Fixing device for platinum rhodium net of ammonia oxidation furnace for nitric acid preparation

Abstract

This utility model discloses a platinum-rhodium mesh fixing device for an ammonia oxidation furnace in nitric acid preparation, aiming to solve the problem in the prior art where the orderly arrangement of the mesh openings in the platinum-rhodium mesh structure leads to gas rapidly passing through the mesh without effectively contacting the catalytic surface. It includes a fixing bracket for fixing inside the ammonia oxidation furnace. The inner wall of the fixing bracket is arc-shaped, and at least two eccentric positioning rings are rotatably arranged on the arc-shaped surface inside the fixing bracket. These eccentric positioning rings are distributed along the vertical direction of the fixing bracket, and the interior of each eccentric positioning ring has an arc-shaped mounting groove in which the catalytic platinum-rhodium mesh structure is installed. This utility model allows for flexible repositioning and adjustment of the platinum-rhodium mesh catalytic structure in the ammonia oxidation furnace. The structure and adjustment method are simple, helping to keep the mesh openings of different platinum-rhodium meshes in a disordered and random state, thereby increasing the degree of gas turbulence and thus improving the catalytic reaction efficiency.

Description

Technical Field

[0001] This utility model relates to a platinum-rhodium mesh fixing device for an ammonia oxidation furnace used in nitric acid preparation, and belongs to the technical field of nitric acid preparation equipment. Background Technology

[0002] In the process of preparing nitric acid, ammonia gas needs to be reacted with oxygen in an ammonia oxidizer to produce products such as nitric oxide and nitrogen dioxide. The ammonia oxidizer is a device that catalytically reacts ammonia gas with oxygen in the air to produce nitrogen oxides. It is mainly conical in shape, with a porous gas distribution plate installed at the top of the inner cavity, a platinum-rhodium mesh placed in the middle, and a steam superheater pipe at the bottom. Then, the mixture of ammonia gas and air enters from the top and generates nitrogen oxides under the catalytic action of the platinum-rhodium mesh. The excess heat generated is sent to the waste heat boiler through the steam superheater pipe. During the operation of the ammonia oxidizer, the platinum-rhodium mesh is the main catalytic component and plays an important role in the conversion rate of ammonia and the production efficiency and quality of nitrogen oxides.

[0003] In the operation of an ammonia oxidation furnace, multiple layers of platinum-rhodium mesh are usually set to enhance the catalytic reaction effect. However, the design of multiple layers of platinum-rhodium mesh is prone to mesh hole alignment during installation. This setting will cause the airflow to pass through the mesh hole quickly, thereby reducing the actual catalytic reaction time. If square mounting blocks are used to adjust the position of the square mesh holes during installation, if the mesh structure is not uniform, it will also cause the airflow to pass through the mesh hole quickly. The traditional method of adjusting the position of platinum-rhodium mesh using screws and other adjustment methods is cumbersome and has many abrupt points in the structural design. Therefore, a simpler method is needed to disrupt the alignment of the mesh holes, thereby improving the turbulence effect and enhancing the catalytic reaction efficiency. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a platinum-rhodium mesh fixing device for an ammonia oxidation furnace in nitric acid preparation. This device allows for flexible positional adjustment of the platinum-rhodium mesh catalytic structure within the furnace. The structure and adjustment method are simple, and it helps to keep the mesh openings of different platinum-rhodium meshes in a disordered and random state, thereby increasing the degree of gas turbulence and thus improving the efficiency of the catalytic reaction.

[0005] To achieve the above objectives, this utility model employs the following technical solution:

[0006] This utility model provides a platinum-rhodium mesh fixing device for an ammonia oxidation furnace used in nitric acid preparation. It includes a fixing bracket for fixing inside the ammonia oxidation furnace. The inner wall of the fixing bracket is arc-shaped, and at least two eccentric positioning rings are rotatably arranged on the arc-shaped surface inside the fixing bracket. These eccentric positioning rings are distributed along the vertical direction of the fixing bracket. Each eccentric positioning ring has an arc-shaped mounting groove inside, the center of which is not concentric with the arc-shaped surface of the inner wall of the fixing bracket. A platinum-rhodium mesh structure for catalysis is installed in the arc-shaped mounting groove. An adjustment device is provided on one side of the fixing bracket to adjust the rotation angle of the eccentric positioning rings.

