Raw material recovery device for sodium pyrithione production

Abstract

The utility model discloses a raw material recovery device for sodium pyrithione production, which belongs to the technical field of sodium pyrithione production and comprises an acid treater, a gas outlet is arranged at the top of the acid treater and connected with an alkali liquor tower through a first pipeline, a gas outlet end of the first pipeline is positioned below the surface of alkali liquor in the alkali liquor tower, and a partition plate is arranged above the alkali liquor. The partition plate divides the alkali liquor tower into an upper part and a lower part; a first liquid outlet is formed in the partition plate; a spraying assembly is arranged above the partition plate, the spraying assembly is communicated with the lower part of the alkali liquor tower through a circulating pipe, and a hydrogen sulfide detector is arranged below the partition plate; and a fan is arranged on the air return pipe, an alkali liquor inlet is formed in the side wall of the alkali liquor tower, and an alkali liquor outlet is formed in the bottom of the alkali liquor tower. The gas return pipe sucks escaped hydrogen sulfide to the position above the partition plate, the spraying assembly sprays alkali liquor, residual hydrogen sulfide gas is absorbed, the recovery efficiency of hydrogen sulfide is high, and the occupied area of equipment is small.

Description

Technical Field

[0001] This utility model relates to the field of sodium pyridinethione production technology, specifically to a raw material recovery device for sodium pyridinethione production. Background Technology

[0002] Sodium pyrithione (SPT), chemically known as 2-mercaptopyridine-1-oxide sodium salt, is a white or off-white powder in its pure form. Currently, industrially, it is mainly synthesized using 2-chloropyridine or pyridine as raw materials. During the synthesis of sodium pyrithione, an excess of sodium hydrosulfide is usually added to ensure complete conversion of 2-chloropyridine-N-oxide to sodium pyrithione. After the reaction, acidification is used to convert the sodium hydrosulfide to hydrogen sulfide, which is then recovered using an alkaline solution.

[0003] Existing equipment typically uses multiple hydrogen sulfide absorption towers to recover and reuse hydrogen sulfide. However, multiple absorption towers result in a large footprint, high cost, and ineffective recovery and reuse of hydrogen sulfide.

[0004] In view of the problems existing in the prior art, this utility model, combining years of design and use experience in related fields, designs and manufactures a raw material recovery device for the production of sodium pyridinethione to overcome the above defects. Summary of the Invention

[0005] To address the problems existing in the prior art, this utility model provides a raw material recovery device for the production of sodium pyridinethione, which can fully absorb hydrogen sulfide without the need for multiple absorption towers, thereby improving the treatment efficiency of hydrogen sulfide and reducing the equipment footprint.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A raw material recovery device for the production of sodium pyridinethione includes an acid processor. The top of the acid processor is provided with an air outlet. The air outlet is connected to an alkali tower through a first pipe. The air outlet end of the first pipe is located below the surface of the alkali liquid in the alkali tower. A baffle is provided above the alkali liquid, and the baffle divides the alkali tower into upper and lower parts. A first liquid outlet is provided on the baffle.

[0007] A spray assembly is provided above the partition, and the spray assembly is connected to the lower part of the alkali tower through a circulation pipe. A hydrogen sulfide detector is provided below the partition. A return gas pipe is provided at the top of the alkali tower, which connects the area above and below the partition. A fan is provided on the return gas pipe. An alkali inlet is provided on the side wall of the alkali tower, and an alkali outlet is provided at the bottom of the alkali tower.

[0008] Preferably, the spray assembly includes two support rods, which are vertically arranged. The top ends of the two support rods are connected to the top end of the inner wall of the alkali tower. An annular tube is fixed at the bottom end of the two support rods. Several nozzles are distributed circumferentially on the lower surface of the annular tube. The annular tube is connected to the circulation tube.

[0009] Preferably, the outlet end of the first pipe is connected to the bottom of the alkali tower; a rotating shaft is vertically provided inside the alkali tower, the top end of the rotating shaft passes through the partition, the annular pipe, and the top of the alkali tower in sequence and is connected to a first motor, the bottom end of the rotating shaft is rotatably connected to the first pipe, and the lower part of the rotating shaft has a hollow section, which is connected to the first pipe;

[0010] The rotating shaft is provided with a plurality of first stirring rods. The lowest first stirring rod has a hollow structure and is provided with a plurality of air vents. The hollow structure of the first stirring rod is connected to the hollow section and the air vents. The air vents are provided with a waterproof and breathable membrane.

