Mixing kettle for preparing and supplying flash spinning solution

Abstract

The mixing kettle is used for preparing and supplying flash spinning liquid and comprises a mixing kettle body with an upper kettle opening and a lower kettle opening; the mixing jacket is used for controlling the temperature of the mixing kettle body; the hybrid driving device is used for providing hybrid power for the solute and the solvent in the mixing kettle body; the mixing kettle further comprises a solvent input structure, a solute input structure, a mixing pressure detection control structure, a mixing temperature detection structure and a mixing liquid level detection structure which are mounted on the mixing kettle body; and a solute outlet of the solute input structure, which is positioned in the mixing kettle body, is close to the longitudinal axis of the mixing kettle body. According to the mixing kettle for preparing and supplying the flash spinning solution, through corresponding structural design, the flash spinning solution can be prepared and supplied, the mixing kettle is used for production and manufacturing of a flash spinning process, and meanwhile, the mixing kettle can be matched with other structures and methods to achieve stable and continuous supply of the flash spinning solution.

Description

Technical Field

[0001] The invention relates to the field of flash spinning, in particular to a mixing kettle for preparing and supplying flash spinning solution. Background Art

[0002] Non-woven fabric, also known as non-woven fabric, is a fabric that does not require spinning and weaving. It is composed of oriented or random fibers. It is made by arranging textile short fibers or filaments in a directional or random manner to form a fiber web structure, and then reinforced by mechanical, thermal bonding or chemical methods.

[0003] Flash spinning, also known as instant spinning, is a special case of dry spinning using a flash spinning solution. It can be used to spin ultra-long fiber filaments and non-woven fabrics, and is therefore a technology and method for producing non-woven fabrics. Non-woven fabrics produced using this method are waterproof, moisture-proof, breathable, flexible, lightweight, non-combustible, easily decomposable, non-toxic, odorless, non-irritating, colorful, and recyclable. They are internationally recognized as environmentally friendly products and a new generation of environmentally friendly materials that protect the Earth's ecology. Due to the varying lengths and thicknesses (i.e., densities) of the fibers within, flash-spun non-woven fabrics can be produced with varying thickness, feel, and hardness by varying the processing equipment and raw materials. These products are suitable for use in various applications, including industrial (automotive interiors), chemical (printing substrates), healthcare (surgical gowns, protective clothing, disinfectant wraps, masks, diapers), apparel (shoemaking, leather), household (wallpaper, furniture fabrics, decorative materials, mattresses), and agriculture (reflective film).

[0004] For more information about existing flash spinning methods, as well as related systems, equipment, and methods for flash spinning to produce non-woven fabrics, please refer to Chinese invention patent applications such as CN115595675A, CN115852592A, and CN115976665A. Summary of the Invention

[0005] The problem solved by the present invention is to provide a mixing kettle for preparing and supplying flash spinning solution, so that the flash spinning solution can be prepared and supplied, and at the same time, it can be combined with other structures and methods to realize a stable and continuous flash spinning solution supply solution for the production and manufacturing of flash spinning process.

[0006] In order to solve the above problems, the mixing kettle for preparing and supplying flash spinning solution of the present invention includes: a mixing kettle body, having an upper kettle mouth and a lower kettle mouth; a mixing jacket, used to control the temperature of the mixing kettle body; a mixing drive device, used to provide hybrid power for the solute and solvent inside the mixing kettle body; the mixing kettle also includes a solvent input structure, a solute input structure, a mixing pressure detection control structure, a mixing temperature detection structure and a mixing liquid level detection structure installed in the mixing kettle body; the solute input structure is located at the solute outlet inside the mixing kettle body close to the longitudinal axis of the mixing kettle body.

[0007] Optionally, the distance between the solute outlet and the longitudinal axis is one tenth to one third of the radius of the cross section of the mixing kettle body.

[0008] Optionally, the height of the solute outlet is located at a position above two-thirds of the height of the mixing kettle body, and the solvent input structure is located at the solvent outlet of the mixing kettle body and extends to the bottom of the mixing kettle body.

[0009] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0010] The mixing kettle provided by the present invention is used for preparing and supplying flash spinning solution. It uses a mixing kettle body, a mixing jacket and a mixing drive device as the main structure, and is designed with a solvent input structure, a solute input structure, a mixing pressure detection control structure, a mixing temperature detection structure and a mixing liquid level detection structure. The solute input structure is arranged to be located inside the mixing kettle body, and the solute outlet is close to the longitudinal axis of the mixing kettle body, thereby providing a mixing kettle that can efficiently mix, accurately control and is easy to operate and maintain. The solute outlet is arranged close to the longitudinal axis of the mixing kettle body, which ensures that the solute is safely input during the mixing and dissolving process, and is subjected to a mixing drive from the inside to the outside and from the top to the bottom, better matches the action path of the mixing driving force, is more evenly distributed in the solvent, fully contacts and dissolves with the solvent, thereby enhancing the mixing effect and shortening the dissolution time. At the same time, it helps to reduce the risk of solute accumulation and adhesion on the edge or inner wall of the mixing kettle body, reduces agglomeration, further improves mixing uniformity, improves mixing efficiency and dissolution efficiency, and reduces energy consumption.

[0011] Furthermore, the distance between the solute outlet and the longitudinal axis is controlled to be one tenth to one third of the radius of the cross section of the mixing kettle body, so as to prevent the solute outlet from colliding with the mixing rotating shaft, and protect the mixing device and the solute outlet. In addition, since the solute output from the solute outlet has a certain initial velocity, viscosity and toughness, therefore, ensuring that the distance is within the corresponding range is beneficial for prompting the solute to be input into the solvent from the middle position of the solvent (i.e., near the longitudinal axis) as much as possible, solute can be more effectively contacted and mixed with the surrounding solvent, which helps the solute to be more evenly distributed in the solvent, thereby improving mixing efficiency and mixing uniformity. In addition, this design makes the position of the solute outlet have certain adjustability. By adjusting the distance, the design of the solute and solvent input pipeline can be adapted to a certain extent, the flexibility and applicability of the equipment can be improved, the maintenance of the equipment can be helped, the equipment maintenance cost can be reduced, and the reliability of the equipment can be improved.

[0012] For more information about the solutions, structures, methods, properties and advantages of the present invention, please refer to the subsequent contents of this specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of a first cross-sectional structure of a mixing kettle provided in one embodiment of the present invention;

[0014] Figure 2 for Figure 1 A second cross-sectional structural schematic diagram of the mixing kettle shown;

[0015] Figure 3 yes Figure 1 An enlarged schematic diagram of a portion of the structure of the mixing kettle shown;

[0016] Figure 4 1 is a front view schematic diagram of a solute outlet provided by one embodiment of the present invention;

[0017] Figure 5 is a bottom view schematic diagram of a solute outlet and corresponding structure provided by another embodiment of the present invention;

[0018] Figure 6 Schematic diagram of a hybrid rotating shaft and corresponding blades provided in another embodiment of the present invention.

[0019] 100 - Mixing kettle body; 100a - Upper portion; 100b - Middle portion; 100c - Lower portion; 101 - First mounting seat; 102 - Second mounting seat; 103 - Third mounting seat; 104 - Fourth mounting seat; 105 - Upper kettle edge; 106 - Lower kettle edge; 107 - Upper kettle opening; 108 - Lower kettle opening; 109 - Longitudinal axis (indicated by a dotted line); 110 - Solvent input structure; 111 - Solvent outlet; 112 - Solid pipe structure; 120 - Solute input structure; 121 - Vertical portion; 122 - Inclined portion; 123 - Solute outlet; 1231 - Sub-outlet; 130 - Mixing pressure detection and control structure; 140 - Mixing temperature liquid detection structure; 150 - Mixing baffle; 151 - Baffle fixing structure; 152 - Mixing temperature liquid fixing structure;

[0020] 200-mixing jacket; 201-heat exchange inlet; 202-heat exchange outlet; 203-temperature test structure; 204-fixed structure;

[0021] 300 - mixing drive device; 301 - mixing motor; 302 - mixing reducer; 303 - mixing frame; 304 - mixing head; 305 - mixing drive mounting base; 306 - mixing rotating shaft; 307 - mixing stirring blade; 308 - mixing stirring blade; 309 - connecting structure;

[0022] 400-external support; 401-side support structure; 402-longitudinal support structure; 403-pillar; 404-transverse reinforcement structure; 405-base structure;

[0023] H - the dividing line between the upper portion 100a and the middle portion 100b (indicated by a dotted line);

[0024] L - the dividing line between the middle portion 100b and the lower portion 100c (indicated by a dotted line);

[0025] D - distance between the solute outlet 123 and the longitudinal axis 109 (indicated by a dotted line);

[0026] R - cross-sectional radius of the mixing vessel 100 (indicated by a dotted line);

[0027] T-hollow arrow, indicating the outward orientation of the outlet plane of the solute outlet 123 (obliquely upward toward the longitudinal axis 109);

[0028] α-single curved corner between the vertical portion 121 and the inclined portion 122 of the solute input structure 120;

[0029] the angle between the outlet plane of the β-solute outlet 123 and the longitudinal axis 109 (indicated by a dashed line);

[0030] w - the gap width when the solute outlet 123 is a notched circular tube structure (indicated by a dotted line);

[0031] d—cross-sectional diameter of the mixing shaft 306 (shown by a dotted line). DETAILED DESCRIPTION

[0032] Flash spinning is difficult to implement because each step and detail presents numerous challenges that must be overcome. Detailed prior art documentation exists regarding the structure and methods of production equipment for preparing and supplying the flash spinning solution, as well as the structure and methods for continuously supplying the flash spinning solution for spinning.

