A large-diameter graphite tower for refining phosphoric acid

Abstract

This utility model discloses a large-diameter graphite tower for refining phosphoric acid. It includes a lower reboiler at the bottom and an upper head at the top, with multiple repeating graphite tower sections between the lower reboiler and the upper head. A sealing structure is provided at the connection surface between the upper head, graphite tower sections, and the lower reboiler. The upper head, graphite tower sections, and lower reboiler are fixedly connected by a continuous bolt. The sealing structure includes a concave-convex structure that fits into each other on the connection surface, and a sealing gasket disposed within the concave-convex structure. This utility model's graphite tower features excellent sealing performance and can be made into a large-diameter structure. Furthermore, the sealing structure of this utility model's graphite tower is simple, with minimal increase in cost, and can be widely applied.

Description

Technical Field

[0001] This utility model relates to a graphite tower, and more particularly to a large-diameter graphite tower for refining phosphoric acid. Background Technology

[0002] A graphite tower is a gas-liquid contact mass transfer device made of impermeable graphite material. Due to its good corrosion resistance, heat transfer performance and negative pressure resistance, it is widely used in the extraction method of phosphoric acid production system. It is usually used in chemical operation units such as defluorination, concentration and washing.

[0003] Existing graphite towers are assembled from multiple graphite tower sections, using a modular structure. The seals between the tower sections are generally planar or stepped sealing surfaces. The outer periphery of the graphite tower section is equipped with through bolts. Through the clamping of the upper and lower cover plates and through bolts, the overall tight sealing connection of multiple sealing surfaces between the graphite towers is completed, realizing the combination of multi-layer tower sections.

[0004] Traditional graphite towers used in the refined phosphoric acid industry are generally around 2000mm in diameter. Due to the overly simple sealing structure of traditional graphite tower equipment, the sealing joints between graphite tower sections are prone to leakage after a period of use due to factors such as temperature and corrosion from chemical media. Based on practical experience, the leakage probability at the sealing joints between traditional graphite tower sections is approximately 4%.

[0005] With the rapid development of the battery industry, the demand for refined phosphoric acid is increasing, and the capacity requirements for single production equipment are becoming higher and higher. Due to the limitations of graphite material properties, the difficulty of sealing the tower sections increases exponentially with the increase of tower diameter. When the tower diameter increases to more than 3000mm, the leakage probability at the sealing connection of the graphite tower sections increases to about 10%, which is difficult to completely control, bringing unstable factors to the increase in production capacity. Utility Model Content

[0006] To address the aforementioned technical problems, this invention provides a large-diameter graphite tower for refining phosphoric acid. The graphite tower of this invention features excellent sealing performance and can be manufactured in a large-diameter structure. Furthermore, the sealing structure of the graphite tower of this invention is simple, resulting in minimal cost increase and allowing for widespread application.

[0007] A large-diameter graphite tower for refining phosphoric acid includes a lower reboiler at the bottom and an upper head at the top, with multiple repeating graphite tower sections between the lower reboiler and the upper head.

[0008] A sealing structure is provided at the connection surface between the upper head, the graphite tower section, and the lower tower vessel; the upper head, the graphite tower section, and the lower tower vessel are fixedly connected by a continuous bolt;

[0009] The sealing structure includes a concave-convex structure that fits into each other on the connecting surface, and a sealing gasket disposed in the concave-convex structure.

[0010] This solution improves the sealing performance of the connection surface by setting a concave-convex structure at the connection surface and placing a sealing gasket in the concave-convex structure. At the same time, the entire graphite tower is connected and fixed by a continuous bolt. By using the concave-convex structure design and the continuous bolt connection method, the sealing performance of the connection surface is greatly improved, which allows the graphite tower of this utility model to have a larger diameter.

[0011] Preferably, in the aforementioned large-diameter graphite tower for refining phosphoric acid, the concave-convex structure includes multiple sets of triangular concave-convex surfaces on the inner and outer sides, and a square concave-convex surface in the middle; the sealing gasket in the triangular concave-convex surface is a plate-shaped sealing gasket; and the sealing gasket in the square concave-convex surface is a cylindrical sealing gasket.

