Nanofiber forming device

Abstract

The present invention is a nanofiber forming device, which is a fully enclosed structure, including an extended flow channel pulp distributor, a flow channel, and an adjustable upper lip plate mechanism connected in sequence; wherein the extended flow channel pulp distributor is a straight-up single-flow channel type, and the flow channel cross-sectional area perpendicular to the slurry flow direction gradually expands from a circular hole at the slurry inlet that is the same as the diameter of the slurry pipe to a rectangular area equal to that near the flow box, so as to ensure that the ultra-low concentration nanofiber slurry forms a stable isobaric distribution along the width direction; the flow channel inlet is rectangular, and the cross-sectional area further suddenly increases, and the height in the flow channel is adjustable; the adjustable upper lip plate mechanism can adjust the displacement, and while realizing local fine-tuning of the lip opening height, it can also make forward and backward translation adjustments. The present invention has a simple structure and is suitable for the formation of ultra-low concentration nanofiber slurry of 0.01%-0.05%. The fully enclosed structure can prevent the nanofibers from contacting the air, thereby avoiding the generation of a large number of bubbles. As the application of nanofibers in this hot field continues to heat up, it will have a huge market prospect.

Description

Technical Field

[0001] The present invention relates to a nanofiber forming device, which is mainly used in the production field of special materials (such as nanofiber diaphragm materials, nano-aramid materials, nano-carbon nanotube materials, etc.) using nanofibers as raw materials. Background Art

[0002] Special material properties have become a new hot spot for development at home and abroad. Nanofibers can be used to enhance composite materials, such as carbon nanofibers and carbon nanotubes, and can also be used in high-efficiency filter media, which can significantly improve filtration efficiency. They can also be used in the biomedical field, precision electronics and optical devices. These new fields have huge market potential. Therefore, nanofiber forming is a problem that needs to be solved urgently. Summary of the invention

[0003] The present invention provides a forming device for nanofiber raw materials, which is suitable for forming ultra-low-concentration nanofiber slurry of 0.01%-0.05%. The device is a fully enclosed structure, including an extended flow channel pulp distributor, a flow channel, and an adjustable upper lip plate mechanism connected in sequence; wherein the extended flow channel pulp distributor is a vertical single-flow channel type, and the flow channel cross-sectional area perpendicular to the slurry flow direction gradually expands from a circular hole at the slurry inlet that is the same as the diameter of the slurry pipe to a rectangular area equal to that near the slurry headbox, so as to ensure that the ultra-low-concentration nanofiber slurry forms a stable isobaric distribution along the width direction; the flow channel inlet is rectangular , the cross-sectional area further suddenly increases, so as to prevent fiber flocculation, promote fiber dispersion and improve the forming uniformity. Moreover, the height in the flow channel can be adjusted, so as to increase or decrease the speed of the pulp flow and improve the adaptability of the headbox to the process. The adjustable upper lip plate mechanism can adjust the displacement, and while realizing the local fine adjustment of the lip opening height, it can also make forward and backward translation adjustment, so as to appropriately control the direction and position of the pulp flow on the net, which is more conducive to the forming of nanofiber slurry, and it is easier to eliminate liquid level fluctuations, control the pulp flow trajectory, improve the longitudinal stability of the pulp flow, and is more conducive to improving the forming uniformity.

[0004] As a preferred solution, the horizontal inclination angle of the vertical single flow channel of the extended flow channel pulp distributor is less than or equal to 60°. If the inclination angle is too large, it will cause too rapid expansion, which will cause the pulp flow to separate and generate vortices at the side walls, causing further fiber flocculation.

[0005] As a preferred solution, the adjustable range of the flow channel height is 5mm-80mm. By adjusting the height of the flow channel, the adaptability of the headbox to the process is improved.

[0006] The invention is a special material for producing nanofiber raw materials, has a simple structure, and is particularly suitable for the research and development of new products of nanofiber raw materials. Due to the special material properties of nanofibers such as a large specific surface area, the higher the concentration, the easier it is to flocculate and generate a large number of bubbles. Therefore, in order to improve the forming uniformity quality of nanofibers, the best method is to adopt ultra-low concentration forming and a fully enclosed structure. In the slurry forming process, on the one hand, the use of 0.01%-0.05% ultra-low concentration forming can reduce the flocculation between nanofibers. This forming concentration is one tenth or even one hundredth of the traditional papermaking forming concentration. On the other hand, the use of a fully enclosed structure can prevent the nanofibers from contacting the air, thereby avoiding the generation of a large number of bubbles. As the application of nanofibers in this hot field continues to heat up, it will have a huge market prospect.

