Tunnel dust removal system and dust removal method thereof

Abstract

A tunnel dust removal system and a dust removal method thereof are provided. The tunnel dust removal system includes an air blower 1, a whirl suction device 4, a dust removal device 5, an extraction f

Description

TECHNICAL FIELD

[0001] The present invention relates to the technical field of tunneling, in particular to a tunnel dust removal system and a dust removal method thereof. BACKGROUND

[0002] Due to the advantages of significantly shortening transport lines and saving cultivated land in tunnel construction, tunnels are common building facilities in traffic engineering.

[0003] A large amount of dust can be produced during tunnel construction with drilling and blasting method. Excessive dust in the construction tunnel is not conducive to construction and also harmful to the health of workers. At present, the basic dust removal methods commonly used in tunnel construction include natural settlement method, wind discharge method and water spray settlement method. The natural settlement method is a method that after blasting, construction personnel evacuate the work area and wait for a large amount of dust to settle on a tunnel floor by gravity before starting construction. The method requires a long settlement time, thus seriously affecting the construction progress. In the wind discharge method, dusty air is discharged from the tunnel by means of blowing ventilation, exhaust ventilation or a combination thereof. However, the air inlet and the air outlet used in this method are far smaller than the tunnel section, so that the produced airflow cannot fill the tunnel space, resulting in low dust removal efficiency. The airflow cannot act on the local tunnel wall in different directions flexibly, comprehensively, and efficiently, so that the dust adhered to the tunnel wall is difficult to fall off. In addition, the direct discharge of dusty airflow from the tunnel entrance causes serious air pollution. In the water spray settlement method, water mist is sprayed into the tunnel space, but the space in which dust is suspended is large and the concentration of dust is high, so a large amount of water is needed to effectively remove dust. Therefore, this method is not suitable for use in water-deficient areas, and is easy to lead to muddy tunnel floor, which is not conducive to workers walking and operating. The mud discharged to the tunnel entrance can cause serious surface pollution.

[0004] At present, mechanical contact, hydraulic or pneumatic methods are usually used for dust removal in operating tunnels. In the mechanical contact method for dust removal, brooms, mops and other tools are mainly used to clean accessible areas, resulting in small dust removal range, low dust removal efficiency, and easy touch damages to electrical facilities. In the hydraulic cleaning method, pressure water flushing is mainly used, which easily leads to humid environment, electric leakage or short circuit of electrical facilities, and even affects the signal transmission and control of trains operating in the tunnel, affecting driving safety. Moreover, cities lacking water cannot bear hydraulic flushing of long-line tunnels. In the pneumatic cleaning method, dusty airflow is often sucked away with negative pressure by virtue of the dust suction device. However, due to the limit requirements of railway vehicle design, the dust suction device mounted on the vehicle has to be far away from the dust removal surface, so that it is difficult to effectively remove dust from the surface of ballast beds and tunnel walls, and even more difficult to realize dust removal in the far space ahead. In addition, electrical facilities are often mounted on the tunnel wall, so that it is difficult for airflow to enter the tunnel wall covered by the electrical facilities, resulting in difficulty in removing dust from the tunnel wall at corresponding surfaces. If manual operation of the dust suction device is adopted, the dust removal efficiency is low because the level of automation is low and the dust removal can only be carried out within the reach of manpower. SUMMARY

[0005] The purpose of the present invention is to provide an environmentally friendly and efficient tunnel dust removal system and a dust removal method thereof which are suitable for both tunnel surface dust removal and tunnel space dust removal.

[0006] The technical solution of the present invention is that: a tunnel dust removal system includes an air blower, a whirl suction device, a dust removal device, an extraction fan, a powerassisting device with an air outlet and an air inlet, and an air curtain device with an air outlet and an air inlet. An outlet of the air blower is in communication with the air inlet of the power-assisting device. The air outlet of the power-assisting device is arranged opposite to the air outlet of the air curtain device. The air blower is integrated and capable of moving as a whole with the powerassisting device, and the air curtain device is integrated and capable of moving as a whole with the whirl suction device, the dust removal device, and the extraction fan. The whirl suction device, the dust removal device and the extraction fan are connected through an air pipeline in sequence, and an air inlet of the whirl suction device is arranged towards the air outlet of the power-assisting device. The extraction fan is in communication with the air inlet of the air curtain device through a return air pipeline, and a tangential air inlet of the whirl suction device is in communication with the extraction fan through the return air pipeline.

[0007] In the above solution, dust adhered to a tunnel wall can be blown off by the power-assisting device independently or cooperatively with whirl suction flow field in the tunnel, the dust suspended in the tunnel can be pushed by the power-assisting device towards the whirl suction device, and then the dust is sucked in by the whirl suction device. After the sucked dust is treated by the dust removal device, cleaned airflow is sent back to the whirl suction device and the air curtain device for reuse, which has the characteristic of integrating surface dust removal with space dust removal and the advantage of energy saving.

[0008] In addition, two integrated and independently mobile bodies are used. On one hand, the power-assisting wind, which consists of radial blowing-assisting wind and longitudinal suctionassisting wind, produced by the power-assisting device is based on the premise that the whirl suction flow field produced by the whirl suction device in the tunnel is not weakened. On the other hand, in case that the longitudinal wind produced by the power-assisting device cannot effectively send dust into the whirl suction flow field produced by the whirl suction device in the tunnel, distance between the two mobile bodies should be shortened to realize synergetic dust removal.

[0009] Preferably, blowing-assisting wind produced by a plurality of radial blowing-assisting nozzles connected to a periphery of the power-assisting device through ball joints acts on a tunnel wall so as to help the whirl suction flow field formed by the whirl suction device to drive away dust on the tunnel wall. A plurality of longitudinal suction-assisting nozzles are arranged on the power-assisting device towards a dust suction cylinder to produce suction-assisting wind so as to help the whirl suction flow field formed by the whirl suction device to take away dust suspended in front of the whirl suction device. All the radial blowing-assisting nozzles and all the longitudinal suction-assisting nozzles are provided with switches.

[0010] Generally, the air blower is in an area where dust is to be removed, and the dust removal device is in an area where dust has been removed. The airflow produced by the radial blowingassisting nozzles on the power-assisting device blows off the dust on the wall, and an air curtain produced by the air curtain device prevents the dust from entering one side of the dust removal device where dust has been removed, so that the dust can be collected between the power-assisting device and the whirl suction device for dust removal.

[0011] Preferably, the power-assisting device is mounted on the air blower through a revolute pair. During operation of the longitudinal suction-assisting nozzles, rotation directional of the powerassisting device is consistent with rotation directional of rotating airflow produced by the whirl suction device, which is beneficial for enhancing whirl suction effect of airflow in the tunnel space. The whirl suction device and the power-assisting device are both arranged horizontally so as to ensure that airflow blown out from only the longitudinal suction-assisting nozzles is directed towards the dust suction cylinder on the whirl suction device during non-rotation of the powerassisting device.

