Device for preventing dust deposition in pneumatic conveying pipeline

Abstract

The invention discloses a device for preventing dust deposition in a pneumatic conveying pipeline, which comprises an anti-deposition assembly positioned in the pneumatic conveying pipeline, the anti-deposition assembly comprises a series of blades arranged in parallel at equal intervals, and the first blade is fixed at the bottom of the pneumatic conveying pipeline; the connecting line of the centers of the middle blades is marked as a center line, and the center line dip angle and the blade dip angle meet the requirement; and the highest point of the previous layer of blades is equal to or higher than the lowest point of the windward side of the next layer of blades, so that dust is rebounded by a series of blades under the action of airflow and is raised for the second time. Dust deposition at the bottom of the pneumatic conveying pipeline is greatly reduced through inertia shielding and rebounding of dust particles on the surface of the anti-deposition assembly structure and the reentrainment of dust under the inclined layout of the anti-deposition assembly to adapt to common dust pneumatic conveying pipeline elements such as elbows and variable-diameter pipelines; and the device has the characteristic of accurately controlling dust deposition of the pneumatic dust conveying pipeline system.

Description

Technical Field

[0001] This invention relates to the field of pneumatic dust conveying technology, and in particular to a device for preventing dust deposition in pneumatic conveying pipelines. Background Technology

[0002] Pneumatic conveying technology for powders has been widely adopted since its inception due to its advantages such as high production efficiency, flexible pipeline layout, ease of centralized control, and automated processes. However, long-term use of pneumatic conveying pipelines can lead to the gradual accumulation of dust and particulate matter. This can pose a safety hazard, especially for explosive dust particles, and may even result in pipe blockages, thus disrupting the safe production and operation of industrial and commercial enterprises dealing with powder. Therefore, reducing or preventing pipeline blockages and fundamentally avoiding the deposition of dust and particulate matter in pneumatic conveying pipelines is an urgent problem that needs to be solved.

[0003] To prevent dust accumulation in pneumatic conveying pipelines, control methods can be categorized into active and passive control. Passive control involves directly stopping the system when dust deposition or pipeline blockage occurs during production, cleaning the pipeline, or using air pumps (such as utility model patent CN202421108297.9) for high-pressure ventilation to clear blockages. Undoubtedly, passive control will affect continuous production. Active control, on the other hand, involves studying the particle transport state within the pneumatic conveying system to fundamentally prevent and control dust deposition, thereby improving the stability of the system and reducing energy consumption. Clearly, active control is theoretically superior to passive control. Therefore, many technical measures have been proposed for the active control of axial and radial flow in pneumatic pipelines, as illustrated by patents CN202421081927.8, CN202420774656.8, and CN202421091736.X. The above methods can improve the suspension characteristics of conveyed particles and enhance the stability of the dust pneumatic conveying system. However, further improvements are needed in terms of the stability of flow field control and the adaptability of the installation to operating conditions. How to achieve anti-clogging design without significantly increasing the complexity of the dust pneumatic conveying system remains to be solved. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned problems in the prior art by providing a device for preventing dust deposition in pneumatic conveying pipelines. This is achieved by installing a novel louvered anti-deposition component with a gradually narrowing flow channel in the pneumatic conveying pipeline. Using an inertial separation method, dust particles accumulated at the bottom of the pipeline are separated under the inertial force of the airflow and reflected to the upper part of the pipeline by the louvered anti-deposition component. This allows the dust particles accumulated at the bottom of the pipeline to remix with the conveying airflow, thereby improving the suspension characteristics of the conveyed particles.

[0005] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0006] A device for preventing dust deposition in a pneumatic conveying pipeline includes an anti-deposition component located within the pneumatic conveying pipeline. The anti-deposition component comprises a series of equally spaced parallel blades, with the bottom blade being the first blade and fixed to the bottom of the pneumatic conveying pipeline. The other blades are intermediate blades. The line connecting the centers of all intermediate blades is denoted as the centerline, and the angle between the centerline and the central axis of the pneumatic conveying pipeline from the inlet to the outlet is denoted as the centerline inclination angle. The angle between the blade and the central axis of the pneumatic conveying pipeline, from the inlet to the outlet, is denoted as the blade tilt angle. , The highest point of the preceding layer of blades is equal to or higher than the lowest point of the windward side of the following layer of blades, causing dust to be re-lifted by the airflow after a series of bounces from the blades.

