A continuous device for crystallization of chlorfenapyr

Abstract

The present invention belongs to the technical field of chlorfenapyr production, and specifically provides a continuous device for chlorfenapyr crystallization, including a storage tank, the liquid outlet of the storage tank is connected to the liquid inlet of a falling film evaporator, the liquid outlet of the falling film evaporator is connected to a first temporary storage tank, the first temporary storage tank is connected to a condensation crystallizer, the condensation crystallizer is connected to a condensation crystallization kettle, the liquid outlet of the condensation crystallization kettle is connected to the liquid inlet at the top of a particle classification device, the particle classification device includes a shell, a third screen is fixedly arranged on the upper part of the shell, a third discharge port is arranged on the shell on the lower side of the third screen, a second screen is fixedly arranged on the middle part of the shell with a reverse tilt, the screen hole diameter of the second screen is small, a second discharge port is arranged on the shell on the lower side of the second screen, the second discharge port is connected to the condensation crystallization kettle through a pipeline, the third discharge port is connected to the centrifugal separator through a pipeline, and a collection box is arranged at the discharge port of the centrifugal separator. Through the above arrangement, the crystal particle size can be controlled.

Description

Technical Field

[0001] The invention relates to the technical field of chlorfenapyr production, in particular to a continuous device for chlorfenapyr crystallization. Background Art

[0002] Chlorfenapyr (also known as chlorfenapyr) is a new type of pyrrole compound. Chlorfenapyr has received extensive attention and recognition due to its excellent insecticidal and acaricidal activity and unique chemical structure. Chlorfenapyr acts on the mitochondria of insect cells and works through the multifunctional oxidase in the insect body, mainly inhibiting the conversion of adenosine diphosphate (ADP) to adenosine triphosphate (ATP), thereby blocking the oxidative phosphorylation of mitochondria, leading to cell failure and ultimately the death of pests.

[0003] During the application of chlorfenapyr, the crystal particle size of chlorfenapyr will affect its solubility, suspension, dispersibility and biological activity. Too small a particle size may cause it to form an oversaturated state in the solution, increasing the risk of crystal precipitation, thereby affecting the stability of the preparation, while too large a crystal particle size may cause agglomeration or precipitation during storage, affecting the uniformity and use effect of the product. Summary of the invention

[0004] In view of the above-mentioned defects, the present invention provides a continuous device for crystallizing chlorfenapyr, which can make chlorfenapyr crystals in chlorfenapyr solution fully precipitate during the continuous production process of chlorfenapyr crystallization and can control the crystal particle size.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a continuous device for crystallizing chlorfenapyr, comprising a storage tank, the liquid outlet of the storage tank is connected to the liquid inlet of a falling film evaporator through a first transfer pump, the liquid outlet of the falling film evaporator is connected to a first temporary storage tank through a pipeline, the first temporary storage tank is connected to a condensation crystallizer through a pipeline, the condensation crystallizer is connected to a condensation crystallization kettle through a pipeline, the liquid outlet of the condensation crystallization kettle is connected to the liquid inlet at the top of a particle classification device through a second transfer pump, the particle classification device comprises a shell, a third screen is fixedly arranged at an upper part of the shell, a third discharge port is arranged on the shell on a lower side of the third screen, a second screen is fixedly arranged in the middle part of the shell and is inclined in the opposite direction to the third screen, the screen hole diameter of the second screen is smaller than the screen hole diameter of the third screen, a second discharge port is arranged on the shell on the lower side of the second screen, the second discharge port is connected to the condensation crystallization kettle through a pipeline, the third discharge port is connected to a centrifugal separator through a pipeline, and a collecting box is arranged at the discharge port of the centrifugal separator.

[0006] As a further improvement of the present invention, a first discharge port is opened at the bottom of the shell, the first discharge port is connected to the heating mixing kettle through a third material transfer pump, and the liquid outlet of the heating mixing kettle is connected to the first temporary storage tank through a fifth material transfer pump.

