Reaction device based on dichlorobenzonitrile synthesis and use method thereof

Abstract

The invention discloses a reaction device based on dichlorobenzonitrile synthesis and a use method thereof, and relates to the field of reaction devices.According to the technical scheme, the reaction device comprises a reaction tank and a cover located at the top end of the reaction tank, a heating interlayer is arranged on the reaction tank, and a spiral conveying pipe surrounding a reaction cavity in the middle of the reaction tank is arranged in the heating interlayer; the heating medium is conveyed through the spiral conveying pipe, and the gap between the heating interlayer and the spiral conveying pipe is filled with the heat preservation material, so that the heating medium is conveyed around the reaction cavity in the heating interlayer through the spiral conveying pipe, and the spirally distributed conveying pipe can enable the heating medium to uniformly act on the outer wall of the reaction cavity; heat loss is reduced through the heat preservation material between the heating interlayer and the spiral conveying pipe, accurate control and uniform distribution of the reaction temperature are achieved, side reactions caused by local overheating are avoided, and therefore generation of polychlorinated impurities is reduced, and the purity of the dichlorobenzonitrile product is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of reaction devices, more particularly, it relates to a reaction device based on dichlorobenzene synthesis and a method of using the same. BACKGROUND

[0002] Dichlorobenzene is an important organic synthesis intermediate, which has a wide application in the fields of pesticides, medicines, dyes, etc. For example, in the field of pesticides, it can be used to synthesize various high-efficiency and low-toxicity insecticides and herbicides; in the field of medicine, it plays a key role in the synthesis of some drugs, which makes the frequency of dichlorobenzene synthesis by reaction device higher and higher.

[0003] However, the traditional reaction device usually adopts a simple jacket heating structure, which is difficult to realize precise control and uniform distribution of the reaction temperature, resulting in local overheating, causing side reactions, generating polychlorinated impurities, and reducing the purity of dichlorobenzene product; at the same time, the single stirring paddle design (i.e. a stirring paddle is arranged in the center area of the reaction tank) of the traditional reaction device cannot effectively solve the mass transfer resistance problem between dichlorobenzene, aqueous catalyst and organic phase materials, and is easy to form liquid-liquid and solid-liquid stratification, resulting in slow and incomplete reaction rate.

[0004] Therefore, in order to solve the above technical problems, the present application provides a reaction device based on dichlorobenzene synthesis and a method of using the same. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present application is to provide a reaction device based on dichlorobenzene synthesis and a method of using the same.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a reaction device based on dichlorobenzene synthesis, comprising a reaction tank and a cover body located at the top end of the reaction tank, a heating sandwich is arranged on the reaction tank, and a spiral conveying pipe is arranged around the middle reaction cavity of the reaction tank in the heating sandwich, the heating medium is conveyed through the spiral conveying pipe, and the gap between the heating sandwich and the spiral conveying pipe is filled with heat preservation material, the reaction device based on dichlorobenzene synthesis further comprises: A stirring device is arranged on the cover body, comprising a main stirring paddle and a plurality of auxiliary stirring paddles surrounding the main stirring paddle, a motor is installed at the top end of the cover body, and the motor drives the main stirring paddle and the auxiliary stirring paddles to rotate together through a linkage assembly.

[0007] Preferably, the linkage assembly comprises a bearing A embedded and fixed at the top end of the cover, and a rotating rod A is fixedly connected in the inner ring part of the bearing A, the transmission shaft of the motor is connected with the head of the rotating rod A, the bottom of the rotating rod A is fixedly connected with a large gear, a plurality of small gears are meshingly connected on the outer side wall of the large gear, the main stirring paddle is fixed at the bottom center part of the large gear, and a plurality of auxiliary stirring paddles are respectively fixed at the bottom center part of the small gears.

[0008] Preferably, a plurality of bearing seats are arranged in a circumferential array on the inner side wall of the cover, a bearing B is installed in each of the bearing seats, and a rotating rod B is fixedly connected in the inner ring part of the bearing B, and the bottom end of the rotating rod B is connected with the small gear.

[0009] Preferably, the main stirring paddle is an axial flow type propelling type stirring paddle, and the auxiliary stirring paddle is a radial type turbine type stirring paddle.

