Method for preventing and controlling gob-side entry retaining goaf gas and fire composite disaster through rotating wind field

Abstract

The invention discloses a method for preventing and controlling gas and fire composite disasters in a gob-side entry retaining gob through a rotating wind field, and belongs to the technical field of coal-pillar-free mining of mines and disaster prevention and control of the gob-side entry retaining goa.The method comprises the steps that a local fan is arranged outside a track crossheading, and a rotating wind field generating device is arranged in the gob-side entry retaining on the air return side; the rotary wind field generating device is connected with the local fan through the air duct; high-pressure air flow is provided by a local fan, a rotating wind field which rotates and advances along the roadway is generated through a rotating wind field generating device, a high-pressure air ring is formed on the periphery of the roadway wall under the centrifugal force action of the rotating wind field, and the roadway side, the top plate and the bottom plate of the gob-side entry retaining are flexibly blocked through the high-pressure air ring. The plugging agent has multiple effects of increasing wind, increasing resistance and pressurizing for plugging, has a good plugging effect, is pollution-free, does not influence normal production of a working face, and can effectively prevent and control gas and fire composite disasters in a gob-side entry retaining goaf.

Description

Technical Field

[0001] This invention belongs to the field of coal pillarless mining and goaf disaster prevention and control technology, specifically a method for controlling the combined gas and fire disasters in goaf areas with rotating ventilation fields. Background Technology

[0002] Pillarless mining with roadway retention along the goaf can improve the resource recovery rate of a mine, extend its service life, reduce the amount of roadway excavation at the working face, alleviate the contradiction between mining and tunneling, and shorten the relocation time of the working face. It is an economical and effective coal mining method. This technology has been applied in many thin and medium-thick coal seam working faces with relatively good conditions in my country, achieving good results. However, when applied in mines with complex geological conditions, significant safety hazards still exist, the core issue being the risk of combined gas and fire disasters caused by the working face ventilation system.

[0003] Currently, the commonly used ventilation methods for the working face in the goaf-side pillarless mining technology are mainly Y-type ventilation and W-type ventilation. Among them, W-type ventilation has less disturbance to the goaf, but it is easy for gas to accumulate in the upper corner of the working face. If the gas concentration reaches the explosive limit, it is very easy to trigger a gas explosion accident once it encounters the high temperature or ignition source generated by the oxidation of residual coal in the goaf. Although Y-type ventilation can effectively discharge the gas in the upper corner of the working face through a reasonable airflow path and solve the problem of gas accumulation, the structural characteristics of the ventilation system lead to a significant increase in air leakage in the goaf. A large amount of fresh air flows into the goaf, which will accelerate the oxidation process of residual coal, providing sufficient oxygen for coal spontaneous combustion. Moreover, when a spontaneous combustion source appears in the goaf, the high temperature environment will aggravate the desorption of gas by the coal body, forming a compound disaster chain of "gas enrichment-coal spontaneous combustion" that promotes each other, greatly increasing the difficulty of accident prevention and control.

[0004] Therefore, the severe combined hazards of gas and spontaneous combustion in goaf areas have become a bottleneck restricting the promotion and application of pillarless mining technology along the goaf. Summary of the Invention

[0005] The purpose of this invention is to solve the problems existing in the prior art and to provide a method for controlling the combined disasters of gas and fire in goaf areas along the goaf by using a rotating wind field.

[0006] This invention is achieved through the following technical solution: A method for controlling combined gas and fire disasters in goaf-side roadways using a rotating ventilation system involves installing a local fan outside the track roadway and a rotating ventilation system at a certain distance from the goaf wall in the goaf-side roadway on the return air side. The rotating ventilation system is connected to the local fan via a ventilation duct. The local fan provides high-pressure airflow, which is then used by the rotating ventilation system to generate a rotating ventilation system that moves along the roadway. The centrifugal force of the rotating ventilation system creates a high-pressure air ring around the roadway wall, which is then used to flexibly seal the roadway walls, roof, and floor of the goaf-side roadway.

