Phosphoric acid defluorination device

Abstract

The utility model discloses a phosphoric acid defluorination device which comprises a tower body and a disperser, and the tower body is provided with an air inlet and an air outlet; the disperser is arranged in the tower body and located in the middle of the tower body, the top of the disperser is provided with a containing cavity and a liquid inlet communicated with the containing cavity, the liquid inlet is used for introducing acid liquor, and the bottom of the disperser is further provided with a plurality of dispersing channels which are communicated with the containing cavity and the interior of the tower body and are distributed in an array mode; the disperser is further provided with a heat exchange cavity, wherein the heat exchange cavity, the containing cavity and the dispersing channel are arranged at intervals, and the heat exchange cavity is used for introducing steam. The heat exchanger is arranged in the disperser, phosphoric acid is heated in the disperser, the plant area does not need to be occupied, the device is simple, and the investment is relatively reduced.

Description

Technical Field

[0001] This utility model relates to the field of phosphoric acid production equipment technology, specifically to a phosphoric acid defluorination device. Background Technology

[0002] Wet-process phosphoric acid generally uses a dihydrate process, yielding a phosphoric acid concentration of approximately 23-26%, commonly referred to as dilute phosphoric acid. This dilute phosphoric acid typically needs further concentration to 47-52%, commonly known as concentrated phosphoric acid. Both dilute and concentrated phosphoric acid have high solids and fluorine content. In the further processing of wet-process phosphoric acid, purification and defluorination are necessary. For example, in the production of refined phosphoric acid and feed calcium salts using wet-process phosphoric acid, defluorination is required. Currently, chemical defluorination or air stripping defluorination is commonly used for wet-process phosphoric acid.

[0003] Patent CN212769877U discloses a wet phosphoric acid defluorination device, comprising a first-effect concentration system consisting of a first-effect heater, a first-effect evaporator, and a first-effect forced circulation pump, a second-effect concentration system consisting of a second-effect heater, a second-effect evaporator, and a second-effect forced circulation pump, and a defluorination tower. The first solution outlet of the first-effect evaporator is connected to the solution inlet of the second-effect heater, the first solution outlet of the second-effect evaporator is connected to the solution inlet of the defluorination tower via a first concentrated phosphoric acid pump, and the first solution outlet and the second solution outlet of the defluorination tower are connected to a second concentrated phosphoric acid pump.

[0004] The aforementioned existing technology involves installing a heat exchanger outside the defluorination tower. Acid is pumped into the heat exchanger for heating. Because the heat exchanger is located outside the defluorination tower, the overall equipment occupies a large plant area and has a high investment cost. Utility Model Content

[0005] The purpose of this utility model is to overcome the above-mentioned technical deficiencies and propose a phosphoric acid defluorination device to solve the technical problems of the existing technology, which requires a large plant area and has high investment costs.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0007] This utility model provides a phosphoric acid defluorination device, comprising:

[0008] The tower body, wherein the tower body is provided with an air inlet and an exhaust outlet; and

[0009] A disperser is disposed inside the tower body and located in the middle of the tower body. The top of the disperser has a receiving cavity and a liquid inlet communicating with the receiving cavity. The liquid inlet is used to introduce acid solution. The bottom of the disperser is also provided with a plurality of dispersion channels communicating with the receiving cavity and the interior of the tower body in an array. The disperser is also provided with a heat exchange cavity spaced apart from the receiving cavity and the dispersion channels. The heat exchange cavity is used to introduce steam.

[0010] In some embodiments, the heat exchange chamber is divided into multiple heat exchange compartments at intervals along the direction from the air inlet to the exhaust outlet, and the multiple heat exchange compartments are connected end to end so that steam passes through the multiple heat exchange compartments sequentially.

