Inner and outer cyclone reverse flow air dust removal method and device

Abstract

The invention discloses an internal and external cyclone reverse diversion type air dust removal method and device, which relates to the field of air dust removal technology and solves the technical shortcomings of the existing cyclone centrifugal dust removal device, such as the complex structure and large volume. The technical solution includes: the shell is divided into an air inlet dust collection section, a cyclone reverse diversion section and an exhaust section. The air inlet dust collection section includes an air inlet tube and a dust collection box. The cyclone reverse diversion section includes a sealing ring, a guide vane, a fixing plate, a drive shaft and a centrifugal impeller. The beneficial effect of the present invention is that the centrifugal impeller drives the dust-laden air to move to form a rotating and rising internal cyclone. The particulate impurities therein radially settle under the action of centrifugal force and gravity to form an external airflow. The clean air rises to the upper end of the centrifugal impeller and enters the exhaust section through the radial air inlet channel and the radial air outlet channel. A small amount of clean air is diverted and returned under the action of the guide vane and drives the external airflow to rotate and descend to form an external cyclone. Most of the clean air settles in the dust collection box, and a small part converges into the internal cyclone. The dust removal effect is good and the structure is simple and the volume is small.

Description

Technical Field

[0001] The present invention relates to the technical field of air purification, and more particularly to an inner and outer cyclone reverse flow air dust removal method and a dust removal device using the method. Background Art

[0002] Air dust removal refers to the use of centrifugal separation, gravity separation, filtration separation, electrostatic adsorption separation or washing separation methods, with the help of dust removal devices corresponding to the dust removal method to separate inhalable particulate impurities from dust-laden air, thereby producing purified air. It has a wide range of applications and is widely used in ventilation and air-conditioning systems, air purification systems, industrial dust removal systems, oil fume purification systems, welding fume purification systems, paint mist purification systems in painting workshops and other fields, and has extremely high environmental, economic and social value.

[0003] The centrifugal separation dust removal method is the most widely used, relatively low-cost, and effective type of air dust removal method, and is mainly used in cyclone centrifugal dust removal devices. For example, a cyclone centrifugal dust removal device disclosed in Chinese Patent Publication No. CN201618621U mainly consists of an air inlet pipe, a guide plate, an air storage box, a bracket, an impeller, a motor, a conical cylinder, a volute, an exhaust pipe, a cyclone dust collector, a circulating air duct, and a regulating valve. The motor drives the impeller to push the dust-laden air in the conical cylinder into the cyclone dust collector through the volute. After the dust-laden air enters the cyclone dust collector, it will form a rotating downward external vortex. The dust suspended in the external vortex moves toward the wall of the device under the action of centrifugal force, and moves to the lower part of the dust collector with the external vortex, and is discharged from the dust discharge hole in the lower axial part. The purified gas forms an upward internal vortex in the cyclone dust collector and is discharged through the exhaust pipe in the middle axial part. Due to the structural design of the cyclone dust collector itself, this type of dust removal device can basically only separate non-sticky, non-fibrous dry dust with a particle size of 0.5 microns or more. It is not ideal for purifying dust-laden air with a particle size of less than 0.5 microns, and its scope of use is severely limited. Moreover, the overall structure of this type of dust removal device is relatively complex. The cyclone dust collector is usually designed to be taller and larger, and an additional circulating air duct is required to be connected to the cyclone dust collector to reflux and purify the purified air with low dust content separated from the cyclone dust collector. This results in a large overall size and floor space for the device, high space requirements for the site of use, high energy consumption and high noise during actual operation, and high manufacturing and use costs.

[0004] Therefore, it is necessary to provide an air dust removal method with better dust removal effect and capable of processing dust-containing air with different particle sizes, and to provide an air dust removal device based on this method. Summary of the Invention

[0005] To sum up, the purpose of the present invention is to solve the above-mentioned technical deficiencies and to provide a dust removal method with better dust removal effect and suitable for processing dust-laden air with different particle sizes, as well as an air dust removal device using this method with simple structure, small size, low cost, good dust removal effect and wide application range.

[0006] In order to solve the technical deficiencies proposed by the present invention, the technical solutions adopted are:

[0007] An inner and outer cyclone reverse flow air dust removal device includes a shell, characterized in that: the shell is divided into an air inlet dust collection section, a cyclone reverse flow section and an exhaust section that are interconnected, the air inlet dust collection section includes an air inlet tube arranged at the bottom of the shell and a dust collection box arranged outside the air inlet tube, and the upper end cover of the dust collection box is provided with a dust collection port. The cyclone reverse flow section includes a sealing ring radially fixed to the upper part of the shell side wall and coaxial with the air inlet tube, a fixing plate radially fixed above the sealing ring, the diameter of which is larger than the aperture of the inner circular hole and smaller than the inner diameter of the shell, and a plurality of guide plates tightly axially arranged between the fixing plate and the sealing ring, a lateral air inlet channel is formed between adjacent guide plates at one end of the inner circular hole of the sealing ring, and a lateral air outlet channel is formed at one end of the edge of the fixing plate. A drive shaft is mounted on the fixed plate, connected to a centrifugal impeller axially positioned within the cyclone reverse diversion section. The upper end of the centrifugal impeller passes through the inner circular hole of the isolation ring and is positioned within the inner side of the lateral air inlet channel, while the lower end is positioned within the upper portion of the air inlet cylinder. The guide vane is an inwardly inclined, forward-leaning structure, with one end of the lateral air inlet channel tilted forward in the same direction as the centrifugal impeller's rotation, thereby diverting airflow at the lateral air inlet channel opening. The exhaust section includes an exhaust port, which communicates with the cyclone reverse diversion section via the lateral air outlet channel.

[0008] Preferably, the centrifugal impeller is a multi-blade forward-inclined impeller.

[0009] Preferably, the ratio of the axial height to the radial width of the centrifugal impeller is between 0.5 and 3, the ratio of the axial height of the guide vane to the axial height of the centrifugal impeller is between 0.1 and 0.25, and the ratio of the inner diameter of the circle surrounded by the guide vane to the radial width of the centrifugal impeller is between 1.1 and 1.5.

