Aromatic fiber continuous spinning device and control method

Abstract

The present application relates to a production process of para-aramid fiber, in particular to a continuous spinning device and control method of para-aramid fiber. The device comprises: a feeding assembly for providing polymer material; a mixing assembly for mixing the material provided by the feeding assembly; a kneader for mixing the material with concentrated sulfuric acid to form a spinning dope; a spinneret for spinning the spinning dope to form a nascent fiber; a washing machine for washing the nascent fiber; a dryer for drying the washed nascent fiber to form a finished fiber; and a controller for controlling the running state of the spinning device in combination with the control method. The present application improves the feeding method of aramid spinning process, realizes continuous and stable spinning through the combination of different viscosity raw materials, reduces the viscosity requirement of the spinning process on the polymer raw material, and realizes the decoupling of the polymerization process and the spinning process in the existing para-aramid production process.

Description

Technical Field

[0001] The invention relates to a para-aramid fiber production process, in particular to a para-aramid fiber continuous spinning device and a control method. Background Art

[0002] Para-aramid fiber, also known as poly(p-phenylene terephthalamide) fiber (hereinafter referred to as PPTA fiber), has excellent physical and chemical properties such as high strength, high modulus, high temperature resistance, acid and alkali resistance, and light weight. It is widely used in military fields such as aerospace and civilian fields. It is also widely used as a reinforcing material in composite materials.

[0003] The production process of para-aramid fiber mainly includes polymerization process and spinning process. The polymerization process mainly produces PPTA resin required for spinning. The spinning process dissolves PPTA resin in concentrated sulfuric acid to form PPTA / concentrated sulfuric acid liquid crystal slurry at high temperature (80-90°C). Under the action of relatively high shear force, the liquid crystal slurry is sprayed out at high speed in a dry spray manner. After water washing, drying and subsequent heat treatment, para-aramid fiber is obtained.

[0004] The strength of para-aramid fiber is the most important parameter for its product performance. Different industrial applications are determined by the fiber's strength. For example, the strength of para-aramid fiber in the civilian sector is between 20-23 cN / dtex, while military applications generally require a strength above 23 cN / dtex. Furthermore, the consistency of para-aramid fiber strength is also a crucial parameter. Specifically, the smaller the fluctuation in para-aramid fiber strength within a given length range, the better.

[0005] The strength of para-aramid fibers is primarily influenced by polymer resin viscosity (or polymer molecular weight) and the spinning environment. Polymer resin viscosity is the primary factor, serving as a macroscopic indicator of polymer molecular weight. As relative molecular weight increases, fiber strength and modulus generally increase. This is because higher molecular weight polymer chains are longer and intermolecular interactions are stronger, thereby improving the fiber's mechanical properties. The spinning environment is a complex process, encompassing factors such as the spinneret draw ratio (SSF) and heat treatment. The SSF influences the fiber's tensile flow orientation, which in turn affects its strength. A higher SSF indicates a stronger tensile flow orientation and higher fiber strength. Heat treatment temperature, tension, and time also influence the fiber's modulus and strength.

[0006] Currently, the continuous production of para-aramid fibers with consistent strength remains an industry challenge. This is due to the uncontrollable viscosity of the polymer resin, while the spinning environment is relatively easy to control. While the polymerization process is simple in principle, numerous factors influence PPTA polymerization due to the high monomer activity and rapid reaction speed, as well as the gradual decrease in PPTA solubility in solvents with increasing molecular weight. Key factors include raw material purity, solvent system, moisture content, monomer ratio, monomer concentration, acid absorbent, reaction temperature and time, feed method, agitation, and shearing.

[0007] The existing para-aramid fiber production process is as follows: PPTA resin is produced through a polymerization process. After testing, the PPTA resin is stored in a tank area. The tank area transports the PPTA resin to the spinning workshop for spinning. The finished fibers are then tested for strength. The finished fibers are classified according to the test results. Warehouse management selects products that meet the strength requirements for shipment based on sales orders. The existing production process has the following problems:

[0008] 1. The problem of finished fiber inventory backlog. Due to the different viscosities of the polymer inventory materials, the finished fiber strengths produced after entering the spinning process are different, and the corresponding sales only require fibers within a specified strength range. This will lead to a large amount of finished fiber inventory, and it is necessary to wait for orders with different strength requirements to digest the inventory, thereby increasing production costs.

