Efficient separation and determination method for kidney bean pod suture fibers

Abstract

The invention relates to the technical field of plant fiber separation, and discloses an efficient separation and determination method of kidney bean pod suture fibers, which comprises the following steps: softening and pretreatment of fibers: softening kidney bean pods by using a specific medium; the tension field controls stripping, and fiber stripping is completed through the gradient tension effect; fluid-assisted separation is carried out, and the fiber fracture risk is reduced through the fluid effect; electric field purification: separating fibers from impurities through electric field force; the method comprises the following steps: carrying out fiber softening and pretreatment on kidney bean pods, carrying out parameter optimization and performance verification, establishing a multi-objective optimization model and verifying a separation effect, and carrying out fiber softening and pretreatment: soaking the kidney bean pods in a salt solution with the concentration of 1%-5%, and controlling the temperature of the salt solution to be 35-40 DEG C. Through tension field controlled stripping, fluid assisted separation and electric field purification, high efficiency, integrity and high purity of fiber separation are realized, and the production requirements of high-quality fiber materials are met.

Description

Technical Field

[0001] The present invention relates to the technical field of plant fiber separation, and particularly to an efficient separation and determination method for the suture fiber of kidney bean pods. Background Art

[0002] With the wide application of natural fiber materials, the separation and utilization of plant fibers have gradually become a research hotspot. The suture fiber of kidney bean pods has important application prospects in textiles, composite materials, and environmental protection products due to its excellent strength, flexibility, and biodegradability. However, there are certain technical challenges in the separation process of this fiber. In life, a technology that can both protect the integrity of the fiber and efficiently extract and purify the fiber is needed to meet the production requirements of high-value-added materials.

[0003] In the separation of plant fibers in the prior art, two mainstream processes, namely chemical treatment method and mechanical peeling method, have been developed. The chemical treatment method softens the seed coat and the fiber bonding part through acid-base solutions, making the fiber easier to separate. Its advantages are significant treatment effect and wide application range. The mechanical peeling method directly applies physical force to peel the fiber from the seed coat, and its characteristic is simple operation and no dependence on complex equipment.

[0004] However, there are still obvious deficiencies in the prior art in the process of separating kidney bean pod fibers; firstly, the force field control of the mechanical peeling method lacks scientificity, and it is unable to effectively reduce fiber breakage, resulting in poor fiber integrity; secondly, although the chemical treatment method has good separation effect, it uses a large amount of chemical reagents to damage the fiber structure and cause relatively large environmental pollution; in addition, the existing purification technologies mostly rely on screening and density separation, with low efficiency and incomplete separation results, and impurities often remain on the fiber surface; finally, the regulation of parameters often relies on experience, and the process standardization degree is low, resulting in unstable separation results and difficulty in large-scale production. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides an efficient separation and determination method for the suture fiber of kidney bean pods, which solves the problems of high fiber breakage rate, large environmental pollution, incomplete impurity purification, and difficulty in standardizing process parameters existing in the prior art in the separation of kidney bean pod fibers.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: An efficient separation and determination method for the suture fiber of kidney bean pods, comprising the following steps: Fiber softening and pretreatment, using a specific medium to soften the kidney bean pods; Tension field control peeling, completing fiber peeling through the action of gradient tension; Fluid-assisted separation, using the action of fluid to reduce the risk of fiber breakage; Electric field purification, separating fibers from impurities by electric field force; Parameter optimization and performance verification, establishing a multi-objective optimization model and verifying the separation effect.

[0007] Preferably, the fiber softening and pretreatment include: Soaking the kidney bean pods in a salt solution with a concentration of 1% - 5%, and controlling the temperature of the salt solution at 35°C - 40°C; The soaking time is 10 - 20 hours to soften the fiber adhesion substances in the kidney bean pods; Cooperating with ultrasonic oscillation for auxiliary softening, the ultrasonic oscillation frequency is 15 - 25 kHz, the amplitude is 40 - 60 μm, and the action time is 5 - 15 minutes.

