Polyacrylonitrile slurry demonomerisation device and demonomerisation method

Abstract

The invention belongs to the field of high-molecular polymer equipment, and particularly relates to a polyacrylonitrile slurry demonomerisation device and a demonomerisation method. Comprising an acetonitrile separation unit, a transpiration PAN capture unit and a slurry discharge unit, the acetonitrile separation unit comprises a main body tank and multiple groups of first tower plates, the multiple groups of first tower plates are arranged in the main body tank in a staggered manner, and the main body tank is provided with a slurry inlet pipeline, a steam inlet pipeline, a vacuumizing pipeline and a temperature control jacket; through combined arrangement of the inclined baffle and the horizontal segmental plate with the exhaust holes, fluid area spreading of slurry is achieved, and meanwhile separation of residual AN monomers in the slurry is achieved through combination of reverse steam introduction and slurry fluid spreading. A plurality of groups of staggered tower plates with segment structures are arranged in the upper auxiliary tank and are matched with a water mist spraying device, so that a small amount of transpiration PAN in slurry is captured and dissolved, and the demonomerisation device can be conveniently disassembled, assembled and maintained.

Description

Technical Field

[0001] The invention belongs to the field of high molecular polymer equipment, and in particular relates to a polyacrylonitrile slurry single-removal device and a single-removal method. Background Art

[0002] As the main type of high-strength carbon fiber, polyacrylonitrile (PAN)-based carbon fiber has developed into the most widely used type of carbon fiber with the largest output in recent years. High-quality carbon fiber precursor is an important prerequisite for the preparation of high-performance PAN-based carbon fiber. However, there will be acetonitrile (AN) monomer residue in the PAN after polymerization. If the residual amount of AN monomer in the polyacrylonitrile polymerization solution is large, the residual monomer AN will further undergo polymerization reaction during the subsequent degassing process, resulting in unstable solid content of the spinning solution of the precursor, resulting in a large discrete problem of the quality of the precursor. Therefore, in the preparation process of PAN precursor, the removal of AN monomer is a key process that determines the quality of the final PAN-based carbon fiber.

[0003] In the prior art, the de-monomerization treatment of PAN spinning stock solution mostly adopts de-monomerization kettle or de-monomerization tower equipment. However, on the one hand, the de-monomerization kettle has a complex structure, which is generally an integrated structure or a combined structure, and the control equipment for the extension or rheological properties of the stock solution inside the tower kettle is mostly an integrated structure, which is difficult to maintain or clean. On the other hand, when de-monomerization is carried out under the conditions provided by the existing equipment, PAN is easily volatilized with the AN monomer, resulting in unstable solid content. Summary of the invention

[0004] In view of the above problems existing in the prior art, the present invention provides a polyacrylonitrile slurry single-drying device and a single-drying method, which can avoid the volatilization of polyacrylonitrile and efficiently remove the single-drying agent.

[0005] To achieve the above object, the technical solution provided by the present invention is as follows:

[0006] In the first aspect, the present application provides a polyacrylonitrile slurry monomer removal device, comprising an acetonitrile separation unit, a transpiration PAN capture unit and a slurry discharge unit, the acetonitrile separation unit comprising a main tank and a first tower plate, a plurality of groups of first tower plates are arranged in a staggered manner in the main tank, a slurry inlet pipeline, a steam inlet pipeline, a vacuum pipeline and a temperature control jacket are provided on the main tank, the temperature control jacket is coated on the outer periphery of the main tank, the vacuum pipeline is used to control the pressure in the main tank, and the slurry inlet pipeline is arranged above the steam inlet pipeline; the transpiration PAN capture unit comprises an upper auxiliary tank and a spray device, the upper auxiliary tank is connected above the main tank, a spray device is provided in the upper auxiliary tank, and a monomer mixed steam outlet pipeline is provided on the top of the upper auxiliary tank; the slurry discharge unit comprises a lower auxiliary tank, the lower auxiliary tank is connected below the main tank, and a slurry outlet pipeline is provided on the lower auxiliary tank.

[0007] Optionally, the first tower plate comprises a horizontal circular notch plate, the arc edge of the horizontal circular notch plate is in contact with the inner wall of the main tank body, and the angle of the circular notch part of the horizontal circular notch plate is 90°-170°.

[0008] Optionally, the horizontal circular plate is detachably provided with an inclined baffle, the angle between the inclined baffle and the horizontal circular plate is 10°-60°, the horizontal circular plate is provided with an exhaust hole, the exhaust port on the horizontal circular plate is within the vertical projection range of the inclined baffle, and the line connecting the inclined baffle and the horizontal circular plate is parallel to the chord corresponding to the two end points of the arc on the horizontal circular plate.

[0009] Optionally, the horizontal circular plate is provided with a small baffle above each exhaust hole, and the vertical projection area of ​​the small baffle coincides with the area of ​​the corresponding exhaust hole.

[0010] Optionally, a circulating water pipeline is arranged in the temperature control jacket, and the circulating water pipeline is arranged in a spiral or reciprocating serpentine coil. The inlet of the circulating water pipeline is arranged at the bottom of the jacket, and the outlet of the circulating water pipeline is arranged at the top of the jacket on the side opposite to the inlet.

[0011] Optionally, the upper auxiliary tank is connected to a spray device via a water mist inlet pipeline, and the spray device sprays toward the monomer mixed steam outlet pipeline.

