Polyacrylonitrile-based carbon fiber precursor washing turbulence device

Abstract

The utility model discloses a polyacrylonitrile-based carbon fiber precursor washing turbulence device. Two heating devices are mounted at the bottom of the inner side of a washing tank body; a pure water inlet or an upper-stage overflow port is formed in the right side of the bottom of the washing tank body, a water replenishing uniform distribution plate is mounted on the inner side of the right side wall of the washing tank body, the bottom end of the water replenishing uniform distribution plate is communicated with the pure water inlet or the upper-stage overflow port, and the direction of pure water replenished from the pure water inlet or the upper-stage overflow port is opposite to the running direction of the fiber conveying device; a pure water inlet or a current-stage overflow port is formed in the middle of the bottom end of the washing tank body, an n-shaped uniformly-distributed splitter plate is mounted in the middle of the washing tank body, and the lower side of the uniformly-distributed splitter plate is communicated with the pure water inlet or the current-stage overflow port through a uniformly-distributed splitter supporting plate. On the premise that the original performance of nascent fibers is not influenced, the washing process is optimized, the washing efficiency is improved, and the content of residual solvent in the fibers is reduced to below one percent, so that the subsequent carbon fiber production process is not influenced.

Description

Technical Field

[0001] The utility model relates to the technical field of water washing of polyacrylonitrile-based carbon fiber precursor, in particular to a water-washing turbulence device for polyacrylonitrile-based carbon fiber precursor. Background Art

[0002] One of the factors causing defects in PAN precursor yarns is the residual solvent in the precursor yarn. The residual solvent DMSO is an impurity in the fiber. When the residual solvent DMSO content is high, the appearance of the obtained precursor yarn becomes white, which is a typical skin-core structure. The formation of the skin-core structure seriously affects the final performance of the carbon fiber, and the residual solvent will cause the fiber to become twisted and sticky, which is one of the reasons for the surface defects of the carbon fiber. This surface defect causes a large amount of heat to accumulate during the subsequent processing of the fiber, which will cause large-scale wire breakage and roller winding, which will greatly reduce the quality and output of the carbon fiber and affect the safe production of carbon fiber.

[0003] To reduce the DMSO content in the raw silk, a water washing process is added after the coagulation process to remove residual solvent from the fiber. The water washing process is equivalent to a continuation of the coagulation process. Both processes reduce the solvent content in the fiber through a double diffusion process. The difference is that the fiber structure has already been formed during the water washing process, and the overall structure will not undergo significant changes during the water washing process. During the drying and heat setting process, the fiber will show yellowing and cross-sectional changes.

[0004] Conventional means, namely increasing the water washing temperature or extending the water washing time, will increase production costs in industrial production. Therefore, a low-cost process device is needed to improve the water washing efficiency. Utility Model Content

[0005] The purpose of this utility model is to provide a water-washing agitator for polyacrylonitrile-based carbon fiber precursors to address the shortcomings of existing water-washing technologies, such as low efficiency that affects the properties of the precursor, or the use of conventional solutions such as increasing the temperature and extending the washing time, which increases production costs. This utility model uses a water-washing agitator to improve the uniformity of water temperature, enhance the contact efficiency between the circulating water and the fibers, and ensure more thorough washing.

[0006] The utility model is realized through the following technical solutions:

[0007] A polyacrylonitrile-based carbon fiber precursor water-washing disturbance device comprises a water-washing tank body and a fiber transport device placed perpendicular to the water-washing tank body, an insulation layer is installed in the wall of the water-washing tank body, and two heating devices are installed at the bottom inner side of the water-washing tank body; a pure water inlet or an upper-level overflow port is provided on the right side of the bottom of the water-washing tank body, a water replenishment uniform distribution plate is installed on the inner side of the right side wall of the water-washing tank body, the bottom end of the water replenishment uniform distribution plate is connected with the pure water inlet or the upper-level overflow port, and the direction of pure water replenished from the pure water inlet or the upper-level overflow port is opposite to the running direction of the fiber transport device; a pure water inlet or an overflow port of this level is installed in the middle of the bottom end of the water-washing tank body, a "J"-shaped uniform distribution diverter plate is installed in the middle of the water-washing tank body, and the lower side of the "J"-shaped uniform distribution diverter plate is connected with the pure water inlet or the overflow port of this level through a uniform distribution diversion support plate; a return plate is installed on the left inner wall of the water-washing tank body; and an overflow port is provided on the upper left side of the water-washing tank body.

[0008] The fiber transport device comprises four transmission rollers and a power device thereof, and the fibers are transported by virtue of the friction between the fibers and the transmission rollers.

[0009] The heat-insulating layer adopts aluminum silicate fiber cotton or foamed plastic or vacuum heat-insulating.

[0010] The heating device adopts one of electric heating, steam heating, oil heating and high-pressure water heating.

[0011] The opening rate of the water replenishment uniform distribution plate is 5% to 40%.

