Reaction device based on phosgenation reaction

Abstract

The invention discloses a reaction device based on phosgenation reaction, and relates to the technical field of phosgenation reaction. The phosgenation reaction device comprises a phosgenation reaction kettle, a mixing pool is fixedly installed in the phosgenation reaction kettle, a phosgenation pipe and a raw material pipe are fixedly installed on the two sides of the phosgenation reaction kettle respectively, one end of the phosgenation pipe and one end of the raw material pipe extend into the mixing pool, an ejector is arranged on the raw material pipe, and the other end of the phosgenation pipe extends into the mixing pool. A micro discharge pump is fixedly mounted at the bottom of the mixing tank, and the water inlet end of the micro discharge pump is communicated with the interior of the mixing tank. According to the phosgene reaction device, by arranging the shunting reaction pipes, a mixed solution is shunted by the shunting reaction pipes, then is input into the phosgene reaction kettle for continuous reaction, and is circularly extracted and discharged by the circulating pump, so that phosgene and raw materials are mixed more uniformly, the reaction progress is accelerated, the putting amount of phosgene is reduced, and the generation rate of reactants and the utilization rate of phosgene are improved; the burden of a tail gas treatment system is relieved.

Description

Technical Field

[0001] The present invention relates to the technical field of phosgenation reaction, and in particular to a reaction device based on phosgenation reaction. Background Art

[0002] Phosgene, also known as carbonyl chloride, is highly toxic, slightly soluble in water, and relatively soluble in benzene, toluene, etc. It is produced by the reaction of carbon monoxide and chlorine under the catalytic action of activated carbon. It is an important organic intermediate used in organic synthesis, the manufacture of dyes, rubber, pesticides and plastics, etc. Phosgene can undergo phosgenation reaction with amides to synthesize key intermediates and release carbon dioxide.

[0003] At present, when phosgene reacts with amide substances, a plurality of reactants are generally mixed and introduced into a reactor separately with phosgene for mixed reaction. Since the utilization rate of phosgene in the phosgenation reaction is low, it is necessary to introduce excess phosgene to improve the synthesis efficiency by increasing the phosgene concentration. However, excess phosgene will not only make it difficult to handle by-products, but also cause a large amount of unused phosgene and by-products to flow into the exhaust gas treatment system, causing the exhaust gas treatment system to be overloaded. Therefore, a reaction device based on phosgenation reaction is proposed. Summary of the invention

[0004] The purpose of the present invention is to solve the problem that excessive phosgene needs to be introduced into the phosgenation reaction process at present, but the excessive phosgene not only makes it difficult to handle the by-products, but also causes a large amount of unused phosgene and by-products to flow into the exhaust gas treatment system, causing the exhaust gas treatment system to be overloaded. The present invention provides a reaction device based on the phosgenation reaction.

[0005] In order to achieve the above-mentioned purpose, the present invention specifically adopts the following technical solutions: A reaction device based on phosgenation reaction comprises a phosgenation reactor, a mixing pool is fixedly installed inside the phosgenation reactor, a phosgene pipe and a raw material pipe are fixedly installed on both sides of the phosgenation reactor, one end of the phosgene pipe and the raw material pipe extend into the interior of the mixing pool, an ejector is arranged on the raw material pipe, a micro discharge pump is fixedly installed at the bottom of the mixing pool, the water inlet end of the micro discharge pump is connected with the interior of the mixing pool, a mixing rotating pipe is rotatably installed at the water outlet end of the micro discharge pump, the bottom end of the mixing rotating pipe is closed, a plurality of evenly distributed shunt reaction tubes are vertically arranged around the mixing rotating pipe, a plurality of reaction tube brackets are fixedly installed around the mixing rotating pipe, the shunt reaction tubes located on the same side are fixedly installed on the plurality of reaction tube brackets, and two shunt reaction tubes are fixedly installed between the shunt reaction tube and the mixing rotating tube. A diversion cross pipe distributed from top to bottom, the diversion cross pipes are all horizontally arranged, a stirring motor is fixedly installed at the bottom of the phosgenation reactor, the output shaft of the stirring motor extends to the interior of the phosgenation reactor and is fixedly installed with a stirring shaft, the top of the stirring shaft is fixedly installed at the bottom end of the mixing rotary tube, a plurality of evenly distributed reinforcing brackets are fixedly installed around the top of the stirring shaft, and a plurality of reaction tube brackets located on the same side are fixedly connected to the reinforcing brackets, a circulation pump is fixedly installed on one side of the phosgenation reactor, a circulation outlet pipe and a circulation return pipe are fixedly installed at the water inlet and outlet ends of the circulation pump, respectively, one end of the circulation outlet pipe is fixedly installed at the bottom of the phosgenation reactor, one end of the circulation return pipe passes through the phosgenation reactor and extends to the interior of the mixing pool, and a tail gas pipe is fixedly installed on one side of the phosgenation reactor.