[0009] 2. The problem of polymer material inventory backlog. If polymers with corresponding viscosity are selected for spinning according to order requirements, para-aramid fibers that meet the strength requirements can be produced. However, as mentioned earlier, due to the uncertainty of the polymerization reaction, the viscosity of the polymer produced is also uncertain. If only polymers that meet the viscosity requirements are selected for spinning, a large amount of polymers with other viscosities will be accumulated, which will also lead to an increase in production costs. Summary of the Invention

[0010] The object of the present invention is to provide a para-aramid fiber continuous spinning device and a control method to solve the problems raised in the above background technology.

[0011] The present invention provides a para-aramid fiber continuous spinning device, comprising:

[0012] Feeding assembly, used to provide polymer material that meets the spinning viscosity and quantity requirements,

[0013] A mixing component is used to mix the materials provided by the feeding component.

[0014] The kneader mixes the materials provided by the mixing component with concentrated sulfuric acid to form a spinning solution.

[0015] The spinneret spins the spinning solution to form nascent fibers.

[0016] Washing machine, for washing the nascent fibers.

[0017] The dryer dries the washed nascent fibers to form finished fibers.

[0018] The controller controls the operation state of the spinning device in combination with the control method.

[0019] The feeding component includes multiple feeding loops, which can provide polymer materials with different viscosities. The output end of the feeding loop is connected to the input end of the mixing component, and the mixing component mixes the polymer materials with different viscosities input by the feeding loop.

[0020] As a further embodiment of the present invention, a continuous spinning device for para-aramid fibers further includes a first pipe and a second pipe, wherein one end of the first pipe and the second pipe are respectively connected to the end of the feed loop, and the other end thereof is connected to the mixing assembly, and a control valve is provided between the feed loop and the first pipe and the second pipe for pipe selection.

[0021] As a further embodiment of the present invention, the feed circuit comprises:

[0022] Silos, used to store polymer materials of different viscosities,

[0023] A loss-in-weight scale is installed at the silo outlet to measure the output material flow.

[0024] A pneumatic conveying device is connected to the loss-in-weight scale outlet and is used to convey polymer materials. The outlet of the pneumatic conveying device is connected to the first pipeline through a first valve, and the outlet of the pneumatic conveying device is connected to the second pipeline through a second valve.

[0025] As a further embodiment of the present invention, the mixing assembly includes a cyclone, a second feed pipe and a nozzle, a first feed pipe is provided on the outside of the cyclone, the first feed pipe is connected to the first pipeline, the nozzle is installed in the cyclone, and the nozzle is connected to the second pipeline through the second feed pipe.

[0026] As a further embodiment of the present invention, the upper part of the cyclone is a straight cylinder, a cover plate is provided on the top of the straight cylinder, the outer side of the straight cylinder is connected to the first feed pipe along the tangential direction, the bottom of the straight cylinder is connected to a conical barrel, the small end of the conical barrel faces downward, the lower end of the conical barrel is connected to the discharge port, and the discharge port is connected to the feed port of the kneader.

[0027] As a further embodiment of the present invention, an exhaust hole is further provided on the cover plate, and an air filter is provided at the outlet of the exhaust hole.

[0028] As a further embodiment of the present invention, the nozzle includes a nozzle body, which is a conical structure. A plurality of air channels are arranged in the nozzle body, the air channel inlets are arranged on the conical bottom surface of the nozzle body, and the air channel outlets are arranged on the side of the nozzle body.

[0029] As a further embodiment of the present invention, the air channel is a spiral air channel, and a plurality of the air channels are arranged in a circular array along the central axis of the nozzle.

[0030] As a further embodiment of the present invention, the nozzle also includes a flow guide, which is a conical structure. The bottom surface of the flow guide is installed at the center of the conical bottom surface of the nozzle body, and is used to disperse the airflow in the second feed pipe into multiple air channels.

[0031] As a further embodiment of the present invention, the nozzle is rotatably mounted at the end of the second feeding pipe.

[0032] As a further embodiment of the present invention, the mixing assembly also includes a bearing, which is installed on the outside of the end of the second feed pipe. A mounting portion is also provided above the bottom surface of the nozzle body, and the mounting portion is sleeved on the outer circle of the bearing and fixed by a flange.

[0033] As a further embodiment of the present invention, a disturbing body is provided on the inner wall of the conical barrel.