[0011] Preferably, the rotating shaft is rotatably connected to the first pipe via a rotary joint.

[0012] Preferably, the circulation pipe is equipped with a circulation pump and a circulation valve;

[0013] The return air pipe is equipped with a return air valve.

[0014] Preferably, the first pipe is equipped with an air pump.

[0015] Preferably, there are two alkali towers; the first pipeline is connected to a first branch pipe and a second branch pipe respectively through a three-way valve, the three-way valve is close to the output end of the air pump, and the first pipeline is connected to the alkali tower through the first branch pipe and the second branch pipe respectively.

[0016] Preferably, the acid processor has a heating jacket on its outer wall, a liquid inlet and an acid inlet on its top, and a second liquid outlet on its bottom.

[0017] Preferably, the acid processor is provided with a second stirring assembly, the second stirring assembly including a second motor, the second motor being located at the top of the acid processor, the output end of the second motor being connected to a rotating shaft, the rotating shaft being vertically arranged, the lower end of the rotating shaft passing through the top of the acid processor and extending into the bottom of the acid processor, and the rotating shaft being provided with a plurality of second stirring rods.

[0018] Preferably, the acid inlet is provided with an acid tube, the lower end of which extends below the liquid surface of the acid processor.

[0019] The advantages of this utility model are:

[0020] 1. This utility model places the outlet of the first pipe below the surface of the alkaline solution, allowing hydrogen sulfide to be directly introduced into the alkaline solution and fully contact it, thus initially improving the absorption rate of hydrogen sulfide. A hydrogen sulfide detector is used to detect whether hydrogen sulfide is present in the air. When hydrogen sulfide is detected, the return pipe draws the hydrogen sulfide into the space above the baffle, while the spray assembly sprays out alkaline solution to absorb the hydrogen sulfide gas again, thereby completely recovering the hydrogen sulfide. The equipment also has a small footprint.

[0021] 2. This utility model features a hollow structure and a vent hole on the first stirring rod, and a hollow section on the rotating shaft. The hollow structure of the first stirring rod is connected to the hollow section and the vent hole, allowing hydrogen sulfide gas to be directly introduced into the hollow section of the rotating shaft. When the first stirring rod rotates, hydrogen sulfide enters the alkaline solution through the vent hole, causing the hydrogen sulfide to diffuse evenly, increasing the contact area between the hydrogen sulfide and the alkaline solution, and improving the initial treatment effect on hydrogen sulfide. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a raw material recovery device for the production of sodium pyrithione.

[0023] In the diagram: 1-Acid processor, 2-Liquid inlet, 3-Acid inlet, 4-Gas outlet, 5-Acid pipe, 6-First pipe, 7-Vacuum pump, 8-Three-way valve, 9-First branch pipe, 10-Second branch pipe, 11-Heating jacket, 12-Alkali tower, 13-Baffle plate, 14-Support rod, 15-Annular pipe, 16-Nozzle, 17-Circulation pipe, 18-Circulation pump, 19-Circulation valve, 20-Hydrogen sulfide detector, 21-Return gas pipe, 22-Fan, 23-Return gas valve, 24-Alkali inlet, 25-Alkali outlet, 26-Rotating shaft, 27-First motor, 28-Rotary joint, 29-Hollow section, 30-First stirring rod, 31-Gas outlet, 32-First liquid outlet, 33-Second liquid outlet, 34-Second motor, 35-Rotating shaft, 36-Second stirring rod. Detailed Implementation

[0024] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0025] like Figure 1 As shown, a raw material recovery device for the production of sodium pyrithione includes an acid processor 1. The acid processor 1 has a liquid inlet 2, an acid inlet 3, and a gas outlet 4 at its top. The gas outlet 4 is connected to an alkali tower 12 via a first pipe 6. A vacuum pump 7 is installed on the first pipe 6. The alkali tower 12 contains a sodium hydroxide solution. The gas outlet of the first pipe 6 is located below the surface of the alkali solution in the alkali tower 12, allowing the sodium hydrosulfide to diffuse upwards and come into full contact with the sodium hydroxide, thus improving the absorption rate of hydrogen sulfide gas. Specifically, the gas outlet of the first pipe 6 is connected to the bottom of the alkali tower 12.