[0012] Optionally, second tower plates are arranged in an alternating manner in the upper auxiliary tank, and a plurality of the second tower plates are arranged between the spray device and the main tank.

[0013] Optionally, a temperature-control jacket is provided on the outer periphery of the lower auxiliary tank, and a vacuum pump is provided on the slurry outlet pipeline.

[0014] Optionally, the upper auxiliary tank, the lower auxiliary tank and the main tank body are connected by flanges, and a detachable slot-type connection is adopted between the first tower plate and the main tank body.

[0015] In a second aspect, the present application also provides a method for escaping from being single using the above-mentioned device.

[0016] Compared with the prior art, this application has at least the following beneficial effects:

[0017] 1. The main tank body adopts multiple groups of staggered tower plates with circular structures. The fluid area spreading of the slurry is realized through the joint setting of inclined baffles and horizontal circular plates with exhaust holes. At the same time, the reverse steam is introduced and combined with the slurry fluid spreading to realize the separation of residual AN monomer in the slurry.

[0018] Second, multiple groups of staggered tower plates with circular structures are arranged in the upper auxiliary tank, and a water mist spray device is used at the same time. The spraying direction is consistent with the steam flow direction, which promotes the evaporation of AN monomer and ensures sufficient contact and absorption between the sprayed water mist and the evaporated residual PAN, so as to capture and dissolve a small amount of evaporated PAN in the sludge and achieve secondary fine separation of the escaped AN monomer in the main phase separation treatment of the middle section, so as to fully ensure the separation of residual PAN in the sludge and the liquid-gas phase separation and removal of AN monomer.

[0019] 3. The main tank body, the upper auxiliary tank and the lower auxiliary tank are connected by flange combination, and the tower plates in the main tank and the upper auxiliary tank are connected by detachable slot type, and the horizontal circular plate and the inclined baffle plate also adopt a detachable structure, which realizes the convenient disassembly and maintenance of the single removal device, and can realize the flexible combination setting of the phase separation process of AN monomer, and the equipment is easy to produce. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is a schematic structural diagram of a polyacrylonitrile slurry single-drying device in an embodiment of the present application;

[0022] Figure 2 This is a schematic diagram of the structure of the first tray in the embodiment of the present application;

[0023] Description of reference numerals:

[0024] 1. Acetonitrile separation unit; 11. Main tank; 12. First tower plate; 121. Horizontal circular plate; 122. Oblique baffle; 123. Exhaust hole; 124. Small baffle; 13. Slurry inlet pipeline; 14. Steam inlet pipeline; 15. Vacuum pipeline; 16. Temperature control jacket; 17. Circulating water pipeline; 171. Circulating water inlet; 172. Circulating water outlet; 2. Evaporative PAN capture unit; 21. Upper auxiliary tank; 22. Spraying device; 23. Second tower plate; 24. Monomer mixed steam outlet pipeline; 3. Slurry discharge unit; 31. Lower auxiliary tank; 32. Temperature control jacket; 33. Slurry outlet pipeline; 4. Flange. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its application or use.

[0026] Example 1

[0027] like Figure 1 As shown, a polyacrylonitrile slurry monomer removal device includes an acetonitrile separation unit 1, a transpiration PAN capture unit 2 and a slurry discharge unit 3, wherein the acetonitrile separation unit 1 is the main structure for phase separation of AN monomers, ensuring the liquid-gas two-phase separation of AN monomers in the slurry in the entire device; the transpiration PAN capture unit 2 and the slurry discharge unit 3 above are for cooperating with the middle section AN monomer removal separation process, realizing the capture and dissolution of a small amount of transpiration PAN in the slurry and the secondary fine separation of the escaped AN monomer in the treatment of the acetonitrile separation unit 1; the slurry discharge unit 3 below is a heating and storage structure, realizing the heating, storage and recovery functions of the slurry after phase separation treatment.

[0028] The acetonitrile separation unit 1 comprises a main tank 11 and a first tray 12. A plurality of first trays 12 are arranged in a staggered manner in the main tank 11. In the present embodiment, 10 to 50 first trays 12 are evenly and staggeredly arranged in the main tank body. In the present embodiment, there are 30 first trays 12. A slurry inlet pipeline 13, a steam inlet pipeline 14, a vacuum pipeline 15 and a temperature control jacket 16 are provided on the main tank 11. The temperature control jacket 16 is coated on the outer periphery of the main tank 11. The vacuum pipeline 15 is located in the middle of the side wall of the main tank body to control the vacuum degree. The slurry inlet pipeline 13 is arranged above the plurality of first trays 12. The steam inlet pipeline 14 is arranged below the multiple groups of first tower plates 12; a circulating water pipeline 17 is arranged in the temperature control jacket 16, and the distance between the circulating water pipeline 17 and the inner wall of the main tank body is 1 / 20-1 / 10 of the radius of the main tank body. The inner radius of the main tank body is 20 cm, and the diameter of the circulating water pipeline 17 in the jacket is 3 cm. The circulating water pipeline 17 is arranged in a spiral manner, and the internal pipeline spacing of the circulating water pipeline 17 is 3 mm. The distance between the circulating water pipeline 17 and the inner wall of the main pipe is 2 cm. The circulating water pipeline inlet 171 is arranged at the bottom of the jacket, and the circulating water pipeline outlet 172 is arranged on the top side wall of the jacket opposite to the inlet.