[0007] Specifically, the outer side of the fixed bracket is provided with an adjustment groove for exposing the eccentric positioning ring, and the height range of the adjustment groove is within the height range of the corresponding eccentric positioning ring.

[0008] Specifically, the eccentric positioning ring has a hollow internal structure, and multiple positioning holes are arranged at equal intervals along its circumference on the outer side of the eccentric positioning ring. A positioning pin for positioning the eccentric positioning ring is provided at the position of the adjusting groove.

[0009] Specifically, the fixed bracket is also provided with a snap-fit ​​groove at the position of the adjustment groove, and the snap-fit ​​groove is used to position the exposed end of the corresponding positioning pin.

[0010] Specifically, the fixed bracket also has multiple arc-shaped support plates installed inside, which can simultaneously support the eccentric positioning ring and the platinum-rhodium mesh structure.

[0011] Specifically, the outer mounting surface of the fixed bracket is an arc surface, and multiple mounting and positioning blocks are installed at equal intervals in a circular array on the outer side of the fixed bracket.

[0012] Specifically, it also includes a sealing gasket, which is used to fill the space between the outer wall of the fixed bracket and the inner wall of the ammonia oxidation furnace at the upper position of the fixed bracket.

[0013] Compared with the prior art, the beneficial effects achieved by this utility model are as follows:

[0014] This invention utilizes a fixed support with eccentric positioning rings for mounting a platinum-rhodium mesh catalytic structure. This allows different platinum-rhodium meshes to undergo eccentric movement in the horizontal direction. By adjusting the eccentricity, the mesh openings are misaligned, thereby altering the flow state of the airflow in the center of the mesh. This makes it easier for the airflow to contact the catalyst surface, thus improving the catalytic reaction efficiency. The structure provided by this invention offers a simpler way to adjust the turbulence state, allowing for multi-directional angle adjustment based on the cross-sectional effect. It can be quickly and easily adjusted to a more ideal turbulence position. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the platinum-rhodium mesh fixing device provided in this embodiment of the utility model;

[0016] Figure 2 This is an exploded view of the layout of the platinum-rhodium mesh fixing device provided in this embodiment of the utility model;

[0017] Figure 3 This is a front view of the platinum-rhodium mesh fixing device provided in this embodiment of the utility model;

[0018] Figure 4 This is a utility model Figure 3 A cross-sectional view of the platinum-rhodium mesh fixing device provided in the embodiment, along the AA direction;

[0019] Figure 5 This is a utility model Figure 4 Enlarged view of section B of the platinum-rhodium mesh fixing device provided in the embodiment;

[0020] Figure 6 This is a top view of the platinum-rhodium mesh fixing device provided in this embodiment of the utility model;

[0021] Reference numerals in the attached drawings: 1. Fixed bracket; 2. Arc-shaped support plate; 3. Eccentric positioning ring; 4. Platinum-rhodium mesh structure; 5. Adjustment groove; 6. Positioning block; 7. Sealing gasket. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0023] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0024] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Example:

[0025] This utility model provides a platinum-rhodium mesh fixing device for an ammonia oxidation furnace in nitric acid preparation. It allows for flexible repositioning and adjustment of the platinum-rhodium mesh catalytic structure within the furnace. The device is simple in structure and adjustment method, helping to maintain a disordered and randomized state of the mesh openings of different platinum-rhodium meshes, thereby increasing the degree of gas turbulence and improving catalytic reaction efficiency. To achieve the device's structural function, it includes a fixing bracket 1 for fixing inside the ammonia oxidation furnace. The inner wall of the fixing bracket 1 is arc-shaped, and at least two eccentric positioning rings 3 are rotatably mounted on this arc-shaped surface. The outer sides of the eccentric positioning rings 3 rotatably engage with the arc-shaped surface of the inner wall of the fixing bracket 1. The eccentric positioning rings 3 have arc-shaped mounting grooves inside, the center of which is not... The eccentric positioning ring 3 is concentric with the arc surface of the inner wall of the fixed bracket 1 and is installed in the arc-shaped mounting groove. With this arrangement, when the eccentric positioning ring 3 deflects relative to the fixed bracket 1, it can drive the platinum-rhodium mesh structure 4 to be misaligned in the horizontal direction and deflected at an angle. This avoids the lack of high disorder in the adjustment result of large-angle concentric deflection, thereby helping to increase the complexity of gas flow and increase the contact performance with the platinum-rhodium mesh structure 4. At this time, the multiple eccentric positioning rings 3 should be distributed along the vertical direction of the fixed bracket 1. In order to facilitate the adjustment of the angle of the eccentric positioning ring 3, an adjustment device is provided on one side of the fixed bracket 1. This adjustment device is used to adjust the rotation angle of the eccentric positioning ring 3. The specific structure is not limited here.

