Fluidized bed type high-purity strontium-barium material size grading device

Abstract

The invention discloses a fluidized bed type high-purity strontium-barium material size grading device which comprises a feeding system, a grading main machine, a pneumatic system, a collecting system and a control system. The grading main machine comprises a turbine grading cavity, a fluidized bed cavity and a primary air pressure stabilizing cavity which are sequentially connected from top to bottom; a modularized dynamic airflow distribution plate assembly is mounted at the junction of the fluidized bed cavity and the primary air pressure stabilizing cavity; the distribution plate assembly comprises a main plate and a plurality of independently detachable airflow generating units mounted on the main plate in an array form; each airflow generating unit comprises a unit shell, two blocking plate mechanisms and an impeller mechanism, wherein the unit shell sequentially comprises an air hole layer, a pressure stabilizing layer and an air inlet layer from top to bottom, the two blocking plate mechanisms are installed on the air inlet layer in a sliding mode, and the impeller mechanism is rotatably installed in the unit shell.

Description

Technical Field

[0001] This invention relates to the field of precision processing technology for powder materials, specifically a fluidized bed-based particle size classification device for high-purity strontium barium materials. Background Technology

[0002] High-purity strontium barium materials (such as strontium carbonate and barium nitrate) are key basic materials for high-end industries such as electronic ceramics and optical glass, and their particle size distribution directly affects the performance of downstream products. Fluidized bed air classifiers are currently the mainstream equipment for dry precision classification of micron-sized powders. However, existing technologies have the following significant drawbacks when practically processing high-purity, easily agglomerated strontium barium materials:

[0003] 1. Passive distribution plate function and poor de-agglomeration ability: Traditional fluidized beds use perforated plates or hood-type distribution plates, whose function is limited to providing a uniform and stable upward airflow. For fine strontium barium powder, which is extremely prone to soft agglomeration due to van der Waals forces, this passive airflow cannot actively apply shear force to break up the agglomerates. Undissolved clumps entering the classification zone will be misjudged as coarse particles, resulting in the loss of qualified fine powder ("coarse run-in"), or the agglomerates will break up and contaminate the coarse powder product ("fine powder trapped"), severely restricting the classification accuracy and efficiency.

[0004] 2. Maintenance is extremely difficult and costly: Traditional distribution plates and drive mechanisms are mostly integrated welded or fixed structures. Once a local vent is blocked or a drive component is damaged, the entire machine must be shut down and the entire distribution plate must be disassembled for repair or replacement. The process is time-consuming and labor-intensive, resulting in significant production interruptions and losses.

[0005] Therefore, it is necessary to provide a fluidized bed-based high-purity strontium barium material particle size classification device to solve the problems mentioned in the background art. Summary of the Invention

[0006] To achieve the above objectives, the present invention provides the following technical solution: a particle size classification device for high-purity strontium barium material based on a fluidized bed, comprising a feeding system, a classifying host, a pneumatic system, a collection system, and a control system. The classifying host includes a turbine classifying chamber, a fluidized bed chamber, and a primary air pressure stabilizing chamber connected sequentially from top to bottom. A modular dynamic airflow distribution plate assembly is installed at the junction of the fluidized bed chamber and the primary air pressure stabilizing chamber.

[0007] The distribution board assembly includes a main board and multiple independently detachable airflow generating units mounted on the main board in an array;

[0008] Each of the airflow generating units includes:

[0009] A unit housing, from top to bottom, includes a pore layer, a pressure stabilizing layer and an air intake layer. The pore layer has two main air holes and a flow stabilizing hole located between the two main air holes. The pressure stabilizing layer has a flow exchange cavity communicating with the two main air holes and the flow stabilizing hole. The air intake layer has an air intake channel communicating with the primary air pressure stabilizing cavity and the flow exchange cavity.

[0010] Two blocking mechanisms are provided, each of which is configured to correspond to one of the main air holes and can slide along the axis of the main air hole to open or close the main air hole.

[0011] An impeller mechanism is rotatably mounted in the air intake channel, and the impeller mechanism is linked with the two blockage plate mechanisms.

[0012] Furthermore, as a preferred embodiment, the main vent is a three-section composite structure, which includes a guide straight hole section, a sealing conical hole section, and a buffer expansion hole section arranged from top to bottom.