[0011] In some embodiments, the disperser is adapted to the tower body to divide the space inside the tower body into a first chamber and a second chamber, the first chamber being connected to the exhaust port and the second chamber being connected to the air inlet. The disperser is also provided with a steam channel that connects the first chamber and the second chamber, and the steam channel is spaced apart from the receiving cavity, the dispersion channel and the heat exchange cavity.

[0012] In some embodiments, the steam channels are provided in multiple ways, and the multiple steam channels are arranged in an array, with their diameter being larger than the diameter of the dispersed channels.

[0013] In some embodiments, the disperser further includes a steam inlet and a steam outlet communicating with the heat exchange chamber, the steam inlet being connected to a steam generator and the steam outlet being connected to the air inlet.

[0014] In some embodiments, the phosphoric acid defluorination device further includes a dispersion component disposed within the tower body and below the disperser, the dispersion component being connected to the air inlet for uniformly dispersing steam within the tower body.

[0015] In some embodiments, the dispersing component has a plurality of upwardly facing dispersing holes, and the plurality of dispersing holes correspond one-to-one with the plurality of dispersing channels.

[0016] In some embodiments, the dispersion component includes a main pipe and a plurality of branch pipes. One end of the main pipe is connected to the air inlet. The plurality of branch pipes are divided into two groups and installed on opposite sides of the main pipe. The branch pipes on the same side are arranged at intervals along the axial direction of the main pipe. One end of each branch pipe is connected to the main pipe, and the other end is blocked. The dispersion holes are provided on the upper side of both the main pipe and the branch pipes.

[0017] In some embodiments, a liquid storage area is formed at the bottom of the tower body, the liquid storage area is used to contain the acid liquid flowing out of the dispersion channel, and the dispersion component is disposed in the liquid storage area.

[0018] In some embodiments, the phosphoric acid defluorination device further includes a circulation pump, which is connected to the storage area and the inlet, respectively, and is used to transport the acid in the storage area to the receiving cavity.

[0019] Compared with the prior art, the phosphoric acid defluorination device provided by this utility model has an air inlet for introducing air or steam into the tower body, with the air or steam flowing from bottom to top. The disperser is arranged in the tower body, and the liquid inlet is connected to an acid supply device to deliver phosphoric acid into the containment cavity. The dispersion channel is used to uniformly disperse the phosphoric acid in the containment cavity and transport it into the tower body, so that the phosphoric acid flows from top to bottom and comes into countercurrent contact with air or steam. Different forms of fluorine in the acid react with the defluorinating agent to generate silicon tetrafluoride gas, which is carried away by the air, thereby achieving the purpose of removing fluorine from the phosphoric acid. Steam is introduced into the heat exchange cavity. Due to the high temperature of the steam, the steam in the heat exchange cavity can exchange heat with the phosphoric acid in the dispersion channel, thereby achieving the purpose of heating the phosphoric acid. This application heats the phosphoric acid by setting a heat exchanger in the disperser, without occupying factory space, simplifying the device and reducing investment.

[0020] The above description is merely an overview of the technical solution of this utility model. To better understand the technical means of this utility model and to enable its implementation according to the description, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. Specific implementation methods of this utility model are given in detail in the following embodiments and their accompanying drawings. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of an embodiment of the phosphoric acid defluorination device provided by this utility model;

[0022] Figure 2 yes Figure 1 Front sectional view of the diffuser;

[0023] Figure 3 yes Figure 1 Partial cross-sectional view of the diffuser;

[0024] Figure 4 yes Figure 1 Top sectional view of the diffuser;

[0025] Figure 5 yes Figure 1 A three-dimensional schematic diagram of the dispersion component.

