CN115625053A

CN115625053A - Method for improving gas concentration by spraying, plugging and plugging coal wall and spraying device

Info

Publication number: CN115625053A
Application number: CN202211280076.5A
Authority: CN
Inventors: 纪宝柱; 胡继龙; 黄钧泽; 徐同辉; 葛进贤; 陈伟; 杜旭; 方震; 刘伟
Original assignee: Anhui Bozhou Coal Industry Co ltd
Current assignee: Anhui Bozhou Coal Industry Co ltd
Priority date: 2022-10-19
Filing date: 2022-10-19
Publication date: 2023-01-20
Anticipated expiration: 2042-10-19
Also published as: CN115625053B

Abstract

The invention relates to the field of coal wall spraying equipment, in particular to a method for increasing gas concentration by coal wall spraying plugging and a spraying device, which comprise a spraying gun body, wherein one end of the spraying gun body is provided with an air spraying structure, the spraying gun body is internally provided with a spraying cavity, the spraying cavity penetrates through one end close to the air spraying structure, an adjusting valve is arranged in the spraying cavity, the adjusting valve comprises a valve shell, a valve groove is arranged in the valve shell, a valve core is adapted to be matched in the valve groove through a spring, the surface of the valve groove is provided with two agent guiding ports, a second air port and a first air port, which penetrate through the valve groove, the two agent guiding ports are arranged in a lifting sliding way along the sliding direction of the valve core, the agent valve port and the agent guiding port are aligned, the air valve port and the second air port are aligned, so that the coal wall spraying is realized, when the air port and the first air port are aligned by adjustment, gas is guided into the spraying cavity, the residual mixed agent is sprayed out at high pressure, and the blockage caused by the residual mixed spraying agent in the spraying cavity and the port is avoided.

Description

Method for improving gas concentration by spraying, plugging and plugging coal wall and spraying device

Technical Field

The invention relates to the field of coal wall spraying equipment, in particular to a method for stopping leakage and improving gas concentration by spraying a coal wall and a spraying device.

Background

The gas is a main subsidiary product in coal mining, has influence on the safety production of coal mines, is a main greenhouse gas, and has much more capability of generating greenhouse effect than CO ₂ The gas is a disaster factor in coal mining and is a high-efficiency clean energy, so that the coal mine is required to extract gas as much as possible while mining, namely 'coal and gas co-extraction' is performed, but the gas extraction efficiency is very low in the world range under the current technical conditions, the mine gas extraction rate is low not only because the coal seam in China generally has the characteristics of high metamorphism degree, low permeability and low gas saturation, but also an important reason is that air is mixed into an extraction drill hole along the fracture of the coal wall, so that the concentration of extracted gas is low, and the actual conditions restrict the development and utilization of the coal seam gas in China;

the method for spraying the coating on the surface of the coal wall generally adopts an organic polymer two-liquid type foaming agent as the coating, a spraying device is adopted to mix two components of the polyurethane combined foaming material to completely cover the section of the whole roadway side, the mixed two components of the foaming agent are quickly foamed and formed into the plugging wall on the surface of the coal wall, the cracks of the coal wall are effectively solidified and filled, the air permeability coefficient of the surface layer of the coal wall can be reduced, and the gas extraction concentration is improved;

the two-component organic foaming material is sprayed out after being mixed in a spraying gun, and the organic foaming mixture is easy to remain in a spray gun port after spraying is stopped, so that foaming and expansion are carried out in the spray gun port, and if the foaming material in the spray gun port is solidified due to long spraying stopping time, spraying blockage can be caused, and the reuse of the spray gun is influenced.

Disclosure of Invention

The invention aims to solve the following problems in the prior art: the two-component organic foaming material is sprayed out after being mixed in a spraying gun, and the organic foaming mixture is easy to remain in a spray gun port after spraying is stopped, so that foaming and expansion are carried out in the spray gun port, and if the foaming material in the spray gun port is solidified due to long spraying stopping time, spraying blockage can be caused, and the reuse of the spray gun is influenced.

