Filter cartridge dust remover

Abstract

The filter cartridge dust remover comprises a plurality of filter cartridge units, each filter cartridge unit comprises a vertically-arranged filter cartridge and an induction nozzle assembly located over the filter cartridge, and each induction nozzle assembly comprises a nozzle and an air diffuser located under the nozzle; the air diffuser is of an integrated structure, is of a big-end-down water-drop-shaped structure and comprises a cone frustum structure part located on the upper portion and a hemisphere structure part located on the lower portion. The geometric central axis of the cone frustum structure part passes through the sphere center of the hemisphere structure part, and a central flow guide hole penetrating through the air diffuser in the axial direction is formed in the position of the geometric central axis of the cone frustum structure part. According to the filter cartridge dust remover, the overall blowing strength and blowing uniformity can be considered, airflow can be effectively induced and converged through the arrangement of the air diffuser of the water drop type structure and the central flow guide hole, and then the high dust removal efficiency and the good dust removal effect are achieved.

Description

Technical Field

[0001] The invention relates to a filter cartridge dust collector, in particular to a filter cartridge dust collector with a diffuser and adopting pulse jetting for dust cleaning, belonging to the technical field of dust removal. Background Art

[0002] The cartridge dust collector is a dust collector that uses a filter cartridge as a filter element. It uses the filter cartridge to filter the dust-laden gas and blocks the dust particles on the surface of the filter cartridge, thereby achieving the purpose of dust removal. The cartridge dust collector generally includes a shell, a filter cartridge, a cleaning system, an air inlet and an air outlet. The filter cartridge is generally made of fiber, cloth bag, ceramic and other materials. The working principle of the cartridge dust collector is: the dust-laden gas enters the dust collector from the air inlet of the dust collector, and after being filtered by the filter cartridge, the dust particles captured on the surface of the filter cartridge are removed by the cleaning system, and the clean gas is discharged through the air outlet. The cartridge dust collector is widely used in gas purification in industries such as steel, cement, mining, chemical, food, pharmaceutical, mechanical processing, and electric power due to its high dust removal efficiency, compact structure, and strong adaptability.

[0003] The cleaning system of the filter cartridge dust collector is a key component to ensure the continuous and efficient operation of the filter cartridge dust collector. The main function of the cleaning system is to remove the dust on the surface of the filter cartridge in a certain way when the dust accumulation on the surface of the filter cartridge reaches a certain level, so as to ensure that the filtration efficiency and resistance of the dust collector are maintained at a low level. The effective operation of the cleaning system can extend the service life of the filter cartridge and improve the overall performance of the filter cartridge dust collector. In the prior art, the cleaning system of the filter cartridge dust collector mostly adopts the pulse jet cleaning method. The pulse jet cleaning uses compressed air as a power source, and the timing and duration of the compressed air injection are controlled by the pulse valve. When the dust on the surface of the filter cartridge accumulates to a certain extent, the pulse valve opens rapidly, and the compressed air is sprayed into the interior of the filter cartridge through the nozzle at high speed in a very short time. The strong impact force causes the filter cartridge to expand rapidly and vibrate, thereby shaking off the dust attached to the surface. The shaken-off dust falls into the ash hopper and is discharged by the ash discharge mechanism.

[0004] During the pulse cleaning process, since the compressed air is sprayed into the filter cartridge at a high speed in a very short time, it is easy to cause negative pressure to form on the upper part of the filter cartridge, resulting in serious waste of filtration area, which in turn results in poor cleaning effect and easy damage to the filter cartridge. In order to solve this problem, there is a technical solution in the prior art to change the flow field of the soot blowing airflow by adding a diffuser directly below the nozzle, thereby achieving improved cleaning effect. The diffuser is usually a conical structure with a small top and a large bottom, which can force the jet to diverge around and change the flow field distribution of the soot blowing airflow. The conical diffuser can reduce the flow rate and flow velocity of the impact airflow, and induce more airflow to enter the filter cartridge by suction. Although the existing diffuser can improve the spraying flow field, the structure and position of the diffuser have an important influence on the cleaning performance. When the conical opening of the diffuser is small, the cleaning effect of the upper part of the filter cartridge is better, but there is a problem of low overall spraying intensity. When the conical opening of the diffuser is large, there is a problem of poor spraying uniformity, and it is difficult to take into account both the overall spraying intensity and the spraying uniformity. Summary of the invention

[0005] In view of the problems existing in the above-mentioned prior art, the present invention provides a filter cartridge dust collector, which can take into account both the overall blowing intensity and the blowing uniformity, thereby achieving higher cleaning efficiency and better cleaning effect.

