear, leading to a decrease in sealing effectiveness. Especially when drilling uses high-pressure (≥1.2MPa) high-flow-rate gas, the dust concentration at the wellhead remains high, affecting the safety and health of the workers.

[0004] Existing jet dust removal and spray dust removal technologies use spray devices around the borehole or near the drill rod to spray water mist into the air to capture dust particles. However, in high-pressure, high-speed airflow drilling scenarios, the water mist is easily dispersed due to the high wind speed, resulting in unsatisfactory dust removal effects and failing to meet the dust control requirements of high-pressure, high-flow-rate gas drilling.

[0005] Existing technologies for treating drill cuttings primarily focus on the use of slag collection boxes. These boxes are equipped with agitators and high-pressure sprayers to moisten the cuttings and prevent dust generation. The cuttings are then transported to a vibrating screen via a slag-water transfer pump and pipelines to achieve solid-liquid separation. However, this method has limited applicability to different borehole angles and complex coal seam conditions. In particular, when the borehole is inclined or has a large dip angle, the removal of cuttings may be obstructed, leading to poor slag discharge and affecting continuous and efficient drilling operations.

[0006] In addition, existing dust control and slag removal technologies for broken and soft coal seams are insufficient in dealing with the blowout phenomenon in pneumatic directional drilling of broken and soft coal seams. They fail to effectively control the instantaneous increase in gas concentration at the orifice during gas ejection, as well as the accompanying large-scale dust pollution. This not only endangers the safety of operators, but may also damage drilling equipment and the working environment, affecting the efficient management of gas.

[0007] Therefore, existing dust control and slag removal technologies for soft coal seams have problems such as ineffective reduction of dust and gas concentration at the borehole opening, low efficiency in solid drill cuttings removal, and the potential for gas blowouts, which urgently need to be addressed. Summary of the Invention

[0008] This invention provides a dust control and slag removal system and method for soft coal seams, which at least solves the problems of existing dust control and slag removal technologies for soft coal seams, such as the inability to effectively reduce the dust and gas concentration at the borehole opening, low efficiency in the removal of solid drill cuttings, and the possibility of gas blowouts.

[0009] To address the aforementioned problems, according to one aspect of the present invention, a dust control and slag removal system for soft coal seams is provided, comprising: an annular sealing assembly, a dust removal assembly, a first conveying pipe, a connecting assembly, a negative pressure suction assembly, a second conveying pipe, a gas-solid separator, a foam generator, and a screw conveyor; at least a portion of the annular sealing assembly is disposed within a borehole in the coal seam and is sealed to the inner wall of the borehole; the interior of the annular sealing assembly is connected to the interior of the borehole and the dust removal assembly; the lower part of the dust removal assembly is connected to one end of the first conveying pipe, and the other end of the first conveying pipe is connected to the outside; the connecting assembly is connected to one end of the dust removal assembly, the negative pressure suction assembly, and the second conveying pipe; the other end of the second conveying pipe is connected to the gas-solid separator; the foam generator is connected to the gas-solid separator. The gas-solid separator is connected to the screw conveyor at the bottom and the gas-solid separator at the top. The gas-solid mixture flowing out of the borehole enters the dust removal component through the annular sealing component. The dust removal component removes dust from the gas-solid mixture by spraying. The liquid mixture falling into the lower part of the dust removal component is removed through the first conveying pipe. The gas-solid mixture passing through the dust removal component enters the connecting component. The negative pressure suction component extracts the gas in the gas-solid mixture. The gas-solid mixture enters the gas-solid separator for gas and solid separation. The negative pressure suction component extracts the separated gas. The separated solid is transported to a designated location by the screw conveyor. The foam generator generates foam fluid and transports it to the gas-solid separator to assist in the separation of the gas-solid mixture.

[0010] Furthermore, the connecting component includes: a four-way structure, a first pagoda connector, and a second pagoda connector; the open end of the four-way structure is operably connected to the outside of the four-way structure; the four-way structure is connected to the dust removal component, the first pagoda connector, and the second pagoda connector respectively; the first pagoda connector is connected to the negative pressure suction component; the second pagoda connector is connected to the second conveying pipe; wherein, the first pagoda connector is closer to the dust removal component than the second pagoda connector, so that the gas-solid mixture after dust removal by the dust removal component flows sequentially through the first pagoda connector and the second pagoda connector; when the open end is connected to the outside of the four-way structure, the gas-solid mixture flows out of the four-way structure after flowing through the second pagoda connector.

[0011] Furthermore, the first pagoda connector has a first trapezoidal cavity communicating with the four-way structure, and the second pagoda connector has a second trapezoidal cavity communicating with the four-way structure; the first pagoda connector and / or the second pagoda connector are fixed to the four-way structure by welding; the first trapezoidal cavity reduces the extraction pressure difference by increasing the flow area at the inlet of the negative pressure suction component, thereby reducing the number of solid particles entering the negative pressure suction component; the second trapezoidal cavity is used to increase the flow area entering the second delivery pipe.

[0012] Furthermore, the connecting component also includes a sealing gasket; the open end of the four-way structure has a first flange, which is fixedly connected to the external pipeline by bolts; the connection end between the four-way structure and the dust removal component has a second flange, and the sealing gasket is placed between the second flange and the dust removal component to seal the connection end between the four-way structure and the dust removal component; the second flange is fixedly connected to the dust removal component by bolts.

[0013] Furthermore, the screw conveyor includes: a feed box, a hose, a screw conveyor component, a discharge box, and a hydraulic motor; the feed box is located at the bottom of the gas-solid separator and communicates with the interior of the gas-solid separator to receive the solids separated by the gas-solid separator; both ends of the hose are respectively connected to the feed box and the discharge box for conveying the solids separated by the gas-solid separator; the screw conveyor component is rotatably disposed inside the hose and is driven by the hydraulic motor; the hydraulic motor is used to drive the screw conveyor component to rotate, thereby driving the screw conveyor component to screw-propel the solids separated by the gas-solid separator into the discharge box; the discharge box can be switched on and off to communicate with the outside of the discharge box to discharge the solids separated by the gas-solid separator.

[0014] Furthermore, the dust control and slag removal system for soft coal seams also includes a buffer pipe and an expansion airbag; the two ends of the buffer pipe are respectively connected to the expansion airbag and the upper part of the gas-solid separator to transfer at least a portion of the gas separated in the gas-solid separator to the expansion airbag; the expansion airbag is connected to the negative pressure suction assembly to allow the gas in the expansion airbag to enter the negative pressure suction assembly; wherein, when a large amount of methane gas flows out of the gas-solid separator, the expansion airbag expands and contracts to buffer the impact of the gas on the gas-solid separator and the negative pressure suction assembly.

[0015] Furthermore, the foam generator includes: a main body, a nozzle, a connector, a screen plate, a foam outlet joint, a pressure gauge, a one-way valve, and a porous filling medium; the main body has a foam chamber inside, the nozzle is installed inside the foam chamber, and the nozzle is connected to one end of the one-way valve through a pipeline, while the other end of the one-way valve is connected to an external foam liquid pipeline; the connector is installed on the main body and is connected to the foam chamber and an external air pipeline respectively, with the connector facing the nozzle; the screen plate is installed inside the foam chamber; the porous filling medium fills the space between the foam chamber and the screen plate; the foam outlet joint is connected to the foam chamber and a gas-solid separator respectively; the pressure gauge is installed at the foam outlet joint to detect the pressure inside the foam chamber; wherein, the air ejected from the connector mixes with the foam liquid ejected from the nozzle to form a foam fluid, the screen plate is used to filter and disperse the foam fluid, the porous filling medium is used to increase the fluid contact area to refine the foam fluid; the one-way valve is used to prevent the foam fluid from flowing back into the external foam liquid pipeline.

