Diquat dichloride preparation crystallization separation equipment and separation method

Abstract

The invention discloses a diquat dichloride preparation crystallization separation device and a separation method, and relates to the field of diquat dichloride filtration. The device comprises an outer cylinder, a filter cylinder is coaxially fixed on the outer cylinder and an inner cylinder, a separation gap is formed between the outer cylinder and the filter cylinder, a feed port is connected to the outer cylinder, the feed port is used to conduct materials into the separation gap, a discharge port is provided at the bottom of the filter cylinder, a negative pressure pump is connected to the discharge port, the negative pressure pump sucks the discharge port to generate negative pressure in the filter cylinder, liquid materials in the separation gap pass through the filter cylinder and are discharged from the discharge port, so that particulate materials are retained in the separation gap, and a spiral plate is arranged in the separation gap. The invention separates and filters diquat dichloride particles by means of negative pressure, and while filtering, diquat dichloride particles adsorbed on the surface of the filter cylinder are scraped off by a rotating spiral plate and conducted upward for collection, so that the filter cylinder is kept with good permeability, and efficient continuous crystallization separation of diquat dichloride particles is achieved.

Description

Technical Field

[0001] The invention relates to the field of diquat dichloride filtration, and in particular to diquat dichloride preparation, crystallization and separation equipment and a separation method. Background Art

[0002] Diquat dichloride is an important pesticide ingredient. The purity of diquat dichloride directly affects the quality of pesticide products. In the process of preparing diquat dichloride using pyridine as a raw material, crude diquat dichloride can be obtained through coupling reaction. In order to ensure the purity of diquat dichloride, the crude diquat dichloride needs to be dissolved and recrystallized, which can remove impurities in diquat dichloride to obtain high-purity diquat dichloride.

[0003] After the crude product of diquat dichloride is dissolved and filtered for impurities, the temperature is lowered and crystallized to precipitate diquat dichloride. Since the crystal size of diquat dichloride is small, it is necessary to filter and separate the diquat dichloride in the solvent by means of pressurization. During the separation process, the diquat dichloride particles are easy to aggregate and clog the filtration part, which greatly reduces the efficiency of continuous separation and may even cause the separation work to stagnate. Summary of the invention

[0004] In order to make up for the deficiencies of the prior art, the present invention aims to provide a crystallization separation device and a separation method for preparing diquat dichloride, which are used to solve the problem of easy blockage in the filtration part during the traditional process of adding filtration to separate diquat dichloride.

[0005] In order to solve the problems of the prior art, the technical solution of the present invention is as follows:

[0006] The crystallization separation equipment for preparing diquat dichloride salt comprises: an outer cylinder, a filter cylinder is coaxially fixed to the inner cylinder of the outer cylinder, a separation gap is formed between the outer cylinder and the filter cylinder, the outer cylinder is connected with a feed port, the feed port is used to conduct materials into the separation gap, the bottom of the filter cylinder is provided with a discharge port, the discharge port is connected with a negative pressure pump, the negative pressure pump sucks the discharge port to generate negative pressure in the filter cylinder, the liquid material in the separation gap passes through the filter cylinder and is discharged from the discharge port, so that the particulate material is retained in the separation gap, a spiral plate is arranged in the separation gap, the inner and outer edges of the spiral plate slide in contact with the filter cylinder and the outer cylinder respectively, the top of the spiral plate is connected with a driving component, the top of the outer cylinder is provided with a material receiving component, the spiral plate is driven to rotate by the driving component, so that the spiral plate scrapes the particulate material on the surface of the filter cylinder and conducts it upward to the material receiving component.

[0007] Preferably, the driving assembly comprises a motor, a rotating sleeve is rotatably provided on the top periphery of the filter cartridge, the output shaft of the motor is transmission-connected to the rotating sleeve via a transmission wheel assembly, and the spiral plate is fixedly connected to the rotating sleeve.