[0012] On one hand, outlets of the radial blowing-assisting nozzles can be adjusted to angles opposite to the air outlet of the air curtain device according to requirements, and on the other hand, the outlets of the radial blowing-assisting nozzles can be adjusted to form different angles to radial position lines of the power-assisting device.

[0013] The power-assisting device can rotate clockwise, counterclockwise or alternately according to requirements of dust removal, so that the radial airflow of the power-assisting device can sweep the corresponding entire cross section, or rotate to a certain position and fix the radial nozzles at the best positions, and dust removal is carried out for a long time on the local wall difficult to be cleaned.

[0014] Preferably, the whirl suction device includes a dust suction cylinder and a tornado generator for generating a whirl suction flow field in the dust suction cylinder. The tangential air inlet and a whirl suction device outlet are designed on the tornado generator. The return air pipeline is in communication with the tangential air inlet. The whirl suction device outlet is in communication with the dust removal device.

[0015] Preferably, the tornado generator includes a total circulation channel, a whirl suction flow field generating cylinder, and a plurality of uniformly distributed tangential wind distribution channels. The whirl suction flow field generating cylinder is arranged inside the total circulation channel. The total circulation channel is in communication with the whirl suction flow field generating cylinder through the tangential wind distribution channels. The tangential wind distribution channels provide tangential wind in rotational movement for the whirl suction flow field generating cylinder. The tangential air inlet is in communication with the total circulation channel. An outlet of the whirl suction flow field generating cylinder is provided as the whirl suction device outlet. Under combined action of the tangential wind provided by the tangential wind distribution channels and axial negative pressure produced by the extraction fan, whirl suction airflow spirally moving towards the extraction fan as a whole is generated in the whirl suction flow field generating cylinder.

[0016] Preferably, the dust suction cylinder is in shape of a trumpet, and a larger end of the trumpet is arranged towards the power-assisting device in order to expand the whirl suction flow field formed in the whirl suction flow field generating cylinder into a tunnel, so that the whirl suction flow field spirally advancing towards the dust suction cylinder as a whole is formed in the tunnel. A suitable distance is set between the dust suction cylinder and the power-assisting device under the premise that the whirl suction flow field expanding into the tunnel via the dust suction cylinder is not weakened by the blowing-assisting wind and the suction-assisting wind produced by the power-assisting device. By means of the distance between the dust suction cylinder and the power-assisting device, it is ensured that the whirl suction flow field expanding into the tunnel via the dust suction cylinder is not weakened by the blowing-assisting wind and the suction-assisting wind produced by the power-assisting device.

[0017] Preferably, an air valve is arranged on the return air pipeline, and the air valve is arranged adjacent to the air inlet of the air curtain device.

[0018] The air valve is used for adjusting the airflow in the whirl suction device and the air curtain device. By adjusting opening size of the air valve, the airflow in the return air pipeline is divided into two streams of airflow, one stream of the airflow enters the air curtain device through the air valve, and the other stream of the airflow is fed into the tangential air inlet of the whirl suction device.

[0019] Preferably, the air curtain device includes two cover plates and several support columns spacing the two cover plates. Peripheries of the two cover plates are bent towards the powerassisting device to form an annular groove, and the annular groove is formed as the air outlet of the air curtain device. The annular groove is arranged opposite to the power-assisting device. The radial airflow blown out from the air outlet of the air curtain device forms the air curtain to prevent the dust from diffusing into a tunnel area where the dust removal device is located.

[0020] Due to the design structures of the cover plates and the annular groove of the air curtain device, the airflow blown out from the air curtain device forms an annular air curtain, so that dust is prevented from entering the cleaned area.

[0021] Preferably, included angles between the axes of radial air outlets of the radial blowingassisting nozzles on the power-assisting device and corresponding radial lines on the assisting device during operation are different from each other. Thus, it is ensured that the tunnel wall is subjected to radial wind in different directions.

[0022] The present invention also provides a tunnel dust removal method using the above tunnel dust removal system, including the following steps.

[0023] Making the power-assisting device accept airflow conveyed by the air blower; producing power-assisting wind, i.e., blowing-assisting wind and suction-assisting wind, from the powerassisting device; the blowing-assisting wind is used for helping whirl suction flow field in a tunnel to drive away dust on a tunnel wall while the suction-assisting wind is used for helping the whirl suction flow field in the tunnel to force dust suspended in the tunnel into the dust suction cylinder.

[0024] Producing an air curtain from the air curtain device to prevent the dust from diffusing into a tunnel area where the dust removal device is located.

[0025] Making the whirl suction device produce the whirl suction flow field spirally advancing towards the dust suction cylinder as a whole in the tunnel via the dust suction cylinder to drive away dust adhered on a wall surface and make suspended dust enter the dust suction cylinder.

[0026] Making cleaned airflow treated by the dust removal device enter the return air pipeline by means of the extraction fan, and making a part of the cleaned airflow flow back to the air curtain device to form the air curtain; feeding another part of the cleaned airflow into the tangential air inlet then the total circulation channel to form a rotating airflow.

[0027] Wherein, flow volumes of the air blower and the extraction fan, rotational speed and direction of the power-assisting device, positions of the radial blowing-assisting nozzles, flow rates of the radial blowing-assisting nozzles and the longitudinal suction-assisting nozzles, distance between the power-assisting device and the dust suction cylinder, and flow rate of the air curtain are capable of being controlled, so that synergistic dust removal of a tunnel space and the tunnel wall between the power-assisting device and the whirl suction device is realized.

[0028] Starting the power-assisting device to produce the suction-assisting wind with a corresponding flow rate to assist in forcing suspended dust into the whirl suction device in case that it is difficult to smoothly suck the suspended dust in front of the dust suction cylinder into the whirl suction device by means of the whirl suction flow field expanding into the tunnel via the dust suction cylinder; and starting the power-assisting device to produce the blowing-assisting wind with a corresponding flow rate to drive away dust on the tunnel wall in case that it is difficult to smoothly drive away the dust on the tunnel wall by means of the whirl suction flow field expanding into the tunnel via the dust suction cylinder.

[0029] By means of the suitable distance between the dust suction cylinder and the powerassisting device, it is ensured that the whirl suction flow field expanding into the tunnel via the dust suction cylinder is not weakened by the power-assisting wind produced by the power-assisting device.

[0030] Compared with the prior art, the present invention achieves the following beneficial effects.

[0031] Firstly, the range of application is wide. The tunnel dust removal system can perform large-scale dust removal on the tunnel wall and the tunnel space at the same time, and can be applied to both construction tunnels and operating tunnels.