[0007] As mentioned above, the blades have a plate-like structure, and the windward side of the blades is hardened.

[0008] As mentioned above, the surface of the blade is streamlined.

[0009] As mentioned above, the height of the anti-deposition component is 40% to 60% of the diameter of the pneumatic conveying pipeline.

[0010] As described above, the anti-deposition components are arranged in the long straight section, at the variable cross-section, or at the bend of the pneumatic conveying pipeline.

[0011] As mentioned above, the pneumatic conveying pipeline is a circular cross-section pipeline, a rectangular cross-section pipeline, or a variable cross-section pipeline.

[0012] As described above, the bottom blades, except for the top edge, are connected to the inner wall of the pneumatic conveying pipe, and the left and right sides of the middle blades are connected to the inner wall of the pneumatic conveying pipe.

[0013] As described above, centerline inclination angle The range is 10° to 45°.

[0014] As mentioned above, the height of the bottom blade is 2 to 3 times the thickness of dust deposition when no anti-deposition component is installed.

[0015] Multiple anti-deposition components are distributed at intervals along the length of the pneumatic conveying pipeline as described above, and the spacing between the anti-deposition components satisfies the following relationship:

[0016] ,

[0017] in The spacing between adjacent louver anti-deposition components along the wall of the pneumatic conveying pipeline. The velocity of the airflow transported within the pneumatic conveying pipeline. The effective time for dust to settle from the top to the bottom of the pneumatic conveying pipe.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] This invention proposes a novel louvered anti-deposition component structure with a tapered flow channel to improve the suspension characteristics of dust particles in pneumatic conveying pipelines. By utilizing the inertial rebound of dust particles on the surface of the anti-deposition component structure and the secondary dust-raising effect of the tilted arrangement of the component, dust deposition at the bottom of the pneumatic conveying pipeline is significantly reduced. The structure features a small footprint, no additional complex dust removal and separation mechanisms, and low operating costs. Furthermore, by adjusting the structure of the anti-deposition component, such as bending or twisting the arrangement of the blades, it can adapt to common pneumatic conveying pipeline components such as elbows and variable-diameter pipes. Compared to conventional dust deposition prevention measures, this offers diverse installation and arrangement options and precise control of dust deposition in the pneumatic conveying pipeline system. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a device for preventing dust deposition in a pneumatic conveying pipeline according to the present invention, wherein H is the distance from the bottom of the pneumatic conveying pipeline to the intersection of the bottom blade and the center line in the anti-deposition component; d is the spacing between the blades in the anti-deposition component along the center line direction; w is the width of the blades in the anti-deposition component along the inclined direction; and h is the thickness of the blades in the anti-deposition component. The blade tilt angle represents the angle between the blade and the central axis of the pneumatic conveying pipeline in the anti-deposition assembly. The centerline inclination angle represents the angle between the centerline of the anti-deposition assembly's blades arranged in a row and the central axis of the pneumatic conveying pipeline.

[0021] Figures 2a-2c This is a schematic diagram showing the relative positions of adjacent blades of the anti-deposition component described in this invention. Figure 2a Blade tilt angle Centerline tilt angle Schematic diagram of the relative installation positions of adjacent blades of the anti-deposition component; Figure 2b Blade tilt angle Centerline tilt angle Schematic diagram of the relative installation positions of adjacent blades of the anti-deposition component; Figure 2c Blade tilt angle Centerline tilt angle A schematic diagram showing the relative installation positions of adjacent blades of the anti-deposition component.

[0022] Figure 3a~ Figure 3d This is a comparison diagram showing the dust conveying effect before and after using the device for preventing dust deposition in pneumatic conveying pipelines described in this invention; wherein, Figure 3a This diagram illustrates the dust conveying effect without anti-deposition components. Figure 3b To set the blade tilt angle Centerline tilt angle The image shows the dust conveying effect of the anti-deposition component. Figure 3c To set the blade tilt angle Centerline tilt angle The image shows the dust conveying effect of the anti-deposition component. Figure 3d To set the blade tilt angle Centerline tilt angle The diagram shows the dust conveying effect of the anti-deposition component, where n is the total number of blades.