[0008] Preferably, the transmission wheel includes an active conical wheel, a driven conical wheel and a roller, a plunger body is vertically slidably arranged on the upper part of the interior of the filter cartridge, a spring is connected to the plunger body for applying an upward elastic force to the plunger body, a shaft rod is fixed to the plunger body, the shaft rod passes through the filter cartridge upward, and the roller is rotatably installed on the top of the shaft rod, the active conical wheel and the driven conical wheel are located on both sides of the roller and squeeze and contact the roller, and the generatrixes of the active conical wheel, the driven conical wheel and the roller are both vertical lines, the top opening of the rotating sleeve has a rough surface, the driven conical wheel is squeezed and contacted with the rough surface, the output shaft of the motor is connected to the active conical wheel, the small diameter end of the active conical wheel is upward, and the small diameter end of the driven conical wheel is downward.

[0009] Preferably, the roller includes a core barrel, which is rotatably arranged on the outside of the shaft through a bearing, a bottom plate is fixed to the bottom of the core barrel, a top plate is sleeved on the top of the core barrel, a rubber tube is connected between the top plate and the bottom plate, and a nut is connected to the external thread of the core barrel, which is used to press down the top plate so that the top plate and the bottom plate squeeze the rubber tube to deform and expand outward.

[0010] Preferably, a carrier plate is slidably arranged at the lower part of the filter cartridge, a spring for elastically squeezing the plunger body upward is arranged between the plunger body and the carrier plate, a stud is threaded through the bottom of the filter cartridge, and the stud presses upward against the carrier plate for positioning the height of the carrier plate.

[0011] Preferably, the material receiving assembly comprises a ring box, which is fixed at the periphery of the top opening of the outer barrel, and a plurality of through openings are provided on the bottom surface of the ring box, and a material barrel is connected below the through openings.

[0012] Preferably, a plurality of scrapers are fixed around the rotating sleeve, the scrapers being used to scrape the inner bottom surface of the ring box, the scrapers being arranged obliquely to the radial line of the ring box, and the inclination directions of adjacent scrapers are opposite.

[0013] Preferably, the barrel is threadedly connected to the through port.

[0014] Preferably, the cross section of the spiral plate is inclined downward at one end close to the outer cylinder.

[0015] A diquat dichloride separation method based on the diquat dichloride preparation crystallization separation equipment, the specific steps are as follows:

[0016] A. The solvent containing diquat dichloride salt particles is continuously introduced into the separation gap through the feed port, and the negative pressure pump is turned on to suck the discharge port, so that negative pressure is generated inside the filter cartridge. The solvent passes through the filter cartridge and is discharged from the discharge port, and the diquat dichloride salt particles are retained in the separation gap;

[0017] B. The spiral plate is driven to rotate by the driving component. The spiral plate scrapes off the diquat dichloride salt particles adsorbed on the outside of the filter cartridge and conducts them upward, so that the diquat dichloride salt particles fall into the receiving component and are collected, thereby preventing the diquat dichloride salt particles from clogging the filter cartridge.

[0018] Compared with the prior art, the advantages of the present invention are as follows:

[0019] 1. The present invention separates and filters diquat dichloride salt particles by means of negative pressure. During the filtration, the diquat dichloride salt particles adsorbed on the surface of the filter cartridge are scraped off by a rotating spiral plate and transferred upward for collection, thereby maintaining good permeability of the filter cartridge and realizing efficient continuous crystallization separation of diquat dichloride salt particles.

[0020] 2. The present invention changes the negative pressure intensity in the filter cartridge as the permeability of the filter cartridge surface changes, thereby changing the height of the roller, changing the position where the roller contacts the active conical wheel and the driven conical wheel, and is used to adaptively adjust the rotation speed of the spiral plate, reduce the turbulence effect of the spiral plate on the filtering work, and dynamically adjust the scraping efficiency in time according to the blockage condition of the filter cartridge surface to ensure that the filter cartridge has good permeability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall external structure of the present invention.

[0022] Figure 2 It is a schematic diagram of the overall cross-sectional structure of the present invention.

[0023] Figure 3 It is a schematic diagram of the scraper distribution structure of the present invention.

[0024] Figure 4 This is one of the schematic diagrams of the connection structure between the spiral plate and the rotating sleeve of the present invention.