[0032] Secondly, the dust removal efficiency is high. In the first aspect, the rotating airflow generated by the tornado generator in the whirl suction flow field generating cylinder expands into the tunnel via the dust suction cylinder by means of the internal friction characteristics of the rotating airflow, so that a horizontal artificial tornado which is similar to the natural tornado and spirally moves as a whole, that is, a horizontal whirl suction flow field is formed in the tunnel. Because the dust suction cylinder with a suitable taper is adopted and the air blower is adjusted to produce sufficient air volume, the horizontal artificial tornado can not only act on a far-distance surface of the tunnel with a large cross section, but also fill the entire tunnel space, thus showing a strong integrated dust removal ability for large space and large area. However, negative pressure dust removal can only be used for short-distance surface dust removal or short-distance space dust removal because of rapid decrease of the negative pressure with distance. In the second aspect, the tunnel dust removal system includes the power-assisting device. Due to the radial blowingassisting nozzles mounted on the power-assisting device, it is ensured that dust on local surfaces at various positions and in various shapes on the tunnel wall is effectively taken away by the blowing-assisting airflow through the following two measures. Firstly, the positions of the radial blowing-assisting nozzles can be correspondingly changed according to the local positions and shapes of the tunnel wall by means of the control system. Secondly, the rotational speed and rotational direction of the power-assisting device and the jet speed of the radial blowing-assisting nozzles can be changed, so that the jet velocities in different directions can be gotten. In addition, in case that it is difficult to remove dust at a certain place on the tunnel wall, the power-assisting device can be stopped from rotating, and the airflow in the best orientation can be aimed at the position for a long-term injection until the surface dust removal at that place is completed. In the third aspect, the airflow produced by the longitudinal suction-assisting nozzles mounted on the power-assisting device achieves the following two effects. Firstly, the dust far away from the front of the dust suction cylinder and at the weak place of the whirl suction airflow in the tunnel can be pushed to the dust suction cylinder of the whirl suction device to assist the whirl suction device in completing dust removal. Secondly, with the same rotational direction as the whirl suction airflow, the whirl suction intensity of the airflow and the length of the whirl suction space in the tunnel can be increased. Through the above three measures, the problem that the airflow cannot cover the tunnel surface or fill the tunnel space in the current pneumatic dust removal method of the construction tunnels can be effectively solved, and also the problem that the vehicle-mounted negative pressure dust suction device is far away from the tunnel wall due to the vehicle design limit in the current operating tunnels to result in poor dust suction effect can be solved. In addition, because a mobile dust removal method is adopted, the tunnel dust removal system can realize sectional dust removal under the integrated operation of the surface and space of long tunnels, thus avoiding the disadvantage that it is difficult for the dusty airflow to flow along the tunnel for a long distance. It can be seen that no matter for construction tunnels or operating tunnels, the dust removal effect is obviously increased compared with using traditional dust removal methods.

[0033] Thirdly, the system is energy-saving and environmentally friendly. The tunnel dust removal system includes a return air pipeline, so that the airflow discharged from the extraction fan cannot be directly pushed into the tunnel to build secondary dust in the tunnel and interfere with the whirl suction dust removal flow field, and can be recycled as tangential wind and air curtain wind to realize energy saving. In addition, due to the integration of the dust removal device, the dusty airflow is avoided from being discharged to the atmosphere outside the tunnel, no mud flows to the surface outside the tunnel, so that the system has significant environmental protection advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG. 1 is a schematic diagram of a tunnel dust removal system provided by the present invention;

[0035] FIG. 2 is a structural schematic diagram of a power-assisting device in a non-rotation state along an A-A section view direction in FIG. 1;

[0036] FIG. 3 is a structural schematic diagram of an air curtain device along a B-B section view direction in FIG. 1;

[0037] FIG. 4 is an internal structural schematic diagram of an air curtain device along a D-D section view direction in FIG. 3;

[0038] FIG. 5 is a structural schematic diagram of a tornado generator along a C-C section view direction in FIG. 1;

[0039] FIG. 6 is a working schematic diagram of radial blowing-assisting nozzles and longitudinal suction-assisting nozzles in a non-rotation state of a power-assisting device in a construction tunnel along an A-A section view direction in FIG. 1; and

[0040] FIG. 7 is a working schematic diagram of radial blowing-assisting nozzles and longitudinal suction-assisting nozzles in a non-rotation state of a power-assisting device in a metro operating tunnel along an A-A section view direction in FIG. 1.

[0041] In drawings: 1 air blower; 2 power-assisting device; 21 radial blowing-assisting nozzle; 22 longitudinal suction-assisting nozzle; 23 revolute pair; 3 air curtain device; 31 annular groove; 32 cover plate; 33 support column; 4 whirl suction device; 41 dust suction cylinder; 42 tornado generator; 421 total circulation channel; 422 whirl suction flow field generating cylinder; 423 tangential wind distribution channel; 43 tangential air inlet; 44 whirl suction device outlet; 5 dust removal device; 6 return air pipeline; 61 air valve; 7 extraction fan; 8 lighting lamp; 9 cable; and 10 distribution box. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] The present invention will be described in detail below with reference to the attached figures in conjunction with the embodiments. It needs to be illustrated that under the compatible condition, the embodiments in the present invention and characteristics in the embodiments can be combined mutually. For the convenience of description, if the terms "upper", "lower", "left" and "right" appear below, it just shows that the terms are consistent with the upper, lower, left and right directions of the attached figures, but not limit the structure.

[0043] As shown in FIG. 1, a tunnel dust removal system provided by the embodiment includes an air blower 1, a power-assisting device 2, an air curtain device 3, a whirl suction device 4, a dust removal device 5, an extraction fan 7, and a return air pipeline 6.

[0044] The air blower 1 is integrated and capable of moving as a whole with the power-assisting device 2. Specifically, the air blower 1 is mounted on a mobile trolley. The power-assisting device 2, with a center line of an air outlet of the air blower 1 as an axis, is mounted on an air outlet pipe of the air blower 1 through a revolute pair 23, and a rotation axis of the power-assisting device 2 is approximately parallel to a tunnel floor. An air inlet and an air outlet are formed in the powerassisting device 2, and the air outlet of the air blower 1 is in communication with the air inlet of the power-assisting device 2.

[0045] As shown in FIG. 1 and FIG. 2, multiple radial blowing-assisting nozzles 21 are connected to a periphery of the power-assisting device 2 through ball joints, so that the radial blowingassisting nozzles 21 can realize spherical rotation relative to the power-assisting device 2, and the wind blown out from the radial blowing-assisting nozzles 21 is radial wind directed towards a tunnel wall. When a whirl suction flow field expanded by the whirl suction device 4 in a tunnel via the dust suction cylinder 41 is insufficient to drive away dust on the tunnel wall, it is necessary to start radial blowing-assisting wind to strengthen the effect of driving away dust on the tunnel wall. When a whirl suction flow field expanded by the whirl suction device 4 in a tunnel via the dust suction cylinder 41 is sufficient to drive away dust on the tunnel wall, the radial blowingassisting wind can be interrupted.

[0046] Multiple longitudinal suction-assisting nozzles 22 are arranged on a left end, facing the air curtain device 3, of the power-assisting device 2, and the radial blowing-assisting nozzles 21 and the longitudinal suction-assisting nozzles 22 form the air outlet of the power-assisting device 2.