[0007] As a further improvement of the present invention, a first concentration detection sensor is provided in the first temporary storage tank, a first temperature detection sensor is provided in the condensation crystallization kettle, and a second concentration detection sensor is provided in the heating mixing kettle.

[0008] As a further improvement of the present invention, the third screen and the second screen both form an angle of 5-8° with the horizontal plane.

[0009] As a further improvement of the present invention, the steam outlet of the falling film evaporator is connected to the first air inlet of the first condenser through a pipeline, and the water outlet of the first condenser is connected to the mother liquid collection tank.

[0010] As a further improvement of the present invention, the first condenser is further provided with a second air inlet, and the air outlet provided on the top of the heating mixing kettle is connected to the second air inlet of the first condenser.

[0011] As a further improvement of the present invention, a one-way valve is provided at the second air inlet.

[0012] As a further improvement of the present invention, a fourth material transfer pump is provided at the liquid discharge port of the centrifugal separator, and the centrifugal separator is connected to the mother liquid collection tank through the fourth material transfer pump pipeline.

[0013] As a further improvement of the present invention, a third collecting hopper is fixedly connected to the outside of the third discharge port, and the third collecting hopper is arranged to be inclined and contracted, and the end of the third collecting hopper is contracted to a semicircular shape that can be directly sleeved with a pipeline.

[0014] As a further improvement of the present invention, a second collecting hopper having the same structure as the third collecting hopper is fixedly connected to the outside of the second discharge port.

[0015] Beneficial effects of the present invention:

[0016] 1. By setting up a particle grading device, the particles condensed by the condensation crystallizer and the condensation crystallization kettle through graded cooling can be screened and divided into three grades according to the different sizes of the particles. The particles that meet the standard size are centrifuged as products to obtain the final product, and the medium-sized particles are recovered as crystal seeds and automatically transported to the condensation crystallization kettle for secondary condensation and crystallization to grow into the final product that meets the standard. The particles with smaller diameters are eliminated by fine crystals through a heated mixing kettle, and are condensed by graded cooling in the condensation crystallizer and the condensation crystallization kettle again. This process can make the obtained chlorfenapyr crystal size grow to meet the use standard, and can ensure that the chlorfenapyr crystals that do not meet the size standard can be crystallized again, so that the chlorfenapyr can be fully precipitated.

[0017] 2. By setting a first concentration detection sensor, a second concentration detection sensor and a first temperature detection sensor, the solution concentration can be monitored at all times, so as to adjust the condensation temperature of the condensation crystallization kettle, ensure that the crystallization rate of the chlorfenapyr crystals is always fast during the condensation crystallization process, and can further enhance the precipitation of the chlorfenapyr crystals. At the same time, by detecting the concentration through the concentration detection sensor, the heating temperature of the falling film evaporator and the heating mixing kettle can be adjusted, so that the concentrated chlorfenapyr solution can be at a higher saturation, which is convenient for condensation and precipitation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of a continuous device for crystallization of chlorfenapyr of the present invention;

[0019] Figure 2 It is an axonometric diagram of the installation structure of the particle classification device;

[0020] Figure 3 It is a schematic diagram of the internal structure of the particle classification device;

[0021] Figure 4 It is a schematic diagram of the third screen structure.

[0022] In the figure: 1-storage tank, 2-first transfer pump, 3-falling film evaporator, 4-first temporary storage tank, 40-first concentration detection sensor, 5-condensation crystallizer, 6-condensation crystallization kettle, 60-first temperature detection sensor, 7-second transfer pump;

[0023] 8-particle classification device, 80-first feed port, 81-third discharge port, 82-second discharge port, 83-first discharge port, 84-second collecting hopper, 85-third collecting hopper, 86-third screen slot, 87-third screen frame, 88-third screen surface, 89-second screen slot, 810-second screen frame, 811-second screen surface;

[0024] 9-the third material transfer pump, 10-the stand, 11-the centrifugal separator, 12-the collecting box, 13-the fourth material transfer pump, 14-the mother liquor collecting tank, 15-the one-way valve, 16-the first condenser, 17-the heating mixing kettle, 170-the second concentration detection sensor, 18-the fifth material transfer pump. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings. It should be understood that the specific examples described herein are only used to explain the present invention and are not intended to limit the present invention. The directional terms mentioned in the following embodiments, such as: up, down, left, right, front or back, etc., are only referenced to the directions of the accompanying drawings. Therefore, the directional terms used are used to illustrate and are not used to limit the present invention. In addition, in all embodiments, the same figure numerals represent the same elements.