[0026] A baffle 13 is installed above the alkali solution in the alkali tower 12, dividing the tower into upper and lower sections. A first liquid outlet 32 ​​is provided on the baffle 13. A spray assembly is installed above the baffle 13, connected to the lower part of the alkali tower 12 via a circulation pipe 17. The spray assembly includes two vertically oriented support rods 14, the tops of which are connected to the top of the inner wall of the alkali tower 12. An annular pipe 15 is fixed to the bottom of the two support rods 14. Several nozzles 16 are distributed circumferentially on the lower surface of the annular pipe 15, which is connected to the circulation pipe 17. A circulation pump 18 and a circulation valve 19 are installed on the circulation pipe 17. The circulation pump 18 pumps the alkali solution from the lower part of the alkali tower 12 into the area above the baffle 13. A hydrogen sulfide detector 20 is installed below the baffle 13, and a return gas pipe 21 is installed at the top of the alkali tower 12, connecting the area above and below the baffle 13. The return air pipe 21 is equipped with a fan 22 and a return air valve 23. The fan 22 can transport the air below the partition 13 to the top of the partition 13. The side wall of the alkali tower 12 is provided with an alkali inlet 24, and the bottom of the alkali tower 12 is provided with an alkali outlet 25.

[0027] When hydrogen sulfide gas is introduced into a sodium hydroxide solution, some hydrogen sulfide gas may escape from the sodium hydroxide solution. As the hydrogen sulfide gas diffuses upwards, it first passes below the partition 13. Therefore, the hydrogen sulfide detector 20 can promptly detect whether hydrogen sulfide gas is present in the air of the alkali tower 12. The hydrogen sulfide is drawn to the area above the partition 13 using the return gas pipe 21, and then the alkali solution is sprayed out by the spray assembly to absorb the escaped hydrogen sulfide gas, thus fully recovering and utilizing the hydrogen sulfide without occupying a large area. The sodium hydroxide content in the alkali solution is constant. By measuring the sulfide ion content in the alkali solution, it can be determined whether the sodium hydroxide has completely reacted with the hydrogen sulfide to generate sodium hydrosulfide, allowing for timely liquid discharge, recovery and utilization of the raw material sodium hydrosulfide, and replacement with new alkali solution, avoiding interference with the absorption of hydrogen sulfide gas. Since hydrogen sulfide is heavier than air, it tends to accumulate in the lower part of the limited space. Therefore, in a specific embodiment of this invention, the inlet end of the return gas pipe 21 and the hydrogen sulfide detector 20 are located near the surface of the alkali solution.

[0028] Specifically, the alkali tower 12 is equipped with a rotating shaft 26. The top of the rotating shaft 26 passes sequentially upward through the partition 13, the annular pipe 15, and the top of the alkali tower 12, and is connected to a first motor 27. The bottom of the rotating shaft 26 is rotatably connected to the first pipe 6, and the rotating shaft 26 can be rotatably connected to the first pipe 6 through a rotary joint 28. The rotating shaft 26 is rotatably connected to the partition 13 and the alkali tower 12 respectively, and passes through the center of the annular pipe. The lower part of the rotating shaft 26 has a hollow section 29, which is connected to the first pipe 6. The rotating shaft 26 is equipped with several first stirring rods 30. The lowest first stirring rod 30 has a hollow structure and several vent holes 31, and the vent holes 31 are equipped with a waterproof and breathable membrane. The hollow structure of the first stirring rod 30 is connected to the hollow section 29 and the vent holes 31.

[0029] In this invention, hydrogen sulfide gas is directly introduced into the hollow section 29 of the rotating shaft 26. As the first stirring rod 30 rotates, it diffuses into the alkaline solution, increasing the contact area between the hydrogen sulfide and the alkaline solution and preventing the hydrogen sulfide from entering from only one place and diffusing slowly. The first stirring rod 30 stirs the alkaline solution, promoting the absorption of hydrogen sulfide gas.