[0016] Furthermore, the gas-solid separator includes: a main cylinder, an inlet flange, a foam connector, a gas outlet flange, a cleaning port flange, a slag discharge port flange, baffles, stiffeners, support legs, and supporting reinforcing ribs; the main cylinder has a separation chamber inside; the inlet flange is located on the main cylinder and is connected to the separation chamber and the second conveying pipe, allowing the gas-solid mixture to enter the separation chamber; the foam connector is located on the main cylinder and is connected to the separation chamber and the foam generator, allowing the foam fluid to enter the separation chamber; the gas outlet flange is located on the upper part of the main cylinder and is connected to the separation chamber and the negative pressure suction assembly, allowing the separated gas to enter the negative pressure suction assembly. Within the assembly: A cleaning port flange is located on the main cylinder and connects to both the separation chamber and the external cleaning water pipe, allowing external cleaning water to enter the separation chamber for cleaning; a slag discharge port flange is located at the bottom of the main cylinder and connects to both the separation chamber and the screw conveyor, allowing solids separated in the separation chamber to enter the screw conveyor; a baffle is located within the separation chamber to change the flow direction of the gas-solid mixture, promoting gas-solid separation; stiffening ribs are connected to the baffles to support them; support legs are fixedly located at the bottom of the main cylinder to support it; and supporting reinforcing ribs are connected to both the main cylinder and the support legs to strengthen them.

[0017] Further, the annular sealing assembly includes a connecting body, a packing member, and a clamping sleeve; the interior of the connecting body communicates with the interior of the borehole and the dust removal assembly; the packing member is disposed inside the connecting body and is limited in fit with the inner wall of the connecting body; the connecting body and the clamping sleeve are connected by a flange and bolts; the clamping sleeve is used to press and fix the packing member inside the connecting body; the end of the connecting body away from the clamping sleeve is fixedly connected to the dust removal assembly; the end of the clamping sleeve away from the connecting body is used to cooperate with external drilling equipment; and / or, the dust removal assembly includes a dust removal cylinder, at least one dust removal nozzle, and a lower connector; the dust removal cylinder has a dust removal chamber inside, and the dust removal nozzle is disposed in the dust removal chamber for spraying dust removal liquid droplets; the dust removal chamber communicates with the interior of the annular sealing assembly and the connecting assembly; the lower connector is fixed to the bottom of the dust removal cylinder by welding and communicates with the dust removal chamber and the first conveying pipe to discharge the liquid mixture falling into the lower part of the dust removal chamber.

[0018] According to another aspect of the present invention, a method for dust prevention and slag removal in soft coal seams is provided. This method is applied to the aforementioned soft coal seam dust prevention and slag removal system. The method further includes the following steps: sealing the borehole; the gas-solid mixture flowing out of the borehole enters a dust removal component through an annular sealing assembly; the dust removal component removes dust from the gas-solid mixture by spraying; the liquid mixture falling into the lower part of the dust removal component is removed through a first conveying pipe; the gas-solid mixture passing through the dust removal component enters a connecting component; a negative pressure suction component extracts the gas from the gas-solid mixture; the gas-solid mixture enters a gas-solid separator for gas and solid separation; the negative pressure suction component extracts the separated gas; the separated solid is conveyed to a designated location by a screw conveyor; a foam generator generates foam and conveys it to the gas-solid separator to assist in the separation of the gas-solid mixture.

[0019] The present invention provides a dust control and slag removal system for soft coal seams, comprising: an annular sealing assembly, a dust removal assembly, a first conveying pipe, a connecting assembly, a negative pressure suction assembly, a second conveying pipe, a gas-solid separator, a foam generator, and a screw conveyor; at least a portion of the annular sealing assembly is disposed within a borehole in the coal seam and is sealed to the inner wall of the borehole; the interior of the annular sealing assembly is connected to the interior of the borehole and the dust removal assembly; the lower part of the dust removal assembly is connected to one end of the first conveying pipe, and the other end of the first conveying pipe is connected to the outside; the connecting assembly is connected to one end of the dust removal assembly, the negative pressure suction assembly, and the second conveying pipe; the other end of the second conveying pipe is connected to the gas-solid separator; the foam generator is connected to the gas-solid separator; and the screw conveyor... The vortex conveyor is connected to the lower part of the gas-solid separator; the negative pressure suction assembly is connected to the upper part of the gas-solid separator; the gas-solid mixture flowing out from the borehole enters the dust removal assembly through the annular sealing assembly, and the dust removal assembly removes dust from the gas-solid mixture by spraying. The liquid mixture falling into the lower part of the dust removal assembly is removed through the first conveying pipe; the gas-solid mixture passing through the dust removal assembly enters the connecting assembly, and the negative pressure suction assembly extracts the gas in the gas-solid mixture. The gas-solid mixture enters the gas-solid separator for gas and solid separation. The negative pressure suction assembly extracts the separated gas, and the separated solid is transported to a designated location by the screw conveyor; the foam generator generates foam fluid and transports it into the gas-solid separator to assist in the separation of the gas-solid mixture.

[0020] This invention employs an annular sealing assembly that fits tightly against the inner wall of the borehole, forming a good seal and guiding the gas-solid mixture into the dust removal assembly. By coordinating the dust removal assembly, foam generator, and gas-solid separator, a multi-stage dust removal system is formed. The dust removal assembly uses spray to pre-treat the mixture, wetting the dust particles and causing them to settle. The settled mixture is then removed through a first conveying pipe, preventing secondary dust pollution. The gas-solid separator further separates the gas and solids, while the foam fluid generated by the foam generator is transported to the gas-solid separator. Through the encapsulation and coagulation effects of foam, the remaining tiny solid particles are separated, enabling the system to not only handle large amounts of dust in high-pressure gas and reduce the dust concentration at the orifice, but also effectively reduce the impact of dust on subsequent gas extraction pipelines and optimize gas control conditions. By setting up a connecting component, a screw conveyor, and a negative pressure suction component working in conjunction, the connecting component guides the pre-dust-removed gas-solid mixture to the negative pressure suction component and gas-solid separator. The negative pressure suction component extracts the gas components from the gas, and the screw conveyor is connected to the lower part of the gas-solid separator for efficient transport. The separated solid drill cuttings are transported to designated locations, avoiding environmental problems caused by drill cuttings accumulation. This system enables gravity discharge of large drill cuttings and remote transport of drill cuttings after gas-solid separation, improving transport efficiency and preventing drill cuttings accumulation and dust. The dust control and slag removal system for soft coal seams provided by this invention, through the coordinated operation of annular sealing components, dust removal components, a gas-solid separator, a foam generator, and a screw conveyor, effectively treats dust-laden gas and drill cuttings generated during high-pressure, high-flow-rate gas drilling in soft coal seams. Multi-stage coordinated dust removal reduces the dust concentration at the wellhead, and the efficient drill cuttings transport structure prevents drill cuttings accumulation and dust, optimizing gas control conditions and improving the safety and efficiency of downhole operations. The system's sealing and stability assurance scheme ensures reliable operation, while the convenient maintainability design reduces maintenance costs and extends the system's service life. This invention has a simple structure and low cost, facilitating assembly and subsequent maintenance. It solves the problems of existing soft coal seam dust control and slag removal technologies, such as the inability to effectively reduce wellhead dust and gas concentrations, low solid drill cuttings transport efficiency, and the potential for gas blowouts. It is suitable for large-scale promotion and use. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0022] Figure 1 A partial structural schematic diagram of the dust prevention and slag removal system for soft coal seams provided in an embodiment of the present invention is shown.

