A low-temperature crystallization device for pesticide intermediates

Abstract

The utility model relates to pesticide intermediate crystallization technical field, especially pesticide intermediate low temperature crystallization device, including low temperature crystallization container, pretreatment jar and cooling medium circulation system, the outer wall of low temperature crystallization container is surrounded and is equipped with main cooling pipeline, be used for circulating cooling medium in main cooling pipeline, the utility model discloses a main cooling pipeline is arranged to the outer wall of low temperature crystallization container, can make the low temperature environment of container inside maintains, provides the condition for the low temperature crystallization of material, and the shunt pipeline that communicates with main cooling pipeline is arranged to the outer wall of pretreatment jar, and the shunt pipeline cooling area is less than main cooling pipeline, can carry out precooling treatment to high temperature material, realizes preliminary cooling, avoids high temperature material directly entering low temperature crystallization container and leads to temperature fluctuation too big, influences crystallization effect, and the circulation mechanism of cooling medium realizes the recycling of cooling medium between main cooling pipeline and shunt pipeline, guarantees the stable supply of cooling medium, makes the cooling process more stable and reliable.

Description

Technical Field

[0001] This utility model relates to the field of pesticide intermediate crystallization technology, and in particular to a low-temperature crystallization device for pesticide intermediates. Background Technology

[0002] In the production of pesticide intermediates, crystallization is a commonly used and crucial separation and purification technique. Through crystallization, high-purity crystalline products can be obtained from solutions containing pesticide intermediates, meeting the stringent requirements for raw material quality in subsequent pesticide synthesis. However, before crystallization, the solution containing intermediates needs to be evaporated and concentrated. After this process, the solution containing pesticide intermediates is often at a high temperature. When the high-temperature solution directly enters the crystallization stage, due to the large temperature difference between the solution temperature and the low-temperature environment required for crystallization, the solution will quickly reach a supersaturated state, causing crystals to precipitate rapidly. This rapid crystallization process results in an excessive number of crystal nuclei and uneven growth rates, ultimately producing crystals with small particle sizes and a wide distribution. This not only affects the appearance and flowability of the product but also increases the operational difficulty and reduces production efficiency in subsequent processes such as filtration and drying.

[0003] To prevent this from happening, the solution is usually gradually cooled to a suitable temperature before low-temperature crystallization. However, the room-temperature cooling efficiency in existing technologies is low, the cooling is slow, which prolongs the production cycle and reduces production efficiency.

[0004] Therefore, based on the above situation, it is necessary to design a low-temperature crystallization device for pesticide intermediates to solve the above problems. Utility Model Content

[0005] This invention provides a low-temperature crystallization device for pesticide intermediates to solve the problems in the prior art.

[0006] The technical problem solved by this utility model is achieved by the following technical solution:

[0007] A low-temperature crystallization device for pesticide intermediates includes a low-temperature crystallization container, a pretreatment tank, and a cooling medium circulation system. The outer wall of the low-temperature crystallization container is surrounded by a main cooling pipe through which a cooling medium circulates, maintaining a low-temperature environment inside the crystallization container to achieve low-temperature crystallization of the material. The pretreatment tank is connected above the low-temperature crystallization container. The output end of the pretreatment tank is equipped with a valve to control the flow of material. The outer wall of the pretreatment tank is surrounded by a branch pipe connected to the main cooling pipe via a connecting pipe. The cooling area of ​​the branch pipe is smaller than that of the main cooling pipe, achieving pre-cooling treatment of the high-temperature material. The input end of the cooling medium circulation mechanism is connected to the input end of the main cooling pipe, and the output end of the cooling medium circulation mechanism is connected to the output end of the branch pipe.

[0008] Preferably, it also includes a pretreatment tank anti-crystallization mechanism, which includes a temperature sensor installed inside the pretreatment tank and a controller electrically connected to the temperature sensor. A second valve is provided on the connecting pipe, and a conveying pipe is provided between the connecting pipe and the cooling medium circulation mechanism. A third valve is provided on the conveying pipe, and both the second and third valves are electrically connected to the controller.

[0009] Preferably, both the low-temperature crystallization container and the pretreatment tank are equipped with a stirring mechanism. The stirring mechanism includes a motor and a stirring rod on the output shaft of the motor. The stirring rod is equipped with a scraper for scraping off the crystals on the inner wall of the low-temperature crystallization container and the pretreatment tank.

