A device for dewatering a polyacrylonitrile slurry

Abstract

The application discloses a kind of polyacrylonitrile slurry's dehydration treatment device, including main cylinder, vacuum separation component and slurry tank.The cylinder wall of main cylinder is provided with through hole, and outer surface is provided with at least two filter layers covering through hole.A part of vacuum separation component is arranged in main cylinder, for vacuumizing in main cylinder.Slurry tank is used to contain polyacrylonitrile slurry material;Main cylinder is rotatably arranged in slurry tank, and is adsorbed on the surface of filter layer by negative pressure generated by vacuumizing polyacrylonitrile powder, the present application is by at least two filter layers on the surface of main cylinder, and vacuum separation component for vacuumizing inside main cylinder, can utilize the pressure difference inside and outside main cylinder, and polyacrylonitrile slurry in slurry tank is adsorbed on the surface of filter layer, and efficient solid-liquid separation is realized by filter layer.

Description

Technical Field

[0001] This invention relates to a dehydration treatment device for polyacrylonitrile slurry, belonging to the field of polyacrylonitrile powder preparation technology. Background Technology

[0002] Carbon fiber has many excellent properties such as low density, high specific strength, high specific modulus, high temperature resistance, and corrosion resistance. Among them, polyacrylonitrile (PAN) based carbon fiber has the characteristics of simple preparation process, low production cost and excellent mechanical properties, making it the fastest developing, highest-yielding, most diverse and widely used carbon fiber product.

[0003] The key raw material for producing PAN-based carbon fiber is high-performance PAN precursor fiber, and the quality of the precursor fiber is crucial to the quality of the carbon fiber. Currently, PAN precursor fiber is obtained through aqueous suspension polymerization of polyacrylonitrile followed by numerous processes. After aqueous polymerization, the resulting PAN slurry needs to be dehydrated to ensure that the PAN powder has a low moisture content. To ensure continuous operation of the entire process, a device for solid-liquid separation of PAN slurry with efficient dehydration effect needs to be designed to guarantee its high-efficiency dehydration treatment. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a dewatering treatment device for polyacrylonitrile slurry, which aims to improve the dewatering effect on polyacrylonitrile powder.

[0005] To achieve the above objectives, the present invention is implemented using the following technical solution: In a first aspect, the present invention provides a dewatering treatment apparatus for polyacrylonitrile slurry, comprising: The main cylinder has through holes in its wall and at least two filter layers covering the through holes on its outer surface. A vacuum separation component, part of which is located inside the main cylinder, is used to create a vacuum inside the main cylinder; A slurry tank is used to hold slurry material; the main cylinder is rotatably disposed in the slurry tank, and negative pressure is generated by vacuuming to adsorb the slurry material on the surface of the filter layer and dehydrate it.

[0006] Furthermore, the at least two filter layers include a rigid filter layer and a flexible filter layer arranged sequentially from the inside out; The rigid filter layer has a mesh density of 10-90% and a pore diameter of 5-20 mm; The diameter of the filter pores in the flexible filter layer is 10-100 μm.

[0007] Furthermore, the rigid filter layer is made of stainless steel mesh; The flexible filter layer is made of either cotton or synthetic fiber.

[0008] Furthermore, the flexible filter layer is fixed to the first filter layer by an array of fixed clips.

[0009] Furthermore, end caps for sealing the ports of the main cylinder are provided at both ends of the main cylinder along its axial direction; A main shaft and a support shaft are respectively connected to the axis of the two heads. The main shaft is rotatably connected to the slurry tank, and the support shaft is rotatably and sealingly connected to the heads through a rotary sealing joint. The spindle is connected to a motor for driving the spindle to rotate.

[0010] Furthermore, the vacuum separation assembly includes: At least one vacuum filtration tube is disposed inside the main cylinder, the vacuum filtration tube being close to the inner wall of the main cylinder and having a gap between it and the inner wall of the main cylinder for air to pass through. A main vacuum tube passes through the support shaft axially and is connected at one end to a vacuum filtration tube; the other end of the main vacuum tube extends to the outside of the main cylinder and is connected to a vacuum pump; when the vacuum pump is running, it creates a vacuum environment inside the main cylinder through the vacuum tube and the vacuum filtration tube.

[0011] Furthermore, the main cylinder is equipped with multiple vacuum tubes for filtration. Multiple vacuum filtration tubes are evenly spaced around the axis of the main cylinder and are all connected to the main vacuum tube.

