Industrial production of hexagonal boron nitride raw material pre-dehydration oven

Abstract

This utility model discloses an oven for pre-dehydrating raw materials used in the industrial preparation of hexagonal boron nitride, comprising an oven body, a support frame, shelves, a material tray, and a central door pillar. The oven body has doors at both the front and rear, forming a double-door structure. The multi-layer heating tube structure is arranged parallel to the upper and lower surfaces of the oven body. Two central door pillars are symmetrically arranged inside the oven body, adjacent to the front and rear doors respectively. Multiple sets of support frames are provided, each set at the same height. Slides are installed on the shelves, and the material tray is placed on the slides. This utility model provides an oven for pre-dehydrating raw materials used in the industrial preparation of hexagonal boron nitride, with a simple and reasonable structural design, which can significantly improve the gas flow within the oven after application.

Description

Technical Field

[0001] This utility model relates to the field of industrial preparation of hexagonal boron nitride, and specifically provides an oven for pre-dehydration of raw materials for industrial preparation of hexagonal boron nitride. Background Technology

[0002] The industrial preparation of hexagonal boron nitride involves reacting a boron source and a nitrogen source at high temperatures of 1800 °C or above, using graphite as a crucible. Common boron sources such as boric acid and borax remove a significant amount of water during heating. This water reacts with the graphite crucible, reducing its lifespan. Therefore, it is necessary to pre-dehydrate the raw materials for preparing hexagonal boron nitride at 200-300 °C, using an oven as a common equipment.

[0003] Unlike ordinary materials, the raw materials used in the industrial preparation of hexagonal boron nitride not only lose moisture during the pre-dehydration process, but also evaporate along with the moisture, producing a large amount of solid volatiles. These solid volatiles accumulate on the bottom plate of each layer of heating tubes in the oven, forming a hard shell that is difficult to clean. Simultaneously, placing the material trays directly on the shelves blocks many ventilation holes, hindering the flow of moisture and volatiles within the oven. This causes the volatile shell to thicken rapidly, especially in the lower layers of the oven where poor ventilation exacerbates the problem. For certain formulations, the shell thickening rate can reach several millimeters per day, requiring frequent oven shutdowns for cleaning.

[0004] Therefore, providing a novel oven structure suitable for drying raw materials used in the industrial preparation of hexagonal boron nitride is a problem that urgently needs to be solved. Utility Model Content

[0005] Therefore, the purpose of this utility model is to provide an oven for pre-dehydration of raw materials for the industrial preparation of hexagonal boron nitride, so as to significantly improve the ventilation inside the oven and reduce the deposition of raw materials for the preparation of hexagonal boron nitride during the pre-dehydration process.

[0006] The technical solution provided by this utility model is: an oven for pre-dehydrating raw materials for industrial preparation of hexagonal boron nitride, comprising an oven body, a support frame, shelves, a material tray, and a central door column. The oven body has doors on both the front and rear sides, which are double-door structures. Each side of the door has a double-opening structure. The oven body has a multi-layer heating tube structure, which is arranged parallel to the upper and lower surfaces of the oven body. Two central door columns are symmetrically arranged in the center of the oven body, and the two central door columns are adjacent to the front and rear doors, respectively.

[0007] The support frame is provided in multiple sets, with each set of support frames located at the same height. The two sides of the shelf overlap on each set of opposite support frames, and ventilation holes are provided on the shelf. Each layer of the shelf is alternately arranged with each layer of heating pipes, wherein the installation height of each layer of the shelf is higher than the height of each layer of heating pipe structure.

[0008] The shelf is equipped with slide rails, and the material tray is placed on the slide rails. There are multiple slide rails, each of which extends along the depth direction of the oven body and is arranged on the shelf. The installation width between the slide rails is adapted to the width of the material tray, and the material tray is placed on the slide rail.

[0009] Specifically, each set of support frames includes four support frames, namely the first support frame, the second support frame, the third support frame, and the fourth support frame. The first support frame and the second support frame are respectively installed opposite each other on the inner side of the oven wall and extend along the inner side of the oven wall. The third support frame and the fourth support frame are installed on both sides of the two central door pillars, with the first support frame and the third support frame facing each other, and the second support frame and the fourth support frame facing each other.

[0010] Specifically, each of the support frames has an inverted L-shaped cross section. One side of the inverted L-shape is fixed to the inner wall of the oven or the central door post, while the other side is perpendicular to the fixed surface and extends into the oven to support the shelves.

[0011] Specifically, the shelf is a stainless steel plate structure, and the ventilation holes are elongated and evenly distributed on the shelf body.

[0012] Specifically, the slide rail protrudes from the shelf surface.

[0013] This utility model provides an oven for pre-dehydration of hexagonal boron nitride raw materials in industrial production. The oven has a simple and reasonable structural design and can significantly change the gas flow inside the oven after application. Attached Figure Description

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments:

[0015] Figure 1 A schematic diagram of the internal structure of an oven for pre-dehydration of hexagonal boron nitride raw materials for industrial preparation provided by this utility model;

[0016] Figure 2 A schematic diagram of the internal structure of an oven for pre-dehydration of hexagonal boron nitride raw materials for industrial preparation provided by this utility model;

[0017] Figure 3 This utility model provides a top view of the internal structure of an oven for pre-dehydration of hexagonal boron nitride raw materials. Detailed Implementation

[0018] The present invention will be further explained below with reference to specific implementation schemes, but it is not limited to the present invention.