[0010] Preferably, both the low-temperature crystallization container and the pretreatment tank are detachably connected to a cover, and the motor is located on the cover.

[0011] Preferably, both the low-temperature crystallization container and the pretreatment tank are provided with insulation material, the main cooling pipe is located between the insulation material and the low-temperature crystallization container, and the branch pipe is located between the pretreatment tank and the insulation material.

[0012] Preferably, the cooling medium circulation mechanism includes a cooling medium tank and a cooling element disposed inside the cooling medium tank, and a water pump is provided on the main cooling pipe connected to the cooling medium tank.

[0013] The beneficial effects of this utility model are as follows: by setting a main cooling pipe on the outer wall of the low-temperature crystallization container, the container can maintain a low-temperature environment, providing conditions for the low-temperature crystallization of materials. The pretreatment tank is equipped with a branch pipe connected to the main cooling pipe on its outer wall, and the cooling area of ​​the branch pipe is smaller than that of the main cooling pipe. This allows for pre-cooling of high-temperature materials, achieving initial cooling and preventing high-temperature materials from directly entering the low-temperature crystallization container, which would cause excessive temperature fluctuations and affect the crystallization effect. At the same time, the cooling medium circulation mechanism realizes the recycling of the cooling medium between the main cooling pipe and the branch pipe, ensuring a stable supply of the cooling medium and making the cooling process more stable and reliable. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0015] Figure 1 A three-dimensional structural schematic diagram provided for this utility model;

[0016] Figure 2A front view structural schematic diagram provided for this utility model;

[0017] Figure 3 A cross-sectional structural schematic diagram provided for this utility model;

[0018] Figure 4 This is a partial structural diagram of the present invention;

[0019] Figure 5 This is a cross-sectional structural diagram of the pretreatment tank in this utility model.

[0020] In the diagram, 1. Low-temperature crystallization container; 2. Main cooling pipe; 3. Pretreatment tank; 4. Valve 1; 5. Diversion pipe; 6. Cooling medium circulation mechanism; 61. Cooling medium tank; 62. Cooling element; 71. Temperature sensor; 72. Controller; 8. Valve 2; 9. Connecting pipe; 10. Delivery pipe; 11. Valve 3; 12. Stirring mechanism; 121. Motor; 122. Stirring rod; 13. Scraper; 14. Cover; 15. Insulation material; 16. Water pump. Detailed Implementation

[0021] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the following description, in conjunction with specific illustrations, further elaborates on this utility model.

[0022] Reference Figures 1-5As shown, a low-temperature crystallization device for pesticide intermediates includes a low-temperature crystallization container 1. A main cooling pipe 2 surrounds the outer wall of the low-temperature crystallization container 1, through which a cooling medium can flow. To facilitate the flow of the cooling medium into the main cooling pipe, a cooling medium circulation mechanism 6 is also included. The output end of the cooling medium circulation mechanism 6 is connected to the input end of the main cooling pipe 2. The cooling medium in the cooling medium circulation mechanism flows into the main cooling pipe 2 to maintain a low-temperature environment inside the low-temperature crystallization container 1, thereby achieving low-temperature crystallization of the material entering the low-temperature crystallization container 1. If the material is a high-temperature solution before entering the low-temperature crystallization container 1, due to the large temperature difference between the solution temperature and the low-temperature environment required for crystallization, the solution will quickly reach a supersaturated state, causing crystals to precipitate rapidly. This rapid crystallization process results in an excessive number of crystal nuclei and uneven growth rates. Therefore, a pretreatment tank 3 is connected above the low-temperature crystallization container 1. The output of the pretreatment tank 3... A valve 4 is provided at the end to control the flow of materials. The material first enters the pretreatment tank 3, and then the cooling medium in the main cooling pipe 2 gradually flows upward under the action of the cooling medium circulation system and enters the diversion pipe 5 surrounding the outer wall of the pretreatment tank 3 through the connecting pipe 9. In order to make the temperature in the pretreatment tank 3 slightly lower than the ambient temperature, the cooling area of ​​the diversion pipe 5 is smaller than that of the main cooling pipe 2. For example, the internal flow area of ​​the diversion pipe 5 is smaller than that of the main cooling pipe 2, and the contact area between the diversion pipe 5 and the pretreatment tank 3 is smaller than that between the main cooling pipe 2 and the low-temperature crystallization container 1. All of these can achieve the above purpose and realize the preliminary pre-cooling treatment of the high-temperature solution. The cooling medium entering the cooling medium circulation mechanism 6 from the output end of the diversion pipe 5 is then cooled and circulated. After a period of pretreatment, the valve 4 is opened so that the solution in the pretreatment tank 3 can gradually precipitate crystals in the low-temperature crystallization container 1, thereby improving the crystallization effect.

