A cloth bag dust removal and vibration cleaning device suitable for a boiling dryer and a cleaning method thereof

Abstract

This invention discloses a bag filter dust removal device and method suitable for fluidized bed dryers, comprising a fluidized bed and a bag filter dust removal system. The bag filter dust removal system consists of a support frame, filter bags, and a vibration device. The support frame adopts a double-layer cage structure, and the filter bags include an inner and an outer filter bag, forming a double-layer filtration system to improve dust collection efficiency. The vibration device consists of a vibrator, a flexible belt, and vibrating plates. The vibrator is mounted on a rod via the flexible belt and drives the vibrating plates to act on the filter bags for high-frequency vibration cleaning. The flexible belt can mitigate the vibration impact on the frame and reduce noise. The start / stop of the vibrator and the magnitude of the vibration force are controlled according to the airflow pressure difference before and after the filter bags, achieving on-demand cleaning. This invention removes dust from the surface of the filter bags through vibration cleaning, reduces airflow resistance, stabilizes the fluidization effect, extends the filter bag life, and reduces energy consumption. It is suitable for drying powdery or granular materials in various industries.

Description

Technical Field

[0001] This invention belongs to the field of bag filter dust removal technology for material drying, and relates to the optimized design of dust removal system for fluidized bed dryers. Specifically, it is a bag filter dust removal device and its dust removal method suitable for fluidized bed dryers, which can efficiently capture and remove fine dust generated during fluidized bed drying. It is applicable to the drying and dust removal of solid preparations or materials in the pharmaceutical, food and chemical industries. Background Technology

[0002] Fluidized bed drying technology, as a highly efficient, uniform, and rapid drying method, is widely used in the pharmaceutical, food, and chemical industries. Its principle is to fluidize granular or powdery materials using a high-speed airflow, increasing the contact area between the material and the hot air, thereby improving heat and mass transfer efficiency and achieving rapid drying. However, during fluidized bed drying, the interaction between the material and the airflow generates a large amount of fine dust. These fine particles easily escape with the airflow, causing not only material loss but also environmental pollution. Therefore, an efficient dust removal system is an indispensable component of fluidized bed drying equipment.

[0003] Currently, dust removal technologies applied to fluidized bed dryers mainly include baghouse dust collection, cyclone dust collection, wet scrubbing, and electrostatic precipitators. Among these, baghouse dust collection technology has become one of the most widely used dust removal methods due to its high dust collection efficiency, simple structure, and stable operation. Baghouse dust collectors utilize filter bags made of woven fabric to capture dust particles in the airflow, allowing clean gas to pass through, thereby achieving gas-solid separation. The cleaning method of baghouse dust collectors is one of the key factors affecting their performance; existing fluidized bed dryers generally employ mechanical shaking cleaning or pulse jet cleaning methods for baghouse dust collection.

[0004] The filter bags in the mechanical shaking cleaning method are located in the upper part of the fluidization chamber, divided into left and right chambers, which alternately and intermittently shake for cleaning. When fine powder is captured by the filter bags to a certain extent, the left exhaust valve is closed, and the filter bags in the left chamber shake up and down under the action of a cylinder, causing the shaken-off powder to fall back into the fluidized bed for further drying. After the operation is complete, the left exhaust valve is opened and the right exhaust valve is closed, and the filter bags in the right chamber are shaken again. The left and right chambers alternate shaking in this cycle to clean the captured powder and keep the filter bags unobstructed. However, the disadvantages of the shaking cleaning method are: incomplete cleaning, unstable airflow resistance in the filter bags causing airflow velocity pulsation in the fluidization chamber, affecting the fluidization effect, and the filter bags are easily damaged, have a short lifespan, and high energy consumption.

[0005] Pulse-jet cleaning involves placing high-pressure gas nozzles above the filter bags. When fine powder is captured by the bags to a certain extent, the nozzle valves are opened to clean the bags one by one or simultaneously using counter-current airflow. Compared to shaking cleaning, pulse-jet cleaning has advantages such as relatively better cleaning effect and higher degree of automation. However, pulse-jet cleaning also has some drawbacks: the airflow resistance of the filter bags is unstable, and the instantaneous airflow impact generated by the jet gas can easily cause severe interference to the flow field inside the fluidization chamber, affecting the fluidization effect. In addition, the high-pressure gas jet device has high energy consumption. Furthermore, the direct impact of high-pressure gas on the filter bags can easily cause fatigue damage to the filter bags with long-term use, reducing their service life.