[0010] Specifically, an air inlet is provided in the middle position of the bottom surface of the shell, the air inlet tube is axially connected to the air inlet, the upper end cover is radially fixedly sleeved on the upper part of the outer wall of the air inlet tube, and a gap is left between the outer peripheral edge of the upper end cover and the side wall of the shell to form the dust collecting port, the bottom surface, side wall, outer wall of the air inlet tube, and upper end cover of the shell together constitute the dust collecting box.

[0011] Specifically, the diameter of the inner circular hole of the isolation ring is not less than the diameter of the air inlet tube.

[0012] Specifically, the centrifugal impeller includes a top connecting plate fixedly connected to the drive shaft, a bottom fixing piece parallel to and opposite to the top connecting plate and having a dust-laden air inlet in the middle, and a plurality of forward-inclined blades evenly distributed between the top connecting plate and the bottom fixing piece. The forward-inclined blades are axially distributed in a clockwise or counterclockwise direction around the periphery of the dust-laden air inlet to form an axial air inlet channel in the middle of the centrifugal impeller.

[0013] Furthermore, the ratio of the diameter of the axial air inlet channel to the radial width of the centrifugal impeller is between 0.2 and 0.8.

[0014] Specifically, the present invention provides an inner and outer cyclone reverse flow air dust removal method, which is characterized by comprising the following steps:

[0015] The first step is to inhale dust-laden air: the drive shaft, driven by an external power source, drives the centrifugal impeller to rotate along the forward inclination direction of the guide vane to reduce the air pressure in the cyclone reverse diversion section, thereby inhaling the dust-laden air outside the bottom of the shell into the axial air inlet channel of the centrifugal impeller through the air inlet tube.

[0016] The second step is the generation of internal and external cyclones: the dust-laden air entering through the axial air inlet channel is driven by the centrifugal impeller to rotate and rise at high speed along the air duct between the forward-inclined blades, forming an internal cyclone with a rotation direction in the same direction as the centrifugal impeller and an axial direction in the same direction as the air inlet. The airflow that rotates and rises to the upper end of the centrifugal impeller enters between the guide vanes through the lateral air inlet channel under the action of centrifugal force. The airflow is split into two parts by the action of the guide vanes, one part of which follows the guide vanes through the lateral air outlet channel into the exhaust section and is discharged outward through the exhaust port. The other part is blocked by the side of the guide vane at the lateral air inlet channel and split downward back into the cyclone reverse diversion section, driving the external airflow of the centrifugal impeller to rotate and descend, thereby forming an external cyclone on the outside of the centrifugal impeller with a rotation direction in the same direction as the centrifugal impeller and an axial direction opposite to the air inlet direction, forming an internal and external cyclone reverse diversion effect.

[0017] The third step is the separation of the gas-solid phase of the dust-laden air: substances with different masses and densities in the inner cyclone are subjected to different centrifugal accelerations of the centrifugal impeller during the rotating upward process. The greater the mass and density of the substance, the greater the centrifugal acceleration it receives, and the faster the radial sedimentation speed in the air duct of the centrifugal impeller. Compared with the substances with smaller mass and density, the substances can first move to the periphery of the centrifugal impeller to form an external airflow and settle into the dust collecting box through the dust collecting port along the side wall of the shell under the reverse push of the outer cyclone and the action of gravity. Similarly, clean air with small mass and density cannot radially separate from the centrifugal impeller to form external airflow at the same time due to the small centrifugal acceleration it is subjected to. Instead, it continues to rotate axially with the inner cyclone and rises to the upper end of the centrifugal impeller and enters the lateral air inlet channel under the action of centrifugal force. The clean air is split into two parts at the lateral air inlet channel mouth of the guide vane. Most of the clean air is discharged to the outside of the shell through the lateral air outlet channel and the exhaust port, and the other part returns to the cyclone reverse diversion section and drives the external airflow with a large amount of dust that has radially settled outside the centrifugal impeller to rotate and descend to form an outer cyclone and finally settle axially in the dust collecting box.

[0018] The fourth step is that part of the outer cyclone flows into the inner cyclone: most of the outer cyclone settles into the dust collecting box through the dust collecting port under the action of the side wall of the shell and gravity, and a small part of the outer cyclone flows into the inner cyclone near the upper end of the air inlet tube and the bottom end of the centrifugal impeller to realize circulating dust removal.

[0019] Furthermore, the method also includes a method for adjusting the specifications and dimensions of various components of the dust removal device when purifying dust-laden air containing particles of different sizes, including:

[0020] A. When separating dusty air containing impurity particles with a diameter of 5 microns or more, the ratio of the diameter of the axial air inlet channel of the centrifugal impeller to the radial width of the centrifugal impeller is between 0.2 and 0.5, and the ratio of the axial height of the centrifugal impeller to the radial width of the centrifugal impeller is between 0.5 and 1;

[0021] B. When separating dusty air containing impurity particles with a diameter of less than 5 microns, the ratio of the diameter of the axial air inlet channel of the centrifugal impeller to the radial width of the centrifugal impeller is between 0.5 and 0.8, and the ratio of the axial height of the centrifugal impeller to the radial width of the centrifugal impeller is between 1 and 3.

[0022] The beneficial effects of the present invention are:

[0023] The present invention is mainly used for dust removal and purification of dust-laden air. Based on the cyclone reverse dust removal principle, the reverse diversion effect of the inner and outer cyclones is utilized to separate inhalable particulate impurities from the dust-laden air.

[0024] The device of the present invention divides the housing into three interconnected sections, resulting in a simple overall structure. Driven by the centrifugal impeller, the dust-laden gas enters the axial air inlet channel of the centrifugal impeller through the upper opening of the air inlet cylinder and undergoes a high-speed upward rotation, forming an inner vortex. In the inner vortex, the larger particles, heavier mass, and denser inhalable particulate impurities undergo radial sedimentation during this upward rotation under the combined effects of centrifugal force and gravity. This causes the dust-laden airflow to reach a point where its axial velocity is zero before axially ascending to the upper end of the centrifugal impeller (i.e., the inner side of the lateral air inlet channel), preventing the inhalable particulate impurities from continuing to ascend axially with the inner vortex. Simultaneously, as the inhalable particulate impurities ascend axially to a point where their axial velocity is zero, they are radially moved to the outside of the centrifugal impeller under the action of centrifugal force, completing radial sedimentation and forming an external airflow. The purified air with a smaller dust content is subjected to a relatively smaller centrifugal acceleration. At the same time, its radial movement distance is smaller than that of the airflow with a larger dust content. When the inhalable particles complete radial sedimentation, the purified air is still in the air duct of the centrifugal impeller and has a certain axial speed, so that the purified air can continue to rise to the upper end of the impeller with the inner cyclone and enter between the guide vanes through the lateral air inlet channel.