[0034] The present invention also provides a control method using the above-mentioned para-aramid continuous spinning device, the steps of which include:

[0035] Step S1: Obtain the viscosity data and inventory data of all polymer materials in the silo, sort them by viscosity and store them in the dictionary D[k i ], where k i is the viscosity of the material in the silo, D[k i ] is the viscosity k i The stock value of the material;

[0036] Step S2, obtaining the target fiber yield and target fiber strength requirements required by the spinning process, and obtaining the target viscosity η and unit target mass M of the polymer material based on the target fiber yield and target fiber strength requirements;

[0037] Step S3, determine the dictionary D[k i ] whether there is k i =η, and the stock value D[k i ]>0, if the judgment result is true, go to step S5, otherwise go to step S4;

[0038] Step S4, combining the polymer materials in the existing silo in proportion and then unloading them;

[0039] Step S5, cutting.

[0040] The method for combining the polymer materials in step S4 is as follows:

[0041] Step S41, obtain the dictionary D[k i ] The viscosity is greater than the target viscosity η and the first viscosity η1 with the largest inventory value, and the silo with viscosity η1 is selected as the first silo;

[0042] Step S42, obtain the dictionary D[k i ] The viscosity is less than the target viscosity η and the first viscosity η2 with the largest inventory value, and the silo with viscosity η2 is selected as the second silo;

[0043] Step S43, calculating the unit discharge volume of the first silo and the unit discharge volume of the second silo respectively by the following formula:

[0044] m1=(η-η2)M / (η1-η2);

[0045] m2=(η1-η)M / (η1-η2);

[0046] in,

[0047] m1 is the unit discharge capacity of the first silo;

[0048] m2 is the unit discharge volume of the second silo.

[0049] As a further embodiment of the present invention, a control method for continuous spinning of para-aramid fiber is provided, wherein the unit discharge amount m1 of the first silo calculated in step S43 is compared with the unit discharge amount m2 of the second silo, and the polymer material corresponding to the maximum value of the two enters the mixer through the first feed pipe 217, and the polymer material corresponding to the minimum value enters the mixer through the second feed pipe.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] The present invention improves the feeding method of the aramid spinning process, achieving continuous and stable spinning by combining raw materials of varying viscosities. This reduces the viscosity requirement of the spinning process for the polymerized raw materials and decouples the polymerization and spinning processes in existing para-aramid production processes. To achieve these technical effects, the present invention also provides a mixing device and method for users to mix materials of varying viscosities. This improves mixing efficiency and quality, ensuring that the strength of the spun product meets requirements, while also reducing inventory and lowering costs at the polymerization backend. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is a schematic structural diagram of a para-aramid fiber continuous spinning device according to the present invention;

[0053] Figure 2 for Figure 1 A cross-sectional view of the mixing assembly;

[0054] Figure 3 for Figure 2 Enlarged view of the middle part B;

[0055] Figure 4 for Figure 2 Structural view of the middle cyclone;

[0056] Figure 5 for Figure 2 Structural view of the middle nozzle;

[0057] Figure 6 for Figure 2 Sectional view of AA in the middle;

[0058] Figure 7 This is a flow chart of a method for controlling continuous spinning of para-aramid fibers according to the present invention;

[0059] Figure 8 for Figure 7 The control flow of step S4;

[0060] The meaning of each number in the figure is:

[0061] Feeding component 1, mixing component 2, kneading machine 3, spinning machine 4, washing machine 5, drying machine 6,

[0062] Feeding circuit 10, first pipeline 11, second pipeline 12, silo 101, loss-in-weight scale 102, pneumatic conveying device 103, first valve 104, second valve 105,

[0063] Cyclone 21, second feed pipe 22, nozzle 23, bearing 24, flange 25, air filter 26,

[0064] Conical barrel 211, straight cylinder 212, discharge port 213, cover plate 214, exhaust hole 215, mounting hole 216, first feed pipe 217, disturbing body 218,

[0065] The nozzle body 231 , the mounting portion 232 , the flow guide 233 , and the air channel 234 . DETAILED DESCRIPTION

[0066] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0067] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0068] In the existing para-aramid production process, the strength of the spun product is uncertain, and the classification of the spun product is determined after quality inspection of the finished fiber. Therefore, the existing continuous production of para-aramid is not truly continuous production. For example, if a customer requires a batch of fibers with a strength of 21 cN / dtex, the existing production process is a polymerization and spinning process, and quality inspectors select fibers that meet the required strength and provide them to the customer. Due to the uncertainty of the polymerization process, the viscosity of the polymer material is directly related to the strength of the finished fiber, so the strength of the spun product will also fluctuate. Therefore, the existing technical solutions cannot continuously produce spun fibers of a certain strength. Example 1

[0069] like Figure 1 As shown, the present invention provides a para-aramid fiber continuous spinning device, comprising:

[0070] Feeding component 1 is used to provide polymer material that meets the spinning viscosity and quantity requirements.