[0006] Taking the dust removal equipment for a fluidized bed dryer with dust collection and compression function disclosed in utility model patent CN209181399U as an example, although it improves the dust collection and compression effect through the design of rotating inner shell and extrusion plate, its dust removal process still relies on mechanical rotation and extrusion, failing to effectively solve the problems of incomplete bag cleaning and airflow interference. CN208952537U discloses a dust removal device for a fluidized bed dryer that is easy to clean, which adopts a multi-stage filtration and back-blowing structure. Although it is easy to clean, the back-blowing airflow disturbs the fluidized bed and does not improve the bag cleaning mechanism, still facing the defects of low cleaning efficiency and resistance fluctuations.

[0007] In summary, existing baghouse dust collection technology for fluidized bed dryers still has many problems in terms of dust removal efficiency, airflow stability, bag life, and energy consumption. Therefore, how to improve dust removal efficiency, stabilize airflow, extend bag life, and reduce energy consumption are urgent technical problems to be solved in fluidized bed drying and related fields. Summary of the Invention

[0008] (a) Purpose of the invention

[0009] To address the aforementioned deficiencies and shortcomings of existing technologies, the present invention aims to solve the problems of incomplete dust removal, unstable airflow resistance in the bags, airflow velocity pulsation in the fluidization chamber, poor fluidization effect, high energy consumption, and easy damage and short lifespan of the bags during shaking dust removal. The invention provides a bag filter dust removal device and method suitable for fluidized bed dryers, which optimizes the coupling between the bag cleaning dynamics mechanism and the system structure to achieve coordinated control of dust removal and fluidized bed operation. Specifically, the invention uses a vibrator to generate vibration, which drives vibrating plates to strike the surface of the bags, removing fine powder adhering to them, reducing dust accumulation time, lowering airflow resistance, ensuring uniform airflow velocity in the fluidization chamber, and improving fluidization effect. Simultaneously, the flexible belt design of the vibrator can mitigate frame vibration and noise, extend bag lifespan, and reduce equipment energy consumption. Furthermore, the excitation force of the vibrator can be flexibly adjusted according to dust conditions and automatically controlled by the pressure difference across the bags, further optimizing dust removal efficiency and energy consumption control.

[0010] (II) Technical Solution

[0011] To achieve the objective of this invention and solve its technical problems, the present invention adopts the following technical solution:

[0012] The first objective of this invention is to provide a bag filter dust collection and vibration cleaning device suitable for fluidized bed dryers, used for fluidized bed drying of solid particles or powdery materials and for dust collection and removal, comprising:

[0013] A fluidized bed is used to support and agitate materials into a fluidized state under the action of airflow.

[0014] A baghouse dust collector vibration cleaning system, installed at the top of a fluidized bed, is used to collect dust from the airflow discharged from the fluidized bed and keep the filter bags unobstructed by vibration cleaning. It includes at least a bag cage, filter bags, and a vibration device, wherein:

[0015] The bag frame is a cage-like structure and is coaxially installed in the top cylinder of the fluidized bed. It includes an annular top plate and inner and outer double-layer cages. The outer edge of the annular top plate is sealed and fixed to the side wall of the top cylinder of the fluidized bed. The inner and outer double-layer cages are fixed on the bottom surface of the annular top plate, and several axially extending inserts are distributed in the radial space between the inner and outer cages.

[0016] The filter bag includes an inner filter bag and an outer filter bag, which are used to capture dust carried by the airflow in the fluidized bed. The inner filter bag is attached to and fixed to the inner side of the inner cage, and the outer filter bag covers and is fixed to the outer side of the outer cage, forming a double-layer filter structure.

[0017] The vibration device comprises several units distributed circumferentially to apply vibration to the filter bag to remove dust adhering to its surface. Each vibration device includes a vibrator, a flexible belt, and a vibrating plate. Each vibrator is mounted on a rod between the inner and outer double-layer cages via flexible belts on its left and right sides to reduce the vibration impact on the filter bag frame and reduce noise. A vibrating plate is fixedly connected to its inner and outer sides respectively. Both the inner and outer vibrating plates have a perforated plate structure extending axially to maintain the airflow area and reduce airflow resistance fluctuations during dust removal. The vibration force generated by the vibrator is transmitted to the inner and outer filter bag surfaces through the inner and outer vibrating plates to remove dust. The start / stop and the magnitude of the vibration force are adjusted according to the airflow pressure difference before and after the filter bag.

[0018] The second objective of this invention is to provide a dust removal method for the above-mentioned bag filter vibrating cleaning device suitable for a fluidized bed dryer, which mainly includes the following steps in its implementation:

[0019] SS1. Start the fluidized bed drying process: Start the fluidized bed to make the solid particles or powdered materials agitate and boil into a fluidized state, while the airflow carries the dust into the bag filter dust removal system.

[0020] SS2. Dust cleaning start condition judgment: Obtain the airflow pressure difference data before and after the filter bag, and judge whether the filter bag has reached the state that needs to be cleaned based on the preset pressure difference threshold. If the pressure difference value exceeds the set threshold, the dust cleaning operation is initiated. If the dust cleaning condition is not met, the airflow pressure difference is monitored.