[0010] Preferably, the bottom end of the reaction tank is connected with an iron counterweight base through a support rod, and a discharge pipe with a valve is arranged at the bottom center part of the reaction tank.

[0011] Preferably, the two ends of the spiral conveying pipe are respectively provided with a medium inlet pipe and a medium outlet pipe, the medium inlet pipe extends out from the top of the reaction tank, and the medium outlet pipe extends out from the bottom of the reaction tank.

[0012] Preferably, a plurality of pipeline connection pipes are embeddedly fixed on the cover in a circumferential array and are arranged staggered with the bearing seats, automatic control valves are installed on the pipeline connection pipes, and the pipeline connection pipes are respectively connected with a dichlorobenzene feeding pipeline, a water dropping pipeline, an acetic acid feeding pipeline, a recovered concentrated acetic acid feeding pipeline, and a solid material conveying pipeline.

[0013] Preferably, an annular groove is formed at the top end of the reaction tank for inserting the cover, and a rubber coating layer is arranged at the insertion part of the cover.

[0014] Preferably, groove seats are fixedly connected on both sides of the outer side wall of the reaction tank, the top end of the cover is connected with protrusions through connecting plates, protrusion bottoms are fixedly connected with screw rods on both sides, through holes are formed in the inner bottom wall of the groove seats for the screw rods to pass through, nuts are threadedly connected on the outer side wall of the screw rods, a magnet is installed at the middle part of the bottom end of the protrusion, and an iron plate is fixedly connected with the magnet at the middle part of the inner bottom wall of the groove seat.

[0015] The method for using the reaction device for synthesizing dichlorobenzene comprises the following steps: Step one: insert the cover into the annular groove at the top end of the reaction tank, ensure that the rubber coating layer fills the gap, fix the cover through the screw-nut structure of the groove seat and the protrusion and the magnet-iron plate adsorption, and ensure that the device is sealed; Step two: connect the dichlorobenzene feeding pipeline, water feeding pipeline, acetic acid feeding pipeline and recovered concentrated acetic acid feeding pipeline to the pipeline connection pipe on the cover, open the automatic control valve for air tightness test, and add dichlorobenzene, acetic acid, water and recovered concentrated acetic acid into the dichlorobenzene storage tank, acetic acid storage tank, water metering tank and recovered acetic acid storage tank respectively; Step three: continuously feed the heating medium such as water or heat conducting oil into the medium inlet pipe to the spiral conveying pipe, the medium flows along the spiral path around the reaction cavity and then flows out from the bottom medium discharge pipe, the target temperature of the heating jacket is set by the temperature control system, and the heat stability is maintained by using heat preservation materials; Step four: start the motor, drive the main stirring paddle and auxiliary stirring paddle to operate through the linkage assembly, the main stirring paddle drives a large amount of material to circulate, forming an overall flow trend, and the auxiliary stirring paddle generates strong shear and turbulence in the local area to finely disperse the material; Step five: after the reaction is completed, the heating medium input is turned off, the temperature of the reaction cavity is reduced to room temperature, the discharge pipe valve is opened, the product is discharged into the subsequent purification equipment, and the cover is disassembled, and the inner wall of the reaction tank and the stirring paddle are cleaned with a cleaning liquid to prepare for the next reaction.