[0025] Most of the purified air flows along the gaps between the guide vanes through the lateral air outlet channel into the exhaust section and is discharged through the exhaust port. A small amount of purified air or airflow containing trace amounts of small particulate impurities will be blocked by the side of the guide vane's lateral air inlet channel and diverted back to the cyclone reverse diversion section, driving the external airflow that has completed radial sedimentation and has a large dust content to rotate downward to form an outer cyclone. The formed outer cyclone rotates downward along the side wall of the shell. Most of the particulate impurities are driven by the outer cyclone through the dust collection port and settled into the dust collection box under the restriction of the shell side wall and the action of gravity. The remaining trace or small amount of particulate impurities are combined with a small part of the outer cyclone airflow between the upper end of the air inlet tube and the bottom end of the centrifugal impeller to the inner cyclone for circulation and purification.

[0026] Compared to existing cyclone centrifugal dust removal devices, this invention utilizes the principle of cyclone reverse flow separation. During the upward rotation of the inner cyclone, the radial sedimentation of inhalable particulate impurities is completed to form an external airflow. Simultaneously, the axial reverse motion characteristics of the outer cyclone drive the external airflow downward to form an outer cyclone, which forms a cyclone reverse flow separation dust removal effect with the inner cyclone. A portion of the dust-laden airflow in the outer cyclone is fed into the inner cyclone for circulation and purification, ultimately allowing the inhalable particulate impurities in the dust-laden air to fully settle into the dust collection box, achieving better dust removal results.

[0027] Moreover, compared with the existing cyclone centrifugal dust removal device, the present invention uses the shell, centrifugal impeller and guide vane to perform internal and external cyclone reverse diversion on the dust-laden air to separate the inhalable particulate impurities in the dust-laden air. There is no need to design the volute structure, cyclone dust collector structure and circulating air duct structure. The overall structural design is more concise and simple, which greatly reduces the production and manufacturing costs and is conducive to market promotion.

[0028] At the same time, the cyclone dust collector in the existing cyclone centrifugal dust removal device can only effectively process dust-containing air with a particle size of more than 5 microns. The method of the present invention can appropriately adjust and design the specifications and dimensions of the centrifugal impeller and the guide vane so that the device of the present invention can be used to purify dust-containing air containing inhalable particulate impurities of different particle sizes, so that the dust-containing air that can be processed by the device of the present invention is larger, the application range is wider, and the applicability is stronger.

[0029] In addition, the device of the present invention is compact and does not occupy space, has little space restriction on the site of use, and can be installed and used in an area with relatively small space. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a diagram of the overall structure of the device of the present invention, in which some structures are shown in perspective;

[0031] Figure 2 This is a schematic axial cross-sectional view of the connection structure of the housing, the baffle plate, the guide vane and the fixing plate of the device of the present invention;

[0032] Figure 3 This is a schematic diagram of the overall structure of the centrifugal impeller of the device of the present invention;

[0033] Figure 4 This is a schematic diagram of the overall axial cross-sectional structure of the device of the present invention;

[0034] Figure 5 A top view of the device of the present invention, wherein some structures are shown in perspective;

[0035] Figure 6 Schematic diagram of the reverse diversion effect of the guide vane of the device of the present invention;

[0036] Figure 7 is an aerodynamic curve diagram of the airflow inside the device of the present invention;

[0037] Figure 8 Schematic diagram of the specifications and dimensions of the various parts of the device of the present invention.

[0038] In the figure: 1. Shell, 11. Air inlet and dust collection section, 12. Cyclone reverse diversion section, 13. Exhaust section, 14. Air inlet, 15. Upper end cover, 16. Dust collection port, 17. Exhaust port, 2. Air inlet tube, 3. Dust collection box, 4. Sealing ring, 5. Fixing plate, 6. Guide vane, 61. Lateral air inlet channel, 62. Lateral air outlet channel, 7. Drive motor, 8. Centrifugal impeller, 81. Top connecting plate, 82. Dust-laden air inlet, 83. Bottom fixing part, 84. Forward-inclined blades, 85. Axial air inlet channel. DETAILED DESCRIPTION

[0039] The present invention will be further described below with reference to the accompanying drawings and preferred specific embodiments of the present invention.

[0040] Reference Figures 1 to 2 As shown in, the present invention:

[0041] An internal and external cyclone reverse diversion type air dust removal device includes a shell 1 with an overall cylindrical structure. The cylindrical shell 1 can be divided into an air inlet dust collection section 11 located at the lower part of the shell 1, a cyclone reverse diversion section 12 located in the middle part of the shell 1, and an exhaust section 13 located at the upper part of the shell 1, which are interconnected and can be divided from bottom to top along its axial direction.

[0042] Specifically, the air inlet and dust collecting section 11 includes an air inlet cylinder 2 axially arranged at the middle of the bottom surface of the shell 1 and a dust collecting box 3 arranged outside the air inlet cylinder 2 .

[0043] Specifically, a circular air inlet 14 is provided at the center of the circular bottom surface of the shell 1, extending vertically through the bottom surface. The air inlet tube 2 is axially connected to the air inlet 14. The air inlet tube 2 is a cylindrical structure extending vertically through the bottom surface of the shell 1. The bottom opening of the air inlet tube 2 located on the circular bottom surface of the shell 1 is the air inlet 14. The radial cross-sectional diameter of the air inlet tube 2 (i.e., the diameter of the air inlet 14) is smaller than the radial cross-sectional diameter of the shell 1. An upper end cover 15 of an annular structure is radially connected to the upper portion of the outer wall of the air inlet tube 2. The inner circular hole of the upper end cover 15 is integrally connected to the outer wall of the air inlet tube 2. A certain gap is left between the edge of the upper end cover 15 and the side wall of the shell 1 to form an annular dust collection port 16. The bottom surface, side wall of the shell 1, the outer wall of the air inlet tube 2, and the upper end cover 15 together constitute a dust collection box 3 surrounding the outside of the air inlet tube 2.