[0029] The first tower plate 12 includes a horizontal circular plate 121, the arc edge of the horizontal circular plate 121 is in contact with the inner wall of the main tank, and the angle of the circular portion of the horizontal circular plate 121 is 90°; an inclined baffle 122 is provided on the horizontal circular plate 121, and the inclined baffle 122 is obliquely inserted on the horizontal circular plate 121. The angle between the inclined baffle 122 and the horizontal circular plate 121 is controlled within the range of 10°-60°, and is 30° in this embodiment. The connecting line between the inclined baffle 122 and the horizontal circular plate 121 is on the perpendicular midline of the radius of the horizontal circular plate 121, and is aligned with the two end points of the arc on the horizontal circular plate 121. The chord should be parallel, and a plurality of exhaust holes 123 are provided on the inclined baffle plate 122 and the horizontal circular plate 121. The opening diameter of the exhaust hole 123 is controlled within the range of 0.5-5 cm. In this embodiment, the diameter of the exhaust hole 123 is 2 cm. The exhaust hole 123 on the horizontal circular plate 121 falls within the vertical projection range of the inclined baffle plate 122. The horizontal circular plate 121 is provided with a small baffle 124 above the exhaust hole 123. The opening angle of the small baffle 124 is controlled within the range of 10°-60°, which is 20° in this embodiment. The vertical projection area of ​​the small baffle 124 coincides with the area of ​​the exhaust hole 123.

[0030] The transpiration PAN capture unit 2 includes an upper auxiliary tank 21 and a spray device 22. The upper auxiliary tank 21 is connected above the main tank 11. The upper auxiliary tank 21 is hemispherical. A monomer mixed steam outlet pipeline 24 is arranged on the top of the upper auxiliary tank 21. A disc-type spray device 22 with a water mist spray direction toward the top of the tank body is arranged in the upper auxiliary tank 21; the second tower plates 23 are staggeredly arranged below the spray device 22 in the upper auxiliary tank 21. The second tower plates 23 adopt the same structure as the first tower plates 12. The second tower plates 23 can be arranged in 2-5 groups. In this embodiment, there are 5 groups of second tower plates 23.

[0031] The slurry discharge unit 3 includes a lower auxiliary tank 31, which is connected to the bottom of the main tank 11. A temperature control jacket 32 ​​is provided on the outside of the lower auxiliary tank 31 to control the water temperature in the temperature control jacket 16 of the lower auxiliary tank 31 within the range of 25-60°C, 50°C in this embodiment, to maintain the appropriate viscosity and fluidity of the PAN-removed slurry, to avoid the effect of too low temperature on the fluidity of the slurry or too high temperature on the excessive evaporation of PAN, and the design structure and size of the temperature control jacket 32 ​​are consistent with the design of the temperature control jacket 16 of the main tank 11. The lower auxiliary tank 31 is hemispherical, and a slurry outlet pipeline 33 is provided at the bottom of the lower auxiliary tank 31. A vacuum pump is provided on the slurry outlet pipeline, and the extraction, recovery and storage of the AN-removed slurry after phase separation treatment are realized by driving the vacuum pump.

[0032] The upper auxiliary tank 21, the lower auxiliary tank 31 and the main tank body are connected by flange 4, and the first tower plate 12 and the main tank body are connected by a detachable slot type connection, which realizes the convenient disassembly and maintenance of the single removal device, and the phase separation process of the AN monomer can be flexibly combined and set, and the equipment is easy to produce.

[0033] The method of removing the single using the above device is as follows:

[0034] First, the circulating water pipeline 17 of the main tank body is opened. The temperature of the circulating water pipeline 17 is 25-60°C. In this embodiment, the water temperature in the circulating water pipeline 17 is 25°C. The main tank body is preheated by using the temperature control jacket 16. At the same time, the vacuum pipeline 15 of the main tank body is opened to keep the vacuum degree in the main tank body in the range of -0.05 to -0.1MPa. In this embodiment, the internal vacuum degree is controlled to -0.1MPa.

[0035] Then, the slurry inlet pipeline 13 is opened, and the steam inlet pipeline 14 is opened at the same time, and the slurry is sent into the pipe from the top of the main tank body. The slurry is transmitted through the staggered serpentine channels of the staggered horizontal circular plates 121, and the flow area of ​​the slurry is spread through the non-porous inclined baffles 122 arranged on the horizontal circular plates 121 and the circular small baffles 124 of the exhaust holes 123; the steam is introduced in the reverse direction from the exhaust holes 123 and fully contacts with the flowing and spreading slurry material, so that the AN monomer in the slurry is fully dissolved to achieve liquid-gas two-phase separation treatment, and the AN monomer in the slurry is dissolved in the steam and then extracted through the monomer mixed steam outlet pipeline 24 at the top for subsequent water and AN monomer two-phase separation;

[0036] The undissolved PAN residue in the slurry will evaporate. By opening the disc-type water mist spray device 22 on the top, the residual PAN in the slurry will be further dissolved under the action of water mist, flowing from the top of the tank body and settling and mixing into the slurry. At the same time, combined with the second tower plate 23 in the upper auxiliary tank 21, the evaporating residual PAN can be further captured, dissolved and refluxed.

[0037] Finally, the AN monomer mixed steam outlet pipeline 24 is extracted and collected at the top of the upper auxiliary tank 21, and the slurry raw material after AN monomer removal treatment is extracted and stored at the bottom of the lower auxiliary tank 31 to achieve liquid-gas two-phase separation treatment of AN monomer in the slurry.