[0026] See also Figures 1 to 4 The present invention provides a continuous device for crystallization of chlorfenapyr, comprising a storage tank 1, a first transfer pump 2 is arranged at the discharge pipe of the storage tank 1, the feed end of the first transfer pump 2 is connected to the discharge pipe of the storage tank 1, and the discharge end of the first transfer pump 2 is connected to the liquid inlet of the falling film evaporator 3 through a pipeline. The steam outlet of the falling film evaporator 3 is connected to the first air inlet of the first condenser 16 through a pipeline, and the water outlet of the first condenser 16 is connected to the mother liquor collection tank 14. The discharge port of the falling film evaporator 3 is connected to the liquid inlet of the first temporary storage tank 4. A first concentration detection sensor 40 is arranged in the first temporary storage tank 4, which can detect the concentration of the solution output by the falling film evaporator 3.

[0027] As a further explanation of this embodiment, the storage tank 1 contains a chlorfenapyr solution, which can be transported to the falling film evaporator 3 through the first transfer pump 2. The falling film evaporator 3 has a heating function, which can further heat the chlorfenapyr solution to further increase the saturation of chlorfenapyr in the chlorfenapyr solution. The water evaporated by heating the falling film evaporator 3 is discharged from the steam outlet of the falling film evaporator 3 into the first condenser 16, and then condensed into liquid water by the first condenser 16 and collected in the mother liquor collection tank 14.

[0028] A solenoid valve is provided at the liquid outlet of the first temporary storage tank 4, and the liquid outlet of the first temporary storage tank 4 is connected to the liquid inlet of the condensation crystallizer 5 through a pipeline, and the discharge port of the condensation crystallizer 5 is connected to the first inlet of the condensation crystallization kettle 6. A jacket is provided on the outside of the condensation crystallization kettle 6, and the jacket is circulated and connected to a refrigeration cycle machine (which is an existing device). A first temperature detection sensor 60 is provided in the condensation crystallization kettle 6 for monitoring the condensation temperature inside the condensation crystallization kettle 6. A second transfer pump 7 is provided at the discharge port of the condensation crystallization kettle 6, and the condensation crystallization kettle 6 is connected to the particle classification device 8 through the second transfer pump 7. The feed end of the second transfer pump 7 is connected to the discharge port of the condensation crystallization kettle 6, and the discharge end of the second transfer pump 7 is connected to the first feed port 80 of the particle classification device 8 through a pipeline.

[0029] As a further explanation of this embodiment, the first concentration detection sensor 40 in the first temporary storage tank 4 can detect the concentration of the chlorfenapyr solution therein, and continuously adjust its condensation temperature according to the concentration of the chlorfenapyr solution to ensure that the supersaturation of the chlorfenapyr solution in the condensation crystallization kettle 6 is relatively stable, so that the crystallization rate and precipitation amount are both high. At the same time, the first concentration detection sensor 40 can also adjust the heating temperature of the falling film evaporator 3 by detecting the concentration to achieve control of the solution concentration in the first temporary storage tank 4.