[0016] Compared with the prior art, the present application has the following advantages: 1. In the present application, the motor drives the main stirring paddle on the cover and the multiple auxiliary stirring paddles around it to rotate together through the linkage assembly, the main and auxiliary stirring paddles cooperate to stir the dichlorobenzene, aqueous phase catalyst and organic phase material in the reaction tank from multiple angles and multiple areas, effectively breaking the liquid-liquid and solid-liquid stratification phenomenon, reducing the mass transfer resistance, promoting the material to mix fully, accelerating the reaction rate and making the reaction more complete; at the same time, the heating medium is conveyed in the heating jacket around the reaction cavity through the spiral conveying pipe, the spiral-shaped distribution of the conveying pipe can make the heating medium act uniformly on the outer wall of the reaction cavity, and the heat preservation material between the heating jacket and the spiral conveying pipe reduces heat loss, realizes precise control and uniform distribution of the reaction temperature, avoids local overheating to cause side reactions, thereby reducing the generation of polychlorinated impurities and improving the purity of dichlorobenzene nitrile product, to solve the problems in the background art; 2. In the present application, the pipeline connection pipes are arranged in a circumferential array on the cover and are staggered with the bearing seat, and the automatic control valve is connected to different material pipelines, which can realize multiple functional advantages: first, the circumferential array layout makes the material pipelines uniformly distributed around the center of the reaction tank, ensuring that the material forms a symmetrical flow field in the radial direction of the reaction cavity when added, and cooperating with the stirring device can quickly disperse to the whole system, avoiding local high concentration to cause side reactions, and precisely regulating the feeding time, flow and pressure of each material through the automatic control valve, especially suitable for the multi-component stepwise feeding process in dichlorobenzene nitrile synthesis, avoiding the premature mixing of different materials in the pipeline to cause reaction out of control; 3. This invention enables the main and auxiliary stirring paddles to achieve differentiated motion trajectories under the same motor drive. It establishes overall circulation through the large-diameter main paddle and enhances local turbulence with multi-directional auxiliary paddles, making it particularly suitable for the dispersion and mixing of solid-liquid heterogeneous systems in the synthesis of dichlorobenzonitrile. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the specific structure of the present invention from another perspective; Figure 3 This is a schematic diagram of the specific structure of the present invention from another angle; Figure 4 This is a schematic diagram of the specific structure of the present invention without the cover installed; Figure 5 This is a schematic diagram of the cover connection structure in this invention; Figure 6 This is a schematic diagram of the internal connection structure of the cover body after the top plate is removed in this invention; Figure 7 This invention is for Figure 6 A magnified view of the local structure of A.

[0018] In the diagram: 1. Reaction vessel; 101. Heating jacket; 102. Reaction chamber; 103. Annular groove; 2. Cover; 3. Stirring device; 301. Main stirring paddle; 302. Auxiliary stirring paddle; 303. Motor; 304. Linkage assembly; 3041. Bearing A; 3042. Rotating rod A; 3043. Large gear; 3044. Small gear; 3045. Bearing housing; 3046. Bearing B; 3047. Rotating rod B; 4. Screw conveyor pipe; 5. Support rod; 6. Cast iron counterweight base; 7. Discharge pipe; 8. Medium inlet pipe; 9. Medium outlet pipe; 10. Pipeline connection pipe; 11. Automatic control valve; 12. Rubber; 13. Groove seat; 1301. Through hole; 14. Connecting plate; 15. Protrusion; 16. Screw; 17. Magnet; 18. Iron plate. Detailed Implementation

[0019] Example 1 like Figures 1 to 5As shown, the present application provides a reaction device based on dichloronitrile synthesis, comprising a reaction tank 1, and a cover 2 located at the top end of the reaction tank 1, a heating sandwich 101 is arranged on the reaction tank 1, and a spiral conveying pipe 4 is arranged in the heating sandwich 101 and surrounds the middle reaction cavity 102 of the reaction tank 1, the heating medium (such as water, heat conducting oil, etc.) is conveyed through the spiral conveying pipe 4, the gap between the heating sandwich 101 and the spiral conveying pipe 4 is filled with heat preservation material, the two ends of the spiral conveying pipe 4 are respectively provided with a medium inlet pipe 8 and a medium outlet pipe 9, and the medium inlet pipe 8 extends from the top of the reaction tank 1, and the medium outlet pipe 9 extends from the bottom of the reaction tank 1, the heating medium enters the spiral conveying pipe from the medium inlet pipe 8, flows in the inside, and is finally discharged from the impurity discharge pipe, the reaction device based on dichloronitrile synthesis further comprises: A stirring device 3 is arranged on the cover 2, comprising a main stirring paddle 301 and a plurality of auxiliary stirring paddles 302 surrounding the main stirring paddle 301, a motor 303 is installed at the top end of the cover 2, and the motor 303 drives the main stirring paddle 301 and the auxiliary stirring paddles 302 to rotate together through a linkage assembly 304.