[0021] SS3. Start-up of the excitation device: When the air pressure difference between the front and rear of the filter bag reaches the set dust removal threshold, a start command is sent to the excitation device. The exciters start sequentially or simultaneously according to the preset order and adjust the excitation force and excitation frequency parameters of the exciters according to the size of the air pressure difference between the front and rear of the filter bag. The vibrating plate is driven to vibrate and impact the inner and outer filter bags, so that the dust attached to the surface of the filter bags is removed.

[0022] SS4. Dust cleaning completion judgment: Real-time monitoring of the airflow pressure difference before and after the filter bag. If the pressure difference is detected to return to the set normal operating range, a control command is issued to stop the excitation device and terminate the current dust cleaning operation. If the pressure difference is not restored, the excitation dust cleaning continues until the set conditions are met.

[0023] SS5. Multiple cleaning cycles: If the pressure difference before and after the filter bag does not return to the normal range within the set maximum cleaning time, adjust the vibration frequency and amplitude of the excitation device and perform the cleaning cycle again until the airflow of the filter bag returns to normal.

[0024] SS6. Dust Cleaning Status Reset and Monitoring: After dust cleaning is completed, reset the excitation device to standby mode and continue to monitor the airflow pressure difference before and after the filter bag. When the pressure difference exceeds the threshold again, repeat the dust cleaning steps to ensure that the filter bag maintains a low resistance, high air permeability and effective dust cleaning working state for a long time.

[0025] (III) Technical Effects

[0026] Compared with the prior art, the bag filter dust collector vibration cleaning device and its cleaning method for fluidized bed dryers of the present invention have the following beneficial and significant technical effects:

[0027] (1) The present invention replaces the traditional shaking and pulse jet cleaning methods with a vibration cleaning device, which significantly improves the cleaning effect. The vibrator in the vibration device generates vibration, and the vibrating plate beats the surface of the filter bag, which can thoroughly remove the dust attached to the filter bag, reduce the accumulation time of dust on the surface of the filter bag, ensure the stability of the airflow resistance of the filter bag, avoid the fluctuation of airflow resistance caused by incomplete cleaning, thereby improving the uniformity of airflow velocity in the fluidized bed and optimizing the fluidization effect.

[0028] (2) The bag and frame structure in the bag dust removal vibration cleaning system of the present invention can increase the dust removal area, reduce the airflow resistance of the bag, and improve the dust removal efficiency; the inner bag and the outer bag are respectively attached to the inner cage and the outer cage of the bag frame to form a double-layer filter barrier, which can more effectively capture dust in the airflow and reduce dust escape. At the same time, the double-layer filter structure increases the filter area, reduces the load of the single-layer bag, and extends the service life of the bag.

[0029] (3) The present invention employs a vibratory cleaning device, which makes bag cleaning simple and easy to control, and cleaning more thorough. The airflow resistance of the bag is smaller and more stable, the service life of the bag is longer, the airflow velocity in the fluidization chamber is more uniform, the fluidization effect is better, and the dust removal energy consumption is reduced. Furthermore, the present invention monitors the airflow pressure difference before and after the bag and adjusts the start and stop of the vibrator and the magnitude of the vibration force according to the pressure difference change, ensuring timely and accurate cleaning operation.

[0030] (4) The vibrating plate of the present invention adopts an axially extending perforated plate structure, which can maintain a large airflow area during the dust removal process and avoid flow field disturbance caused by the vibrating plate blocking the airflow. In addition, the present invention avoids the problem of excessive impact force caused by direct rigid connection by using a flexible belt to suspend the vibrator, and effectively reduces the structural damage to the filter bag and filter bag frame during vibration transmission.

[0031] (5) This invention is applicable to the drying of various materials, including the drying of materials in the solid dosage form pharmaceutical process (fluidized bed dryer and fluidized bed granulator), and can also be applied in the food and chemical industries. By adjusting the excitation force and vibration frequency of the vibrator, it can adapt to the dust characteristics and dust removal requirements of different materials, ensuring the efficient operation of the equipment under different working conditions. Attached Figure Description

[0032] Figure 1 This is a diagram of the bag filter dust collection and vibration cleaning device for a fluidized bed dryer according to the present invention;

[0033] Figure 2 This is a schematic diagram of the bag filter vibration cleaning system in this invention;

[0034] Figure 3 for Figure 2 A magnified view of a local area I in the middle;

[0035] Figure 4 for Figure 2 AA section view;

[0036] Figure 5 This is a three-dimensional structural schematic diagram of the excitation device in this invention;

[0037] Figure 6 This is a three-dimensional structural diagram of the bag frame in this invention;

[0038] Figure 7 This is a top view of the bag frame in this invention;

[0039] Explanation of reference numerals in the attached figures:

[0040] 100-Air inlet treatment system, 200-Fluidized bed, 210-Lower cylinder, 220-Sealing gasket, 230-Upper cylinder, 300-Bag dust collector vibration cleaning system, 310-Bag, 311-Inner bag, 312-Outer bag, 313-Central bag, 320-Vibration device, 321-Vibrating plate, 322-Connecting plate, 323-Vibrator, 324-Flexible belt, 330-Bag frame, 331-Annular top plate, 332-Inner cage, 333-Outer cage, 334-Insert rod, 335-Central cage, 340-Sealing ring, 350-Clamping clamp, 400-Exhaust duct, 500-Exhaust fan. Detailed Implementation

[0041] This invention aims to provide a bag filter dust collector with vibration cleaning device and cleaning method suitable for fluidized bed dryers. To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be described in more detail below with reference to the accompanying drawings. The described embodiments are some, but not all, embodiments of this invention, and are exemplary and intended to explain this invention, and should not be construed as limiting this invention.

[0042] Example 1: Baghouse dust collector vibration cleaning device suitable for fluidized bed dryers

[0043] As a specific embodiment, the bag filter dust collector vibration cleaning device suitable for fluidized bed dryers provided in this embodiment of the invention, such as... Figure 1As shown, this system is used for fluidized bed drying of solid particles or powders and for dust collection and removal. Its main components include an air inlet treatment system 100, a fluidized bed 200, a bag filter vibration cleaning system 300, an exhaust duct 400, and an exhaust fan 500. The air inlet treatment system 100 is connected to the bottom air inlet of the fluidized bed 200 and is used to supply treated gas to the fluidized bed 200. The bag filter vibration cleaning system 300 is located at the top of the fluidized bed 200 and is used to collect dust from the exhaust airflow from the fluidized bed 200 and keep the filter bags unobstructed through vibration cleaning. One end of the exhaust duct 400 is connected to the air outlet at the top of the bag filter vibration cleaning system 300, and the other end is connected to the exhaust fan 500. The exhaust fan 500 is used to generate negative pressure. The suction effect causes the airflow to be drawn in by the negative pressure of the induced draft fan 500, and then enters the fluidized bed 200 through the air intake treatment system 100. The powder or granular medicine powder is agitated and boiled into a fluidized state. The air flows through the bag filter dust removal and vibration system 300, where a portion of the fine powder is captured by the filter bag 310. The vibrator 323 in the vibration device 320 generates vibration, which drives the vibrating plate 321 to vibrate and remove the fine powder from the filter bag 310. The filtered air is then drawn out by the induced draft fan 500 through the induced draft duct 400.

[0044] like Figure 2 and Figure 3 As shown, the bag filter dust collection and vibration cleaning system 300 of the present invention is installed at the top of the fluidized bed 200, including a bag frame 330, a bag 310, and a vibration device 320. The bag frame 330 is a cage-like structure and is coaxially installed in the top cylinder of the fluidized bed 200, including an annular top plate 331 and inner and outer double-layer cages, wherein: the outer edge of the annular top plate 331 is sealed and fixed to the side wall of the top cylinder of the fluidized bed 200; the inner and outer double-layer cages are fixedly installed on the bottom surface of the annular top plate 331, and a plurality of axially extending insert rods 334 are distributed circumferentially in the radial space between the inner cage 332 and the outer cage 333. The filter bag 310 includes an inner filter bag 311 and an outer filter bag 312, used to collect dust carried by the airflow in the fluidized bed. The inner filter bag 311 is attached to and fixed to the inner side of the inner cage 332, and the outer filter bag 312 covers and is fixed to the outer side of the outer cage 333, forming a double-layer filtration structure. Several vibration devices 320 are provided and distributed circumferentially to apply vibration to the filter bags 310 to remove dust adhering to their surfaces.

[0045] More specifically, the top cylinder of the fluidized bed 200 includes a lower cylinder 210, an upper cylinder 230, and a sealing gasket 220 located at the connection between the two; the annular top plate 331 of the bag filter 330 is fixedly connected to the upper cylinder 230 and the lower cylinder 210 by flange bolts, and the lower surface of the annular top plate 331 is tightly fitted with the sealing gasket 220 to form a sealing structure, ensuring that all airflow is filtered through the bag filter 310 before being discharged from the fluidized bed 200.

[0046] like Figure 6 , 7 As shown in the embodiment of the present invention, the inner cage 332 and the outer cage 333 of the bag frame 330 are both composed of multiple support rods extending axially and arranged circumferentially and multiple annular support rings distributed circumferentially to form a cage-like support structure. The spacing between the support rods and the annular support rings is set according to the material and material characteristics of the bag 310 to ensure that the bag 310 will not collapse or deform under the negative pressure of the airflow, while ensuring that the bag 310 has sufficient strength to withstand the vibration of the excitation device 320.