[0012] Uniform openings are provided on the X-shaped uniform distribution plate and the uniform distribution support plate. The uniform openings on the X-shaped uniform distribution plate are holes with a length of 5mm~50mm and a width of 1mm~5mm, and the direction of the holes is aligned with the fiber bundles. The uniform openings on the uniform distribution support plate are holes with a length of 5mm~50mm and a width of 1mm~5mm, and a deflector with an inclination angle of 30° to 60° is arranged above the holes; both ends of the X-shaped uniform distribution plate are provided with fine flow openings, and the fine flow openings at both ends are respectively aligned with the two heating devices.

[0013] There are no fewer than three water-washing disruptors in the entire production line, and multiple such washing devices form a multi-stage water washing system. Multiple washing tanks are arranged in sequence, with the top tank connected to a water inlet pipe, and the bottom tank connected to a drainage pipe. The spun fiber first enters the bottom tank for washing, then enters the adjacent tanks, finishing washing in the top tank.

[0014] The advantages of the present invention are: the present invention adds a water washing turbulence device in the water washing link, optimizes the water washing process and improves the water washing efficiency without affecting the original properties of the nascent fiber, and reduces the residual solvent content in the fiber to less than 1%, so as not to affect the subsequent carbon fiber production process.

[0015] The utility model not only surpasses the water washing method used in the past, shortens the process, reduces the investment in water washing equipment and space, but also greatly improves production efficiency and enhances industrial utilization value. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural diagram of the utility model;

[0017] Figure 2 It is a partial structural diagram of the X-shaped uniformly distributed diverter plate of the utility model. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the embodiments of the present application Figure 1 、 Figure 2 , a clear and complete description of the technical solutions of the embodiments of this application is provided. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the described embodiments of this application, all other embodiments obtained by ordinary technicians in this field fall within the scope of protection of this application.

[0019] like Figure 1 、 2 As shown, a polyacrylonitrile-based carbon fiber precursor water-washing disturbance device includes a water-washing tank body 1 and a fiber transport device 2 placed perpendicular to the water-washing tank body 1, an insulation layer 3 is installed on the inner wall of the water-washing tank body 1, and two heating devices 4 are installed on the inner bottom of the water-washing tank body 1; a pure water inlet or an upper-level overflow port 5 is provided on the right side of the bottom of the water-washing tank body 1, and a water replenishment uniform distribution plate 6 is installed on the inner side of the right side wall of the water-washing tank body 1, and the bottom end of the water replenishment uniform distribution plate 6 is connected to the pure water inlet or the upper-level overflow port 5 The direction of pure water replenished from the pure water inlet or the overflow port 5 of the previous level is opposite to the running direction of the fiber transport device 2; a pure water inlet or the overflow port 7 of this level is installed in the middle of the bottom end of the water washing tank body 1, and a cross-shaped uniformly distributed diverter plate 8 is installed in the middle of the water washing tank body 1. The lower side of the cross-shaped uniformly distributed diverter plate 8 is connected to the pure water inlet or the overflow port 7 of this level through the uniformly distributed diverter support plate 9; a return plate 10 is installed on the left inner wall of the water washing tank body 1; an overflow port 11 is provided on the upper left side of the water washing tank body 1.

[0020] The fiber transport device 2 includes four transmission rollers and a power device. The fibers are transported by friction with the transmission rollers. The fiber running direction can be changed by rotating the rollers clockwise or counterclockwise.

[0021] The insulation layer 3 may be made of thermal insulation materials such as aluminum silicate fiber cotton, foamed plastic, etc., or may be vacuum-insulated to reduce heat loss in the washing tank 1 .

[0022] The heating device 4 can be heated by electric heating, steam heating, oil heating, high-pressure water heating, etc.

[0023] The opening rate of the water replenishment uniform distribution plate 6 is 5% to 40%, and the replenished pure water flows evenly to avoid dead zones.

[0024] Uniform openings 12 are provided on the X-shaped uniform distribution diverter plate 8 and the uniform distribution diverter support plate 9. The uniform openings on the X-shaped uniform distribution diverter plate 8 are holes with a length of 5mm~50mm and a width of 1mm~5mm. The direction of the holes is aligned with the fiber bundles to achieve a flushing effect. The uniform openings on the uniform distribution diverter support plate 9 are holes with a length of 5mm~50mm and a width of 1mm~5mm. A deflector 13 with an inclination angle of 30° to 60° is arranged above the holes to ensure that the flow direction is between 30° and 60°, thereby homogenizing the liquid in this area. Both ends of the X-shaped uniform distribution diverter plate 8 are provided with fine flow outlets 14, and the fine flow outlets 14 at both ends are respectively aligned with the two heating devices 4 to uniformly equalize the temperature in the water washing tank 1.

[0025] The water washing tank body 1 uses a pump to inject pure water or overflow liquid of this stage into the water washing tank body 1, and the injection is uniformly distributed.

[0026] The washing tank body 1 uses a baffle to return the overflow liquid again to rinse the fibers again.

[0027] The overflow liquid of the water washing tank 1 can enter the next stage of water washing or be directly discharged into the waste liquid recovery device.