[0020] When the reaction device is used, the motor 303 drives the main stirring paddle 301 on the cover 2 and the plurality of auxiliary stirring paddles 302 surrounding it to rotate together through the linkage assembly 304, the main and auxiliary stirring paddles cooperate to stir the dichlorobenzene, aqueous phase catalyst and organic phase material in the reaction tank 1 at multiple angles and multiple regions, effectively breaking the liquid-liquid, solid-liquid stratification phenomenon, reducing the mass transfer resistance, promoting the material to mix fully, accelerating the reaction rate and making the reaction more complete; at the same time, the heating medium is conveyed in the heating sandwich 101 around the reaction cavity 102 through the spiral conveying pipe 4, the spiral-shaped distribution of the conveying pipe can make the heating medium uniformly act on the outer wall of the reaction cavity 102, and the heat preservation material (such as aerogel felt, slag wool, etc.) between the heating sandwich 101 and the spiral conveying pipe 4 reduces heat loss, realizes accurate control and uniform distribution of the reaction temperature, avoids local overheating to cause side reactions, thereby reducing the generation of polychlorinated impurities and improving the purity of dichloronitrile product.

[0021] The main agitator 301 can be an axial-flow agitator, such as a propeller agitator. This type of agitator enables axial flow of the fluid, resulting in a large flow rate and low head. During the mixing process, it can rapidly propel a large amount of material through circulation, allowing the materials to mix quickly within the reactor and establishing a macroscopic material flow system, providing a good mixing foundation for the entire reaction system. For example, in the early stages of dichlorobenzonitrile synthesis, the rapid mixing of a large amount of material requires this high-flow-rate agitation method. The auxiliary agitator 302 is suitable as a radial agitator, such as a turbine agitator. Turbine agitators can generate radial flow of the fluid, creating strong shear forces and turbulence around the blades, which can effectively break up material clumps and promote microscopic mixing between materials. In the dichlorobenzonitrile synthesis reaction, turbine agitators play a significant role in the dispersion and mixing of solid catalysts and liquid materials, as well as in improving mass and heat transfer efficiency.

[0022] In this way, the main agitator 301 drives the circulation of a large amount of material, forming an overall flow trend; the auxiliary agitator 302 generates strong shear and turbulence in local areas, refining and dispersing the material. The combination of the two ensures both macroscopic uniform distribution of materials in the reactor and thorough mixing at the microscopic level, allowing the materials related to the synthesis of dichlorobenzonitrile to come into more complete contact, accelerating the synthesis reaction rate and improving the reaction conversion rate.

[0023] Furthermore, the bottom of the reaction vessel 1 is connected to the cast iron counterweight base 6 via a support rod 5. The bottom center of the reaction vessel 1 is equipped with a discharge pipe 7 with a valve. Due to its high density, the cast iron counterweight base 6 has a higher weight than bases made of ordinary materials, which can stably support the reaction vessel 1. The support rod 5 supports the reaction vessel 1 for a certain distance, thus leaving space for the discharge pipe 7.

[0024] Example 2 like Figures 1-7 As shown in the figure, this embodiment provides the specific structure of the connecting component in Embodiment 1: the linkage component 304 includes a bearing A3041 embedded and fixed at the top of the cover 2, and a rotating rod A3042 is fixedly connected to the inner ring of the bearing A3041. The drive shaft of the motor 303 is connected to the head of the rotating rod A3042. A large gear 3043 is fixedly connected to the bottom of the rotating rod A3042, and multiple small gears 3044 are meshed on the outer side wall of the large gear 3043. The main stirring paddle 301 is fixed at the bottom center of the large gear 3043, and multiple auxiliary stirring paddles 302 are respectively fixed at the bottom center of the small gears 3044. Multiple bearing seats 3045 are arranged in a circular array on the inner side wall of the cover 2. Each bearing seat 3045 has a bearing B3046 installed inside, and a rotating rod B3047 is fixedly connected to the inner ring of the bearing B3046. The bottom end of the rotating rod B3047 is connected to the small gear 3044.