[0023] Figures 4a-4d A comparison chart shows the dust conveying effect of using multiple anti-deposition components in the device for preventing dust deposition in pneumatic conveying pipelines as described in this invention; wherein, Figure 4a This is a diagram illustrating the dust conveying effect without anti-deposition components. Figure 4b The diagram shows the dust conveying effect when five anti-deposition components are set up. Figure 4c The diagram shows the dust conveying effect when six anti-deposition components are set up. Figure 4d A diagram illustrating the dust conveying effect when six anti-deposition components are installed; The distance between adjacent anti-deposition components along the length of the pneumatic conveying pipeline is expressed in meters (m).

[0024] Figure 1 In the middle, 1 – pneumatic conveying pipe inlet, 2 – pneumatic conveying pipe, 3 – anti-deposition component, 301 – bottom blade, 302 – middle blade, 4 – pneumatic conveying pipe outlet. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] Example 1:

[0027] A device for preventing dust deposition in pneumatic conveying pipelines, such as Figure 1 As shown, the pneumatic conveying pipeline 2 includes an anti-deposition component 3 located within it. The anti-deposition component 3 comprises a series of equally spaced parallel blades. The bottom blade 301 is the first blade and is fixed to the bottom of the pneumatic conveying pipeline 2. The other blades besides the bottom blade 301 are intermediate blades 302. The line connecting the centers of all intermediate blades 302 is called the centerline. The angle between the centerline and the central axis of the pneumatic conveying pipeline 2 from the inlet 1 to the outlet 4 is called the centerline inclination angle. The angle between the blade and the central axis of the pneumatic conveying pipe 2, from the inlet 1 to the outlet 4, is denoted as the blade tilt angle. , By arranging the blades in a stepped layer along the airflow direction, the height of the anti-deposition component 3 gradually increases along the airflow direction, the airflow channel between the anti-deposition component 3 and the inner wall of the pneumatic conveying pipe 2 gradually narrows, and the anti-deposition component 3 and the airflow channel form a certain taper.

[0028] In the anti-deposition component 3, the blades arranged sequentially along the airflow direction have progressively increasing layers. To prevent dust particles from leaking downstream when passing through the gaps between adjacent blades, the blade tilt angle is adjusted. The spacing between the blades ensures that the highest point of the preceding blade layer is equal to or higher than the lowest point of the windward side of the following blade layer. Figures 2a-2c As shown, the projected area of ​​the upper part of the blades of the current layer along the airflow direction to the lower part of the blades of the next layer is greater than 0. This ensures that while the airflow passes through the pneumatic conveying pipe 2, the blades of the previous layer partially block the blades of the next layer, so that the dust is re-lifted by the rebound of a series of blades under the action of the airflow. The bottom blade 301 fixed to the bottom of the pneumatic conveying pipe 2 ensures that no dust leaks to the downstream of the airflow. The top and bottom of the middle blade 302 are both left with gaps from the inner wall of the pneumatic conveying pipe 2.

[0029] After the dust-laden airflow enters the pneumatic conveying pipe 2 through the pneumatic conveying pipe inlet 1, the suspended dust in the airflow will gradually settle to the bottom of the pneumatic conveying pipe 2 as it is transported downstream. When the deposited dust at the bottom of the pneumatic conveying pipe 2 comes into contact with the bottom blade 301 of the anti-deposition component 3, the deposited dust will be re-raised by the airflow due to the blocking and rebound effect of the bottom blade 301. In order to prevent the re-raised dust particles from settling again, the intermediate blades 302 arranged in a certain angled row of the anti-deposition component 3 guide and rebound layer by layer, so that the re-raised dust particles are lifted to a certain height along the radial direction of the pneumatic conveying pipe 2, thereby prolonging the suspension residence time of the dust particles. Finally, the suspended dust-laden airflow is discharged through the pneumatic conveying pipe outlet 4.

