A dehumidification device for hexagonal boron nitride

Abstract

The utility model discloses a kind of dehumidification devices for hexagonal boron nitride, solve the problem of poor drying uniformity, low dehumidification efficiency in prior art.The utility model includes drying cabinet, and heating mechanism, dehumidification feed mechanism and wet extraction mechanism are equipped on drying cabinet;Drying tray and the first rotating shaft of hollow setting are equipped in drying cabinet, rake claw subassembly is equipped on the first rotating shaft, and rake claw subassembly corresponds with drying tray;Dehumidification feed mechanism includes material box, and stirrer is equipped in material box;The heat outlet of heating mechanism is connected with material box and the first rotating shaft respectively and communicates;The first rotating shaft is equipped with a plurality of air outlet holes.The utility model drying cabinet, heating mechanism, dehumidification feed mechanism and wet extraction mechanism work cooperatively, form closed loop dehumidification system;Heating mechanism directly heats material box and the first rotating shaft, and heat is evenly diffused to drying tray through the air outlet hole on rotating shaft, realize the stereoscopic heating of hexagonal boron nitride powder, avoid the local overheating or uneven drying caused by traditional single heat source.

Description

Technical Field

[0001] This utility model relates to the field of chemical equipment technology, and in particular to a dehumidification device. Background Technology

[0002] Hexagonal boron nitride (h-BN), commonly known as "white graphite," has a layered crystal structure with a theoretical density of 2.27 g / cm³ and a Mohs hardness of 1–2. It is highly susceptible to "water-induced agglomeration" in humid environments due to the adsorption of water molecules between its layers. Field tests in production show that when the relative humidity is >60%, h-BN powder with an average particle size of 5 μm can form pseudo-agglomerates >2 mm in size within 24 hours, with a moisture content of 3%–7% (mass fraction). If these agglomerates are directly introduced into high-temperature sintering or hot-pressing processes, they will cause "water explosion" defects due to instantaneous vaporization, leading to cracking of ceramic parts, interruption of heat conduction channels, and a 15%–30% decrease in yield.

[0003] Currently, the commonly used drying methods in the industry mainly include: 1. Static tray drying ovens, where the damp h-BN is spread flat on a stainless steel tray and statically dried at 80-120℃; however, its heat conduction path is long, the temperature difference between the center and the surface is >15℃, and the drying uniformity is poor. 2. Rotary vacuum dryers, which utilize rotating drums and vacuum drying; such as the hexagonal boron nitride recovery drying device with authorization announcement number CN117091367B; its structure is complex, the overall weight is large, and the cost is high. Therefore, for industrial production, it is necessary to design a dehumidification equipment that provides uniform drying, high drying efficiency, and low cost. Utility Model Content

[0004] To address the shortcomings in the aforementioned background technology, this utility model proposes a dehumidification device for hexagonal boron nitride, which solves the problems of poor drying uniformity and low dehumidification efficiency in the prior art.

[0005] The technical solution of this utility model is implemented as follows: A dehumidification device for hexagonal boron nitride includes a drying chamber, which is equipped with a heating mechanism, a dehumidification feeding mechanism, and a dehumidification mechanism. The drying chamber contains a drying tray and a hollow first rotating shaft, which is connected to a drive motor located at the bottom of the drying chamber. A rake assembly is mounted on the first rotating shaft, corresponding to the drying tray. The dehumidification feeding mechanism includes a material box containing a stirrer. The heat outlet of the heating mechanism is connected to both the material box and the first rotating shaft. The first rotating shaft has several air outlets. The dehumidification feeding mechanism performs stirring and hot air drying during the feeding process, performing a first dehumidification of the hexagonal boron nitride material, which then undergoes a second dehumidification in the drying chamber, improving dehumidification efficiency. The heating mechanism works in conjunction with the drying tray to improve drying uniformity. The rake assembly dynamically turns the material between the material and the drying tray, further improving drying efficiency. This utility model adopts an integrated design, occupies little space, and has high drying efficiency, further improving dehumidification efficiency.