[0013] Furthermore, as a preferred embodiment, the blocking mechanism includes a slide rod and a blocking plate, wherein the slide rod is slidably disposed in the air intake layer, and the blocking plate is fixedly disposed at the top end of the slide rod.

[0014] Furthermore, as a preferred embodiment, the plug is a conical plunger that mates with the sealing conical bore section, and its sliding stroke is configured such that when the plug moves to the open position, its sealing conical surface can completely disengage from the sealing conical bore section.

[0015] Furthermore, as a preferred embodiment, the sealing cone surface of the plug plate is provided with an elastic sealing element, and the maximum outer diameter of the conical plunger is smaller than the maximum outer diameter of the sealing cone hole section.

[0016] Furthermore, as a preferred embodiment, the impeller mechanism includes a ring plate and blades, the ring plate is rotatably mounted in the air intake channel, and an annular groove for accommodating the ring plate is provided on the inner side of the air intake channel, and multiple blades are fixedly arranged circumferentially on the inner side of the ring plate.

[0017] Furthermore, preferably, a guide rod is fixedly provided on the slide rod;

[0018] The ring plate has two concentric arc-shaped grooves offset along its height direction, and a spiral groove connecting the two arc-shaped grooves. The two arc-shaped grooves and the two spiral grooves together form a guide groove that is connected end to end. The guide rod is slidably disposed along the guide groove.

[0019] Furthermore, as a preferred embodiment, the primary air pressure stabilizing chamber is a straight cylindrical flat structure with at least one air inlet provided along the tangent on its side.

[0020] Furthermore, as a preferred embodiment, the pneumatic system includes a gas circulation pipeline for partially circulating and returning the exhaust gas discharged from the collection system to the inlet of the primary air pressure stabilizing chamber after filtration and drying.

[0021] Compared with the prior art, the present invention provides a particle size classification device based on fluidized bed high-purity strontium barium material, which has the following beneficial effects:

[0022] 1. By integrating thousands of self-driven "airflow generation units" on the distribution plate, each unit can independently generate high-frequency alternating jet airflow. This dynamic shear flow field with staggered phases generated throughout the bottom of the fluidized bed can exert strong active shearing and impact on powder agglomerates, thereby achieving near-complete deagglomeration before the material enters the classification zone. This ensures that the material entering the turbine classification zone is a fully dispersed single particle, fundamentally solving the problems of "coarse particles running away" and "fine particles being trapped" caused by agglomeration. This results in a steeper classification and cutting curve, a narrower product particle size distribution, and greatly improves classification efficiency and accuracy.

[0023] 2. This invention eliminates any external power source and innovatively utilizes airflow to drive the impeller mechanism. The rotation of the impeller is then directly converted into the reciprocating motion of the blocking plate through a precise slotted cam linkage mechanism (the arc-shaped slot and spiral slot on the ring plate). This design constitutes a fully embedded, physical "airflow input-mechanical action" positive feedback closed loop. That is, as long as the system supplies air, it can provide power. In principle, it completely eliminates the risk of operation interruption caused by loss of external signals, power failure, or "dead points" of the mechanism, ensuring that the device can operate continuously and stably.

[0024] 3. The "airflow generation unit" is designed as a standardized, independently detachable module. When a single unit is damaged, the operator can quickly replace it directly from below the main board of the distribution board after shutdown, without having to disassemble the entire bulky distribution board or shut down for several days. This greatly reduces maintenance time, improves equipment availability, and lowers the total life cycle maintenance cost. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the hierarchical host in this invention;

[0026] Figure 2 This is a schematic diagram of the primary air pressure stabilizing chamber and the main board in this invention;

[0027] Figure 3 This is a schematic diagram of the airflow generating unit in this invention;

[0028] Figure 4 This is a schematic cross-sectional view of the unit housing in this invention;

[0029] Figure 5This is a schematic diagram of the blocking plate mechanism in this invention;

[0030] Figure 6 This is a schematic diagram of the impeller mechanism in this invention;