[0023] Figure 2A schematic diagram of the interconnected components of the dust prevention and slag removal system for soft coal seams provided in an embodiment of the present invention is shown.

[0024] Figure 3 A schematic diagram of the screw conveyor structure of the dust prevention and slag removal system for soft coal seams provided in an embodiment of the present invention is shown.

[0025] Figure 4 A cross-sectional view along the axial direction is shown of the foam generator of the dust prevention and slag removal system for soft coal seams provided in an embodiment of the present invention;

[0026] Figure 5 This diagram shows a partial schematic of the main cylinder of the gas-solid separator in the dust and slag removal system for soft coal seams provided in an embodiment of the present invention.

[0027] Figure 6 This diagram shows a partial axial section of the annular hole sealing assembly of the dust prevention and slag removal system for soft coal seams provided in an embodiment of the present invention.

[0028] Figure 7 The diagram shows a partial structural schematic of the dust removal cylinder in a cross-sectional view of the dust removal component of the dust removal system for dust prevention and slag removal in soft coal seams provided in an embodiment of the present invention.

[0029] The above figures include the following reference numerals:

[0030] 10. Ring hole sealing assembly; 11. Connecting body; 12. Packing packing; 13. Compression sleeve;

[0031] 20. Dust removal assembly; 21. Dust removal cylinder; 211. Dust removal chamber; 22. Dust removal nozzle; 23. Lower connector;

[0032] 30. First conveying pipe;

[0033] 40. Connecting component; 41. Four-way structure; 411. First flange; 412. Second flange; 42. First pagoda joint; 421. First trapezoidal cavity; 43. Second pagoda joint; 431. Second trapezoidal cavity; 44. Sealing gasket;

[0034] 50. Second delivery pipe;

[0035] 60. Gas-solid separator; 61. Main cylinder; 611. Separation chamber; 62. Inlet flange; 63. Foam connector; 64. Gas outlet flange; 65. Cleaning port flange; 66. Slag discharge port flange; 67. Baffle; 68. Rib plate; 69. Support leg; 610. Support reinforcing rib;

[0036] 70. Foam generator; 71. Main body; 711. Foam chamber; 72. Nozzle; 73. Connector; 74. Screen plate; 75. Foam outlet connector; 76. Pressure gauge; 77. Check valve; 78. Porous filling medium;

[0037] 80. Screw conveyor; 81. Feed box; 82. Hose; 83. Screw conveyor component; 84. Discharge box; 85. Hydraulic motor;

[0038] 90. Buffer tube;

[0039] 100. Inflatable airbag. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] like Figures 1 to 7As shown, an embodiment of the present invention provides a dust control and slag removal system for soft coal seams, comprising: an annular sealing assembly 10, a dust removal assembly 20, a first conveying pipe 30, a connecting assembly 40, a negative pressure suction assembly, a second conveying pipe 50, a gas-solid separator 60, a foam generator 70, and a screw conveyor 80; at least a portion of the annular sealing assembly 10 is disposed within a borehole in the coal seam and is sealed to the inner wall of the borehole; the interior of the annular sealing assembly 10 is connected to the interior of the borehole and the dust removal assembly 20; the lower part of the dust removal assembly 20 is connected to one end of the first conveying pipe 30, and the other end of the first conveying pipe 30 is connected to the outside; the connecting assembly 40 is connected to one end of the dust removal assembly 20, the negative pressure suction assembly, and the second conveying pipe 50; the other end of the second conveying pipe 50 is connected to the gas-solid separator 60; the foam generator 70 is connected to the gas-solid separator... The gas-solid separator 60 is connected to the screw conveyor 80; the lower part of the gas-solid separator 60 is connected to the screw conveyor 80; the upper part of the negative pressure suction assembly is connected to the negative pressure suction assembly 60; wherein, the gas-solid mixture flowing out from the borehole enters the dust removal assembly 20 through the annular hole sealing assembly 10, the dust removal assembly 20 removes dust from the gas-solid mixture by spraying, and the liquid mixture falling into the lower part of the dust removal assembly 20 is removed through the first conveying pipe 30; the gas-solid mixture passing through the dust removal assembly 20 enters the connecting assembly 40, the negative pressure suction assembly extracts the gas in the gas-solid mixture, the gas-solid mixture enters the gas-solid separator 60 for gas and solid separation, the negative pressure suction assembly extracts the separated gas, and the separated solid is transported to a designated location by the screw conveyor 80; the foam generator 70 generates foam fluid and transports it into the gas-solid separator 60 to assist in the separation of the gas-solid mixture.

[0042] This invention utilizes an annular sealing assembly 10, which fits tightly against the inner wall of the borehole to form a good seal, guiding the gas-solid mixture into the dust removal assembly 20. By coordinating the dust removal assembly 20, the foam generator 70, and the gas-solid separator 60, a multi-stage dust removal system is formed. The dust removal assembly 20 uses spray to pre-treat the gas-solid mixture, wetting the dust particles and causing them to settle. The settled mixture is then removed through the first conveying pipe 30, preventing secondary dust pollution. The gas-solid separator 60 further separates the gas and solids, while the foam generator 70 produces foam... The foamed fluid is conveyed to the gas-solid separator 60. Through the encapsulation and agglomeration effect of the foam, it assists in separating the remaining fine solid particles. This allows the system to not only handle large amounts of dust in high-pressure gas and reduce the dust concentration at the orifice, but also effectively reduce the impact of dust on subsequent gas extraction pipelines, optimizing gas control conditions. The system is constructed by coordinating a connecting component 40, a screw conveyor 80, and a negative pressure suction component. The connecting component 40 guides the pre-dust-removed gas-solid mixture to the negative pressure suction component and the gas-solid separator 60. The negative pressure suction component extracts the gas components from the gas, and the screw conveyor 80 works in conjunction with the gas-solid separator... The lower part of the separator 60 is connected to efficiently transport the separated solid drill cuttings to a designated location, avoiding environmental problems caused by drill cuttings accumulation. It achieves gravity discharge of large drill cuttings and remote transport of drill cuttings after gas-solid separation, improving transport efficiency and preventing drill cuttings accumulation and dust generation. The dust prevention and slag removal system for soft coal seams provided by this invention, through the coordinated operation of the annular sealing assembly 10, dust removal assembly 20, gas-solid separator 60, foam generator 70, and screw conveyor 80, effectively treats dust-laden gas and drill cuttings generated during high-pressure, high-flow-rate gas drilling in soft coal seams. Multi-stage coordinated dust removal reduces... This invention reduces the dust concentration at the wellhead, and the efficient drill cuttings conveying structure avoids drill cuttings accumulation and dust generation, optimizes gas control conditions, and improves the safety and efficiency of downhole operations. The system's sealing and stability assurance scheme ensures reliable system operation, while the convenient maintainability design reduces maintenance costs and extends the system's service life. This invention has a simple structure and low cost, is easy to assemble and maintain, and solves the problems of existing dust prevention and slag removal technologies for soft coal seams, such as the inability to effectively reduce the dust and gas concentration at the wellhead, low efficiency in solid drill cuttings transportation, and the possibility of gas blowouts. It is suitable for large-scale promotion and use.

[0043] like Figure 2As shown, the connecting component 40 includes: a four-way structure 41, a first pagoda connector 42, and a second pagoda connector 43; the open end of the four-way structure 41 is operably connected to the outside of the four-way structure 41; the four-way structure 41 is connected to the dust removal component 20, the first pagoda connector 42, and the second pagoda connector 43 respectively; the first pagoda connector 42 is connected to the negative pressure suction component; the second pagoda connector 43 is connected to the second conveying pipe 50; wherein, the first pagoda connector 42 is closer to the dust removal component 20 than the second pagoda connector 43, so that the gas-solid mixture after dust removal by the dust removal component 20 flows sequentially through the first pagoda connector 42 and the second pagoda connector 43; when the open end is connected to the outside of the four-way structure 41, the gas-solid mixture flows out of the four-way structure 41 after flowing through the second pagoda connector 43.