[0008] Preferably, the tension field controlled peeling includes: Calculating the critical load of the fiber based on the elastic modulus, cross-sectional moment of inertia, and fiber length of the fiber material; Setting the upper limit of the tension during the peeling process to 70% - 90% of the critical load; Applying an initial tension starting from the ridge part of the kidney bean pod and gradually increasing it, with the tension change range being 0.05 N - 0.3 N.

[0009] Preferably, the tension field controlled peeling further includes: The initial tension starts from 0.05 N - 0.1 N, and the tension change rate gradually increases according to the fiber length distribution; The tension application direction progresses from the ridge part to the suture direction, so that the fiber maintains a gradually released stress state during the peeling process; The tension application process is completed in cooperation with a gradually applying force system.

[0010] Preferably, the fluid-assisted separation includes: Injecting a fluid with a dynamic viscosity of 0.5 - 2 Pa·s into the fiber separation tank, and the fluid flow rate is 0.3 - 1 m / s; The fluid exerts a uniform resistance on the fiber surface, and the fiber diameter range is set to 0.005 - 0.02 mm; The fluid action makes the fiber suspended in the separation tank, reducing the contact between the fiber and the tank wall.

[0011] Preferably, the fluid-assisted separation further includes: Calculating the resistance on the fiber surface according to the radius of the fiber and the fluid velocity to ensure that the force on the fiber under the fluid action is lower than the critical load of the fiber material; The separation tank is designed as a closed structure to prevent the fiber from generating chaotic motion due to external interference; Adjusting the fluid velocity gradient distribution to avoid fiber breakage due to local flow velocity differences during the separation process.

[0012] Preferably, the electric field purification includes: Applying an electrostatic field in the area after fiber separation, with the electric field strength set to 300 - 1500 V / m; The charge density difference between impurities and fibers is separated through Coulomb force, and the fibers are not affected by the electric field force; The impurities are adsorbed to the collection area of the purification device by the electric field force.

[0013] Preferably, the electric field purification further includes: The surface charge amount of impurities is increased through surface activation treatment to ensure that the charge density of impurities is significantly higher than that of fibers; The electric field purification process adopts a bipolar electric field design to ensure complete separation of fibers and impurities; The adsorption rate of impurities is optimized through a device that adjusts the electric field force in real time.

[0014] Preferably, the parameter optimization and performance verification include: Establishing a multi-objective optimization model with tension, electric field, and fluid velocity as optimization parameters; By calculating the influence of tension on the fiber fracture rate, the influence of electric field strength on the separation efficiency, and the influence of fluid velocity on the fiber integrity, determining the optimal parameter combination; Using the particle swarm optimization algorithm to complete parameter search and verification.

[0015] Preferably, the performance verification includes: Measuring the fiber fracture rate, observing the morphological characteristics of the separated fibers using an optical microscope, with the target of a fracture rate less than 10%; Measuring the fiber purity, verifying the separation efficiency by weighing the mass ratio of the separated fibers to impurities, with the target of a fiber purity not less than 90%.

[0016] The present invention provides an efficient separation and determination method for kidney bean pod suture fibers. It has the following beneficial effects: 1. The present invention adopts a peeling technique based on gradient tension control. By scientifically applying tension and combining with the elastic characteristics of fibers, the fibers are precisely peeled from the seed coat. Compared with traditional mechanical peeling, this technique effectively reduces the fiber fracture rate and ensures the uniformity of the peeling process, especially suitable for application scenarios with high requirements for fiber integrity.

[0017] 2. The present invention optimizes the impurity migration path through the electrostatic field purification technique, taking advantage of the charge difference between fibers and impurities. This method avoids complex multi-stage screening operations, improves the separation accuracy, and can quickly obtain high-purity fibers. Compared with traditional methods, this technique is more efficient, simpler to operate, and causes no additional damage to fiber properties.