[0031] In the diagram: 1. Turbine stage chamber; 2. Fluidized bed chamber; 21. Feed inlet; 22. Observation window; 3. Primary air pressure stabilizing chamber; 31. Air inlet; 4. Main board; 5. Airflow generating unit; 51. Unit shell; 511. Porous layer; 512. Pressure stabilizing layer; 513. Air intake layer; 514. Main air hole; 514a. Guide straight hole section; 514b. Sealing cone hole section; 514c. Buffer expansion hole section; 515. Flow stabilizing hole; 516. Flow exchange hole; 517. Air intake channel; 52. Blocking plate mechanism; 521. Slide rod; 522. Blocking plate; 523. Elastic sealing element; 524. Guide rod; 53. Impeller mechanism; 531. Ring plate; 532. Blade; 533. Arc groove; 534. Spiral groove. Detailed Implementation

[0032] Please see Figures 1-6 In this embodiment of the invention, a particle size classification device for high-purity strontium barium material based on a fluidized bed includes a feeding system, a classification host, a pneumatic system, a collection system, and a control system (not shown in the figure). The classification host constitutes the core of the device and includes a turbine classification chamber 1, a fluidized bed chamber 2, and a primary air pressure stabilizing chamber 3, which are sequentially sealed and connected from top to bottom. The turbine classification chamber 1 is equipped with a turbine classification rotor (not shown in the figure) driven by a high-speed motor, which is used to perform final centrifugal precision classification of the rising powder. The fluidized bed chamber 2 is a straight cylindrical structure with a feed inlet 21 and an observation window 22 on its side wall. The primary air pressure stabilizing chamber 3 is also a straight cylindrical flat-bottom structure with at least one air inlet 31 on its side along the tangential direction, which is used to receive dry and clean compressed air from the main fan (belonging to the pneumatic system). Tangential air intake is beneficial to forming a rotating flow field in the pressure stabilizing chamber 3, further promoting pressure equalization.

[0033] The core structure of the modular dynamic airflow distribution plate assembly:

[0034] At the junction of the fluidized bed chamber 2 and the primary air pressure stabilizing chamber 3, a modular dynamic airflow distribution plate assembly is installed. The distribution plate assembly consists of a main board 4 and more than 2,000 independently detachable airflow generating units 5 mounted on it in an array. The main board 4 is a 316L stainless steel plate with a thickness of 35mm and precision mounting holes corresponding to the unit array are machined on it. The airflow generating units 5 are pushed in from the bottom of the mounting holes and snapped into the mounting holes.

[0035] Detailed internal structure and working mechanism of airflow generating unit 5:

[0036] The core of each airflow generating unit 5 is a one-piece machined unit shell 51. For clear functional division, the shell 51 can be conceptually divided into three layers from top to bottom: air pore layer 511, pressure stabilizing layer 512 and air intake layer 513.

[0037] Porous layer 511: Located at the top, its top surface is in direct contact with the material in the fluidized bed chamber 2. This layer is processed with two main air holes 514 and a flow stabilizing hole 515 located between them. The main air holes 514 are a key three-section composite structure, including from top to bottom:

[0038] Guide straight hole section 514a: provides precise guidance.

[0039] Sealing cone section 514b: achieves a sealing fit.

[0040] Buffer expansion orifice section 514c: Reduces inlet airflow resistance.

[0041] The flow stabilizing orifice 515 is a simple straight orifice with a diameter significantly smaller than that of the main air orifice 514, to ensure that a portion of the airflow flows through it constantly.

[0042] Pressure stabilizing layer 512: Located in the middle layer, it has a relatively spacious exchange cavity 516. The exchange cavity 516 is connected to the buffer expansion section of the two main air holes 514 above and the lower end of the flow stabilizing hole 515, which plays the role of temporarily storing and distributing airflow.

[0043] Air intake layer 513: Located at the bottom layer, it has an air intake channel 517. The upper end of the air intake channel 517 is connected to the converter cavity 516, and the lower end opening serves as the air intake interface of unit 5, which is connected to the mounting hole of the main board 4, thereby communicating with the primary air pressure stabilizing cavity 3.

[0044] Blocking mechanism 52: Each main air hole 514 is equipped with a blocking mechanism 52, which includes a vertically arranged slide rod 521 and a blocking plate 522 fixed at its top. The slide rod 521 is slidably arranged in the guide hole of the air intake layer 513 through a linear bearing (not shown in the figure). The blocking plate 522 is a conical plunger that cooperates with the sealing conical section of the main air hole 514, and an elastic sealing element 523 (such as an O-ring) is embedded on its conical surface.