[0025] When in operation, the transmission shaft of the motor 303 drives the rotation of the rotating rod A 3042, which drives the rotation of the inner ring of the bearing A 3041, which rotates along with the outer ring. The bearing A 3041 rotationally supports the rotating rod A 3042, the gear 3043, and the main stirring paddle 301, and the rotating rod A 3042 transmits power to the gear 3043. The gear 3043, as the driving wheel, drives the surrounding multiple pinions 3044 to rotate in the opposite direction through external meshing. When the pinions 3044 rotate, they drive the rotation of the rotating rod B 3047, which drives the rotation of the inner ring of the bearing B 3046, which rotates along with the outer ring. The bearing B 3046 rotationally supports the rotating rod B 3047, the pinions 3044, and the auxiliary stirring paddle 302. At this time, the gear 3043 and the pinions 3044 form a planetary gear transmission structure. The main stirring paddle 301 is coaxially connected to the gear 3043 and directly obtains the same rotational speed and direction as the gear 3043, generating an axial flow field to realize macroscopic circulation of the material. Each auxiliary stirring paddle 302 is fixed to the bottom of the pinion 3044 and rotates in different directions and speeds (depending on the gear tooth ratio, which can be adjusted according to actual conditions) under the drive of the gear 3043, forming a radial shear flow field to break up material agglomeration. This design enables the main and auxiliary stirring paddles to realize differentiated motion trajectories under the drive of the same motor 303, establishing overall circulation through the large-diameter main paddle and strengthening local turbulence through the multi-directional auxiliary paddles, which is particularly suitable for the dispersion and mixing of the solid-liquid heterogeneous system in the synthesis of dichlorobenzene.

[0026] In this embodiment, the cover 2 is also embedded with pipeline connection pipes 10 arranged in a circumferential array and staggered with the bearing seat 3045, and automatic control valves 11 are installed on the pipeline connection pipes 10. The pipeline connection pipes 10 are connected to dichlorobenzene feeding pipelines, water dropping pipelines, acetic acid feeding pipelines, and recovered concentrated acetic acid feeding pipelines, respectively. The dichlorobenzene feeding pipelines are connected to a dichlorobenzene metering tank, which is connected to a dichlorobenzene storage tank, for accurately delivering dichlorobenzene required for the reaction. The water dropping pipelines are connected to a water metering tank to control the amount and speed of water dropping in the reaction. The acetic acid feeding pipelines are connected to an acetic acid metering tank, which is connected to an acetic acid storage tank, to realize stable supply of acetic acid. The recovered concentrated acetic acid feeding pipelines are connected to a recovered acetic acid storage tank through a transfer pump, and flow meters are installed on the pipelines to accurately measure the amount of added recovered concentrated acetic acid, realizing reasonable utilization of recovered materials.

[0027] The above-mentioned pipeline connecting pipes 10 arranged in a circumferential array on the cover 2 and staggered from the bearing seat 3045, and equipped with automatic control valves 11 to connect different material pipelines, can achieve multiple functional advantages: First, the circumferential array layout ensures that each material pipeline is evenly distributed around the center of the reaction tank 1, ensuring that a symmetrical flow field is formed radially in the reaction chamber 102 when the material is added. With the stirring device 3, it can be quickly dispersed to the entire system, avoiding side reactions caused by excessively high local concentrations. Furthermore, the automatic control valves 11 can precisely regulate the feeding sequence, flow rate, and pressure of each material, which is especially suitable for multi-component stepwise feeding processes in the synthesis of dichlorobenzonitrile (such as adding solvent first and then adding catalyst dropwise), avoiding premature mixing of different materials in the pipelines, which could lead to uncontrolled reaction.

[0028] It should be noted that the cover 2 is also provided with a solid material inlet for adding fixed materials, which is not shown in the figure.

[0029] Example 3 like Figures 1-5 As shown, this embodiment is an improvement on embodiment 1: the top of the reaction vessel 1 is provided with an annular groove 103 for the cover 2 to be inserted. The insertion part of the cover 2 is covered with rubber 12. The cover 2 achieves a sealed connection with the reaction vessel 1 by inserting into the annular groove 103. This is mainly reflected in the fact that the rubber 12 covering layer fills the tiny gap between the groove and the cover 2 by elastic deformation, forming a flexible sealing structure, which effectively prevents the leakage of gas and liquid media in the reaction vessel 1 or the intrusion of external impurities.