[0044] Specifically, the cyclone reverse diversion section 12 includes a side wall of the shell 1, a sealing ring 4 radially fixed to the upper part of the side wall of the shell 1 and coaxial with the air inlet tube 2, a fixing plate 5 radially fixed above the sealing ring 4, with a diameter larger than the aperture of the inner circular hole of the sealing ring 4 and smaller than the inner diameter of the shell 1, and a plurality of guide plates 6 tightly axially arranged between the end faces corresponding to the edge of the fixing plate 5 and the edge of the inner circular hole of the sealing ring 4.

[0045] Specifically, the upper and lower ends of the guide plate 6 are respectively fixedly connected to the corresponding end faces between the lower surface of the fixed plate 5 and the upper surface of the isolation ring 4. The adjacent guide plate 6 forms a lateral air inlet channel 61 on the side close to the inner circular hole of the isolation ring 4, and forms a lateral air outlet channel 62 on the side close to the edge of the fixed plate 5. The fixed plate 5 is fixedly connected to the side wall of the shell 1 through the guide plate 6 and the isolation ring 4.

[0046] Specifically, refer to Figure 2 、 Figure 5 and Figure 6 As shown, the guide vane 6 is an inwardly inclined forward structure, and the forward inclination direction of one end of the lateral air inlet channel is the same as the rotation direction of the centrifugal impeller to divert the airflow at the lateral air inlet channel opening.

[0047] It should be noted that the reason why the guide vane 6 of the device of the present invention can play the role of air flow diversion is mainly because one end of the lateral air inlet channel 61 of the guide vane 6 adopts an inward-leaning forward structural design, and its forward-leaning direction is the same as the rotation direction of the centrifugal impeller 8. The structural design of one end of the lateral air outlet channel 62 of the guide vane 6 is mainly to facilitate air outlet, and a forward-leaning deflection design is not required.

[0048] like Figure 5 and Figure 6 As shown, in actual use, the purified air that has moved axially to the upper end of the centrifugal impeller, under the action of centrifugal force, enters between the guide vanes 6 through the lateral air inlet channel. A certain angle C exists between the air inlet direction and the deflection direction of the guide vanes, causing some of the airflow entering between the guide vanes 6 to be blocked and diverted by the sidewalls of the guide vanes, thereby causing a small amount of purified air to return to the cyclone's reverse diversion section and rotate downward. Because the forward inclination of the guide vanes 6 is the same as the rotation direction of the centrifugal impeller 8, the direction of rotation of the purified air that is diverted back is the same as that of the inner cyclone, preventing the difference in the rotation directions of the inner and outer cyclones from affecting the centrifugal dust removal effect.

[0049] Specifically, the cyclone reverse diversion section 12 is connected to the dust collecting box 3 through the dust collecting port 16, is connected to the space outside the bottom of the shell 1 through the air inlet tube 2, and is connected to the exhaust section 13 through the lateral air inlet channel 61 and the lateral air outlet channel 62.

[0050] Specifically, refer to Figure 1 and Figure 4As shown, a fixed plate 5 is threadedly fixedly connected to a vertically downwardly mounted drive motor 7, located parallel to the center of the retaining ring 4. The rotating shaft of the drive motor 7 extends vertically downward through an axial hole (not shown) at the center of the fixed plate 5 and into the inner side of the inner circle surrounded by the guide vanes 6. A centrifugal impeller 8 is fixedly sleeved thereon, axially positioned within the cyclone reverse flow diversion section 12. The upper end of the centrifugal impeller 8 passes through the inner circular hole of the retaining ring 4 and is located on the inner side of the lateral air inlet channel 61. The lower end of the centrifugal impeller 8 is located above the upper opening of the air inlet cylinder 2.

[0051] It should be noted that in this embodiment, the rotating shaft of the drive motor 7 is used as the drive shaft connected to the centrifugal impeller 8. This design is merely a preferred embodiment of the present invention and does not limit the present invention. In other embodiments, the drive motor 7 can be disposed outside the housing 1 and connected to the drive shaft rotatably mounted on the fixed plate 5 via a transmission mechanism to drive the centrifugal impeller 8 to rotate.

[0052] Specifically, the centrifugal impeller 8 of the present invention is preferably a multi-blade forward-inclined impeller. The use of a multi-blade forward-inclined impeller can increase the angular velocity of the airflow rotation, thereby increasing the centrifugal acceleration of the inhalable particulate impurities in the dust-laden air and improving the centrifugal dust removal effect of the centrifugal impeller 8.

[0053] Specifically, refer to Figure 3 and Figure 8 As shown, the centrifugal impeller 8 of the present invention includes a top connecting plate 81 fixedly connected to the rotating shaft of the drive motor 7 and having an overall circular plate-like structure; a bottom fixing member 83, parallel to and opposite to the top connecting plate 81, having a circular hollow dust-laden air inlet 82 in the middle; and a total of 16 forward-inclined blades 84 evenly distributed between the top connecting plate 81 and the bottom fixing member 83. The forward-inclined blades 84 are axially distributed in a clockwise direction around the periphery of the dust-laden air inlet to form an axial air inlet channel 85 in the middle of the centrifugal impeller 8. The ratio (B / d) of the diameter B of the axial air inlet channel 85 to the radial width d of the centrifugal impeller 8 is between 0.2 and 0.8.

[0054] Preferably, the structure of the bottom fixing member 83 in this embodiment is a fixed ring structure. This fixed ring structure design not only ensures that the dust-laden air inlet 82 is reserved in the middle, but also can form additional dust-laden air channels into the interior of the centrifugal impeller in the gaps between the rings, thereby effectively increasing the air intake.