In order to solve the problems in the prior art, the invention provides a coal wall spraying device, which comprises a spraying gun body, wherein one end of the spraying gun body is provided with an air spraying structure, a spraying cavity is arranged in the spraying gun body, the spraying cavity penetrates through one end close to the air spraying structure, a regulating valve is arranged in the spraying cavity, the regulating valve comprises a valve shell, a valve groove is formed in the valve shell, a valve core is matched in the valve groove through a spring, the surface of the valve groove is provided with two agent guiding ports penetrating through the valve groove, a second air port and a first air port, the two agent guiding ports and the second air port and the first air port are arranged along the sliding direction of the valve core, the surface of the valve core is provided with two agent valve ports and one air valve port, the agent valve ports are aligned with the agent guiding ports, and the air valve ports are aligned with the second air port and the first air port;

two it spouts the chamber to lead one side intercommunication of agent mouth, and two opposite sides that lead the agent mouth are connected with first feed subassembly, second feed subassembly respectively, one side of second gas port, first gas port is connected with the air feed subassembly jointly, and the chamber is spouted in the other end intercommunication of first gas port, and the other end intercommunication of second gas port spouts the structure, the case is connected with the switch module.

Preferably, the switch component comprises a handle, the handle is fixedly connected with the spray gun body, one end of the handle close to the spray gun body is elastically rotated through a torsion spring to form a holding rod, a sliding groove is formed in the surface of the handle, a sliding block slides in the sliding groove, the sliding block is rotatably connected with a connecting rod, the connecting rod is rotatably connected with the holding rod, a steel wire is fixed on the sliding block, and the steel wire is connected with the end portion of the valve core.

Preferably, the bottom of the valve housing and the top of the holding rod are provided with guide wheels, and the steel wire bypasses the guide wheels to connect the valve core and the sliding block.

Preferably, the top of the valve core is provided with a sealing cavity, a stop block is matched with the inside of the sealing cavity in a sliding manner, a through hole which is communicated from top to bottom is formed in the surface of the stop block, a needle rod is fixed on the stop block, the needle rod penetrates through the sealing cavity in a sliding manner to be fixedly connected with the top of the valve groove, and damping liquid is filled in the sealing cavity.

Preferably, two sets of lead the one end of agent mouth to communicate respectively has first agent pipe, second agent pipe, and first agent pipe, second agent bobbin hose are connected first feeding subassembly, second feeding subassembly respectively, and the one end of two sets of agent mouths of leading is link up through leading the agent pipe and is spouted the chamber, the air supply pipe is connected jointly to one side of second gas port, first gas port, one side, the air supply pipe is connected with air supply subassembly, and the chamber is spouted through first trachea intercommunication to the first gas port other end, and the second gas port other end is through second trachea intercommunication gas-blast structure.

Preferably, it has the siphunculus to spout the sealed rotation in chamber middle part, and the periphery of siphunculus has the annular, and the siphunculus outer wall has the petiole of adaptation in the annular, and the siphunculus inner wall has stirs the handle, the second trachea is along the tangential direction and the annular intercommunication of annular, and the edge tangential intercommunication of annular has the third trachea, and third trachea and air blast structure intercommunication.

Preferably, the air blast structure includes the air duct, and the air duct intercommunication third trachea, the tip of the spray gun body have toper recessed mouthful, around a plurality of outer ring gas pockets, the inner ring gas pocket of angular ring such as toper recessed mouthful, outer ring gas pocket, inner ring gas pocket intercommunication the air duct, the tip in spray chamber is the toper and reduces the central point that communicates at toper recessed mouthful and put.

The method for improving the gas concentration by coal wall spraying plugging based on the spraying device comprises the following specific steps:

A. the first feeding assembly and the second feeding assembly respectively pressurize the two agent guiding ports to provide two groups of foaming agents, and the gas supply assembly conducts high-pressure gas to the second gas port and the first gas port;

B. the valve core is pulled by the switch assembly to overcome the elastic force and descend, so that the two agent valve ports are aligned with the two agent guide ports, the air valve port is aligned with the second air port, the two groups of foaming agents are guided into the spray cavity to be mixed to form a mixed agent and are sprayed out from the end part of the spray cavity, and high-pressure air is sprayed to the mixed agent through the air spraying structure, so that the sprayed mixed agent is atomized;

C. when the spraying is stopped, the valve core is reset to align the air valve port with the first air port through the loosening of the switch assembly, the second air port and the agent guiding port are blocked at the moment, and high-pressure air is guided into the spraying cavity through the first air port to spray the rest of the mixed agent, so that the spraying cavity and the port thereof are kept smooth.