[0030] Preferably, the blades are plate-type structures, and the windward side of the blades is hardened to increase surface wear resistance.

[0031] Preferably, the surface shape of the blade is streamlined to reduce flow separation, avoid turbulence, and reduce flow resistance.

[0032] Preferably, the height of the anti-deposition component 3 is 40% to 60% of the diameter of the pneumatic conveying pipe 2, which reduces flow resistance loss while ensuring that the suspended dust airflow has sufficient cross-sectional area to guarantee the conveying capacity of the pneumatic conveying pipe 2.

[0033] Preferably, the anti-deposition component 3 is arranged in the long straight section of the pneumatic conveying pipeline 2, but is not limited to the section with a variable cross-section or a bend.

[0034] Preferably, the pneumatic conveying pipe 2 is a circular cross-section pipe, but it is not limited to rectangular cross-section pipes or variable cross-section pipes.

[0035] Preferably, the anti-deposition component 3 extends upwards at an angle from the bottom of the pneumatic conveying pipe 2, with a centerline inclination angle of... The range is 10° to 45°.

[0036] Preferably, the bottom blade 301 of the anti-deposition component 3, except for the top edge, is connected to the inner wall of the pneumatic conveying pipe 2 (to prevent dust leakage, the bottom and sides of the bottom blade 301 are connected to the inner wall of the pneumatic conveying pipe 2), and the height of the bottom blade 301 is 2 to 3 times the dust deposition thickness when the anti-deposition component 3 is not installed.

[0037] There are various ways to fix the anti-deposition component 3 and the pneumatic conveying pipe 2. The simplest way is that the bottom blade 301 of the anti-deposition component 3, except for the top edge, and the left and right sides of the middle blade 302 are all welded to the inner wall of the pneumatic conveying pipe 2. After the anti-deposition component 3 and the pneumatic conveying pipe 2 are fixed, the airflow passes through the gap between the middle blades 302 when passing through the anti-deposition component 3. When the dust particles pass through the anti-deposition component 3 with the airflow, they collide and reflect with the anti-deposition component 3, making it difficult for them to pass through the gap between the middle blades 302. This causes the airflow and dust particles to separate. Under the action of the tilted anti-deposition component 3, the dust particles are lifted up again to avoid pipe blockage caused by dust deposition.

[0038] Example 2:

[0039] A device for preventing dust deposition in a pneumatic conveying pipeline includes multiple anti-deposition components 3 as described in Embodiment 1, spaced apart along the length direction (i.e., the central axis direction) of the pneumatic conveying pipeline 2. A certain distance is maintained between the anti-deposition components 3 to ensure airflow. When multiple anti-deposition components 3 are arranged consecutively within the pneumatic conveying pipeline 2, the spacing between the anti-deposition components 3 satisfies the following relationship:

[0040] ,

[0041] in The spacing between adjacent louver anti-deposition components along the wall of the pneumatic conveying pipeline. The velocity of the airflow transported within the pneumatic conveying pipeline. The effective time for dust to settle from the top to the bottom of the pneumatic conveying pipe.

[0042] Dust particles that are stirred up after passing through an anti-deposition component 3 will re-enter a free deposition state, such as... Figures 3a-3d As shown. To prevent dust from clogging the pipes, it should be stirred up again before it settles. Therefore, the spacing between multiple louver-type anti-deposition components 3 must meet certain conditions. If the spacing is too small, the flow resistance will be high; if the spacing is too large, the stirred-up dust will settle. Therefore, the above formula provides the spacing constraints between the multiple anti-deposition components 3 when they are arranged in a structural configuration.

[0043] Figures 3a-3dThe paper presents the settling of particles along the dust-laden airflow when the anti-deposition component 3 is installed in the pneumatic conveying pipeline 2. It can be seen that without the anti-deposition component 3 structure proposed in this invention, the suspended dust in the dust-laden airflow will quickly settle and always accumulate at the bottom of the pneumatic conveying pipeline 2. After installing the anti-deposition component 3 structure proposed in this invention, the suspended dust with a tendency to settle upstream of the anti-deposition component 3 is lifted up again under the action of the anti-deposition component 3, so that the dust-laden airflow can maintain the state of suspended dust and transport it downstream a longer distance.