[0047] Furthermore, preferably, the bag frame 330 is provided with a central cage 335 located at its center. The central cage 335 covers and fixes the central bag 313 on its outside. The central cage 335 is provided with at least one excitation device 320, whose vibrating plate 321 is used to transmit the excitation force generated by the vibrator 323 to the surface of the central bag 313 to remove dust.

[0048] A sealing ring 340 and a clamp 350 are provided between the top of the inner filter bag 311 and the inner cage 332, and between the top of the outer filter bag 312 and the outer cage 333. The clamp 350 is used to fasten the filter bag 310 to the filter bag frame 330 to prevent the filter bag 310 from falling off or shifting under the action of airflow and vibration. The sealing ring 340 is used to ensure that the airflow does not leak from the connection between the filter bag 310 and the filter bag frame 330, to ensure that the filter bag 310 maintains a stable and reliable filtration effect during long-term use, and at the same time facilitates the installation, replacement and maintenance of the filter bag 310. Preferably, both the inner bag 311 and the outer bag 312 are made of filter material that is resistant to high temperature, wear, and has good air permeability. The fiber diameter is 10-20 micrometers, the porosity is 70%-85%, and the filtration accuracy is 1-10 micrometers. The surface is treated with antistatic and anti-adhesion agents. The material is selected from polyester, polypropylene, polyamide, glass fiber, or polytetrafluoroethylene according to the characteristics of the material being treated, so as to adapt to different process conditions and material characteristics. Among them, the filtration accuracy of the inner bag 311 is greater than that of the outer bag 312, so as to ensure that the inner and outer bags form a gradient filtration structure. This allows the outer bag 312 to capture larger dust particles, while the inner bag 311 is used to capture fine dust particles, thereby improving the overall dust removal efficiency and reducing the frequency of bag cleaning.

[0049] like Figure 4 and Figure 5As shown, the number of vibration devices 320 in this invention is 4-12, evenly distributed along the circumference of the bag frame 330, with the included angle between adjacent vibration devices 320 ranging from 30° to 90°. Each vibration device 320 mainly consists of a vibrating plate 321, a connecting plate 322, a vibrator 323, and a flexible belt 324. Each vibrator 323 is installed and fixed to the insert rod 334 between the inner and outer double-layer cages of the bag frame 330 through through holes on the sides of the flexible belt 324 on its left and right sides. The flexible belt 324, due to its flexibility, can reduce or avoid vibration and noise caused by the frame. Furthermore, a vibrating plate 321 is fixedly connected to the inner and outer sides of the vibrator 323 through a connecting plate 322. The excitation force generated by the vibrator 323 is transmitted to the inner and outer bag surfaces through the inner and outer vibrating plates 321 to remove dust. In addition, the vibration phase difference of the vibrators 323 of adjacent excitation devices 320 is 90°-180° and different axial installation heights are set to avoid resonance superposition. Each vibrator 323 is independently controlled to start and stop and excitation force, so as to achieve dust removal in different areas and time periods, avoid large fluctuations in airflow in the fluidized bed 200 caused by simultaneous dust removal, and ensure the stability of fluidized drying.

[0050] More specifically, the vibrator 323 can be inertial, electric, or electromagnetic. The vibrator 323 generates vibration and transmits it through its output shaft and connecting plate 322 to the vibrating plate 321. The excitation force is perpendicular to the surface of the filter bag 310. The vibration of the vibrating plate 321 beats the surface of the filter bag 310, thus removing dust from the filter bag 310. The start / stop of the vibrator 323, as well as the excitation frequency and amplitude, are dynamically adjusted based on the characteristics of the material dust and real-time monitoring data of the pressure difference across the filter bag 310. When the pressure difference reaches a preset threshold, vibration cleaning is initiated. The greater the pressure difference, the greater the corresponding excitation frequency and amplitude. Vibration stops when the pressure difference drops to the normal range. This adapts to the cleaning needs under different material characteristics and dust load conditions, extending the service life of the filter bag 310 and reducing energy consumption and operating noise. The excitation force of the vibrator 323 can be adjusted according to the dust conditions of the material to increase or decrease the vibration amplitude. The start and stop of the vibrator 323 can be controlled by the pressure difference before and after the filter bag 310.

[0051] In this embodiment of the invention, the vibrating plate 321 is disposed on the inner and outer sides of the vibrator 323 via the connecting plate 322, and its plate surface is designed as a perforated plate. The size and distribution of its pores are optimized according to the airflow velocity and dust particle size, with a mesh rate of not less than 50% to prevent airflow blockage, reduce the flow area, and avoid dust accumulation on the surface of the vibrating plate 321. The vibrating plate 321 is preferably made of an elastic metal material, and its surface curvature and hardness are adapted to the filter bag 310 to avoid damage to the filter bag 310 during vibration, while simultaneously meeting the requirements of airflow and vibration transmission. The gap between the vibrating plate 321 and the filter bag 310 is preferably adjustable, and the gap size can be adjusted to adapt to the dust characteristics and dust removal requirements of different materials, ensuring the dust removal effect while preventing the filter bag 310 from being damaged due to excessive friction.