[0055] Specifically, refer to Figure 8As shown, in the present invention, the ratio M / d of the axial height M of the centrifugal impeller 8 to the radial width d of the centrifugal impeller 8 is between 0.5 and 3, the ratio A / M of the axial height A of the guide vane 6 to the axial height M of the centrifugal impeller 8 is between 0.1 and 0.25, and the ratio P / d of the inner diameter P (approximately equal to the inner diameter of the inner hole of the packing ring 4) surrounded by the guide vane 6 to the radial width d of the centrifugal impeller 8 is between 1.1 and 1.5.

[0056] The device of the present invention is based on the principle of cyclone reverse flow separation. Centrifugal impeller 8 and guide vanes 6 separate the airflow within the cyclone reverse flow section 12 into inner and outer cyclones for gas-solid separation and sedimentation. The aforementioned design of the centrifugal impeller 8 and guide vanes 6 achieves improved gas-solid separation and makes the device suitable for dust-laden air containing particulate impurities of varying sizes.

[0057] Preferably, the aperture of the inner circular hole of the isolation ring 4 of the present invention is not less than the radial cross-sectional diameter of the air inlet tube 2 to ensure that the centrifugal impeller 8 can suck the dust-laden air into the cyclone reverse diversion section 12 through the air inlet tube 2 to the greatest extent, thereby increasing the air intake and exhaust volume of the device of the present invention.

[0058] Specifically, refer to Figure 1 、 Figure 2 and Figure 4 As shown, the upper portion of the housing 1 is open, forming an exhaust port 17 with an aperture equal to the inner diameter of the housing 1. The upper portion of the sidewall of the housing 1, together with the isolation ring 4, guide vanes 6, and fixing plate 5, constitute the exhaust section 13. Clean air generated by the diversion in the cyclone reverse diversion section 12 enters the exhaust section 13 through the lateral inlet passage 61 and lateral outlet passage 62 between the guide vanes 6 and is ultimately discharged outward through the exhaust port 17.

[0059] The overall structure of the device of the present invention is concise and simple. The shell 1 adopts a cylindrical axial through-type design. There are no protruding or protruding parts on the outside of the shell 1, which is conducive to installing the device of the present invention in pipelines and culverts with limited space, and is convenient for construction and installation.

[0060] At the same time, the device of the present invention replaces the cyclone dust collector of the existing cyclone centrifugal dust removal device with a cyclone direction diversion section to achieve the function of cyclone centrifugal dust removal. Compared with the existing cyclone centrifugal dust removal device, the structure of the device of the present invention is more concise and simple, and does not require external cyclone dust collectors and circulating air ducts and other structures. The noise and vibration during actual operation are lower. In addition, the present invention eliminates structures such as cyclone dust collectors and circulating air ducts and can effectively reduce the power consumption of the drive motor 7. Under the same power consumption state, greater ventilation and centrifugal dust removal effects can be obtained, which greatly reduces the cost of production and manufacturing and the cost of use and maintenance, which is conducive to comprehensively promoting the device of the present invention to the market at a lower price, reducing users' equipment investment and use costs, and creating better environmental protection, economic and social value.

[0061] Moreover, since the device of the present invention does not require external cyclone dust collectors and circulating air ducts and other structures, the overall volume, height and footprint of the device of the present invention are smaller, and the space requirements for the site of use are not high. It can be installed in a relatively small area for use, and the use space is not limited, and the application range is wider.

[0062] The forward inclination direction of the guide vanes 6 of the device of the present invention is the same as the rotation direction of the centrifugal impeller 8, ensuring that the airflow radially separated from the upper end of the centrifugal impeller 8 can enter the lateral air inlet channel 61 between the guide vanes 6 at a certain angle, and ensuring that the airflow entering the guide vanes 6 through the lateral air inlet channel 61 can be blocked and guided by the curved surface between the guide vanes 6 for diversion.

[0063] Specifically, refer to Figures 4 to 7 As shown, the device of the present invention is based on an inner and outer cyclone reverse flow air dust removal method, which specifically includes the following steps:

[0064] The first step is to inhale dust-laden air: the drive motor 7 drives the centrifugal impeller 8 to rotate along the forward tilt direction of the guide blade to reduce the air pressure in the cyclone reverse diversion section 12, thereby axially inhaling the dust-laden air outside the bottom of the shell 1 through the air inlet 14 and the air inlet cylinder 2 into the axial air inlet channel 85 of the centrifugal impeller 8 in the cyclone reverse diversion section 12.

[0065] The second step is the generation of inner and outer cyclones: the dust-laden air entering through the axial air inlet channel 85 is driven by the centrifugal impeller 8 to rotate upward at high speed along the air duct between the forward-inclined blades 84, forming an inner cyclone with a rotation direction in the same direction as the rotation of the centrifugal impeller 8 and an axial direction in the same direction as the air inlet. Driven by the centrifugal impeller 8, part of the airflow in the inner cyclone rotates and rises to the upper end of the centrifugal impeller 8 and, under the action of centrifugal force, enters between the guide vanes 6 through the lateral air inlet channel 61. Under the action of the guide vanes 6, the airflow is split into two parts. One part follows the guide vanes 6 through the lateral air outlet channel 62 into the exhaust section 13 and is discharged outward through the exhaust port 17. The other part is blocked by the curved surface of the guide vanes 6 at the lateral air inlet channel 61, diverted downward and returned to the cyclone reverse diversion section 12, driving the airflow outside the centrifugal impeller 8 to rotate downward, forming an outer cyclone with a rotation direction in the same direction as the rotation of the centrifugal impeller 8 and an axial direction opposite to the air inlet, thus forming an inner and outer cyclone reverse diversion effect.

[0066] The third step is the separation of gas and solid phases of dust-laden air: Since the materials with different masses and densities in the inner cyclone are subjected to different centrifugal accelerations a of the centrifugal impeller 8 during the rotating upward process, the centrifugal acceleration a=r*w 2 , where r represents the centrifugal radius and w represents the angular velocity, refer to Figure 7As shown in the graph, this shows the variation in centrifugal acceleration a of the airflow at different locations within the same horizontal plane within the cyclone's reverse flow section 12. From this formula and the graph, it can be inferred that the centrifugal acceleration a of the inhalable particulate matter in the inner cyclone reaches its minimum value near the axial air inlet passage 85 (where r is minimum) and its maximum value near the edge of the centrifugal impeller 8 (where r is maximum). By appropriately adjusting the design of the centrifugal impeller 8, different centrifugal accelerations a can be provided for dust-laden air containing particulate matter of varying particle sizes at the same speed of the drive motor 7.