[0047] The power-assisting device 2 can be of a hollow support plate structure. The angular positions of the radial blowing-assisting nozzles 21 can be adjusted by additional control systems and driving devices, so that blowing-assisting airflow produced by the radial blowing-assisting nozzles 21 can sweep a part of the tunnel wall or gaps with various shapes at various positions at an angle most beneficial for driving away the dust as much as possible.

[0048] The longitudinal suction-assisting nozzles 22 are located in the central area of the powerassisting device 2. During the non-rotation of the power-assisting device 2, the longitudinal suction-assisting nozzles 22 produce longitudinal suction-assisting wind flowing along the center line of the air outlet of the air blower 1. The radial blowing-assisting nozzles 21 and the longitudinal suction-assisting nozzles 22 can be opened or closed as required by additional control systems and driving devices. Opening or closing of the radial blowing-assisting nozzles and the longitudinal suction-assisting nozzles depends on the degree of dust covered on a tunnel surface and the degree of dust suspended in a tunnel space. Generally speaking, the thicker the dust covered on the tunnel surface or the higher the concentration of the dust suspended in the tunnel space detected by relevant sensors, the greater the intensity of the required blowing-assisting wind or suction-assisting wind. In case that it is difficult to drive away the dust covered on a local surface of the tunnel at a certain position, the power-assisting device can be kept at non-rotation, so that the airflow at the most favorable angle for driving away dust can continuously impact the surface for a period of time.

[0049] The power-assisting device 2 can be driven to rotate through the revolute pair 23 by additional control systems and driving devices so as to drive the radial blowing-assisting nozzles 21 and the longitudinal suction-assisting nozzles 22 to sweep corresponding circumferences, the absolute speed of the airflow produced by the radial blowing-assisting nozzles 21 is the combination of the following velocity of rotation of the power-assisting device 2 and the relative speed of an airflow jet, and the direction of the absolute speed of the jet can be changed at different times by adjusting the following velocity. Thus, airflow impact on the tunnel surface with local shapes at different positions can be realized, so that dust on the tunnel surface can be driven away.

[0050] As shown in FIG. 1, the air curtain device 3 is integrated and capable of moving as a whole with the whirl suction device 4, the dust removal device 5, and the extraction fan 7. Specifically, the air curtain device 3 is integrated with the whirl suction device 4, the dust removal device 5, and the extraction fan 7 and mounted on a mobile trolley, and the respective movements of this mobile trolley and the mobile trolley of the power-assisting device 2 can be controlled by additional control systems to adjust distance between the two mobile trolleys. Generally speaking, in case that the distance between the power-assisting device 2 and the whirl suction device 4 is greater than the length of effective whirl suction airflow formed in the tunnel, it is required to increase corresponding longitudinal suction-assisting airflow in order to push dust which is weakly affected by whirl suction airflow at a position far away from the front of the dust suction cylinder 41 into an effective whirl suction flow field. However, in case that the distance between the powerassisting device 2 and the whirl suction device 4 is less than or equal to the length of the effective whirl suction airflow in the tunnel, the longitudinal suction-assisting airflow should be interrupted to avoid from destroying the effective whirl suction flow field in the tunnel. The length of the effective whirl suction flow field in tunnel can be detected by addition anemometers and ranging sensors. When the whirl suction device 4 removes dust along a length direction of the tunnel in a shorter tunnel, or when the whirl suction device 4 removes dust towards the tunnel wall, there may be no space for placing the power-assisting device 2, and the power-assisting device 2 may be removed.

[0051] The whirl suction device 4, the dust removal device 5, and the extraction fan 7 are connected through an air pipeline in sequence, and an air inlet of the whirl suction device 4 is arranged towards the power-assisting device 2. The whirl suction device 4 and the power-assisting device 2 are both arranged horizontally so as to ensure that airflow blown out from only the longitudinal suction-assisting nozzles 22 is directed towards the dust suction cylinder 41 on the whirl suction device 4 during non-rotation of the power-assisting device 2.

[0052] As shown in FIG. 1, FIG. 3 and FIG. 4, an air inlet and an air outlet are formed in the air curtain device 3. The air curtain device 3 includes two cover plates 32, and the cover plates are spaced by several support columns 33. Tail ends of the cover plates 32 are bent towards the powerassisting device 2 to form an annular groove 31, and the diameter of a bent tail end of the annular groove 31 is gradually decreased. The annular groove 31 forms the air outlet of the air curtain device 3. The annular groove 31 is arranged opposite to the power-assisting device 2.

[0053] Through the two spaced cover plates 32, the annular groove 31 is formed in the air curtain device. The annular groove 31 is arranged opposite to the radial blowing-assisting nozzles 21.

[0054] The air outlet of the power-assisting device 2 is arranged opposite to the air outlet of the air curtain device 3.

[0055] As shown in FIG. 1, when the radial blowing-assisting nozzles 21 produces radial airflow to the tunnel wall, the annular groove 31 generates the radial airflow to the tunnel wall to form an air curtain, so that dusty airflow is prevented from entering the space where the dust removal device 5 is located.

[0056] The whirl suction device 4 is of a horizontal structure, and includes a dust suction cylinder 41 and a tornado generator 42. The dust suction cylinder 41 is in shape of a trumpet with its larger end facing the power-assisting device 2 in order to expand the whirl suction flow field formed by the tornado generator 42 in the whirl suction flow field generating cylinder 422 into the tunnel, so that the whirl suction flow field spirally advancing towards the dust suction cylinder 41 as a whole is formed in the tunnel.

[0057] As shown in FIG. 1 and FIG. 4, the extraction fan 7 is in communication with the return air pipeline 6, an air valve 61 and the air inlet of the air curtain device 3. A tangential air inlet 43 of the whirl suction device 4 is in communication with the extraction fan 7 through the return air pipeline 6.

[0058] A whirl suction device outlet 44 of the tornado generator 42 is in communication with the dust removal device 5.

[0059] The tornado generator 42 includes a total circulation channel 421, a whirl suction flow field generating cylinder 422, and multiple uniformly distributed tangential wind distribution channels 423. The whirl suction flow field generating cylinder 422 is arranged inside the total circulation channel 421. The total circulation channel 421 is in communication with the whirl suction flow field generating cylinder 422 through the multiple tangential wind distribution channels 423. The tangential wind distribution channels 423 are tangent to the whirl suction flow field generating cylinder 422 to provide tangential wind in rotational movement for the whirl suction flow field generating cylinder 422. The tangential air inlet 43 is in communication with the total circulation channel 421. An outlet of the whirl suction flow field generating cylinder 422 is provided as the whirl suction device outlet 44. Under combined action of the tangential wind provided by the tangential wind distribution channels 423 and axial negative pressure produced by the extraction fan 7, whirl suction airflow integrally spirally moving towards the extraction fan 7 as a whole is generated in the whirl suction flow field generating cylinder 422.