[0012] The concave-convex structure of this design consists of triangular concave-convex surfaces on both sides and a square concave-convex surface in the middle. A plate-shaped sealing gasket is set in the triangular concave-convex surface, while a cylindrical sealing gasket is set in the square concave-convex surface. This structure further improves the sealing performance and provides technical support for the large-scale production of graphite towers. Moreover, the structure is simple and the cost increase is minimal.

[0013] Preferably, in the aforementioned large-diameter graphite tower for refining phosphoric acid, the top of the upper end cap is provided with an upper cover plate, and the end edge of the lower tower vessel is provided with a flange. The through bolt passes through the upper cover plate and the flange to fasten the upper end cap, graphite tower section and lower tower vessel.

[0014] The design uses a continuous bolt that runs through the upper cover plate and the flange on the lower tower vessel for connection, resulting in a simple and practical structure.

[0015] Preferably, in the aforementioned large-diameter graphite tower for refining phosphoric acid, flanges are also provided at the end edges of the upper end cap and the graphite tower section. After the through bolt passes through the upper cover plate and the flange, a compression spring is fitted on the through bolt outside the upper cover plate and the flange. A spring cover is provided on the movable end of the compression spring, and a fastening nut is provided on the through bolt outside the spring cover.

[0016] This design incorporates flanges on the upper head and graphite tower sections. Long bolts are then passed sequentially through the upper cover plate and flanges, with a compression spring assembly installed on their outer side. This structure, while ensuring the graphite tower is secured by long bolts, further guarantees the connection strength between each graphite tower section, thereby improving sealing performance. Simultaneously, the compression springs provide pressure compensation during use, overcoming leakage caused by uneven bolt tightening force due to temperature rise, resulting in better sealing stability.

[0017] Preferably, in the aforementioned large-diameter graphite tower for refining phosphoric acid, the lower tower vessel is mounted on a support base.

[0018] Preferably, in the aforementioned large-diameter graphite tower for refining phosphoric acid, the bottom of the lower tower is provided with a material circulation outlet, and the side is provided with a material circulation inlet.

[0019] Preferably, the aforementioned large-diameter graphite tower for refining phosphoric acid has a liquid inlet on the side of the topmost graphite tower section.

[0020] Preferably, in the aforementioned large-diameter graphite tower for refining phosphoric acid, the side of the upper end cap is provided with a gas outlet.

[0021] 1. This solution sets up a concave-convex structure at the connection surface and sets a sealing gasket in the concave-convex structure. At the same time, the entire graphite tower is connected and fixed by a continuous bolt. By using the concave-convex structure design and the continuous bolt connection method, the sealing performance of the connection surface is greatly improved, so that the diameter of the graphite tower of this utility model can be made larger.

[0022] 2. The concave-convex structure of this scheme is divided into triangular concave-convex surfaces on both sides and a square concave-convex surface in the middle. A plate-shaped sealing gasket is set in the triangular concave-convex surface, while a cylindrical sealing gasket is set in the square concave-convex surface. This structure further improves the sealing performance and provides technical support for the large-scale graphite tower; moreover, the structure is simple and the cost increase is small.

[0023] 3. The continuous bolts in this design connect the upper cover plate and the flange on the lower tower vessel, making the structure simple and practical.

[0024] 4. This solution involves installing flanges on the upper end cap and graphite tower sections, and then sequentially passing the long bolts through the upper cover plate and flanges, followed by a compression spring assembly on the outside. This structure, while securing the graphite tower with long bolts, further ensures the connection strength between each graphite tower section, thereby further improving sealing performance. Simultaneously, the compression springs provide pressure compensation during use, overcoming leakage caused by uneven tightening force of the long bolts due to temperature rise, resulting in better sealing stability. Attached Figure Description

[0025] Appendix Figure 1 This is a schematic diagram of the overall structure of the graphite tower of this utility model;

[0026] Appendix Figure 2 For the appendix Figure 1 Enlarged view of region L in the image;

[0027] Appendix Figure 3 This is a schematic diagram of the sealing structure of the connection surface of this utility model;

[0028] Explanation of reference numerals in the attached drawings: 1-Lower column, 2-Upper head, 3-Graphite column section, 4-Support base, 5-Material circulation outlet, 6-Material circulation inlet, 7-Gas outlet, 8-Liquid inlet, 9-Upper cover plate, 10-Flange, 11-Continuous bolt, 12-Compression spring, 13-Spring cover, 14-Fastening nut, 15-Triangular concave-convex surface, 16-Plate-shaped gasket, 17-Square concave-convex surface, 18-Cylindrical gasket. Detailed Implementation

[0029] The present invention will be further described below with reference to the embodiments, but this should not be construed as limiting the present invention.