[0019] like Figure 1-2 As shown, this invention provides an oven for pre-dehydrating raw materials used in the industrial preparation of hexagonal boron nitride. The oven includes an oven body, a support frame 1, a shelf 3, a material tray 6, and a central door post 8. The oven body has doors on both the front and rear, forming a double-door structure. Each door is double-opening. The oven body contains a multi-layer heating tube structure 9, which is parallel to the top and bottom surfaces of the oven body. Two central door posts 8 are symmetrically arranged in the center of the oven body, adjacent to the front and rear doors respectively. When the oven doors are closed, the central door posts 8 ensure a snug fit between the double doors and prevent the oven door beams from collapsing. Furthermore, the heating and other circuit structures involved in the oven body described in this invention are all existing technologies and will not be described in detail here.

[0020] The space between the central pillar of the front door and the central pillar of the rear door of the oven serves as a ventilation channel for the oven.

[0021] The support frame 1 is provided in multiple sets, with each set of support frame 1 located at the same height. The two sides of the shelf 3 overlap on each set of opposite support frame 1. The shelf 3 is provided with ventilation holes 4. Each layer of shelf 3 is alternately arranged with each layer of heating pipe, wherein the installation height of each layer of shelf 3 is higher than the height of each layer of heating pipe structure.

[0022] The shelf 3 is equipped with a slide rail 5, and the material tray 6 is placed on the slide rail 5. There are multiple slide rails 5, and each slide rail 5 extends along the depth direction of the oven body and is arranged on the shelf 3. The installation width between the slide rails 5 is adapted to the width of the material tray 6, and the material tray 6 is placed on the slide rail.

[0023] Preferably, each set of support frames 1 includes four support frames, namely a first support frame, a second support frame, a third support frame, and a fourth support frame. The first support frame and the second support frame are respectively installed opposite each other on the inner side of the oven wall and extend along the inner side of the oven wall. The third support frame and the fourth support frame are installed on both sides of the two central door pillars. The first support frame and the third support frame are arranged opposite each other, and the second support frame and the fourth support frame are arranged opposite each other.

[0024] The support frame has an inverted L-shaped cross section, which is compatible with the double-door multi-layer oven. It is installed on the inner wall of the multi-layer oven at a position slightly higher than the heating tubes of each layer.

[0025] Specifically, the support frame installed on the inner wall of the oven extends inward along the inner wall, while the support frame installed at the central door post extends inward a shorter length. There are no major restrictions on the material of the support frame or the connection method with the oven, as long as it does not rust or corrode in a humid environment at 300℃, and the connection has sufficient strength to effectively support the weight of the shelves and the trays filled with materials.

[0026] Specifically, one side of the inverted L-shape is fixed to the inner wall of the oven or the central door post 8, while the other side is perpendicular to the fixed surface and extends into the oven to support the shelf 3.

[0027] The shelf 3 is made of stainless steel plate, and the ventilation holes 4 are elongated and evenly distributed on the shelf body.

[0028] Specifically, shelf 3 has evenly distributed elongated ventilation holes, each with a certain width. The shelf rests on a support frame. For double-door ovens, the shelf is divided into two sides by the central door post, with each side supported by a support frame on the same side of the oven wall and the same side of the central door post, respectively. A relatively wide gap is left between the two sides of the shelf to allow for air circulation inside the oven.

[0029] The shelf can be made from a single piece of board or from more than one piece of stainless steel sheet joined together. The shelf is placed on a support frame.

[0030] The shelf 3 is equipped with slide rails 5, and the tray 6 is placed on the slide rails 5. Multiple slide rails 5 are provided, each extending along the depth of the oven body on the shelf 3. The installation width between the slide rails 5 is adapted to the width of the tray 6. The tray 6 is placed on the slide rail. The slide rails 5 can elevate the tray 6 to a certain height, allowing the tray to move and facilitating material retrieval. The material of the slide rails 5 is the same as that of the shelf 3. The installation position of the slide rails 5 can partially block the ventilation holes 4. The shape of the slide rails 5 should have low sliding resistance and be easily and reliably connected to the shelf 3. Therefore, the preferred cross-sectional shape is a square, semi-circular, or trapezoidal shape with a flat bottom and a flat or curved top surface. For trays 6 made of ceramic, since ceramic is easily damaged, the top surface should be selected with a slightly larger contact area, such as a square or trapezoidal shape.

[0031] During heating, after the material tray 6 is placed in, the top surface of the material will approach the heating tube. The volatiles will rise through the gaps in the heating tube, pass through the shelf 3 through the ventilation hole 4, and move in the heating layer plane of the space formed by the material tray being supported by the slide rail 5. A small portion of the solid volatiles will deposit on the back of the material tray 6, while most of the volatiles will flow to the area behind the central door post 2 that is not covered by the shelf (a relatively wide gap is left between the shelves on both sides). The volatiles will continue to rise, pass through the upper heating tube to the top of the oven, and be discharged by the oven exhaust fan.