[0060] The airflow conveyed by the return air pipeline 6 enters the total circulation channel 421 from the tangential air inlet 43 and forms high-speed airflow. When the high-speed airflow enters the whirl suction flow field generating cylinder 422 via the tangential wind distribution channel 423, rotational wind is built in the whirl suction flow field generating cylinder 422, and then a whirl suction flow field with tornado characteristics is formed under combined action of negative pressure produced by the extraction fan 7.

[0061] Between the power-assisting device 2 and the air curtain device 3, the radial airflow blown out from the radial blowing-assisting nozzles 21 drives away the dust on the tunnel wall which is weakly affected by the whirl suction flow field. The airflow produced by the longitudinal suctionassisting nozzles 22 pushes the suspended dust which is weakly affected by the whirl suction flow field to the whirl suction flow field along the longitudinal direction, and then the dusty airflow is sucked into the dust removal device 5 from the dust suction cylinder 41 by the whirl suction device 4 by means of the whirl suction flow field expanded by the dust suction cylinder 41.

[0062] As shown in FIG. 1, an air valve 61 is arranged on the return air pipeline 6, and the air valve 61 is arranged near the air inlet of the air curtain device 3. By adjusting the opening size of the air valve 61, a stream of airflow in the return air pipeline 6 enters the whirl suction device 4 through the tangential air inlet 43 to form rotating airflow with sufficient strength, and another stream of airflow enters the air curtain device 3 through the air valve.

[0063] The present invention also provides a tunnel dust removal method, performed by using the tunnel dust removal system above, including the following steps.

[0064] The airflow conveyed by the air blower 1 is accept by the power-assisting device 2. assisting wind, namely, blowing-assisting wind and suction-assisting wind, is produced from the power-assisting device 2. The blowing-assisting wind is used for helping the whirl suction flow field in the tunnel to drive away the dust on the tunnel wall, and the suction-assisting wind is used for helping the whirl suction flow field in the tunnel to force the dust suspended in the tunnel into the dust suction cylinder.

[0065] The air curtain is provided by the air curtain device 3 to prevent the dust from diffusing into a tunnel area where the dust removal device 5 is located.

[0066] The whirl suction flow field spirally advancing towards the dust suction cylinder 41 as a whole in the tunnel is provided by the whirl suction device 4 via the dust suction cylinder 41, to drive away the adhered dust on the wall surface and make the suspended dust enter the dust suction cylinder 41.

[0067] Cleaned airflow treated by the dust removal device 5 enter the return air pipeline 6 by means of the extraction fan 7, and a part of the cleaned airflow flows back to the air curtain device 3 to form the air curtain while another part of the cleaned airflow is fed into the tangential air inlet 43 then the total circulation channel 421 to form the rotating airflow.

[0068] Flow volumes of the air blower 1 and the extraction fan 7, the rotational speed of the power-assisting device 2, positions of the radial blowing-assisting nozzles 21, flow rates of the radial blowing-assisting nozzles 21 and the longitudinal suction-assisting nozzles 22, distance between the power-assisting device 2 and the dust suction cylinder 41, and flow rate of the air curtain can be controlled, so that the dynamic dust removal of the tunnel space and the tunnel wall between the power-assisting device 2 and the whirl suction device 4 is realized ontime.

[0069] In case that it is difficult to smoothly suck the dust suspended in front of the dust suction cylinder 41 into the whirl suction device 4 by means of the whirl suction flow field expanding into the tunnel via the dust suction cylinder 41, the power-assisting device 2 is started to produce the suction-assisting wind with a corresponding flow rate to assist in forcing the suspended dust into the whirl suction device 4. In case that it is difficult to smoothly drive away the dust on the tunnel wall by means of the whirl suction flow field expanding into the tunnel via the dust suction cylinder 41, the power-assisting device 2 is started to produce the blowing-assisting wind with a corresponding flow rate to drive away the dust on the tunnel wall. By means of the suitable distance between the dust suction cylinder 41 and the power-assisting device 2, it is ensured that the whirl suction flow field expanding 41 into the tunnel via the dust suction cylinder is not weakened by the power-assisting wind produced by the power-assisting device 2.

[0070] Embodiment I: dust removal application of a construction tunnel

[0071] As shown in FIG. 6, this embodiment is applied in tunnel construction by drilling and blasting method with high dust concentration. The dust removal method using the system is carried out on the construction tunnel.

[0072] Firstly, the air blower 1 is located at a side of a tunnel with a tunnel face, and the extraction fan 7 is located at the other side of the tunnel with a tunnel entrance. The power-assisting device 2 and the air curtain device 3 are adjusted at a suitable distance by two mobile trolleys. The powerassisting device 2 can be rotated easily by means of the revolute pair 23 by providing corresponding driving devices. In order to ensure that dust on the wall surfaces at different positions and in different shapes falls off due to the action of airflow, the power-assisting device 2 often needs to rotate alternately in clockwise and counterclockwise directions at variable rotational speeds, or work when the power-assisting device 2 does not rotate as needed In order to ensure the efficiency of whirl suction dust removal, the rotational direction of the power-assisting device 2 is consistent with the movement direction of the rotating airflow produced by the whirl suction device 4. If the whirl suction flow field formed by the whirl suction device 4 is clockwise, the power-assisting device also rotates clockwise. Otherwise, the whirl suction flow field and the power-assisting device rotate counterclockwise together, which is more conducive to the formation of the whirl suction flow field.

[0073] After the radial blowing-assisting nozzles 21 are adjusted at suitable angles, the radial blowing-assisting nozzles 21 and the longitudinal suction-assisting nozzles 22 are opened.

[0074] Due to a high dust concentration in the air in the construction tunnel, it is necessary to open more longitudinal suction-assisting nozzles 22 on the power-assisting device 2.

[0075] When the tunnel dust removal system works, the high-speed airflow produced by the radial blowing-assisting nozzles 21 blows the dust attached to the wall surface to float in the air. The longitudinal suction-assisting nozzles 22 produce longitudinal airflow in velocity. On one hand, the longitudinal airflow can push the dusty air into the whirl suction device 4 quickly. On the other hand, the longitudinal suction-assisting airflow in the middle of the power-assisting device 2 is faster than peripheral airflow, according to the Bernoulli's effect, a low-pressure area is produced at the central axis (i.e. the rotation axis of the power-assisting device 2), so that the dusty airflow is further gathered toward the center.

[0076] The dusty airflow is sucked by the whirl suction device 4 and then enters the dust removal device 5. The cleaned airflow after dust removal is sent into the return air pipeline 6 by the extraction fan 7, a part of the cleaned airflow is sent into the whirl suction device 4 as rotating airflow while the rest of the cleaned airflow enters the air curtain device 3. The annular groove of the air curtain device 3 blows out radial wind to produce a tight air curtain to prevent the dust from spreading to the cleaned area.