Compared with the related technology, the method for improving the gas concentration by spraying, plugging and leaking the coal wall and the spraying device provided by the invention have the following beneficial effects:

1. according to the invention, the valve core is lifted and slides in the valve groove, so that the agent valve port and the agent guide port are aligned, and the gas valve port and the second gas port are aligned, so that seam filling spraying on the coal wall is realized, the valve core is adjusted to move, and when the gas valve port is aligned with the first gas port, gas is guided into the spraying cavity, and residual mixing agent is sprayed out at high pressure, so that the blockage of the inside of the spraying cavity and the port caused by foaming of the residual mixing spraying agent is avoided;

2. according to the invention, the second air pipe is adopted to introduce high-pressure air along the tangential direction of the annular groove until the third air pipe is discharged, so that the petioles are driven by the air flow to drive the through pipe and the stirring handle to rotate, the two-component spraying agent in the spraying cavity is fully mixed, the spraying agent can be quickly foamed and shaped after being sprayed, and the action generating efficiency of the spraying agent is improved.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of the structure of the spray gun of the present invention;

FIG. 3 is a schematic view of the distribution structure of the air-jet structure, the spray gun and the regulating valve of the present invention;

FIG. 4 is a schematic structural view of the air-jet structure of the present invention;

FIG. 5 is a schematic view of a connection structure of the first air tube and the second air tube according to the present invention;

FIG. 6 is a schematic view of the connection structure of the second air tube, the third air tube and the ring groove of the present invention;

FIG. 7 is a schematic view of the piping connection structure of the regulating valve of the present invention;

FIG. 8 is a schematic view of the external structure of the regulator valve of the present invention;

FIG. 9 is a schematic view of the internal structure of the regulator valve of the present invention;

FIG. 10 is a schematic view of the internal structure of the valve cartridge of the present invention;

fig. 11 is a schematic structural diagram of the switch assembly of the present invention.

Reference numbers in the figures: 1. a first supply assembly; 2. a second supply assembly; 3. a gas supply assembly; 4. a spray gun body; 5. a switch assembly; 51. a handle; 52. a chute; 53. a slider; 54. a holding rod; 55. a connecting rod; 56. a steel wire; 6. a first dose tube; 7. a second dose tube; 8. a gas supply pipe; 9. adjusting a valve; 91. a valve housing; 92. a valve core; 93. a valve spool; 94. a guiding agent port; 95. a second air port; 96. a first air port; 97. a valve port; 98. an air valve port; 99. sealing the cavity; 910. a stopper; 911. a port; 912. a needle bar; 10. pipe passing; 11. a petiole; 12. a ring groove; 13. an air tank; 14. an outer ring air hole; 15. an inner ring air hole; 16. a spray chamber; 17. a catheter; 18. a first air pipe; 19. a second air pipe; 20. a third air pipe; 21. and (4) stirring the handle.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.

Specific implementations of the present invention are described in detail below with reference to specific embodiments.

Example one

As shown in figure 1, the coal wall spraying device consists of three parts, namely an agent supply part, an air supply part and a spray gun;

the structure of the donor part is as follows:

the first feeding component 1 and the second feeding component 2 can be high-pressure finished product filling components of two organic combined foaming materials;

the first feeding assembly 1 and the second feeding assembly 2 can also be two independent containers, a liquid pump is arranged outside the containers, the liquid inlet end of the liquid pump is connected with the inside of the containers, and the liquid discharge end of the liquid pump is connected with a spray gun through a hose;

the gas supply part has the following structure:

the air supply component 3 can be an independent booster pump or other devices for outputting air with stable pressure, but a moisture filter is arranged at the air exhaust end and is connected with a spray gun through a hose;

two hoses of the foaming agent and the air supply hose need to be bound to form an independent soft conducting line, so that messy pipelines are avoided, and the operation is difficult;

the structure of the spray gun part is as follows:

as shown in fig. 3 and 4, the spray gun body 4 is a cylinder, a cylindrical spray cavity 16 is arranged inside the spray gun body 4, the end part of the spray cavity 16 is tapered and reduced to be communicated with the center of the front end of the spray gun body 4, an air spraying structure is arranged at the front end of the spray gun body 4, the air spraying structure comprises an annular air groove 13, the front end surface of the spray gun body 4 is provided with a tapered recess, a plurality of outer ring air holes 14 and inner ring air holes 15 are annularly distributed around the tapered recess at equal angles, and the outer ring air holes 14 and the inner ring air holes 15 are communicated with the air groove 13;

as shown in fig. 1, 2 and 3, a first agent pipe 6, a second agent pipe 7 and an air supply pipe 8 are embedded and fixed at the tail part of the spray gun body 4, two hoses of the first feeding assembly 1 and the second feeding assembly 2 are connected with the end parts of the first agent pipe 6 and the second agent pipe 7, and a hose of the air supply assembly 3 is connected with the air supply pipe 8;