[0007] Description of the drawings.

[0008] Figure 1 It is a structural schematic diagram of the present invention.

[0009] In the figure: 1. Extended flow channel slurry distributor; 2. Flow channel; 3. Adjustable upper lip plate mechanism; 4. Extended flow channel slurry distributor inlet; 5. Lip.

[0010] Specific implementation method.

[0011] A nanofiber forming device is mainly used for forming nanofiber raw materials. The device is suitable for forming ultra-low concentration nanofiber slurry of 0.01%-0.05%. It is a fully enclosed structure, including an extended flow channel slurry distributor, a flow channel, and an adjustable upper lip plate mechanism connected in sequence; the extended flow channel slurry distributor is a vertical single flow channel type, welded from stainless steel, does not deform, has stable dimensions, a smooth inner wall without slurry hanging, and is easy to clean. The cross-sectional area of ​​the flow channel of the extended flow channel distributor perpendicular to the slurry flow direction gradually expands from a circular hole at the slurry inlet that is the same as the diameter of the slurry pipe to a rectangular area equal to that near the flow box, so as to ensure that the ultra-low concentration nanofiber slurry forms a stable isobaric distribution along the width direction; the flow channel inlet is rectangular, and the cross-sectional area further suddenly increases, so as to prevent fiber flocculation, promote fiber dispersion, and improve the forming uniformity, and the height in the flow channel can be adjusted, thereby accelerating or decelerating the slurry flow and improving the adaptability of the flow box to the process; the adjustable upper lip plate mechanism can adjust the displacement, and while realizing local fine-tuning of the lip opening height, it can also make forward and backward translation adjustments, so as to appropriately control the direction and position of the upper slurry flow, which is more conducive to the forming of nanofiber slurry, and is easier to eliminate liquid level fluctuations, control the slurry flow trajectory, improve the longitudinal stability of the slurry flow, and is more conducive to improving the forming uniformity.

[0012] The ultra-low-concentration nanofiber slurry flows in from the inlet 4 of the extended flow channel distributor. The slurry gradually expands along the cross-sectional area of ​​the flow channel perpendicular to the slurry flow direction to form a stable isobaric distribution. Each stream has the same pressure loss and enters the flow channel 2 evenly distributed over the entire width. The inlet of the flow channel 2 is rectangular, and the cross-sectional area is further expanded, and the cross-sectional area is abrupt, similar to the role of a step diffuser, to prevent fiber flocculation and promote fiber dispersion, providing favorable conditions for forming. At the same time, the height in the flow channel is adjustable. By adjusting the height of the flow channel, the adaptability of the flow box to the process is improved. Finally, the nanofiber slurry flows to the lip 5. After the adjustable upper lip plate mechanism 3 eliminates the liquid level fluctuation and controls the slurry flow trajectory, the uniformity quality of the nanofiber forming will be further improved.

Claims

1. A nanofiber forming device, characterized in that: It is a fully enclosed structure, including an extended flow channel pulp distributor, a flow channel, and an adjustable upper lip plate mechanism connected in sequence; the extended flow channel pulp distributor is a vertical single-channel type, and the cross-sectional area of ​​the flow channel perpendicular to the pulp flow direction gradually expands from a circular hole at the pulp inlet that is the same as the pulp pipe diameter to a rectangular area equal to that near the flow box, so as to ensure that the ultra-low concentration nanofiber slurry forms a stable isobaric distribution along the width direction; the flow channel inlet is rectangular, and the cross-sectional area further suddenly increases, and the height inside the flow channel is adjustable; the adjustable upper lip plate mechanism can adjust the displacement, and while achieving local fine-tuning of the lip opening height, it can also make forward and backward translation adjustments; the adjustable range of the flow channel height is 5mm-80mm.

2. The nanofiber forming device according to claim 1, characterized in that: The horizontal inclination angle of the vertical single flow channel of the extended flow channel slurry distributor is less than or equal to 60°.

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