[0077] The radial blowing-assisting nozzles 21 and the longitudinal suction-assisting nozzles 22 can work cooperatively or independently according to the requirements of working conditions. It is sometime unnecessary to open all the radial blowing-assisting nozzles 21 or all the longitudinal suction-assisting nozzles 22 at the same time, and the radial blowing-assisting nozzles 21 or the longitudinal suction-assisting nozzles 22 at specified positions may be set as required. According to the requirements of working conditions, the power-assisting device 2 and the whirl suction device 4 can also work cooperatively or independently, but the radial blowing-assisting wind or longitudinal suction-assisting wind provided by the power-assisting device 2 is neither allowed to destroy the effective whirl suction flow field in or in front of the dust suction cylinder 41, nor allowed to force the dust into the tunnel space where the dust removal device is located.

[0078] An air dust concentration detection device can be attached to the tunnel dust removal system. Once the detection device detects that the dust concentration near the left side of the air curtain device is reduced to a set value, a signal is sent to drive the dust removal system to move forward as a whole, and the driving speed cannot be higher than the effective dust removal space length in a unit time. In principle, the power-assisting device and air curtain device of the tunnel dust removal system can move independently left and right. However, it is necessary to ensure that the right end of the air curtain device is not polluted by the dusty airflow, and the air blower is located in a tunnel space where dust has not been removed.

[0079] Embodiment II: dust removal application of an operating tunnel

[0080] The metro operating tunnel belongs to the operating tunnel with relatively complex internal facilities, so the metro tunnel is taken as an example as follows. As shown in FIG. 7, lighting lamps 8, cables 9, distribution boxes 10 and other facilities are mounted on the wall surface of the metro tunnel.

[0081] Due to vehicle size limit in the metro operating tunnel, the dust removal facilities should not exceed the dimension limit stipulated by the railway regulations during working, so that the nozzles and the annular groove are far away from the tunnel wall surface, so the speed of ejecting radial blowing-assisting airflow and the air curtain will be relatively large. However, the airflow speed cannot be too large. On one hand, the effective whirl suction flow field in the tunnel is not allowed to be destroyed because of the radial blowing-assisting airflow with too high speed. On the other hand, a lampshade of a lighting lamp is not allowed to be crushed by sand and gravel carried in the airflow with too high speed.

[0082] The distribution boxes, the cables and other facilities on the tunnel wall surface block the corresponding tunnel wall surface, and open gaps with different directions are formed. Therefore, the positions of the radial blowing-assisting nozzles are controlled by providing corresponding control systems and driving devices, so that the included angles of the axes of all the radial blowing-assisting nozzles with respect to the radial lines of the assisting device are different in the same working time (as shown in FIG. 7), and the included angles of all the blowing-assisting nozzles with respect to the radial lines of the assisting device are changed in different time, so that the open gaps with different directions have the opportunity to be effectively injected by the airflow blown by the radial blowing-assisting nozzles under the same rotational direction condition of the assisting device. As shown in FIG. 7, when the assisting device is stationary, the airflow produced in the radial blowing-assisting nozzle a can enter a gap between the distribution box and the wall for cleaning; and the airflow produced in the radial blowing-assisting nozzle b can directly enter gaps between the cables for cleaning. At the same time, through the clockwise and counterclockwise back-and-forth rotation or static rotation of the power-assisting device, the opportunity of airflow injection in the open gaps with various directions is further increased, and the dust adhered on the surface is easy to fall off.

[0083] Therefore, the working process of the tunnel dust removal system in the operating tunnel is as follows.

[0084] Firstly, the dust removal system stays at the position where dust removal is needed in the tunnel by two mobile trolleys, and the power-assisting device keeps a suitable distance from the air curtain device. The power-assisting device 2 rotates correspondingly through the revolute pair, and the positions of the radial blowing-assisting nozzles are adjusted at the same time in order that the dust adhered to the surface can fall down. As the whirl suction dust removal efficiency is ensured, at the same time, the longitudinal suction-assisting nozzles are opened, and the whirl suction device is started. The direction of rotation of the power-assisting device 2 is consistent with the movement direction of the rotating airflow produced by the whirl suction device 4.

[0085] When the system is started, a suitable number of longitudinal suction-assisting nozzles 22 are opened according to the dust concentration in the air in the tunnel and the distance between the blowing-assisting device and the whirl suction device.

[0086] When the tunnel dust removal system works, the high-speed airflow produced by the radial blowing-assisting nozzles 21 blows the dust attached to the wall surface to float in the air. The longitudinal suction-assisting nozzles 22 produce longitudinal airflow in velocity. On one hand, the longitudinal airflow can push the dusty air into the whirl suction flow field quickly. On the other hand, the longitudinal suction-assisting airflow in the central area of the blowing-assisting device 2 is faster than peripheral airflow, according to the Bernoulli's effect, a low-pressure area is produced at the central axis (i.e. the rotation axis of the power-assisting device 2), so that the dusty airflow is further gathered toward the center.

[0087] The dusty airflow is sucked by the whirl suction device 4 and then enters the dust removal device 5. The cleaned airflow after dust removal is sent into the return air pipeline 6 by the extraction fan 7, a part of the cleaned airflow is sent into the whirl suction device 4 as rotating airflow while the rest of the cleaned airflow enters the air curtain device 3. The annular groove of the air curtain device 3 blows out radial wind to produce a tight air curtain to prevent the dust from spreading to the cleaned area.

[0088] The radial blowing-assisting nozzles 21 and the longitudinal suction-assisting nozzles 22 can work cooperatively or independently according to the requirements of working conditions. It is sometime unnecessary to open all the radial blowing-assisting nozzles 21 or all the longitudinal suction-assisting nozzles 22 at the same time, and the radial blowing-assisting nozzles 21 or the longitudinal suction-assisting nozzles 22 at specified positions may be set as required. According to the requirements of working conditions, the power-assisting device 2 and the whirl suction device 4 can also work cooperatively or independently, but the radial blowing-assisting wind or longitudinal suction-assisting wind provided by the power-assisting device 2 is neither allowed to destroy the effective whirl suction flow field in or in front of the dust suction cylinder 41, nor allowed to force the dust into the tunnel space where the dust removal device is located.

[0089] An air dust concentration detection device can be attached to the tunnel dust removal system. Once the detection device detects that the dust concentration near the left side of the air curtain device is reduced to a set value, a signal is sent to drive the dust removal system to move forward as a whole. In principle, the power-assisting device and air curtain device of the tunnel dust removal system can move independently left and right. However, it is necessary to ensure that the right end of the air curtain device is not polluted by the dusty airflow, and the air blower is located in a tunnel space where dust has not been removed.

[0090] The above are only the embodiments of the present invention and not intended to limit the patent scope of the present invention, and any equivalent structures or equivalent process transformations based on the specification and the attached figures of the present invention, which is directly or indirectly applied in other related technical fields, shall similarly fall within the scope of patent protection of the present invention.