[0026] Explanation of reference numerals in the attached figures:

[0027] 1-Tower body, 11-Exhaust port, 12-Air inlet, 13-First chamber, 14-Second chamber, 2-Disperser, 21-Shell, 211-Containing cavity, 212-Liquid inlet, 213-Dispersion channel, 214-Heat exchange chamber, 2141-Heat exchange chamber, 215-Steam channel, 216-Steam inlet, 217-Steam outlet, 22-First baffle, 23-Dispersion pipe, 24-Second baffle, 25-Steam pipe, 3-Dispersion assembly, 31-Main pipe, 32-Branch pipe, 4-Circulation pump. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0029] To address the technical problems of existing equipment occupying a large factory area and incurring high investment costs, this utility model provides a phosphoric acid defluorination device. By installing a heat exchanger inside the disperser, phosphoric acid is heated within the disperser, eliminating the need for factory space, simplifying the device, and relatively reducing investment.

[0030] Please see Figure 1 , Figure 1 This is a schematic diagram of the phosphoric acid defluorination device in one embodiment of the present invention.

[0031] This utility model provides a phosphoric acid defluorination device, including a tower body 1 and a disperser 2. The tower body 1 is provided with an air inlet 12 and an exhaust outlet 11. The disperser 2 is located inside the tower body 1 and in the middle of the tower body 1. The top of the disperser 2 has a receiving cavity 211 and a liquid inlet 212 communicating with the receiving cavity 211. The liquid inlet 212 is used to introduce acid solution. The bottom of the disperser 2 is also provided with a plurality of dispersion channels 213 communicating with the receiving cavity 211 and the interior of the tower body 1 in an array. The disperser 2 is also provided with a heat exchange cavity 214 spaced apart from the receiving cavity 211 and the dispersion channels 213. The heat exchange cavity 214 is used to introduce steam.

[0032] In this embodiment, please refer to Figures 1 to 3The air inlet 12 is used to introduce air or steam into the tower body 1. The air or steam flows from bottom to top. The disperser 2 is arranged inside the tower body 1. The liquid inlet 212 is connected to the acid supply device to deliver phosphoric acid into the receiving cavity 211 through the acid supply device. The dispersion channel 213 is used to uniformly disperse the phosphoric acid in the receiving cavity 211 and deliver it into the tower body 1, so that the phosphoric acid flows from top to bottom and comes into countercurrent contact with the air or steam. Different forms of fluorine in the acid react with the defluorinating agent to generate silicon tetrafluoride gas, which is carried away by the air, thereby achieving the purpose of removing fluorine from the phosphoric acid. Steam is introduced into the heat exchange cavity 214. Due to the high temperature of the steam, the steam in the heat exchange cavity 214 can exchange heat with the phosphoric acid in the dispersion channel 213, thereby achieving the purpose of heating the phosphoric acid. This application sets a heat exchanger in the disperser 2 to heat the phosphoric acid in the disperser 2, which does not require the use of factory space, simplifying the equipment and reducing investment.

[0033] The specific locations of the air inlet 12 and the exhaust outlet 11 are not limited. In this embodiment, the air inlet 12 is located at the bottom of the tower body 1, and the exhaust outlet 11 is located at the top of the tower body 1.

[0034] In this embodiment, please refer to Figures 2 to 4 The disperser 2 includes a housing 21, a first partition 22, and a plurality of dispersion tubes 23. The housing 21 is installed inside the tower body 1. The first partition 22 is disposed inside the housing 21 to divide the space inside the housing 21 into a first cavity and a second cavity spaced apart along the direction from the air inlet 12 to the exhaust outlet 11. The first cavity is located above the second cavity and constitutes the receiving cavity 211. The plurality of dispersion tubes 23 are arranged in an array in the second cavity, and the two ends of the dispersion tubes 23 are respectively connected to the first partition 22 and the bottom of the housing 21, thereby connecting the receiving cavity 211 and the space inside the tower body 1. The interior of the dispersion tubes 23 constitutes the dispersion channel 213, and the remaining part of the second cavity constitutes the heat exchange cavity 214.

[0035] In this embodiment, please refer to Figures 2 to 3 The heat exchange chamber 214 is divided into multiple heat exchange chambers 2141 at intervals along the direction from the air inlet to the exhaust outlet. The multiple heat exchange chambers 2141 are connected end to end so that steam passes through the multiple heat exchange chambers 2141 in sequence.

