Triphosgene dissolving tank device for tetrabutyl urea

Abstract

The triphosgene dissolving tank device comprises a heat exchanger and a dissolving kettle, the heat exchanger is communicated into the dissolving kettle through a material conveying pipe, a dissolving kettle jacket is arranged outside the dissolving kettle, and a second circulating water inlet and a second circulating water outlet are formed in the bottom and the upper portion of the dissolving kettle jacket respectively. The top of the dissolving kettle is fixedly connected with a stirring motor, the output end of the stirring motor is fixedly connected with a stirring shaft, the stirring shaft is arranged in the dissolving kettle and rotatably connected with the dissolving kettle, the middle and the bottom of the stirring shaft are fixedly connected with stirring impellers respectively, and a discharging port is formed in the bottom of the dissolving kettle. An inclined third feeding pipe is arranged on the side, away from the stirring motor, of the top of the dissolving kettle, a butterfly valve is arranged in the middle of the third feeding pipe, the upper portion of the third feeding pipe is communicated to an exhaust pipe of the dissolving kettle through a pipeline branch, a quick-release cover plate is arranged at the end of the third feeding pipe, and a nitrogen inlet is formed between the butterfly valve on the third feeding pipe and the quick-release cover plate. Therefore, the replacement and emission of harmful gas can be realized.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical engineering, in particular to a solid phosgene dissolving tank device for tetrabutylurea. Background Art

[0002] Tetrabutylurea is an important organic chemical and has important application value in the chemical industry. It is mainly used in the new process of producing hydrogen peroxide by the anthraquinone method as a solvent for hydroanthraquinone. This application is based on the advantages of tetrabutylurea compared with trioctyl phosphate in terms of the solubility of hydroanthraquinone, the distribution coefficient of H 2 O 2 in two phases, the density difference from water, and the surface tension.

[0003] In the production process of tetrabutylurea, toluene needs to be first pumped into the dissolving kettle, heated to 50 - 60 °C, then the manhole cover is opened, and solid phosgene is slowly added until the addition of solid phosgene is completed. The manhole cover is closed, and after stirring for a period of time, triphosgene is dissolved in toluene for later synthesis use. However, in the prior art, it is difficult to fully dissolve solid phosgene, resulting in large environmental pollution, strong toxicity, dangerous processes, and low efficiency. Summary of the Utility Model

[0004] Aiming at the above defects, the utility model provides a solid phosgene dissolving tank device for tetrabutylurea, which can accelerate the dissolution of solid phosgene and effectively avoid the leakage of poisonous gas.

[0005] To achieve the above purpose, the utility model provides the following technical solution: A solid phosgene dissolving tank device for tetrabutylurea, including a heat exchanger and a dissolving kettle. The heat exchanger is connected to the inside of the dissolving kettle through a feeding pipe. A dissolving kettle jacket is arranged outside the dissolving kettle. A second circulating water inlet and a second circulating water outlet are respectively opened at the bottom and the upper part of the dissolving kettle jacket. A stirring motor is fixedly connected to one side of the top of the dissolving kettle. The output end of the stirring motor is fixedly connected to a stirring shaft. The stirring shaft is arranged inside one side of the dissolving kettle and is rotatably connected to the dissolving kettle. A first stirring impeller and a second stirring impeller are respectively fixedly connected to the middle and the bottom of the stirring shaft. A discharging port is opened at the bottom of the dissolving kettle. An inclined third feeding pipe is arranged on the side of the top of the dissolving kettle away from the stirring motor. A butterfly valve is arranged in the middle of the third feeding pipe. The upper part of the third feeding pipe is connected to the exhaust pipe of the dissolving kettle through a pipeline branch. A quick-release cover plate is arranged at the end of the third feeding pipe. A nitrogen inlet is arranged between the butterfly valve and the quick-release cover plate on the third feeding pipe.

[0006] As a further improvement of the utility model, a check valve is arranged on the pipeline branch.

[0007] As a further improvement of the utility model, a plurality of legs are fixedly connected to the outside of the dissolving kettle jacket.

[0008] As a further improvement of the present utility model, a plurality of baffle plates are arranged in a circumferential array inside the dissolution kettle, and the baffle plates are detachably connected inside the dissolution kettle.

[0009] As a further improvement of the present utility model, a thermometer sleeve is provided on one side of the lower part of the dissolution kettle, and the end of the thermometer sleeve is located inside the dissolution kettle.

[0010] As a further improvement of the present utility model, the first stirring blades on the first stirring impeller are all straight blades.