[0052] Preferably, the flexible belt 324 is made of rubber or engineering plastic with good elasticity and fatigue resistance. Its elastic parameters are optimized and designed with a thickness of 3-8 mm and a width of 30-50 mm to ensure effective absorption of vibration impact from the vibrator 323 during long-term use, reduce vibration damage to the support frame 330, and reduce the noise level during equipment operation. Both ends of the flexible belt 324 are fixedly connected to the vibrator 323 and the insertion rod 334, respectively.

[0053] Preferably, the bag filter dust collector vibration cleaning system 300 is also equipped with a differential pressure detection device and a control system. The differential pressure detection device monitors the pressure difference changes on both sides of the filter bag 310 in real time and transmits the data to the control system. The control system controls the start / stop and vibration parameters of the vibrator 323 according to a preset differential pressure threshold. When the detected differential pressure exceeds the upper threshold, vibration cleaning is started; when the differential pressure drops to the lower threshold, vibration is stopped, thus controlling the bag cleaning process, improving equipment operating efficiency and reducing energy consumption. The control system sets the cycle, duration, and intensity of vibration cleaning according to drying process requirements and material characteristics, and adjusts the frequency and magnitude of vibration cleaning according to the pressure difference change trend on both sides of the filter bag 310, ensuring cleaning effect and extending the service life of the filter bag 310. The excitation frequency of the vibrator 323 is 10-60Hz, and the excitation force ranges from 50-500N. The pressure difference monitoring threshold before and after the filter bag 310 is set to 200-1000Pa. When the pressure difference exceeds the set threshold, the control system first starts some of the excitation devices 320 for dust removal. If the pressure difference does not drop to the normal range, the number of excitation devices 320 started and the excitation force are gradually increased until the dust removal operation of all filter bags 310 is completed, so as to realize adaptive graded dust removal control, so as to ensure the dust removal effect and reduce the interference to the fluidization process.

[0054] The working principle of the bag filter vibrating cleaning device for fluidized bed dryers of the present invention is as follows: Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the filter bag 310 captures fine powder in the airflow of the fluidized bed 200. The vibrator 323 in the excitation device 320 generates vibration, which drives the vibrating plate 321 to vibrate and beat the filter bag 310, removing the fine powder on the filter bag 310. This reduces the residence time of fine powder on the filter bag 310, reduces the airflow resistance of the filter bag 310, improves the dust removal efficiency, and reduces energy consumption.

[0055] Example 2: Dust Removal Method

[0056] In the bag filter vibrating cleaning device for fluidized bed dryers provided in Embodiment 1 above, Embodiment 2 further elaborates on the cleaning method based on this device, which mainly includes the following in its implementation:

[0057] SS1. Start the fluidized bed drying process: Start the fluidized bed 200 to make the solid particles or powdered materials agitate and boil into a fluidized state, while the airflow carries the dust into the bag filter dust removal system 300.

[0058] SS2. Dust cleaning start condition judgment: Obtain the airflow pressure difference data before and after the filter bag 310, and judge whether the filter bag 310 has reached the state that needs to be cleaned based on the preset pressure difference threshold. If the pressure difference value exceeds the set threshold, the dust cleaning operation is initiated. If the dust cleaning condition is not met, the airflow pressure difference is monitored.

[0059] SS3. Start-up of the vibration excitation device:

[0060] When the airflow pressure difference between the front and rear of the filter bag 310 reaches the set dust removal threshold, a start command is sent to the vibration device 320. The vibrator 323 starts sequentially or simultaneously according to a preset order and adjusts the excitation force and excitation frequency parameters of the vibrator 323 according to the size of the pressure difference between the front and rear of the filter bag. The vibrating plate 321 is driven to vibrate and impact the inner filter bag 311 and the outer filter bag 312, so that the dust attached to the surface of the filter bag is removed.

[0061] SS4. Dust removal completion judgment: Real-time monitoring of the airflow pressure difference before and after the filter bag 310. If the pressure difference is detected to return to the set normal operating range, a control command is issued to stop the excitation device 320 and terminate the current dust removal operation. If the pressure difference is not restored, the excitation dust removal continues until the set conditions are met.

[0062] SS5. Multiple cleaning cycles: If the pressure difference before and after the filter bag 310 does not return to the normal range within the set maximum cleaning time, adjust the vibration frequency and amplitude of the excitation device 320 and perform the cleaning cycle again until the airflow of the filter bag 310 returns to normal.