[0033] An embodiment of the present invention provides a mixing kettle for preparing and supplying a flash spinning solution.

[0034] like Figures 1 to 3 As shown, the mixing kettle (not separately labeled) includes the main structures of the mixing kettle body 100, the mixing jacket 200, and the mixing drive device 300. It should be noted that in the various cross-sectional structural diagrams of the mixing kettle, only the mixing kettle body 100 and the mixing jacket 200 are shown in cross-section (hence the corresponding cross-sectional slashes), while most other structures are shown in non-cross-sectional schematic structures. This treatment is to better illustrate the various structures of the mixing kettle.

[0035] like Figure 3 As shown, the mixing kettle body 100 has an upper kettle opening 107 and a lower kettle opening 108. The upper kettle opening 107 is defined by the corresponding upper kettle edge 105, and the lower kettle opening 108 is defined by the corresponding lower kettle edge 106. Figure 1 and Figure 2The installation of the mixing drive device 300 and the sealing of the entire structure are shown. The design of the lower kettle mouth 108 takes into account the viscosity (thickness), temperature and other characteristics of the solution to ensure the required requirements for the solution output, while ensuring accurate measurement and stable delivery of the solution to ensure the continuity and stability of the entire production line. The upper kettle mouth 107 is the largest opening of the mixing kettle body 100 and is used for Figure 1 and Figure 2 The external structures such as the mixing drive device 300 are installed and extend into the mixing kettle body 100. The lower kettle port 108 is used as a solution outlet for further providing the solution to the next process (such as providing it to the subsequent transfer kettle related process).

[0036] Figure 3 The mixing vessel 100 is also shown as comprising an upper portion 100a, a middle portion 100b, and a lower portion 100c. The dividing line between the upper and middle portions 100a and 100b is indicated by a dashed line H, while the dividing line between the middle and lower portions 100b and 100c is indicated by a dashed line L. The upper and lower portions 100a and 100c are essentially symmetrical, spherical cap-like structures, but they have the aforementioned different openings and other different structures. The upper portion 100a includes a number of supporting structures, such as various detection and monitoring mechanisms. The middle portion 100b is cylindrical. The three portions, namely the upper, middle, and lower portions 100a and 100b, form a roughly capsule-shaped overall structure.

[0037] The mixing kettle body 100 can be made of corresponding alloy steel or stainless steel and other materials so as to be able to withstand corresponding pressure and temperature conditions, thereby providing a corresponding dissolving and mixing environment.

[0038] like Figures 1 to 2 The mixing jacket 200 is provided on the outside of the mixing kettle body 100 for controlling the temperature of the mixing kettle body 100. The mixing jacket 200 is a hollow structure, which is covered on the outer surface of the mixing kettle body 100. Figure 3 As can be seen, the mixing jacket 200 is attached to the majority of the outer surface of the middle portion 100b and the majority of the outer surface of the lower portion 100c of the mixing vessel 100. The shape of the mixing jacket 200 is determined by the outer shape of the mixing vessel 100, and thus, in this embodiment, exhibits a barrel-like structure. It should be noted that the shape and size of the mixing jacket 200 can be designed based on the amount of heat to be exchanged to ensure appropriate dissolution performance.

[0039] like Figure 1The mixing jacket 200 has a corresponding heat exchange inlet 201 and a heat exchange outlet 202. It can usually transfer heat or take away heat through the circulation of heat transfer media such as steam, water or oil. That is, the temperature control of the mixing kettle body 100 by the mixing jacket 200 can be achieved through corresponding steam circulation, water circulation or oil circulation, and can further be reflected in the mixing jacket 200 controlling the increase, decrease or maintenance of the internal temperature of the mixing kettle body 100. The mixing jacket 200 also has a corresponding temperature testing structure 203. Figure 1 In the cross-sectional structure shown, the temperature testing structure 203 is arranged at an upper position substantially symmetrical to the heat exchange outlet 202 so as to detect the temperature at a position farther from the heat exchange inlet 201, thereby being more conducive to accurate monitoring of the actual heating situation.

[0040] The main structure of the mixing jacket 200 can be made of a metal material with large heat exchange capacity and good thermal conductivity, and the efficiency and effect of temperature control can be adjusted by designing an appropriate heat exchange area.

[0041] like Figure 1 and Figure 2 The outer surface of the mixing jacket 200 also has a plurality of fixing structures 204, which are used to fix the mixing jacket 200 on the corresponding outer bracket 400. In this embodiment, the fixing structures 204 can be three, Figure 1 and Figure 2 A fixing structure 204 is shown respectively, and it can be seen that another fixing structure 204 is not shown.

[0042] like Figure 1 and Figure 2 The outer bracket 400 mentioned above is used to install the mixing kettle on a corresponding site, such as on the ground of a production workshop. The outer bracket 400 includes a side support structure 401, a longitudinal support structure 402, a pillar 403, a transverse reinforcement structure 404 and a base structure 405. The side support structure 401 is used to fix and support the mixing jacket 200 from the side of the mixing jacket 200, the longitudinal support structure 402 is used to fix and support the mixing jacket 200 from the fixed structure 204 of the mixing jacket 200, the pillar 403 provides the main supporting force, the transverse reinforcement structure 404 is connected to each pillar 403 near the bottom, and is used to make the entire outer bracket 400 more solid and stable, and the base structure 405 is used to fix the pillar 403 on the corresponding site (such as the workshop floor). In other embodiments, outer brackets with other structures can also be used to install the mixing kettle on the corresponding site.

[0043] like Figure 1 and Figure 2The mixing drive device 300 includes a mixing motor 301, a mixing reducer 302, a mixing frame 303, and a mixing head 304. The mixing frame 303 has structures such as a mixing transmission shaft (not shown) and a mixing coupling (not shown). Other structures of the mixing drive device 300 also include structures for mechanical sealing and auxiliary sealing. The mixing drive device 300 is used to provide hybrid power to the solute and solvent inside the mixing kettle body 100. When the corresponding power is stirring power, the mixing drive device 300 can stir the solvent and solute to achieve dissolution of the solute.

[0044] Usually, a solvent with a boiling point lower than that of the solute is selected for the preparation of flash spinning solution to ensure that the solvent cannot dissolve the solute at room temperature and pressure, but can dissolve the solute under pressurized heating. At the same time, it is ensured that the solute remains basically undecomposed for a long time when dissolved in the solvent. When the solute and the solvent are mixed, it is necessary to ensure that the mixing is heated to a temperature slightly higher than the boiling point of the solvent and is carried out under a relatively high pressure environment. This is also part of the design elements of the mixing kettle.

[0045] like Figure 1 The mixing drive device 300 includes a mixing rotating shaft 306 and two mixing stirring blades 307 and a mixing stirring pusher blade 308 mounted on the mixing rotating shaft 306. The mixing rotating shaft 306 is fixed to a shaft segment (not specifically labeled) extending from the mixer head 304 via a connecting structure 309. The connecting structure 309 can specifically connect the corresponding shaft segment and the mixing rotating shaft 306 by, for example, screwing. The arrangement of the connecting structure 309 at this position helps facilitate the installation of the entire mixing drive device 300 in the mixing kettle body 100. The first blade mounted from top to bottom on the mixing rotating shaft 306 is the mixing stirring blade 307, and the last blade is the mixing stirring pusher blade 308. The corresponding stirring structure of the mixing drive device 300 includes at least one mixing stirring blade 307 and at least one mixing stirring pusher blade 308, thus forming a multi-stage stirring structure. The mixing stirring blade 307 and the mixing stirring pusher blade 308 can be composed of two blades, three blades, four blades, or five blades. By combining two different blades, the mixing capability of the hybrid drive device 300 can be made more comprehensive.

[0046] Due to the presence of the mixing drive device 300, the polymer solute and organic solvent input into the mixing kettle body 100 can form axial flow (circulating flow in the vertical direction, which is more conducive to the dispersion effect) and radial flow (circulating flow in the horizontal direction, which is more conducive to the circulation effect itself) under the stirring of the various blades of the mixing drive device 300. The dispersion effect brought about by the stirring makes the polymer solute smaller and more fragmented at the microscopic level, but basically does not affect the degree of polymerization, so as to form a better contact effect with the solvent, so as to achieve complete dissolution by coordinating the corresponding pressure and temperature, and form an internal circulation effect. The circulation effect brought about by the stirring can ensure that more corresponding axial flow and radial flow are formed in the space of the mixing kettle, ensuring temperature balance and uniform composition. The dispersion effect and circulation effect jointly improve the heat exchange efficiency between the polymer solute and organic solvent and the external temperature control system (mixing jacket 200).