[0018] 3. The present invention designs a multi-objective optimization model, and combines the particle swarm optimization algorithm to globally adjust key parameters such as tension, flow rate, and electric field strength, so that the separation effect achieves the comprehensive objectives of low fiber breakage rate and high separation efficiency. Compared with the existing technologies that rely on empirical regulation, this optimization model can scientifically determine the optimal parameter combination, realizing the high applicability and repeatability of the technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flowchart of the method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the specification of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0021] Please refer to the attached Figure 1 , the embodiment of the present invention provides an efficient separation and determination method for the suture fibers of kidney bean pods, including the following steps: S1. Fiber softening and pretreatment, using a specific medium to soften the kidney bean pods; The separation of the suture fibers of kidney bean pods is to soften the kidney bean pods through a specific medium, reduce the binding force between the fibers and the seed coat, and provide favorable conditions for the complete separation of the fibers. Generally, the softening treatment needs to take into account the mechanical properties of the fibers and the physical and chemical properties of the seed coat. The specific implementation is as follows: In this embodiment, a salt solution is selected as the softening medium. The salt solution can effectively adjust the osmotic pressure of the cell wall, destroy the pectin and hemicellulose structures in the seed coat, and reduce the binding strength between the fibers and the seed coat.

[0022] As an option, the concentration of the salt solution is set in the range of 1% to 5%. In some embodiments, a concentration of 3% can be selected as the preferred value to balance the dissolution ability and fiber integrity.

[0023] Specifically, the temperature of the salt solution is controlled between 35°C and 40°C. Too low a temperature will prolong the softening time, while too high a temperature may cause a decline in fiber performance. In a possible implementation, a constant temperature water bath device can be used to maintain the uniform temperature of the salt solution.

[0024] Generally, the soaking time is set between 10 and 20 hours. In some embodiments, the time can be appropriately adjusted according to the size of the pods, the thickness of the fibers, and the selected concentration. For thicker kidney bean pods, it is recommended to select the upper limit time of 20 hours.

[0025] In this embodiment, after the salt solution immersion is completed, ultrasonic-assisted softening treatment is further adopted. Specifically, ultrasonic oscillation can generate a cavitation effect, and the high-speed bursting of minute bubbles impacts the surface of the seed coat, thereby accelerating the separation of fibers from the adherent tissues.

[0026] As an implementation method, the frequency range of the ultrasonic oscillation device is preferably 15 - 25 kHz. In a preferred embodiment, the frequency can be set to 20 kHz to achieve a balance between cavitation efficiency and fiber protection.

[0027] The range of the amplitude is preferably 40 - 60 μm. In some embodiments, setting the amplitude to 50 μm is more suitable for the processing requirements of finer fibers.

[0028] The action time of the ultrasonic wave can be controlled within 5 - 15 minutes. In a possible way, an action time of 10 minutes can effectively promote the separation of fibers from the seed coat while avoiding damage to the fibers caused by excessive action.

[0029] The cavitation pressure can be calculated by the following formula:

[0030] Where: represents the cavitation pressure, with the unit of Pascal (Pa); represents the static pressure of the salt solution, with the unit of Pascal (Pa); represents the density of the salt solution, with the unit of kilogram per cubic meter (kg / m 3 ) and takes a value of 1000 kg / m in this embodiment 3 ; represents the propagation speed of the ultrasonic wave in the liquid, with the unit of meter per second (m / s) and can take a value of 1500 m / s in the salt solution; represents the angular frequency of the ultrasonic wave, with the unit of radian per second (rad / s), and its calculation formula is , where is the ultrasonic frequency, with the unit of Hertz (Hz); represents the ultrasonic amplitude, with the unit of meter (m).

[0031] Generally, by adjusting the combination of frequency and amplitude, the magnitude of the cavitation pressure can be controlled. In some preferred embodiments, the cavitation pressure should be maintained within a reasonable range to ensure a balance between fiber integrity and softening efficiency.

[0032] Specifically, this step realizes cooperative treatment through the long-time immersion effect of the salt solution and the short-time ultrasonic impact. In some embodiments, after the ultrasonic-assisted treatment, static treatment can be continued to further relax the fiber binding force by utilizing the time window for residual pectin dissolution.