[0030] This embodiment also provides a fixing structure between the reaction vessel 1 and the cover 2: the outer side wall of the reaction vessel 1 is fixedly connected with a groove seat 13 on both sides, the top two sides of the cover 2 are connected to the protrusion 15 through the connecting plate 14, and the bottom two sides of the protrusion 15 are fixedly connected with screws 16. The inner bottom wall of the groove seat 13 is provided with through holes 1301 for the screws 16 to pass through. The outer side wall of the screws 16 is threaded with nuts. A magnet 17 is installed in the middle part of the bottom end of the protrusion 15. An iron plate 18 that attracts the magnet 17 is fixedly connected in the middle part of the inner bottom wall of the groove seat 13.

[0031] During installation, align the protrusion 15 on the cover 2 with the groove seat 13 and insert it. At this time, the cover 2 is also partially inserted into the annular groove 103 (the part covered by rubber 12). Simultaneously, the screw 16 at the bottom of the protrusion 15 protrudes from the through hole 1301 on the groove seat 13. The protrusion 15 is pressed against the inner surface of the groove seat 13, so that the magnet 17 and the iron plate 18 come into contact, thereby forming a certain attraction. At this time, combined with the gravity of the cover 2 and its connecting structure, the cover 2 can be relatively and securely fixed to the reaction vessel 1. If the reaction process is too violent, a nut can also be installed on the screw 16 to press against the bottom of the groove seat 13, further securing the cover 2 and the reaction vessel 1. The operator can choose the installation method according to the actual needs.

[0032] The application also provides a method for using the reaction device for synthesizing dichlorobenzene nitrile. Step one: insert the cover 2 into the annular groove 103 at the top end of the reaction tank 1, ensure that the rubber 12 coating fills the gap, and fix the cover 2 by the screw rod 16-nut structure of the groove seat 13 and the convex block 15 and the magnet 17-iron plate 18, to ensure the sealing of the device; Step two: connect the dichlorobenzene feeding pipeline, water feeding pipeline, acetic acid feeding pipeline and recovered concentrated acetic acid feeding pipeline to the pipeline connecting pipe 10 on the cover 2, open the automatic control valve 11 for air tightness test, and add dichlorobenzene, acetic acid, water and recovered concentrated acetic acid into the dichlorobenzene storage tank, acetic acid storage tank, water metering tank and recovered acetic acid storage tank respectively; Step three: continuously input heating medium such as water or heat conducting oil into the medium inlet pipe 8 to the spiral conveying pipe 4, the medium flows along the spiral path around the reaction cavity 102 and then flows out from the bottom medium discharge pipe 9, the target temperature (such as 80-105℃) of the heating sandwich 101 is set by the temperature control system, and the heat stability is maintained by the heat preservation material; Step four: start the motor 303, drive the main stirring paddle 301 and the auxiliary stirring paddle 302 to operate through the linkage assembly 304, the main stirring paddle 301 drives a large amount of material to circulate to form an overall flow trend, and the auxiliary stirring paddle 302 generates strong shearing and turbulence in the local area to finely disperse the material; Step five: after the reaction is completed, close the heating medium input, wait for the temperature of the reaction cavity 102 to drop to room temperature, open the valve of the discharge pipe 7, and discharge the product into the subsequent purification equipment; and disassemble the cover 2, and clean the inner wall of the reaction tank 1 and the stirring paddle with cleaning liquid to prepare for the next reaction.