[0045] Specifically, the maximum outer diameter of the conical plunger is slightly smaller than the maximum inner diameter of the sealing conical bore section, ensuring that there is a micron-level annular gap between the two. The sliding stroke of the plug plate 522 is precisely designed so that when it moves to the lowest open position, its entire sealing conical surface can completely disengage from the sealing conical bore section of the main air hole 514, allowing airflow to pass through without obstruction.

[0046] Impeller mechanism 53 and linkage settings: Impeller mechanism 53 is the self-driving core of the unit, and its rotation is installed in the air intake channel 517.

[0047] Specifically, the impeller mechanism 53 includes an annular plate 531 and multiple blades 532 fixed inside the annular plate 531. The inner wall of the air intake channel 517 is provided with an annular groove. The annular plate 531 is supported in this annular groove by a miniature ceramic ball bearing (not shown in the figure) and can rotate freely. When the airflow flows upward through the air intake channel 517 to the converter chamber 516, the airflow will drive the blades 532 to rotate, so that the entire impeller mechanism 53 will continue to rotate.

[0048] To convert the rotational motion of the impeller mechanism 53 into the alternating linear motion of the two blocking plates 522, this invention employs a unique slotted cam linkage mechanism. A guide rod 524 is fixedly installed at the lower part of the slide rod 521. On the ring plate 531, two arc-shaped grooves 533 concentric with the ring plate 531 are machined along its height direction, and two spiral grooves 534 connect the ends of the upper and lower arc-shaped grooves 533. These two arc-shaped grooves 533 and two spiral grooves 534 together form a closed "guide groove" on the end face of the ring plate 531. The end of the guide rod 524 is embedded in this guide groove and can slide along this guide groove.

[0049] Work process:

[0050] After the device is started, the main fan sends the dry gas into the primary air pressure stabilizing chamber 3. The gas then enters the air intake channel 517 of each airflow generating unit 5 and enters the exchange chamber 516. The airflow flowing through the air intake channel 517 can drive the blades 532 of the impeller mechanism 53, causing the ring plate 531 to start rotating at a constant speed. Subsequently, the airflow entering the exchange chamber 516 will be split into two main air holes 514 and one flow stabilizing hole 515.

[0051] The rotation of the ring plate 531 drives the closed guide groove on its end face to move. Since the guide rod 524 is restricted to the straight track of the slide rod 521, the specific shape of the guide groove (including the horizontal arc section and the inclined spiral section) forces the guide rod 524 to slide along the guide groove, thereby driving the slide rod 521 and the blocking plate 522 to reciprocate linear motion according to the preset law. By precisely designing the phase difference of the two spiral grooves 534, the motion states of the two slide rods 521 and the blocking plate 522 are always opposite: when one blocking plate 522 is raised to the highest point (closing the main air hole 514), the other blocking plate 522 just falls to the lowest point (opening the main air hole 514). As the impeller continues to rotate, the two main air holes 514 open and close alternately at a fixed frequency determined by the impeller speed.

[0052] This alternating jetting airflow generates strong local shear and disturbance at the bottom of the fluidized bed, which can efficiently disperse soft agglomerates in high-purity strontium barium micro powder. The fully dispersed single particles rise under the carrying force of the fluidized airflow and enter the turbine classification chamber 1 for precise classification. Fine particles are collected as products by the collection system (such as cyclone separators and bag filters), while coarse particles are discharged from the side wall of the fluidized bed or the bottom of the classifier, thereby effectively improving the classification accuracy and rate.

[0053] In particular, all core moving parts of the airflow generating unit (such as the blocking plate 522, impeller mechanism 53, and ring plate 531) can be made of zirconia ceramic or inert, wear-resistant engineering materials. The internal flow channels and moving mechanisms of the entire unit are completely enclosed, and only the fixed surface of the air outlet is in contact with the material, thereby fundamentally eliminating product contamination caused by metal wear.

[0054] As another embodiment of the present invention, the pneumatic system may further include a gas circulation pipeline (not shown in the figure), which collects the exhaust gas discharged from the system, performs high-efficiency filtration and deep drying, and then recycles a portion of it back to the inlet of the main blower or directly back to the air inlet 31 of the primary air pressure stabilizing chamber 3. This design can significantly reduce the consumption of fresh gas, especially when using inert gas as process gas, resulting in significant economic benefits.