[0071] The mixing component 2 mixes the materials provided by the feeding component 1.

[0072] The kneader 3 mixes the material provided by the mixing component 2 with concentrated sulfuric acid to form a spinning solution.

[0073] The spinneret 4 spins the spinning solution to form nascent fibers.

[0074] Washing machine 5, washing the nascent fibers,

[0075] Dryer 6, dries the washed nascent fibers to form finished fibers.

[0076] The controller controls the operation state of the spinning device in combination with the control method.

[0077] The feeding assembly 1 comprises a plurality of feeding circuits 10 which can provide polymer materials of different viscosities, the output end of the feeding circuit 10 is connected with the input end of the mixing assembly 2, and the mixing assembly 2 mixes the polymer materials of different viscosities input by the feeding circuit 10.

[0078] To solve the problem that the existing technology cannot continuously produce para-aramid fibers with a certain strength, the embodiment provides a para-aramid continuous spinning device, which decouples the existing polymerization process and spinning process, and stores polymer materials produced by the polymerization process in different feeding circuits 10 according to different viscosities, wherein the viscosity of the polymer material can be determined by an online viscosity detection device at the end of the polymerization process, thereby improving the detection efficiency of the artificial.

[0079] In the technical scheme provided by the embodiment, the controller can control the feeding assembly 1 to provide polymer materials required for spinning, including a single polymer material meeting the viscosity requirement or a combined polymer material meeting the viscosity requirement. When there is no material meeting the requirement in the inventory polymer material, the controller can combine the existing materials according to the viscosity, and the combined material cannot be directly put into the kneader 3 for mixing with concentrated sulfuric acid because the viscosities of the combined material and the concentrated sulfuric acid are different, which can cause stratification and affect the spinning quality. Therefore, the mixing assembly 2 is needed to fully mix the combined material before it is put into the kneader 3. Embodiment 2

[0080] As shown in Figure 1 the embodiment, in addition to all the contents of the previous embodiment, the embodiment further provides a feeding circuit 10, which comprises: a material bin 101 for storing polymer materials of different viscosities, a loss-on-ignition scale 102 installed at the outlet of the material bin 101 for metering the output material flow, and a pneumatic conveying device 103 connected with the outlet of the loss-on-ignition scale 102 for conveying the polymer material.

[0081] The feeding assembly 1 further comprises a first pipe 11 and a second pipe 12, one end of each of the first pipe 11 and the second pipe 12 is connected with the end of the feeding circuit 10, and the other end is connected with the mixing assembly 2, and a control valve is arranged between the feeding circuit 10 and the first pipe 11 and the second pipe 12 for pipe selection.

[0082] The outlet of the pneumatic conveying device 103 is connected with the first pipe 11 through a first valve 104, and the outlet of the pneumatic conveying device 103 is connected with the second pipe 12 through a second valve 105.

[0083] In this embodiment, the controller can control the operation of the first valve 104 or the second valve 105 in different feed loops 10 to achieve connection with the first pipeline 11 or the second pipeline 12. In this embodiment, the first valve 104 or the second valve 105 is interlocked to ensure that the silo 101 in each feed loop 10 can only be connected to one of the first pipeline 11 or the second pipeline 12. By controlling the valve combination in each feed loop 10, it is possible to combine materials of different viscosities, that is, to select two materials of different viscosities and control their ratio. Example 3

[0084] like Figure 2-5 As shown, in addition to including all the contents of the previous embodiment, this embodiment also provides a mixing component 2, which includes a cyclone 21, a second feed pipe 22 and a nozzle 23. A first feed pipe 217 is provided on the outside of the cyclone 21, and the first feed pipe 217 is connected to the first pipeline 11. The nozzle 23 is installed in the cyclone 21, and the nozzle 23 is connected to the second pipeline 12 through the second feed pipe 22.