[0011] As a further improvement of the present utility model, the second stirring blades on the second stirring impeller are all inclined blades.

[0012] As a further improvement of the present utility model, a temperature sensor is provided on the feed pipe.

[0013] As a further improvement of the present utility model, the lower part of the dissolution kettle is conical.

[0014] The beneficial effects of the present utility model:

[0015] 1. Harmful gases may be generated during the production of tetrabutylurea. By setting a quick-release cover plate and a butterfly valve at the third feed pipe, it is possible to prevent harmful gases from leaking from the feed port during the feeding process, and by setting a nitrogen inlet at the third feed pipe and injecting nitrogen into the third feed pipe through the nitrogen inlet, the harmful gases in the third feed pipe can be effectively replaced and diluted by nitrogen, preventing leakage from the feed point, reducing environmental pollution and harm to people.

[0016] 2. The stirring shaft inside the dissolution kettle is eccentrically arranged, so that the stirring shaft is away from the side where the solid phosgene is put in, avoiding direct contact between the stirring shaft and the solid phosgene, enabling the solid phosgene to dissolve better, preventing the stirring motor from being overloaded, and internally provided with baffle plates to improve the dissolution efficiency and heat exchange rate.

[0017] 3. By setting a heat exchanger to preheat toluene, the toluene entering the dissolution kettle can be initially heated to 50 - 60 °C, which can improve the dissolution efficiency of toluene and solid phosgene.

[0018] 4. The lower part of the dissolution kettle is arranged in a conical contraction, which can ensure that the product and the undissolved solid phosgene can be fully discharged from the dissolution kettle. Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the device for dissolving solid phosgene in tetrabutylurea of the present utility model.

[0020] In the figure: 1 - heat exchanger, 100 - first circulating water inlet, 101 - first circulating water outlet, 102 - first toluene inlet, 103 - first toluene outlet; 2 - feeding pipe, 200 - temperature sensor;

[0021] 3 - dissolving kettle, 300 - second toluene inlet, 301 - dissolving kettle jacket, 302 - second circulating water inlet, 303 - second circulating water outlet, 304 - thermometer sleeve, 305 - leg, 306 - discharging port;

[0022] 4 - stirring motor, 5 - coupling, 6 - stirring shaft, 7 - first stirring impeller, 8 - second stirring impeller, 9 - mounting plate, 10 - baffle plate, 11 - exhaust pipe, 12 - pipeline branch, 13 - third feed pipe, 14 - quick - release cover plate, 15 - butterfly valve, 16 - nitrogen inlet, 17 - check valve. Specific embodiments

[0023] In order to make the purpose, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific examples described herein are only used to explain the present utility model and are not used to limit the present utility model. The directional terms mentioned in the following embodiments, such as: up, down, left, right, front or back, etc., are only references to the directions in the accompanying drawings. Therefore, the directional terms used are for illustration and not for limiting the present utility model. In addition, in all embodiments, the same reference numerals represent the same elements.

[0024] As Figure 1 shown, a solid phosgene dissolving tank device for tetrabutylurea includes a heat exchanger 1 and a dissolving kettle 3. The heat exchanger 1 includes a heating chamber, and a heat exchange chamber is circumferentially arranged outside the heating chamber. The heating chamber and the heat exchange chamber are not communicated. A first circulating water inlet 100 is provided at the lower part on one side of the heat exchange chamber, and a first circulating water outlet 101 is provided at the upper part on the other side of the heat exchange chamber. A first toluene inlet 102 is provided at the bottom of the heating chamber, and a first toluene outlet 103 is provided at the top of the heating chamber.

[0025] As a further illustration of this example, when starting to work, first, heating water at a temperature of 60 °C is continuously introduced into the first circulating water inlet 100. The heating water continuously flows in the heat exchange chamber and flows out from the upper first circulating water outlet 101 for reciprocating circulation, so that the toluene entering the heating chamber from the first toluene inlet 102 is heated. When the toluene is discharged from the upper first toluene outlet 103, the temperature of the toluene reaches 50 - 60 °C.

[0026] A pipeline connection flange is provided at the first toluene outlet 103 of the heat exchanger 1. A feed pipe 2 is fixedly connected to the first toluene outlet 103 through the connection flange. The feed pipe 2 is a rigid pipeline, and a temperature sensor 200 for detecting the temperature of the toluene conveyed in the feed pipe 2 is installed on the feed pipe 2. One end of the feed pipe 2 communicates with the heating chamber of the heat exchanger 1, and the other end of the feed pipe 2 communicates with the inside of the dissolution kettle 3. The feed pipe 2 and the second toluene inlet 300 provided on one side of the top of the dissolution kettle 3 are fixed through a connection flange.