as shown in fig. 5, 8 and 9, an upward square groove is formed in the bottom of the spray gun body 4, the regulating valve 9 is adapted to penetrate into the square groove from bottom to top, and the regulating valve 9 is fixed in the square groove from the spray gun body 4 by using a screw, the regulating valve 9 comprises a valve casing 91, a valve groove 93 is formed in the valve casing 91, a valve core 92 is slidably adapted in the valve groove 93, the valve core 92 can slidably lift in the valve groove 93, a spring is mounted at the bottom of the valve core 92, two groups of agent guide ports 94, a second air port 95 and a first air port 96 are formed in the surface of the valve casing 91, the agent guide ports 94, the second air port 95 and the first air port 96 are communicated with the valve groove 93, the two groups of agent guide ports 94 are vertically distributed, the first air port 96 and the second air port 95 are vertically distributed, two agent ports 97 and an air port 98 are formed in the surface of the valve core 92, the agent port 97 is aligned with the agent guide port 94, and the agent port 98 is aligned with the second air port 95 and the first air port 96;

as shown in fig. 3, 5 and 7, the first agent pipe 6 and the second agent pipe 7 are respectively communicated with the rear ends of the agent introduction ports 94, the air supply pipe 8 has two branch ends which are respectively connected with the rear ends of the second air port 95 and the first air port 96, the front ends of the two agent introduction ports 94 are communicated with the spray cavity 16 through the agent introduction pipe 17, the first air port 96 is communicated with the spray cavity 16 through the first air pipe 18, and the second air port 95 is communicated with the air groove 13 through the second air pipe 19;

as shown in fig. 11, the switch assembly 5 includes a handle 51, the handle 51 is fixedly connected to the gun body 4, a holding rod 54 is elastically and rotatably mounted on a portion of the handle 51 close to the gun body 4 through a torsion spring, a sliding groove 52 is formed in a surface of the handle 51, a sliding block 53 is slidably mounted in the sliding groove 52, the sliding block 53 is rotatably connected to a connecting rod 55, the connecting rod 55 is rotatably connected to the holding rod 54, guide wheels are respectively provided at a bottom of the valve housing 91 and a top of the holding rod 54, and the steel wire 56 is connected to the valve core 92 and the sliding block 53 by bypassing the guide wheels;

when spraying is carried out:

the handle 51 is held by hand, the holding rod 54 is closed, the connecting rod 55 is pushed to swing to enable the sliding block 53 to slide downwards along the sliding groove 52, the steel wire 56 is pulled to enable the valve core 92 to slide downwards in the valve groove 93 by overcoming elasticity, the two agent valve ports 97 are aligned with the two agent guide ports 94, the air valve port 98 is aligned with the second air port 95, the spraying foaming components provided by the first material supplying component 1 and the second material supplying component 2 are guided into the spraying cavity 16 through the agent guide pipe 17 to be mixed and are sprayed out from the tip end of the spraying cavity 16, the high-pressure air provided by the air supplying component 3 is guided into the air groove 13 through the second air pipe 19 and then is sprayed out from the outer ring air hole 14 and the inner ring air hole 15, and the sprayed mixed spraying agent is atomized by the sprayed out gas and acts on the surface of the coal wall to form a leakage blocking layer;

stopping spraying and cleaning the gun:

as shown in fig. 11, the holding rod 54 is not completely loosened, the slider 53 is reset for a certain distance, the valve core 92 is lifted by the elastic force until the air valve port 98 is aligned with the first air port 96, at this time, the agent guiding port 94 and the second air port 95 are plugged in a staggered manner, high-pressure air is guided into the spraying cavity 16 through the first air port 96 and the first air pipe 18, the residual mixing agent in the spraying cavity 16 is sprayed out at high pressure, then the holding rod 54 is completely loosened, the first air port 96 is also plugged, and the blockage of the inside and the port of the spraying cavity 16 due to the foaming of the residual mixing spraying agent is avoided;

as shown in fig. 10, a sealing cavity 99 is formed at the top of the valve core 92, a stopper 910 is vertically and slidably fitted inside the sealing cavity 99, a plurality of through ports 911 which are communicated up and down are formed in the surface of the stopper 910, a needle rod 912 is fixed on the stopper 910, the needle rod 912 slides out of the sealing cavity 99 and is fixedly connected with the top of the valve groove 93, and damping fluid is filled in the sealing cavity 99;

when the valve core 92 is driven to move downwards to open the spraying pipeline, the stopper 910 moves upwards relatively in the sealed cavity 99, damping fluid needs to pass through the through hole 911, damping force is generated to slow down the valve core 92, the time for the agent valve port 97 to pass through the first air port 96 is prolonged, when the agent valve port 97 passes through the first air port 96, gas is guided into the spraying cavity 16 for cleaning before spraying, and when the valve core 92 is closed by moving upwards, the coincidence time of the agent valve port 97 and the first air port 96 is prolonged, and the gas blowing cleaning of the spraying cavity 16 is carried out.