[0038] Example 2

[0039] like Figure 1 As shown, a polyacrylonitrile slurry monomer removal device includes an acetonitrile separation unit 1, a transpiration PAN capture unit 2 and a slurry discharge unit 3, wherein the acetonitrile separation unit 1 is the main structure for phase separation of AN monomers, ensuring the liquid-gas two-phase separation of AN monomers in the slurry in the entire device; the transpiration PAN capture unit 2 and the slurry discharge unit 3 above are for cooperating with the middle section AN monomer removal separation process, realizing the capture and dissolution of a small amount of transpiration PAN in the slurry and the secondary fine separation of the escaped AN monomer in the treatment of the acetonitrile separation unit 1; the slurry discharge unit 3 below is a heating and storage structure, realizing the heating, storage and recovery functions of the slurry after phase separation treatment.

[0040] The acetonitrile separation unit 1 comprises a main tank 11 and a first tray 12, wherein a plurality of first trays 12 are arranged in a staggered manner in the main tank 11. In the present embodiment, 10 to 50 first trays 12 are evenly and staggeredly arranged in the main tank body. In the present embodiment, there are 20 first trays 12. A slurry inlet pipeline 13, a steam inlet pipeline 14, a vacuum pipeline 15 and a temperature control jacket 16 are arranged on the main tank 11. The temperature control jacket 16 is coated on the outer periphery of the main tank 11. The vacuum pipeline 15 is located in the middle of the side wall of the main tank body to control the vacuum degree. The slurry inlet pipeline 13 is arranged on the plurality of first trays 12. The steam inlet pipeline 14 is arranged below the multiple groups of first tower plates 12; a circulating water pipeline 17 is arranged in the temperature control jacket 16, and the distance between the circulating water pipeline 17 and the inner wall of the main tank body is 1 / 20-1 / 10 of the radius of the main tank body. The inner radius of the main tank body is 30 cm, and the diameter of the circulating water pipeline 17 in the jacket is 4 cm. The circulating water pipeline 17 is arranged in a spiral manner, and the internal pipeline spacing of the circulating water pipeline 17 is 4 mm. The distance between the circulating water pipeline 17 and the inner wall of the main body is 3 cm. The inlet of the circulating water pipeline is arranged at the bottom of the jacket, and the outlet of the circulating water pipeline is arranged on the top side wall of the jacket opposite to the inlet.

[0041] The first tower plate 12 includes a horizontal circular plate 121, the arc edge of the horizontal circular plate 121 is in contact with the inner wall of the main tank body, and the angle of the circular part of the horizontal circular plate 121 is 100°; the horizontal circular plate 121 is provided with an inclined baffle 122, which is obliquely inserted on the horizontal circular plate 121, and the angle between the inclined baffle 122 and the horizontal circular plate 121 is controlled in the range of 10°-60°, which is 35° in the present embodiment, and the connecting line between the inclined baffle 122 and the horizontal circular plate 121 is a perpendicular line to the midpoint of the radius of the entire semicircular surface of the horizontal circular plate 121, and its direction is parallel to the circular line of the horizontal circular plate 121. A plurality of exhaust holes 123 are provided on the horizontal circular plate 121, and the opening diameter of the exhaust holes 123 is controlled within the range of 0.5-5 cm. In the present embodiment, the diameter of the exhaust holes 123 is 1 cm. The exhaust holes 123 on the horizontal circular plate 121 fall within the vertical projection range of the inclined baffle 122. A small baffle 124 is provided above the exhaust holes 123 on the horizontal circular plate 121, and the opening angle of the small baffle 124 is controlled within the range of 10°-60°, which is 20° in the present embodiment. The vertical projection area of ​​the small baffle 124 coincides with the area of ​​the exhaust holes 123.

[0042] The transpiration PAN capture unit 2 includes an upper auxiliary tank 21 and a spray device 22. The upper auxiliary tank 21 is connected above the main tank 11. The upper auxiliary tank 21 is hemispherical. A monomer mixed steam outlet pipeline 24 is arranged on the top of the upper auxiliary tank 21. A disc-type spray device 22 with a water mist spray direction toward the top of the tank body is arranged in the upper auxiliary tank 21; the second tower plates 23 are staggeredly arranged below the spray device 22 in the upper auxiliary tank 21. The second tower plates 23 adopt the same structure as the first tower plates 12. The second tower plates 23 can be arranged in 2-5 groups. In this embodiment, there are 4 groups of second tower plates 23.

[0043] The slurry discharge unit 3 includes a lower auxiliary tank 31, which is connected to the bottom of the main tank 11. A temperature control jacket 32 ​​is provided on the outside of the lower auxiliary tank 31 to control the water temperature in the temperature control jacket 16 of the lower auxiliary tank 31 within the range of 25-60°C. In this embodiment, the temperature is not 45°C to maintain the proper viscosity and fluidity of the de-monomer slurry. The design structure and size of the temperature control jacket 32 ​​are consistent with the design of the temperature control jacket 16 of the main tank 11. The lower auxiliary tank 31 is hemispherical, and a slurry outlet pipeline 33 is provided at the bottom of the lower auxiliary tank 31. A vacuum pump is provided on the slurry outlet pipeline, and the extraction, recovery and storage of the AN de-monomer slurry after phase separation treatment are realized by driving the vacuum pump.