[0026] This utility model provides a platinum-rhodium mesh fixing device for an ammonia oxidation furnace used in nitric acid preparation. To facilitate the adjustment of the distribution of the platinum-rhodium mesh structure 4 after multiple layers are installed, considering the sealing design of the structure, it is preferable to adjust it indirectly by acting on the platinum-rhodium mesh structure 4 from the outside. Preferably, an adjustment groove 5 for exposing the eccentric positioning ring 3 is provided on the outside of the fixing bracket 1, and the height range of the adjustment groove 5 is set within the height range of the corresponding eccentric positioning ring 3. That is, the adjustment groove 5 is only used to expose part of the wall surface of the eccentric positioning ring 3. External force can pass through the adjustment groove 5 and act directly on the wall surface of the eccentric positioning ring 3 to achieve the overall rotation of the eccentric positioning ring 3 without affecting the normal gas passage effect.

[0027] This utility model provides a platinum-rhodium mesh fixing device for an ammonia oxidation furnace used in nitric acid preparation. To improve the application performance of the eccentric positioning ring 3, the interior of the eccentric positioning ring 3 can be hollow, which can effectively reduce the overall mass of the ring. To facilitate the limiting and fixing of the eccentric positioning ring 3 at a specific angle, multiple positioning holes can be arranged at equal intervals along its circumference on the outer side of the eccentric positioning ring 3. By providing a positioning pin (not shown in the figure) for positioning the eccentric positioning ring 3 at the position of the adjustment groove 5, the eccentric positioning ring 3 can be positioned at a specific position after adjustment. The method of using positioning holes is only one way. As another preferred method, multiple planes can be set on the wall surface of the eccentric positioning ring 3, and the angle of the eccentric positioning ring 3 can be fixed by limiting the angle of the planes with bolts or other structures. Other extension methods are not further limited here.

[0028] This utility model provides a platinum-rhodium mesh fixing device for an ammonia oxidation furnace used in nitric acid preparation. For convenient positioning, when using a pin (the aforementioned positioning pin) structure to limit the angle of the eccentric positioning ring 3, it is also necessary to consider that the position of the pin itself will not shift. Therefore, a snap-fit ​​groove (not shown in the figure) can be provided on the fixing bracket 1 at the position of the adjustment groove 5. The snap-fit ​​groove is used to position the exposed end of the positioning pin. By limiting the exposed end to ensure that the position of the pin itself will not swing, the position of the eccentric positioning ring 3 will not easily swing.

[0029] This utility model provides a platinum-rhodium mesh fixing device for an ammonia oxidation furnace used in nitric acid preparation, such as... Figure 5 As shown, in order to ensure the stability of the eccentric positioning ring 3 and the platinum-rhodium mesh structure 4 in the vertical height direction, multiple arc-shaped support plates 2 are installed inside the fixed bracket 1. The arc-shaped support plates 2 are designed to support the eccentric positioning ring 3 and the platinum-rhodium mesh structure 4 at the same time. The bearing effect reduces the friction pressure required for rotational engagement, and the large bearings that need to be configured on the outside can be omitted to maintain the rotation of the eccentric positioning ring 3.

