A phosphoric acid defluorination device

Abstract

The utility model relates to a phosphoric acid defluorination device, comprising a box body, a heating box is arranged at the center of the box body, a connecting shaft is arranged at the center of the four side walls of the heating box and is fixedly connected to the inner wall of the box body, and a stirring shaft is rotatably installed at the center of the heating box, the top of the stirring shaft vertically extends upward to the top of the box body, and a stirring motor is also arranged at the top of the box body and is transmission-connected to the end of the stirring shaft; an exhaust pipe is also arranged on the top of the box body, the other end of the exhaust pipe is connected to a collecting box, and an exhaust fan is also arranged at the connection between the collecting box and the exhaust pipe; the application is based on the improvement of the existing steam defluorination equipment, and by combining the stirring and gas injection structures, all the solutions in the box body are always kept in a circulating state, and in the circulation process, all the liquids are in direct contact with the superheated steam at specific points, the fluorine contacts the high-temperature steam more frequently, and the working efficiency of the defluorination is effectively accelerated.

Description

Technical Field

[0001] The utility model relates to the technical field of defluorination equipment, in particular to a phosphoric acid defluorination device. Background Art

[0002] At present, the dihydrate method is the most widely used method in the world to produce wet-process phosphoric acid, and its output accounts for 80% of the total phosphoric acid in the world. However, the fluorine content of wet-process phosphoric acid produced by this method is too high, so the wet-process phosphoric acid must be defluorinated, which also has the effect of further production and application of phosphoric acid.

[0003] The stripping method is a common method for defluorination of wet phosphoric acid. This method is to inject superheated steam into a container containing phosphoric acid solution, and simultaneously perform vigorous stirring to maintain a certain vacuum degree. The fluorine in the phosphoric acid will be quickly vaporized and pumped away by the vacuum pump along with the water vapor. The existing stirring method mostly uses the rotating stirring of the stirring shaft. The stirring blade rotates in a single direction, and the position of injecting superheated steam is fixed. Therefore, in the actual mixing process, the contact range of the superheated steam is limited, so the defluorination efficiency is low. Utility Model Content

[0004] Based on the above description, the utility model provides a phosphoric acid defluorination device to solve the shortcomings of existing production equipment in which the superheated steam injection position is fixed and the flow direction of the internal liquid driven by the stirring blade is fixed, resulting in a limited contact range of the superheated steam and low defluorination efficiency.

[0005] The utility model is realized through the following technical solutions:

[0006] A phosphoric acid defluorination device comprises a box body, a heating box is provided at the center of the box body, a connecting shaft is provided at the center of each of the four side walls of the heating box and is fixedly connected to the inner wall of the box body, and a stirring shaft is rotatably installed at the center of the heating box, the top end of the stirring shaft vertically extends upward to the top of the box body, a stirring motor is provided at the top of the box body and is transmission-connected to the end of the stirring shaft; an exhaust pipe is also provided at the top of the box body, the other end of the exhaust pipe is connected to a collecting box, and an exhaust fan is also provided at the connection between the collecting box and the exhaust pipe.

[0007] On the basis of the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, the interior of the heating box is hollow and has a number of air holes arranged around the inner wall. At least one of the connecting shafts is hollow and extends to the outer wall of the box body and is provided with a connecting flange. The connecting flange is externally connected to the gas pipe, the other end of the gas pipe is connected to the air pump, and a steam generator is also provided on the air inlet of the air pump.

[0009] Furthermore, a circular hole is provided at the center of the top and bottom surfaces of the heating box, a ball bearing is provided in the circular hole, the stirring shaft is vertically inserted in the center of the ball bearing, and two liquid inlet holes are provided on the top surface of the heating box near the edge of the stirring shaft, and liquid outlet holes are arranged around the periphery of the stirring shaft on the bottom surface of the heating box, and the liquid outlet holes are composed of a plurality of grid-like holes.

[0010] Furthermore, the stirring shaft is sequentially arranged with a guide block, a partition and a stirring blade, wherein the guide block is an inverted cone and is arranged directly above the liquid inlet hole on the top surface of the heating box, the partition is a circular plate and is horizontally arranged at the center of the heating box, and the partition divides the interior of the heating box into two and leaves a gap between its side wall and the inner wall of the heating box, and the stirring blade is arranged at the bottom of the heating box, and the length of the stirring blade can just completely cover the liquid outlet hole on the bottom surface of the heating box.

[0011] Furthermore, the stirring shaft and the interior of the partition are both arranged to be hollow, and the surface of the partition is also arranged with a plurality of spray holes connected to the interior of the partition. The top end of the stirring shaft is connected to an air inlet pipe through a bearing, and the other end of the air inlet pipe is connected to the air supply pipe.