[0085] Furthermore, the upper portion of the cyclone 21 is a straight cylinder 212, with a cover plate 214 disposed on the top of the straight cylinder 212. The outer side of the straight cylinder 212 is tangentially connected to the first feed pipe 217. The bottom of the straight cylinder 212 is connected to a conical barrel 211, with the small end of the conical barrel 211 facing downward. The lower end of the conical barrel 211 is connected to a discharge port 213, which is connected to the feed port of the kneader 3. The cover plate 214 is also provided with an exhaust hole 215, and the outlet of the exhaust hole 215 is provided with an air filter 26. Preferably, the inner wall of the conical barrel 211 is provided with a turbulent body 218.

[0086] Furthermore, the nozzle 23 includes a nozzle body 231 having a conical structure. A plurality of air channels 234 are provided within the nozzle body 231. The inlets of the air channels 234 are provided on the conical bottom surface of the nozzle body 231, and the outlets are provided on the side surfaces of the nozzle body 231. Preferably, the air channels 234 are spiral air channels, and the plurality of air channels 234 are arranged in a circular array along the central axis of the nozzle 23.

[0087] Furthermore, the nozzle 23 also includes a flow guide 233 , which is a conical structure. The bottom surface of the flow guide 233 is installed at the center of the conical bottom surface of the nozzle body 231 , and is used to disperse the airflow in the second feed pipe 22 into multiple air channels 234 .

[0088] Further, the spray head 23 is rotatably installed at the end of the second feeding pipe 22. Preferably, the mixing assembly 2 further comprises a bearing 24 installed outside the end of the second feeding pipe 22, and the bottom surface of the spray head body 231 is further provided with a mounting portion 232 sleeved on the outer circle of the bearing 24 and fixed by a flange 25.

[0089] In the embodiment, a mixing mode is provided, in which two materials with different viscosities enter the mixing assembly through different channels. The combination of the two materials with different viscosities is carried out in a certain proportion. When the flow rates of the two materials are different, the material with a larger flow rate enters the cyclone drum 21 through the first feeding pipe 217, and the material with a smaller flow rate enters the spray head 23 through the second feeding pipe 22.

[0090] One material enters the cyclone drum 21 under the driving of high-pressure gas flow and spirally descends along the inner wall of the conical barrel 211, and the other material enters the cyclone drum 21 through the spiral air channel 234 of the spray head 23. The rotation direction of the material entering the cyclone drum 21 through the first feeding pipe 217 is opposite to that of the material entering the cyclone drum 21 through the spray head 23. As shown in Figure 6 the top view, the material entering the cyclone drum 21 through the first feeding pipe 217 rotates counterclockwise, and the spiral direction of the air channel 234 is clockwise. Therefore, when the two materials contact in the drum, the mixing effect is better due to the opposite directions. Further, since the inner wall is provided with a spoiler 218, when the material spirally descending along the inner wall passes through the spoiler 218, the spoiler 218 changes the flow direction of the material and throws it to the position close to the spray head 23, so that the two materials are mixed in the air, improving the mixing effect.

[0091] In the embodiment, the spray head 23 is further rotatably installed at the lower end of the second feeding pipe 22, and the rotation of the spray head 23 is realized by the spiral gas flow in the air channel 234. The advantage of this design is that the rotating spray head 23 is conducive to the mixing of the two materials, and avoids the uneven mixing caused by the long-term uneven flow of the materials in the multiple air channels 234 in the spray head 23. Embodiment 4

[0092] As shown in Figure 7 the top view, the material entering the cyclone drum 21 through the first feeding pipe 217 rotates counterclockwise, and the spiral direction of the air channel 234 is clockwise. Therefore, when the two materials contact in the drum, the mixing effect is better due to the opposite directions. Further, since the inner wall is provided with a spoiler 218, when the material spirally descending along the inner wall passes through the spoiler 218, the spoiler 218 changes the flow direction of the material and throws it to the position close to the spray head 23, so that the two materials are mixed in the air, improving the mixing effect.