[0007] Furthermore, the rotating wind field generating device includes multiple main wind ducts connected in sequence. Multiple sets of circumferential air outlets are evenly distributed along the axial direction of the main wind duct. Each set of circumferential air outlets includes four air outlets arranged on the upper side, lower side, left side, and right side along the circumference of the main wind duct. The four air outlets are centrally symmetrically distributed. All four air outlets are connected to the interior of the main wind duct, forming an all-round airflow release channel. The compressed air provided by the local fan is guided through the interior of the main wind duct and flows out from each air outlet, forming a rotating wind field around the main wind duct.

[0008] Furthermore, the air outlet has a rectangular structure, and the included angle between each air outlet and the axis of the main air duct is set to 30°.

[0009] Furthermore, the length and width of the rectangular air outlet must match the overall specifications of the main air duct, including its diameter, axial length, and internal airflow rate. Specifically, the width of the air outlet is determined based on the diameter of the main air duct to ensure that the outlet fully utilizes the circumferential space of the duct. The length of the air outlet is determined based on the axial length of the main air duct and the number of air outlets on the same side to ensure that the total flow area of ​​all air outlets matches the airflow rate inside the main air duct. This avoids both airflow obstruction and excessive internal pressure due to an excessively small air outlet, and airflow dispersion and insufficient wind strength due to an excessively large air outlet, ultimately achieving the best balance between airflow output efficiency and wind field stability.

[0010] Furthermore, the two air outlets on the same side of two adjacent sets of circumferential air outlets on the main air duct have no axial overlap.

[0011] Furthermore, the two adjacent main air ducts are detachably connected by pipe clamps. The pipe clamps include two semi-circular ring clamps. The inner wall of the semi-circular ring clamps is provided with an anti-slip texture layer that matches the outer wall of the main air duct. The two ends of the two semi-circular ring clamps are fastened together by bolts and nuts.

[0012] Furthermore, the number of main wind tunnels can be flexibly configured according to the coverage requirements of the rotating wind field; when the axial length of the application scenario is large, the number of main wind tunnels can be increased to extend the axial coverage length of the wind field; when the axial length of the application scenario is small, the number of main wind tunnels can be reduced.

[0013] Furthermore, the airflow trajectory of the rotating wind field advances forward in a spiral manner and can cover the entire cross-section of the goaf-retention tunnel. The cross-section includes the space area enclosed by the tunnel walls, roof, and floor, ensuring no blind spots in airflow coverage. As the rotating wind field continues to advance within the goaf-retention tunnel, the airflow generates centrifugal force radially outward along the tunnel due to the rotational motion. The centrifugal force drives the airflow to diffuse towards the tunnel wall, roof wall, and floor wall. After being blocked by the walls, the airflow gathers around the tunnel wall, forming a continuous and unbroken high-pressure air ring that surrounds the entire circumference of the tunnel.

[0014] Furthermore, the air pressure of the high-pressure air ring is kept in balance with the air pressure of the external environment of the roadway, and the air pressure is evenly distributed along the circumference of the roadway, forming a dynamic balance between the roadway wall and the high-pressure air ring. The high-pressure air ring is closely attached to the sidewall, roof wall and floor wall through dynamic balance, and covers the gaps between the sidewall and roof and the sidewall and floor formed by the movement of rock strata and deformation of support structure in a flexible manner without physical contact, forming an air pressure barrier that blocks the exchange of airflow.

[0015] Furthermore, gob-side entry includes top-cutting gob-side entry or filling gob-side entry.

[0016] Furthermore, the pillarless mining of the roof-cutting and goaf-retaining roadway includes: 1) Before mining, the roadway is reinforced with constant resistance large deformation anchor cables in advance, and bidirectional shaped charge blasting holes are constructed along the roadway. Pre-splitting blasting is carried out in front of the working face to form a roof-cutting line. After the advance cutting is completed, the working face begins to advance; 2) During the working face advance, in the temporary sealing area of ​​the roof-cutting and roadway formation, the retaining rod support is carried out in a timely manner using a combination of single hydraulic props and U-shaped steel. A rotating wind field generator is laid between the retaining rod support and the goaf to temporarily seal the goaf; 3) During the working face advance, in the permanent spraying and sealing area of ​​the roof-cutting and roadway formation, the goaf on the side of the goaf-retaining roadway is sprayed and sealed to form a sealed wall.