[0025] Figure 5 This is the second schematic diagram of the connection structure between the spiral plate and the rotating sleeve of the present invention.

[0026] Figure 6 It is a schematic diagram of the roller structure of the present invention.

[0027] Figure 7 It is a schematic diagram of the roller transmission variation structure of the present invention.

[0028] Figure numerals: 1. outer cylinder; 11. feed port; 2. filter cylinder; 21. discharge port; 3. spiral plate; 4. ring box; 41. through port; 42. barrel; 43. scraper; 5. plunger body; 51. shaft rod; 52. carrier plate; 53. stud; 6. roller; 61. core cylinder; 62. bottom plate; 63. top plate; 64. nut; 65. rubber cylinder; 7. motor; 71. active conical wheel; 72. driven conical wheel; 8. negative pressure pump; 9. rotating sleeve; 91. rough surface. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0030] The diquat dichloride preparation crystallization separation equipment is composed of a basic filtration separation structure, a material blocking separation structure, a material receiving component and a driving component;

[0031] like Figure 1 , Figure 2 As shown, the basic filtering and separation structure includes an outer cylinder 1 and a filter cartridge 2. The outer cylinder 1 is made of stainless steel. The top of the outer cylinder 1 is open and the interior is a cylindrical chamber. The filter cartridge 2 is cylindrical as a whole. The lower 2 / 3 of the filter cartridge 2 is a filtering surface, and the upper 1 / 3 is a smooth plate surface. The filter cartridge 2 is coaxially arranged in the outer cylinder 1. The bottom of the filter cartridge 2 is fixed to the outer cylinder 1, and a discharge port 21 is provided through the bottom surface of the filter cartridge 2. The top of the filter cartridge 2 is higher than the top of the outer cylinder 1, and a separation gap is formed between the outer cylinder 1 and the filter cartridge 2. The feed port 11 passes through the separation gap from the side of the outer cylinder 1, and the feed end of the negative pressure pump 8 is connected to the discharge port 21.

[0032] like Figure 2 As shown, the blocking material separation structure includes a spiral plate 3, which is arranged in the separation gap, the inner edge of the spiral plate 3 is in sliding contact with the outer wall of the filter cartridge 2, the outer edge of the spiral plate 3 is in sliding contact with the inner wall of the outer cartridge 1, and the extension height of the spiral plate 3 is higher than the top opening of the outer cartridge 1;

[0033] like Figure 2 As shown, the material receiving assembly includes a ring box 4, which has a cylindrical inner cavity. The bottom surface of the ring box 4 passes through the top opening of the outer cylinder 1 and is fixed to the periphery of the top opening of the outer cylinder 1. The inner bottom surface of the ring box 4 is in a sunken state at the periphery of the top opening of the outer cylinder 1 to form an annular material channel. A plurality of through openings 41 that pass through the annular material channel are provided on the bottom surface of the ring box 4, and a material cylinder 42 is connected below the through openings 41. The top of the filter cartridge 2 passes through the top surface of the ring box 4. The rotating sleeve 9 is rotatably arranged between the top surface of the ring box 4 and the filter cartridge 2 through a sealing bearing, so that the separation gap and the inside of the ring box 4 form a relatively closed space. The top of the spiral plate 3 is fixedly connected to the rotating sleeve 9, and the rotating sleeve 9 is connected to the driving assembly.

[0034] The solvent with diquat dichloride salt particles is continuously introduced into the separation gap from the feed port 11, and the negative pressure pump 8 is turned on to suck the discharge port 21, so that negative pressure is generated in the filter cartridge 2. The solvent in the separation gap enters the filter cartridge 2 and is sucked out from the discharge port 21, and the diquat dichloride salt particles are retained in the separation gap. The diquat dichloride salt particles are adsorbed on the outer wall of the filter cartridge 2 under the action of negative pressure. At this time, the driving component is turned on to drive the rotating sleeve 9 and the spiral plate 3 to rotate. The spiral plate 3 will peel off the diquat dichloride salt particles adsorbed on the outer surface of the filter cartridge 2, and conduct the diquat dichloride salt upward to the top of the outer cylinder 1. Then the diquat dichloride salt particles fall into the annular material channel, and then fall into the material cylinder 42 through the through port 41 to be collected. The filter cartridge 2 maintains good permeability through the scraping of the spiral plate 3.