[0093] Step S1: Obtain the viscosity data and inventory data of the polymer materials in all hoppers, and store them in a dictionary D[k i ] in order of viscosity size, where k i is the viscosity value of the material in the hopper, and D[k i ] is the inventory value of the material with viscosity k i ;

[0094] Step S2, obtaining the target fiber yield and the strength requirement of the target fiber required by the spinning process, and obtaining the target viscosity η and the unit target mass M of the polymer material according to the target fiber yield and the strength requirement of the target fiber;

[0095] Step S3, judging whether k i =η exists in the dictionary D[k i ], and the inventory value D[k i ]>0, if the judgment result is true, executing step S5, otherwise executing step S4;

[0096] Step S4, proportionally combining the polymer materials in the existing silo and then discharging;

[0097] Step S5, discharging.

[0098] As shown in the figure, the method of combining the polymer materials in step S4 is as follows: Figure 8

[0099] Step S41, obtaining the first viscosity η1 with the largest inventory value in the dictionary D[k i ] whose viscosity is greater than the target viscosity η, and selecting the silo with the viscosity η1 as the first silo;

[0100] Step S42, obtaining the first viscosity η2 with the largest inventory value in the dictionary D[k i ] whose viscosity is less than the target viscosity η, and selecting the silo with the viscosity η2 as the second silo;

[0101] Step S43, calculating the unit discharge amount of the first silo and the unit discharge amount of the second silo through the following formulas respectively:

[0102] m1=(η-η2)M / (η1-η2);

[0103] m2=(η1-η)M / (η1-η2);

[0104] wherein,

[0105] m1 is the unit discharge amount of the first silo;

[0106] m2 is the unit discharge amount of the second silo.

[0107] As a further embodiment of the present application, a control method for continuous spinning of para-aramid fiber, the unit discharge amount m1 of the first silo and the unit discharge amount m2 of the second silo calculated in step S43 are compared, the polymer material corresponding to the maximum value of the two is introduced into the mixer through the first feeding pipe 217, and the polymer material corresponding to the minimum value is introduced into the mixer through the second feeding pipe (22).

[0108] ​This embodiment provides a method for mixing polymer materials. The advantage of this method is that it maximizes the use of the material with the largest inventory among the current polymer materials, reduces the extrusion of the polymer materials and reduces production costs. At the same time, the selection of the polymer material with the largest inventory is conducive to the stability of spinning quality.

[0109] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A control method for continuous spinning of para-aramid fiber, characterized in that The following steps are involved: Step S1: Obtain the viscosity data and inventory data of all polymer materials in the silo, sort them by viscosity and store them in the dictionary D[k i ], where k i is the viscosity of the material in the silo, D[k i ] is the viscosity k i The stock value of the material; Step S2, obtaining the target fiber yield and target fiber strength requirements required by the spinning process, and obtaining the target viscosity η and unit target mass M of the polymer material based on the target fiber yield and target fiber strength requirements; Step S3, determine the dictionary D[k i ] whether there is k i =η, and the stock value D[k i ]>0, if the judgment result is true, go to step S5, otherwise go to step S4; Step S4, combining the polymer materials in the existing silo in proportion and then unloading them, the combining method includes: Step S41, obtain the dictionary D[k i ] The viscosity is greater than the target viscosity η and the first viscosity η1 with the largest inventory value, and the silo with viscosity η1 is selected as the first silo; Step S42, obtain the dictionary D[k i ] The viscosity is less than the target viscosity η and the first viscosity η2 with the largest inventory value, and the silo with viscosity η2 is selected as the second silo; Step S43, calculating the unit discharge volume of the first silo and the unit discharge volume of the second silo respectively by the following formula: m1=(η-η2)M / (η1-η2); m2=(η1-η)M / (η1-η2); Among them, m1 is the unit discharge capacity of the first silo; m2 is the unit discharge capacity of the second silo; Step S5, blanking; The above method uses a para-aramid fiber continuous spinning device, comprising: The feeding component (1) is used to provide polymer material that meets the spinning viscosity and quantity requirements, A mixing component (2) is used to mix the materials provided by the feeding component (1). The kneader (3) mixes the material provided by the mixing component (2) with concentrated sulfuric acid to form a spinning solution. The spinneret (4) spins the spinning solution to form nascent fibers. The washing machine (5) washes the raw fibers. The dryer (6) dries the washed nascent fibers to form finished fibers. The controller controls the operation state of the spinning device in combination with the control method. The feeding component (1) comprises a plurality of feeding loops (10), and the plurality of feeding loops (10) can provide polymer materials with different viscosities. The output end of the feeding loop (10) is connected to the input end of the mixing component (2), and the mixing component (2) mixes the polymer materials with different viscosities input from the feeding loop (10).