[0047] refer to Figure 1 and Figure 2 The hybrid drive device 300 further includes a hybrid drive mounting seat 305, which also serves as a sealed kettle cover for sealing the hybrid kettle body 100. The hybrid drive mounting seat 305 is sealed and mounted on the upper kettle edge 105, thereby forming a Figure 3 The sealing function of the upper kettle opening 107 is shown. Sealing condition is one of the important conditions for the use of the mixing kettle provided by the embodiment of the present invention. The embodiment of the present invention is equivalent to making the mixing drive mounting seat 305 a part of the mixing kettle body 100. Such a design can fully utilize the mutual cooperation of the two structures.

[0048] refer to Figures 1 to 3 The mixing kettle further includes a solvent input structure 110, a solute input structure 120, a mixing pressure detection and control structure 130, a mixing temperature detection structure, and a mixing liquid level detection structure, which are mounted on the mixing kettle body 100. The solvent input structure 110 is mounted on the upper portion 100a of the mixing kettle body 100 using a first mounting seat 101. At least a portion of the solvent input structure 110 is located inside the mixing kettle body 100, and this portion can be fixed to the inner wall of the mixing kettle body 100 via a fixed pipe structure 112. The solute input structure 120 is mounted on the upper portion 100a of the mixing kettle body 100 using a second mounting seat 102. The mixing pressure detection and control structure 130 is mounted on the upper portion 100a of the mixing kettle body 100 using a third mounting seat 103.

[0049] Figure 1It is also shown that, in a first cross-section of the mixing vessel 100 passing through the longitudinal axis 109, the solvent input structure 110 and the solute input structure 120 are located on either side of the longitudinal axis 109. This symmetrical design facilitates the input and mixing of the solvent and solute, and also contributes to the regularity of the overall structure. The solvent input structure 110 is used to continuously input a measured amount of solvent into the mixing vessel 100. The solute input structure 120 is used to continuously input a measured amount of solute into the mixing vessel 100. The solute may first be melted in other equipment and then input into the mixing vessel 100 through the solute input structure 120. The design of the solvent input structure 110 and the solute input structure 120 ensures that the mixing vessel 100 can be maintained under substantially the same conditions, and the corresponding mixing operation can be performed without opening the vessel to add the solvent and solute.

[0050] Figure 2 It is also shown that the mixed temperature detection structure and the mixed liquid level detection structure are combined into a mixed temperature liquid detection structure 140. The mixed temperature liquid detection structure 140 is used to detect the internal liquid temperature and liquid level at the same time, and its detection part is located inside the mixing kettle body 100. Figure 2 and Figure 3 As can be seen, the mixing temperature and liquid detection structure 140 is mounted on the upper portion 100a of the mixing kettle body 100 using the fourth mounting base 104. Since the solvent is an organic substance with a typically low boiling point and easy vaporization, accurate liquid level detection is necessary to provide real-time visibility of the liquid state within the kettle. Contact-type liquid detection devices are particularly effective in achieving this precise level detection. Liquid temperature is also crucial to solution formation. Therefore, locating the detection portion of the mixing temperature and liquid detection structure 140 within the mixing kettle body 100 ensures more accurate liquid temperature detection.

[0051] Figure 1 and Figure 2 It is also shown that there is at least one mixing baffle 150 inside the mixing kettle body 100. The mixing baffle 150 is fixed to the inside of the mixing kettle body 100 by a baffle fixing structure 151, and the number of mixing baffles 150 can be one or more. The mixing baffle 150 is used to prevent the formation of deeper vortices on the liquid surface during the stirring process, because deeper vortices are not conducive to the mixing of the solvent and the solute and the stability of the solution. At the same time, deeper vortices may also cause more inert gases to dissolve into the liquid, which is also not conducive to the subsequent spinning process of the spinning solution. At least a part of the mixed temperature liquid detection structure 140 is fixed on the mixing baffle 150. This structural design is conducive to protecting the mixed temperature liquid detection structure 140. The mixed temperature liquid detection structure 140 needs to be immersed in the liquid, and the stirred liquid will generate a corresponding force on the mixed temperature liquid detection structure 140, and the mixing baffle 150 can prevent the corresponding liquid force from damaging the mixed temperature liquid detection structure 140. In order to reinforce the mixed temperature liquid detection structure 140, Figure 2 It is also shown in the figure that the mixed temperature liquid detection structure 140 is fixed to the inner wall of the mixing kettle body 100 and the mixing baffle 150 by using the mixed temperature liquid fixing structure 152.

[0052] Although not shown in the figure, the mixing kettle may also include other structures and safety devices to ensure the safety of the equipment in the event of an unexpected abnormality. Examples include flammable and hazardous gas detectors, safety valve rupture discs, and alarm devices. Furthermore, these structures and safety devices can be connected to a unified control platform system along with the other aforementioned structures and devices, or they can be grouped and connected to multiple corresponding control and detection systems. Furthermore, the mixing kettle can be regularly inspected and maintained.

[0053] like Figure 1 and Figure 3 As shown, the solute input structure 120 includes a solute outlet 123 located inside the mixing tank body 100, and the solute outlet 123 is arranged close to the longitudinal axis 109 of the mixing tank body 100. Figure 1 and Figure 3 In FIG. 1 , the longitudinal axis 109 is shown as a longitudinal dashed line. Figure 1 and Figure 3 In the cross-section shown, it essentially bisects the mixing vessel 100 and the mixing axis 306. That is, the longitudinal axis 109 is the longitudinal center axis of the mixing vessel 100. The location of the solute outlet 123 affects the solute input location. If the solute outlet 123 is close to the inner wall of the mixing vessel 100, the solute, which is a polymer melt and has a high viscosity, may adhere to the inner wall and agglomerate, affecting the mixing and dissolution process. Therefore, the solute outlet 123 is positioned as far away from the inner wall of the mixing vessel 100 as possible, that is, close to the longitudinal axis 109 of the mixing vessel 100. This structure ensures the safe input of solutes during the mixing and dissolution process, and is driven by mixing from the inside out and from the top to the bottom, better matching the action path of the mixing driving force, more evenly distributed in the solvent, fully contacting and dissolving with the solvent, thereby enhancing the mixing effect and shortening the dissolution time. At the same time, it helps to reduce the risk of solute accumulation and adhesion on the edge or inner wall of the mixing kettle body 100, reduce agglomeration, and further improve mixing uniformity, improve mixing efficiency and dissolution efficiency, and reduce energy consumption.

[0054] The distance D between the solute outlet 123 and the longitudinal axis 109 (reference Figure 1 and Figure 3 ) is one tenth to one third of the cross-sectional radius R of the mixing kettle body 100. It should be noted that the cross-sectional area of ​​various kettle bodies generally refers to the cross-sectional area of ​​the main body thereof. In this embodiment, the cross-sectional area of ​​the mixing kettle body 100 is Figure 3The cross section of the middle portion 100b is shown. As mentioned above, the middle portion 100b is a cylindrical structure, so its cross section is a circular ring. It can be seen that the cross section radius R is the inner diameter of the circular ring.

[0055] To ensure that the solute outlet 123 is close to the longitudinal axis 109, the present embodiment sets the distance D to be within one-third of the cross-sectional radius R; to ensure that the solute outlet 123 does not collide with the mixing rotating shaft 306, so as to protect the mixing device and the solute outlet and prevent damage due to collision, the present embodiment controls the distance D to be at least one-tenth of the cross-sectional radius R. In addition, since the solute output from the solute outlet 123 has a certain initial velocity, viscosity and toughness, ensuring that the distance D is within the corresponding range is conducive to promoting the solute to be input into the solvent from the middle position of the solvent (i.e., near the longitudinal axis 109) as much as possible. The solute can more effectively contact and mix with the surrounding solvent, which helps the solute to be more evenly distributed in the solvent, thereby improving mixing efficiency and mixing uniformity. In addition, this design allows the position of the solute outlet to have a certain degree of adjustability. By adjusting the distance D, the design of the solute and solvent input pipelines can be adapted to a certain extent, improving the flexibility and applicability of the equipment, facilitating equipment maintenance, reducing equipment maintenance costs, and improving equipment reliability.

[0056] The solvent input structure 110 includes a solvent outlet 111 located within the mixing kettle body 100. The solvent outlet 111 extends to the lower portion 100c of the mixing kettle body 100. The solute outlet 123 is positioned at a height above two-thirds of the height of the mixing kettle body 100, ensuring that the solute is introduced into the solvent from above the liquid level. This prevents the solute from initially agglomerating at the solute outlet 123 due to the resistance of the liquid surface, and prevents the solute from sinking directly to the bottom of the mixing kettle body 100 due to gravity. This reduces the possibility of agglomeration and precipitation, improves the dispersion of the solute in the solvent, and enhances mixing efficiency and uniformity. When using the mixing kettle, the liquid level is typically maintained below two-thirds of the height of the mixing kettle body 100. After the solute is introduced from above, it forms a countercurrent with the solvent rising from the bottom, further improving mixing efficiency. This design allows the mixing kettle to adapt to different operating conditions, such as the introduction of solvent and solute in different batches, and the use of different mixing speeds, temperatures, and pressures, thereby enhancing the flexibility and applicability of the equipment. At the same time, the solute outlet is located at a higher position, which is convenient for detecting and controlling the solute input and mixing effect.