[0035] like Figure 2 As shown, the cross section of the spiral plate 3 is inclined downward at one end close to the outer cylinder 1, and the diquat dichloride salt particles conducted upward by the spiral plate 3 will move toward the edge of the spiral plate 3. When reaching the top of the outer cylinder 1, the diquat dichloride salt particles can fall into the annular material channel in time, avoiding excessive adhesion of the material on the surface of the spiral plate 3.

[0036] The barrel 42 is threadedly connected to the through port 41, so that the barrel 42 can be removed later to take out the crude diquat dichloride salt for drying.

[0037] like Figure 3 , Figure 4 , Figure 5 As shown, a plurality of scrapers 43 are fixed around the rotating sleeve 9. The scrapers 43 are inclined with respect to the radial line of the ring box 4, and the inclination directions of adjacent scrapers 43 are opposite. When the rotating sleeve 9 rotates, the scrapers 43 are driven to scrape the annular material channel, so that the diquat dichloride salt particles can fall into the barrel 42 through the opening 41, and the reversely inclined scrapers 43 can push the diquat dichloride salt particles on both sides of the annular material channel to the middle, thereby achieving a comprehensive discharge effect.

[0038] The rotating spiral plate 3 will cause turbulence, which reduces the filtering effect to a certain extent. It is necessary to adjust the speed of the spiral plate 3 according to the blockage condition of the filter cartridge 2 to further reduce the influence of the spiral plate 3 on the filtering efficiency. The specific operation is as follows:

[0039] like Figure 2 , Figure 7As shown, the driving assembly includes a motor 7 and a transmission wheel assembly, a protective shell is fixed on the top of the ring box 4, the motor 7 is installed on the top of the protective shell, the rotating sleeve 9 penetrates into the protective shell, the top opening of the rotating sleeve 9 has an inclined rough surface 91, the transmission wheel includes an active conical wheel 71, a driven conical wheel 72 and a roller 6, a plunger body 5 is vertically slid above the inside of the filter cartridge 2, a spring is arranged below the plunger body 5, and is used to apply an upward elastic force to the plunger body 5, a shaft rod 51 is fixed on the upper surface of the plunger body 5, the shaft rod 51 penetrates upward from the filter cartridge 2 to the protective shell, and the roller 6 is rotatably installed on the top of the shaft rod 51, the active conical wheel 71 and the driven conical wheel 72 are arranged on the roller The driving conical wheel 71 and the driven conical wheel 72 have the same size specifications, and the generatrix of the driving conical wheel 71, the driven conical wheel 72 and the roller 6 are all vertical lines, ensuring that the roller 6 can evenly squeeze and contact the driving conical wheel 71 and the driven conical wheel 72 when moving vertically. The small diameter end of the driving conical wheel 71 is upward, and the small diameter end of the driven conical wheel 72 is downward. The surfaces of the driving conical wheel 71 and the driven conical wheel 72 have rough textures to increase the friction force of contact with the roller 6. The driven conical wheel 72 is squeezed and frictionally contacted with the rough surface 91, and the output shaft of the motor 7 is connected to the driving conical wheel 71;

[0040] The motor 7 drives the active conical wheel 71 to rotate, and the active conical wheel 71 drives the driven conical wheel 72 to rotate through the roller 6. The driven conical wheel 72 drives the rotating sleeve 9 to rotate by friction, so that the spiral plate 3 rotates to scrape the outer wall of the filter cartridge 2 and conduct the diquat dichloride salt particles upward. When the permeability of the filter cartridge 2 is high, the negative pressure in the filter cartridge 2 is low, and the spring pushes the plunger body 5 to a higher position, so that the roller 6 is located at the upper part of the active conical wheel 71 and the driven conical wheel 72. At this time, the roller 6 contacts the small diameter part of the active conical wheel 71 and the large diameter part of the driven conical wheel 72, so that the spiral plate 3 The rotation speed is slow, which reduces the turbulence of the spiral plate 3 and ensures efficient filtration of the filter cartridge 2. As the diquat dichloride salt particles block the outer surface of the filter cartridge 2, the permeability of the filter cartridge 2 gradually decreases, and the negative pressure inside the filter cartridge 2 gradually increases. The plunger body 5 gradually descends under the negative pressure, causing the height of the roller 6 to gradually decrease. The diameter of the roller 6 contacting the active conical wheel 71 gradually increases, and the diameter of the roller 6 contacting the driven conical wheel 72 gradually decreases, so that the rotation speed of the spiral plate 3 gradually increases, and the efficiency of the spiral plate 3 in scraping and conducting the diquat dichloride salt particles is improved, ensuring that the filter cartridge 2 maintains good permeability.