[0044] The upper auxiliary tank 21, the lower auxiliary tank 31 and the main tank body are connected by flange 4, and the first tower plate 12 and the main tank body are connected by a detachable slot type connection, which realizes the convenient disassembly and maintenance of the single removal device, and the phase separation process of the AN monomer can be flexibly combined and set, and the equipment is easy to produce.

[0045] The method of removing the single using the above device is as follows:

[0046] First, the circulating water pipeline 17 of the main tank body is opened. The temperature of the circulating water pipeline 17 is 25-60°C. In this embodiment, the water temperature in the circulating water pipeline 17 is 35°C. The main tank body is preheated by using the temperature control jacket 16. At the same time, the vacuum pipeline 15 of the main tank body is opened to keep the vacuum degree in the main tank body in the range of -0.05 to -0.1MPa. In this embodiment, the internal vacuum degree is controlled to -0.08MPa.

[0047] Then, the slurry inlet pipeline 13 is opened, and the steam inlet pipeline 14 is opened at the same time, and the slurry is sent into the pipe from the top of the main tank body. The slurry is transmitted through the staggered serpentine channels of the staggered horizontal circular plates 121, and the flow area of ​​the slurry is spread through the non-porous inclined baffles 122 arranged on the horizontal circular plates 121 and the circular small baffles 124 of the exhaust holes 123; the steam is introduced in the reverse direction from the exhaust holes 123 and fully contacts with the flowing and spreading slurry material, so that the AN monomer in the slurry is fully dissolved to achieve liquid-gas two-phase separation treatment, and the AN monomer in the slurry is dissolved in the steam and then extracted through the monomer mixed steam outlet pipeline 24 at the top for subsequent water and AN monomer two-phase separation;

[0048] The undissolved PAN residue in the slurry will evaporate. By opening the disc-type water mist spray device 22 on the top, the residual PAN in the slurry will be further dissolved under the action of water mist, flowing from the top of the tank body and settling and mixing into the slurry. At the same time, combined with the second tower plate 23 in the upper auxiliary tank 21, the evaporating residual PAN can be further captured, dissolved and refluxed.

[0049] Finally, the AN monomer mixed steam outlet pipeline 24 is extracted and collected at the top of the upper auxiliary tank 21, and the slurry raw material after AN monomer removal treatment is extracted and stored at the bottom of the lower auxiliary tank 31 to achieve liquid-gas two-phase separation treatment of AN monomer in the slurry.

[0050] Example 3

[0051] like Figure 1 As shown, a polyacrylonitrile slurry monomer removal device includes an acetonitrile separation unit 1, a transpiration PAN capture unit 2 and a slurry discharge unit 3, wherein the acetonitrile separation unit 1 is the main structure for phase separation of AN monomers, ensuring the liquid-gas two-phase separation of AN monomers in the slurry in the entire device; the transpiration PAN capture unit 2 and the slurry discharge unit 3 above are for cooperating with the middle section AN monomer removal separation process, realizing the capture and dissolution of a small amount of transpiration PAN in the slurry and the secondary fine separation of the escaped AN monomer in the treatment of the acetonitrile separation unit 1; the slurry discharge unit 3 below is a heating and storage structure, realizing the heating, storage and recovery functions of the slurry after phase separation treatment.

[0052] The acetonitrile separation unit 1 comprises a main tank 11 and a first tray 12, wherein a plurality of first trays 12 are arranged in a staggered manner in the main tank 11. In the present embodiment, 10 to 50 first trays 12 are evenly and staggeredly arranged in the main tank body. In the present embodiment, there are 45 first trays 12. A slurry inlet pipeline 13, a steam inlet pipeline 14, a vacuum pipeline 15 and a temperature control jacket 16 are arranged on the main tank 11. The temperature control jacket 16 is coated on the outer periphery of the main tank 11. The vacuum pipeline 15 is located in the middle of the side wall of the main tank body to control the vacuum degree. The slurry inlet pipeline 13 is arranged above the plurality of first trays 12, and the steam inlet pipeline 14 is arranged above the plurality of first trays 12. The inlet pipeline 14 is arranged below the multiple groups of first tower plates 12; a circulating water pipeline 17 is arranged in the temperature control jacket 16, and the distance between the circulating water pipeline 17 and the inner wall of the main tank body is 1 / 20-1 / 10 of the radius of the main tank body. The inner radius of the main tank body is 50 cm, and the diameter of the circulating water pipeline 17 in the jacket is 2.5 cm. The circulating water pipeline 17 is a reciprocating serpentine coil water channel structure, and the internal pipeline spacing of the circulating water pipeline 17 is 2.5 mm. The distance between the circulating water pipeline 17 and the inner wall of the main body is 5 cm. The inlet of the circulating water channel is arranged at the bottom of the jacket, and the outlet of the circulating water channel is arranged on the top side wall of the jacket facing away from the inlet.