[0006] Further optimized, the drying chamber is detachably equipped with a support frame, on which the heating mechanism, dehumidifying feeding mechanism, and dehumidification mechanism are all mounted. The heating mechanism includes a hot air blower, with its hot air outlet connected to a first pipe and a second pipe. The first pipe is connected to a first rotating shaft via a rotary joint, and the second pipe is connected to an air inlet pipe located on the material box. The heat from the hot air blower enters the material box and the drying chamber through two separate paths, with independent proportional adjustment of the two hot air paths, reducing energy consumption while ensuring drying efficiency.

[0007] In a further preferred embodiment, the dehumidification mechanism includes a dehumidifying fan, the exhaust port of which is connected to an exhaust vent installed on the drying chamber. The dehumidifying fan is used to promptly collect moisture from inside the chamber, preventing "dampness from returning."

[0008] Further preferably, the agitator includes a vertically arranged agitator shaft inside the material box, with several downwardly inclined agitator bars on the shaft, and the top of the agitator shaft connected to a first motor mounted on the material box. Preferably, the upper part of the material box is equipped with a circulating fan and a feed hopper; the circulating fan allows hot air to circulate within the material box, improving the efficiency of the first drying step.

[0009] In a further preferred embodiment, the drying tray is fixed inside the drying chamber by a support frame. The drying tray includes a large tray and a small tray, which are alternately arranged and spaced apart along the first rotating shaft. A flow channel is provided at the center of the large tray, and a baffle ring is provided at the outer edge of the large tray. The large and small trays, together with the rotating rake claw assembly, can achieve self-unloading while increasing the drying area and improving drying efficiency.

[0010] Further optimization involves hollow cavities inside both the large and small discs, with inlet and outlet heat pipes installed within the drying chamber; both inlet and outlet heat pipes are connected to the hollow cavities. A heat source (usually steam or hot oil) enters the large and small discs through the inlet riser, ensuring uniform heating of the discs and guaranteeing even heating of the sludge.

[0011] Further preferably, the rake claw assembly includes rake arms arranged at equal angles along the circumference of the first rotating axis, a plurality of rake frames arranged along its axial direction on the rake arms, and rake claws at the lower part of the rake frames; ensuring that the material on the drying tray can be pushed downwards while being turned over and stirred.

[0012] Further optimized, the rake frame is a Y-shaped frame, with the vertical rod being a threaded rod that engages with positioning holes on the rake arm and is secured by nuts. The rake claws corresponding to the large disc are inclined inwards, while the rake claws corresponding to the small disc are inclined outwards. During rotation, the rake claws corresponding to the large disc can push the material inwards to the central flow channel, while the rake claws corresponding to the small disc can push the material outwards to the outer edge and scatter it below.

[0013] Further optimization involves a receiving tray at the bottom of the drying chamber, with a discharge hopper on the tray; a scraper corresponding to the receiving tray is mounted on the first rotating shaft. Under the action of the first rotating shaft, the scraper scrapes the material on the receiving tray to the discharge hopper, facilitating smooth discharge.

[0014] The beneficial effects of this utility model are as follows: In this utility model, the drying box, heating mechanism, dehumidifying feeding mechanism, and dehumidifying mechanism work together to form a closed-loop dehumidification system; the heating mechanism directly heats the material box and the first rotating shaft, and the heat is evenly diffused to the drying tray through the air outlet on the rotating shaft, realizing three-dimensional heating of hexagonal boron nitride powder, avoiding local overheating or uneven drying caused by traditional single heat sources; this device solves the traditional problems of h-BN being prone to agglomeration and uneven drying by means of directional heat transfer, dynamic turning, and immediate moisture discharge, and has the advantages of high efficiency, energy saving, and continuous production. At the same time, its modular design provides a flexible expansion path for large-scale application.