[0017] Furthermore, the pillarless mining with gob-side entry includes: during the mining of the working face, as the working face advances, the gob-side entry filling technology is used to pour back the filling wall. After the filling wall is constructed, a rotary ventilation generator is immediately installed. The construction distance of the filling wall closely follows the advance distance of the working face. Specifically, as the working face advances, the filling wall pouring operation is carried out simultaneously on the side of the newly exposed gob area. After the filling wall in a certain area is poured and initially solidified, a rotary ventilation generator is immediately installed in the gob-side entry outside the filling wall section.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects: 1) The rotating ventilation method used in this invention to control the combined gas and fire disasters in the goaf of the roadway along the goaf effectively reduces the gas concentration in the upper corner of the working face by means of Y-shaped ventilation and the arrangement of rotating ventilation.

[0019] 2) The method of the present invention increases the airflow energy along the goaf and reduces the energy difference between the roadway and the goaf, thus achieving the effect of pressurization, plugging and disaster control.

[0020] 3) The rotating wind field in the method of the present invention generates airflows pointing towards the sidewalls, roof, and floor respectively, which can directly block or even isolate the three-dimensional air leakage flow field along the roadway, thereby achieving the effect of increasing the wall's resistance, plugging leaks, and controlling disasters.

[0021] 4) The power source in the method of the present invention is an underground local fan and ventilation duct, which can make full use of existing equipment, and the overall operation process is less affected by roadway deformation and underground operations. Attached Figure Description

[0022] Figure 1 A schematic diagram of the device layout for controlling the combined gas and fire disasters in the goaf area of ​​the goaf area using a rotating ventilation system under the condition of no coal pillar mining with the roof cut and the goaf left open.

[0023] Figure 2 A schematic diagram of the device layout for controlling the combined gas and fire disasters in the goaf area of ​​the goaf using a rotating ventilation system under the condition of filling the goaf without coal pillars.

[0024] Figure 3 A schematic diagram illustrating the principle of leak sealing and disaster control in a rotating wind field.

[0025] Figure 4 This is a schematic diagram of the rotating wind field generator.

[0026] Figure 5 This is a cross-sectional schematic diagram of a rotating wind field generator.

[0027] In the diagram: 1-Transport roadway, 2-Track roadway, 3-Return airway along the goaf, 4-Return airway of the next working face, 5-Local fan, 6-Ventilation duct, 7-Rotating ventilation generator, 8-Temporary sealing area for roof cutting, 9-Permanent spraying and sealing area for roof cutting, 10-Filling wall, 11-Main ventilation duct, 12-Pipe clamp, 13-Circular air outlet, 13.1-Upper air outlet, 13.2-Right air outlet, 13.3-Lower air outlet, 13.4-Left air outlet, 14-Fixed mining face, 15-Lower fixed mining face, 16-Roof cutting line, 17-Goaf. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. 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.

[0029] like Figure 1 , Figure 2 and Figure 3 As shown, the present invention provides a method for controlling the combined gas and fire disasters in goaf areas of goaf-side roadways using a rotating ventilation field. The method includes: setting up a local fan 5 outside the track roadway 2; setting up a rotating ventilation field generating device 7 at a certain distance from the goaf wall in the goaf-side roadway 3 on the return air side; the rotating ventilation field generating device 7 is connected to the local fan 5 through a ventilation duct 6; the local fan 5 provides high-pressure airflow, which is generated by the rotating ventilation field generating device 7 to rotate and advance along the roadway; the centrifugal force of the rotating ventilation field is used to form a high-pressure air ring around the roadway wall; and the high-pressure air ring is used to flexibly seal the roadway walls, roof, and floor of the goaf-side roadway.