[0044] This invention, by incorporating a connecting component 40, ensures that the gas-solid mixture, after initial purification by the dust removal component, flows sequentially through the first pagoda connector 42 and the second pagoda connector 43. Finally, when the open end connects to the outside of the four-way structure 41, the gas-solid mixture is discharged outward through the second pagoda connector 43. This design achieves staged processing of the gas-solid mixture, improving the efficiency of subsequent suction and transportation, while also reducing environmental impact and ensuring the smooth progress of drilling operations and the safety of downhole personnel.

[0045] like Figure 2 As shown, the first pagoda connector 42 has a first trapezoidal cavity 421 communicating with the four-way structure 41, and the second pagoda connector 43 has a second trapezoidal cavity 431 communicating with the four-way structure 41; the first pagoda connector 42 and / or the second pagoda connector 43 are fixed to the four-way structure 41 by welding; the first trapezoidal cavity 421 reduces the extraction pressure difference by increasing the flow area at the inlet of the negative pressure suction component, thereby reducing the number of solid particles entering the negative pressure suction component; the second trapezoidal cavity 431 is used to increase the flow area entering the second delivery pipe 50.

[0046] This invention, by setting a first trapezoidal cavity 421, increases the gas flow area at the inlet of the negative pressure suction component, thereby reducing the extraction pressure difference and thus reducing the number of solid particles entering the negative pressure suction component. This optimizes the gas purification process at the wellhead and reduces the risk of gas extraction pipelines being blocked by drill cuttings. The second trapezoidal cavity 431 increases the flow area of ​​gas entering the second delivery pipe 50, promoting the smooth discharge of large drill cuttings, preventing drill cuttings accumulation around the wellhead, and reducing the impact on the working environment. These two specifically designed trapezoidal cavities not only improve the system's sealing performance and dust and slag removal efficiency but also enhance the system's adaptability and stability under high-pressure, high-flow-rate gas drilling conditions in soft coal seams, creating a safer and cleaner environment for downhole operations.

[0047] like Figure 2As shown, the connecting component 40 also includes a sealing gasket 44; the open end of the four-way structure 41 has a first flange 411, which is fixedly connected to the external pipeline by bolts; the connection end between the four-way structure 41 and the dust removal component 20 has a second flange 412, and the sealing gasket 44 is disposed between the second flange 412 and the dust removal component 20 to seal the connection end between the four-way structure 41 and the dust removal component 20; the second flange 412 is fixedly connected to the dust removal component 20 by bolts.

[0048] This invention enhances the sealing between the connecting component 40 and the dust removal component 20 by setting a sealing gasket 44. The open end of the four-way structure 41 is equipped with a first flange 411 for secure connection to external pipelines, ensuring stable gas flow during drilling. At the junction of the four-way structure 41 and the dust removal component 20, a second flange 412 works in conjunction with the sealing gasket 44, and is bolted together to effectively seal the connection gap, preventing leakage of dust or gas carried during drilling. This ensures the airtightness and reliability of the entire system, thereby improving the safety and dust control effect of drilling operations. Through this double-sealing flange connection design, the system can not only withstand the challenges of high-pressure, high-flow-rate gas drilling but also operate stably under different working conditions, ensuring effective control and treatment of wellhead dust and drill cuttings. When the first flange 411 is connected to the external pipeline and the second flange 412 is connected to the dust removal component 20, the bolt tightening provides additional connection strength, making the connection between components tighter and less prone to loosening, further improving the overall stability and operational efficiency of the system.

[0049] like Figure 3 As shown, the screw conveyor 80 includes: a feed box 81, a hose 82, a screw conveyor 83, a discharge box 84, and a hydraulic motor 85; the feed box 81 is located at the lower part of the gas-solid separator 60 and communicates with the interior of the gas-solid separator 60 to receive the solids separated by the gas-solid separator 60; the two ends of the hose 82 are respectively connected to the feed box 81 and the discharge box 84 for conveying the solids separated by the gas-solid separator 60; the screw conveyor 83 is rotatably disposed inside the hose 82 and is driven by the hydraulic motor 85; the hydraulic motor 85 is used to drive the screw conveyor 83 to rotate, so as to drive the screw conveyor 83 to screw-propel the solids separated by the gas-solid separator 60 into the discharge box 84; the discharge box 84 is configurably connected to the outside of the discharge box 84 to discharge the solids separated by the gas-solid separator 60.

[0050] This invention establishes a complete continuous drilling cuttings conveying system by configuring a screw conveyor 80, which consists of a feed box 81, a hose 82, a screw conveyor component 83, a discharge box 84, and a hydraulic motor 85. The feed box 81 is connected to the lower part of the gas-solid separator 60 and directly communicates with its interior, receiving the solid drilling cuttings separated by the separator. The hose 82 connects to the feed box 81 and the discharge box 84 at both ends, providing a flexible conveying channel for the drilling cuttings and adapting to the space constraints of downhole operations. The screw conveyor component 83 is located inside the hose 82 and is driven by the hydraulic motor 85, which provides power to rotate and propel the screw conveyor 83, efficiently pushing the solid drilling cuttings separated by the gas-solid separator 60 to the discharge box 84. The discharge box 84 has a switchable outlet for timely discharge of solid drilling cuttings, achieving continuous, stable, and long-range drilling cuttings conveying. This design, through the principle of spiral propulsion combined with the stable output of hydraulic motor 85, effectively solves the problem of timely removal of drill cuttings during high-pressure, high-flow-rate gas drilling in underground mines, ensuring cleanliness and safety at the work site, while also improving the efficiency of gas control and the safety of coal mining.

[0051] In one specific embodiment of the present invention, the screw conveyor 80 can be replaced by a chain conveyor, which uses a chain to drive the chain plates to transport drill cuttings from the feed end to the discharge end; alternatively, a pneumatic conveying system can be used to transport drill cuttings in a pipeline using the kinetic energy of air. The common feature of the above structures is that the chain conveyor, the pneumatic conveying system, and the original screw conveyor 80 all aim to transport drill cuttings from the borehole to a designated location, solving the problem of drill cuttings discharge and preventing drill cuttings accumulation from affecting the working environment and efficiency.

[0052] like Figure 1 As shown, the dust and slag removal system for soft coal seams also includes a buffer pipe 90 and an expansion airbag 100. The two ends of the buffer pipe 90 are respectively connected to the expansion airbag 100 and the upper part of the gas-solid separator 60 to transfer at least a portion of the gas separated in the gas-solid separator 60 to the expansion airbag 100. The expansion airbag 100 is connected to the negative pressure suction assembly to allow the gas in the expansion airbag 100 to enter the negative pressure suction assembly. When a large amount of methane gas flows out of the gas-solid separator 60, the expansion airbag 100 expands to contain it, thereby buffering the impact of the gas on the gas-solid separator 60 and the negative pressure suction assembly.