[0015] This invention employs a dehumidifying feeding mechanism for pretreatment: a built-in agitator in the feed hopper pre-stirs the h-BN powder before feeding, breaking up powder agglomerations caused by moisture, ensuring uniform feeding, and preventing the drying tray from reducing efficiency due to the accumulation of large particle agglomerates. Furthermore, gentle drying avoids structural damage: h-BN has a layered structure, and traditional high-temperature drying easily damages its crystal integrity; this device achieves gentle dehydration by combining uniform low-temperature hot air (the temperature can be precisely controlled by the heating mechanism) with dynamic tumbling, preserving the layered structure and properties of h-BN. The hollow design of the first rotating shaft serves as a heat transfer channel, directly introducing the heat energy from the heating mechanism into the drying chamber, reducing heat loss during the transfer process; the layout of the air vents allows hot air to penetrate the material layer from bottom to top, forming convection and reducing energy consumption. The rake claw assembly rotates with the first rotating shaft, continuously tumbling the h-BN powder on the drying tray, increasing the contact area between the material and hot air, accelerating moisture evaporation, and preventing powder agglomeration or adhesion to the bottom of the tray, significantly improving drying efficiency. Attached Figure Description

[0016] To more clearly illustrate the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the internal structure of the drying oven of this utility model; Figure 3 This is a schematic diagram of the dehumidification feeding mechanism; Figure 4 This is a schematic diagram of the rake claw assembly. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Example 1, such as Figure 1 As shown, a dehumidification device for hexagonal boron nitride includes a drying chamber 1, which is equipped with a heating mechanism 2, a dehumidification feeding mechanism 3, and a dehumidification mechanism 4. This dehumidification device integrates feeding dehumidification, main drying, heating, and dehumidification into one unit, occupying a small area and having a compact structure. The drying chamber 1 contains a drying tray 5 and a hollow first rotating shaft 6. The first rotating shaft 6 is connected to a drive motor 8 located at the bottom of the drying chamber 1, providing power for the rotation of the first rotating shaft. A rake assembly 7 is mounted on the first rotating shaft 6, corresponding to the drying tray 5. Specifically, a heat source is provided inside the drying tray. While the hexagonal boron nitride material falls onto the drying tray through the dehumidification feeding mechanism for drying, the drive motor drives the first rotating shaft and the rake assembly to rotate. The rake assembly tumbles and pushes the material on the drying tray, improving drying efficiency and uniformity.

[0020] like Figure 3 As shown in the preferred embodiment, the dehumidification feeding mechanism 3 includes a material box 31, inside which a stirrer 32 is installed. The stirrer agitates the internal materials to prevent clumping. The heat outlet of the heating mechanism 2 is connected to the material box 31 and the first rotating shaft 6. The first rotating shaft 6 is provided with several air outlets 61. The hollow design of the first rotating shaft serves as a heat transfer channel, directly introducing the heat energy of the heating mechanism into the drying chamber, reducing heat loss during the transfer process. The layout of the air outlets allows hot air to penetrate the material layer from bottom to top, forming convection and reducing energy consumption. The heating mechanism is connected to the material box for the first drying and dehumidification; the heating mechanism and the first rotating shaft are used for "pulse-type" air blowing drying of the materials in the drying chamber, improving the drying efficiency in the drying chamber. In this utility model, the drying chamber, heating mechanism, dehumidification feeding mechanism, and dehumidification mechanism work together to form a closed-loop dehumidification system. The heating mechanism directly heats the material bin and the first rotating shaft. The heat is evenly diffused to the drying tray through the air vents on the shaft, achieving three-dimensional heating of the hexagonal boron nitride (h-BN) powder and avoiding localized overheating or uneven drying caused by traditional single heat sources. This device, through a synergistic mechanism of directional heat transfer, dynamic turning, and immediate moisture removal, specifically addresses the traditional problems of h-BN's tendency to agglomerate due to moisture and uneven drying, while also offering advantages such as high efficiency, energy saving, and continuous production.