[0057] like Figure 1 and Figure 3 As shown, the solute input structure 120 allows the solute outlet 123 to be close to the longitudinal axis 109 of the mixing tank body 100 through the single bend structure of the pipeline. Figure 3It is shown that the single bending structure includes a vertical portion 121 and an inclined portion 122 (that is, the solute input structure 120 includes a vertical portion 121 and an inclined portion 122), and there is a single bending angle α between the vertical portion 121 and the inclined portion 122 (it should be noted that the single bending angle α is a concept of angle size, which is equivalent to the angle formed by the symmetry axes of the main parts of the vertical portion 121 and the inclined portion 122. Therefore, Figure 3 The single bending angle α is marked at the bend position formed by the smooth transition between the vertical portion 121 and the inclined portion 122. The single bending angle α is greater than or equal to 120 degrees and less than or equal to 165 degrees, thereby ensuring that the solute outlet 123 has an outlet plane that is obliquely upward toward the longitudinal axis 109 and ensuring that the structure is stable and reliable. The outlet plane of the solute outlet 123 is oriented in a direction perpendicular to the outlet plane and outward, such as Figure 3 Shown in hollow arrow T, hollow arrow T is obliquely upward toward longitudinal axis 109, that is, outlet plane obliquely upward toward longitudinal axis 109. According to the structure of solute outlet 123, the direction indicated by hollow arrow T is exactly the direction of the initial outflow velocity of solute (initial outflow velocity is the speed at which solute flows out of solute outlet 123 at an instant). It can be seen that the initial outflow velocity has a vertical upward component and a horizontal component. Although the final solute will enter the solvent at an oblique downward speed under the action of gravity, this initial vertical upward component and the horizontal component help the solute to be input into each part of the solvent in a more dispersed manner, so that the solute dispersion range is larger, and the distribution range particularly on the cross section of the solvent is larger, which helps the solute to be more evenly distributed in the solvent and can be dispersed into the solvent faster.

[0058] At the same time, in this embodiment, the angle β between the outlet plane of the solute outlet 123 and the longitudinal axis 109 is set to be between 15 degrees and 60 degrees. The single-bend structure allows the solute outlet 123 to be close to the longitudinal axis 109 of the mixing kettle body 100, which helps to evenly distribute the solute in the mixing kettle, so that the solute is injected from near the center of the mixing kettle body 100, which is conducive to the diffusion of the solute to the entire kettle body, reducing the situation where the local concentration is too high or too low. Compared with the pipeline design with multiple bends or complex structures, the single-bend structure is simpler, reduces manufacturing costs and installation difficulty, reduces eddy currents and turbulence in the pipeline, reduces pressure loss and fluid resistance in the pipeline, allows the solute to enter the mixing kettle more smoothly, improves the uniformity and efficiency of mixing, and improves the overall stability and reliability of the equipment. The outlet plane of the solute outlet 123 is tilted upward toward the longitudinal axis 109, so that the solute can enter the solvent at a certain angle, that is, enter the solvent in a more dispersed manner, further promoting the uniform mixing of the solute in the mixing kettle. At the same time, optimizing the angle β (between 15 degrees and 60 degrees) can further optimize the initial contact angle between the solute and the solvent, reduce the mixing time, and further improve the mixing efficiency and production efficiency.

[0059] The mixing kettle for preparing and supplying flash spinning solution provided in an embodiment of the present invention uses a mixing kettle body 100 as a main body, and uses a mixing jacket 200 and a mixing temperature detection structure (mixing temperature liquid detection structure 140) to control the temperature of the mixing kettle body 100 to help ensure that the solute and solvent are kept within the required temperature range during the mixing process. A mixing drive device 300 is used to provide a hybrid power, and a solvent input structure 110, a solute input structure 120, a mixing pressure detection control structure 130, a mixing temperature detection structure and a mixing liquid level detection structure (mixing The temperature liquid detection structure 140 is installed on the mixing kettle body 100 to monitor and control the mixing process, and the solute outlet 123 of the solute input structure 120 is close to the longitudinal axis 109 of the mixing kettle body 100 to prevent the solute from adhering to the side wall of the mixing kettle body 100, thereby helping the solute to disperse and dissolve in the mixing kettle body 100, reducing the phenomenon of local concentration being too high or too low, promoting the uniformity of the composition of the spinning solution, improving the mixing uniformity, and making the mixing process faster and more stable, reducing fluctuations in the production process, improving production efficiency, and enhancing safety. At the same time, the entire mixing kettle structure is reasonably designed, easy to operate and maintain, convenient for operators to carry out daily production operations and maintenance work, and reduce production costs.

[0060] like Figure 4 In another embodiment, the solute outlet 123 has a sieve structure rather than a whole hole. The sieve structure includes a plurality of sub-outlets 1231, and the shape of the sub-outlet 1231 is a regular hexagon (in other embodiments, it can also be other polygons, circles or ellipses). That is, the solute outlet 123 of this embodiment has an outlet structure similar to the surface of a shower head, or a hollow structure. The reasons for this design include: although the solute is basically in liquid form, its viscosity is relatively high. After being squeezed out of the solute outlet 123, it is still easy to agglomerate. Once agglomeration occurs, it is difficult to be dissolved; and the design Figure 4 The solute outlet 123 shown in the sieve structure allows the viscous solute to be further dispersed and squeezed into the interior of the mixing kettle 100 by the multiple sub-outlets 1231, similar to the state of "squeezing noodles", so that the solute is dispersed and squeezed into multiple thin strands or multiple streams and enters the solvent. Since the solute is divided into multiple thin strands or multiple streams and enters the solvent, it can prevent solute agglomeration and promote rapid solute dissolution. For more information on other structures, properties, and functions of this embodiment, please refer to the corresponding content of the previous embodiment.

[0061] In another embodiment, the bottom view schematic structure of the solute outlet 123 is as follows: Figure 5 As shown, it can be seen that the solute outlet 123 is a notched circular tube structure, and the notched circular tube structure itself is Figure 5 The solute outlet 123 and the inclined portion 122 are in the shape of a horizontally rotated English letter "C". Figure 5Separated by a dotted line (this dotted line is not marked), Figure 5 Only one section of the inclined portion 122 is shown. The lower surface of the notched circular tubular structure has a plurality of sub-outlets 1231, each of which is circular in shape. In other embodiments, the sub-outlets may also be polygonal or elliptical.

[0062] It should be noted that Figure 5 Shown is different from Figure 4 angle, Figure 5 This is a schematic diagram of the solute outlet 123 when viewed from above. This schematic diagram also shows the cross-sectional structure of the mixing rotating shaft 306. It can be seen that the sub-outlet 1231 is actually a circular hole opened downward to facilitate the corresponding solute to be injected downward into the solvent. Figure 5 It can be seen that, except for the notch portion, the sub-outlet 1231 of the solute outlet 123 surrounds the periphery of the mixing rotating shaft 306. At the same time, the notch width w of the notch circular tube structure is greater than or equal to the cross-sectional diameter d of the mixing rotating shaft 306 (at this time, the longitudinal axis 109 is perpendicular to the Figure 5 The center of the cross section of the mixing rotating shaft 306 coincides with the longitudinal axis 109), so that when the solute outlet 123 is installed, the mixing rotating shaft 306 can be installed to the corresponding notch. Figure 1 and Figure 2 The position shown, or in other words, ensures that the installation of the mixing rotating shaft 306 is not affected by the corresponding shape of the solute outlet 123. For more information about other structures, properties and functions of this embodiment, please refer to the corresponding content of the above embodiments.

[0063] The solute outlet 123 is designed as a notched circular tubular structure, wherein the notch width w is greater than or equal to the cross-sectional diameter d of the mixing rotating shaft 306. This design ensures that the mixing rotating shaft 306 can smoothly pass through the notched portion of the solute outlet during installation, thereby enabling the multiple sub-outlets 1231 to be arranged around the periphery of the mixing rotating shaft 306, thereby avoiding mutual interference between the solute outlet 123 and the mixing rotating shaft 306, and without requiring the mixing rotating shaft 306 to be changed. Furthermore, since the lower surface of the solute outlet 123 has multiple sub-outlets 1231, these sub-outlets 1231 are downwardly opened as circular holes (or other shapes, such as polygonal or elliptical), which facilitates the uniform and efficient dispersion, extrusion and injection of the solute into the solvent, thereby better preventing solute agglomeration and the like, and increasing the dispersion speed and uniformity of the solute in the solvent, thereby improving the mixing effect and mixing efficiency.