[0053] This invention utilizes a buffer pipe 90 and an expansion bladder 100. One end of the buffer pipe 90 is connected to the expansion bladder 100, and the other end communicates with the upper part of the gas-solid separator 60, thereby guiding a portion of the gas separated inside the gas-solid separator 60 to the expansion bladder 100. The expansion bladder 100 is further connected to a negative pressure suction assembly, allowing the gas collected inside the expansion bladder 100 to be extracted by the negative pressure suction assembly. When the gas-solid separator 60 encounters a sudden outflow of a large amount of methane gas, the expansion bladder 100 can rapidly expand, acting as a temporary storage container to effectively absorb and mitigate the impact of the gas on the gas-solid separator 60 and the negative pressure suction assembly, ensuring the stability and safety of the system operation. Through this buffering mechanism, the system can not only handle continuous dust-laden gas flows but also effectively cope with sudden high-pressure gas emissions, ensuring the high efficiency and stability of the entire soft coal seam dust prevention and slag removal system.

[0054] like Figure 4 As shown, the foam generator 70 includes: a main body 71, a nozzle 72, a connector 73, a screen plate 74, a foam outlet connector 75, a pressure gauge 76, a one-way valve 77, and a porous filling medium 78; the main body 71 has a foam cavity 711 inside, the nozzle 72 is disposed in the foam cavity 711, and the nozzle 72 is connected to one end of the one-way valve 77 through a pipeline, the other end of the one-way valve 77 is connected to an external foam liquid pipeline; the connector 73 is disposed on the main body 71 and is connected to the foam cavity 711 and an external air pipeline respectively, and the connector 73 is oriented towards the nozzle 72; the screen plate 74 is disposed in the foam cavity. Inside 711; porous filling medium 78 fills the space between foam cavity 711 and screen plate 74; foam outlet connector 75 is connected to foam cavity 711 and gas-solid separator 60 respectively; pressure gauge 76 is installed at foam outlet connector 75 to detect the pressure inside foam cavity 711; wherein, air ejected from connector 73 mixes with foam liquid ejected from nozzle 72 to form foam fluid, screen plate 74 is used to filter and disperse foam fluid, porous filling medium 78 is used to increase fluid contact area to refine foam fluid; one-way valve 77 is used to prevent foam fluid from flowing back into external foam liquid pipeline.

[0055] This invention comprises a foam generator 70 including a main body 71, a nozzle 72, a connector 73, a screen plate 74, a foam outlet connector 75, a pressure gauge 76, a one-way valve 77, and a porous filling medium 78. Inside the foam chamber 711 of the main body 71, the nozzle 72 is connected to one end of the one-way valve 77 via a pipeline, the other end of which is connected to an external foam liquid pipeline. The connector 73 is connected to both the foam chamber 711 and an external air pipeline, and is positioned towards the nozzle 72. The screen plate 74 is located within the foam chamber 711, and the porous filling medium 78 fills the space between the screen plate 74 and the foam chamber 711. The foam outlet connector 75 connects the foam chamber 711 to a gas-solid separator 60. The pressure gauge 76 is located at the foam outlet connector 75 to monitor the pressure within the foam chamber 711. During operation, external air is ejected from connector 73 and mixed with foam liquid, forming foam fluid through nozzle 72. Screen plate 74 filters and disperses the foam fluid, while porous filling medium 78 increases the fluid contact area and refines the foam fluid. One-way valve 77 prevents the foam fluid from flowing back into the external foam liquid pipeline. This design improves the separation effect of gas-solid separator 60 by precisely controlling the mixing of foam liquid and external air, helping to reduce the dust concentration at the wellhead and improve the quality of the drilling site working environment.

[0056] like Figure 5 As shown, the gas-solid separator 60 includes: a main cylinder 61, an inlet flange 62, a foam connector 63, a gas outlet flange 64, a cleaning port flange 65, a slag discharge port flange 66, a baffle 67, a stiffener 68, a support leg 69, and a support reinforcing rib 610; the main cylinder 61 has a separation chamber 611 inside; the inlet flange 62 is disposed on the main cylinder 61 and is connected to the separation chamber 611 and the second conveying pipe 50 respectively, so that the gas-solid mixture enters the separation chamber 611; the foam connector 63 is disposed on the main cylinder 61 and is connected to the separation chamber 611 and the foam generator 70 respectively, so that the foam fluid enters the separation chamber 611; the gas outlet flange 64 is disposed on the upper part of the main cylinder 61 and is connected to the separation chamber 611 and the negative pressure suction assembly respectively, so that the separated gas enters the negative pressure suction assembly. Inside the suction assembly; a cleaning port flange joint 65 is installed on the main cylinder 61 and is connected to the separation chamber 611 and the external cleaning water pipe, so that external cleaning water can enter the separation chamber 611 for cleaning; a slag discharge port flange joint 66 is installed at the lower part of the main cylinder 61 and is connected to the separation chamber 611 and the screw conveyor 80, so that the solids separated in the separation chamber 611 can enter the screw conveyor 80; a baffle 67 is installed in the separation chamber 611 and is used to change the flow direction of the gas-solid mixture in the separation chamber 611 to promote the separation of gas and solid; a stiffener 68 is connected to the baffle 67 and is used to support the baffle 67; a support leg 69 is fixedly installed at the lower part of the main cylinder 61 and is used to support the main cylinder 61; a support reinforcing rib 610 is connected to the main cylinder 61 and the support leg 69, respectively, and is used to reinforce the support leg 69.

[0057] This invention relates to a gas-solid separator 60 comprising a main cylinder 61, an inlet flange 62, a foam connector 63, a gas outlet flange 64, a cleaning port flange 65, a slag discharge port flange 66, a baffle 67, stiffening plates 68, support legs 69, and supporting reinforcing ribs 610. The main cylinder 61 contains a separation chamber 611. The inlet flange 62 is located on the main cylinder 61 and connects to the separation chamber 611 and the second conveying pipe 50, guiding the gas-solid mixture into the separation chamber for primary separation. The foam connector 63 is also located on the main cylinder 61 and connects to the separation chamber 611 and the foam generator 70, introducing foam fluid to enhance the gas-solid separation process. The gas outlet flange 64 is located on the upper part of the main cylinder 61 and connects to the separation chamber 611 and the negative pressure suction assembly. The cleaning port flange 65 is located on the main cylinder 61 and communicates with the separation chamber 611 and the external cleaning water pipe, facilitating regular cleaning of the separator's interior and maintaining the equipment's cleanliness and efficiency. The slag discharge flange joint 66 is located at the lower part of the main cylinder 61, connecting with the separation chamber 611 and the screw conveyor 80, ensuring that the separated solid particles smoothly enter the screw conveyor 80. The baffle 67 is placed inside the separation chamber 611, its function being to change the flow direction of the gas-solid mixture, promoting effective separation of solids and gases. The stiffening rib 68 cooperates with the baffle 67 to enhance the structural stability of the baffle 67. The support leg 69 is fixed to the lower part of the main cylinder 61, providing stable support for the device. The supporting reinforcing rib 610 is connected to both the main cylinder 61 and the support leg 69, enhancing the structural strength and stability of the entire device, ensuring that the gas-solid separator 60 can operate stably in complex environments and efficiently complete the gas-solid separation task. Through the layout and functional integration of the above components, the gas-solid separator 60 can quickly separate and process dust and drill cuttings during high-pressure, high-flow-rate gas drilling, effectively reducing the dust concentration at the wellhead and improving the efficiency and safety of gas control in downhole operations.