[0012] Furthermore, the gas pipeline is also provided with a temperature sensor and a flow meter.

[0013] Furthermore, a liquid inlet pipe is vertically arranged on one side of the top of the box body, and a liquid discharge pipe is horizontally arranged at the bottom end of the side wall of the box body. Valves are provided on the liquid inlet pipe and the liquid discharge pipe.

[0014] Compared with the prior art, the technical solution of this application has the following beneficial technical effects:

[0015] 1. The present application is based on the improvement of the existing steam defluorination equipment. By combining stirring with gas injection structure, all solutions inside the box are always kept in a circulating state. In the circulation process, all liquids will be in direct contact with superheated steam at specific points. In this structure, the stirring can be made more intense, and the contact between fluorine and high-temperature steam is more frequent, which effectively speeds up the defluorination work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the internal structure of the box in this embodiment;

[0017] Figure 2 This is a schematic diagram of the internal structure of the heating box in this embodiment;

[0018] Among them: 1. Box body; 11. Liquid inlet pipe; 12. Liquid discharge pipe; 13. Valve; 2. Heating box; 21. Connecting shaft; 22. Connecting flange; 23. Liquid inlet hole; 24. Liquid outlet hole; 3. Stirring shaft; 31. Guide block; 32. Partition; 33. Stirring blade; 34. Air inlet pipe; 4. Exhaust pipe; 5. Air pipe; 6. Air pump; 7. Steam generator. DETAILED DESCRIPTION

[0019] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0021] Combination Figure 1 and Figure 2 As shown, a phosphoric acid defluorination device comprises:

[0022] Box 1 is a container for holding phosphoric acid solution. It can be made of metal with a coating added to the inner wall, or directly made of plastic material according to actual use.

[0023] The heating box 2 is arranged inside the box body 1 and is connected and fixed to the inside of the box body 1 through at least four connecting shafts 21. The device is used to reciprocately heat the phosphoric acid inside the box body 1 to increase the gasification rate of the fluorine inside the box body 1;

[0024] The stirring shaft 3 is used to speed up the circulation of the phosphoric acid solution inside the housing 1, thereby enhancing the stirring effect and expanding the contact range of the phosphoric acid;

[0025] The exhaust pipe 4 is used to extract the steam and gasified fluorine inside the box body 1, and its end is connected to the collection box.

[0026] Specifically, the side wall of the heating box 2 is hollow inside and is provided with a connecting shaft 21 on each of its four sides, and is fixed to the inner wall of the box body 1 by means of the connecting shaft 21 to form a support. At the same time, among the four connecting shafts 21, at least one is hollow, and its end extends to the outer wall of the heating box 2 and is provided with a connecting flange 22, which is connected to the external gas pipeline 5 by means of the connecting flange 22, and the other end of the gas pipeline 5 is connected to the air pump 6, and the air inlet of the air pump 6 is connected to the steam generator 7;

[0027] In addition, a plurality of air holes are arranged on the inner wall of the heating box 2. Therefore, when the air pump 6 starts to work, a large amount of high-temperature steam will rush into the air holes and spray into the interior, thereby rapidly increasing the temperature inside the heating box 2, thereby achieving the purpose of rapidly gasifying the fluorine in the phosphoric acid.

[0028] A circular hole is arranged at the center of the top and bottom surfaces of the heating box 2, and a ball bearing is provided at the circular hole. The stirring shaft 3 is vertically inserted in the center of the ball bearing, and liquid inlet holes 23 are arranged on both sides of the top surface of the heating box 2 close to the stirring shaft 3. Liquid outlet holes 24 are arranged around the stirring shaft 3 on the bottom surface of the heating box 2, and the liquid outlet holes 24 are composed of a plurality of grid-like holes.

[0029] The stirring shaft 3 is provided with a guide block 31, a partition 32 and a stirring blade 33 arranged in sequence from top to bottom, wherein the guide block 31 is an inverted cone and is arranged directly above the liquid inlet 23 on the top surface of the heating box 2, the partition 32 is a circular plate and is arranged horizontally at the center of the heating box 2, and the partition 32 divides the interior of the heating box 2 into two and leaves a gap between its side wall and the inner wall of the heating box 2, and the stirring blade 33 is arranged at the bottom of the heating box 2, and the length of the stirring blade 33 can just completely cover the liquid outlet 24 on the bottom surface of the heating box 2.

[0030] Based on the above structure and in combination with the accompanying drawings, it can be seen that when the stirring blade 33 at the bottom rotates, the phosphoric acid solution at the bottom will be squeezed toward the surroundings, thereby forming a negative pressure at the bottom of the heating box 2, extracting the phosphoric acid inside the heating box 2, and the continuously squeezed phosphoric acid liquid level will be higher than the top surface of the heating box 2 and flow back to the inside of the heating box 2 through the liquid inlet hole 23 at its top, thereby forming a circulation structure, ensuring that all phosphoric acid liquid can directly contact the high-temperature steam, and at the same time, the liquid entering the inside of the heating box 2 will be blocked by the partition 32, thereby forming a vortex state, naturally forming a stirring effect, and effectively improving the intensity of stirring based on the overall circulation.