[0055] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A particle size classification device for high-purity strontium barium material based on a fluidized bed, comprising a feeding system, a classifying main unit, a pneumatic system, a collection system, and a control system, characterized in that, The staged host includes a turbine staged chamber (1), a fluidized bed chamber (2) and a primary air pressure stabilizing chamber (3) connected from top to bottom. A modular dynamic airflow distribution plate assembly is installed at the junction of the fluidized bed chamber (2) and the primary air pressure stabilizing chamber (3). The distribution board assembly includes a main board (4) and multiple independently detachable airflow generating units (5) mounted in an array on the main board (4); Each of the airflow generating units (5) includes: A unit housing (51) includes, from top to bottom, a pore layer (511), a pressure stabilizing layer (512), and an air intake layer (513). The pore layer (511) has two main air holes (514) and a flow stabilizing hole (515) located between the two main air holes (514). The pressure stabilizing layer (512) has a converter cavity (516) communicating with the two main air holes (514) and the flow stabilizing hole (515). The air intake layer (513) has an air intake channel (517) communicating with the primary air pressure stabilizing cavity (3) and the converter cavity (516). Two blocking mechanisms (52) are provided, each of which is configured corresponding to one of the main air holes (514) and can slide along the axis of the main air hole (514) to open and close the main air hole (514); An impeller mechanism (53) is rotatably mounted in the air intake channel (517), and the impeller mechanism (53) is linked with the two block plate mechanisms (52).

2. The particle size classification device based on fluidized bed high-purity strontium barium material according to claim 1, characterized in that, The main vent (514) is a three-section composite structure, which includes a guide straight hole section, a sealing conical hole section and a buffer expansion hole section arranged from top to bottom.

3. The particle size classification device based on fluidized bed high-purity strontium barium material according to claim 2, characterized in that, The blocking mechanism (52) includes a slide rod (521) and a blocking plate (522). The slide rod (521) is slidably disposed in the air intake layer (513), and the blocking plate (522) is fixedly disposed at the top end of the slide rod (521).

4. The particle size classification device based on fluidized bed high-purity strontium barium material according to claim 3, characterized in that, The plug (522) is a conical plunger that mates with the sealing conical hole section. Its sliding stroke is configured such that when the plug (522) moves to the open position, its sealing conical surface can completely disengage from the sealing conical hole section.

5. The particle size classification device based on fluidized bed high-purity strontium barium material according to claim 4, characterized in that, The sealing cone surface of the plug (522) is provided with an elastic sealing element (523), and the maximum outer diameter of the conical plunger is smaller than the maximum outer diameter of the sealing cone hole section.

6. The particle size classification device based on fluidized bed high-purity strontium barium material according to claim 3, characterized in that, The impeller mechanism (53) includes a ring plate (531) and blades (532). The ring plate (531) is rotatably installed in the air intake channel (517), and an annular groove for accommodating the ring plate (531) is provided on the inner side of the air intake channel (517). Multiple blades (532) are fixedly arranged circumferentially on the inner side of the ring plate (531).

7. The particle size classification device based on fluidized bed high-purity strontium barium material according to claim 6, characterized in that, A guide rod (524) is fixedly installed on the slide rod (521); The ring plate (531) has two arc-shaped grooves (533) that are concentric with the ring plate (531) and a spiral groove (534) that connects the two arc-shaped grooves (533). The two arc-shaped grooves (533) and the two spiral grooves (534) together form a guide groove that is connected end to end. The guide rod (524) is slidably arranged along the guide groove.

8. The particle size classification device for high-purity strontium barium material based on fluidized bed as described in claim 1, characterized in that, The primary air pressure stabilizing chamber (3) is a straight cylindrical flat structure with at least one air inlet (31) arranged along the tangent on its side.

9. The particle size classification device based on fluidized bed high-purity strontium barium material according to claim 1, characterized in that, The pneumatic system includes a gas circulation pipeline, which is used to partially circulate and return the exhaust gas discharged from the collection system to the inlet of the primary air pressure stabilizing chamber (3) after filtration and drying.

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