[0006] To achieve the above object, the filter cartridge dust collector includes a plurality of filter cartridge units, each of which includes a vertically arranged filter cartridge and an induction nozzle assembly located directly above the filter cartridge, and the induction nozzle assembly includes a nozzle and a diffuser located directly below the nozzle;

[0007] The diffuser is an integrated, small-at-the-top, large-at-the-bottom teardrop-shaped structure, comprising a truncated cone structure portion at the top and a hemispherical structure portion at the bottom. The geometric center axis of the truncated cone structure portion passes through the center of the hemispherical structure portion, and a central guide hole that penetrates the diffuser in the axial direction is provided at the geometric center axis of the truncated cone structure portion.

[0008] As a further improvement of the present invention, a swirl generator is further provided directly below the nozzle.

[0009] As a further improvement of the present invention, the swirl cross-sectional area of ​​the swirl generator is not larger than the filter cartridge cross-sectional area of ​​the filter cartridge.

[0010] As an embodiment of the present invention, the filter cartridges of a plurality of filter cartridge units are arranged in sequence at set intervals to form a rectangular array.

[0011] As another embodiment of the present invention, the filter cartridges of a plurality of filter cartridge units are arranged in a set interval sequence to form a multi-row structure, and the filter cartridges of two adjacent rows are staggered to form a fork-shaped array.

[0012] Compared with the prior art, when the filter cartridge dust collector performs pulse cleaning operation, the presence of the diffuser with a water droplet-shaped structure that is small at the top and large at the bottom can play a good diversion and diffusion role on the jet airflow ejected through the nozzle, so that the airflow basin area is expanded, and under the action of the diffuser, the jet airflow has a good covering effect on the upper part of the filter cartridge, which can avoid the existence of a cleaning dead zone on the upper part of the filter cartridge. When the jet airflow passes through the diffuser, a part of the jet airflow flows out from the central guide hole and re-converges the airflow under the diffuser. Since the lower part of the diffuser is a hemispherical structure, there is no obvious tail vortex under the diffuser with a water droplet-shaped structure, and the airflow can move downward well along the diffuser. The setting of the central guide hole can not only avoid the negative pressure area at the lower part of the diffuser and hinder the mainstream, but also make the mainstream airflow converge downward faster and better, and the effect on the upper part of the filter cartridge is more obvious, which can better induce the airflow and avoid bottom turbulence, so that the mainstream airflow can move downward better, thereby reaching the upper part of the filter cartridge for spraying faster, thereby improving the cleaning efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic structural diagram of the filter cartridge unit of the present invention;

[0014] Figure 2 It is a schematic diagram of the structure of a traditional conical diffuser, wherein (Ⅰ) is a front view and (Ⅱ) is a top view of (Ⅰ);

[0015] Figure 3 is a schematic diagram of the structure of diffuser a, wherein (Ⅰ) is a front view and (Ⅱ) is a top view of (Ⅰ);

[0016] Figure 4 is a schematic diagram of the structure of diffuser b, wherein (Ⅰ) is a front view and (Ⅱ) is a top view of (Ⅰ);

[0017] Figure 5 is a schematic diagram of the structure of diffuser c, wherein (Ⅰ) is a front view and (Ⅱ) is a top view of (Ⅰ);

[0018] Figure 6 It is a schematic diagram of the installation position structure of the swirl generator of the present invention;

[0019] Figure 7 Schematic diagrams of different arrangements of multiple filter cartridge units of the present invention, wherein (I) is a schematic diagram of the structure when the filter cartridges are arranged in a straight line, and (II) is a schematic diagram of the structure when the filter cartridges are arranged in a staggered line;

[0020] Figure 8 It is a diagram showing the change of the maximum blowing airflow velocity on the filter cartridge wall with time when the blowing is carried out simultaneously under the conditions of the parallel filter cartridge working condition and the cross filter cartridge working condition;

[0021] Fig. 9It is a schematic diagram of the arrangement of pressure measuring points when the average pressure of the side wall is used as the evaluation index of the dust removal and cleaning performance of the filter cartridge in the test embodiment of the present invention;

[0022] Fig.10 It is a diagram showing the changes in average pressure at each measuring point of the four diffusers: original diffuser, diffuser b, diffuser a and diffuser c.