[0012] Furthermore, the pore size of the filter holes on the surface of the vacuum filter tube is 2-10 mm, and the pore density is 30-60% of the surface area of ​​the side wall of the vacuum filter tube.

[0013] Furthermore, the edge of the slurry tank is provided with a scraper that is in close contact with the surface of the filter layer, which is used to scrape the dewatered slurry from the surface of the filter layer when the main cylinder rotates.

[0014] Furthermore, a diversion plate is provided on one side of the scraper to collect the dewatered slurry scraped by the scraper.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: This invention provides a dewatering treatment device for polyacrylonitrile slurry. By setting at least two filter layers on the surface of the main cylinder and a vacuum separation component for evacuating the inside of the main cylinder, the polyacrylonitrile slurry in the slurry tank can be adsorbed onto the surface of the filter layers by utilizing the pressure difference between the inside and outside of the main cylinder, and efficient solid-liquid separation can be achieved through the filter layers.

[0016] This invention provides a dewatering treatment device for polyacrylonitrile slurry, comprising at least two filter layers, including a rigid filter layer and a flexible filter layer arranged sequentially from the inside out. The rigid filter layer has a mesh density of 10-90% and a pore diameter of 5-20 mm; the flexible filter layer has a pore diameter of 10-100 μm, thereby enabling multi-stage filtration. Through the arrangement of the pore array structure of different levels of filter layers, a higher degree of adsorption, filtration, and solid-liquid phase separation effect on the slurry can be achieved. Furthermore, the second filter layer uses a flexible filter cloth material, which can be flexibly replaced according to the filtration effect.

[0017] The present invention provides a dewatering treatment device for polyacrylonitrile slurry. By setting a scraper close to the surface of the filter layer at the edge of the slurry tank, the scraper can scrape off the polyacrylonitrile powder on the surface of the filter layer when the main cylinder rotates, thereby realizing continuous extraction of dewatered polyacrylonitrile powder and improving overall production efficiency.

[0018] The present invention provides a dewatering treatment device for polyacrylonitrile slurry. By setting a vacuum filtration tube in the main cylinder, and multiple vacuum filtration tubes can be set, the vacuum filtration tubes have a widely distributed pore structure, thereby providing a uniformly distributed negative pressure driving force to the multi-stage filtration layer on the outer surface of the main cylinder, thus ensuring the uniformity of slurry dewatering. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the polyacrylonitrile sludge dewatering treatment device provided in an embodiment of the present invention; Figure 2 This is a side view of the polyacrylonitrile slurry dewatering treatment device provided in an embodiment of the present invention; In the diagram, 1. Main cylinder; 2. Through hole; 3. End cap; 4. First filter layer; 5. Second filter layer; 6. Fixing buckle; 7. Vacuum filtration tube; 8. Main vacuum tube; 9. Support shaft; 10. Vacuum pump; 11. Rotary sealing joint; 12. Motor; 13. Main shaft; 14. Slurry tank; 15. Slurry material; 16. Scraper; 17. Polyacrylonitrile powder; 18. Drainage plate; 19. Water; 20. Agitator. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0021] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0022] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances. Example

[0023] Please see Figure 1 This embodiment describes a dewatering treatment device for polyacrylonitrile slurry, including: a main cylinder 1, a vacuum separation component and a slurry tank 14.

[0024] The main cylinder 1 has through holes 2 in its wall, and at least two filter layers covering the through holes 2 are provided on its outer surface. A portion of the vacuum separation assembly is disposed inside the main cylinder 1 for evacuating the main cylinder 1. The slurry tank 14 is used to contain polyacrylonitrile slurry 15; the main cylinder 1 is rotatably disposed in the slurry tank 14, and the slurry 15 is adsorbed and dehydrated on the surface of the filter layers by creating negative pressure through vacuum evacuation, thereby obtaining dehydrated slurry 15, i.e., polyacrylonitrile powder 17. In this embodiment, the liquid level of the slurry 15 is preferably immersing 30-60% of the radius of the main cylinder 1.

[0025] In addition, in order to efficiently extract the attached polyacrylonitrile powder, in this embodiment, a scraper 16 is provided at the edge of the slurry tank 14, which is closely attached to the surface of the filter layer. The scraper 16 is used to scrape the polyacrylonitrile powder 17 from the surface of the filter layer when the main cylinder 1 rotates.

[0026] Further, please refer to Figure 2In conjunction with the aforementioned scraper 16, an inclined guide plate 18 is provided on one side of the scraper 16, allowing the polyacrylonitrile powder 17 scraped by the scraper 16 to flow laterally along the guide plate 18, making it convenient for workers to collect.