[0030] The particle classification device 8 is fixedly connected to the top of the stand 10, and the stand 10 is located on one side of the condensation crystallization kettle 6. The particle classification device 8 includes a shell, and a first feed port 80 is provided on the top of the shell. A third screen slot 86 is obliquely opened in the upper part of the shell, and a third screen is fixedly connected in the third screen slot 86. The third screen is also obliquely arranged along the third screen slot 86, and the third screen is at an angle of 5-8° with the horizontal plane. The third screen includes a third mesh frame 87 and a third mesh surface 88. The third mesh surface 88 is a plate-like open hole structure, and the third mesh surface 88 is fixedly connected to the inside of the third mesh frame 87. Both sides of the third mesh frame 87 are opened, and the opening is located on the lower inclined side during installation. A third discharge port 81 is provided on a lower inclined side of the outer shell near the third mesh frame 87, and a third collecting hopper 85 is provided outside the third discharge port 81. The third collecting hopper 85 is inclined in a hopper shape, and is contracted toward the end away from the outer shell. The end portion of the third collecting hopper 85 is semicircular and can be externally sleeved with a pipe.

[0031] A second screen slot 89 is obliquely provided in the middle of the housing, and the second screen slot 89 and the third screen slot 86 are obliquely arranged in different directions. A second screen is fixedly connected in the second screen slot 89, and the second screen is obliquely arranged along the second screen slot 89, and the second screen is at an angle of 5-8° with the horizontal plane. The second screen includes a second mesh frame 810 and a second mesh surface 811, and the second mesh surface 811 is a plate-shaped open hole structure, and the mesh aperture on the second mesh surface 811 is smaller than the mesh aperture of the third mesh surface 88, and the second mesh surface 811 is fixedly connected to the inside of the second mesh frame 810. Both sides of the second mesh frame 810 are open, and the opening is located on the lower inclined side during installation. A second discharge port 82 is provided on the lower inclined side of the outer shell close to the second net frame 810, and a second collecting hopper 84 is provided outside the second discharge port 82. The second collecting hopper 84 is inclined in a hopper shape, and is contracted toward the end away from the outer shell. The end portion of the second collecting hopper 84 is semicircular and can be externally sleeved with a pipe.

[0032] The lower part of the shell shrinks from top to bottom toward the middle, and the first discharge port 83 is provided at the bottom of the shrinkage. The particle classification device 8 is located at the top of the stand 10, the second discharge port 82 of the particle classification device 8 is located on the side close to the condensation crystallization kettle 6, the end of the second collecting hopper 84 is located obliquely above the second feed port of the condensation crystallization kettle 6, and the second collecting hopper 84 is connected to the second inlet of the condensation crystallization kettle 6 through a pipe sleeved at the end.

[0033] As a further explanation of this embodiment, the chlorfenapyr crystals of different particle sizes obtained by condensation in the condensation crystallization kettle 6 can be transported to the particle grading device 8 through the second transfer pump 7, and the solid-liquid mixed condensation crystallization product enters the particle grading device 8 from the first feed port 80. The chlorfenapyr crystals with larger particles cannot pass through the sieve holes on the third sieve, and flow out from the third collecting hopper 85 along the inclined third sieve, while the chlorfenapyr crystals with smaller particles flow through the third sieve together with the dissolved liquid, and are screened twice by the second sieve. The chlorfenapyr crystals with moderate particles flow out from the end of the second collecting hopper 84 along the inclined second sieve, and enter the condensation crystallization kettle 6 from the second inlet as crystal seeds for induced crystallization, while the chlorfenapyr crystals with very small particles pass through the second sieve together with the dissolved liquid and flow out from the first discharge port 83.

[0034] A third material transfer pump 9 is provided at the first material discharge port 83 , a feed end of the third material transfer pump 9 is connected to the first material discharge port 83 of the particle classification device 8 , and a discharge end of the third material transfer pump 9 is connected to the heating mixing kettle 17 through a pipeline.

[0035] A second concentration detection sensor 170 is provided inside the heating mixing kettle 17, which is used to detect the concentration of the secondary dissolved chlorfenapyr solution generated in the heating mixing kettle 17. An air outlet is provided on the top of the heating mixing kettle 17, and the air outlet is connected to the second air inlet of the first condenser 16 through a pipeline, and a one-way valve 15 is provided at the second air inlet. A fifth transfer pump 18 is provided at the liquid outlet of the heating mixing kettle 17, and the feed end of the fifth transfer pump 18 is connected to the liquid outlet of the heating mixing kettle 17, and the discharge end of the fifth transfer pump 18 is connected to the second liquid inlet of the first temporary storage tank 4 through a pipeline.