[0064] like Figure 6In another embodiment, the mixing and stirring blades 307 and the mixing and stirring pushing blades 308 on the mixing rotating shaft 306 are the same in number, two each, and are installed on the mixing rotating shaft 306 at intervals, that is, from top to bottom, they are the first mixing and stirring blade 307, the first mixing and stirring pushing blade 308, the second mixing and stirring blade 307, and the second mixing and stirring pushing blade 308. The first mixing and stirring blade 307 can be a folding blade, and the second mixing and stirring pushing blade 308 can be an anchor blade. The combined stirring of the two mixing and stirring blades 307 and the two mixing and stirring pushing blades 308 further ensures the corresponding breaking up and circulation effects, so as to more fully disperse the added polymer solute and organic solvent, ensure their full contact, and promote dissolution. Among them, when the mixing rotating shaft 306 rotates, the two mixing and stirring blades 307 mainly play the role of providing radial flow, while the two mixing and stirring pushing blades 308 mainly play the role of propulsive stirring. Compared with the two mixing and stirring blades 307, the two mixing and stirring blades 308 have a moderate distance from the kettle wall, which can prevent the solute from adhering to the wall and causing coking, control the axial flow rate of the solute and solvent circulating internally, control heat exchange, prevent local temperature from being too high, prevent the solvent and solute from stratifying up and down, and promote the temperature and heat to reach the desired balance.

[0065] More about Figure 6 For other structures, properties and functions of the illustrated embodiment, reference may be made to the corresponding contents of the aforementioned embodiments.

[0066] The embodiment of the present invention also provides a method for preparing and supplying a flash spinning solution by using a mixing kettle.

[0067] The mixing kettle can be the mixing kettle provided in the above embodiments, so you can refer to Figures 1 to 6 Corresponding content. As can be seen, the mixing kettle includes main structures such as a mixing kettle body 100, a mixing jacket 200, and a mixing drive device 300. The mixing kettle body 100 has an upper kettle port 107 and a lower kettle port 108; the mixing jacket 200 is used to control the temperature of the mixing kettle body 100; the mixing drive device 300 is used to provide hybrid power for the solute and solvent within the mixing kettle body 100; the mixing kettle also includes a solvent input structure 110, a solute input structure 120, a mixing pressure detection and control structure 130, a mixing temperature detection structure, and a mixing liquid level detection structure installed in the mixing kettle body 100. The solute input structure 120 is located at the solute outlet 123 inside the mixing kettle body 100, near the longitudinal axis 109 of the mixing kettle body 100. For more information on the structure, performance, and advantages of the mixing kettle, please refer to the corresponding content of the aforementioned embodiments.

[0068] The method of preparing and supplying flash spinning solution using a mixing kettle in this embodiment includes:

[0069] Mixing preparation step: using the mixing pressure detection control structure 130 to perform a vacuum operation on the interior of the mixing kettle body 100; after the vacuum operation is completed, continue to use the mixing pressure detection control structure 130 to fill the interior of the mixing kettle body 100 with inert gas to perform a pressure increase operation, and use the mixing jacket 200 to increase the temperature of the mixing kettle body 100; feeding and mixing step: using the mixing pressure detection control structure 130, the mixing jacket 200 and the mixing temperature detection structure to control the interior of the mixing kettle body 100 to reach a first mixing pressure and a first mixing temperature; start the mixing drive device 300 to provide hybrid power, and feed the solvent into the mixing kettle body 100 through the solvent input structure 110. The solvent is input into the solvent at a position near the longitudinal axis 109 inside the mixing kettle body 100 through the solute outlet 123 of the solute input structure 120 (since the solute outlet 123 of the solute input structure 120 is located inside the mixing kettle body 100 and is close to the longitudinal axis 109 of the mixing kettle body 100, this input method can be directly implemented using the solute outlet 123); a quantitative mixing step: after the input solvent and solute reach their respective predetermined amounts, the mixing drive device 300 continues to provide hybrid power for quantitative mixing; a supply step: after the quantitative mixing is performed for a predetermined time, the solution is supplied to the next production process through the lower kettle port 108 of the mixing kettle body 100.

[0070] The above method can utilize the corresponding mixing kettle to mix solutions. During the mixing and dissolving process, the solute can be safely and accurately input, and the solute can be subjected to the mixing driving force from the inside to the outside and from the top to the bottom, so as to better match the mixing driving force, be more evenly distributed in the solvent, fully contact and dissolve with the solvent, that is, ensure the completion of the dissolution process, have a good mixing effect, and accurately control the dissolution time. It also helps to reduce the risk of solute accumulation and adhesion on the edge or inner wall of the mixing kettle body 100, reduce agglomeration, and further improve mixing uniformity, improve mixing efficiency and dissolution efficiency, and reduce energy consumption.

[0071] In the above method, the steps are closely coordinated with each other, and the operation steps such as vacuuming, controlling the pressure increase with inert gas, and heating are used to create stable conditions for the mixing process. The solute is input at the center of the mixing kettle body 100 to ensure efficient and uniform mixing of the solvent and the solute. The process of inputting the solvent and the solute is reasonably arranged, and multiple steps are interconnected to fully ensure the dissolution process. The pressure, temperature and other conditions are controlled at all times throughout the method steps, which not only improves the mixing efficiency of the solution, but also ensures the stability of the solution. Finally, a uniform solution can be supplied to the next production process, ensuring the reliability and efficiency of production.

[0072] In the mixing preparation step, before using the mixed pressure detection control structure 130 to perform a vacuum operation on the inside of the mixing kettle body 100, first ensure that the mixing kettle body 100 has been sealed and has no leaks, and at the same time ensure that the mixed pressure detection control structure 130 is in good working condition, ensuring that it can accurately detect and control the pressure inside the mixing kettle body 100. Then start the vacuum operation, monitor the changes in the vacuum degree in real time, and adjust the vacuum speed as needed to achieve the required vacuum degree. Use the mixed pressure detection control structure 130 to monitor the pressure in the mixing kettle body 100 in real time, and make corresponding operational adjustments based on the set pressure range. If the pressure reaches the set range, a corresponding signal is sent, the maintenance state is adjusted, and the next operation is waited for. It should be noted that in the mixing preparation step, a partial heating operation can also be performed first to facilitate and accelerate the vacuum operation.

[0073] In the mixing preparation step, the process of using the mixing pressure detection control structure 130 to fill the mixing kettle body 100 with inert gas can include: providing inert gas, specifically nitrogen or argon, to ensure that each connection node of the inert gas supply structure is tight and leak-free; passing the inert gas into the mixing kettle body 100 through corresponding pipes and valves. During the inert gas supply process, the corresponding valve can be slowly opened first, and the inert gas can be gradually filled into the mixing kettle body 100. The gas flow rate is controlled by using the mixing pressure detection control structure 130 to ensure that the pressure gradually rises and that the mixing pressure detection control structure 130 monitors the pressure in the mixing kettle body 100 in real time; when the pressure reaches the preset value, the inert gas supply valve is closed to maintain the inside of the mixing kettle body 100 within the corresponding stable pressure range.

[0074] During the mixing preparation step, while the mixing vessel 100 is being pressurized by injecting inert gas, the mixing jacket 200 can be used to simultaneously perform a temperature increase operation. This temperature increase operation includes activating the mixing jacket 200's corresponding power and heat source supply devices (e.g., a steam boiler burner, a hot oil pump motor, etc., not shown), controlling the flow of a heating medium (e.g., hot oil, steam, hot water, etc., not shown) through appropriate valves and connectors into the heat exchange inlet 201 of the mixing jacket 200. After the heating medium fills the mixing jacket 200, it returns to the power and heat source supply devices through the heat exchange outlet 202 of the mixing jacket 200, forming a cycle, thereby allowing the corresponding heating medium to continuously control the temperature of the mixing vessel 100. The flow rate and temperature of the heating medium are adjusted to control the temperature increase rate of the mixing vessel 100. During this process, the temperature test structure 203 of the mixing jacket 200 and the mixed temperature detection structure (mixed temperature liquid detection structure 140) can be used simultaneously to detect the internal temperature of the mixing kettle body 100 and the heating temperature of the mixing jacket 200, so as to adjust the flow rate and temperature of the heating medium as needed to maintain the desired heating curve. When the interior of the mixing kettle body 100 reaches the desired temperature, the temperature control system is adjusted to maintain a stable temperature for a period of time. At the same time, the mixed pressure detection control structure 130 is used to ensure that the pressure and temperature inside the mixing kettle body 100 are within the preset range. The corresponding preset ranges can be the first mixed pressure and the first mixed temperature.