[0030] The rotating wind field generating device 7 is described in detail below: like Figure 4 , 5As shown, the rotating wind field generating device 7 includes multiple main wind ducts 11 connected in sequence. The main wind duct is the core carrier for the output of the rotating wind field. Multiple sets of circumferential air outlets 13 are evenly distributed along the axial direction of the main wind duct 11. Each set of circumferential air outlets 13 includes four air outlets arranged circumferentially around the main wind duct 11: upper air outlet 13.1, lower air outlet 13.3, left air outlet 13.4, and right air outlet 13.2. The four air outlets of each set of circumferential air outlets 13 are centered. The symmetrical distribution structure ensures that the airflow intensity remains balanced in all directions as it flows out from around the duct, preventing the rotating wind field from shifting due to excessively strong or weak airflow on one side. This ensures the rotating wind field can rotate stably around the axis of the main duct, with precise and controllable coverage. All four air outlets are connected to the interior of the main duct 11, forming a comprehensive airflow release channel. Compressed air supplied by the local fan 5 is guided through the interior of the main duct 11 and flows out from each outlet, forming a rotating wind field around the main duct 11. The outlets are rectangular, with each outlet forming a 30° angle with the axis of the main duct 11. This angle parameter, verified through fluid dynamics simulation and experiments, guides the airflow to generate an initial rotational torque upon exiting, providing the basic power for the formation of the overall rotating wind field, while ensuring the concentration of airflow output and preventing excessive dispersion. The length and width of the rectangular outlets must match the overall specifications of the main duct, including its diameter, axial length, and internal airflow rate. Specifically, the width of the air outlet is determined based on the diameter of the main air duct, ensuring that the air outlet can fully utilize the circumferential space of the air duct; the length of the air outlet is determined based on the axial length of the main air duct and the number of air outlets on the same side, ensuring that the total flow area of ​​each air outlet matches the airflow rate inside the main air duct. This avoids airflow obstruction and excessive internal pressure due to excessively small air outlets, and also prevents airflow dispersion and insufficient wind field intensity due to excessively large air outlets, ultimately achieving the best balance between airflow output efficiency and wind field stability. The two air outlets on the same side of two adjacent sets of circumferential air outlets on the main air duct 11 have no axial overlap. Specifically, a preset reasonable distance is maintained between the edges of adjacent air outlets of two adjacent sets of circumferential air outlets 13. This distance is determined based on the diameter of the main air duct and the size of the air outlet, ensuring that the airflow from adjacent air outlets does not interfere with each other near the air duct wall, effectively preventing turbulence and ensuring that each airflow can be output independently and stably, improving the overall uniformity of the rotating wind field. The two adjacent main air ducts 11 are detachably connected by pipe clamps 12. The pipe clamps 12 include two semi-circular clamps. The inner wall of the semi-circular clamps is provided with an anti-slip texture layer that is adapted to the outer wall of the main air duct 11. The two ends of the two semi-circular clamps are fastened together by bolts and nuts.

[0031] The number of main wind tunnels can be flexibly configured according to the coverage requirements of the rotating wind field. When the axial length of the application scenario is large, the number of main wind tunnels can be increased to extend the axial coverage length of the wind field; when the axial length of the application scenario is small, the number of main wind tunnels can be reduced.

[0032] Furthermore, such as Figure 3 As shown, the prevention and control method and principle of the present invention are explained in detail below: The airflow trajectory of the rotating wind field is spiral forward and can cover the entire cross-section of the goaf-retention tunnel. The cross-section includes the space area enclosed by the tunnel walls, roof and floor, ensuring no blind spots in airflow coverage. As the rotating wind field continues to advance in the goaf-retention tunnel, the airflow generates centrifugal force radially outward along the tunnel due to the rotational motion. The centrifugal force drives the airflow to diffuse towards the tunnel wall, roof and floor walls. After being blocked by the walls, the airflow gathers around the tunnel walls, forming a continuous and unbroken high-pressure air ring around the entire circumference of the tunnel.

[0033] The air pressure of the high-pressure air ring is kept in balance with the air pressure of the external environment of the roadway, and the air pressure is evenly distributed along the circumference of the roadway, forming a dynamic balance between the roadway wall and the high-pressure air ring. The high-pressure air ring is closely attached to the sidewall, roof wall and floor wall through dynamic balance, and covers the gaps between the sidewall and roof and the sidewall and floor formed by the movement of rock strata and deformation of support structure in a flexible manner without physical contact, forming an air pressure barrier that blocks the exchange of airflow.

[0034] Furthermore, the aforementioned goaf retention includes top-cutting goaf retention or filling goaf retention, as detailed below.