[0023] Reference Figure 1 , Figure 2 as well as Figure 5As shown, furthermore, to prevent premature crystallization in the pretreatment tank 3, a pretreatment tank anti-crystallization mechanism is also included. The pretreatment tank anti-crystallization mechanism includes a temperature sensor 71 installed in the pretreatment tank 3 and a controller 72 electrically connected to the temperature sensor 71. During use, the temperature sensor 71 senses the temperature inside the pretreatment tank 3. If this temperature is lower than the set threshold, it indicates that the low temperature will cause the solution to precipitate crystals. At this time, the controller 72 receives the signal from the temperature sensor 71 and transmits the signal to the valve 8 installed on the connecting pipe 9 and electrically connected to the controller 72. In actual use, the valve 8 can be a flow regulating valve, etc., and then the flow rate of the cooling medium inside the diversion pipe 5 is reduced. In order to prevent the flow rate and velocity in the main cooling pipe 2 from decreasing at the same time, a conveying pipe 10 is provided between the connecting pipe 9 and the cooling medium circulation mechanism 6. A valve 11 electrically connected to the controller 72 is provided on the conveying pipe 10. At the same time, the controller 72 controls the valve 11 to open, so that some medium flows from the conveying pipe 10 to the cooling medium circulation mechanism 6.

[0024] Reference Figure 3 , Figure 5 As shown, furthermore, in order to facilitate the stirring of materials in the low-temperature crystallization container 1 and the pretreatment tank 3, and to achieve uniform cooling and crystallization, a stirring mechanism 12 is provided in both the low-temperature crystallization container 1 and the pretreatment tank 3. The stirring mechanism 12 includes a motor 121 and a stirring rod 122 located on the output shaft of the motor 121. When the motor 121 is started, it drives the stirring rod 122 to rotate. At the same time, a scraper 13 is provided on the stirring rod 122. The scraper 13 contacts the inner wall of the low-temperature crystallization container 1 and the pretreatment tank 3 to prevent material residue on the inner wall and to allow the material to circulate within the container, avoiding large local temperature differences. In the pretreatment tank 3, the high-temperature material can quickly exchange heat with the diversion pipe 5 on the outer wall of the pretreatment tank 3 to uniformly reduce the temperature. In the low-temperature crystallization container 1, the material temperature can be uniformly maintained at the low temperature required for crystallization, ensuring the smooth progress of the crystallization process.

[0025] In order to facilitate the disassembly of the stirring mechanism 12 for cleaning the interior of the low-temperature crystallization container 1 and the pretreatment tank 3, a cover 14 is detachably connected to both the low-temperature crystallization container 1 and the pretreatment tank 3. The motor 121 is located on the cover 14. The cover 14 can be detachably connected by means of threads, snap-fit, etc. The cover 14 on the low-temperature crystallization container 1 can be located at the bottom of the low-temperature crystallization container 1 to facilitate the pouring out of crystals and mother liquor. The cover 14 on the pretreatment tank 3 is located at the top of the pretreatment tank 3. After use, the interior of the container can be thoroughly cleaned by removing the cover 14, avoiding problems such as blockage and corrosion caused by the accumulation of residues, and extending the service life of the equipment.

[0026] Reference Figure 1 , Figure 2 , Figure 3 as well as Figure 5 As shown, furthermore, to facilitate the insulation of the interior of the low-temperature crystallization container 1 and the pretreatment tank 3, both the low-temperature crystallization container 1 and the pretreatment tank 3 are equipped with insulation material 15. The cooling pipe is located between the insulation material 15 and the low-temperature crystallization container 1, and the diversion pipe 5 is located between the pretreatment tank 3 and the insulation material 15. The insulation material 15 can be made of polyurethane foam, polystyrene foam, or other materials. The insulation material 15 can effectively reduce the heat exchange between the interior of the low-temperature crystallization container 1 and the pretreatment tank 3 and the external environment, and reduce the rate at which heat is lost to the surrounding environment. For the low-temperature crystallization container 1, it can maintain its internal low-temperature environment, reduce the consumption of cooling medium, and reduce energy consumption. For the pretreatment tank 3, it can prevent the temperature of the pre-cooled material from rising again, ensure the pre-cooling effect, and facilitate the subsequent low-temperature crystallization process. It also reduces heat loss, allowing the cooling medium in the cooling pipe and the diversion pipe 5 to play a more effective role, transferring more cooling energy to the material and improving cooling efficiency.