[0006] Furthermore, a scraper is slidably installed inside the split reaction tube, and a retaining ring is fixedly installed inside the top and bottom ends of the split reaction tube.

[0007] Furthermore, a diversion control valve is provided on each of the diversion transverse pipes, the two diversion transverse pipes located on the same side are located between the two retaining rings, and a grid cylinder is fixedly installed on the bottom of each of the scrapers.

[0008] Furthermore, a spray tower is fixedly installed on the top of the phosgenation reactor, a return air pump is arranged on one side of the spray tower, an exhaust pipe is fixedly installed on the air inlet end of the return air pump, an air inlet pipe is fixedly installed on the air outlet end of the return air pump, one end of the exhaust pipe extends to the interior of the mixing tank, one end of the air inlet pipe extends to the interior of the spray tower, a solvent pipe is fixedly installed on the top of the spray tower, one end of the solvent pipe extends to the interior of the spray tower and a spray plate is fixedly installed, a reflux pipe is fixedly installed on the bottom of the spray tower, and the bottom end of the reflux pipe extends to the interior of the mixing tank.

[0009] Furthermore, a reflux control valve is provided on the reflux pipe.

[0010] Furthermore, a three-way control valve is provided on the circulation outlet pipe, and a flushing pipe is fixedly installed on one end of the three-way control valve.

[0011] Furthermore, one end of the raw material pipe located inside the mixing tank is bent toward one side of the inner wall of the mixing tank.

[0012] Furthermore, scraper plates are fixedly installed on both sides of the stirring shaft, and the scraper plates are in contact with the inner wall of the phosgenation reactor.