[0058] like Figure 6 and Figure 7As shown, the annular sealing assembly 10 includes a connecting body 11, a packing member 12, and a clamping sleeve 13. The interior of the connecting body 11 communicates with the interior of the borehole and the dust removal assembly 20. The packing member 12 is disposed inside the connecting body 11 and is limited and fitted against the inner wall of the connecting body 11. The connecting body 11 and the clamping sleeve 13 are connected by a flange and bolts. The clamping sleeve 13 is used to press and fix the packing member 12 inside the connecting body 11. The end of the connecting body 11 away from the clamping sleeve 13 is fixedly connected to the dust removal assembly 20. The end of the clamping sleeve 13 away from the connecting body 11 is used for... For use with external drilling equipment; and / or, the dust removal assembly 20 includes a dust removal cylinder 21, at least one dust removal nozzle 22, and a lower connector 23; the dust removal cylinder 21 has a dust removal chamber 211 inside, and the dust removal nozzle 22 is disposed in the dust removal chamber 211 for spraying dust removal liquid droplets; the dust removal chamber 211 is connected to the interior of the annular hole sealing assembly 10 and the connecting assembly 40 respectively; the lower connector 23 is fixed to the bottom of the dust removal cylinder 21 by welding, and is connected to the dust removal chamber 211 and the first conveying pipe 30 respectively, so as to discharge the liquid mixture falling into the lower part of the dust removal chamber 211.

[0059] This invention utilizes an annular sealing assembly 10, comprising a connecting body 11, a packing member 12, and a clamping sleeve 13. The connecting body 11 is internally connected to a drilling and dust removal assembly 20, while the packing member 12 is disposed inside the connecting body 11 and fitted against its inner wall to ensure a tight fit with the drilling equipment. The clamping sleeve 13, connected by a flange and bolts, firmly presses the packing member 12 into the connecting body 11, achieving an effective seal between the drill rod and the annular space at the orifice. One end of the connecting body 11 is fixedly connected to the dust removal assembly 20, while the other end is used to cooperate with external drilling equipment to guide dust-laden gas into the next processing stage. The dust removal assembly 20 includes a dust removal cylinder 21, at least one dust removal nozzle 22, and a lower connector 23. The dust removal cylinder 21 contains a dust removal chamber 211, within which the dust removal nozzle 22 is located, for spraying dust removal droplets that mix with the dust-laden gas, causing the dust to become wet, heavier, and settle. The lower connector 23 is welded and fixed to the bottom of the dust collector cylinder 21, and is connected to the dust collector chamber 211 and the first conveying pipe 30. It is responsible for discharging the liquid mixture falling into the lower part of the dust collector chamber 211, which includes humidified dust and water. Through the coordinated work of the various components of the dust collector assembly 20, the dust-laden gas discharged from the borehole is pre-humidified, thereby reducing the suspended dust in the dust-laden gas, thus mitigating the impact on subsequent gas extraction and components, and improving the operating efficiency and safety of the entire system.

[0060] In one specific embodiment of the present invention, the packing seal of the annular sealing assembly 10 can be replaced by a rotary sealing device, which achieves dynamic sealing through bearings and a rubber core. The flange bolt connection can be replaced by a clamp connection. Commonalities: Rotary seals and packing seals, clamp connections and flange bolt connections, despite their different structural forms and operating principles, all revolve around ensuring the system's sealing performance, connection stability, and structural stability, ensuring reliable operation of the system under complex downhole conditions.

[0061] In one specific embodiment of the present invention, an electrostatic precipitator can be used to replace part of the spray dust removal and foam adsorption functions for dust removal. The electrostatic precipitator uses a high-voltage electric field to charge dust particles, which are then adsorbed onto the electrodes under the influence of the electric field force, thereby achieving dust removal. Alternatively, a cyclone dust collector can also be used as an alternative to the gas-solid separator 60, which separates solid particles from the gas-solid mixture using centrifugal force. The commonality is that whether it's the original multi-stage dust removal system or alternative methods such as electrostatic precipitator and cyclone dust collector, the core objective is to separate dust particles from the gas, reduce the dust concentration, and thus purify the gas and improve the downhole working environment.

[0062] like Figures 1 to 7 As shown, the present invention also provides a method for dust prevention and slag removal in soft coal seams. Applying the aforementioned system for dust prevention and slag removal in soft coal seams, the method further includes the following steps: sealing the borehole; the gas-solid mixture flowing out of the borehole enters the dust removal component 20 through the annular sealing assembly 10; the dust removal component 20 removes dust from the gas-solid mixture through spraying; the liquid mixture falling to the lower part of the dust removal component 20 is removed through the first conveying pipe 30; the gas-solid mixture passing through the dust removal component 20 enters the connecting component 40; the negative pressure suction component extracts the gas in the gas-solid mixture; the gas-solid mixture enters the gas-solid separator 60 for gas and solid separation; the negative pressure suction component extracts the separated gas; the separated solid is conveyed to a designated location by the screw conveyor 80; the foam generator 70 generates foam and conveys it to the gas-solid separator 60 to assist in the separation of the gas-solid mixture. The present invention is designed to achieve this.

[0063] This invention effectively treats the gas-solid mixture discharged from the borehole by coordinating the functions of the annular sealing assembly 10, dust removal assembly 20, first conveying pipe 30, connecting assembly 40, negative pressure suction assembly, second conveying pipe 50, gas-solid separator 60, foam generator 70, and screw conveyor 80. In this method, the gas-solid mixture first enters the dust removal assembly 20 through the annular sealing assembly 10. After being sprayed for dust removal, the liquid mixture is removed by the first conveying pipe 30. Then, the gas-solid mixture further circulates within the connecting assembly 40. The gas is extracted by the negative pressure suction assembly, while the remaining gas-solid mixture enters the gas-solid separator 60 for fine separation. During this process, the foam fluid generated by the foam generator 70 is sent to the gas-solid separator 60, effectively assisting in the separation of solid particles and gas. The separated gas is further processed by the negative pressure suction assembly, while the solid drill cuttings are stably transported to a predetermined location by the screw conveyor 80. The implementation of this method not only strengthens the control of wellhead dust and improves the efficiency of drill cuttings discharge, but also significantly enhances the effectiveness of gas control, improves the downhole working environment, and ensures the safety and health of personnel.

[0064] The specific working process and principle of one embodiment of the present invention will now be described in detail as follows:

[0065] First, the connecting assembly 40 is installed at the borehole opening via flange bolts, using the sealing gasket 44 to block part of the gas-solid mixture. The packing 12 of the annular sealing assembly 10 is installed inside the connecting body 11, and then the compression sleeve 13 is connected to the flange bolts of the connecting body 11 to tighten the packing 12, achieving a seal between the drill pipe and the annular space at the borehole opening, preventing leakage of dust-containing gas. Simultaneously, all components are connected according to design requirements to ensure the normal operation of the negative pressure suction equipment, static pressure water cleaning device, etc.

[0066] During drilling, high-velocity gas carrying a large amount of coal dust particles is discharged from the borehole into the connecting component 40. The trapezoidal cavities arranged vertically in the connecting component 40 play a role. The lower second trapezoidal cavity 431 allows large drill cuttings to be discharged more smoothly by gravity, while the upper first trapezoidal cavity 421 reduces the negative pressure, reducing the amount of solid particles entering the gas extraction pipeline. A small portion of the gas containing small particles enters the dust removal component 20, the size of which, the number of nozzles, and their arrangement can be adjusted according to the gas flow rate. Several dust removal nozzles 22 spray mist water, which mixes with the dust-laden gas, wetting, increasing the weight of the dust particles, and causing them to settle, reducing the number of escaped solid particles.

[0067] Subsequently, the foam generator 70 begins operation. Compressed air enters through connector 73, and foam liquid enters the main body 71 through one-way valve 77. The mixture is thoroughly mixed at nozzle 72, and after passing through screen plate 74 and porous filling medium 78, the generated foam is output from foam outlet connector 75 to the orifice area, further adsorbing and encapsulating dust. The gas after preliminary dust removal and foam assistance, along with unsettled solid particles, enters the gas-solid separator 60. Internal baffles 67 in the main cylinder 61 change the flow direction of the gas-solid mixture, promoting particle settling. Gas-solid separation is achieved here. The separated gas can be drawn down by the negative pressure suction component to reduce the gas concentration. When a large amount of gas is ejected, the expansion bladder 100 can rapidly expand to reduce the impact intensity and ensure system safety.