[0036] As a further explanation of this embodiment, the first discharge port 83 of the particle classification device 8 can flow out the chlorfenapyr crystal dissolution liquid, which contains some tiny particles of chlorfenapyr crystals. This crystal cannot be used as a product, and it cannot be used as a crystal seed to induce crystallization. Therefore, it is necessary to eliminate fine crystals, dissolve it through the heating mixing kettle 17, and increase the concentration. The concentration of the secondary dissolution is detected by the second concentration detection sensor 170 to ensure that the concentration of the chlorfenapyr crystal stock solution obtained by the secondary dissolution is consistent with the concentration of the solution in the first temporary storage tank 4. The gas evaporated during the concentration process enters the first condenser 16 through the gas outlet at the top of the heating mixing kettle 17, and is re-liquefied into a liquid mother liquor by cooling and enters the mother liquor collection tank 14.

[0037] The third discharge port 81 of the particle classification device 8 is located above the feed port of the centrifugal separator 11, and the third discharge port 81 is connected to the feed port of the centrifugal separator 11 through an oblique pipeline. A collection box 12 is provided below the discharge port of the centrifugal separator 11 for collecting the crystallized material separated by the centrifugal separator 11. A fourth transfer pump 13 is provided at the discharge port of the centrifugal separator 11, and the feed end of the fourth transfer pump 13 is connected to the discharge port of the centrifugal separator 11, and the discharge end of the fourth transfer pump 13 is connected to the mother liquid collection tank 14 through a pipeline.

[0038] As a further explanation of this embodiment, the third discharge port 81 of the particle grading device 8 can output cypermethrin crystals with a qualified particle size, but the output cypermethrin crystals still have crystallization dissolving liquid attached to them. The crystallization dissolving liquid and the cypermethrin crystals can be further centrifuged and separated by the centrifuge 11. The separated crystallization dissolving liquid is transported to the mother liquor collection tank 14 through the fourth transfer pump 13, and the cypermethrin crystals with a qualified particle size enter the aggregate box 12 to wait for subsequent processing.

[0039] The working principle and use process of this embodiment:

[0040] The chlorfenapyr solution in the storage tank 1 is transported to the falling film evaporator 3 through the first transfer pump 2, and is thermally concentrated by the falling film evaporator 3 to further increase its concentration and increase the supersaturation of chlorfenapyr in the solution. The highly saturated chlorfenapyr solution is then transported to the first temporary storage tank 4, and then enters the condensation crystallizer 5 and the condensation crystallization kettle 6. The temperature in the condensation crystallizer 5 is higher than the temperature in the condensation crystallization kettle 6. This step is graded cooling and condensation, which can make the chlorfenapyr crystals precipitate more fully. In this process, the final crystallization temperature in the condensation crystallization kettle 6 is continuously adjusted according to the concentration of the solution in the first temporary storage tank 4 to ensure that the precipitation rate and precipitation amount of chlorfenapyr are at the optimal temperature.

[0041] The crystals precipitated in the condensation crystallization kettle 6 enter the particle classification device 8 through the second material transfer pump 7, and the chlorfenapyr crystals obtained by the crystallization are classified by the particle classification device 8. The chlorfenapyr crystals with particle sizes that meet the standards enter the centrifuge 11 from the third discharge port 81 for centrifugal separation. The chlorfenapyr crystals with smaller particle sizes can be used as crystal seeds to induce crystallization to make them grow further, while the chlorfenapyr crystals with extremely small particle sizes need to be refined and eliminated. They are transported to the heating mixing kettle 17 through the third material transfer pump 9 for secondary dissolution. During the dissolution process, the concentration of the chlorfenapyr after heating and dissolution is detected by the second concentration detection sensor 170. The concentration of the chlorfenapyr in the solution is further increased by controlling the temperature of the heating mixing kettle 17, so that its concentration is basically consistent with the concentration in the first temporary storage tank 4, and then transported to the first temporary storage tank 4 for re-condensation and crystallization. At the same time, the gas generated by the falling film evaporator 3 concentration and the heating mixing kettle 17 is transported to the first condenser 16, liquefied into a crystallization solution by the first condenser 16, and can be dissolved and used again.