[0013] The beneficial effects of the present invention are as follows: 1. The present invention provides a split reaction tube so that the mixed liquid is divided into each split reaction tube after mixing, and then input into the phosgenation reactor to continue the reaction, and then the circulating pump is cyclically extracted and discharged from the phosgenation reactor and the mixing tank, so that the phosgene and the raw material are mixed more evenly, thereby accelerating the progress of the reaction, reducing the amount of phosgene added, improving the generation rate of the reactants and the utilization rate of phosgene, and reducing the burden of the tail gas treatment system; 2. The present invention provides a scraper so that when the mixed liquid in the mixing pool is put into the mixing tank once, the micro-discharge pump stops operating, and the scraper is no longer lifted by the water pressure inside the split transverse pipe. The scraper slides down in the split reaction tube under the action of gravity until it stops sliding after contacting the baffle ring, thereby scraping off the reactants and side reactants remaining on the inner wall of the split reaction tube, thereby reducing the residual products inside the split reaction tube; 3. The present invention sets a shunt control valve so that two shunt control valves cooperate with each other, control the water pressure to lift the scraper from the bottom until the scraper contacts the retaining ring at the top, and then the shunt control valve at the top opens to connect the other shunt transverse pipe, and the two shunt transverse pipes synchronously transport the mixed liquid, so that the scraper is kept at the top of the shunt reaction tube under the action of water pressure, so that it can fall down and scrape the inner wall of the shunt reaction tube later; 4. The present invention sets a spray tower so that the phosgene that is not mixed with the raw material will be extracted and transported to the spray tower by the return air pump. At this time, the solvent pipe will be connected to the solvent source, and the low-temperature solvent will be sprayed into the spray tower through the spray plate to absorb the phosgene inside the spray tower, and then the mixed solvent dissolved with phosgene will be discharged into the mixing pool through the reflux pipe to recover the unused phosgene, thereby improving the recovery rate of phosgene and the mixing degree of phosgene and raw materials; 5. The present invention sets a reflux control valve so that when the spray plate sprays the low-temperature solvent, the reflux control valve remains closed, so that a certain amount of solvent is accumulated inside the spray tower until the solvent covers one end of the air inlet pipe located inside the spray tower, and then phosgene is introduced into the air inlet pipe, so that the phosgene is first washed by the accumulated solvent water and then absorbed by the sprayed solvent, thereby improving the absorption rate of phosgene and accelerating the reflux of phosgene; 6. The present invention provides a three-way control valve and a flushing pipe, so that after a round of reaction, the tail gas and mixed reactants inside the phosgenation reactor are discharged. At this time, the flushing pipe is connected to the cleaning water source, and is sent into the mixing tank by the circulation pump through the circulation return pipe, and the entire circulation pipeline system of the circulation pump, the circulation outlet pipe and the circulation return pipe is flushed, and the internal pipeline system of the mixing tank and the phosgenation reactor is cleaned, so as to further reduce the residual reactants; 7. The present invention provides a scraper plate so that during the mixing reaction of phosgene and raw materials in the phosgenation reactor, the rotating stirring shaft will drive the scrapers on both sides to rotate synchronously, further accelerating the mixing progress of the mixed liquid inside the phosgenation reactor. At the same time, the scraper plate scrapes the inner wall of the phosgenation reactor to scrape off the product attached to the inner wall of the phosgenation reactor, thereby reducing the residue of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 It is a schematic diagram of the internal three-dimensional structure of the phosgenation reactor and the spray tower of the present invention; Figure 3 This is a schematic diagram of the three-dimensional structure of the interior of the phosgenation reactor of the present invention from a first-view perspective; Figure 4 This is a schematic diagram of the second perspective three-dimensional structure of the interior of the phosgenation reactor of the present invention; Figure 5 It is a schematic diagram of the three-dimensional structure of the mixing rotating tube and the split flow reaction tube of the present invention; Figure 6 It is a schematic diagram of the three-dimensional structure of the mixing rotating tube and the stirring shaft of the present invention; Figure 7 It is a schematic diagram of the internal three-dimensional structure of the split flow reaction tube of the present invention; Figure 8 It is a schematic diagram of the internal three-dimensional structure of the spray tower of the present invention; Figure numerals: 1. phosgenation reactor; 2. mixing tank; 3. phosgene pipe; 4. raw material pipe; 5. ejector; 6. micro discharge pump; 7. mixing rotary pipe; 8. reaction tube bracket; 9. diversion reaction tube; 10. diversion cross pipe; 11. diversion control valve; 12. stirring motor; 13. stirring shaft; 14. reinforcement bracket; 15. circulation outlet pipe; 16. circulation pump; 17. circulation return pipe; 18. tail gas pipe; 19. scraper; 20. retaining ring; 21. grid cylinder; 22. spray tower; 23. return air pump; 24. exhaust pipe; 25. air inlet pipe; 26. solvent pipe; 27. spray plate; 28. reflux pipe; 29. ​​reflux control valve; 30. three-way control valve; 31. flushing pipe; 32. scraper plate. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0016] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0018] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0019] like Figures 1 to 8 As shown, a reaction device based on phosgenation reaction includes a phosgenation reactor 1, such as Figure 2 As shown, a mixing tank 2 is fixedly installed inside the phosgenation reactor 1, and a phosgene pipe 3 and a raw material pipe 4 are fixedly installed on both sides of the phosgenation reactor 1. One end of the phosgene pipe 3 and the raw material pipe 4 both extend to the inside of the mixing tank 2. Figure 3 As shown, the raw material pipe 4 is provided with an ejector 5, as shown in FIG. Figure 4 As shown, a micro discharge pump 6 is fixedly installed at the bottom of the mixing tank 2, and the water inlet end of the micro discharge pump 6 is connected to the interior of the mixing tank 2, as shown in FIG. Figure 5 As shown, a mixing rotating tube 7 is rotatably mounted at the outlet end of the micro discharge pump 6, the bottom end of the mixing rotating tube 7 is closed, and a plurality of evenly distributed split flow reaction tubes 9 are vertically arranged around the mixing rotating tube 7, as shown in FIG. Figure 6As shown, a plurality of reaction tube supports 8 are fixedly installed on the peripheral side of the mixing rotating tube 7, and the split reaction tube 9 located on the same side is fixedly installed on the plurality of reaction tube supports 8. Two split cross tubes 10 distributed from top to bottom are fixedly installed between the split reaction tube 9 and the mixing rotating tube 7, and the split cross tubes 10 are all arranged horizontally, as shown in FIG. Figure 4 As shown, a stirring motor 12 is fixedly installed at the bottom of the phosgenation reactor 1, and the output shaft of the stirring motor 12 extends to the interior of the phosgenation reactor 1 and is fixedly installed with a stirring shaft 13. The top of the stirring shaft 13 is fixedly installed at the bottom end of the mixing rotating tube 7, and a plurality of uniformly distributed reinforcing brackets 14 are fixedly installed around the top of the stirring shaft 13. A plurality of reaction tube brackets 8 located on the same side are fixedly connected to the reinforcing bracket 14. A circulation pump 16 is fixedly installed on one side of the phosgenation reactor 1, and a circulation outlet pipe 15 and a circulation return pipe 17 are fixedly installed at the water inlet and outlet ends of the circulation pump 16, respectively. One end of the circulation outlet pipe 15 is fixedly installed at the bottom of the phosgenation reactor 1, and one end of the circulation return pipe 17 passes through the phosgenation reactor 1 and extends to the interior of the mixing tank 2, as shown in FIG. Figure 3 As shown, a tail gas pipe 18 is fixedly installed on one side of the phosgenation reactor 1; specifically, when the reaction device based on the phosgenation reaction is in use, the raw material pipe 4 is connected to the raw material source, the reaction raw material is injected into the mixing tank 2 through the ejector 5, the phosgene pipe 3 is connected to the phosgene source, and phosgene is input into the mixing tank 2, so that the phosgene and the raw material are continuously mixed in the mixing tank 2 for a period of time, and then the micro-discharge pump 6 starts to operate, so that the mixed liquid is pumped into the mixing rotary tube 7, and then input into each branch reaction tube 9 through the branch transverse tube 10 on the side of the mixing rotary tube 7, and then input into the phosgenation reactor 1 through the upper and lower ends of each branch reaction tube 9 for reaction, and at the same time, the stirring motor 12 will drive the stirring shaft 13 to rotate, and then drive each branch reaction tube 9 to rotate synchronously through the mixing rotary tube 7, so as to speed up the mixing progress and improve the phosgenation reaction. The circulation pump 16 on one side of the reactor 1 extracts the mixed liquid in the reaction from the phosgenation reactor 1 through the circulation outlet pipe 15, and then re-inputs it into the mixing tank 2 through the circulation return pipe 17 to carry out a secondary diversion and discharge reaction. By setting the diversion reaction tube 9, the mixed liquid of phosgene and the raw material can be mixed in the mixing tank 2, and then divided into each diversion reaction tube 9 by the mixing transfer tube 7, and then input into the phosgenation reactor 1 to continue the reaction, so that the mixed liquid is diverted by each diversion reaction tube 9. The mixed liquid in the phosgenation reactor 1 will also be cyclically extracted and discharged from the phosgenation reactor 1 and the mixing tank 2 by the circulation pump 16, so that the phosgene and the raw material are mixed more evenly, thereby accelerating the progress of the reaction, reducing the amount of phosgene added, improving the generation rate of the reactants and the utilization rate of phosgene, and reducing the burden on the exhaust gas treatment system.