[0068] Finally, the separated drill cuttings fall into the feed box 81 of the screw conveyor 80. The feed box 81 facilitates the introduction of drill cuttings, the hose 82 provides a conveying channel, and the screw conveyor 83 rotates under the drive of the hydraulic motor 85. The screw propels the drill cuttings from the feed box 81 to the discharge box 84, which is then remotely transported out of the drilling site to prevent drill cuttings from accumulating.

[0069] In addition, during or after system operation, a static pressure water cleaning device can be connected through the cleaning connector of the gas-solid separator 60 to clean the inside of the device, remove residual dust and drilling slag, ensure smooth operation of the system next time, and maintain stable dust prevention and slag removal functions.

[0070] In summary, this invention provides a dust control and slag removal system and method for soft coal seams. The invention utilizes an annular sealing assembly 10, which fits tightly against the inner wall of the borehole to form a good seal, guiding the gas-solid mixture into the dust removal assembly 20. By coordinating the dust removal assembly 20, foam generator 70, and gas-solid separator 60, a multi-stage dust removal system is formed. The dust removal assembly 20 can perform preliminary treatment of the gas-solid mixture through spraying, wetting the dust particles and causing them to settle. The settled mixture is then removed through the first conveying pipe 30, avoiding secondary dust pollution. The gas-solid separator 60 then... The system achieves gas-solid separation in one step. The foam fluid generated by the foam generator 70 is transported to the gas-solid separator 60. Through the encapsulation and coagulation effect of the foam, it assists in separating the remaining small solid particles. This allows the system to not only handle large amounts of dust in high-pressure gas and reduce the dust concentration at the orifice, but also effectively reduce the impact of dust on subsequent gas extraction pipelines and optimize gas control conditions. The system is further enhanced by the coordinated operation of the connecting component 40, the screw conveyor 80, and the negative pressure suction component. The connecting component 40 guides the pre-dust-removed gas-solid mixture to the negative pressure suction component and the gas-solid separator 60, while the negative pressure suction component extracts gas particles from the gas. The screw conveyor 80 is connected to the lower part of the gas-solid separator 60, efficiently transporting the separated solid drill cuttings to a designated location, avoiding environmental problems caused by drill cuttings accumulation. This achieves gravity discharge of large drill cuttings and remote transport of drill cuttings after gas-solid separation, improving transport efficiency and preventing drill cuttings accumulation and dust. The dust prevention and slag removal system for soft coal seams provided by this invention, through the coordinated operation of the annular sealing assembly 10, dust removal assembly 20, gas-solid separator 60, foam generator 70, and screw conveyor 80, effectively treats dust-laden gas and drill cuttings generated during high-pressure, high-flow-rate gas drilling in soft coal seams. Multi-stage synergistic dust removal reduces the dust concentration at the wellhead, while the efficient drill cuttings conveying structure avoids drill cuttings accumulation and dust generation, optimizes gas control conditions, and improves the safety and efficiency of downhole operations. The system sealing and stability assurance scheme ensures reliable system operation, while the convenient maintainability design reduces maintenance costs and extends the system's service life. This invention has a simple structure and low cost, is easy to assemble and maintain, and solves the problems of existing dust and slag removal technologies for soft coal seams, such as the inability to effectively reduce the dust and gas concentration at the wellhead, low efficiency in solid drill cuttings transportation, and the possibility of gas blowouts. It is suitable for large-scale promotion and use.

[0071] The technical features of the embodiments described above can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered to be within the scope of this specification.

[0072] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0073] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0074] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0075] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0076] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A dust control and slag removal system for soft coal seams, characterized in that, include: The annular sealing assembly (10), dust removal assembly (20), first conveying pipe (30), connecting assembly (40), negative pressure suction assembly, second conveying pipe (50), gas-solid separator (60), foam generator (70), and screw conveyor (80) are provided. At least a portion of the annular sealing assembly (10) is disposed in a borehole on the coal seam and is sealed to the inner wall of the borehole. The interior of the annular sealing assembly (10) is connected to the interior of the borehole and the dust removal assembly (20). The lower part of the dust removal assembly (20) is connected to one end of the first conveying pipe (30), and the other end of the first conveying pipe (30) is connected to the outside. The connecting assembly (40) is connected to one end of the dust removal assembly (20), the negative pressure suction assembly, and the second conveying pipe (50). The other end of the second conveying pipe (50) is connected to the gas-solid separator (60). The foam generator (70) is connected to the gas-solid separator (60). The screw conveyor (80) is connected to the gas-solid separator (60). 80) is connected to the lower part of the gas-solid separator (60); the negative pressure suction assembly is connected to the upper part of the gas-solid separator (60); wherein, the gas-solid mixture flowing out from the borehole enters the dust removal assembly (20) through the annular hole sealing assembly (10), the dust removal assembly (20) removes dust from the gas-solid mixture by spraying, and the liquid mixture falling into the lower part of the dust removal assembly (20) is removed through the first conveying pipe (30); the gas-solid mixture passing through the dust removal assembly (20) enters the connecting assembly (40), the negative pressure suction assembly extracts the gas in the gas-solid mixture, the gas-solid mixture enters the gas-solid separator (60) for gas and solid separation, the negative pressure suction assembly extracts the separated gas, and the separated solid is transported to a designated position through the screw conveyor (80); the foam generator (70) generates foam fluid and transports it to the gas-solid separator (60) to assist the separation of the gas-solid mixture.

2. The dust control and slag removal system for soft coal seams according to claim 1, characterized in that, The connecting component (40) includes: a four-way structure (41), a first pagoda connector (42), and a second pagoda connector (43); the open end of the four-way structure (41) is connected to the outside of the four-way structure (41) in a way that can be switched on and off; the four-way structure (41) is connected to the dust removal component (20), the first pagoda connector (42), and the second pagoda connector (43) respectively; the first pagoda connector (42) is connected to the negative pressure suction component; the second pagoda connector (43) is connected to the second delivery pipe (50); wherein, the first pagoda connector (42) is closer to the dust removal component (20) than the second pagoda connector (43), so that the gas-solid mixture after being dusted by the dust removal component (20) flows through the first pagoda connector (42) and the second pagoda connector (43) in sequence; when the open end is connected to the outside of the four-way structure (41), the gas-solid mixture flows out of the four-way structure (41) after flowing through the second pagoda connector (43).

3. The dust control and slag removal system for soft coal seams according to claim 2, characterized in that, The first pagoda connector (42) has a first trapezoidal cavity (421) communicating with the four-way structure (41), and the second pagoda connector (43) has a second trapezoidal cavity (431) communicating with the four-way structure (41); the first pagoda connector (42) and / or the second pagoda connector (43) are fixed to the four-way structure (41) by welding; the first trapezoidal cavity (421) reduces the extraction pressure difference by increasing the flow area at the inlet of the negative pressure suction component, thereby reducing the number of solid particles entering the negative pressure suction component; the second trapezoidal cavity (431) is used to increase the flow area entering the second delivery pipe (50).

4. The dust control and slag removal system for soft coal seams according to claim 2, characterized in that, The connecting component (40) further includes a sealing gasket (44); the open end of the four-way structure (41) has a first flange (411), which is fixedly connected to an external pipeline by bolts; the connection end between the four-way structure (41) and the dust removal component (20) has a second flange (412), and the sealing gasket (44) is disposed between the second flange (412) and the dust removal component (20) to seal the connection end between the four-way structure (41) and the dust removal component (20); the second flange (412) is fixedly connected to the dust removal component (20) by bolts.