[0041] like Figure 2As shown, a carrier plate 52 is slidably arranged at the lower part of the filter cartridge 2, and a spring for elastically squeezing the plunger body 5 upward is arranged between the plunger body 5 and the carrier plate 52. A stud 53 is passed through the bottom thread of the filter cartridge 2, and the stud 53 presses upward against the carrier plate 52 to position the height of the carrier plate 52. The height of the carrier plate 52 is adjusted by rotating the stud 53, so that the upward elastic force applied by the spring to the plunger body 5 changes, which is used to adjust the sensitivity of the rotation speed of the spiral plate 3 to the change of negative pressure.

[0042] like Figure 6 As shown, the roller 6 includes a core barrel 61, which is rotatably arranged on the outside of the shaft 51 through a bearing, a bottom plate 62 is fixed to the bottom of the core barrel 61, a top plate 63 is sleeved on the top of the core barrel 61, and a rubber tube 65 is connected between the top plate 63 and the bottom plate 62. The two ends of the rubber tube 65 can be directly fixed to the top plate 63 and the bottom plate 62, or the rubber tube 65 can be limited in a sleeve manner so that the rubber tube 65 is coaxially aligned with the top plate 63 and the bottom plate 62. A nut 64 is threadedly connected to the outside of the core barrel 61, and the nut 64 presses down the top plate 63. The spacing between the top plate 63 and the bottom plate 62 is changed by rotating the nut 64, which is used to adjust the amplitude of squeezing the rubber tube 65 by the top plate 63 and the bottom plate 62, so that the expansion diameter of the rubber tube 65 changes. When the roller 6 works for a long time and the diameter becomes smaller due to wear, the diameter of the roller 6 can be compensated by compressing the rubber tube 65, so that the roller 6 can stably transmit the driven conical wheel 72.

[0043] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Equipment for preparing, crystallizing and separating diquat dichloride salt, including: An outer cylinder (1), wherein a filter cylinder (2) is coaxially fixed to the inner cylinder of the outer cylinder (1), a separation gap is formed between the outer cylinder (1) and the filter cylinder (2), the outer cylinder (1) is connected to a feed port (11), the feed port (11) is used to conduct materials into the separation gap, and the filter cylinder (2) is characterized in that a discharge port (21) is provided at the bottom, the discharge port (21) is connected to a negative pressure pump (8), and the negative pressure pump (8) sucks the discharge port (21) to generate negative pressure in the filter cylinder (2), thereby separating liquid materials in the separation gap. After penetrating the filter cartridge (2), the particles are discharged from the discharge port (21), so that the particles are retained in the separation gap. A spiral plate (3) is provided in the separation gap. The inner and outer edges of the spiral plate (3) are respectively in sliding contact with the filter cartridge (2) and the outer cylinder (1). The top of the spiral plate (3) is connected to a driving component. The top of the outer cylinder (1) is provided with a material receiving component. The spiral plate (3) is driven to rotate by the driving component, so that the spiral plate (3) scrapes the particles on the surface of the filter cartridge (2) and conducts them upward to the material receiving component. The driving assembly comprises a motor (7), a rotating sleeve (9) is rotatably provided on the top periphery of the filter cartridge (2), an output shaft of the motor (7) is drivingly connected to the rotating sleeve (9) via a transmission wheel assembly, and the spiral plate (3) is fixedly connected to the rotating sleeve (9); The transmission wheel comprises an active conical wheel (71), a driven conical wheel (72) and a roller (6); a plunger body (5) is vertically slidably disposed above the interior of the filter cartridge (2); a spring is connected to the plunger body (5) for applying an upward elastic force to the plunger body (5); a shaft (51) is fixed to the plunger body (5); the shaft (51) passes through the filter cartridge (2) upward; the roller (6) is rotatably mounted on the top of the shaft (51); the active conical wheel (71) and the driven conical wheel (72) are The rotating sleeve (9) is located on both sides of the roller (6) and is in pressure contact with the roller (6), and the generatrix of the driving conical wheel (71) and the driven conical wheel (72) in contact with the roller (6) are both vertical lines, the top of the rotating sleeve (9) has a rough surface (91), the driven conical wheel (72) is in pressure contact with the rough surface (91), the output shaft of the motor (7) is connected to the driving conical wheel (71), the small diameter end of the driving conical wheel (71) is upward, and the small diameter end of the driven conical wheel (72) is downward.