[0032] Since the raw materials for industrial preparation of hexagonal boron nitride are not corrosive to the heating tubes, the oven in this embodiment eliminates the bottom plate structure between each layer in existing ovens, preventing material from accumulating on the bottom plate. Long, narrow ventilation holes are provided on the shelves, increasing the ventilation area, and slides are used to lift the trays off the shelves, preventing the trays from blocking the shelves' holes and further improving ventilation. The slides also reduce frictional resistance when placing and removing the trays from the oven, and most solid volatiles deposit on the bottom surface of the trays, which can be carried away by the trays for easy centralized cleaning.

[0033] Example 1:

[0034] This embodiment provides an industrial double-door oven with a heating zone length of 2000 mm, a central doorpost width of 150 mm, and each heating layer height of 200 mm. It is fitted with a material tray with a length of 400 mm, a height of 100 mm, and a width equal to half the oven depth. The bottom end of an inverted L-shaped support frame to be installed on one side of the central doorpost is aligned with the heating pipe on the same plane. The upper end of the inverted L-shaped support frame is approximately 50 mm from the heating pipe and extends approximately 50 mm into the oven. The position of the inverted L-shaped support frame installed on the inner wall of the oven on the same side is adjusted so that its upper end is aligned with the upper end of the central doorpost support frame and extends approximately 50 mm into the oven. A shelf with a length of 900 mm is placed on this side of the support frame. The width of the shelf is the same as the oven thickness. Ventilation holes with a width of 40 mm and a length of 100 mm are cut on the shelf, with a spacing of 40 mm between the holes and a 40 mm gap from the edge. Because the shelf expands and contracts with temperature changes, it is not fixed to the support frame.

[0035] Five square stainless steel slides, each 20 mm high, are installed on the shelf at intervals of 150 mm, starting from the shelf's distance from the inner wall of the oven.

[0036] The same method was used to install oven shelves on the other side of the central gatepost.

[0037] In use, fill the trays with the material to be pre-dehydrated until it is parallel to the top surface of the trays. Place the trays into the heating layer of the oven through the chutes. Perform the pre-dehydration operation. After the operation is complete, slide the trays out of the chutes, unload the material, and remove any sediment from the back of the trays. This completes one operating cycle.

[0038] The specific embodiments of this utility model are written in a progressive manner, emphasizing the differences between each implementation scheme, and the similar parts can be referred to each other.

[0039] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. An oven for pre-dehydration of hexagonal boron nitride raw materials in industrial production, characterized in that, The oven body includes a support frame (1), a shelf (3), a material tray (6), and a central door post (8). The oven body has doors on both the front and rear, which are double doors. Each door is double-opening. The oven body has a multi-layer heating tube structure (9), which is parallel to the top and bottom surfaces of the oven body. The oven body has two central door posts (8) symmetrically arranged in the center, which are adjacent to the front and rear doors respectively. The support frame (1) is provided in multiple sets, each set of support frame (1) is located at the same height, the two sides of the shelf (3) overlap on each set of opposite support frame (1), and the shelf (3) is provided with ventilation holes (4); each layer of shelf (3) is alternately arranged with each layer of heating pipe, wherein the installation height of each layer of shelf (3) is higher than the height of each layer of heating pipe structure; The shelf (3) is equipped with a slide (5), and the tray (6) is placed on the slide (5). There are multiple slides (5), and each slide (5) extends along the depth direction of the oven body and is arranged on the shelf (3). The installation width between the slides (5) is adapted to the width of the tray (6), and the tray (6) is placed on the slide.

2. The drying oven for pre-dehydration of hexagonal boron nitride raw materials according to claim 1, characterized in that, Each set of support frames (1) includes four support frames, namely the first support frame, the second support frame, the third support frame and the fourth support frame. The first support frame and the second support frame are respectively installed opposite each other on the inner side of the oven wall and extend along the inner side of the oven wall. The third support frame and the fourth support frame are installed on both sides of the two central door pillars. The first support frame and the third support frame are arranged opposite each other, and the second support frame and the fourth support frame are arranged opposite each other.

3. The drying oven for pre-dehydration of hexagonal boron nitride raw materials according to claim 1, characterized in that, Each of the support frames (1) has an inverted L-shaped cross section. One side of the inverted L-shape is fixed to the inner wall of the oven or the central door post (8), and the other side is perpendicular to the fixed surface and extends into the oven to support the shelf (3).

4. The drying oven for pre-dehydration of hexagonal boron nitride raw materials according to claim 1, characterized in that, The shelf (3) is made of stainless steel plate, and the ventilation holes (4) are long strips and are evenly distributed on the shelf body.

5. The drying oven for pre-dehydration of hexagonal boron nitride raw materials according to claim 1, characterized in that, The slide (5) protrudes from the surface of the shelf (3).

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