[0042] The above are only preferred implementations of the present invention. The protection scope of the present invention is not limited to the above implementation measures. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A continuous device for crystallization of chlorfenapyr, characterized in that: The invention comprises a storage tank (1), wherein the liquid outlet of the storage tank (1) is connected to the liquid inlet of a falling film evaporator (3) through a first material transfer pump (2), the liquid outlet of the falling film evaporator (3) is connected to a first temporary storage tank (4) through a pipeline, the first temporary storage tank (4) is connected to a condensation crystallizer (5) through a pipeline, the condensation crystallizer (5) is connected to a condensation crystallizer (6) through a pipeline, the liquid outlet of the condensation crystallizer (6) is connected to the liquid inlet at the top of a particle classification device (8) through a second material transfer pump (7), the particle classification device (8) comprises a shell, a third screen is fixedly arranged at an inclined position in the upper part of the shell, a third discharge port (81) is arranged on the shell on the lower side of the third screen, a second screen is fixedly arranged in the middle part of the shell and is inclined in the opposite direction to the third screen, the screen hole diameter of the second screen is smaller than the screen hole diameter of the third screen, A second discharge port (82) is provided on the outer shell on the lower side of the second screen, the second discharge port (82) is connected to the condensation crystallization kettle (6) through a pipeline, the third discharge port (81) is connected to the centrifugal separator (11) through a pipeline, the centrifugal separator (11) is provided with a collecting box (12) at the discharge port, a first discharge port (83) is provided at the bottom of the outer shell, the first discharge port (83) is connected to the heating mixing kettle (17) through a third material transfer pump (9), the liquid outlet of the heating mixing kettle (17) is connected to the first temporary storage tank (4) through a fifth material transfer pump (18), the first temporary storage tank (4) is provided with a first concentration detection sensor (40), the condensation crystallization kettle (6) is provided with a first temperature detection sensor (60), and the heating mixing kettle (17) is provided with a second concentration detection sensor (170).

2. The continuous device for crystallization of chlorfenapyr according to claim 1, characterized in that: The third screen and the second screen both form an angle of 5-8° with the horizontal plane.

3. The continuous device for crystallization of chlorfenapyr according to claim 1, characterized in that: The steam outlet of the falling film evaporator (3) is connected to the first air inlet of the first condenser (16) through a pipeline, and the water outlet of the first condenser (16) is connected to the mother liquid collection tank (14).

4. The continuous device for crystallization of chlorfenapyr according to claim 3, characterized in that: The first condenser (16) is also provided with a second air inlet, and the air outlet provided on the top of the heating mixing kettle (17) is connected to the second air inlet of the first condenser (16).

5. The continuous device for crystallization of chlorfenapyr according to claim 4, characterized in that: A one-way valve (15) is provided at the second air inlet.

6. The continuous device for crystallization of chlorfenapyr according to claim 1, characterized in that: A fourth material transfer pump (13) is provided at the liquid discharge port of the centrifugal separator (11), and the centrifugal separator (11) is connected to the mother liquid collection tank (14) through a pipeline of the fourth material transfer pump (13).

7. The continuous device for crystallization of chlorfenapyr according to claim 1, characterized in that: A third material collecting hopper (85) is fixedly connected to the outside of the third material discharge port (81), and the third material collecting hopper (85) is arranged to be inclined and contracted, and the end of the third material collecting hopper (85) is contracted into a semicircular shape that can be directly sleeved with a pipeline.

8. The continuous device for crystallizing chlorfenapyr according to claim 7, characterized in that: A second material collecting hopper (84) having the same structure as the third material collecting hopper (85) is fixedly connected to the outside of the second material discharge port (82).

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