[0044] Figures 4a-4d The paper presents the dust-laden airflow transport situation when multiple anti-deposition components 3 are installed at certain intervals in the pneumatic conveying pipeline 2. When the dust raised by the previous anti-deposition component 3 has a tendency to settle again, it is raised again by the next anti-deposition component 3, and so on, in a relay form to keep the dust-laden airflow in the pneumatic conveying pipeline 2 in a suspended state for downstream transport, thereby effectively overcoming the industry problem of dust deposition in long-distance pneumatic conveying pipelines 2.

[0045] like Figures 3a-3d As shown, there is a noticeable secondary dust re-entrainment phenomenon after the anti-deposition component 3. To completely avoid dust deposition at the bottom of the pneumatic conveying pipe 2, the installation spacing between multiple anti-deposition components 3 needs to be further reduced. However, this will increase the flow resistance of the airflow in the pneumatic conveying pipe 2, leading to increased energy consumption, and thus the actual overall efficiency may not be optimal. To achieve the optimal overall efficiency, Figures 4b-4d An optimized layout is provided, in which when dust re-raised by one anti-deposition component 3 shows a tendency to deposit again, it is re-raised by the next anti-deposition component 3. Figures 4b-4d The relatively dense dust at the bottom of the pneumatic conveying pipe is a display issue related to the calculated particle concentration. The particle concentration is significantly reduced compared to when there is no anti-deposition component 3, which is sufficient to allow these dust particles to flow further downstream with the airflow.

[0046] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A device for preventing dust deposition in a pneumatic conveying pipeline, comprising an anti-deposition component (3) located within the pneumatic conveying pipeline (2), characterized in that, The anti-deposition component (3) includes a series of equally spaced parallel blades. The bottom blade (301) is the first blade and is fixed to the bottom of the pneumatic conveying pipe (2). The other blades besides the bottom blade (301) are intermediate blades (302). The line connecting the centers of each intermediate blade (302) is called the centerline. The angle between the centerline and the central axis of the pneumatic conveying pipe (2) from the inlet (1) to the outlet (4) is called the centerline inclination angle. The angle between the blade and the central axis of the pneumatic conveying pipe (2) from the inlet (1) to the outlet (4) of the pneumatic conveying pipe is denoted as the blade tilt angle. , The highest point of the preceding blade is equal to or higher than the lowest point of the windward side of the following blade, causing dust to be re-lifted by the airflow after a series of bounces from the blades.

2. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, The blades have a plate-like structure, and the windward side of the blades is hardened.

3. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, The surface of the blade is streamlined.

4. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, The height of the anti-deposition component (3) is 40% to 60% of the diameter of the pneumatic conveying pipe (2).

5. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, The anti-deposition component (3) is arranged in the long straight section, variable cross section, or bend of the pneumatic conveying pipeline (2).

6. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, The pneumatic conveying pipeline (2) is a circular cross-section pipeline, a rectangular cross-section pipeline, or a variable cross-section pipeline.

7. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, The bottom blade (301) has its edges connected to the inner wall of the pneumatic conveying pipe (2) except for the top edge, and the left and right sides of the middle blade (302) are connected to the inner wall of the pneumatic conveying pipe (2).

8. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, The centerline inclination angle The range is 10° to 45°.

9. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, The height of the bottom blade (301) is 2 to 3 times the thickness of the dust deposition when the anti-deposition component (3) is not set.

10. The device for preventing dust deposition in a pneumatic conveying pipeline according to claim 1, characterized in that, Multiple anti-deposition components (3) are distributed at intervals along the length of the pneumatic conveying pipeline (2), and the spacing between the anti-deposition components (3) satisfies the following relationship: ， in The spacing between adjacent louver anti-deposition components along the wall of the pneumatic conveying pipeline. The velocity of the airflow transported within the pneumatic conveying pipeline. The effective time for dust to settle from the top to the bottom of the pneumatic conveying pipe.

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