[0091] Alternative expressions of the inventive concept are set out in the following numbered clauses: 1. A tunnel dust removal system, wherein the tunnel dust removal system comprises an air blower (1), a whirl suction device (4), a dust removal device (5), an extraction fan (7), a powerassisting device (2) with an air outlet and an air inlet, and an air curtain device (3) with an air outlet and an air inlet, an outlet of the air blower (1) is in communication with the air inlet of the power assisting device (2), and the air outlet of the power-assisting device (2) is arranged opposite to the air outlet of the air curtain device (3); the air blower (1) is integrated and capable of moving as a whole with the power-assisting device (2), and the air curtain device (3) is integrated and capable of moving as a whole with the whirl suction device (4), the dust removal device (5), and the extraction fan (7); the whirl suction device (4), the dust removal device (5) and the extraction fan (7) are connected through an air pipeline in sequence, and an air inlet of the whirl suction device (4) is arranged towards the air outlet of the power-assisting device (2); the air inlet of the air curtain device (3) is in communication with a return air pipeline (6) and the extraction fan (7) through an air valve (61), and a tangential air inlet (43) of the whirl suction device (4) is in communication with the extraction fan (7) through the return air pipeline (6). 2. The tunnel dust removal system according to clause 1, wherein blowing-assisting wind produced by a plurality of radial blowing-assisting nozzles (21) connected to a periphery of the power-assisting device (2) through ball joints acts on a tunnel wall so as to help a whirl suction flow field provided by the whirl suction device (4) to drive away dust on the tunnel wall, suctionassisting wind towards a dust suction cylinder (41) produced by a plurality of longitudinal suctionassisting nozzles (22) on the power-assisting device (2) appears to help the whirl suction flow field formed by the whirl suction device (4) to take away dust suspended in front of the whirl suction device (4), and all the radial blowing-assisting nozzles (21) and all the longitudinal suctionassisting nozzles (22) are provided with switches. 3. The tunnel dust removal system according to clause 1 or 2, wherein the power-assisting device (2) is mounted on the air blower (1) by means of a revolute pair (23), and during operation of the longitudinal suction-assisting nozzles (22), rotation directional of the power-assisting device (2) is consistent with rotation directional of rotating airflow produced by the whirl suction device (4); the whirl suction device (4) and the power-assisting device (2) are both arranged horizontally so as to ensure that airflow blown out from only the longitudinal suction-assisting nozzles (22) is directed towards the dust suction cylinder (41) on the whirl suction device (4) during non-rotation of the power-assisting device (2). 4. The tunnel dust removal system according to clause 1 or 2, wherein the whirl suction device (4) comprises a dust suction cylinder (41) and a tornado generator (42), the tangential air inlet (43) and a whirl suction device outlet (44) are designed in the tornado generator (42), the return air pipeline (6) is in communication with the tangential air inlet (43), and the whirl suction device outlet (44) of the tornado generator (42) is in communication with the dust removal device (5). 5. The tunnel dust removal system according to clause 4, wherein the tornado generator (42) comprises a total circulation channel (421), a whirl suction flow field generating cylinder (422), and a plurality of uniformly distributed tangential wind distribution channels (423), the whirl suction flow field generating cylinder (422) is arranged inside the total circulation channel (421), the total circulation channel (421) is in communication with the whirl suction flow field generating cylinder (422) through the tangential wind distribution channels (423), and the tangential wind distribution channels (423) provide tangential wind in rotational movement for the whirl suction flow field generating cylinder (422); the tangential air inlet (43) is in communication with the total circulation channel (421), and an outlet of the whirl suction flow field generating cylinder (422) is provided as the whirl suction device outlet (44), and under combined action of the tangential wind provided by the tangential wind distribution channels (423) and axial negative pressure produced by the extraction fan (7), whirl suction airflow spirally moving towards the extraction fan (7) as a whole is generated in the whirl suction flow field generating cylinder (422). 6. The tunnel dust removal system according to clause 4, wherein the dust suction cylinder (41) is in shape of a trumpet with its larger end facing the power-assisting device (2) in order to expand a whirl suction flow field formed in a whirl suction flow field generating cylinder (422) into a tunnel, so that the whirl suction flow field spirally advancing towards the dust suction cylinder (41) as a whole is built in the tunnel, and a suitable distance between the dust suction cylinder (41) and the power-assisting device (2) is set. 7. The tunnel dust removal system according to clause 4, wherein an air valve (61) is arranged on the return air pipeline (6), and the air valve (61) is arranged adjacent to the air inlet of the air curtain device (3). 8. The tunnel dust removal system according to clause 1 or 2, wherein the air curtain device (3) comprises two cover plates (32) and several support columns (33) spacing the two cover plates (32); peripheries of the two cover plates (32) are bent towards the power-assisting device (2) to form an annular groove (31), and the annular groove (31) is formed as the air outlet of the air curtain device (3); and the annular groove (31) is arranged opposite to the power-assisting device (2). 9. The tunnel dust removal system according to clause 1 or 2, wherein angles between axes of radial air outlets of the radial blowing-assisting nozzles (21) on the power-assisting device (2) and corresponding radial lines on the power-assisting device during operation are different from each other. 10. A tunnel dust removal method using the tunnel dust removal system according to any one of clauses 1 to 9, wherein the tunnel dust removal method comprises: making the power-assisting device (2) accept airflow conveyed by the air blower (1); producing power-assisting wind, i.e., blowing-assisting wind and suction-assisting wind, from the power-assisting device (2); the blowing-assisting wind is used for helping whirl suction flow field in a tunnel to drive away dust on a tunnel wall while the suction-assisting wind is used for helping the whirl suction flow field in the tunnel to force dust suspended in the tunnel into a dust suction cylinder; producing an air curtain by the air curtain device (3) to prevent the dust from diffusing into a tunnel area where the dust removal device (5) is located; making the whirl suction device (4) produce the whirl suction flow field spirally advancing towards the dust suction cylinder (41) as a whole in the tunnel via the dust suction cylinder (41) to drive away dust adhered on a wall surface and make suspended dust enter the dust suction cylinder (41); making cleaned airflow treated by the dust removal device (5) enter the return air pipeline (6) by means of the extraction fan (7), and making a part of the cleaned airflow flow back to the air curtain device (3) to form the air curtain; feeding another part of the cleaned airflow into the tangential air inlet (43) then a total circulation channel (421) to form a rotating airflow; flow volumes of the air blower (1) and the extraction fan (7), rotational speed and rotational direction of the power-assisting device (2), positions of radial blowing-assisting nozzles (21), flow rates of the radial blowing-assisting nozzles (21) and longitudinal suction-assisting nozzles (22), distance between the power-assisting device (2) and the dust suction cylinder (41) and flow rate of the air curtain are all capable of being controlled, so that synergistic dust removal of a tunnel space and the tunnel wall between the power-assisting device (2) and the whirl suction device (4) is realized; starting the power-assisting device (2) to produce the suction-assisting wind with a corresponding flow rate to assist in forcing suspended dust into the whirl suction device (4) in case that it is difficult to smoothly suck the suspended dust in front of the dust suction cylinder (41) into the whirl suction device (4) by means of the whirl suction flow field expanding into the tunnel via the dust suction cylinder (41); and starting the power-assisting device (2) to produce the blowing-assisting wind with a corresponding flow rate to drive away dust on the tunnel wall in case that it is difficult to smoothly drive away the dust on the tunnel wall by means of the whirl suction flow field expanding into the tunnel via the dust suction cylinder (41).