[0030] Two alkali treatment towers 12 are provided. A first branch pipe 9 and a second branch pipe 10 are connected to the first pipeline 6 via a three-way valve 8. The three-way valve 8 is located near the output end of the vacuum pump 7. The first pipeline 6 is connected to the alkali treatment tower 12 via the first branch pipe 9 and the second branch pipe 10. The connection between the acid processor 1 and the two alkali treatment towers 12 is controlled by the three-way valve 8. When the alkali reaction in one alkali treatment tower 12 is complete, the connection between the acid processor 1 and the completed alkali treatment tower 12 can be closed via the three-way valve 8, and the connection between the acid processor 1 and the other alkali treatment tower 12 can be opened to avoid affecting the recovery of hydrogen sulfide gas.

[0031] The acid processor 1 has a heating jacket 11 on its outer wall and a second liquid outlet 33 at its bottom. A second stirring assembly is located inside the acid processor 1. The second stirring assembly includes a second motor 34, which is located at the top of the acid processor 1. A rotating shaft 35 is connected to the output end of the second motor 34. The rotating shaft 35 is vertically positioned, with its lower end penetrating the top of the acid processor 1 and extending into its bottom. The rotating shaft 35 is rotatably connected to the acid processor 1, and several second stirring rods 36 are mounted on it. The heating jacket 11 heats the acid processor 1, causing hydrogen sulfide to escape from the liquid. The second stirring assembly ensures uniform heating of the liquid and simultaneous uniform mixing of hydrochloric acid and the reaction system, accelerating the escape of hydrogen sulfide. An acid pipe 5 is connected to the acid inlet 3, with its lower end extending below the liquid surface in the acid processor 1. Hydrochloric acid is added directly to the liquid through the acid pipe 5, preventing the hydrochloric acid from evaporating into gas and leaving through the first pipe 6, thus avoiding any impact on the subsequent absorption of hydrogen sulfide gas.

[0032] Detailed operation process

[0033] After the reaction is complete, the reaction system containing sodium pyrithione flows into acid processor 1 through inlet 2. Hydrochloric acid is added to acid processor 1 through acid pipe 5, and simultaneously the second motor 34 is started, driving the rotating shaft 35 to rotate. The rotating shaft 35 drives the second stirring rod 36 to rotate, stirring the liquid. Hydrochloric acid reacts with sodium sulfide in the system to produce hydrogen sulfide, which escapes from the liquid under heating conditions. The vacuum pump 7 is started, and the three-way valve 8 is opened to connect acid processor 1 to the first alkali tower 12. The vacuum pump 7 draws hydrogen sulfide gas into the first alkali tower 12, and the acid-treated liquid in acid processor 1 is discharged from the second liquid outlet 33 to enter the next process.

[0034] Hydrogen sulfide gas enters sequentially from the first pipe 6 into the hollow section 29 of the rotating shaft 26 and the hollow structure of the first stirring rod 30. Simultaneously, the first motor 27 is started, driving the rotating shaft 26 to rotate, which in turn drives the first stirring rod 30 to rotate. As the first stirring rod 30 rotates, the hydrogen sulfide gas diffuses from the outlet 31 into the alkaline solution, where it reacts with the alkaline solution under the stirring action of the first stirring rod 30.

[0035] Hydrogen sulfide detector 20 detects hydrogen sulfide in the air inside the first alkali tower 12. When hydrogen sulfide is detected, blower 22 and return air valve 23 are turned on, and circulation pump 18 and circulation valve 19 are started simultaneously. Blower 22 draws the hydrogen sulfide-containing air below baffle 13 into the space above baffle 13, and circulation pump 18 draws the alkali solution at the bottom of the first alkali tower 12 into circulation pipe 17. The alkali solution flows from circulation pipe 17 into annular pipe 15 and finally sprays out from nozzle 16. The sprayed alkali solution absorbs the hydrogen sulfide gas above baffle 13, and then flows from the first liquid outlet 32 ​​to the bottom of the first alkali tower 12.

[0036] After the sodium hydroxide in the first alkali tower 12 has no absorption capacity, the connection between the acid processor 1 and the first alkali tower 12 is closed via the three-way valve 8, and the connection between the three-way valve 8 and the second alkali tower 12 is opened. The second alkali tower 12 absorbs hydrogen sulfide following the steps of the first alkali tower 12. The alkali solution in the first alkali tower 12 is discharged through its alkali solution outlet 25, and new alkali solution is added through its alkali solution inlet 24.

[0037] It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. Furthermore, it should be understood that after reading the technical description of this utility model, those skilled in the art can make various alterations, modifications, and / or variations to this utility model, and all such equivalent forms also fall within the scope of protection defined by the appended claims.