[0020] like Figure 7As shown, a scraper 19 is slidably installed inside the split reaction tube 9, and a retaining ring 20 is fixedly installed inside the top and bottom ends of the split reaction tube 9; specifically, by arranging the scraper 19, when the mixed liquid in the mixing pool 2 is added once, the micro-discharge pump 6 stops operating, and the scraper 19 is no longer lifted up by the water pressure inside the split cross pipe 10. Then, the scraper 19 will slide down in the split reaction tube 9 under the action of gravity until it contacts the retaining ring 20 and stops sliding, thereby scraping off the reactants and by-reactants remaining on the inner wall of the split reaction tube 9, thereby reducing the residual products inside the split reaction tube 9.

[0021] like Figure 6 As shown, the diversion cross pipe 10 is provided with a diversion control valve 11. Figure 7 As shown, the two diversion transverse pipes 10 located on the same side are located between the two retaining rings 20, and the bottom of the scraper 19 is fixedly installed with a grid tube 21; specifically, by setting the diversion control valve 11, when the micro-discharge pump 6 transports the mixed liquid to the stirring shaft 13 and the diversion transverse pipe 10, the diversion control valve 11 located at the bottom is opened first, and the diversion control valve 11 located at the top remains closed. At this time, the scraper 19 is located at the bottom end of the diversion reaction tube 9, and the grid tube 21 will make the scraper 19 always located At the top of the interface between the diversion cross tube 10 and the diversion reaction tube 9, the mixed liquid is transported to the diversion reaction tube 9 through the diversion cross tube 10 at the bottom, and the water pressure lifts the scraper 19 from the bottom until the scraper 19 contacts the retaining ring 20 at the top, and then the diversion control valve 11 at the top is opened to connect the other diversion cross tube 10. The two diversion cross tubes 10 synchronously transport the mixed liquid, so that the scraper 19 is kept on the top of the diversion reaction tube 9 under the action of water pressure, so that it can fall later to scrape the inner wall of the diversion reaction tube 9.

[0022] like Figure 2 As shown, a spray tower 22 is fixedly installed on the top of the phosgenation reactor 1. Figure 2 As shown, a return air pump 23 is provided on one side of the spray tower 22. Figure 8As shown, an air extraction pipe 24 is fixedly installed at the air inlet end of the return air pump 23, an air inlet pipe 25 is fixedly installed at the air outlet end of the return air pump 23, one end of the air extraction pipe 24 extends to the interior of the mixing tank 2, one end of the air inlet pipe 25 extends to the interior of the spray tower 22, a solvent pipe 26 is fixedly installed on the top of the spray tower 22, one end of the solvent pipe 26 extends to the interior of the spray tower 22 and a spray plate 27 is fixedly installed, a return pipe 28 is fixedly installed at the bottom of the spray tower 22, and the bottom end of the return pipe 28 extends to the interior of the mixing tank 2; specifically By setting up a spray tower 22, the phosgene that is not mixed with the raw materials in the mixing tank 2 will be extracted by the return air pump 23 through the exhaust pipe 24, and then transported to the spray tower 22 through the air inlet pipe 25. At this time, the solvent pipe 26 will be connected to the solvent source, and the low-temperature solvent will be sprayed into the spray tower 22 through the spray plate 27 to absorb the phosgene inside the spray tower 22, and then the mixed solvent dissolved with phosgene will be discharged into the mixing tank 2 through the reflux pipe 28 to recover the unused phosgene, thereby improving the recovery rate of phosgene and the mixing degree of phosgene and raw materials.

[0023] like Figure 8 As shown, a reflux control valve 29 is provided on the reflux pipe 28; specifically, by providing the reflux control valve 29, when the spray disk 27 sprays the low-temperature solvent, the reflux control valve 29 remains in a closed state, so that a certain amount of solvent is accumulated inside the spray tower 22 until the solvent covers one end of the air inlet pipe 25 located inside the spray tower 22, and then phosgene is introduced into the air inlet pipe 25, so that the phosgene is first washed by the accumulated solvent water and then absorbed by the sprayed solvent, thereby increasing the absorption rate of the phosgene and accelerating the reflux of the phosgene.