[0033] The reaction device for synthesizing dichlorobenzene nitrile and the method for using the same have the following advantages: The motor 303 drives the main stirring paddle 301 on the cover 2 and the multiple auxiliary stirring paddles 302 around it to rotate through the linkage assembly 304, the main and auxiliary stirring paddles cooperate to stir the dichlorobenzene, aqueous phase catalyst and organic phase material in the reaction tank 1 at multiple angles and multiple areas, effectively break the liquid-liquid and solid-liquid stratification phenomenon, reduce the mass transfer resistance, promote the material to mix fully, accelerate the reaction rate and make the reaction more complete; at the same time, the heating medium is conveyed in the heating sandwich 101 around the reaction cavity 102 through the spiral conveying pipe 4, the spiral distribution of the conveying pipe can make the heating medium uniformly act on the outer wall of the reaction cavity 102, and the heat preservation material between the heating sandwich 101 and the spiral conveying pipe 4 reduces heat loss, realizes accurate control and uniform distribution of the reaction temperature, avoids local overheating to cause side reactions, thereby reduces the generation of polychlorinated impurities and improves the purity of dichlorobenzene nitrile product; By using the circumferential array arrangement and staggered with the bearing seat 3045 pipeline connecting pipe 10 on the cover 2, and configure automatic control valve 11 to connect different material pipeline, can realize multiple functional advantages: first, the circumferential array layout makes each material pipeline evenly distributed around the center of the reactor 1, to ensure that the material is added in the radial direction of the reaction chamber 102 to form a symmetrical flow field, with the stirring device 3 can be quickly dispersed to the whole system, avoid local concentration too high to cause side reaction, and through the automatic control valve 11 precise control of the feeding time, flow and pressure of each material, especially suitable for dichlorobenzene synthesis in multi-component stepwise feeding process, to avoid different materials in the pipeline mixed in advance to lead to the reaction out of control; Make the main and auxiliary stirring paddle realize differential motion track under the same motor 303 drive, both through the large diameter main paddle to establish the overall circulation, and use the multi-directional auxiliary paddle to strengthen the local turbulent flow, especially suitable for the dispersion mixing of solid-liquid heterogeneous system in dichlorobenzene synthesis.

[0034] The above is only the preferred embodiment of the present application, and does not limit the present application in any form; those skilled in the art can easily implement the present application according to the drawings and the above description; however, those skilled in the art can make some changes, modifications and equivalent changes within the scope of the present application without departing from the technical scheme of the present application; meanwhile, any equivalent changes, modifications and evolution of the above embodiments according to the essential technology of the present application are still within the protection scope of the present application.

Claims

1. A reaction device based on dichlorobenzene synthesis, comprising a reaction tank (1), and a cover (2) located at the top end of the reaction tank (1), characterized in that: The reaction tank (1) is provided with a heating sandwich (101), and a spiral conveying pipe (4) is arranged around the middle reaction cavity (102) of the reaction tank (1) in the heating sandwich (101). The heating medium is conveyed through the spiral conveying pipe (4). The gap between the heating sandwich (101) and the spiral conveying pipe (4) is filled with heat preservation material. The reaction device for synthesizing dichlorobenzene further comprises: The stirring device (3) is arranged on the cover body (2) and comprises a main stirring paddle (301) and a plurality of auxiliary stirring paddles (302) surrounding the main stirring paddle (301). The top end of the cover body (2) is provided with a motor (303), and the motor (303) drives the main stirring paddle (301) and the auxiliary stirring paddles (302) to rotate through a linkage assembly (304).

2. The reaction apparatus based on dichlorobenitrile synthesis according to claim 1, characterized by: The linkage assembly (304) comprises a bearing A (3041) embeddedly fixed at the top end of the cover body (2), and a rotating rod A (3042) is fixedly connected in the inner ring part of the bearing A (3041). The transmission shaft of the motor (303) is connected with the head part of the rotating rod A (3042). The bottom part of the rotating rod A (3042) is fixedly connected with a large gear (3043), and a plurality of small gears (3044) are meshingly connected on the outer side wall of the large gear (3043). The main stirring paddle (301) is fixed at the bottom center part of the large gear (3043), and the plurality of auxiliary stirring paddles (302) are respectively fixed at the bottom center part of the small gears (3044).

3. The reaction apparatus based on dichlorobenzenes synthesis according to claim 2, characterized by: A plurality of bearing seats (3045) are arranged in a circumferential array on the inner side wall of the cover body (2). Bearings B (3046) are arranged in the bearing seats (3045). Rotating rods B (3047) are fixedly connected in the inner ring parts of the bearings B (3046). The bottom ends of the rotating rods B (3047) are connected with the small gears (3044).

4. The reaction apparatus based on dichlorobenitrile synthesis according to claim 1, characterized by: The main stirring paddle (301) is an axial flow type propelling type stirring paddle, and the auxiliary stirring paddles (302) are radial type turbine type stirring paddles.