[0023] In the figure: 1, nozzle, 11, swirl generator, 2, diffuser, 21, central guide hole, 3, filter cartridge. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings.

[0025] The cartridge dust collector includes multiple cartridge units, such as Figure 1 As shown, each filter cartridge unit includes a vertically arranged filter cartridge 3 and an induction nozzle assembly located directly above the filter cartridge 3. The induction nozzle assembly includes a nozzle 1 and a diffuser 2 located directly below the nozzle 1. Figure 5 As shown, the diffuser 2 is an integrated structure, a teardrop-shaped structure that is small at the top and large at the bottom, including a truncated cone structure portion located at the top and a hemispherical structure portion located at the bottom. The geometric center axis of the truncated cone structure portion passes through the center of the hemispherical structure portion, and a central guide hole 21 that penetrates the diffuser 2 in the axial direction is provided at the geometric center axis of the truncated cone structure portion.

[0026] In order to verify the effectiveness of the water droplet-shaped diffuser 2 of the present invention in cleaning the filter cartridge, diffusers of other structures were selected for comparative tests. Figure 2 As shown, based on the traditional conical diffuser, a central guide hole is drilled at the axis position to form Figure 3 The diffuser a shown in the comparative test will be Figure 4The diffuser with a water droplet-shaped structure but without a central guide hole 21 is used as diffuser b for the comparative test, and the diffuser 2 with a water droplet-shaped structure and a central guide hole 21 is used as diffuser c for the comparative test. Models are constructed for the original traditional conical diffuser, diffuser a, diffuser b and diffuser c, and simulated spraying is performed. The simulation results show that the original diffuser and diffuser b are not equipped with central guide holes, so the lower parts of the original diffuser and diffuser b have different degrees of flow stagnation areas, lacking the convergence of the mainstream airflow and the induction effect on the surrounding airflow. However, diffusers a and diffusers c are equipped with central guide holes, and part of the sprayed airflow can be sprayed out from the central guide holes, which can not only avoid the negative pressure area in the lower part of the diffuser to hinder the mainstream, but also make the mainstream airflow converge faster and better downward. Compared with the original diffuser and diffuser b, diffusers a and diffuser c can reach a farther position on the upper part of the filter cartridge at the same time, and the effect on the upper part of the filter cartridge is more obvious. By comparing the original diffuser and diffuser b, and diffusers a and diffuser c, it can be seen that the water drop diffuser can better induce the airflow than the cone diffuser, while avoiding the bottom turbulence, so that the mainstream airflow can move downward better, so as to reach the upper part of the filter cartridge faster for spraying, and improve the cleaning efficiency. By zooming in on the velocity vector diagrams of the original diffuser, diffuser b, diffuser a and diffuser c around the simulated injection, it can be seen that the injected airflow slows down and stagnates on the surface of the diffuser after encountering the diffuser, while diffusers a and c with central guide holes have obvious re-convergence effect on the airflow at the bottom of the diffuser, and no obvious tail vortex appears at the bottom of the water droplet-shaped structure of diffusers b and diffuser c, and the airflow moves downward along the diffuser well. Judging only from the effect of the diffuser at the beginning, diffusers a and diffuser c with central guide holes are better than the original diffusers and diffuser b without central guide holes in inducing convergence of the surrounding airflow, while diffusers b and diffuser c with water droplet-shaped structures are better than the original diffusers and diffuser a with cone-shaped structures in airflow injection efficiency and effect on the upper part of the filter cartridge. At present, in the process of pulse jet dust removal and cleaning, the main indicators for evaluating the cleaning effect of the filter cartridge dust collector are the side wall pressure, the maximum reverse acceleration and the impulse density. The test example uses the average side wall pressure as the evaluation index of the filter cartridge dust removal and cleaning performance, such as Fig. 9 As shown in the figure, a measuring point is marked on the filter cartridge every 0.5m according to the distance from the top of the filter cartridge, and a total of 8 measuring points are marked. The average pressure of each measuring point of the original diffuser, diffuser b, diffuser a and diffuser c before the end of the injection is obtained by using the post-processing tool. Fig.10 As shown in the figure, by comparing the pressure changes at different positions of different diffusers, analyzing the change law of the average pressure along the radial side wall of the filter cartridge, the influence of the diffuser on the pressure of the filter cartridge side wall is obtained. Fig.10It can be seen that, as a whole, the pressure on the side wall of the filter cartridge is constantly rising as it moves downward along the filter cartridge, and the diffuser has an inductive effect on the airflow on the upper part of the filter cartridge, causing a negative pressure area to appear on the side wall of the upper part of the filter cartridge (measurement point 1). However, as the pulsed jet airflow gradually moves downward, the jet gas begins to expand continuously and converts the dynamic pressure into static pressure, so that the average pressure on the side wall of the bottom of the filter cartridge reaches the maximum value in the models of each diffuser. At the upper part of the filter cartridge, that is, at the positions of measurement points 1 and 2, the average pressure on the side wall of the filter cartridge of diffusers a and c with central guide holes is higher than the average pressure on the side wall of the original diffuser and diffuser b without central guide holes, which also confirms that diffusers a and c with central guide holes can make the jet airflow act better on the upper part of the filter cartridge. Similarly, the farther away from the top of the filter cartridge, the faster the average pressure on the filter cartridge side wall of the water droplet-shaped diffuser b and diffuser c models rises than the average pressure on the filter cartridge side wall of the cone-shaped original diffuser and diffuser a model. It can be seen that the water droplet-shaped diffusers b and diffuser c have better induction and convergence effects on the mainstream airflow than the cone diffuser, which can increase the effective volume of the sprayed gas to a certain extent and enable the sprayed gas to reach the lower part of the filter cartridge faster.