[0075] As mentioned above, the preset ranges for temperature and pressure in the mixing preparation step are also to adjust the temperature and pressure to the first mixing pressure and the first mixing temperature. However, at the beginning of the feeding and mixing step, it is necessary to ensure that this condition is achieved. Therefore, the coordination of the mixing pressure detection control structure 130, the mixing jacket 200 and the mixing temperature detection structure is further utilized to control the interior of the mixing kettle body 100 to reach the first mixing pressure and the first mixing temperature. Therefore, when the pressure inside the mixing kettle body 100 is lower than the set first mixing pressure value, the mixing pressure detection control structure 130 increases the pressure. When the pressure is higher than the set first mixing pressure value, the mixing pressure detection control structure 130 reduces the pressure. When the pressure reaches the corresponding requirement, it is maintained. Through such a feedback adjustment mechanism, it is ensured that the pressure inside the mixing kettle body 100 is always maintained near the set first mixing pressure value. Similarly, when the temperature inside the mixing kettle body 100 is lower than the set first mixing temperature value, the mixing temperature detection structure will feed this information back to the control system. After receiving the signal, the control system will start or increase the temperature control function of the mixing jacket 200 to control the temperature of the mixing kettle body 100. When the temperature is lower than the set first mixing temperature value, heating is performed. When the temperature reaches the set first mixing temperature value, heating is stopped or maintained in a manner to maintain temperature stability (so that heat dissipation and heat supply are kept in dynamic balance). On the contrary, when the temperature is higher than the set first mixing temperature value, the control system will control the mixing jacket 200 to stop heating to appropriately cool the mixing kettle body 100 so that the temperature returns to the set first mixing temperature value. Through such a feedback regulation mechanism, it is ensured that the temperature inside the mixing kettle body 100 is always maintained near the set first mixing temperature value. In addition, before pressure regulation and temperature adjustment, in order to improve the accuracy of control, the sensors such as the mixing pressure detection control structure 130 and the mixing temperature detection structure can be correspondingly inspected, calibrated and maintained. Through the cooperation of the mixing pressure detection control structure 130 , the mixing jacket 200 and the mixing temperature detection structure, the interior of the mixing kettle body 100 is effectively controlled to reach the set first mixing pressure and first mixing temperature values.

[0076] The solvent input structure 110 is a channel for inputting the solvent into the mixing kettle body 100. The pre-prepared solvent is accurately input into the mixing kettle body 100 through the solvent input structure 110. Specifically, the solvent can be transported into the mixing kettle body 100 through the pipeline by opening the corresponding valve (not shown) of the solvent input structure 110.

[0077] The solute input structure 120 is a channel for inputting solute into the mixing kettle body 100. Through the solute input structure 120, the solute is accurately input into the mixing kettle body 100 near the longitudinal axis 109, thereby achieving the desired mixing effect. Specifically, the solute can be transported to the solute outlet 123 through a pipeline by opening the corresponding valve (not shown) of the solute input structure 120. According to the requirements of the mixing process, the input amount and input speed of the solute are controlled to ensure that the solute can be evenly dispersed in the solvent. During the process of inputting the solute, the operating parameters of the mixing drive device 300, such as the rotational speed or the stirring mode and direction, can be adjusted to promote the mixing of the solute and the solvent.

[0078] During the feeding and mixing step, the mixing drive device 300 is responsible for providing the necessary mixing power, driving the liquid within the mixing kettle 100 to achieve uniform mixing of the solvent and solute. Furthermore, parameters such as the operating speed and stirring time of the mixing drive device 300 can be controlled in real time based on the mixing requirements. Polymer solutes are molten—both melts and liquids—but are non-Newtonian fluids. Under shear, their viscosity changes with changes in shear rate or shear strain rate. The shear force is generated by the mixing and stirring force of the mixing drive device 300. Therefore, the rotational speed of the mixing drive device 300 influences the dissolution of the polymer solute in multiple ways.

[0079] During the mixing process, the mixing conditions within the mixing vessel 100 are closely monitored to understand the mixing state. This can be achieved through monitoring parameters such as temperature, pressure, and viscosity. If uneven mixing or abnormalities are detected, the operating parameters of the mixing drive device 300 or the input of solvent and solute are promptly adjusted. By activating the mixing drive device 300 and utilizing the coordinated operation of the solvent input structure 110 and the solute input structure 120, effective mixing of the solvent and solute is achieved, ensuring stable and reliable mixing.

[0080] Once the input solvent and solute have reached their respective predetermined amounts, the mixing drive 300 precisely controls the mixing speed, duration, and intensity to ensure that the solvent and solute are fully and evenly mixed. Appropriate temperature and pressure are maintained during the mixing process to achieve quantitative mixing. The predetermined amounts of solvent and solute are determined before the mixing vessel 100 begins inputting the solvent and solute. The sum of the predetermined amounts of solvent and solute is the total predetermined amount of liquid, which determines the liquid level within the mixing vessel 100.

[0081] The dissolution of a polymer solute, particularly high-density polyethylene (HDPE), in a corresponding organic solvent is a complex and multi-stage process. This process typically involves a swelling phase caused by solvent penetration and a subsequent polymer dispersion phase. During the solvent penetration phase, solvent molecules gradually penetrate between the HDPE molecular chains, causing the polymer to swell. During this phase, small organic solvent molecules continue to penetrate the polymer interior, causing significant swelling. The degree of swelling is determined by both the polymer's molecular structure and the solvent's physicochemical properties. Following the swelling phase, the polymer dispersion phase begins, during which the polymer macromolecules begin to gradually disentangle and separate, ultimately becoming uniformly dispersed in the solvent as polymer molecules, forming a stable polymer solution. When preparing a supercritical solution such as a flash spinning dope, ensuring the complete dissolution of the HDPE in the solvent is crucial. The dissolution process must be carried out at relatively high temperature and pressure to promote effective solvent penetration and sufficient swelling and dispersion of the polymer. Sufficient time is required during the quantitative mixing step to ensure full dispersion of the polymer chains, thereby producing a uniform solution. Generally speaking, the time required for the quantitative mixing step will exceed the time required for the adding mixing step. This is to ensure the sufficient dissolution of the high-density polyethylene and the uniformity of the solution.

[0082] Combined with reference Figures 1 to 3 After the quantitative mixing step, the solvent and solute have reached the desired degree of mixed dissolution. At this point, the uniformly mixed solution is transferred to the next production process using the lower kettle port 108 of the mixing kettle body 100. The lower kettle port 108 is typically connected to a corresponding structure that facilitates control of the outflow of the solution, such as a valve and a pipe interface. After the mixing process is completed, the valve (not shown) corresponding to the lower kettle port 108 is controlled, and the combined effects of pressure, mechanical power, and gravity are simultaneously utilized to allow the uniformly mixed solution to flow smoothly out of the mixing kettle body 100 and be supplied to the next production equipment (production process).

[0083] In the embodiment of the present invention, during the feeding and mixing step, the solute is introduced into the solvent. Therefore, the solvent is always introduced into the mixing vessel 100 first, followed by the solute. Furthermore, this embodiment employs a phased and batched approach to introduce the solvent and solute to their respective predetermined amounts (typically different, with the volume of solvent introduced typically being multiple times the volume of solute). Temperature and pressure are gradually controlled during the mixing process. This process is used to prepare the flash spinning solution, ensuring efficient mixing and a uniform and stable solution.

[0084] Specifically, in this embodiment, under the conditions of a first mixing temperature and a first mixing pressure, a predetermined amount of solvent is first input through the solvent input structure 110, and then a predetermined amount of solute is input through the solute input structure 120. Then, the interior of the mixing kettle 100 is controlled to reach a second mixing temperature and a second mixing pressure by the cooperation of the mixing pressure detection and control structure 130, the mixing jacket 200, and the mixing temperature detection structure. Then, a predetermined amount of solvent is input through the solvent input structure 110, and then a predetermined amount of solute is input through the solute input structure 120. Thereafter, the interior of the mixing kettle 100 is controlled to reach a third mixing temperature and a third mixing pressure by the cooperation of the mixing pressure detection and control structure 130, the mixing jacket 200, and the mixing temperature detection structure. Then, a predetermined amount of solvent is input through the solvent input structure 110, and finally, a predetermined amount of solute is input through the solute input structure 120. In this case, the first, second, and third mixing temperatures gradually decrease, and the first, second, and third mixing pressures gradually increase.

[0085] In the above process, first, under the conditions of the first mixing temperature and the first mixing pressure, a predetermined amount of one-third of the solvent is input through the solvent input structure 110. This is to establish a preliminary solvent environment in the mixing kettle body 100. Then, through the solute input structure 120, a predetermined amount of one-third of the solute is input from a position close to the middle of the solvent liquid surface so that the solute is safely input. At this time, the solute begins to contact with the solvent and preliminary mixing occurs. Then, the interior of the mixing kettle body 100 is controlled to reach the second mixing temperature and the second mixing pressure by utilizing the coordination of the mixing pressure detection control structure 130, the mixing jacket 200 and the mixing temperature detection structure. This step adjusts the mixing conditions to be suitable for further input of solvent and solute and further promotes their mixing. Because, during the second input of solvent and solute, the inert gas in the mixing kettle body 100 will be compressed and the pressure will naturally increase. In order to facilitate dissolution, this embodiment utilizes this phenomenon of natural pressure increase to increase the corresponding pressure. During this process, the mixed pressure detection and control structure 130 can be used to actively and simultaneously increase or timely adjust (to prevent excessive pressure increase) the corresponding pressure to control the pressure to the desired range, i.e., the second mixed pressure. At the same time, the corresponding temperature needs to be lowered to the second mixed temperature. This is because flash spinning solution is a dissolution under supercritical conditions, which requires both relatively high temperature and relatively high pressure conditions. The suitable temperature and pressure are usually only within a small range. When the pressure increases, the temperature needs to be lowered accordingly to ensure that the appropriate dissolution conditions are achieved. At the same time, lowering the temperature not only saves energy, but also prevents the danger of the solution with a relatively higher solubility and larger volume at this time, thereby making the entire dissolution process safer. Afterwards, that is, after the second batch of solutes is dissolved, the interior of the mixing kettle body 100 is controlled to reach the third mixed temperature and the third mixed pressure. At this time, the temperature is further reduced and the pressure is further increased. The reasons are basically the same as those mentioned above (making full use of the natural increase in pressure and lowering the temperature to reduce energy consumption and risks, etc.). Under the appropriate temperature and pressure conditions, the final third of solvent is introduced through solvent input structure 110, and finally, the final third of solute is introduced through solute input structure 120. At this point, all solvents and solutes have been introduced according to the predetermined proportions and conditions. The gradual increase in pressure and decrease in temperature also achieve a dynamic equilibrium, ensuring a smooth mixing and dissolution process.