[0030] Embodiments of this utility model

[0031] A large-diameter graphite tower for refining phosphoric acid, as shown in the attached image. Figure 1-3 The invention includes a lower tower 1 located at the bottom and an upper head 2 located at the top, with multiple repeating graphite tower sections 3 provided between the lower tower 1 and the upper head 2.

[0032] A sealing structure is provided at the connection surface between the upper end cap 2, the graphite tower section 3 and the lower tower vessel 1; the upper end cap 2, the graphite tower section 3 and the lower tower vessel 1 are fixedly connected by a through bolt 11;

[0033] The sealing structure includes a concave-convex structure that fits into each other on the connecting surface, and a sealing gasket disposed in the concave-convex structure.

[0034] In this embodiment, the graphite tower is assembled in the same way as traditional graphite towers. First, the lower tower vessel 1 is fixed, and then the graphite tower sections 3 are stacked one by one according to actual production needs. After stacking to the target height, the upper end cap 2 is placed at the top, and then the through bolts 11 are passed through the upper end cap 2, graphite tower sections 3, and lower tower vessel 1 in sequence and tightened to fix them, so that the upper end cap 2, graphite tower sections 3, and lower tower vessel 1 are connected into a whole tower-shaped structure. The graphite tower in this embodiment has a mutually fitting concave-convex structure between each section, which is similar to a tenon and mortise structure. The concave-convex structure can extend the width of the connection surface, thereby extending the sealing area. In addition, the tortuous route forms a maze-like sealing structure, which further improves the sealing performance.

[0035] Further implementation, for example, is attached. Figure 1-3 The concave-convex structure includes multiple sets of triangular concave-convex surfaces 15 on the inner and outer sides, and a square concave-convex surface 17 in the middle; the sealing gasket in the triangular concave-convex surface 15 is a plate-shaped sealing gasket 16; the sealing gasket in the square concave-convex surface 17 is a cylindrical sealing gasket 18.

[0036] In this embodiment, two sets of triangular concave-convex surfaces 15 are provided on the inner and outer sides of the connecting surface. After the plate-shaped sealing gasket 16 is placed on the triangular concave-convex surface 15, under the pressure of the upper and lower surfaces, the plate-shaped sealing gasket 16 bends with the surface of the triangular concave-convex surface 15, so that it fits completely against the triangular concave-convex surface 15. Similarly, during assembly, the cylindrical sealing gasket 18 is placed in the groove of the square concave-convex surface 17. Under the pressure of the upper and lower surfaces, the cylindrical sealing gasket 18 deforms and fills and seals the groove of the connecting surface, thereby achieving a sealing effect. This embodiment, through the combination of triangular concave-convex surface 15, square concave-convex surface 17, and triangular concave-convex surface 15, greatly extends the area of ​​the sealing surface, making the sealing structure more complex and the sealing performance better.

[0037] Further implementation, for example, is attached. Figure 1-3 The upper end cap 2 is provided with an upper cover plate 9 at its top, and the lower tower 1 is provided with a flange 10 at its end edge. The through bolt 11 passes through the upper cover plate 9 and the flange 10 to fasten the upper end cap 2, the graphite tower section 3 and the lower tower 1.

[0038] Further implementation, for example, is attached. Figure 1-3 The upper end cap 2 and the graphite tower section 3 are also provided with flanges 10. After the through bolt 11 passes through the upper cover plate 9 and the flange 10, a compression spring 12 is sleeved on the through bolt 11 on the outside of the upper cover plate 9 and the flange 10. The movable end of the compression spring 12 is provided with a spring cover 13. A fastening nut 14 is provided on the through bolt 11 on the outside of the spring cover 13.