[0027] Therefore, when the filter cartridge dust collector is performing pulse cleaning, the presence of the diffuser 2 with a water droplet-shaped structure that is small at the top and large at the bottom can play a good role in diverting and diffusing the jet airflow ejected from the nozzle 1, so that the airflow flow area is expanded, and under the action of the diffuser 2, the jet airflow has a good covering effect on the upper part of the filter cartridge 3, which can avoid the existence of a cleaning dead zone on the upper part of the filter cartridge 3. Specifically: when the jet airflow passes through the diffuser 2, the flow rate slows down and it will stagnate on the surface of the diffuser 2. A part of the jet airflow flows out from the central guide hole 21 and re-converges the airflow under the diffuser 2. Since the lower part of the diffuser 2 is a hemispherical structure, there is no obvious tail vortex under the diffuser 2 with a water droplet-shaped structure, and the airflow can move downward along the diffuser 2 well. The setting of the central guide hole 21 can not only avoid the negative pressure area at the lower part of the diffuser 2 and hinder the mainstream, but also make the mainstream airflow converge downward faster and better, and the effect on the upper part of the filter cartridge 3 is more obvious. Compared with the traditional conical diffuser, the water drop-shaped diffuser 2 with a small top and a large bottom can better induce the airflow and avoid the bottom turbulence, so that the mainstream airflow can move downward better, so as to reach the lower part of the filter cartridge 3 for spraying faster, and improve the dust cleaning efficiency. The pulse cleaning operation can adopt the intermittent spraying method to prevent the high-speed airflow from carrying dust and escaping with the wind, which is beneficial to dust sedimentation and improves the dust cleaning efficiency. By controlling the spraying time interval and adjusting the interval of the entire vein, the pressure drop of the entire equipment can be operated in a basically stable state, and the interval of the vein can be extended as much as possible without affecting the normal operation. This not only reduces the damage of the pulse valve diaphragm, but also reduces the consumption of compressed air, so that the use can better extend the service life of the equipment.

[0028] In order to achieve a better dust cleaning effect, as a further improvement of the present invention, a swirl generator 11 is further provided directly below the nozzle 1. When the nozzle airflow passes through the swirl generator 11, it rotates and forms a rotating jet after being ejected from the nozzle. Figure 6 As shown, the swirling jet is used to entrain the surrounding airflow, so that the jet cross-section is continuously increased until it enters the interior of the filter 3 and gradually develops downward, which can form a swirling area that is beneficial to acting on a larger cleaning wall surface, and make the spraying airflow and the surrounding airflow strongly mixed, while also avoiding the impact of the unidirectional jet on the bottom of the filter cartridge. In order to ensure that the swirling jet enters the filter cartridge 3 smoothly, the swirling transverse size and its development can be controlled so that the swirling cross-sectional area is ≤ the filter cartridge cross-sectional area, so that the swirling jet can smoothly enter the filter cartridge 3 when it moves downward to the upper end of the filter cartridge 3.