[0086] If solute and solvent are directly input at the same time, it may happen that each of them exists in its own region. At this time, stirring is carried out again. Since the corresponding solute viscosity is high, it is easy to aggregate and stick together into agglomerates. Once aggregated and stuck together into agglomerates, it is difficult to achieve dissolution, and the corresponding production process may not be achieved. Therefore, it is necessary to pay attention to the input method of solute and solvent to prevent adverse situations such as solute aggregation and sticking together from occurring. The above-mentioned process of inputting solvent and solute in batches in stages can prevent the phenomenon of agglomeration and the like caused by inputting a large amount of polymer at one time and affecting the dissolution rate, and is more conducive to dissolution as a whole. At the same time, each stage of inputting solvent and solute in batches in stages, respectively controlling the temperature and pressure in the mixing kettle body 100, can more effectively promote the uniform distribution of solute in the solvent, help avoid the situation where the local concentration is too high or too low, thereby further improving the mixing efficiency. Finally, inputting solvent and solute in stages also helps to control mixing conditions, reduce safety risks, and prevent the occurrence of dangerous situations such as explosion or fire caused by local concentration being too high or viscosity being too large.

[0087] In this embodiment, the first mixing temperature and the first mixing pressure can be controlled to be within the ranges of 250±3°C and 8±0.5 MPa, respectively; the second mixing temperature and the second mixing pressure can be controlled to be within the ranges of 240±3°C and 13±0.5 MPa, respectively; and the third mixing temperature and the third mixing pressure can be controlled to be within the ranges of 200-220°C and 15-20 MPa, respectively. The corresponding conditions are set to ensure that the solvent and solute are dissolved under safe conditions and within the range that the mixing kettle 100 can withstand.

[0088] Under the above conditions, a relatively high temperature and a relatively low pressure are first used to promote the initial mixing and dissolution of the solvent and the solute, and then the pressure is increased and the temperature is lowered to maintain the corresponding dissolution efficiency. Finally, the temperature is lowered to a wider lower range, and the pressure is further increased to a relatively high range to ensure further dissolution of the solvent and the solute. This process not only takes into account the dissolution efficiency, but also fully considers the safety and the bearing capacity of the equipment, as well as the self-adaptation of the gas pressure and temperature (as the liquid increases at any time, the gas in the kettle is compressed, and the pressure usually increases automatically, while the newly added liquid usually has a relatively low temperature, which can easily cause the overall temperature of the liquid to drop slightly), taking into account the safety and stability of the equipment.

[0089] In this embodiment, the hybrid power provided by the hybrid drive device 300 is a mixing and stirring force; the first mixing and stirring speed at the first mixing temperature and the first mixing pressure is the initial speed; the second mixing and stirring speed at the second mixing temperature and the second mixing pressure is 0.7 to 0.9 times the initial speed; the third mixing and stirring speed at the third mixing temperature and the third mixing pressure is 0.5 to 0.7 times the initial speed; the quantitative stirring speed during the quantitative mixing step is 0.5 to 0.7 times the initial speed, while the temperature and pressure are kept substantially constant; and the supply stirring speed during the supply step is 1.1 to 1.2 times the initial speed, while the temperature is kept constant and the pressure is increased. The initial speed may be 20 to 150 revolutions per minute (r / min).

[0090] In the above-mentioned stirring conditions, at the first mixing temperature and the first mixing pressure, the mixing stirring speed is set to the initial speed, and the solvent and solute begin to contact and preliminarily mix. This initial speed is the basis for subsequent speed adjustment. When the mixing conditions become the second mixing temperature and the second mixing pressure, as the temperature and pressure change, especially the change of the liquid volume in the kettle, the speed is reduced in time, and the stirring speed is adjusted to 0.7 to 0.9 times the initial speed. At this time, the viscosity of the liquid may increase, and the stirring speed is reduced accordingly to avoid excessive stirring causing the degree of polymerization of the polymer to decrease (cracking or damage), etc. At the third mixing temperature and the third mixing pressure, the stirring speed is further reduced to 0.5 to 0.7 times the initial speed, which helps to reduce the damage of shear force to the solvent and solute and maintain the mixing effect. The solution concentration remains basically unchanged at this stage, but the liquid volume (mass) is large, and it takes longer time and milder conditions to achieve a specific mixing effect. By adjusting the stirring speed according to the changes in mixing temperature and pressure, the uniform mixing of solvent and solute can be more effectively achieved.

[0091] In the quantitative mixing step, the stirring speed is maintained at 0.5 to 0.7 times the initial speed, while the temperature and pressure remain essentially unchanged. The speed adjustment at this stage helps ensure that the mixed material can maintain a uniform and stable mixed state when the material is quantitatively added. In the supply step, the stirring speed is increased to 1.1 to 1.2 times the initial speed, while the temperature remains unchanged, but the pressure is gradually increased. The speed adjustment purpose at this stage includes simultaneously providing power for the solution to be output outwards, ensuring that the solution can be smoothly output from the mixing device, and the condition for increasing the pressure is also for outputting the solution outwards. The increased pressure needs to be ensured to be within a moderate range to prevent the solution from changing. The increased pressure is one of the power sources for the solution output, and the stirring at 1.1 to 1.2 times the initial speed provides another solution output power. This increased pressure is a dynamic increased pressure, which is used to ensure that the solution enters the next production process at an appropriate terminal pressure condition, and is also used to ensure that the solution maintains a basically stable speed when it is output from the mixing kettle body 100 (that is, the corresponding pressure can be dynamically adjusted based on the speed at which the mixing kettle body 100 outputs the solution to keep the speed as consistent as possible, or the pressure can be adjusted as needed to adjust the output speed). It can be seen that when outputting the solution, there is a coordinated effect of the two forces. Reasonable speed adjustment can ensure solution preparation and supply, reduce equipment wear and failure rate, and improve efficiency.

[0092] It should be noted that after the first supply step, the preparatory mixing step (i.e., the next round of adding and mixing, quantitative mixing, and supply steps) is no longer performed. In other words, the corresponding preparatory mixing step is omitted at this point because the mixing vessel is already fully prepared for adding and mixing, eliminating the need for re-preparation. Omitting these steps speeds up the entire preparation process, enabling rapid and continuous mixing of the solution and shortening the preparation and supply process.

[0093] refer to Figures 1 to 3 In this embodiment, the solute outlet 123 is located at a height greater than two-thirds of the height of the mixing vessel 100, and the solvent inlet 111 of the solvent inlet structure 110 extends from the lower portion 100c of the mixing vessel 100. In this manner, the method enables the inlet of solutes from a height greater than two-thirds of the height of the mixing vessel 100 and the inlet of solvents from the lower portion 100c of the mixing vessel 100. For details, reference may be made to the corresponding contents of the aforementioned embodiments.

[0094] In this embodiment, the solute outlet 123 has an outlet plane that is angled upward toward the longitudinal axis 109. The solute outlet 123 allows the solute to be introduced into the solvent at an initial, upward outflow velocity. Due to the structural characteristics of the solute outlet 123, the direction indicated by the hollow arrow T is the direction of the initial outflow velocity. Because the solute is introduced into the solvent at this angle and initial outflow velocity, it typically enters the solvent in a more dispersed manner, making it less susceptible to undesirable phenomena such as agglomeration or flocculation.

[0095] refer to Figure 1 and Figure 2 In this embodiment, the mixing drive device 300 has a mixing rotating shaft 306 and at least one mixing stirring blade 307 and at least one mixing stirring pushing blade 308 installed on the mixing rotating shaft 306; the first blade installed from top to bottom on the mixing rotating shaft 306 is the mixing stirring blade 307, and the last blade is the mixing stirring pushing blade 308; in the feeding mixing step and the quantitative mixing step, the mixing rotating shaft 306, the mixing stirring blade 307 and the mixing stirring pushing blade 308 are used to provide a composite hybrid power; in the supply step, the mixing rotating shaft 306, the mixing stirring blade 307 and the mixing stirring pushing blade 308 are used to provide a composite output power to the solution.