[0027] Specifically, please refer to Figure 2 In this embodiment, the main cylinder 1 is a hollow cylindrical tube with a diameter ranging from 800mm to 2m, which can be flexibly adjusted according to usage requirements; the length of the main cylinder 1 is ranging from 1 to 10m. The through holes on the surface of the main cylinder 1 are arranged in an array. Both ends of the main cylinder 1 along its axial direction are provided with metal end caps 3 for sealing the ports of the main cylinder 1. In this embodiment, the metal material can be stainless steel. A main shaft 13 and a support shaft 9 are respectively connected to the axis of the two end caps 3. The main shaft 13 is rotatably connected to the slurry tank 14 and fixedly connected to the end caps 3. The support shaft 9 is rotatably and sealingly connected to the end caps 3 through a rotary sealing joint 11. A motor 12 is connected to the main shaft 13 to drive its rotation. When the main shaft 13 rotates, it can drive the main cylinder 1 to rotate. In this embodiment, the rotation speed of the main cylinder 1 is controlled between 1 and 10 rpm.

[0028] In addition, please see Figure 1 In this embodiment, the at least two filter layers include a first filter layer 4 and a second filter layer 5 arranged sequentially from the inside out. The first filter layer 4 is a stainless steel filter screen, which can also be a filter plate in other embodiments. The second filter layer 5 is a flexible filter cloth, specifically a cotton cloth or a chemical fiber cloth, and is arranged in one or more layers. The mesh density of the first filter layer 4 is 10-90%, and the pore diameter is 5-20 mm; the pore diameter of the second filter layer 5 is 10-100 μm.

[0029] Furthermore, the second filter layer 5 is wrapped in a strip or is entirely wrapped around the surface of the main cylinder 1 according to its length. The filter cloth can be one or more layers, and is fixed to the surface of the stainless steel filter mesh of the first filter layer 4 of the main cylinder 1 by an array of pin-shaped fixing buckles 6, so as to ensure that the flexible filter cloth does not slip when the main cylinder 1 rotates.

[0030] Specifically, please refer to Figure 1The vacuum separation assembly includes a vacuum filtration tube 7, a main vacuum tube 8, and a vacuum pump 10. One or more vacuum filtration tubes 7 can be provided. When multiple vacuum filtration tubes 7 are provided, they are evenly spaced circumferentially around the axis of the main cylinder 1. Their diameter is controlled between 20-50 mm, and the surface of the vacuum filtration tube is covered with circular holes with a diameter ranging from 2-10 mm, with a pore density of 30-60% of the side area of ​​the vacuum filtration tube. The vacuum filtration tube 7 is located inside the main cylinder 1 and close to its inner surface. The main vacuum tube 8 extends from the vacuum filtration tube 7 and connects to a support shaft 9 on one side of the main cylinder 1. The main vacuum tube 8 passes through the support shaft 9 and connects to the vacuum pump 10. The operation of the vacuum pump 10 creates a vacuum environment inside the main cylinder 1, with the vacuum degree controlled between 0.06-0.1 MPa.

[0031] The present invention adopts a cooperative component structure of main vacuum tube 8, support shaft 9, and rotary sealing joint 11. This structure provides a stable negative pressure vacuum driving force for the entire main cylinder 1 through the main vacuum tube 8, supports a stable assembly structure at one end of the main cylinder 1 through the support shaft 9, and maintains a stable high vacuum level inside the main cylinder 1 through the rotary sealing joint 11 while providing stable support and allowing the main cylinder 1 to rotate.

[0032] In this embodiment, the slurry tank 14 is a rectangular trough structure, and its length, width and height can be flexibly matched and designed according to the size of the main cylinder 1. The slurry tank 14 is filled with a PAN water-powder mixture to be treated, i.e. slurry material 15, wherein the liquid surface of the PAN water-powder mixture submerges 30-60% of the radius of the main cylinder.

[0033] It should be added that the slurry tank 14 is equipped with a stirring device 20, which stirs the PAN water-powder mixture in the entire slurry tank 14 at a uniform speed to form slurry material 15.

[0034] The dewatering treatment device for polyacrylonitrile slurry provided in this embodiment involves the following steps in its application process: First, the motor 12 is turned on, and the main cylinder 1 rotates at a set speed, adhering the slurry material 15 in the slurry tank 14 to the second filter layer 5 on the surface of the main cylinder 1.