[0067] Reference Figure 7 As shown, curve S in this figure reflects the entire sedimentation curve of the airflow within the cyclone reverse diversion section 12, through the inner cyclone, external airflow, and outer cyclone. Combining this figure with common knowledge, it can be seen that the greater the mass and density of a substance, the greater its inertia, and the greater the impact of centrifugal acceleration a. Therefore, given a certain structure and rotational speed of the centrifugal impeller 8, inhalable particulate impurities with greater mass and density will have a faster radial sedimentation rate within the air duct of the centrifugal impeller 8. Compared with materials with smaller mass and density, these particles will first move radially to the periphery of the centrifugal impeller 8, forming the external airflow. Under the reverse push of the external cyclone and the action of gravity, they will settle along the side wall of the housing 1 through the dust collection port 16 and into the dust collection box 3.

[0068] Similarly, the clean air with small mass and density after the separation of inhalable particulate impurities cannot radially settle to the outside of the centrifugal impeller 8 to form external airflow at the same time due to the small centrifugal acceleration a it is subjected to. It can only continue to rotate axially with the internal cyclone under the drive of the centrifugal impeller 8 and rise to the upper end of the centrifugal impeller 8 and enter the lateral air inlet channel 61 under the action of centrifugal force.

[0069] The clean air is divided into two parts at the lateral air inlet channel 61 of the guide vane 6. Most of the clean air is discharged to the outside of the shell 1 through the lateral air outlet channel 62 and the exhaust port 17 to achieve the purpose of obtaining purified air. The other part of the airflow returns to the cyclone reverse diversion section 12 under the side blocking and guiding action of the guide vane 6 and drives the external airflow with a large dust content that has radially settled outside the centrifugal impeller 8 to rotate and descend to form an external cyclone. During the rotation and descent process, the external cyclone is blocked by the side wall of the shell 1 and under the action of gravity, and finally settles in the dust collecting box 3 through the dust collecting port 16.

[0070] According to aerodynamic analysis, it is found that the axial velocity V of the airflow on the radial cross section of the cyclone reverse diversion section 12 of the device of the present invention is different at different locations, such as Figure 7 As shown in the curve diagram, the airflow has a maximum axial velocity V at the axial air inlet channel 85, has a reverse axial velocity V between the outer side of the centrifugal impeller 8 and the side wall of the housing 1, and is zero at the intersection of the two near the periphery of the centrifugal impeller 8.

[0071] thus Figure 7 It can be inferred that the airflow in the inner cyclone undergoes radial and axial settling motion during its upward rotation, driven by the combined effects of centrifugal force and gravity. Larger, more dense, and more respirable particulate impurities experience a much greater centrifugal acceleration a than clean air, resulting in a faster radial settling velocity. Therefore, by ensuring that the impurities radially settle to the outside of centrifugal impeller 8 before they ascend axially with the airflow to the upper end of centrifugal impeller 8, forming an external airflow, gas-solid phase separation can be achieved during the inner cyclone's axial ascent, ultimately allowing the impurities to settle into dust box 3 under the drive of the outer cyclone and the action of gravity.

[0072] Step 4: Part of the outer cyclone flows into the inner cyclone: Most of the outer cyclone settles into the dust box 3 through the dust collection port 16 due to the side wall of the housing 1 and gravity, while a small portion of the outer cyclone flows into the inner cyclone near the upper end of the air inlet duct 2 and the bottom end of the centrifugal impeller 8, achieving a circulating dust removal effect. Because there is a certain gap between the upper end of the air inlet duct 2 and the bottom end of the centrifugal impeller 8 in the device of the present invention, a low-pressure area is formed at the bottom of the centrifugal impeller 8 during its rotation. Therefore, a small portion of the outer cyclone flows into the inner cyclone through the gap between the upper end of the air inlet duct 2 and the bottom end of the centrifugal impeller 8.

[0073] Compared with the existing cyclone centrifugal dust removal device, the present invention utilizes the gap between the air inlet tube 2 and the bottom of the centrifugal impeller 8 to connect the outer cyclone with the inner cyclone, replacing the circulating air tube of the existing cyclone centrifugal dust removal device. The overall structural design is more compact and ingenious, fully utilizing the internal space of the shell 1, and achieving a better circulating dust removal effect.

[0074] According to the above steps, under the premise of a certain speed of the driving motor 7 and the total air volume, as long as the structure of the guide vane 6 and the centrifugal impeller 8 in the device of the present invention is appropriately adjusted and designed according to the particle size, mass or density of the inhalable particulate impurities contained in the dust-laden air, so that particulate impurities of different masses and densities can obtain appropriate centrifugal acceleration a under the action of the centrifugal impeller 8 and the guide vane 6, and the axial velocity V of the airflow in the cyclone reverse diversion section 12 is controlled, the radial and axial settling velocities of the particulate impurities can be effectively controlled, ensuring that the particulate impurities in the dust-laden air can move radially to the outside of the centrifugal impeller 8 to form an external airflow before the axial velocity V of the airflow reaches zero, compared with clean air.

[0075] Therefore, in order to enable the device of the present invention to be used for purifying dusty air containing impurities of different particle sizes, it is necessary to use the following methods to specifically adjust and design the specifications and dimensions of the various components of the device of the present invention:

[0076] A. When separating dusty air containing impurity particles with a diameter of 5 microns or more, the ratio B / d of the diameter B of the axial air inlet channel 85 of the centrifugal impeller 8 to the radial width d of the centrifugal impeller 8 is between 0.2 and 0.5, and the ratio M / d of the axial height M of the centrifugal impeller 8 to the radial width d of the centrifugal impeller 8 is between 0.5 and 1.