[0036] Specifically, to improve heat exchange efficiency, the disperser 2 further includes multiple second partitions 24. These second partitions 24 are spaced apart within the heat exchange chamber 214 along the direction from the air inlet 12 to the exhaust outlet 11, thereby dividing the heat exchange chamber 214 into multiple heat exchange cells 2141. In two adjacent second partitions 24, one end has a through hole and the other end has a through hole, thereby connecting the multiple heat exchange cells 2141 sequentially along the gas flow direction. This arrangement can extend the residence time of steam in the heat exchange chamber 214 and increase the heat exchange area, thereby improving the heat exchange efficiency between steam and phosphoric acid and ensuring that the phosphoric acid can reach the set temperature.

[0037] In this embodiment, please refer to Figure 1 The disperser 2 is adapted to the tower body 1 to divide the space inside the tower body 1 into a first chamber 13 and a second chamber 14. The first chamber 13 is connected to the exhaust port 11, and the second chamber 14 is connected to the air inlet 12. The disperser 2 is also provided with a steam channel 215, which connects the first chamber 13 and the second chamber 14. The steam channel 215 is spaced apart from the receiving cavity 211, the dispersion channel 213 and the heat exchange cavity 214.

[0038] Specifically, in order to improve heat exchange efficiency, the volume of the disperser 2 needs to be increased as much as possible. Therefore, the diameter of the disperser 2 can be set to match the inner diameter of the tower body 1. Although this increases the volume of the disperser 2, it also divides the space inside the tower body 1 into a first chamber 13 and a second chamber 14, causing gas to be unable to flow from the air inlet 12 to the exhaust port 11. Therefore, a steam channel 215 needs to be provided in the disperser 2 to connect the first chamber 13 and the second chamber 14. The steam channel 215 is not connected to the receiving cavity 211, the dispersion channel 213, and the heat exchange cavity 214.

[0039] Furthermore, the disperser 2 also includes a steam pipe 25, which is inserted into the housing 21 and its two ends are connected to the top and bottom of the housing 21, thereby achieving the purpose of connecting the first chamber 13 and the second chamber 14. The space inside the steam pipe 25 constitutes the steam channel 215.

[0040] In this embodiment, please refer to Figure 4 The steam channel 215 is provided in multiple ways, and the multiple steam channels 215 are arranged in an array, and their diameter is larger than the diameter of the dispersion channel 213.

[0041] Specifically, in order to increase the steam flow rate in the steam channel 215 without affecting the heat exchange between phosphoric acid and the steam in the heat exchange chamber 214, multiple steam pipes 25 are provided, and the multiple steam pipes 25 are evenly distributed throughout the entire shell 21.

[0042] In another embodiment, the cross-sectional area of ​​the disperser 2 is smaller than that of the tower body 1, so that there is a gap between the disperser 2 and the side wall of the tower body 1, which allows gas to pass through, thereby ensuring that the gas can be discharged from the exhaust port 11.

[0043] Specifically, the diameter of the disperser 2 is smaller than the diameter of the tower body 1. The disperser 2 is installed on the side wall of the tower body 1 by a bracket, so that the disperser 2 is spaced apart from the side wall of the tower body 1. There is a gap between the disperser 2 and the side wall of the tower body 1 to connect the first chamber 13 and the second chamber 14, thereby ensuring smooth steam flow.

[0044] In this embodiment, please refer to Figure 2 The disperser 2 is also provided with a steam inlet 216 and a steam outlet 217 that connect to the heat exchange chamber 214. The steam inlet 216 is used to connect to the steam generator, and the steam outlet 217 is connected to the air inlet 12.