[0021] Example 2, a dehumidification device for hexagonal boron nitride, is further optimized based on Example 1. In this example, a detachable support 10 is provided on the drying chamber 1, and the heating mechanism 2, dehumidification feeding mechanism 3, and dehumidification mechanism 4 are all mounted on the support 10. The heating mechanism 2, dehumidification feeding mechanism 3, and dehumidification mechanism 4 form a modular design with the drying chamber through the detachable support, providing a flexible expansion path for large-scale applications. As a preferred embodiment, the heating mechanism 2 includes a hot air blower 21. The hot air outlet of the hot air blower 21 is connected to a first pipe 22 and a second pipe 23, respectively. The first pipe 22 is connected to a first rotating shaft 6 through a rotary joint. The hot air from the hot air blower 21 is directly introduced into the hollow first rotating shaft 6 through the rotary joint, forming a "axial heating" mode. The hot air is radially sprayed from the air outlet on the rotating shaft, forming a uniform hot air "umbrella" at the drying tray 5, which can perform penetrating drying. The hot air penetrates the h-BN powder layer from bottom to top, carrying away moisture and avoiding the problem of excessive dryness on the surface and dampness at the bottom caused by traditional top air supply. The second pipe 23 is connected to the air inlet pipe 33 installed on the material box 31; the air enters the material box 31 through the air inlet pipe 33 to pre-dry the moist h-BN powder: preheating and viscosity reduction: hot air evaporates the free water on the powder surface in advance, reducing the tendency to agglomerate, so that the material entering the drying tray later is in a loose state. The first pipe 22 and the second pipe 23 can be equipped with electric regulating valves for independent control; the dehumidification mechanism 4 includes a dehumidification fan 41, and the air intake of the dehumidification fan 41 is connected to the air intake 11 installed on the drying box 1. The dehumidification fan 41 forms a continuous negative pressure in the drying box 1 through the air intake 11, so that the water vapor partial pressure on the surface of the h-BN powder is always lower than the equilibrium vapor pressure, thereby increasing the evaporation driving force and improving the drying rate. The air intake 11 has a built-in sintered metal filter screen to intercept h-BN dust, which not only prevents wear on the blades of the dehumidification fan 41, but also avoids product loss.

[0022] In this embodiment, preferably, the stirrer 32 includes a stirring shaft 3201 vertically arranged in the material box 31, and a plurality of downwardly inclined stirring rods 3202 are provided on the stirring shaft 3201. The top end of the stirring shaft 3201 is connected to a first motor 3203 arranged on the material box 31. The first motor provides the power for the rotation of the stirring shaft. The "downward inclination" design of the stirring rods 3202 is preferably such that the stirring rods 3202 are inclined downward at an angle of 15° to 30° with the horizontal plane. This generates axial thrust when rotating, actively pressing the h-BN powder towards the bottom outlet of the material box 31, thus improving the stability of the feeding. The upper part of the material bin 31 is also equipped with a circulating fan 3204 and a feeding hopper 3205; the feeding hopper is used for adding materials; the circulating fan 3204 can be started after hot air is introduced, which can make the hot air in the material bin circulate and improve the feeding and drying efficiency; at the same time, the positive pressure airflow causes the h-BN dust generated during feeding to settle downwards; combined with the downward thrust of the stirring rod, it reduces the escape of dust and achieves dust-free feeding.

[0023] Example 3, as Figure 2 As shown, a dehumidification device for hexagonal boron nitride is further optimized based on embodiment 1 or 2. In this embodiment, the drying tray 5 is fixed inside the drying chamber 1 by a support frame 13. The drying tray 5 includes a large tray 51 and a small tray 52. ​​In this embodiment, two large trays and two small trays are used as an example. The large trays 51 and small trays 52 are alternately and spaced along the first rotating shaft 6. A flow channel 53 is provided at the center of the large tray 51, and a baffle ring 54 is provided at the outer edge of the large tray 51. The flow channel is used for the downward flow of material on the large tray, and the baffle ring prevents the material from scattering from the outer circle. In this embodiment, the scheme of alternating large and small trays + central flow channel is made into an integral support frame module, which essentially solves the three things of heating, material feeding, and gas distribution at one time in the axial height, thereby improving the evaporation intensity. There are no notches on the edge of the large tray, and the rake pushes all the material towards the central hole; the small tray does the opposite, throwing the material towards the outer ring; thus, continuous and uniform material feeding is achieved. The material undergoes four drying processes from top to bottom, improving the drying efficiency.