2. The preparation, crystallization and separation equipment of diquat dichloride according to claim 1, characterized in that: The roller (6) comprises a core barrel (61), which is rotatably arranged on the outside of the shaft (51) via a bearing, a bottom plate (62) is fixed to the bottom of the core barrel (61), a top plate (63) is sleeved on the top of the core barrel (61), a rubber barrel (65) is connected between the top plate (63) and the bottom plate (62), and a nut (64) is threadedly connected to the outside of the core barrel (61), and the nut (64) is used to press down the top plate (63), so that the top plate (63) and the bottom plate (62) squeeze the rubber barrel (65) to deform and expand outwards.

3. The preparation, crystallization and separation equipment of diquat dichloride according to claim 1, characterized in that: A carrier plate (52) is slidably disposed at the lower portion of the filter cartridge (2); a spring for elastically pressing the plunger body (5) upward is disposed between the plunger body (5) and the carrier plate (52); a stud (53) is threaded through the bottom of the filter cartridge (2); the stud (53) abuts against the carrier plate (52) upward, and is used to position the height of the carrier plate (52).

4. The preparation, crystallization and separation equipment of diquat dichloride according to claim 1, characterized in that: The material receiving assembly comprises a ring box (4), the ring box (4) being fixed to the periphery of the top opening of the outer cylinder (1), a plurality of through openings (41) being provided on the bottom surface of the ring box (4), and a material cylinder (42) being connected below the through openings (41).

5. The preparation, crystallization and separation equipment of diquat dichloride according to claim 4, characterized in that: A plurality of scrapers (43) are fixed around the rotating sleeve (9), the scrapers (43) being used to scrape the inner bottom surface of the ring box (4), the scrapers (43) being arranged obliquely with respect to the radial line of the ring box (4), and the inclination directions of adjacent scrapers (43) being opposite.

6. The preparation, crystallization and separation equipment of diquat dichloride according to claim 4, characterized in that: The barrel (42) is threadedly connected to the through port (41).

7. The preparation, crystallization and separation equipment of diquat dichloride according to claim 1, characterized in that: The cross section of the spiral plate (3) is inclined downward at one end close to the outer cylinder (1).

8. A method for separating diquat dichloride salt based on the diquat dichloride salt preparation crystallization separation device according to any one of claims 1 to 7, characterized in that: The specific steps are as follows: A. A solvent containing diquat dichloride salt particles is continuously introduced into the separation gap through the feed port (11), and the negative pressure pump (8) is turned on to suck the discharge port (21), so that negative pressure is generated inside the filter cartridge (2). The solvent passes through the filter cartridge (2) and is discharged from the discharge port (21), and the diquat dichloride salt particles are retained in the separation gap; B. The spiral plate (3) is driven to rotate by the driving assembly. The spiral plate (3) scrapes off the diquat dichloride salt particles adsorbed on the outside of the filter cartridge (2) and conducts them upward, so that the diquat dichloride salt particles fall into the receiving assembly and are collected, thereby preventing the diquat dichloride salt particles from clogging the filter cartridge (2).

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