[0045] Specifically, the steam inlet 216 and the steam outlet 217 are located on opposite sides of the housing 21. The steam generated by the steam generator first enters the heat exchange chamber 214 to exchange heat with phosphoric acid, and then enters the second chamber 14 through the air inlet 12. It then comes into contact with the phosphoric acid flowing out from the dispersion channel 213 to complete the defluorination. This arrangement can improve the utilization rate of steam.

[0046] In this embodiment, please refer to Figure 1 The phosphoric acid defluorination device further includes a dispersion component 3, which is disposed inside the tower body 1 and located below the disperser 2. The dispersion component 3 is connected to the air inlet 12 and is used to uniformly disperse steam inside the tower body 1.

[0047] Specifically, in order to increase the contact area between the steam entering the second chamber 14 and phosphoric acid, a dispersion component 3 is also provided at the bottom of the tower body 1. The dispersion component 3 is connected to the air inlet 12, so that steam can be introduced into the dispersion component 3. The dispersion component 3 can evenly disperse the steam in all parts of the second chamber 14, thereby increasing the contact area with phosphoric acid and improving the reaction rate.

[0048] In this embodiment, the dispersing component 3 is provided with a plurality of upward-facing dispersing holes, and the plurality of dispersing holes correspond one-to-one with the plurality of dispersing channels 213.

[0049] Specifically, the steam flows from bottom to top, while the phosphoric acid drips downward from the dispersion channel 213. Multiple dispersion channels 213 are provided. In order to ensure that the phosphoric acid dripping in each dispersion channel 213 can come into contact with the steam, multiple dispersion holes corresponding to the dispersion channels 213 can be provided on the dispersion component 3. After the steam enters the dispersion component 3, it is discharged from the dispersion holes and comes into contact with the dripping phosphoric acid.

[0050] In this embodiment, please refer to Figure 5 The dispersion component 3 includes a main pipe 31 and multiple branch pipes 32. One end of the main pipe 31 is connected to the air inlet 12. The multiple branch pipes 32 are divided into two groups and installed on opposite sides of the main pipe 31. The branch pipes 32 on the same side are arranged at intervals along the axial direction of the main pipe 31. One end of each branch pipe 32 is connected to the main pipe 31, and the other end is blocked. The dispersion holes are provided on the upper side of both the main pipe 31 and the branch pipes 32.

[0051] Specifically, one end of the main pipe 31 is closed, and the other end is welded to the air inlet 12. The main pipe 31 extends radially along the tower body 1 and is located in the middle of the tower body 1. One end of the branch pipe 32 is welded to the main pipe 31, and the other end is sealed. The extension direction of the branch pipe 32 is perpendicular to the main pipe 31. Steam enters each of the branch pipes 32 from the main pipe 31 and finally exits from the dispersion hole.

[0052] Furthermore, the diameter of the main pipe 31 is larger than the diameter of the branch pipe 32.

[0053] In this embodiment, a liquid storage area is formed at the bottom of the tower body 1. The liquid storage area is used to contain the acid liquid flowing out of the dispersion channel 213, and the dispersion component 3 is disposed in the liquid storage area.

[0054] In this embodiment, please refer to Figure 1 The phosphoric acid defluorination device also includes a circulation pump 4, which is connected to the storage area and the inlet 212 respectively. The circulation pump 4 is used to transport the acid in the storage area to the receiving cavity 211.

[0055] Specifically, the storage area stores defluorinated phosphoric acid, a large portion of which is pumped back into the tower 1 as circulating acid via the circulating pump 4 for defluorination, while the other small portion is sent to the finished acid storage device for storage as finished acid. The defluorination effect is improved by increasing the number of cycles.