[0029] Different arrangements of the filter cartridges 3 in the multiple filter cartridge units have an impact on the cleaning effect, such as Figure 7The figures are in-line and in-cross. In-line means that the filter cartridges 3 of multiple filter cartridge units are arranged in a set interval sequence in the airflow direction to form a rectangular array. In-cross means that the filter cartridges 3 of multiple filter cartridge units are arranged in a set interval sequence in the airflow direction to form a multi-column structure, and the filter cartridges 3 of two adjacent columns are staggered to form a forked array. Under the same test conditions, the in-line spray cleaning test and the in-cross spray cleaning test were carried out respectively. The maximum spray airflow velocity on the wall of the filter cartridge 3 changes with time as shown in the figure. Figure 8 As shown, when the spraying just starts at t=0.02s, the maximum air flow velocity on the wall of the longitudinal filter cartridge 3 is about 179.88m / s, and the maximum air flow velocity on the wall of the cross-pair filter cartridge 3 is about 63.82m / s. The maximum air flow velocity on the wall of the longitudinal filter cartridge 3 is much higher than that of the cross-pair filter cartridge 3. As the spraying continues, the maximum air flow velocity on the wall of the longitudinal filter cartridge 3 decreases rapidly; at t=0.03s, it decreases to 27.64m / s. On the contrary, the maximum air flow velocity on the wall of the cross-pair filter cartridge 3 increases to 82.46m / s, exceeding the longitudinal filter cartridge 3; thereafter, as the spraying continues, the maximum air flow velocity on the wall of the longitudinal filter cartridge 3 first decreases and then increases, and is about 20.53m / s and 36.6m / s at t=0.05s and t=0.2s respectively; the maximum air flow velocity on the wall of the cross-pair filter cartridge 3 gradually decreases, and is about 21.9m / s at t=0.2s. It can be seen from this that: the cleaning effect of the dust particles at the bottom of the filter cartridge 3 when the filter cartridges 3 are arranged in sequence and sprayed at the same time is better than that when the filter cartridges 3 are arranged in a cross-sequence, but the cleaning effect of the dust particles in the middle and upper part of the filter cartridge 3 when the filter cartridges 3 are arranged in a cross-sequence and sprayed at the same time is significant, especially the medium and large dust particles with a diameter of 20-60μm.

Claims

1. A filter cartridge dust collector, comprising a plurality of filter cartridge units, each filter cartridge unit comprising a vertically arranged filter cartridge (3) and an induction nozzle assembly located directly above the filter cartridge (3), the induction nozzle assembly comprising a nozzle (1) and a diffuser (2) located directly below the nozzle (1); It is characterized in that The diffuser (2) is an integrated structure, a water drop-shaped structure that is small at the top and large at the bottom, and comprises a truncated cone structure portion located at the top and a hemispherical structure portion located at the bottom. The geometric center axis of the truncated cone structure portion passes through the center of the hemispherical structure portion, and a central guide hole (21) that penetrates the diffuser (2) in the axial direction is provided at the position of the geometric center axis of the truncated cone structure portion.

2. The cartridge dust collector according to claim 1, characterized in that: A swirl generator (11) is also provided directly below the nozzle (1).

3. The cartridge dust collector according to claim 2, characterized in that: The cyclone cross-sectional area of ​​the cyclone generator (11) is not greater than the filter cartridge cross-sectional area of ​​the filter cartridge (3).

4. The cartridge dust collector according to claim 1, characterized in that: The filter cartridges (3) of the plurality of filter cartridge units are arranged in sequence according to a set interval to form a rectangular array.

5. The cartridge dust collector according to claim 1, characterized in that: The filter cartridges (3) of the plurality of filter cartridge units are arranged in a set interval sequence to form a multi-row structure, and the filter cartridges (3) of two adjacent rows are staggered to form a fork-shaped array.

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