[0027] Reference Figure 3 As shown, further, in order to enable the cooling medium to be recycled, the cooling medium circulation mechanism 6 includes a cooling medium tank 61 and a cooling element 62 disposed inside the cooling medium tank 61. A water pump 16 is provided on the main cooling pipe 2 connected to the cooling medium tank 61. The cooling element 62 can be a semiconductor refrigerator, cooling coil, etc. The cooling medium tank 61 can store the cooling medium and cool it through the cooling element 62. Then the water pump 16 makes the cooling medium circulate between the main cooling pipe 2, the branch pipe 5 and the cooling medium tank 61, thereby realizing the recycling of the cooling medium and improving the recycling rate of the cooling medium.

[0028] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A low-temperature crystallization apparatus for pesticide intermediates, characterized in that, include; A low-temperature crystallization container (1) is provided with a main cooling pipe (2) surrounding the outer wall of the low-temperature crystallization container (1). The main cooling pipe (2) is used to circulate a cooling medium to maintain a low-temperature environment inside the low-temperature crystallization container (1) and realize low-temperature crystallization of materials. A pretreatment tank (3) is connected above the low-temperature crystallization container (1). The output end of the pretreatment tank (3) is equipped with a valve (4) to control the flow of materials. The outer wall of the pretreatment tank (3) is surrounded by a diversion pipe (5) that is connected to the main cooling pipe (2) through a connecting pipe (9). The cooling area of ​​the diversion pipe (5) is smaller than that of the main cooling pipe (2), so as to achieve pre-cooling treatment of high-temperature materials. Cooling medium circulation mechanism (6), the output end of the cooling medium circulation mechanism (6) is connected to the input end of the main cooling pipe (2), and the input end of the cooling medium circulation mechanism (6) is connected to the output end of the branch pipe (5).

2. The low-temperature crystallization apparatus for pesticide intermediates according to claim 1, characterized in that, It also includes a pretreatment tank anti-crystallization mechanism, which includes a temperature sensor (71) installed in the pretreatment tank (3) and a controller (72) electrically connected to the temperature sensor (71). A second valve (8) is provided on the connecting pipe (9). A conveying pipe (10) is provided between the connecting pipe (9) and the cooling medium circulation mechanism (6). A third valve (11) is provided on the conveying pipe (10). Both the second valve (8) and the third valve (11) are electrically connected to the controller (72).

3. The low-temperature crystallization apparatus for pesticide intermediates according to claim 1, characterized in that, Both the low-temperature crystallization container (1) and the pretreatment tank (3) are equipped with a stirring mechanism (12). The stirring mechanism (12) includes a motor (121) and a stirring rod (122) on the output shaft of the motor (121). The stirring rod (122) is equipped with a scraper (13) for scraping the crystals on the inner wall of the low-temperature crystallization container (1) and the pretreatment tank (3).

4. The low-temperature crystallization apparatus for pesticide intermediates according to claim 3, characterized in that, Both the low-temperature crystallization container (1) and the pretreatment tank (3) are detachably connected to a cover (14), and the motor (121) is located on the cover (14).

5. The low-temperature crystallization apparatus for pesticide intermediates according to claim 1, characterized in that, Both the low-temperature crystallization container (1) and the pretreatment tank (3) are provided with insulation material (15). The main cooling pipe (2) is located between the insulation material (15) and the low-temperature crystallization container (1). The diversion pipe (5) is located between the pretreatment tank (3) and the insulation material (15).

6. The low-temperature crystallization apparatus for pesticide intermediates according to claim 1, characterized in that, The cooling medium circulation mechanism (6) includes a cooling medium tank (61) and a cooling element (62) located inside the cooling medium tank (61). A water pump (16) is provided on the main cooling pipe (2) connected to the cooling medium tank (61).

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