[0035] The pillarless mining of the roof-cutting and goaf-retaining roadway includes: 1) Before mining, the roadway is reinforced with constant resistance large deformation anchor cables in advance, and bidirectional energy-concentrating blasting holes are constructed along the roadway. Pre-splitting blasting is carried out in front of the working face to form a roof-cutting line 16. After the advance cutting is completed, the working face begins to advance; 2) During the working face advance, in the temporary sealing area 8 of the roof-cutting and roadway formation, the retaining rod is supported in a timely manner by combining single hydraulic props and U-shaped steel. A rotating wind field generator 7 is laid between the retaining rod support and the goaf to temporarily seal the goaf; 3) During the working face advance, in the permanent spraying and sealing area 9 of the roof-cutting and roadway formation, the goaf on the side of the goaf-retaining roadway is sprayed and sealed to form a sealed wall.

[0036] Pillarless mining with gob-side entry retaining includes: during the working face mining, as the working face advances, a backfill wall 10 is poured using gob-side entry retaining backfilling technology. Immediately after the backfill wall 10 is constructed, a rotary ventilation generator 7 is deployed. The construction distance of the backfill wall 10 closely follows the working face advancement distance. Specifically, as the working face advances, the backfill wall 10 pouring operation is carried out simultaneously on the newly exposed gob side. After the backfill wall 10 in a certain area is poured and initially solidified, a rotary ventilation generator 7 is immediately deployed in the gob-side entry retaining backfilling outside that section of the backfill wall 10.

[0037] The following two specific embodiments further illustrate the above-mentioned technical solution of the present invention: Example 1

[0038] Methods for controlling combined gas and fire hazards in goaf areas under the condition of roof-cutting and goaf-retaining roadway mining without coal pillars, such as: Figure 1 As shown, it includes: S1. Two adjacent working faces are excavated, such as Figure 1 The diagram shows the fixed mining face 14, the lower fixed mining face 15, the return airway 4 of the next working face, the roof cutting line 16, and the goaf 17.

[0039] S2. Before mining, constant resistance large deformation anchor cables are constructed in advance to reinforce the roadway. Bidirectional shaped charge blasting holes are constructed along the roadway. Pre-splitting blasting is carried out in front of the working face to form a cutting line 16 that cuts off the roof. After the advance cutting is completed, the working face begins to advance.

[0040] S3. During the advance of the working face, in the temporary sealing area 8 of the roof cutting and roadway formation, the retaining rod support is promptly carried out by combining single hydraulic props and U-shaped steel. A rotating wind field generator 7 is laid between the retaining rod support and the goaf to temporarily seal the goaf.

[0041] S4. During the working face advance, in the permanent spraying and sealing area 9 of the cut-off roadway, spraying and sealing are carried out on the goaf area along the roadway to form a sealed wall.

[0042] S5. During the mining process, a Y-shaped ventilation method is adopted, with air intake via transport roadway 1 (with gob-side roadway retention on the air intake side) and track roadway 2, and return air via gob-side roadway 3.

[0043] S6. Repeat this operation until the working face mining is completed. Example 2

[0044] Methods for controlling combined gas and fire hazards in goaf areas using rotating ventilation systems under the condition of pillarless mining with backfilling and roadway retention, such as... Figure 2 As shown, it includes: S1. Two adjacent working faces are excavated, such as Figure 2The diagram shows the fixed mining face 14, the lower fixed mining face 15, the return airway 4 of the next working face, the roof cutting line 16, and the goaf 17.

[0045] S2. During the mining of this working face, as the working face advances, the filling wall 10 is poured using the goaf retention filling technology. After the filling wall 10 is constructed, the rotating wind field generator 7 is immediately deployed. The construction distance of the filling wall 10 closely follows the advance distance of the working face.

[0046] S3. During the mining process, a Y-shaped ventilation method is adopted, which uses the transport roadway 1 (with the roadway along the goaf on the air intake side) and the track roadway 2 for air intake, and the roadway along the goaf on the return side for air return.

[0047] S4. Repeat this operation until the working face mining is completed.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling combined gas and fire disasters in goaf areas along roadways using rotating wind fields, characterized in that: A local fan (5) is installed outside the track roadway (2), and a rotating air field generator (7) is installed in the return air side goaf retainer (3). The rotating air field generator (7) is connected to the local fan (5) through the air duct (6). The local fan (5) provides high-pressure airflow, which is generated by the rotating air field generator (7) to rotate and advance along the roadway. The centrifugal force of the rotating air field is used to form a high-pressure air ring around the roadway wall. The high-pressure air ring is used to flexibly seal the roadway side, roof and floor of the goaf retainer.

2. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field, as described in claim 1, is characterized in that: The rotating wind field generating device (7) includes multiple main air ducts (11) connected in sequence. Multiple sets of circumferential air outlets are evenly distributed along the axial direction of the main air duct (11). Each set of circumferential air outlets includes four air outlets arranged along the circumference of the main air duct (11): upper, lower, left, and right. The four air outlets are centrally symmetrically distributed. All four air outlets are connected to the interior of the main air duct (11) to form an all-round airflow release channel. The compressed air provided by the local fan (5) is guided through the interior of the main air duct (11) and flows out from each air outlet to form a rotating wind field around the main air duct (11).

3. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field, as described in claim 2, is characterized in that: The air outlet has a rectangular structure, and the included angle between each air outlet and the axis of the main air duct (11) is set to 30°.

4. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field, as described in claim 3, is characterized in that: The two air outlets on the same side of two adjacent sets of circumferential air outlets on the main air duct (11) are in an area where there is no axial overlap.

5. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field according to claim 4, characterized in that: The two adjacent main air ducts (11) are detachably connected by a pipe clamp (12). The pipe clamp (12) includes two semi-circular ring clamps. The inner wall of the semi-circular ring clamp is provided with an anti-slip texture layer that is compatible with the outer wall of the main air duct (11). The two ends of the two semi-circular ring clamps are fastened together by bolts and nuts.

6. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field according to claim 5, characterized in that: The airflow trajectory of the rotating wind field is spiral forward and can cover the entire cross-section of the goaf-retention tunnel. The cross-section includes the space area enclosed by the tunnel walls, roof and floor, ensuring no blind spots in airflow coverage. As the rotating wind field continues to advance in the goaf-retention tunnel, the airflow generates centrifugal force radially outward along the tunnel due to the rotational motion. The centrifugal force drives the airflow to diffuse towards the tunnel wall, roof and floor walls. After being blocked by the walls, the airflow gathers around the tunnel walls, forming a continuous and unbroken high-pressure air ring around the entire circumference of the tunnel.

7. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field, as described in claim 5, is characterized in that: The air pressure of the high-pressure air ring is kept in balance with the air pressure of the external environment of the roadway, and the air pressure is evenly distributed along the circumference of the roadway, forming a dynamic balance between the roadway wall and the high-pressure air ring. The high-pressure air ring is closely attached to the sidewall, roof wall and floor wall through dynamic balance, and covers the gaps between the sidewall and roof and the sidewall and floor formed by the movement of rock strata and deformation of support structure in a flexible manner without physical contact, forming an air pressure barrier that blocks the exchange of airflow.

8. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field according to claim 5, characterized in that: Goaf retention includes goaf retention by cutting the top or goaf retention by filling.

9. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field, as described in claim 8, is characterized in that: The pillarless mining of the top-cutting and goaf-retaining roadway includes: 1) Before mining, the roadway is reinforced with constant resistance large deformation anchor cables in advance, and bidirectional energy-concentrating blasting holes are constructed along the roadway. Pre-splitting blasting is carried out in front of the working face to form a top-cutting line (16) that cuts off the roof. After the advance cutting is completed, the working face begins to advance; 2) During the working face advance, in the temporary sealing area of ​​the top-cutting roadway (8), the retaining rod is supported in a timely manner by combining single hydraulic props and U-shaped steel. A rotating wind field generator (7) is laid between the retaining rod support and the goaf to temporarily seal the goaf; 3) During the working face advance, in the permanent spraying and sealing area of ​​the top-cutting roadway (9), the goaf on the side of the goaf-retaining roadway is sprayed and sealed to form a sealed wall.

10. The method for controlling combined gas and fire disasters in goaf areas along the goaf using a rotating wind field according to claim 8, characterized in that: The coal pillarless mining with gob-side entry includes: during the mining of the working face, as the working face advances, the gob-side entry filling technology is used to pour the filling wall (10), and immediately after the filling wall (10) is constructed, the rotating wind field generator (7) is installed. The construction distance of the filling wall (10) closely follows the working face advance distance.

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