5. The reaction apparatus based on dichlorobenitrile synthesis according to claim 1, characterized by: The bottom end of the reaction tank (1) is connected with an iron counterweight base (6) through a support rod (5). A discharge pipe (7) provided with a valve is arranged at the bottom center part of the reaction tank (1).

6. The reaction apparatus based on dichlorobenitrile synthesis according to claim 1, characterized by: The two ends of the spiral conveying pipe (4) are respectively provided with a medium inlet pipe (8) and a medium outlet pipe (9). The medium inlet pipe (8) extends from the top of the reaction tank (1), and the medium outlet pipe (9) extends from the bottom of the reaction tank (1).

7. The reaction apparatus based on dichlorobenitrile synthesis according to claim 3, characterized by: A plurality of pipeline connection pipes (10) arranged in a circumferential array and staggered with the bearing seats (3045) are embeddedly fixed on the cover body (2). Automatic control valves (11) are arranged on the pipeline connection pipes (10). The plurality of pipeline connection pipes (10) are respectively connected with dichlorobenzene feeding pipelines, water drop feeding pipelines, acetic acid feeding pipelines and recovered concentrated acetic acid feeding pipelines.

8. The reaction apparatus based on dichlorobenitrile synthesis according to claim 1, characterized by: An annular groove (103) is arranged at the top end of the reaction tank (1) for inserting the cover body (2). The insertion part of the cover body (2) is covered with rubber (12).

9. The reaction apparatus based on dichlorobenitrile synthesis according to claim 8, characterized by: Both sides of the outer side wall of the reaction tank (1) are fixedly connected with groove seats (13), both sides of the top end of the cover body (2) are connected with protrusions (15) through connecting plates (14), and both sides of the bottom end of the protrusions (15) are fixedly connected with screw rods (16), both sides of the inner bottom wall of the groove seat (13) are provided with through holes (1301) for the screw rods (16) to pass through, the outer side wall of the screw rod (16) is threadedly connected with a nut, the bottom end of the protrusion (15) is provided with a magnet (17) at the middle part, and the inner bottom wall of the groove seat (13) is fixedly connected with an iron plate (18) which is attracted to the magnet (17).

10. Use of a reaction apparatus based on the synthesis of dichlorophenylurea according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: Step one: insert the cover body (2) into the annular groove (103) at the top end of the reaction tank (1), ensure that the rubber (12) coating layer fills the gap, and fix the cover body (2) through the screw rod (16)-nut structure of the groove seat (13) and the protrusion (15) and the magnet (17)-iron plate (18) adsorption, to ensure the sealing of the device; Step two: connect the dichlorobenzene feeding pipeline, water dropping pipeline, acetic acid adding pipeline and recovered concentrated acetic acid adding pipeline to the pipeline connecting pipe (10) on the cover body (2) respectively, open the automatic control valve (11) for air tightness test, and add dichlorobenzene, acetic acid, water and recovered concentrated acetic acid into the dichlorobenzene storage tank, acetic acid storage tank, water metering tank and recovered acetic acid storage tank respectively; Step three: continuously input heating medium such as water or heat conducting oil into the medium inlet pipe (8) to the spiral conveying pipe (4), the medium flows along the spiral path around the reaction cavity (102) and then flows out from the bottom medium discharge pipe (9), the target temperature of the heating sandwich (101) is set through the temperature control system, and the thermal stability is maintained by using the heat preservation material; Step four: start the motor (303), drive the main stirring paddle (301) and the auxiliary stirring paddle (302) to operate through the linkage assembly (304), the main stirring paddle (301) drives a large amount of materials to circulate, forming an overall flow trend, and the auxiliary stirring paddle (302) generates strong shear and turbulence in the local area to finely disperse the materials; Step five: after the reaction is completed, the heating medium input is turned off, the temperature of the reaction cavity (102) is reduced to room temperature, the valve of the discharge pipe (7) is opened, the product is discharged into the subsequent purification equipment, and the cover body (2) is disassembled, and the inner wall and the stirring paddle of the reaction tank (1) are cleaned with cleaning liquid to prepare for the next reaction.

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