[0096] During the preparation of the flash spinning solution, if the temperature or pressure fails to reach the appropriate conditions, such as the temperature is too high or the pressure is too low, the solvent may vaporize (vaporization usually occurs when the temperature exceeds the boiling point of the solvent or the pressure is lower than the saturated vapor pressure of the solvent). At the same time, under inappropriate conditions, the polymer solute may not be able to disperse and dissolve, such as aggregation, degradation, cross-linking or flocculation (i.e., precipitation). Therefore, starting from the preparation step, the corresponding temperature and pressure conditions are controlled, and from the feeding step, the flow rate, flow velocity, temperature, pressure, liquid level, viscosity, stirring speed and other parameters of the solvent and solute are monitored to control the dissolution rate and degree. In the quantitative mixing step, the relevant parameters of the mixing process, including temperature, pressure, liquid level and viscosity, are monitored to prepare the corresponding solution and provide it to the next production process.

[0097] In this embodiment, in addition to temperature and pressure conditions, the stirring speed and stirring time at each step are adjusted and controlled to ensure sufficient stability during the dissolution process. Generally, excessively high stirring speeds can cause bubbles to form in the liquid, affecting the uniformity of dissolution and even causing local overheating or equipment wear. Excessively low stirring speeds can slow the dissolution process, hindering uniform dispersion of the solute in the solvent. In the initial stages of dissolution, a slightly higher stirring speed is selected to promote rapid dispersion of the solute. As the dissolution process progresses, the stirring speed is gradually reduced to better maintain a stable solution state and avoid unnecessary energy consumption and equipment wear. Excessively short stirring times can result in incomplete solute dissolution, affecting the uniformity and stability of the final solution. Excessively long stirring times can increase production costs and potentially cause undesirable conditions, such as decomposition of polymer solutes. To determine the stirring time, it is necessary to monitor the viscosity changes, temperature, and pressure of the solution during the dissolution process in real time to ensure the stirring time required to achieve a stable dissolution state. The stirring time for each step is adjusted according to these parameters to ensure the stability and efficiency of the dissolution process. When adjusting the stirring speed and stirring time, coordinate with the adjustment of temperature and pressure, and control the stirring parameters in real time to keep the dissolution process in the desired state.

[0098] Combined with reference Figure 4 In other embodiments, the solute outlet 123 may have a sieve structure, which includes multiple sub-outlets 1231. The sub-outlets 1231 are polygonal, circular, or elliptical in shape. In this case, the method can disperse the solute into the solvent through the multiple sub-outlets 1231 to further prevent adverse phenomena such as solute aggregation or flocculation.

[0099] Combined with reference Figure 5 In other embodiments, the solute outlet 123 is a notched circular tubular structure, and the lower surface of the notched circular tubular structure has a plurality of sub-outlets 1231, and the shape of the sub-outlets 1231 is polygonal, circular or elliptical; the notch width w of the notched circular tubular structure is greater than or equal to the cross-sectional diameter d of the mixing rotating shaft 306; This method can be achieved by Figure 5 The multiple sub-outlets 1231 are arranged to disperse the solute into the solvent at positions partially surrounding the mixing rotation axis 306 and close to the longitudinal axis 109 , so as to further prevent the solute from agglomerating or flocculating.

[0100] Combined with reference Figure 6In other embodiments, the mixing and stirring blades 307 and the mixing and stirring blades 308 are identical in number, two each, and are installed on the mixing rotation shaft 306 with spacing therebetween, namely, from top to bottom, the first mixing and stirring blade 307, the first mixing and stirring blade 308, the second mixing and stirring blade 307, and the second mixing and stirring blade 308. Specifically, the first mixing and stirring blade 307 can be a folding blade, and the second mixing and stirring blade 308 can be an anchor blade. The dual blades more fully disperse the added polymer solute and organic solvent, ensuring sufficient contact between them and promoting dissolution.

[0101] In other embodiments, during the material adding and mixing step, under the conditions of a first mixing temperature and a first mixing pressure, one-half of the predetermined amount of solvent can be first input through the solvent input structure 110, and then one-half of the predetermined amount of solute can be input through the solute input structure 120; then, the interior of the mixing kettle body 100 is controlled to reach a second mixing temperature and a second mixing pressure by utilizing the coordination of the mixing pressure detection control structure 130, the mixing jacket 200 and the mixing temperature detection structure, and then one-quarter of the predetermined amount of solvent is input through the solvent input structure 110, and then one-quarter of the predetermined amount of solute is input through the solute input structure 120; thereafter, the interior of the mixing kettle body 100 is controlled to reach a third mixing temperature and a third mixing pressure by utilizing the coordination of the mixing pressure detection control structure 130, the mixing jacket 200 and the mixing temperature detection structure, and one-quarter of the predetermined amount of solvent is input through the solvent input structure 110, and finally, one-quarter of the predetermined amount of solute is input through the solute input structure 120. Compared to the embodiment in which one-third of the solvent and solute are added at a time, adding one-half of the solvent and solute directly first can fully utilize the space inside the mixing kettle 100 in the early stage (at this time, the polymer is relatively less likely to agglomerate, etc., while the subsequent solution concentration increases, the solute is relatively less likely to dissolve and is relatively more likely to agglomerate). This allows for the addition of a relatively large amount of mixed solutes first, thereby further improving the dissolution effect. For more information about the method of this embodiment, please refer to the corresponding content of the previous embodiment.

[0102] In order to simplify the content, this specification has largely avoided duplication in the composition, properties, functions, principles, effects and advantages of the same or similar structures and method steps between the various embodiments. Therefore, the composition, properties, functions, principles, effects and advantages of the different embodiments of this specification can be referenced and supplemented by each other.

[0103] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. The technical solutions described in the embodiments may be modified, or some or all of the technical features therein may be replaced by equivalents. The technical features designed in different implementation modes may be combined with each other as long as they do not conflict with each other, and the corresponding technical solutions shall not deviate from the scope of protection required by the present invention. All other embodiments obtained based on the embodiments of the present invention without creative work shall fall within the scope of protection of the present invention.

Claims

1. A mixing kettle for preparing and supplying flash spinning solution, characterized in that: include: A mixing kettle body (100) having an upper kettle opening (107) and a lower kettle opening (108); A mixing jacket (200) for controlling the temperature of the mixing kettle (100); A mixing drive device (300) for providing hybrid power to the solute and solvent inside the mixing kettle (100); The invention also includes a solvent input structure (110), a solute input structure (120), a mixing pressure detection control structure (130), a mixing temperature detection structure, and a mixing liquid level detection structure installed in the mixing kettle body (100); the solute input structure (120) is located at a solute outlet (123) inside the mixing kettle body (100) close to the longitudinal axis (109) of the mixing kettle body (100).

2. The mixing kettle according to claim 1, wherein The distance (D) between the solute outlet (123) and the longitudinal axis (109) is one tenth to one third of the cross-sectional radius (R) of the mixing kettle body (100).

3. The mixing kettle according to claim 1, wherein The height of the solute outlet (123) is located at a position above two-thirds of the height of the mixing kettle body (100), and the solvent input structure (110) is located at the solvent outlet (111) of the mixing kettle body (100) and extends to the bottom (100c) of the mixing kettle body (100).

4. The mixing kettle according to claim 1, 2 or 3, wherein: The solute outlet (123) has an outlet plane that faces obliquely upward toward the longitudinal axis (109).

5. The mixing kettle according to claim 4, characterized in that The solute input structure (120) enables the solute outlet (123) to be close to the longitudinal axis (109) of the mixing kettle body (100) through the single-bend structure of the pipeline, and the single-bend structure has a single-bend angle (α) in the angle range of 120 degrees to 165 degrees; the outlet plane of the solute outlet (123) has an angle (β) with the longitudinal axis (109) in the angle range of 15 degrees to 60 degrees.

6. The mixing kettle according to claim 1, 2 or 3, characterized in that: The solute outlet (123) has a sieve structure, and the sieve structure includes a plurality of sub-outlets (1231). The shape of the sub-outlets (1231) is polygonal, circular or elliptical.

7. The mixing kettle according to claim 1, wherein The mixing drive device (300) comprises a mixing rotating shaft (306) and at least one mixing stirring blade (307) and at least one mixing stirring blade (308) mounted on the mixing rotating shaft (306); the first blade mounted on the mixing rotating shaft (306) from top to bottom is the mixing stirring blade (307), and the last blade is the mixing stirring blade (308).

8. The mixing kettle according to claim 7, characterized in that The mixing and stirring blades (307) and the mixing and stirring blades (308) are of the same number and are installed on the mixing rotating shaft (306) at intervals.

9. The mixing kettle according to claim 7, wherein The solute outlet (123) is a notched circular tubular structure, and the lower surface of the notched circular tubular structure has multiple sub-outlets (1231), and the shape of the sub-outlets is polygonal, circular or elliptical; the notch width (w) of the notched circular tubular structure is greater than or equal to the cross-sectional diameter (r) of the mixing rotating shaft (306).

10. The mixing kettle according to claim 1, wherein The mixing drive device (300) comprises a mixing drive mounting seat (305), the mixing drive mounting seat (305) also serving as a sealing kettle cover for sealing the mixing kettle body (100); the mixing temperature detection structure and the mixing liquid level detection structure are a combined function of a mixing temperature and liquid detection structure (140); the mixing kettle body (100) has at least one mixing baffle (150) inside, and at least a portion of the mixing temperature and liquid detection structure (140) is fixed on the mixing baffle (150).

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