[0035] Second, the vacuum pump 10 of the vacuum separation component is turned on simultaneously. Under its action, the vacuum filtration tube 7 inside the main cylinder 1 performs filtration inside the main cylinder 1. At this time, the water 19 in the slurry 15 adhering to the surface of the second filter layer 5 is sucked into the main cylinder 1 under vacuum. The water that has undergone solid-liquid separation treatment flows back into the slurry tank 14.

[0036] Third, the polyacrylonitrile powder 17 adhering to the surface of the second filter layer 5, after solid-liquid separation, rotates to the other side of the surface of the main cylinder 1 as the main cylinder 1 rotates, and is scraped off by the scraper 16 that is close to the surface of the main cylinder 1, and collected by the diversion plate 18.

[0037] After the above-mentioned water washing treatment, the moisture content of the slurry material 15 formed by the PAN water-powder mixture is reduced from the original 400-600% to 40-80%.

[0038] The following describes the contents involved in the above embodiments in conjunction with several preferred embodiments. Example

[0039] The dewatering device for polyacrylonitrile slurry provided in this embodiment is as follows: First, a main cylinder 1 with a diameter of 800 mm and a length of 1 m is used as the main washing component. A vacuum separation assembly is connected to the other side of the main cylinder 1 and supported by a rotary sealing joint 11. Vacuum treatment is then performed inside the main cylinder 1. The surface of the main cylinder 1 adopts an array of 20 mm diameter through-holes with a pore density of 20%. A stainless steel filter screen with a pore density of 10% and a pore diameter of 5 mm is wrapped around the surface of the main cylinder 1 as the first filter layer 4. A layer of cotton cloth with a pore size of 10 μm is wrapped around the outer surface of the filter screen as the second filter layer 5. This filter cloth can be wrapped around the surface of the main cylinder 1 in a strip-like winding manner. This layer is fixed to the surface of the stainless steel filter screen of the main cylinder 1 using an array of pin-shaped fixing buckles 6. The main cylinder 1 is equipped with a vacuum separation assembly. The main body of this device is a vacuum filtration tube 7 with a diameter of 20 mm. The surface of the vacuum filtration tube 7 is distributed with round holes with a pore size of 2 mm, and the pore density is 30% of the side area of ​​the vacuum filtration tube 7. The main vacuum tube is led out from a specific position of the vacuum filtration tube 7. The main vacuum tube is connected to the connecting support shaft on one side of the main cylinder 1. The main vacuum tube passes through the support shaft and is connected to the vacuum pump. The vacuum pump creates a vacuum environment with a vacuum degree of 0.06MPa inside the main cylinder 1.

[0040] The slurry tank 14 is a rectangular trough-shaped structure with a length of 1.5m, a width of 0.9m, and a height of 0.5m. The surface of the main cylinder 1 is close to one of the long sides of the slurry tank 14. The slurry tank 14 contains slurry material 15 to be treated and is equipped with a stirring device 20. The liquid level of the slurry material 15 submerges 30% of the radius of the main cylinder 1. A scraper 16 is provided on the edge of the slurry tank 14, which is close to the surface of the main cylinder 1, to scrape off the polyacrylonitrile powder 17 that has undergone solid-liquid phase separation treatment on the surface of the second filter layer 5. The scraper is then collected by a guide plate 18. Under the negative pressure provided by the vacuum separation component, the water in the slurry material 15 is adsorbed into the interior of the main cylinder 1 and then flows into the slurry tank 14. After being treated by the above-mentioned dewatering device, the water content of the slurry material 15 is reduced from 400% to 40%. Example

[0041] The specific details of the dewatering treatment device for polyacrylonitrile slurry provided in this embodiment are as follows: First, a main cylinder 1 with a diameter of 2m and a length of 10m is used as the main washing component. A vacuum separation assembly is connected to the other side of the main cylinder 1 and supported by a rotary sealing joint 11 to perform vacuum treatment inside the main cylinder 1. The surface of the main cylinder 1 adopts an array-type through-hole design with a diameter of 50mm and a pore density of 30%. A filter plate with a pore density of 90% and a pore diameter of 20mm is covered on the surface of the main cylinder 1 as the first filter layer 4. Four layers of chemical fiber cloth with a pore diameter of 100μm are covered on the outer surface of the filter plate as the second filter layer 5. The filter cloth can be used to cover the surface of the main cylinder 1 in a whole length of 10m. This layer is fixed to the surface of the stainless steel filter plate of the main cylinder 1 using an array-type pin-shaped fixing buckle 6. The vacuum separation assembly is provided inside the main cylinder 1. The main body of the device consists of two vacuum suction tubes 7 with a diameter of 50mm. The surface of the vacuum suction tubes 7 is distributed with round holes with a pore diameter of 10mm, and the pore density is 60% of the side area of ​​the vacuum suction tubes 7. A vacuum environment with a vacuum degree of 0.1 MPa is created inside the main cylinder 1 by operating the vacuum pump 10.