[0031] At the same time, the interior of the stirring shaft 3 and the partition 32 are both hollow and interconnected. A large number of spray holes are arranged on both sides of the partition 32. The top of the stirring shaft 3 is connected to an air inlet pipe 34 through a bearing seat, and the other end of the air inlet pipe 34 is connected to the air supply pipe 5, so that the phosphoric acid inside the heating box 2 is synchronously injected through the partition 32 to further expand the contact range.

[0032] The gas pipe 5 should also be provided with a temperature sensor and a flow meter, which are used to detect the amount and temperature of steam input into the box body 1, so that the staff can make real-time adjustments.

[0033] A liquid inlet pipe 11 and a liquid discharge pipe 12 are respectively disposed at the top and the bottom of the box body 1, and valves 13 are disposed on the liquid inlet pipe 11 and the liquid discharge pipe 12 to ensure that the inside of the box body 1 is in a close to vacuum state during operation.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solution recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solution from the technical solution of the embodiments of the utility model.

Claims

1. A phosphoric acid defluorination device, characterized in that: The invention comprises a box body (1), wherein a heating box (2) is provided at the center of the box body (1), a connecting shaft (21) is provided at the center of each of the four side walls of the heating box (2) and is fixedly connected to the inner wall of the box body (1), and a stirring shaft (3) is rotatably mounted at the center of the heating box (2), the top end of the stirring shaft (3) vertically extending upward to the top end of the box body (1), and a stirring motor is provided at the top end of the box body (1) and is drivingly connected to the end of the stirring shaft (3); an exhaust pipe (4) is also provided at the top of the box body (1), the other end of the exhaust pipe (4) is connected to a collection box, and an exhaust fan is also provided at the connection between the collection box and the exhaust pipe (4).

2. A phosphoric acid defluorination device according to claim 1, characterized in that: The interior of the heating box (2) is hollow and has a plurality of air holes arranged around the inner wall. At least one of the connecting shafts (21) is hollow and extends to the outer wall of the box body (1) and is provided with a connecting flange (22). The connecting flange (22) is externally connected to an air supply pipe (5). The other end of the air supply pipe (5) is connected to an air pump (6), and a steam generator (7) is also provided on the air inlet of the air pump (6).

3. A phosphoric acid defluorination device according to claim 2, characterized in that: A circular hole is provided at the center of the top and bottom surfaces of the heating box (2), a ball bearing is provided in the circular hole, the stirring shaft (3) is vertically inserted into the center of the ball bearing, and two liquid inlet holes (23) are provided on the top surface of the heating box near the edge of the stirring shaft (3), and liquid outlet holes (24) are arranged around the outer periphery of the stirring shaft (3) on the bottom surface of the heating box (2), and the liquid outlet holes (24) are composed of a plurality of grid-like holes.

4. A phosphoric acid defluorination device according to claim 3, characterized in that: The stirring shaft (3) is also provided with a guide block (31), a partition (32) and a stirring blade (33) in sequence, wherein the guide block (31) is in an inverted cone shape and is arranged directly above the liquid inlet hole (23) on the top surface of the heating box (2); the partition (32) is a circular plate and is arranged horizontally at the center of the heating box (2); the partition (32) divides the interior of the heating box (2) into two parts and leaves a gap between its side wall and the inner wall of the heating box (2); the stirring blade (33) is arranged at the bottom of the heating box (2), and the length of the stirring blade (33) is just enough to completely cover the liquid outlet hole (24) on the bottom surface of the heating box (2).

5. A phosphoric acid defluorination device according to claim 4, characterized in that: The interior of the stirring shaft (3) and the partition (32) are both arranged to be hollow, and a plurality of spray holes are arranged on the surface of the partition (32) and are in communication with the interior of the partition (32). The top end of the stirring shaft (3) is connected to an air intake pipe (34) via a bearing, and the other end of the air intake pipe (34) is in communication with the air delivery pipe (5).

6. A phosphoric acid defluorination device according to claim 2, characterized in that: The gas delivery pipe (5) is also provided with a temperature sensor and a flow meter.

7. A phosphoric acid defluorination device according to claim 1, characterized in that: A liquid inlet pipe (11) is vertically arranged on one side of the top of the box body (1), and a liquid discharge pipe (12) is horizontally arranged at the bottom end of the side wall of the box body (1), and valves (13) are provided on both the liquid inlet pipe (11) and the liquid discharge pipe (12).

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