[0056] To better understand this utility model, the following is combined with... Figures 1 to 5 The technical solution of this utility model is described in detail below:

[0057] In practical use, the steam generator is started, generating steam and delivering it to the heat exchange chamber 214. The steam then enters the dispersion component 3 through the steam outlet 217. Subsequently, the acid supply device is started, delivering phosphoric acid into the receiving chamber 211. The phosphoric acid is evenly dispersed and delivered into the tower body 1 through the dispersion channel 213, and comes into countercurrent contact with the steam discharged from the dispersion component 3. Different forms of fluorine in the acid react with the defluorinating agent to generate silicon tetrafluoride gas, which is carried away by the steam, thereby achieving the purpose of removing fluorine from the phosphoric acid. Due to the high temperature of the steam, the steam in the heat exchange chamber 214 can exchange heat with the phosphoric acid in the dispersion channel 213, thereby achieving the purpose of heating the phosphoric acid.

[0058] The specific embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any other corresponding changes and modifications made based on the technical concept of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. A phosphoric acid defluorination device, characterized in that, It includes: The tower body is provided with an air inlet and an exhaust outlet; as well as A disperser is disposed inside the tower body and located in the middle of the tower body. The top of the disperser has a receiving cavity and a liquid inlet communicating with the receiving cavity. The liquid inlet is used to introduce acid solution. The bottom of the disperser is also provided with a plurality of dispersion channels communicating with the receiving cavity and the interior of the tower body in an array. The disperser is also provided with a heat exchange cavity spaced apart from the receiving cavity and the dispersion channels. The heat exchange cavity is used to introduce steam.

2. The phosphoric acid defluorination apparatus according to claim 1, characterized in that, The heat exchange chamber is divided into multiple heat exchange compartments at intervals along the direction from the air inlet to the exhaust outlet. The multiple heat exchange compartments are connected end to end so that steam passes through the multiple heat exchange compartments in sequence.

3. The phosphoric acid defluorination device according to claim 1, characterized in that, The disperser is adapted to the tower body to divide the space inside the tower body into a first chamber and a second chamber. The first chamber is connected to the exhaust port, and the second chamber is connected to the air inlet. The disperser is also provided with a steam channel, which connects the first chamber and the second chamber. The steam channel is spaced apart from the receiving chamber, the dispersion channel, and the heat exchange chamber.

4. The phosphoric acid defluorination device according to claim 3, characterized in that, The steam channel is provided in multiple ways, and the multiple steam channels are arranged in an array, with the diameter of the array being larger than the diameter of the dispersed channel.

5. The phosphoric acid defluorination apparatus according to claim 1, characterized in that, The disperser is also provided with a steam inlet and a steam outlet that connect to the heat exchange chamber. The steam inlet is used to connect to a steam generator, and the steam outlet is connected to the air inlet.

6. The phosphoric acid defluorination apparatus according to claim 5, characterized in that, The phosphoric acid defluorination unit also includes a dispersion component, which is disposed in the tower body and located below the disperser. The dispersion component is connected to the air inlet and is used to uniformly disperse steam in the tower body.

7. The phosphoric acid defluorination apparatus according to claim 6, characterized in that, The dispersion component has multiple upward-facing dispersion holes, and each of the multiple dispersion holes corresponds to a multiple of the dispersion channels.

8. The phosphoric acid defluorination apparatus according to claim 7, characterized in that, The dispersion component includes a main pipe and multiple branch pipes. One end of the main pipe is connected to the air inlet. The multiple branch pipes are divided into two groups and installed on opposite sides of the main pipe. The branch pipes on the same side are spaced apart along the axial direction of the main pipe. One end of each branch pipe is connected to the main pipe, and the other end is blocked. The dispersion holes are provided on the upper side of both the main pipe and the branch pipes.

9. The phosphoric acid defluorination apparatus according to claim 6, characterized in that, A liquid storage area is formed at the bottom of the tower body, which is used to contain the acid liquid flowing out of the dispersion channel, and the dispersion component is located in the liquid storage area.

10. The phosphoric acid defluorination apparatus according to claim 9, characterized in that, The phosphoric acid defluorination device also includes a circulation pump, which is connected to the storage area and the inlet, and is used to transport the acid in the storage area to the receiving cavity.

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