Claims

1. A raw material recovery device for the production of sodium pyrithione, characterized in that, The system includes an acid processor (1), which has an outlet (4) at the top. The outlet (4) is connected to an alkali tower (12) via a first pipe (6). The outlet of the first pipe (6) is located below the surface of the alkali solution in the alkali tower (12). A partition (13) is provided above the alkali solution, which divides the alkali tower (12) into upper and lower parts. A first liquid outlet (32) is provided on the partition (13). A spray assembly is provided above the partition (13), and the spray assembly is connected to the lower part of the alkali tower (12) through a circulation pipe (17). A hydrogen sulfide detector (20) is provided below the partition (13). A return gas pipe (21) is provided at the upper part of the alkali tower (12), and the return gas pipe (21) connects the upper part of the partition (13) and the lower part of the partition (13). A fan (22) is provided on the return gas pipe (21). An alkali inlet (24) is provided on the side wall of the alkali tower (12), and an alkali outlet (25) is provided at the bottom of the alkali tower (12).

2. The raw material recovery device for the production of sodium pyridinethione according to claim 1, characterized in that, The spray assembly includes two support rods (14), which are vertically arranged. The top ends of the two support rods (14) are connected to the top end of the inner wall of the alkali tower (12). An annular pipe (15) is fixed at the bottom end of the two support rods (14). Several nozzles (16) are distributed circumferentially on the lower surface of the annular pipe (15). The annular pipe (15) is connected to the circulation pipe (17).

3. The raw material recovery device for the production of sodium pyrithione according to claim 2, characterized in that, The outlet end of the first pipe (6) is connected to the bottom of the alkali tower (12); a rotating shaft (26) is vertically installed inside the alkali tower (12), and the top of the rotating shaft (26) passes through the partition (13), the annular pipe (15), and the top of the alkali tower (12) in sequence and is connected to the first motor (27); the bottom end of the rotating shaft (26) is rotatably connected to the first pipe (6), and the lower part of the rotating shaft (26) has a hollow section (29), which is connected to the first pipe (6); The rotating shaft (26) is provided with a plurality of first stirring rods (30), the lowest first stirring rod (30) is a hollow structure and is provided with a plurality of air outlets (31). The hollow structure of the first stirring rod (30) is connected to the hollow section (29) and the air outlets (31), and the air outlets (31) are provided with a waterproof and breathable membrane.

4. The raw material recovery device for the production of sodium pyrithione according to claim 3, characterized in that, The rotating shaft (26) is rotatably connected to the first pipe (6) via a rotary joint (28).

5. The raw material recovery device for the production of sodium pyridinethione according to claim 1, characterized in that, The circulation pipe (17) is equipped with a circulation pump (18) and a circulation valve (19). The return pipe (21) is equipped with a return valve (23).

6. The raw material recovery device for the production of sodium pyridinethione according to claim 3, characterized in that, An air pump (7) is installed on the first pipe (6).

7. A raw material recovery device for the production of sodium pyridinethione according to claim 6, characterized in that, The alkali tower (12) is provided in two; the first pipe (6) is connected to the first branch pipe (9) and the second branch pipe (10) respectively through the three-way valve (8). The three-way valve (8) is close to the output end of the air pump (7). The first pipe (6) is connected to the alkali tower (12) through the first branch pipe (9) and the second branch pipe (10) respectively.

8. The raw material recovery device for the production of sodium pyridinethione according to claim 1, characterized in that, The acid processor (1) has a heating jacket (11) on its outer wall, a liquid inlet (2) and an acid inlet (3) on its top, and a second liquid outlet (33) on its bottom.

9. A raw material recovery device for the production of sodium pyridinethione according to claim 1, characterized in that, The acid processor (1) is provided with a second stirring assembly, which includes a second motor (34). The second motor (34) is located at the top of the acid processor (1). The output end of the second motor (34) is connected to a rotating shaft (35). The rotating shaft (35) is vertically arranged. The lower end of the rotating shaft (35) passes through the top of the acid processor (1) and extends into the bottom of the acid processor (1). Several second stirring rods (36) are provided on the rotating shaft (35).

10. A raw material recovery device for the production of sodium pyridinethione according to claim 8, characterized in that, The acid inlet (3) is provided with an acid tube (5), the lower end of which extends below the liquid surface of the acid processor (1).

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