Claims

02 09 241. A tunnel dust removal method using a tunnel dust removal system, wherein the tunnel dust removal system comprises an air blower (1), a whirl suction device (4), a dust removal device (5), an extraction fan (7), a power-assisting device (2) with an air outlet and an air inlet, and an air curtain device (3) with an air outlet and an air inlet, an outlet of the air blower (1) is in communication with the air inlet of the power-assisting device (2), and the air outlet of the powerassisting device (2) is arranged opposite to the air outlet of the air curtain device (3); the air blower (1) is integrated and capable of moving as a whole with the power-assisting device (2), and the air curtain device (3) is integrated and capable of moving as a whole with the whirl suction device (4), the dust removal device (5), and the extraction fan (7); the whirl suction device (4), the dust removal device (5) and the extraction fan (7) are connected through an air pipeline in sequence, and an air inlet of the whirl suction device (4) is arranged towards the air outlet of the powerassisting device (2); the air inlet of the air curtain device (3) is in communication with a return air pipeline (6) and the extraction fan (7) through an air valve (61), and a tangential air inlet (43) of the whirl suction device (4) is in communication with the extraction fan (7) through the return air pipeline (6);the whirl suction device (4) comprises a dust suction cylinder (41) and a tornado generator (42), the tangential air inlet (43) and a whirl suction device outlet (44) are designed in the tornado generator (42), the return air pipeline (6) is in communication with the tangential air inlet (43), and the whirl suction device outlet (44) of the tornado generator (42) is in communication with the dust removal device (5);the tornado generator (42) comprises a circulation channel (421), a whirl suction flow field generating cylinder (422), and a plurality of uniformly distributed tangential wind distribution channels (423), the whirl suction flow field generating cylinder (422) is arranged inside the circulation channel (421), the circulation channel (421) is in communication with the whirl suction flow field generating cylinder (422) through the tangential wind distribution channels (423), and the tangential wind distribution channels (423) provide tangential wind in rotational movement for the whirl suction flow field generating cylinder (422); the tangential air inlet (43) is in communication with the circulation channel (421), and an outlet of the whirl suction flow field generating cylinder (422) is provided as the whirl suction device outlet (44), and under combined action of the tangential wind provided by the tangential wind distribution channels (423) and axial negative pressure produced by the extraction fan (7), whirl suction airflow spirally moving towards the extraction fan (7) as a whole is generated in the whirl suction flow field generating cylinder02 09 24(422);wherein the tunnel dust removal method comprises the following steps:producing an air curtain from the air curtain device (3) to prevent dust from diffusing into a tunnel area where the dust removal device (5) is located;making the whirl suction device (4) produce, via the dust suction cylinder (41), the whirl suction flow field spirally advancing towards the dust suction cylinder (41) as a whole in a tunnel to drive away dust adhered on a wall surface and make suspended dust enter the dust suction cylinder (41);making the power-assisting device (2) accept airflow conveyed by the air blower (1);starting the power-assisting device (2) to produce suction-assisting wind with a corresponding flow rate to assist in forcing the suspended dust into the dust suction cylinder (41) of the whirl suction device (4) in case that it is difficult to smoothly suck the suspended dust in front of the dust suction cylinder (41) into the whirl suction device (4) by means of the whirl suction flow field expanding into the tunnel via the dust suction cylinder (41);starting the power-assisting device (2) to produce blowing-assisting wind with a corresponding flow rate to drive away dust on a tunnel wall in case that it is difficult to smoothly drive away the dust on the tunnel wall by means of the whirl suction flow field expanding into the tunnel via the dust suction cylinder (41);making cleaned airflow treated by the dust removal device (5) enter the return air pipeline (6) by means of the extraction fan (7), and making a part of the cleaned airflow flow back to the air curtain device (3) to form the air curtain; feeding another part of the cleaned airflow into the tangential air inlet (43) then the circulation channel (421) to form a rotating airflow;controlling flow volumes of the air blower (1) and the extraction fan (7), rotational speed and rotational direction of the power-assisting device (2), positions of radial blowing-assisting nozzles (21), flow rates of the radial blowing-assisting nozzles (21) and longitudinal suction-assisting nozzles (22), distance between the power-assisting device (2) and the dust suction cylinder (41) and flow rate of the air curtain to realize synergistic dust removal of a tunnel space and the tunnel wall between the power-assisting device (2) and the whirl suction device (4).

2. The tunnel dust removal method according to claim 1, wherein blowing-assisting wind produced by a plurality of radial blowing-assisting nozzles (21) connected to a periphery of the power-assisting device (2) through ball joints acts on the tunnel wall so as to help a whirl suction flow field provided by the whirl suction device (4) to drive away the dust on the tunnel wall, the suction-assisting wind towards a dust suction cylinder (41) produced by a plurality of longitudinal suction-assisting nozzles (22) on the power-assisting device (2) appears to help the whirl suction02 09 24flow field formed by the whirl suction device (4) to take away dust suspended in front of the whirl suction device (4), and all the radial blowing-assisting nozzles (21) and all the longitudinal suctionassisting nozzles (22) are provided with switches.

3. The tunnel dust removal method according to claim 1, wherein the dust suction cylinder (41) is in shape of a trumpet with its larger end facing the power-assisting device (2) in order to expand a whirl suction flow field formed in a whirl suction flow field generating cylinder (422) into the tunnel, so that the whirl suction flow field spirally advancing towards the dust suction cylinder (41) as a whole is built in the tunnel, and a suitable distance between the dust suction cylinder (41) and the power-assisting device (2) is set.

4. The tunnel dust removal method according to claim 1, wherein an air valve (61) is arranged on the return air pipeline (6), and the air valve (61) is arranged adjacent to the air inlet of the air curtain device (3).

5. The tunnel dust removal method according to claim 1, wherein the air curtain device (3) comprises two cover plates (32) and several support columns (33) spacing the two cover plates (32); peripheries of the two cover plates (32) are bent towards the power-assisting device (2) to form an annular groove (31), and the annular groove (31) is formed as the air outlet of the air curtain device (3); and the annular groove (31) is arranged opposite to the power-assisting device (2).

6. The tunnel dust removal method according to claim 1, wherein angles between axes of radial air outlets of the radial blowing-assisting nozzles (21) on the power-assisting device (2) and corresponding radial lines on the power-assisting device during operation are different from each other.

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