5. The dust control and slag removal system for soft coal seams according to claim 1, characterized in that, The screw conveyor (80) includes: a feed box (81), a hose (82), a screw conveyor component (83), a discharge box (84), and a hydraulic motor (85); the feed box (81) is located at the lower part of the gas-solid separator (60) and communicates with the interior of the gas-solid separator (60) to receive the solids separated by the gas-solid separator (60); the two ends of the hose (82) are respectively connected to the feed box (81) and the discharge box (84) for conveying the solids separated by the gas-solid separator (60). The solids separated by the gas-solid separator (60) are rotatably disposed within the hose (82) and driven by the hydraulic motor (85). The hydraulic motor (85) drives the spiral conveyor (83) to rotate, thereby driving the spiral conveyor (83) to spirally propel the solids separated by the gas-solid separator (60) into the discharge box (84). The discharge box (84) is connected to the outside of the discharge box (84) to discharge the solids separated by the gas-solid separator (60).

6. The dust control and slag removal system for soft coal seams according to claim 1, characterized in that, The dust and slag removal system for the soft coal seam also includes a buffer pipe (90) and an expansion airbag (100); the two ends of the buffer pipe (90) are respectively connected to the expansion airbag (100) and the upper part of the gas-solid separator (60) to transfer at least a portion of the gas separated in the gas-solid separator (60) to the expansion airbag (100); the expansion airbag (100) is connected to the negative pressure suction assembly to allow the gas in the expansion airbag (100) to enter the negative pressure suction assembly; wherein, when a large amount of methane gas flows out in the gas-solid separator (60), the expansion airbag (100) expands to contain it, so as to buffer the impact of the gas on the gas-solid separator (60) and the negative pressure suction assembly.

7. The dust control and slag removal system for soft coal seams according to claim 1, characterized in that, The foam generator (70) includes: a main body (71), a nozzle (72), a connector (73), a screen plate (74), a foam outlet connector (75), a pressure gauge (76), a one-way valve (77), and a porous filling medium (78); the main body (71) has a foam cavity (711) inside, the nozzle (72) is disposed in the foam cavity (711), and the nozzle (72) is connected to one end of the one-way valve (77) through a pipeline, and the other end of the one-way valve (77) is connected to an external foam liquid pipeline; the connector (73) is disposed on the main body (71) and is connected to the foam cavity (711) and an external air pipeline respectively, and the connector (73) is disposed facing the nozzle (72); the screen plate (74) is disposed in the foam cavity. (711) Inside; the porous filling medium (78) fills between the foam cavity (711) and the screen plate (74); the foam outlet connector (75) is connected to the foam cavity (711) and the gas-solid separator (60) respectively; the pressure gauge (76) is set at the foam outlet connector (75) to detect the pressure inside the foam cavity (711); wherein, the air sprayed from the connector (73) mixes with the foam liquid sprayed from the nozzle (72) to form the foam fluid, the screen plate (74) is used to filter and disperse the foam fluid, the porous filling medium (78) is used to increase the fluid contact area to refine the foam fluid; the one-way valve (77) is used to prevent the foam fluid from flowing back into the external foam liquid pipeline.

8. The dust control and slag removal system for soft coal seams according to claim 1, characterized in that, The gas-solid separator (60) includes: a main cylinder (61), an inlet flange (62), a foam connector (63), a gas outlet flange (64), a cleaning port flange (65), a slag discharge port flange (66), a baffle (67), a stiffener (68), a support leg (69), and a support reinforcing rib (610); the main cylinder (61) has a separation chamber (611) inside; the inlet flange (62) is disposed on the main cylinder (61) and is connected to the separation chamber (611) and the second conveying... The pipe (50) is connected to allow the gas-solid mixture to enter the separation chamber (611); the foam connector (63) is disposed on the main cylinder (61) and is connected to the separation chamber (611) and the foam generator (70) respectively, so that the foam fluid enters the separation chamber (611); the gas outlet flange (64) is disposed on the upper part of the main cylinder (61) and is connected to the separation chamber (611) and the negative pressure suction assembly respectively, so that the separated gas enters the negative pressure suction assembly; The cleaning port flange joint (65) is installed on the main cylinder (61) and is connected to the separation chamber (611) and the external cleaning water pipe, respectively, so that external cleaning water enters the separation chamber (611) for cleaning; the slag discharge port flange joint (66) is installed at the lower part of the main cylinder (61) and is connected to the separation chamber (611) and the screw conveyor (80), respectively, so that the solids separated in the separation chamber (611) enter the screw conveyor (80); the baffle (67) is installed on the main cylinder (61). Inside the separation chamber (611), the baffle (67) is used to change the flow direction of the gas-solid mixture within the separation chamber (611) to promote the separation of gas and solid; the rib (68) is connected to the baffle (67) and is used to support the baffle (67); the support leg (69) is fixedly disposed at the lower part of the main cylinder (61) and is used to support the main cylinder (61); the supporting reinforcing rib (610) is connected to the main cylinder (61) and the support leg (69) respectively and is used to strengthen the support leg (69).

9. The dust control and slag removal system for soft coal seams according to claim 1, characterized in that, The annular sealing assembly (10) includes a connecting body (11), a packing member (12), and a clamping sleeve (13); the interior of the connecting body (11) is connected to the interior of the borehole and the dust removal assembly (20); the packing member (12) is disposed inside the connecting body (11) and is limited to the inner wall of the connecting body (11); the connecting body (11) and the clamping sleeve (13) are connected by a flange and bolts; the clamping sleeve (13) is used to press and fix the packing member (12) inside the connecting body (11); one end of the connecting body (11) away from the clamping sleeve (13) is fixedly connected to the dust removal assembly (20); one end of the clamping sleeve (13) away from the connecting body (11) is used to cooperate with external drilling equipment; And / or, the dust removal assembly (20) includes a dust removal cylinder (21), at least one dust removal nozzle (22) and a lower connector (23); the dust removal cylinder (21) has a dust removal chamber (211) inside, and the dust removal nozzle (22) is disposed in the dust removal chamber (211) for spraying dust removal droplets; the dust removal chamber (211) is connected to the interior of the annular hole sealing assembly (10) and the connecting assembly (40) respectively; the lower connector (23) is fixed to the bottom of the dust removal cylinder (21) by welding, and is connected to the dust removal chamber (211) and the first conveying pipe (30) respectively, so as to discharge the liquid mixture falling in the lower part of the dust removal chamber (211).

10. A method for dust prevention and slag removal in soft, fractured coal seams, characterized in that, The method for preventing dust and removing slag from crushed and soft coal seams is applied to the dust and slag removal system for crushed and soft coal seams according to any one of claims 1 to 9, and the method further includes the following steps: The borehole is sealed, and the gas-solid mixture flowing out of the borehole enters the dust removal assembly (20) through the annular sealing assembly (10). The dust removal assembly (20) removes dust from the gas-solid mixture by spraying. The liquid mixture falling into the lower part of the dust removal assembly (20) is removed through the first conveying pipe (30). The gas-solid mixture passing through the dust removal assembly (20) enters the connecting assembly (40). The negative pressure suction assembly extracts the gas in the gas-solid mixture. The gas-solid mixture enters the gas-solid separator (60) for gas and solid separation. The negative pressure suction assembly extracts the separated gas. The separated solid is transported to a designated location through the screw conveyor (80). The foam generator (70) generates foam and transports it to the gas-solid separator (60) to assist in the separation of the gas-solid mixture.

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