[0024] like Figure 4 As shown, a three-way control valve 30 is provided on the circulation outlet pipe 15, and a flushing pipe 31 is fixedly installed at one end of the three-way control valve 30; specifically, by providing the three-way control valve 30 and the flushing pipe 31, after a round of phosgenation reaction is completed, the tail gas and mixed reactants inside the phosgenation reactor 1 are discharged, and at this time, the flushing pipe 31 is connected to the cleaning water source and is sent into the mixing tank 2 by the circulation pump 16 through the circulation return pipe 17, so as to flush the entire circulation piping system of the circulation pump 16, the circulation outlet pipe 15 and the circulation return pipe 17, and clean the internal piping system of the mixing tank 2 and the phosgenation reactor 1, so as to further reduce the residual reactants.

[0025] like Figure 3 As shown, one end of the raw material tube 4 located inside the mixing pool 2 is bent toward the inner wall of the mixing pool 2; specifically, by arranging the raw material tube 4 so that the one end of the raw material tube 4 located inside the mixing pool 2 remains in a bent state, the reaction raw materials injected into the mixing pool 2 by the ejector 5 can be injected in an inclined path, thereby allowing the raw materials inside the mixing pool 2 to spirally stir themselves, thereby improving the mixing degree of the raw materials and phosgene.

[0026] like Figure 5 As shown, scraper plates 32 are fixedly installed on both sides of the stirring shaft 13, and the scraper plates 32 are in contact with the inner wall of the phosgenation reactor 1; specifically, by arranging the scraper plates 32, during the mixing reaction of phosgene and raw materials in the phosgenation reactor 1, the rotating stirring shaft 13 will drive the scraper plates 32 on both sides to rotate synchronously, further accelerating the mixing progress of the mixed liquid inside the phosgenation reactor 1, and at the same time, the scraper plates 32 scrape the inner wall of the phosgenation reactor 1, scrape off the product attached to the inner wall of the phosgenation reactor 1, and reduce the residue of the product.