[0042] The surface of the main cylinder 1 is close to one side of the length of the slurry tank 14. The slurry tank 14 is a rectangular trough structure with a length of 12m, a width of 2.5m, and a height of 1.5m. The slurry tank 14 contains slurry material 15 to be treated and is equipped with a stirring device. The liquid level of the slurry material 15 submerges 60% of the radius of the main cylinder 1. A scraper 16 is provided on the edge of the slurry tank 14, which is close to the surface of the main cylinder 1, to scrape off the polyacrylonitrile powder 17 that has undergone solid-liquid phase separation treatment on the surface of the second filter layer 5. The scraper collects the powder through a guide plate. Under the negative pressure provided by the vacuum separation component, the water in the water-powder mixture is adsorbed into the interior of the main cylinder 1 and flows into the slurry tank 14. After being treated by the above-mentioned dehydration treatment device, the water content of the slurry material 15 is reduced from 600% to 80%. Example

[0043] The specific details of the dewatering treatment device for polyacrylonitrile slurry provided in this embodiment are as follows: First, a main cylinder 1 with a diameter of 1m and a length of 6m is used as the main washing component. A vacuum separation assembly is connected to the other side of the main cylinder 1 and supported by a rotary sealing joint, allowing for vacuum treatment inside the main cylinder 1. The surface of the main cylinder 1 features an array of 30mm diameter through holes with a pore density of 25%. A stainless steel filter screen with a pore density of 70% and a pore diameter of 10mm is wrapped around the surface of the main cylinder 1. Three layers of cotton cloth with a pore size of 50μm are then wrapped around the outer surface of the filter screen. This filter cloth can be wrapped in a strip-like manner on the surface of the main cylinder 1, and this layer is fixed to the surface of the stainless steel filter screen using an array of pin-shaped fixing clips. The vacuum separation assembly is located inside the main cylinder 1. The main body of this device consists of three 40mm diameter vacuum filtration tubes 7. The surface of the vacuum filtration tubes 7 is distributed with 7mm diameter circular holes, and the pore density is 40% of the side area of ​​the vacuum filtration tubes 7. A vacuum environment with a vacuum degree of 0.08 MPa is created inside the main cylinder 1 by operating the vacuum pump 10.

[0044] The surface of the main cylinder 1 is close to one side of the length of the slurry tank 14. The slurry tank 14 is a rectangular trough structure with a length of 7m, a width of 1.5m, and a height of 0.6m. The slurry tank 14 contains slurry material 15 to be treated and is equipped with a stirring device. The liquid level of the slurry material 15 submerges 45% of the radius of the main cylinder 1. A scraper 16 is provided on the edge of the slurry tank 14, which is close to the surface of the main cylinder 1, to scrape off the polyacrylonitrile powder 17 that has undergone solid-liquid phase separation treatment on the surface of the second filter layer 5. The scraper is then collected by a guide plate 18. Under the negative pressure provided by the vacuum separation component, the water in the slurry material 15 is adsorbed into the interior of the main cylinder 1 and flows into the slurry tank 14. After being treated by the above-mentioned dewatering device, the water content of the slurry material 15 is reduced from 500% to 45%. Example

[0045] The specific details of the dewatering treatment device for polyacrylonitrile slurry provided in this embodiment are as follows: First, a main cylinder 1 with a diameter of 900 mm and a length of 4 m is used as the main washing component. A vacuum separation assembly is connected to the other side of the main cylinder 1 and supported by a rotary sealing joint, and a vacuum is applied to the inside of the main cylinder 1. The surface of the main cylinder 1 adopts an array of 42 mm diameter through holes with a pore density of 28%. A stainless steel filter screen with a pore density of 60% and a pore diameter of 15 mm is wrapped on the surface of the main cylinder 1. Six layers of chemical fiber cloth with a pore size of 40 μm are then wrapped around the filter screen. This filter cloth can be wrapped in a strip-like winding form on the surface of the main cylinder 1, and this layer is fixed to the surface of the stainless steel filter screen using an array of pin-shaped fixing clips. The vacuum separation assembly is located inside the main cylinder 1. The main body of this device is a vacuum filtration tube 7 with a diameter of 35 mm. The surface of the vacuum filtration tube 7 is distributed with circular holes with a pore size of 3 mm, and the pore density is 35% of the side area of ​​the vacuum filtration tube 7. A vacuum environment with a vacuum degree of 0.09 MPa is created inside the main cylinder 1 by operating the vacuum pump 10.