[0030] This utility model provides a platinum-rhodium mesh fixing device for an ammonia oxidation furnace used in nitric acid preparation. To facilitate the fixing of the fixing bracket 1 inside the ammonia oxidation furnace, the outer mounting surface of the fixing bracket 1 is designed as an arc surface to match the inner wall structure of the furnace. Multiple mounting positioning blocks 6 are evenly spaced and arranged in a circular array on the outer side of the fixing bracket 1, connecting it to the inner wall of the furnace. In a preferred embodiment, the fixing bracket 1 can also be constructed using a spliced ​​structure, facilitating the installation and assembly of the eccentric positioning ring 3 and the platinum-rhodium mesh structure 4.

[0031] This utility model provides a platinum-rhodium mesh fixing device for an ammonia oxidation furnace used in nitric acid preparation. When using the outer mounting positioning block 6 for installation, it is necessary to consider preventing gas leakage from the outside of the fixing bracket 1 to avoid affecting the catalyst's efficiency. To avoid this, the device also includes a sealing gasket 7. Specifically, the sealing gasket 7 fills the space between the outer wall of the fixing bracket 1 and the inner wall of the ammonia oxidation furnace at the upper position of the fixing bracket 1. The sealing gasket 7 can be an aluminum silicate fiber gasket or a combination with an elastic layer to ensure effective contact with the inner wall of the ammonia oxidation furnace.

[0032] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A fixing device for a platinum-rhodium mesh of an ammonia oxidation furnace for nitric acid production, characterized in that, The device includes a fixed bracket (1) for fixing inside the ammonia oxidation furnace. The inner wall of the fixed bracket (1) is an arc surface. At least two eccentric positioning rings (3) are rotatably arranged on the arc surface inside the fixed bracket (1). The multiple eccentric positioning rings (3) are distributed along the vertical direction of the fixed bracket (1). The interior of the eccentric positioning ring (3) is provided with an arc-shaped mounting groove. The center of the arc-shaped mounting groove is not concentric with the arc surface of the inner wall of the fixed bracket (1). A catalytic platinum-rhodium mesh structure (4) is installed in the arc-shaped mounting groove. An adjustment device is provided on one side of the fixed bracket (1). The adjustment device is used to adjust the rotation angle of the eccentric positioning ring (3).

2. The fixing device of the platinum rhodium mesh of the ammonia oxidation furnace for nitric acid production according to claim 1, characterized in that, The outer side of the fixed bracket (1) is provided with an adjustment groove (5) for exposing the eccentric positioning ring (3), and the height range of the adjustment groove (5) is within the height range of the corresponding eccentric positioning ring (3).

3. The fixing device of the platinum rhodium mesh of the ammonia oxidation furnace for nitric acid production according to claim 2, characterized in that, The interior of the eccentric positioning ring (3) is hollow. Multiple positioning holes are arranged at equal intervals along the circumference of the outer side of the eccentric positioning ring (3). A positioning pin for positioning the eccentric positioning ring (3) is provided at the position of the adjusting groove (5).

4. The fixing device of the platinum rhodium mesh of the ammonia oxidation furnace for nitric acid production according to claim 3, characterized in that, The fixed bracket (1) is also provided with a snap-fit ​​groove at the position of the adjustment groove (5), and the snap-fit ​​groove is used to position the exposed end of the corresponding positioning pin.

5. The fixing device of the platinum rhodium mesh of the ammonia oxidation furnace for nitric acid production according to claim 1, characterized in that, The fixed bracket (1) is also equipped with multiple arc-shaped support plates (2), which can simultaneously support the eccentric positioning ring (3) and the platinum-rhodium mesh structure (4).

6. The fixing device of the platinum rhodium mesh of the ammonia oxidation furnace for nitric acid production according to claim 1, characterized in that, The outer mounting surface of the fixed bracket (1) is an arc surface, and multiple mounting positioning blocks (6) are installed at equal intervals in a circular array on the outer side of the fixed bracket (1).

7. The fixing device of the platinum rhodium mesh of the ammonia oxidation furnace for nitric acid production according to claim 6, characterized in that, It also includes a sealing gasket (7) for filling the space between the outer wall of the fixed bracket (1) and the inner wall of the ammonia oxidation furnace at the position above the fixed bracket (1).

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