[0027] In summary: when the reaction device based on phosgenation reaction is in use, the raw material pipe 4 is connected to the raw material source, the reaction raw material is injected into the mixing pool 2 through the ejector 5, the phosgene pipe 3 is connected to the phosgene source, and phosgene is input into the mixing pool 2, so that the phosgene and the raw material are continuously mixed in the mixing pool 2 for a period of time, and then the micro-discharge pump 6 starts to operate, so that the mixed liquid is pumped into the mixing rotary tube 7, and then input into each branch reaction tube 9 through the branch transverse pipe 10 on the side of the mixing rotary tube 7, and then input into the phosgenation reactor 1 through the upper and lower ends of each branch reaction tube 9 for reaction, and at the same time, the stirring motor 12 will drive the stirring shaft 13 to rotate, and then drive each branch reaction tube 9 to rotate synchronously through the mixing rotary tube 7 to speed up the mixing progress, and the circulation pump 16 on one side of the phosgenation reactor 1 is discharged from the circulating outlet pipe 15. The mixed liquid in the reaction is extracted from the phosgenation reactor 1 and then re-input into the mixing tank 2 through the circulation return pipe 17 for secondary diversion and discharge reaction. By setting the diversion reaction tube 9, the mixed liquid of phosgene and raw materials can be mixed in the mixing tank 2, and then divided into each diversion reaction tube 9 by the mixing transfer tube 7, and then input into the phosgenation reactor 1 to continue the reaction, so that the mixed liquid is diverted by each diversion reaction tube 9. The mixed liquid in the phosgenation reactor 1 will also be circulated and extracted and discharged between the phosgenation reactor 1 and the mixing tank 2 by the circulation pump 16, so that the phosgene and raw materials are mixed more evenly, thereby accelerating the progress of the reaction, reducing the amount of phosgene added, improving the generation rate of the reactants and the utilization rate of phosgene, and reducing the burden on the tail gas treatment system. By setting the scraper 19, when the mixed liquid When the mixed liquid in the combined pool 2 is put into the tank 2 once, the micro-discharge pump 6 stops operating. After the scraper 19 is no longer lifted by the water pressure inside the shunt transverse pipe 10, the scraper 19 will slide down in the shunt reaction tube 9 under the action of gravity until it stops sliding after contacting the retaining ring 20, and then the reactants and side reactants remaining on the inner wall of the shunt reaction tube 9 are scraped off together, thereby reducing the residual products inside the shunt reaction tube 9. By setting the shunt control valve 11, when the micro-discharge pump 6 transports the mixed liquid to the stirring shaft 13 and the shunt transverse pipe 10, the shunt control valve 11 at the bottom is opened first, and the shunt control valve 11 at the top remains closed. At this time, the scraper 19 is located at the bottom end of the shunt reaction tube 9, and the grid tube 21 ensures that the scraper 19 is always located between the shunt transverse pipe 10 and the shunt At the top of the reaction tube 9 interface, the mixed liquid is transported to the diversion reaction tube 9 through the diversion cross pipe 10 at the bottom, and the water pressure lifts the scraper 19 from the bottom until the scraper 19 contacts the baffle ring 20 at the top, and then the diversion control valve 11 at the top is opened to connect the other diversion cross pipe 10. The two diversion cross pipes 10 synchronously transport the mixed liquid, so that the scraper 19 is kept at the top of the diversion reaction tube 9 under the action of water pressure, so that it can fall and scrape the inner wall of the diversion reaction tube 9 later. By setting up a spray tower 22, the phosgene that is not mixed with the raw material in the mixing pool 2 will be extracted by the return air pump 23 through the exhaust pipe 24, and then transported to the spray tower 22 through the air inlet pipe 25. At this time, the solvent pipe 26 will be connected to the solvent source, and the low-temperature solvent will be sprayed into the spray tower 22 through the spray plate 27.The phosgene inside the spray tower 22 is absorbed, and then the mixed solvent containing phosgene is discharged into the mixing pool 2 through the reflux pipe 28, and the unused phosgene is recovered, thereby improving the recovery rate of phosgene and the mixing degree of phosgene and raw materials. By setting the reflux control valve 29, when the spray plate 27 sprays the low-temperature solvent, the reflux control valve 29 remains closed, so that a certain amount of solvent is accumulated inside the spray tower 22 until the solvent covers one end of the air inlet pipe 25 located inside the spray tower 22, and then the air inlet pipe 25 is passed into the phosgene, so that the phosgene is first washed by the accumulated solvent water and then absorbed by the sprayed solvent, thereby improving the absorption rate of phosgene and accelerating the reflux of phosgene. By setting the three-way control valve 30 and the flushing pipe 31, after a round of phosgenation reaction is completed, the tail gas and mixed reactants inside the phosgenation reactor 1 are discharged. At this time, the flushing pipe 31 is connected to the cleaning water source and is sent into the mixing pool 2 by the circulating pump 16 through the circulating return pipe 17. In the process, the entire circulation pipeline system of the circulation pump 16, the circulation outlet pipe 15 and the circulation return pipe 17 is flushed, and the internal pipeline system of the mixing tank 2 and the phosgenation reactor 1 is cleaned to further reduce the residual reactants. By setting the raw material pipe 4, the end of the raw material pipe 4 located inside the mixing tank 2 is kept in a bent state, so that the reaction raw materials injected into the mixing tank 2 by the ejector 5 can be injected in an inclined path, thereby causing the raw materials inside the mixing tank 2 to spirally stir by themselves, thereby improving the mixing degree of the raw materials and phosgene. By setting the scraper plate 32, during the mixing reaction of phosgene and raw materials in the phosgenation reactor 1, the rotating stirring shaft 13 will drive the scraper plates 32 on both sides to rotate synchronously, further accelerating the mixing progress of the mixed liquid inside the phosgenation reactor 1. At the same time, the scraper plate 32 scrapes the inner wall of the phosgenation reactor 1 to scrape off the product attached to the inner wall of the phosgenation reactor 1, thereby reducing the residual product.