[0053] The first tower plate 12 includes a horizontal circular plate 121, the arc edge of the horizontal circular plate 121 is in contact with the inner wall of the main tank body, and the angle of the circular part of the horizontal circular plate 121 is 120°; an inclined baffle 122 is provided on the horizontal circular plate 121, and the inclined baffle 122 is obliquely inserted on the horizontal circular plate 121, and the angle between the inclined baffle 122 and the horizontal circular plate 121 is controlled in the range of 10°-60°, and is 55° in the present embodiment. The connecting line between the inclined baffle 122 and the horizontal circular plate 121 is a perpendicular line to the midpoint of the radius of the entire semicircular surface of the horizontal circular plate 121, and its direction is parallel to the circular line of the horizontal circular plate 121. A plurality of exhaust holes 123 are provided on the horizontal circular plate 121, and the opening diameter of the exhaust holes 123 is controlled within the range of 0.5-5 cm. In the present embodiment, the diameter of the exhaust holes 123 is 4 cm. The exhaust holes 123 on the horizontal circular plate 121 fall within the vertical projection range of the inclined baffle 122. A small baffle 124 is provided above the exhaust holes 123 on the horizontal circular plate 121, and the opening angle of the small baffle 124 is controlled within the range of 10°-60°, which is 35° in the present embodiment. The vertical projection area of ​​the small baffle 124 coincides with the area of ​​the exhaust holes 123.

[0054] The transpiration PAN capture unit 2 includes an upper auxiliary tank 21 and a spray device 22. The upper auxiliary tank 21 is connected above the main tank 11. The upper auxiliary tank 21 is hemispherical. A monomer mixed steam outlet pipeline 24 is arranged on the top of the upper auxiliary tank 21. A disc-type spray device 22 with a water mist spray direction toward the top of the tank body is arranged in the upper auxiliary tank 21; the second tower plates 23 are staggeredly arranged below the spray device 22 in the upper auxiliary tank 21. The second tower plates 23 adopt the same structure as the first tower plates 12. The second tower plates 23 can be arranged in 2-5 groups. In this embodiment, there are 3 groups of second tower plates 23.

[0055] The slurry discharge unit 3 includes a lower auxiliary tank 31, which is connected to the bottom of the main tank 11. A temperature control jacket 32 ​​is provided on the outside of the lower auxiliary tank 31 to control the water temperature in the temperature control jacket 16 of the lower auxiliary tank 31 within the range of 25-60°C. In this embodiment, the temperature is 40°C to maintain the proper viscosity and fluidity of the de-monomer slurry. The design structure and size of the temperature control jacket 32 ​​are consistent with the design of the temperature control jacket 16 of the main tank 11. The lower auxiliary tank 31 is hemispherical, and a slurry outlet pipeline 33 is provided at the bottom of the lower auxiliary tank 31. A vacuum pump is provided on the slurry outlet pipeline, and the extraction, recovery and storage of the AN de-monomer slurry after phase separation treatment are realized by driving the vacuum pump.

[0056] The upper auxiliary tank 21, the lower auxiliary tank 31 and the main tank body are connected by flange 4, and the first tower plate 12 and the main tank body are connected by a detachable slot type connection, which realizes the convenient disassembly and maintenance of the single removal device, and the phase separation process of the AN monomer can be flexibly combined and set, and the equipment is easy to produce.

[0057] The method of removing the single using the above device is as follows:

[0058] First, the circulating water pipeline 17 of the main tank body is opened. The temperature of the circulating water pipeline 17 is 25-60°C. In this embodiment, the water temperature in the circulating water pipeline 17 is 25°C. The main tank body is preheated by using the temperature control jacket 16. At the same time, the vacuum pipeline 15 of the main tank body is opened to keep the vacuum degree in the main tank body in the range of -0.05 to -0.1MPa. In this embodiment, the internal vacuum degree is controlled to -0.07MPa.

[0059] Then, the slurry inlet pipeline 13 is opened, and the steam inlet pipeline 14 is opened at the same time, and the slurry is sent into the pipe from the top of the main tank body. The slurry is transmitted through the staggered serpentine channels of the staggered horizontal circular plates 121, and the flow area of ​​the slurry is spread through the non-porous inclined baffles 122 arranged on the horizontal circular plates 121 and the circular small baffles 124 of the exhaust holes 123; the steam is introduced in the reverse direction from the exhaust holes 123 and fully contacts with the flowing and spreading slurry material, so that the AN monomer in the slurry is fully dissolved to achieve liquid-gas two-phase separation treatment, and the AN monomer in the slurry is dissolved in the steam and then extracted through the monomer mixed steam outlet pipeline 24 at the top for subsequent water and AN monomer two-phase separation;

[0060] The undissolved PAN residue in the slurry will evaporate. By opening the disc-type water mist spray device 22 on the top, the residual PAN in the slurry will be further dissolved under the action of water mist, flowing from the top of the tank body and settling and mixing into the slurry. At the same time, combined with the second tower plate 23 in the upper auxiliary tank 21, the evaporating residual PAN can be further captured, dissolved and refluxed.

[0061] Finally, the AN monomer mixed steam outlet pipeline 24 is extracted and collected at the top of the upper auxiliary tank 21, and the slurry raw material after AN monomer removal treatment is extracted and stored at the bottom of the lower auxiliary tank 31 to achieve liquid-gas two-phase separation treatment of AN monomer in the slurry.

[0062] Example 4

[0063] like Figure 1 As shown, a polyacrylonitrile slurry monomer removal device includes an acetonitrile separation unit 1, a transpiration PAN capture unit 2 and a slurry discharge unit 3, wherein the acetonitrile separation unit 1 is the main structure for phase separation of AN monomers, ensuring the liquid-gas two-phase separation of AN monomers in the slurry in the entire device; the transpiration PAN capture unit 2 and the slurry discharge unit 3 above are for cooperating with the middle section AN monomer removal separation process, realizing the capture and dissolution of a small amount of transpiration PAN in the slurry and the secondary fine separation of the escaped AN monomer in the treatment of the acetonitrile separation unit 1; the slurry discharge unit 3 below is a heating and storage structure, realizing the heating, storage and recovery functions of the slurry after phase separation treatment.