[0027] A stirring motor 4 is fixedly connected to one side of the outer top of the dissolution kettle 3 near the second toluene inlet 300. The output end of the stirring motor 4 is fixedly connected to a stirring shaft 6 through a coupling 5. The stirring shaft 6 extends into the inside of the dissolution kettle 3 and is rotatably connected thereto. The stirring shaft 6 is located at an eccentric position on one side inside the dissolution kettle 3. A first stirring impeller 7 is fixedly connected to the middle of the stirring shaft 6. The six first stirring blades on the first stirring impeller 7 are all straight blades, and the six first stirring blades are arranged in a circular array. A second stirring impeller 8 is fixedly connected to the bottom of the stirring shaft 6. The six second stirring blades on the second stirring impeller 8 are all inclined blades, and the six second stirring blades are arranged in a circular array.

[0028] As a further illustration of this example, the stirring shaft 6 inside the dissolution kettle 3 is eccentrically arranged, so that the stirring shaft 6 is away from the side where the solid phosgene is put in, avoiding direct collision and contact between the stirring shaft 6 and the solid phosgene, enabling the solid phosgene to dissolve better, and preventing the stirring motor 4 from being overloaded.

[0029] Four baffle plates 10 are provided inside the dissolution kettle 3. The four baffle plates 10 are arranged in a circular array along the inside of the dissolution kettle 3. The upper and lower parts of the baffle plates 10 are detachably connected to the mounting plates 9 through bolts, and the mounting plates 9 are fixedly connected to the inner wall of the dissolution kettle 3. The lower part of the dissolution kettle 3 is conical, and a discharge port 306 is opened at the bottom end of the lower part of the dissolution kettle 3. The discharge port 306 is arranged vertically downward.

[0030] A dissolution kettle jacket 301 is provided outside the dissolution kettle 3. A second circulating water inlet 302 is provided at the bottom of the dissolution kettle jacket 301. The second circulating water inlet 302 is arranged vertically downward. A second circulating water outlet 303 is provided on one side of the upper part of the dissolution kettle jacket 301. The second circulating water outlet 303 is arranged horizontally. Legs 305 are fixedly connected to the outside of the dissolution kettle jacket 301. A thermometer sleeve 304 is provided on one side of the lower part of the dissolution kettle 3. The thermometer sleeve 304 obliquely penetrates the dissolution kettle jacket 301 and acts on the inside of the dissolution kettle 3. A thermometer can be installed inside it through the thermometer sleeve 304 for monitoring the working temperature inside the reaction kettle.

[0031] On one side of the top of the dissolving kettle 3 away from the second toluene inlet 300, there is a third feed pipe 13 connected to the inside. The third feed pipe 13 has a relatively large diameter and is inclined. A butterfly valve 15 is provided in the middle of the third feed pipe 13. The butterfly valve 15 used is a double-layer butterfly valve with better sealing performance. A nitrogen inlet 16 is opened on the third feed pipe 13. Nitrogen can be injected into the inside of the dissolving kettle 3 through the third feed pipe 13 to displace the toxic gas in the third feed pipe 13, reducing environmental pollution and harm to people. The end of the third feed pipe 13 is provided with a quick-release cover plate 14 that is convenient to open and close. The nitrogen inlet 16 is located between the butterfly valve 15 and the quick-release cover plate 14. An upper part of the third feed pipe 13 is provided with a pipeline branch 12. The pipeline branch 12 is connected to the upper part of the exhaust pipe 11. A check valve 17 is provided on the pipeline branch 12. Through the check valve 17, it can be ensured that the gas can only enter the exhaust pipe 11 from the third feed pipe 13. The bottom of the exhaust pipe 11 is fixed on the top of the dissolving kettle 3 and is connected to the inside of the dissolving kettle 3.

[0032] The working principle and usage process of the present utility model: Use a hydraulic pump to press toluene into the heat exchanger 1. The toluene is transported upward in the heat exchanger 1 and is heated to 50 - 60 °C during the transportation process. Then it enters the dissolving kettle 3 through the feed pipe 2. Start the stirring motor 4 to drive the stirring shaft 6 to rotate. Hot water with a temperature of 60 °C continuously circulates in the dissolving kettle jacket 301 outside the dissolving kettle 3. It can be detected through the thermometer in the thermometer sleeve 304 to ensure that the reaction temperature in the dissolving kettle 3 is maintained at 60 °C.