Example two

As shown in fig. 3, 5 and 6, a rotating through pipe 10 is sealed in the middle of a spray cavity 16, the inner cavity of the through pipe 10 and the spray cavity 16 form a complete conduction space, a ring groove 12 is formed in the periphery of the through pipe 10, a plurality of blade handles 11 are annularly distributed on the outer wall of the through pipe 10, the blade handles 11 are adapted in the ring groove 12, an agitating handle 21 is arranged on the inner wall of the through pipe 10, a second air pipe 19 is communicated with the ring groove 12 along the tangential direction of the ring groove 12, a third air pipe 20 is tangentially communicated with the edge of the ring groove 12, and the third air pipe 20 is communicated with an air spray structure;

when spraying is carried out, high-pressure air is tangentially introduced into the annular groove 12 through the second air pipe 19, the leaf handle 11 is impacted by the high-pressure air to drive the through pipe 10 to rotate, the high-pressure air is discharged from the third air pipe 20 and introduced into the air groove 13, the rotating through pipe 10 enables the stirring handle 21 in the through pipe to mix the two-component spraying agent in the spraying cavity 16, the two-component spraying agent is fully combined and can be quickly foamed and shaped after being sprayed out, and the effect generating efficiency of the spraying agent is improved;

EXAMPLE III

A. the first feeding assembly 1 and the second feeding assembly 2 respectively pressurize the two agent guiding ports 94 to provide two groups of foaming agents, and the gas supply assembly 3 transmits high-pressure gas to the second gas port 95 and the first gas port 96;

B. the valve core 92 is pulled by the switch component 5 to overcome the descending of the elastic force, so that the two groups of agent valve ports 97 are aligned with the two groups of agent guide ports 94, the air valve ports 98 are aligned with the second air ports 95, two groups of foaming agents are guided into the spraying cavity 16 to be mixed to form a mixed agent and are sprayed out from the end part of the spraying cavity 16, high-pressure air is sprayed to the mixed agent by the air spraying structure, and the sprayed mixed agent is atomized;

C. when the spraying is stopped, the valve core 92 is reset to align the air valve port 98 with the first air port 96 by loosening the switch component 5, at the moment, the second air port 95 and the agent guiding port 94 are blocked, and high-pressure air is guided into the spraying cavity 16 through the first air port 96 to spray out the rest of the mixed agent, so that the spraying cavity 16 and the ports thereof are kept smooth.

Claims

1. The coal wall spraying device comprises a spraying gun body (4), and is characterized in that one end of the spraying gun body (4) is provided with an air spraying structure, a spraying cavity (16) is arranged in the spraying gun body (4), the spraying cavity (16) penetrates through one end close to the air spraying structure, a regulating valve (9) is arranged in the spraying cavity (16), the regulating valve (9) comprises a valve casing (91), a valve groove (93) is arranged in the valve casing (91), a valve core (92) is fitted in the valve groove (93) through a spring, the surface of the valve groove (93) is provided with two agent guide ports (94) penetrating through the valve groove (93), a second air port (95) and a first air port (96), the two agent guide ports (94) and the second air port (95) and the first air port (96) are arranged along the sliding direction of the valve core (92), the surface of the valve core (92) is provided with two agent valve ports (97) and one air valve port (98), the agent (97) is aligned with the agent guide ports (94), and the air valve port (98) is aligned with the second air port (95) and the first air port (96);

two it spouts chamber (16) to lead one side intercommunication of agent mouth (94), and the opposite side of two leading agent mouths (94) is connected with first feed subassembly (1), second feed subassembly (2) respectively, one side of second gas port (95), first gas port (96) is connected with air feed subassembly (3) jointly, and chamber (16) are spouted in the other end intercommunication of first gas port (96), and the other end intercommunication of second gas port (95) the gas spouts the structure, case (92) are connected with switch module (5).