[0039] After the lower tower 1, graphite tower section 3 and upper end cap 2 are assembled, tighten the fastening nuts 14 one by one. The spring cover 13 compresses the compression spring 12 and uses the compression spring 12 to provide compensation force to the flange 10. When the tightening force of the through bolt 11 is uneven due to the temperature rise effect, the compensation force of the compression spring 12 can continue to provide pressure to tighten each section and ensure the stability of the seal.

[0040] Further implementation, for example, is attached. Figure 1-3 The lower tower vessel 1 is mounted on the support base 4. In this embodiment, the support base 4 is a conventional tower base support, used to support the upper tower structure.

[0041] Further implementation, for example, is attached. Figure 1-3 The lower column reactor 1 is provided with a material circulation outlet 5 at the bottom and a material circulation inlet 6 on the side. The material circulation outlet 5 is used to discharge circulating material, and the material circulation inlet 6 is used to feed circulating material. Its working process is consistent with the inlet and outlet of a traditional refined phosphate graphite tower.

[0042] Further implementation, for example, is attached. Figure 1-3The graphite tower section 3 at the top is provided with a liquid inlet 8 on its side. The liquid inlet 8 is used to introduce a solution and allow the solution to flow downwards from the top of the graphite tower section 3.

[0043] Further implementation, for example, is attached. Figure 1-3 The upper end cap 2 has a gas outlet 7 on its side. Gas flows from bottom to top inside the graphite tower section 3, exchanges gas with the falling solution, and is then discharged from the gas outlet 7.

[0044] The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the technical scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be included within the protection scope of the present invention.

Claims

1. A large-diameter graphite tower for refining phosphoric acid, characterized in that: It includes a lower tower (1) at the bottom and an upper head (2) at the top, with multiple repeating graphite tower sections (3) between the lower tower (1) and the upper head (2). A sealing structure is provided at the connection surface between the upper head (2), the graphite tower section (3) and the lower tower (1); the upper head (2), the graphite tower section (3) and the lower tower (1) are fixedly connected by a through bolt (11); The sealing structure includes a concave-convex structure that fits into each other on the connecting surface, and a sealing gasket disposed in the concave-convex structure.

2. The large-diameter graphite tower for refining phosphoric acid according to claim 1, characterized in that: The concave-convex structure includes multiple sets of triangular concave-convex surfaces (15) on the inner and outer sides, and a square concave-convex surface (17) in the middle; the sealing gasket in the triangular concave-convex surface (15) is a plate-shaped sealing gasket (16); the sealing gasket in the square concave-convex surface (17) is a cylindrical sealing gasket (18).

3. The large-diameter graphite tower for refining phosphoric acid according to claim 1, characterized in that: The top of the upper head (2) is provided with an upper cover plate (9), and the end edge of the lower tower (1) is provided with a flange (10). The through bolt (11) passes through the upper cover plate (9) and the flange (10) to fasten the upper head (2), the graphite tower section (3) and the lower tower (1).

4. The large-diameter graphite tower for refining phosphoric acid according to claim 3, characterized in that: Flanges (10) are also provided at the end edges of the upper end cap (2) and the graphite tower section (3). After the through bolt (11) passes through the upper cover plate (9) and the flange (10), a compression spring (12) is fitted on the through bolt (11) on the outside of the upper cover plate (9) and the flange (10). A spring cover (13) is provided on the movable end of the compression spring (12). A fastening nut (14) is provided on the through bolt (11) on the outside of the spring cover (13).

5. The large-diameter graphite tower for refining phosphoric acid according to claim 1, characterized in that: The lower tower (1) is mounted on the support base (4).

6. The large-diameter graphite tower for refining phosphoric acid according to claim 1, characterized in that: The bottom of the lower tower (1) is provided with a material circulation outlet (5) and the side is provided with a material circulation inlet (6).

7. The large-diameter graphite tower for refining phosphoric acid according to claim 1, characterized in that: The topmost graphite tower section (3) has a liquid inlet (8) on its side.

8. The large-diameter graphite tower for refining phosphoric acid according to claim 1, characterized in that: The upper end cap (2) has a gas outlet (7) on its side.

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