[0077] B. When separating dusty air containing impurity particles with a diameter of less than 5 microns, the ratio of the diameter of the axial air inlet channel 85 of the centrifugal impeller 8 to the radial width of the centrifugal impeller 8 is between 0.5 and 0.8, and the ratio of the axial height of the centrifugal impeller 8 to the radial width of the centrifugal impeller 8 is between 1 and 3.

[0078] When separating and purifying impurity particles with a particle size of more than 5 microns, the airflow needs to have a larger centrifugal acceleration a. Under the premise that the speed of the driving motor 7 remains unchanged, the radial sedimentation time and axial sedimentation time of the particulate impurities can be regulated by reducing the air outlet speed and the axial velocity V of the airflow, ensuring that the particulate impurities can move radially to the outside of the centrifugal impeller 8 to form an external airflow when the axial velocity reaches zero. Similarly, when separating and purifying impurity particles with a particle size of less than 5 microns, the centrifugal acceleration a of the airflow should not be too high. Under the premise that the speed of the driving motor 7 and the total air volume remain unchanged, the radial sedimentation time and axial sedimentation time of the particulate impurities can be regulated by appropriately increasing the air outlet speed and the axial velocity V of the airflow, ensuring that the particulate impurities can move radially to the outside of the centrifugal impeller 8 to form an external airflow when the axial velocity reaches zero.

[0079] According to the above requirements, when actually designing the structure and size of the guide vane 6 and the centrifugal impeller 8 of the device of the present invention:

[0080] Preferably, refer to Figure 8 As shown, the optimal ratio D / d of the inner diameter D of the housing 1 and the radial width d of the centrifugal impeller 8 is between 1.2 and 1.8.

[0081] This structural design can provide appropriate external space for the axial sedimentation of the external airflow, which is beneficial to improving the sedimentation effect of particulate impurities and improving the purification and dust removal efficiency of the device of the present invention.

[0082] Preferably, refer to Figure 5 As shown, the optimal value of the deflection angle C of the guide vane 6 is between 30° and 60°.

[0083] This structural design ensures that the airflow radially ejected from the upper end of the centrifugal impeller 8 can enter between the guide vanes 6 at a suitable angle, providing a suitable diversion angle for the reverse diversion of the airflow.

[0084] Preferably, refer to Figure 8As shown, the optimal ratio N / d of the total number of guide vanes 6 to the radial width d of the centrifugal impeller 8 is between 0.2 and 0.8. Preferably, the radial width d of the centrifugal impeller 8 is expressed in mm, with 30 mm ≤ d ≤ 2000 mm. When the radial width of the centrifugal impeller 8 is greater than 2000 mm, the optimal ratio N / d of the total number of guide vanes 6 to the radial width d of the centrifugal impeller 8 is greater than 0.6.

[0085] The specific number of guide vanes 6 will directly affect the air output, and the spacing between adjacent guide vanes 6 has a direct impact on the reverse diversion of the airflow. The above structural design can maximize the total air output of the guide vanes 6 and ensure the effect of reverse diversion of the airflow.

[0086] Preferably, refer to Figure 8 As shown, the optimal ratio P / d of the inner diameter P of the guide vane 6 to the radial width d of the centrifugal impeller 8 is between 1.1 and 1.5.

[0087] Preferably, the optimal ratio Q / P of the outer diameter Q of the guide vane 6 to the inner diameter P of the guide vane 6 is between 1.1 and 1.5, and the optimal ratio A / M of the height A of the guide vane 6 to the height M of the centrifugal impeller 8 is between 0.1 and 0.25.

[0088] Preferably, the optimal ratio T / d of the diameter T of the air inlet cylinder 2 to the radial width d of the centrifugal impeller 8 is between 0.5 and 0.8.

[0089] Preferably, an optimal ratio Y / d of the distance Y between the upper end of the air inlet cylinder 2 and the bottom of the centrifugal impeller 8 to the radial width d of the centrifugal impeller 8 is between 0.1 and 0.5.

[0090] Preferably, the optimal ratio Y / d of the height X of the upper end of the air inlet cylinder 2 exposed outside the upper end cover 15 and the radial width d of the centrifugal impeller 8 is between 0.1 and 0.5.

[0091] Through the above-mentioned structural design, the design of the structures of various parts of the device of the present invention is optimized, ensuring the air inlet and outlet volume and the cyclone reverse diversion dust removal effect of the device of the present invention, so that the device of the present invention can be applied to dust-laden air containing impurities of different particle sizes.

[0092] The above embodiment is only for the purpose of clearly illustrating a specific embodiment of the present invention, and is not intended to limit the embodiment of the present invention. For those skilled in the art, based on the present invention, other adjustments or changes to the housing 1, the air inlet dust collection section 11, the cyclone reverse diversion section 12, the exhaust section 13, etc. can be deduced and summarized, or some other methods of use deduced and summarized based on the present invention are not listed here one by one. Any modification, replacement or improvement made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. An inner and outer cyclone reverse flow air dust removal device, comprising a housing, characterized in that: The shell is divided into an air inlet dust collecting section, a cyclone reverse diversion section and an exhaust section which are interconnected. The air inlet dust collecting section includes an air inlet cylinder arranged at the bottom of the shell and a dust collecting box arranged outside the air inlet cylinder, and the upper end cover of the dust collecting box is provided with a dust collecting port; the cyclone reverse diversion section includes a sealing ring which is radially fixed to the upper part of the side wall of the shell and is coaxial with the air inlet cylinder, a fixing plate which is radially fixed above the sealing ring and has a diameter larger than the aperture of its inner circular hole and smaller than the inner diameter of the shell, and a number of guide plates which are tightly axially arranged between the fixing plate and the sealing ring, and the guide plates between adjacent ones are at one end of the inner circular hole of the sealing ring. A lateral air inlet channel is formed, and a lateral air outlet channel is formed at one end of the edge of the fixed plate; a drive shaft is provided on the fixed plate, to which is connected a centrifugal impeller axially located in the cyclone reverse diversion section, the upper end of the centrifugal impeller passes through the inner circular hole of the sealing ring and is located correspondingly on the inner side of the lateral air inlet channel, and the bottom end is located correspondingly on the upper part of the air inlet cylinder; the guide vane is an inwardly inclined forward structure, and the forward inclination direction of one end of the lateral air inlet channel is the same as the rotation direction of the centrifugal impeller to divert the airflow at the opening of the lateral air inlet channel; the exhaust section includes an exhaust port, and the exhaust port is connected to the cyclone reverse diversion section through the lateral air outlet channel; The ratio of the axial height to the radial width of the centrifugal impeller is between 0.5 and 3, the ratio of the axial height of the guide vane to the axial height of the centrifugal impeller is between 0.1 and 0.25, and the ratio of the inner diameter of the circle enclosed by the guide vane to the radial width of the centrifugal impeller is between 1.1 and 1.5; The centrifugal impeller includes a top connecting plate fixedly connected to the drive shaft, a bottom fixing piece parallel to and opposite to the top connecting plate and having a dust-laden air inlet in the middle, and a plurality of forward-inclined blades evenly distributed between the top connecting plate and the bottom fixing piece. The forward-inclined blades are axially distributed in a clockwise or counterclockwise direction around the periphery of the dust-laden air inlet to form an axial air inlet channel in the middle of the centrifugal impeller.