[0028] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A reaction device based on phosgenation reaction, characterized in that: The invention comprises a phosgenation reactor (1), wherein a mixing tank (2) is fixedly installed inside the phosgenation reactor (1), a phosgene pipe (3) and a raw material pipe (4) are fixedly installed on both sides of the phosgenation reactor (1), one end of the phosgene pipe (3) and the raw material pipe (4) both extend into the interior of the mixing tank (2), an ejector (5) is arranged on the raw material pipe (4), a micro discharge pump (6) is fixedly installed at the bottom of the mixing tank (2), and a water inlet end of the micro discharge pump (6) is connected to the interior of the mixing tank (2). A mixing rotating tube (7) is rotatably mounted on the water outlet end of the micro discharge pump (6), the bottom end of the mixing rotating tube (7) is closed, a plurality of evenly distributed shunt reaction tubes (9) are vertically arranged around the circumference of the mixing rotating tube (7), a plurality of reaction tube brackets (8) are fixedly mounted around the circumference of the mixing rotating tube (7), the shunt reaction tubes (9) located on the same side are fixedly mounted on the plurality of reaction tube brackets (8), and two shunt cross tubes (1) distributed from top to bottom are fixedly mounted between the shunt reaction tubes (9) and the mixing rotating tube (7). 0), the flow dividing transverse pipes (10) are all arranged horizontally, a stirring motor (12) is fixedly installed at the bottom of the phosgenation reactor (1), the output shaft of the stirring motor (12) extends into the interior of the phosgenation reactor (1) and is fixedly installed with a stirring shaft (13), the top end of the stirring shaft (13) is fixedly installed at the bottom end of the mixing rotating tube (7), a plurality of uniformly distributed reinforcing brackets (14) are fixedly installed around the top end of the stirring shaft (13), and a plurality of reaction tube brackets (8) located on the same side are all connected to the reinforcing brackets (14). The bracket (14) is fixedly connected, a circulation pump (16) is fixedly installed on one side of the phosgenation reactor (1), and a circulation outlet pipe (15) and a circulation return pipe (17) are respectively fixedly installed on the water inlet and water outlet ends of the circulation pump (16), one end of the circulation outlet pipe (15) is fixedly installed on the bottom of the phosgenation reactor (1), one end of the circulation return pipe (17) passes through the phosgenation reactor (1) and extends to the interior of the mixing tank (2), and a tail gas pipe (18) is fixedly installed on one side of the phosgenation reactor (1).

2. A reaction device based on phosgenation reaction according to claim 1, characterized in that: A scraper (19) is slidably mounted inside the split reaction tube (9), and a retaining ring (20) is fixedly mounted inside the top end and the bottom end of the split reaction tube (9).

3. A reaction device based on phosgenation reaction according to claim 2, characterized in that: The diversion cross pipe (10) is provided with a diversion control valve (11), the two diversion cross pipes (10) located on the same side are located between the two retaining rings (20), and the bottom of the scraper (19) is fixedly mounted with a grid cylinder (21).

4. A reaction device based on phosgenation reaction according to claim 1, characterized in that: A spray tower (22) is fixedly installed on the top of the phosgenation reactor (1), a return air pump (23) is arranged on one side of the spray tower (22), an exhaust pipe (24) is fixedly installed on the air inlet end of the return air pump (23), an intake pipe (25) is fixedly installed on the air outlet end of the return air pump (23), one end of the exhaust pipe (24) extends to the interior of the mixing tank (2), one end of the intake pipe (25) extends to the interior of the spray tower (22), a solvent pipe (26) is fixedly installed on the top of the spray tower (22), one end of the solvent pipe (26) extends to the interior of the spray tower (22) and a spray plate (27) is fixedly installed, and a reflux pipe (28) is fixedly installed on the bottom of the spray tower (22), and the bottom end of the reflux pipe (28) extends to the interior of the mixing tank (2).

5. A reaction device based on phosgenation reaction according to claim 4, characterized in that: The reflux pipe (28) is provided with a reflux control valve (29).

6. The reaction device based on phosgenation reaction according to claim 1, characterized in that: A three-way control valve (30) is provided on the circulation outlet pipe (15), and a flushing pipe (31) is fixedly mounted on one end of the three-way control valve (30).

7. The reaction device based on phosgenation reaction according to claim 1, characterized in that: One end of the raw material pipe (4) located inside the mixing tank (2) is bent toward one side of the inner wall of the mixing tank (2).

8. The reaction device based on phosgenation reaction according to claim 1, characterized in that: Scraping plates (32) are fixedly mounted on both sides of the stirring shaft (13), and the scraping plates (32) are in contact with the inner wall of the phosgenation reactor (1).

Images