[0063] SS6. Dust Removal Status Reset and Monitoring:

[0064] After the dust removal is completed, the vibration device 320 is reset to standby mode, and the airflow pressure difference before and after the filter bag 310 is monitored. When the pressure difference exceeds the threshold again, the dust removal step is repeated to ensure that the filter bag 310 maintains a low resistance, high air permeability and effective dust removal working state for a long time.

[0065] In summary, the bag filter dust removal device for fluidized bed dryers of the present invention significantly improves the dust removal effect, reduces energy consumption, extends equipment service life, and optimizes fluidization effect through innovative dust removal methods, optimized structural design and control technology, and has important industrial application value and economic benefits.

[0066] The objectives of this invention have been fully and effectively achieved through the above embodiments. Those skilled in the art will understand that this invention includes, but is not limited to, the contents described in the accompanying drawings and the specific embodiments described above. Although the invention has been described with reference to what is currently considered the most practical and preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments, and any modifications that do not depart from the functional and structural principles of the invention will be included within the scope of the claims.

Claims

1. A bag filter dust collector vibration cleaning device suitable for fluidized bed dryers, characterized in that, include: Fluidized bed; A baghouse dust collector vibration cleaning system includes at least a bag cage, a bag, and a vibration device, wherein: The bag frame is a cage-like structure and is coaxially installed in the top cylinder of the fluidized bed. It includes an annular top plate and inner and outer double-layer cages. The outer edge of the annular top plate is sealed and fixed to the side wall of the top cylinder of the fluidized bed. The inner and outer double-layer cages are fixed on the bottom surface of the annular top plate, and several axially extending inserts are distributed in the radial space between the inner and outer cages. The filter bag includes an inner filter bag and an outer filter bag, wherein: the inner filter bag is attached to and fixed to the inside of the inner cage, and the outer filter bag is covered and fixed to the outside of the outer cage. The filtration accuracy of the inner filter bag is greater than that of the outer filter bag. The outer filter bag is used to capture larger dust particles, and the inner filter bag is used to capture fine dust particles. A gradient filtration structure is formed between the inner and outer filter bags. The vibration device is provided in several parts and distributed circumferentially. Each vibration device includes a vibrator, a flexible belt and a vibrating plate. Each vibrator is installed on the insert rod between the inner and outer double-layer cages through the flexible belts on its left and right sides. A vibrating plate is fixedly connected to its inner and outer sides respectively. Both the inner and outer vibrating plates are perforated plate structures extending axially. They are made of elastic metal material, and their surface curvature and hardness are adapted to the cloth bag. The mesh rate is not less than 50%. A vibrating plate is fixedly connected to the inner and outer sides of the vibrator through a connecting plate. The direction of the vibration force is perpendicular to the surface of the cloth bag. The vibration force generated by the vibrator is transmitted to the surface of the inner and outer cloth bags through the inner and outer vibrating plates to remove dust. Its start and stop and the vibration force are adjusted according to the airflow pressure difference before and after the cloth bag. The circumferential angle between adjacent excitation devices ranges from 30° to 90°. The vibration phase difference between the exciters of adjacent excitation devices is 90° to 180°, and different axial installation heights are set to avoid resonance superposition. Each exciter is independently controlled to start / stop and excitation force to achieve zoned and time-segmented dust removal. The start / stop of the exciter, as well as the excitation frequency and amplitude, are dynamically adjusted based on the material dust characteristics and real-time monitoring data of the pressure difference before and after the filter bag. When the pressure difference reaches the upper threshold, excitation dust removal is started. The greater the pressure difference, the greater the corresponding excitation frequency and amplitude. When the pressure difference drops to the lower threshold, excitation stops. If the pressure difference before and after the filter bag does not return to the normal range within the set maximum dust removal time, the vibration frequency and amplitude of the excitation device are adjusted until the airflow of the filter bag returns to normal.

2. The bag filter dust collection and vibration cleaning device suitable for fluidized bed dryers according to claim 1, characterized in that, It also includes an air intake treatment system, an exhaust duct, and an exhaust fan, wherein: the air intake treatment system is connected to the bottom air inlet of the fluidized bed; one end of the exhaust duct is connected to the air outlet at the top of the bag filter dust removal and vibration cleaning system, and the other end is connected to the exhaust fan; the exhaust fan is used to generate negative pressure suction, and its exhaust volume is adjusted according to the characteristics of the material in the fluidized bed and the fluidization requirements.

3. The bag filter dust collection and vibration cleaning device suitable for fluidized bed dryers according to claim 1, characterized in that: The top cylinder of the fluidized bed includes a lower cylinder, an upper cylinder, and a sealing gasket located at the connection between the two; the annular top plate of the bag frame is fixedly connected to the upper cylinder and the lower cylinder by flange bolts, and the lower surface of the annular top plate is tightly fitted with the sealing gasket to form a sealing structure.