[0024] Specifically, both the large disc 51 and the small disc 52 have hollow cavities inside, and the drying chamber 1 is equipped with a heat inlet pipe 14 and a heat outlet pipe 15; both the heat inlet pipe 14 and the heat outlet pipe 15 are connected to the hollow cavities. The heat source (usually steam or hot oil) enters the large and small discs through the heat inlet riser, so that the discs are heated evenly, ensuring that the sludge is heated evenly.

[0025] In this embodiment, the rake claw assembly 7 includes rake arms 71 arranged at equal angles along the circumference of the first rotating shaft 6, typically 2 to 4 rake arms; each rake arm 71 is provided with several rake frames 72 arranged along its axial direction, and rake claws 73 are provided at the lower part of the rake frames 72. Each rake arm 71 is fitted with 3 to 6 detachable rake frames 72; under the action of the first rotating shaft, the rake claws rotate on the drying disc, turning and pushing the material. In this embodiment, the large disc is located at the top, and the material first falls onto the large disc, then is spread and turned under the action of the rake claws, and finally pushed to the central channel, falling onto the small disc. Then the material on the small disc is also spread and turned under the action of the rake claws, and finally pushed to the outer edge and falling onto the large disc below; this process is repeated to perform multi-stage drying of the material, ensuring drying uniformity and dehumidification efficiency.

[0026] like Figure 4 As shown, in this embodiment, the rake frame 72 is a Y-shaped frame, and the vertical part of the Y-shaped frame is a threaded rod 721. The threaded rod 721 cooperates with the positioning hole provided on the rake arm 71 and is fixed by a nut 722. By rotating the threaded rod, the tilt angle of the rake claws can be changed. The screw can be locked with double nuts to ensure stability. The rake claws 73 corresponding to the large disc 51 are tilted inward to gather the material into the central flow channel for easy downward discharge. The rake claws 73 corresponding to the small disc 52 are tilted outward to push the material to the outer edge for easy downward discharge.

[0027] In this embodiment, a receiving tray 12 is provided at the bottom of the drying chamber 1, and a discharge hopper 16 is provided on the receiving tray 12; a scraper 17 corresponding to the receiving tray 12 is provided on the first rotating shaft 6. The scraper rotates under the action of the first rotating shaft, scraping the material on the receiving tray to the discharge hopper, so as to facilitate smooth discharge.

[0028] This invention employs a dehumidifying feeding mechanism for pretreatment: a built-in agitator in the feed hopper pre-stirs the h-BN powder before feeding, breaking up powder agglomerations caused by moisture, ensuring uniform feeding, and preventing the drying tray from reducing efficiency due to the accumulation of large particle agglomerates. Furthermore, gentle drying avoids structural damage: h-BN has a layered structure, and traditional high-temperature drying easily damages its crystal integrity; this device achieves gentle dehydration by combining uniform low-temperature hot air (with precise temperature control by the heating mechanism) with dynamic tumbling, preserving the layered structure and properties of h-BN. Through a synergistic mechanism of directional heat transfer, dynamic tumbling, and immediate moisture removal, this device specifically solves the traditional problems of h-BN's tendency to agglomerate due to moisture and uneven drying, offering advantages such as high efficiency, energy saving, and continuous production. Its modular design also provides a flexible expansion path for large-scale applications.