[0028] The utility model disturbs the liquid in the entire washing tank body 1 through the arranged injection ports, baffles and return plates 10, so as to achieve the purpose of homogenizing the concentration and temperature of the liquid.

[0029] A set of fiber transport devices 2 are symmetrically installed above the washing tank 1. Each set of fiber transport devices 2 includes two transmission rollers. The upper transmission roller rotates clockwise, and the lower transmission roller rotates counterclockwise. The fibers are transported by friction with the transmission rollers, and the direction of fiber transportation is opposite to the direction of main water flow.

[0030] There are no less than three water washing turbulence devices in the entire production line, and multiple water washing flow devices are composed of multi-stage water washing.

[0031] The working principle of the utility model is: the liquid in the washing tank body 1 is heated by the heating device 4, and the electric pump is used to heat the liquid in the washing tank body 1. Figure 1Pure water is injected into the washing tank 1 through two pure water inlets: the pure water inlet or the previous overflow port 5 and the pure water inlet or the current overflow port 7. The water replenishment uniform distribution plate 6 connected to the pure water inlet or the previous overflow port 5 injects pure water into the washing tank 1 from right to left. The pure water inlet or the current overflow port 7 is connected to the cross-shaped uniform distribution plate 8 and the uniform distribution support plate 9, which are provided with angled uniform openings 12. Pure water entering the washing tank 1 through these openings disturbs the raw liquid in the tank, and the fine flow port 14 is aligned with the heating device 4 to even out the temperature in the tank. The injected pure water reaches the calibrated scale and then flows out through the overflow port 11, forming a dynamic circulation washing device. PAN raw fibers are immersed in the washing tank through the fiber running device. The concentration difference between the solvent inside the fiber and the liquid in the washing tank is used to remove the residual solvent in the raw fibers to the greatest extent possible.

[0032] The specific usage is:

[0033] 1. Turn on the electric pump to inject pure water into the washing tank 1 and turn on the heating device 4;

[0034] 2. Add the required solvent into the water washing tank 1 and wait until the concentration and temperature in the water washing tank 1 reach the required requirements;

[0035] 3. The raw silk is immersed in the liquid of the washing tank 1 through the fiber transport device 2. After the fiber is fully washed, it is transferred out through the fiber transport device 2 to enter the next process link.

[0036] The above is a preferred embodiment 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 principles described in the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A polyacrylonitrile-based carbon fiber precursor water-washing spoiler device, characterized by: It includes a water washing tank body and a fiber transportation device placed perpendicular to the water washing tank body, an insulation layer is installed in the wall of the water washing tank body, and two heating devices are installed at the bottom inner side of the water washing tank body; a pure water inlet or an upper-level overflow port is provided on the right side of the bottom of the water washing tank body, a water replenishment uniform distribution plate is installed on the inner side of the right side wall of the water washing tank body, the bottom end of the water replenishment uniform distribution plate is connected with the pure water inlet or the upper-level overflow port, and the direction of pure water replenished from the pure water inlet or the upper-level overflow port is opposite to the running direction of the fiber transportation device; a pure water inlet or the current-level overflow port is installed in the middle of the bottom end of the water washing tank body, a "J"-shaped uniform distribution diverter plate is installed in the middle of the water washing tank body, and the lower side of the "J"-shaped uniform distribution diverter plate is connected with the pure water inlet or the current-level overflow port through a uniform distribution diversion support plate; a return plate is installed on the left inner wall of the water washing tank body; and an overflow port is provided on the upper left side of the water washing tank body.

2. The polyacrylonitrile-based carbon fiber precursor water-washing spoiler device according to claim 1, characterized in that: The fiber transport device comprises four transmission rollers and a power device thereof, and the fibers are transported by virtue of the friction between the fibers and the transmission rollers.

3. The polyacrylonitrile-based carbon fiber precursor water-washing spoiler device according to claim 1, characterized in that: The heat-insulating layer adopts aluminum silicate fiber cotton or foamed plastic or vacuum heat-insulating.

4. The polyacrylonitrile-based carbon fiber precursor water-washing spoiler device according to claim 1, characterized in that: The heating device adopts one of electric heating, steam heating, oil heating and high-pressure water heating.

5. The polyacrylonitrile-based carbon fiber precursor water-washing spoiler device according to claim 1, characterized in that: The opening rate of the water replenishment uniform distribution plate is 5% to 40%.

6. The polyacrylonitrile-based carbon fiber precursor water-washing spoiler device according to claim 1, characterized in that: Uniform openings are provided on the X-shaped uniform distribution plate and the uniform distribution support plate. The uniform openings on the X-shaped uniform distribution plate are holes with a length of 5mm~50mm and a width of 1mm~5mm, and the direction of the holes is aligned with the fiber bundles. The uniform openings on the uniform distribution support plate are holes with a length of 5mm~50mm and a width of 1mm~5mm, and a deflector with an inclination angle of 30° to 60° is arranged above the holes; both ends of the X-shaped uniform distribution plate are provided with fine flow openings, and the fine flow openings at both ends are respectively aligned with the two heating devices.

Images