[0064] The acetonitrile separation unit 1 comprises a main tank 11 and a first tray 12, wherein a plurality of first trays 12 are arranged in a staggered manner in the main tank 11. In the present embodiment, 10 to 50 first trays 12 are evenly and staggeredly arranged in the main tank body. In the present embodiment, there are 35 first trays 12. A slurry inlet pipeline 13, a steam inlet pipeline 14, a vacuum pipeline 15 and a temperature control jacket 16 are arranged on the main tank 11. The temperature control jacket 16 is coated on the outer periphery of the main tank 11. The vacuum pipeline 15 is located in the middle of the side wall of the main tank body to control the vacuum degree. The slurry inlet pipeline 13 is arranged above the plurality of first trays 12, and the steam inlet pipeline 14 is arranged above the plurality of first trays 12. The inlet pipeline 14 is arranged below the multiple groups of first tower plates 12; a circulating water pipeline 17 is arranged in the temperature control jacket 16, and the distance between the circulating water pipeline 17 and the inner wall of the main tank body is 1 / 20-1 / 10 of the radius of the main tank body. The inner radius of the main tank body is 65 cm, and the diameter of the circulating water pipeline 17 in the jacket is 10 cm. The circulating water pipeline 17 is a reciprocating serpentine coil water channel structure, and the internal pipeline spacing of the circulating water pipeline 17 is 5 mm. The distance between the circulating water pipeline 17 and the inner wall of the main pipe is 5.5 cm. The inlet of the circulating water channel is arranged at the bottom of the jacket, and the outlet of the circulating water channel is arranged on the top side wall of the jacket on the side opposite to the inlet.

[0065] The first tower plate 12 includes a horizontal circular plate 121, the arc edge of the horizontal circular plate 121 is in contact with the inner wall of the main tank body, and the angle of the circular part of the horizontal circular plate 121 is 105°; the horizontal circular plate 121 is provided with an inclined baffle 122, which is obliquely inserted on the horizontal circular plate 121, and the angle between the inclined baffle 122 and the horizontal circular plate 121 is controlled in the range of 10°-60°, which is 15° in the present embodiment, and the connecting line between the inclined baffle 122 and the horizontal circular plate 121 is a perpendicular line to the midpoint of the radius of the entire semicircular surface of the horizontal circular plate 121, and its direction is parallel to the circular line of the horizontal circular plate 121. A plurality of exhaust holes 123 are provided on the horizontal circular plate 121, and the opening diameter of the exhaust holes 123 is controlled within the range of 0.5-5 cm. In the present embodiment, the diameter of the exhaust holes 123 is 2 cm. The exhaust holes 123 on the horizontal circular plate 121 fall within the vertical projection range of the inclined baffle 122. A small baffle 124 is provided above the exhaust holes 123 on the horizontal circular plate 121, and the opening angle of the small baffle 124 is controlled within the range of 10°-60°, which is 25° in the present embodiment. The vertical projection area of ​​the small baffle 124 coincides with the area of ​​the exhaust holes 123.

[0066] The transpiration PAN capture unit 2 includes an upper auxiliary tank 21 and a spray device 22. The upper auxiliary tank 21 is connected above the main tank 11. The upper auxiliary tank 21 is hemispherical. A monomer mixed steam outlet pipeline 24 is arranged on the top of the upper auxiliary tank 21. A disc-type spray device 22 with a water mist spray direction toward the top of the tank body is arranged in the upper auxiliary tank 21; the second tower plates 23 are staggeredly arranged below the spray device 22 in the upper auxiliary tank 21. The second tower plates 23 adopt the same structure as the first tower plates 12. The second tower plates 23 can be arranged in 2-5 groups. In this embodiment, there are 2 groups of second tower plates 23.

[0067] The slurry discharge unit 3 includes a lower auxiliary tank 31, which is connected to the bottom of the main tank 11. A temperature control jacket 32 ​​is provided on the outside of the lower auxiliary tank 31 to control the water temperature in the temperature control jacket 16 of the lower auxiliary tank 31 within the range of 25-60°C. In this embodiment, the temperature is not less than 35°C to maintain the proper viscosity and fluidity of the de-monomer slurry. The design structure and size of the temperature control jacket 32 ​​are consistent with the design of the temperature control jacket 16 of the main tank 11. The lower auxiliary tank 31 is hemispherical, and a slurry outlet pipeline 33 is provided at the bottom of the lower auxiliary tank 31. A vacuum pump is provided on the slurry outlet pipeline, and the extraction, recovery and storage of the AN de-monomer slurry after phase separation treatment are realized by driving the vacuum pump.

[0068] The upper auxiliary tank 21, the lower auxiliary tank 31 and the main tank body are connected by flange 4, and the first tower plate 12 and the main tank body are connected by a detachable slot type connection, which realizes the convenient disassembly and maintenance of the single removal device, and the phase separation process of the AN monomer can be flexibly combined and set, and the equipment is easy to produce.