2. The control method for continuous spinning of para-aramid according to claim 1, characterized in that: The unit discharge amount m1 of the first silo calculated in step S43 is compared with the unit discharge amount m2 of the second silo, and the polymer material corresponding to the maximum value between the two enters the mixer through the first feed pipe 217, and the polymer material corresponding to the minimum value enters the mixer through the second feed pipe (22).

3. The control method for continuous spinning of para-aramid according to claim 2, characterized in that: The para-aramid fiber continuous spinning device further comprises a first pipeline (11) and a second pipeline (12), one end of the first pipeline (11) and the second pipeline (12) are respectively connected to the end of the feeding loop (10), and the other end thereof is connected to the mixing assembly (2), and a control valve is provided between the feeding loop (10) and the first pipeline (11) and the second pipeline (12) for pipeline selection.

4. The control method for continuous spinning of para-aramid according to claim 3, characterized in that: The feed circuit (10) comprises: The silo (101) is used to store polymer materials of different viscosities. A loss-in-weight scale (102) is installed at the outlet of the silo (101) to measure the output material flow rate. A pneumatic conveying device (103) is connected to the outlet of the loss-in-weight scale (102) and is used to convey polymer materials. The outlet of the pneumatic conveying device (103) is connected to the first pipeline (11) through a first valve (104), and the outlet of the pneumatic conveying device (103) is connected to the second pipeline (12) through a second valve (105).

5. The control method for continuous spinning of para-aramid according to claim 4, characterized in that: The mixing assembly (2) includes a cyclone (21), a second feed pipe (22) and a nozzle (23), A first feed pipe (217) is provided outside the cyclone (21), and the first feed pipe (217) is connected to the first pipeline (11). The nozzle (23) is installed in the cyclone (21), and the nozzle (23) is connected to the second pipeline (12) through the second feed pipe (22).

6. The control method for continuous spinning of para-aramid according to claim 5, characterized in that: The upper part of the cyclone cylinder (21) is a straight cylinder (212), and a cover plate (214) is provided on the top of the straight cylinder (212). The outer side of the straight cylinder (212) is connected to the first feed pipe (217) along the tangential direction. The bottom of the straight cylinder (212) is connected to the conical barrel (211), the small end of the conical barrel (211) faces downward, and the lower end of the conical barrel (211) is connected to the discharge port (213), and the discharge port (213) is connected to the feed port of the kneader (3).

7. The control method for continuous spinning of para-aramid according to claim 6, characterized in that: The cover plate (214) is further provided with an exhaust hole (215), and an outlet of the exhaust hole (215) is provided with an air filter (26).

8. The control method for continuous spinning of para-aramid according to claim 7, characterized in that: The nozzle (23) comprises a nozzle body (231), the nozzle body (231) is a conical structure, a plurality of air channels (234) are arranged in the nozzle body (231), the inlet of the air channel (234) is arranged on the conical bottom surface of the nozzle body (231), and the outlet thereof is arranged on the side of the nozzle body (231).

9. The control method for continuous spinning of para-aramid according to claim 8, characterized in that: The air passage (234) is a spiral air passage, and a plurality of the air passages (234) are arranged in a circular array along the central axis of the nozzle (23).

10. The control method for continuous spinning of para-aramid according to claim 9, characterized in that: The nozzle (23) further includes a flow guide (233), which is a conical structure. The bottom surface of the flow guide (233) is installed at the center of the conical bottom surface of the nozzle body (231) and is used to disperse the airflow in the second feed pipe (22) into multiple air channels (234).

11. The method for controlling continuous spinning of para-aramid according to claim 10, characterized in that: The nozzle (23) is rotatably mounted on the end of the second feed pipe (22).

12. The method for controlling continuous spinning of para-aramid according to claim 11, characterized in that: The mixing assembly (2) further comprises a bearing (24), the bearing (24) being mounted on the outside of the end of the second feed pipe (22). A mounting portion (232) is further provided above the bottom surface of the nozzle body (231), the mounting portion (232) being sleeved on the outer circle of the bearing (24) and fixed by a flange (25).

13. The control method for continuous spinning of para-aramid according to claim 12, characterized in that: The inner wall of the conical barrel (211) is provided with a disturbing body (218).

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