[0046] The surface of the main cylinder 1 is close to one side of the length of the slurry tank 14. The slurry tank 14 is a rectangular trough structure with a length of 4.5m, a width of 1m, and a height of 0.5m. The slurry tank 14 contains slurry material 15 to be treated and is equipped with a stirring device. The liquid level of the slurry material 15 submerges 40% of the radius of the main cylinder 1. A scraper 16 is provided on the edge of the slurry tank 14, which is close to the surface of the main cylinder 1, to scrape off the polyacrylonitrile powder 17 that has undergone solid-liquid phase separation treatment on the surface of the second filter layer 5. The scraper is then collected by a guide plate 18. Under the negative pressure provided by the vacuum separation component, the water in the water-powder mixture is adsorbed into the interior of the main cylinder 1 and flows into the slurry tank 14. After being treated by the above-mentioned dehydration treatment device, the water content of the slurry material 15 is reduced from 550% to 45%.

[0047] In summary, after the above dewatering treatment, the moisture content of the slurry 15 is reduced from the original 400-600% to 40-80%.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure and not to limit its protection scope. Although this disclosure has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading this disclosure, they can still make various changes, modifications or equivalent substitutions to the specific implementation of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims.

Claims

1. A dewatering treatment device for polyacrylonitrile slurry, characterized in that, include: The main cylinder has through holes in its wall and at least two filter layers covering the through holes on its outer surface. A vacuum separation component, part of which is located inside the main cylinder, is used to create a vacuum inside the main cylinder; A slurry tank is used to hold slurry material; the main cylinder is rotatably disposed in the slurry tank, and negative pressure is generated by vacuuming to adsorb the slurry material on the surface of the filter layer and dehydrate it.

2. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 1, characterized in that, The at least two filter layers include a rigid filter layer and a flexible filter layer arranged sequentially from the inside to the outside. The rigid filter layer has a mesh density of 10-90% and a pore diameter of 5-20 mm; The diameter of the filter pores in the flexible filter layer is 10-100 μm.

3. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 2, characterized in that, The rigid filter layer is made of stainless steel mesh. The flexible filter layer is made of either cotton or synthetic fiber.

4. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 3, characterized in that, The flexible filter layer is fixed to the first filter layer by an array of fixed clips.

5. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 1, characterized in that, Both ends of the main cylinder are provided with end caps to close the ports of the main cylinder. A main shaft and a support shaft are respectively connected to the axis of the two heads. The main shaft is rotatably connected to the slurry tank, and the support shaft is rotatably and sealingly connected to the heads through a rotary sealing joint. The spindle is connected to a motor for driving the spindle to rotate.

6. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 5, characterized in that, The vacuum separation component includes: At least one vacuum filtration tube is disposed inside the main cylinder, the vacuum filtration tube being close to the inner wall of the main cylinder and having a gap between it and the inner wall of the main cylinder for air to pass through. A main vacuum tube passes through the support shaft axially and is connected at one end to a vacuum filtration tube; the other end of the main vacuum tube extends to the outside of the main cylinder and is connected to a vacuum pump; when the vacuum pump is running, it creates a vacuum environment inside the main cylinder through the vacuum tube and the vacuum filtration tube.

7. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 6, characterized in that, The main cylinder is equipped with multiple vacuum tubes for filtration. Multiple vacuum filtration tubes are evenly spaced around the axis of the main cylinder and are all connected to the main vacuum tube.

8. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 6, characterized in that, The pore size of the filter holes on the surface of the vacuum filter tube is 2-10 mm, and the pore density is 30-60% of the surface area of ​​the side wall of the vacuum filter tube.

9. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 1, characterized in that, The edge of the slurry tank is equipped with a scraper that is in close contact with the surface of the filter layer, which is used to scrape the dewatered slurry from the surface of the filter layer when the main cylinder rotates.

10. The dewatering treatment apparatus for polyacrylonitrile slurry according to claim 9, characterized in that, A diversion plate is provided on one side of the scraper to collect the dewatered slurry scraped by the scraper.

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