4. The bag filter dust collection and vibration cleaning device suitable for fluidized bed dryers according to claim 1, characterized in that: The inner and outer cages of the bag frame are both composed of multiple support rods extending axially and arranged circumferentially, and multiple annular support rings distributed circumferentially, forming a cage-like support structure. The spacing between the support rods and the annular support rings is set according to the material and material characteristics of the bag.

5. The bag filter dust collector vibration cleaning device suitable for fluidized bed dryers according to claim 1, characterized in that: A sealing ring and a clamp are provided between the top of the inner bag and the inner cage, and between the top of the outer bag and the outer cage. The clamp is used to fasten the bag to the bag frame, and the sealing ring is used to ensure that airflow does not leak from the connection between the bag and the bag frame.

6. The bag filter dust collection and vibration cleaning device suitable for fluidized bed dryers according to claim 1, characterized in that: Both the inner and outer filter bags are made of filter media that are resistant to high temperatures, wear, and have good air permeability. The fiber diameter is 10-20 micrometers, the porosity is 70%-85%, the filtration accuracy is 1-10 micrometers, and the surface is treated with antistatic and anti-adhesion. The material is selected from polyester, polypropylene, polyamide, glass fiber, or polytetrafluoroethylene according to the characteristics of the material being treated.

7. A bag filter dust collector vibration cleaning device suitable for fluidized bed dryers according to claim 1, characterized in that: The number of vibration devices is 4-12, and they are evenly distributed along the circumference of the bag frame.

8. A bag filter dust collector vibration cleaning device suitable for a fluidized bed dryer according to claim 7, characterized in that: The exciter is selected from at least one of inertial exciter, electric exciter and electromagnetic exciter.

9. A bag filter dust collector vibration cleaning device suitable for a fluidized bed dryer according to claim 1, characterized in that: The vibrating plate is set on the inner and outer sides of the exciter via a connecting plate, and its plate surface has a perforated plate structure. The size and distribution of its pores are optimized according to the airflow velocity and dust particle size.

10. A bag filter dust collector vibration cleaning device suitable for a fluidized bed dryer according to claim 1, characterized in that: The flexible belt is made of rubber or engineering plastic with good elasticity and fatigue resistance. Its elastic parameters have been optimized. Its thickness is 3-8mm and its width is 30-50mm. The two ends of the flexible belt are fixedly connected to the vibrator and the insertion rod, respectively.

11. A bag filter dust collector vibration cleaning device suitable for fluidized bed dryers according to claim 1, characterized in that: The bag filter dust collector vibration cleaning system is also equipped with a differential pressure detection device and a control system. The differential pressure detection device monitors the pressure difference between the front and back sides of the filter bag in real time and transmits the data to the control system. The control system controls the start and stop of the vibrator and the vibration parameters according to the preset differential pressure threshold. When the detected differential pressure exceeds the upper limit threshold, the vibration cleaning is started. When the differential pressure drops to the lower limit threshold, the vibration is stopped.

12. A dust removal method for a bag filter vibrating cleaning device suitable for a fluidized bed dryer, as described in any one of claims 1 to 11, characterized in that, Includes the following steps: SS1. Start the fluidized bed to make the solid particles or powdered materials agitate and boil into a fluidized state, while the airflow carries the dust into the bag filter dust removal system. SS2. Obtain the airflow pressure difference data before and after the filter bag, and determine whether the filter bag has reached the state that requires cleaning based on the preset pressure difference threshold. If the pressure difference exceeds the set threshold, the cleaning operation is initiated. If the cleaning condition is not met, the airflow pressure difference is monitored. SS3. When the air pressure difference between the front and rear of the filter bag reaches the set dust removal threshold, a start command is sent to the excitation device. The exciter starts sequentially or simultaneously in a preset order and adjusts the excitation force and excitation frequency parameters of the exciter according to the size of the air pressure difference between the front and rear of the filter bag. The vibrating plate is driven to vibrate and impact the inner and outer filter bags, so that the dust attached to the surface of the filter bag is removed. SS4. Monitor the airflow pressure difference before and after the filter bag in real time. If the pressure difference is detected to return to the set normal operating range, issue a control command to stop the excitation device and terminate the current dust removal operation. If the pressure difference is not restored, continue to perform excitation dust removal until the set conditions are met. SS5. If the pressure difference across the filter bag does not return to the normal range within the set maximum cleaning time, adjust the vibration frequency and amplitude of the excitation device and perform the cleaning cycle again until the airflow of the filter bag returns to normal. SS6. After the dust removal is completed, reset the excitation device to standby mode and continue to monitor the airflow pressure difference before and after the filter bag. When the pressure difference exceeds the threshold again, repeat the dust removal process to ensure that the filter bag maintains a low resistance, high air permeability and effective dust removal working state for a long time.

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