[0029] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A dehumidification device for hexagonal boron nitride, comprising a drying oven (1), characterized in that: The drying chamber (1) is equipped with a heating mechanism (2), a dehumidifying feeding mechanism (3) and a dehumidifying mechanism (4); the drying chamber (1) is equipped with a drying tray (5) and a hollow first rotating shaft (6), the first rotating shaft (6) is connected to a drive motor (8) located at the bottom of the drying chamber (1), the first rotating shaft (6) is equipped with a rake claw assembly (7), the rake claw assembly (7) is corresponding to the drying tray (5); the dehumidifying feeding mechanism (3) includes a material box (31), the material box (31) is equipped with a stirrer (32); the heat outlet of the heating mechanism (2) is connected to the material box (31) and the first rotating shaft (6) respectively; the first rotating shaft (6) is equipped with several air outlets (61).

2. The dehumidification device for hexagonal boron nitride according to claim 1, characterized in that: The drying box (1) is detachably equipped with a support (10), and the heating mechanism (2), the dehumidifying feeding mechanism (3) and the dehumidifying mechanism (4) are all installed on the support (10); the heating mechanism (2) includes a hot air blower (21), and the hot air outlet of the hot air blower (21) is connected to a first pipe (22) and a second pipe (23) respectively. The first pipe (22) is connected to the first rotating shaft (6) through a rotary joint, and the second pipe (23) is connected to the air inlet pipe (33) installed on the material box (31).

3. The dehumidification device for hexagonal boron nitride according to claim 2, characterized in that: The dehumidification mechanism (4) includes a dehumidification fan (41), and the exhaust port of the dehumidification fan (41) is connected to the exhaust port (11) provided on the drying box (1).

4. The dehumidification device for hexagonal boron nitride according to any one of claims 1 to 3, characterized in that: The agitator (32) includes a stirring shaft (3201) vertically arranged in the material box (31), and a number of downwardly inclined stirring rods (3202) are provided on the stirring shaft (3201). The top of the stirring shaft (3201) is connected to a first motor (3203) arranged on the material box (31).

5. The dehumidification device for hexagonal boron nitride according to claim 4, characterized in that: The upper part of the material box (31) is equipped with a circulating fan (3204) and a feeding hopper (3205).

6. The dehumidification device for hexagonal boron nitride according to any one of claims 1 to 3 and 5, characterized in that: The drying tray (5) is fixed inside the drying box (1) by a support frame (13). The drying tray (5) includes a large tray (51) and a small tray (52). The large tray (51) and the small tray (52) are arranged alternately and at intervals along the first rotating shaft (6). A flow channel (53) is provided at the center of the large tray (51), and a baffle ring (54) is provided on the outer edge of the large tray (51).

7. The dehumidification device for hexagonal boron nitride according to claim 6, characterized in that: Both the large plate (51) and the small plate (52) have hollow inner cavities. The drying oven (1) is equipped with a heat inlet pipe (14) and a heat outlet pipe (15); both the heat inlet pipe (14) and the heat outlet pipe (15) are connected to the hollow inner cavity.

8. The dehumidification device for hexagonal boron nitride according to claim 7, characterized in that: The rake claw assembly (7) includes a rake arm (71) arranged at equal angles along the circumference of the first rotating shaft (6), a number of rake frames (72) arranged along its axial direction on the rake arm (71), and a rake claw (73) at the lower part of the rake frame (72).

9. The dehumidification device for hexagonal boron nitride according to claim 8, characterized in that: The rake frame (72) is a Y-shaped frame. The vertical part of the Y-shaped frame is a threaded rod (721). The threaded rod (721) is matched with the positioning hole on the rake arm (71) and fixed by the nut (722). The rake claw (73) corresponding to the large disc (51) is inclined inward. The rake claw (73) corresponding to the small disc (52) is inclined outward.

10. The dehumidification device for hexagonal boron nitride according to claim 9, characterized in that: The bottom of the drying oven (1) is provided with a receiving tray (12), and the receiving tray (12) is provided with a discharge hopper (16); the first rotating shaft (6) is provided with a scraper (17) corresponding to the receiving tray (12).

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