[0069] The method of removing the single using the above device is as follows:

[0070] First, the circulating water pipeline 17 of the main tank body is opened. The temperature of the circulating water pipeline 17 is 25-60°C. In this embodiment, the water temperature in the circulating water pipeline 17 is 45°C. The main tank body is preheated by using the temperature control jacket 16. At the same time, the vacuum pipeline 15 of the main tank body is opened to keep the vacuum degree in the main tank body in the range of -0.05 to -0.1MPa. In this embodiment, the internal vacuum degree is controlled to -0.06MPa.

[0071] Then, the slurry inlet pipeline 13 is opened, and the steam inlet pipeline 14 is opened at the same time, and the slurry is sent into the pipe from the top of the main tank body. The slurry is transmitted through the staggered serpentine channels of the staggered horizontal circular plates 121, and the flow area of ​​the slurry is spread through the non-porous inclined baffles 122 arranged on the horizontal circular plates 121 and the circular small baffles 124 of the exhaust holes 123; the steam is introduced in the reverse direction from the exhaust holes 123 and fully contacts with the flowing and spreading slurry material, so that the AN monomer in the slurry is fully dissolved to achieve liquid-gas two-phase separation treatment, and the AN monomer in the slurry is dissolved in the steam and then extracted through the monomer mixed steam outlet pipeline 24 at the top for subsequent water and AN monomer two-phase separation;

[0072] The undissolved PAN residue in the slurry will evaporate. By opening the disc-type water mist spray device 22 on the top, the residual PAN in the slurry will be further dissolved under the action of water mist, flowing from the top of the tank body and settling and mixing into the slurry. At the same time, combined with the second tower plate 23 in the upper auxiliary tank 21, the evaporating residual PAN can be further captured, dissolved and refluxed.

[0073] Finally, the AN monomer mixed steam outlet pipeline 24 is extracted and collected at the top of the upper auxiliary tank 21, and the slurry raw material after AN monomer removal treatment is extracted and stored at the bottom of the lower auxiliary tank 31 to achieve liquid-gas two-phase separation treatment of AN monomer in the slurry.

[0074] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0075] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A polyacrylonitrile slurry single-drying device, characterized in that: It comprises an acetonitrile separation unit, a transpiration PAN capture unit and a slurry discharge unit. The acetonitrile separation unit comprises a main tank and a first tower plate. A plurality of first tower plates are arranged in a staggered manner in the main tank. A slurry inlet pipeline, a steam inlet pipeline, a vacuum pipeline and a temperature control jacket are arranged on the main tank. The temperature control jacket is coated on the outer periphery of the main tank. The vacuum pipeline is used to control the pressure in the main tank. The slurry inlet pipeline is arranged above the steam inlet pipeline. The transpiration PAN capture unit comprises an upper auxiliary tank and a spray device. The upper auxiliary tank is connected above the main tank. The spray device is arranged in the upper auxiliary tank. A monomer mixed steam outlet pipeline is arranged on the top of the upper auxiliary tank. The slurry discharge unit comprises a lower auxiliary tank. The lower auxiliary tank is connected below the main tank. A slurry outlet pipeline is arranged on the lower auxiliary tank.

2. The polyacrylonitrile slurry removing device according to claim 1, characterized in that: The first tower plate comprises a horizontal circular notch plate, the arc edge of the horizontal circular notch plate contacts the inner wall of the main tank body, and the angle of the circular notch portion of the horizontal circular notch plate is 90°-170°.

3. The polyacrylonitrile slurry removing device according to claim 2, characterized in that: The horizontal circular plate is detachably provided with an inclined baffle, the angle between the inclined baffle and the horizontal circular plate is 10°-60°, the horizontal circular plate is provided with an exhaust hole, the exhaust port on the horizontal circular plate is within the vertical projection range of the inclined baffle, the connecting line between the inclined baffle and the horizontal circular plate is parallel to the chord corresponding to the two end points of the arc on the horizontal circular plate.

4. The polyacrylonitrile slurry removing device according to claim 2, characterized in that: The horizontal circular plate is provided with a small baffle above each exhaust hole, and the vertical projection area of ​​the small baffle coincides with the area of ​​the corresponding exhaust hole.

5. The polyacrylonitrile slurry removing device according to claim 1, characterized in that: A circulating water pipeline is arranged in the temperature control jacket. The circulating water pipeline is arranged in a spiral or reciprocating serpentine coil. The inlet of the circulating water pipeline is arranged at the bottom of the jacket, and the outlet of the circulating water pipeline is arranged at the top of the jacket on the side opposite to the inlet.

6. The polyacrylonitrile slurry removing device according to claim 1, characterized in that: The upper auxiliary tank is connected to a spray device via a water mist inlet pipeline, and the spray device sprays toward the monomer mixed steam outlet pipeline.

7. The polyacrylonitrile slurry removing device according to claim 1, characterized in that: The upper auxiliary tank is provided with second trays arranged in a staggered manner, and a plurality of the second trays are arranged between the spray device and the main tank.

8. The polyacrylonitrile slurry removing device according to claim 1, characterized in that: The outer periphery of the lower auxiliary tank is provided with a temperature-control jacket, and a vacuum pump is arranged on the slurry outlet pipeline.

9. The polyacrylonitrile slurry removing device according to claim 1, characterized in that: The upper auxiliary tank, the lower auxiliary tank and the main tank body are connected by flanges, and the first tower plate and the main tank body are connected by a detachable slot type connection.

10. A method for removing singles using the device according to any one of claims 1 to 9.

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