2. The inner and outer cyclone reverse flow air dust removal device according to claim 1, characterized in that: The centrifugal impeller is a multi-blade forward-inclined impeller.

3. The inner and outer cyclone reverse flow air dust removal device according to claim 1, characterized in that: An air inlet is provided in the middle of the bottom surface of the shell, the air inlet tube is axially connected to the air inlet, the upper end cover is radially fixedly sleeved on the upper part of the outer wall of the air inlet tube, and a gap is left between the outer peripheral edge of the upper end cover and the side wall of the shell to form the dust collecting port, the bottom surface, side wall, outer wall of the air inlet tube, and upper end cover of the shell together constitute the dust collecting box.

4. The inner and outer cyclone reverse flow air dust removal device according to claim 1, characterized in that: The diameter of the inner circular hole of the isolation ring is not less than the diameter of the air inlet cylinder.

5. The inner and outer cyclone reverse flow air dust removal device according to claim 1, characterized in that: The ratio of the diameter of the axial air inlet channel to the radial width of the centrifugal impeller is between 0.2 and 0.

8.

6. A dust removal method using the inner and outer cyclone reverse flow air dust removal device according to claim 1, characterized in that The following steps are included: The first step is to inhale dust-laden air: the drive shaft, driven by an external power source, drives the centrifugal impeller to rotate along the forward tilt direction of the guide vane to reduce the air pressure in the cyclone reverse diversion section, thereby inhaling the dust-laden air outside the bottom of the housing into the axial air inlet channel of the centrifugal impeller through the air inlet tube; The second step is the generation of internal and external cyclones: the dust-laden air entering through the axial air inlet channel is driven by the centrifugal impeller to rotate and rise at high speed along the air duct between the forward-inclined blades, forming an internal cyclone with the same rotation direction as the centrifugal impeller and the same axial direction as the air inlet direction; The airflow that rotates and rises to the upper end of the centrifugal impeller enters between the guide vanes through the lateral air inlet channel under the action of centrifugal force. The airflow is split into two parts under the action of the guide vanes, one part of which follows the guide vanes through the lateral air outlet channel into the exhaust section and is discharged outward through the exhaust port, while the other part is blocked by the side of the guide vane at the opening of the lateral air inlet channel, split and flows downward back into the cyclone reverse diversion section and drives the external airflow of the centrifugal impeller to rotate and descend, thereby forming an external cyclone on the outside of the centrifugal impeller with a rotation direction that is the same as the rotation direction of the centrifugal impeller and an axial direction that is opposite to the air inlet direction, forming an internal and external cyclone reverse diversion effect; The third step is the separation of the gas-solid phase of the dust-laden air: the substances with different masses and densities in the inner cyclone are subjected to different centrifugal accelerations of the centrifugal impeller during the rotating upward process. The greater the mass and density of the substance, the greater the centrifugal acceleration, and the faster the radial sedimentation speed in the centrifugal impeller air duct. The substances with smaller mass and density can first move to the periphery of the centrifugal impeller to form external airflow and settle into the dust collecting box through the dust collecting port along the side wall of the shell under the reverse push of the outer cyclone and the action of gravity; similarly, the clean air with smaller mass and density is subjected to centrifugal acceleration. The acceleration is small, and at the same time it cannot radially separate from the centrifugal impeller to form an external airflow. Instead, it continues to rotate axially with the inner cyclone and rises to the upper end of the centrifugal impeller and enters the lateral air inlet channel under the action of centrifugal force. The clean air is split into two parts at the lateral air inlet channel opening of the guide vane. Most of the clean air is discharged to the outside of the shell through the lateral air outlet channel and the exhaust port, and the other part returns to the cyclone reverse diversion section and drives the dust-laden external airflow that has radially settled outside the centrifugal impeller to rotate downward to form an outer cyclone and finally settle axially in the dust collecting box. The fourth step is that part of the outer cyclone flows into the inner cyclone: most of the outer cyclone settles into the dust collecting box through the dust collecting port under the action of the side wall of the shell and gravity, and a small part of the outer cyclone flows into the inner cyclone near the upper end of the air inlet tube and the bottom end of the centrifugal impeller to realize circulating dust removal.

7. The method for removing dust from an air stream by reverse flow of inner and outer cyclones according to claim 6, characterized in that: The method also includes a method for adjusting the specifications and dimensions of various components of the dust removal device when purifying dust-laden air containing particles of different sizes, including: A. When separating dusty air containing impurity particles with a diameter of 5 microns or more, the ratio of the diameter of the axial air inlet channel of the centrifugal impeller to the radial width of the centrifugal impeller is between 0.2 and 0.5, and the ratio of the axial height of the centrifugal impeller to the radial width of the centrifugal impeller is between 0.5 and 1; B. When separating dusty air containing impurity particles with a diameter of less than 5 microns, the ratio of the diameter of the axial air inlet channel of the centrifugal impeller to the radial width of the centrifugal impeller is between 0.5 and 0.8, and the ratio of the axial height of the centrifugal impeller to the radial width of the centrifugal impeller is between 1 and 3.

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