[0033] Open the quick-release cover plate 14 and put solid phosgene into the third feed pipe 13. Then close the quick-release cover plate 14 and slowly open the butterfly valve 15 to make the solid phosgene flow into the dissolving kettle 3 for dissolution. The reaction between solid phosgene and toluene will produce harmful gases. After all the solid phosgene has flowed into the dissolving kettle 3, close the butterfly valve 15. During the feeding process, some harmful gases will enter the third feed pipe 13.

[0034] At this time, the quick-release cover plate 14 and the butterfly valve 15 at the third feed pipe 13 are in a closed state. Inject nitrogen into the third feed pipe 13 through the nitrogen inlet 16. The nitrogen displaces the waste gas in the third feed pipe 13, enters the exhaust pipe 11 from the pipeline branch 12, and then dilutes the harmful gas entering the exhaust pipe 11 from the dissolving kettle 3 to reduce the concentration of harmful substances in the waste gas. After the replacement is completed, open the quick-release cover plate 14 again to put solid phosgene and continuously repeat the above steps. When the toluene injected into the dissolving kettle 3 has completely reacted, open the discharge port 306 at the bottom to completely empty the dissolving kettle 3. At this time, tetrabutylurea liquid is obtained, which may contain some undissolved solid phosgene inside.

[0035] The above are only the preferred embodiments of the present utility model. The protection scope of the present utility model is not limited to the above-mentioned implementation measures. All technical solutions falling within the concept of the present utility model belong to the protection scope of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present utility model, several improvements and refinements should also be regarded as the protection scope of the present utility model.

Claims

1. A solid phosgene dissolving tank device for tetrabutyl urea, comprising a heat exchanger (1) and a dissolving kettle (3), characterized in that: The heat exchanger (1) is connected to the inside of the dissolving kettle (3) through a feed pipe (2); a dissolving kettle jacket (301) is provided outside the dissolving kettle (3); a second circulating water inlet (302) and a second circulating water outlet (303) are respectively provided at the bottom and the top of the dissolving kettle jacket (301); a stirring motor (4) is fixedly connected to one side of the top of the dissolving kettle (3); an output end of the stirring motor (4) is fixedly connected to a stirring shaft (6); the stirring shaft (6) is arranged at one side of the inside of the dissolving kettle (3) and is rotatably connected to the dissolving kettle (3); a first stirring shaft (6) is fixedly connected to the middle and the bottom of the stirring shaft (6); A stirring impeller (7) and a second stirring impeller (8); a discharge port (306) is provided at the bottom of the dissolving kettle (3); a third inclined feed pipe (13) is provided at the top of the dissolving kettle (3) on a side away from the stirring motor (4); a butterfly valve (15) is provided at the middle of the third feed pipe (13); an upper portion of the third feed pipe (13) is connected to an exhaust pipe (11) of the dissolving kettle (3) through a pipeline branch (12); a quick-release cover plate (14) is provided at the end of the third feed pipe (13); and a nitrogen inlet (16) is provided between the butterfly valve (15) and the quick-release cover plate (14) on the third feed pipe (13).

2. The solid phosgene dissolving tank device for tetrabutyl urea according to claim 1, characterized in that: A one-way valve (17) is provided on the pipeline branch (12).

3. The solid phosgene dissolving tank device for tetrabutyl urea according to claim 2, characterized in that: A plurality of legs (305) are fixedly connected to the outer side of the dissolving kettle jacket (301).

4. The solid phosgene dissolving tank device for tetrabutyl urea according to claim 1, characterized in that: The dissolving kettle (3) has a plurality of baffle plates (10) in an internal circumferential array, and the baffle plates (10) are detachably connected to the inside of the dissolving kettle (3).

5. The solid phosgene dissolving tank device for tetrabutyl urea according to claim 1, characterized in that: A thermometer sleeve (304) is provided on one side of the lower portion of the dissolving kettle (3), and an end portion of the thermometer sleeve (304) is located inside the dissolving kettle (3).

6. The solid phosgene dissolving tank device for tetrabutyl urea according to claim 1, characterized in that: The first stirring blades on the first stirring impeller (7) are all straight blades.

7. The solid phosgene dissolving tank device for tetrabutyl urea according to claim 1, characterized in that: The second stirring blades on the second stirring impeller (8) are all inclined blades.

8. The solid phosgene dissolving tank device for tetrabutyl urea according to claim 1, characterized in that: The material conveying pipe (2) is provided with a temperature sensor (200).

9. The solid phosgene dissolving tank device for tetrabutyl urea according to claim 1, characterized in that: The lower part of the dissolving kettle (3) is conical.

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