2. The coal wall spraying device according to claim 1, wherein the switch assembly (5) comprises a handle (51), the handle (51) is fixedly connected with the spray gun body (4), a holding rod (54) is elastically rotated at one end, close to the spray gun body (4), of the handle (51) through a torsion spring, a sliding groove (52) is formed in the surface of the handle (51), a sliding block (53) is arranged in the sliding groove (52), the sliding block (53) is rotatably connected with a connecting rod (55), the connecting rod (55) is rotatably connected with the holding rod (54), a steel wire (56) is fixedly arranged on the sliding block (53), and the steel wire (56) is connected with the end portion of the valve core (92).

3. The coal wall painting device according to claim 2, characterized in that the bottom of the valve casing (91) and the top of the holding rod (54) are provided with guide wheels, and the steel wire (56) bypasses the guide wheels to connect the valve core (92) and the sliding block (53).

4. The coal wall spraying device according to claim 2, characterized in that a sealing cavity (99) is formed in the top of the valve core (92), a stop block (910) is slidably fitted in the sealing cavity (99), a through hole (911) which is communicated up and down is formed in the surface of the stop block (910), a needle rod (912) is fixed to the stop block (910), the needle rod (912) slidably penetrates through the sealing cavity (99) and is fixedly connected to the top of the valve groove (93), and damping liquid is filled in the sealing cavity (99).

5. The coal wall spraying device according to claim 1, wherein one end of each of the two groups of agent guide ports (94) is communicated with a first agent pipe (6) and a second agent pipe (7), the first agent pipe (6) and the second agent pipe (7) are respectively connected with a first feeding assembly (1) and a second feeding assembly (2), one end of each of the two groups of agent guide ports (94) penetrates through the spraying cavity (16) through the agent guide pipe (17), one side of each of the second air port (95) and the first air port (96) is commonly connected with the air supply pipe (8), the air supply pipe (8) is connected with the air supply assembly (3), the other end of the first air port (96) is communicated with the spraying cavity (16) through the first air pipe (18), and the other end of the second air port (95) is communicated with the air spraying structure through the second air pipe (19).

6. The coal wall spraying device according to claim 5, characterized in that a through pipe (10) is hermetically rotated in the middle of the spraying cavity (16), a ring groove (12) is formed in the periphery of the through pipe (10), a blade handle (11) matched with the ring groove (12) is arranged on the outer wall of the through pipe (10), a stirring handle (21) is arranged on the inner wall of the through pipe (10), the second air pipe (19) is communicated with the ring groove (12) along the tangential direction of the ring groove (12), a third air pipe (20) is communicated with the edge of the ring groove (12) in the tangential direction, and the third air pipe (20) is communicated with the air spraying structure.

7. The coal wall spraying device according to claim 6, characterized in that the air injection structure comprises an air groove (13), the air groove (13) is communicated with the third air pipe (20), the end of the spray gun body (4) is provided with a conical recessed port, a plurality of outer annular air holes (14) and inner annular air holes (15) are annularly distributed around the conical recessed port at equal angles, the outer annular air holes (14) and the inner annular air holes (15) are communicated with the air groove (13), and the end of the spray cavity (16) is in conical reduced communication at the center of the conical recessed port.

8. The method for increasing the gas concentration through coal wall spraying leakage stoppage based on the spraying device as claimed in any one of claims 1 to 7 is characterized by comprising the following specific steps:

A. the first feeding assembly (1) and the second feeding assembly (2) respectively pressurize the two agent guiding openings (94) to provide two groups of foaming agents, and the air supply assembly (3) transmits high-pressure air to the second air opening (95) and the first air opening (96);

B. the valve core (92) is pulled by the switch component (5) to overcome the descending of elastic force, so that two agent valve ports (97) are aligned with two agent guide ports (94), the air valve port (98) is aligned with the second air port (95), two groups of foaming agents are guided into the spray cavity (16) to be mixed to form a mixed agent and are sprayed out from the end part of the spray cavity (16), high-pressure air is sprayed to the mixed agent by the air spraying structure, and the sprayed mixed agent is atomized;

C. when the spraying is stopped, the valve core (92) is reset to the state that the air valve port (98) is aligned with the first air port (96) through loosening of the switch assembly (5), the second air port (95) and the agent guide port (94) are blocked, and high-pressure air is guided into the spraying cavity (16) through the first air port (96) to spray out the residual mixing agent, so that the spraying cavity (16) and the port thereof are kept smooth.