[0033] In a possible implementation, after the softening treatment of the fiber, its adhesion strength can be reduced to 50% of the initial value. At this time, there is no obvious mechanical damage on the fiber surface, and it has good subsequent separation conditions.

[0034] As an option, the salt solution in this step can be replaced by other weak alkaline solutions (such as diluted sodium bicarbonate solution) to achieve a similar softening effect. For different kidney bean varieties, the concentration and temperature range of the salt solution can also be appropriately adjusted. For example, for relatively tender kidney beans, a lower concentration (1% - 3%) and a shorter time (10 - 15 hours) can be selected.

[0035] In another implementation, the ultrasonic treatment can be carried out in different media. For example, selecting other liquids with a viscosity similar to that of the salt solution (such as diluted glycerol solution) can also produce a similar cavitation effect.

[0036] Through the above implementation steps, fiber softening and pretreatment can fully meet the requirements of subsequent separation processes, laying a foundation for achieving efficient separation.

[0037] S2. Tension field controlled peeling, and fiber peeling is completed through the action of gradient tension; In this step, tension field controlled peeling is adopted. Through the gradual application of gradient tension, the fiber gradually detaches from the seed coat within a controlled tension range while maintaining the integrity of the fiber. Generally, when applying tension, the physical properties and dimensional parameters of the fiber need to be considered to ensure that the fiber will not break due to excessive force.

[0038] In this embodiment, the application of tension is based on the elastic characteristics of the fiber. Specifically, the design of tension control is based on Euler's elastic stability theory, and the stress range is determined in combination with the critical load of the fiber. The calculation formula for the critical load is as follows:

[0039] Where: represents the critical load of the fiber, with the unit of Newton (N); represents the elastic modulus of the fiber, with the unit of Pascal (Pa); represents the moment of inertia of the cross-section of the fiber, with the unit of the fourth power of meter (m 4 ), and its calculation formula is:

[0040] Where: represents the diameter of the fiber, with the unit of meter (m); represents the correction coefficient, which is taken according to the support conditions at both ends of the fiber. In this embodiment = 1.0 (hinged at both ends); Represents the effective length of the fiber, with the unit of meter (m).

[0041] Generally, the elastic modulus of the fiber ranges from 2 to 5 GPa, the diameter of the fiber ranges from 0.005 to 0.02 mm, and the length of the fiber ranges from 4 to 6 cm. Based on the above parameter calculations, the critical load of the fiber ranges from 0.2 to 0.5 N.

[0042] To avoid fiber breakage, in this embodiment, the applied tension ranges from 70% to 90% of the critical load, that is, 0.14 to 0.45 N. As an option, the maximum applied tension can be set to 80% of the critical load to obtain a better fiber protection effect.

[0043] Specifically, the tension in this embodiment is applied in a gradient form. The initial tension is applied starting from the raphe part, and the tension value is gradually increased until the fiber stripping operation is completed.

[0044] As a way of implementation, the initial tension is set to 0.05 to 0.1 N, and the applied tension increases step by step according to the following linear gradient formula:

[0045] Where: represents the rate of change of tension with the stripping distance, with the unit of Newton per meter (N / m); represents the maximum tension, with the unit of Newton (N), and its value in this embodiment does not exceed 90% of the critical load; represents the initial tension, with the unit of Newton (N), and its value in this embodiment is 0.05 to 0.1 N; represents the effective length of the fiber, with the unit of meter (m).

[0046] In some embodiments, the rate of change of tension can be appropriately adjusted according to the non-uniformity of the fiber length. For example, for fibers with shorter lengths, the rate of change of tension can be appropriately increased to accelerate the stripping speed.

[0047] The application direction of the tension starts from the raphe part of the kidney bean pod and gradually advances towards the suture part. In a possible way of implementation, the precise application of the tension gradient can be completed through a step-by-step force application device. Generally, the force application device can adopt a tension adjustment device controlled by a servo motor, or a weight block method can be selected for simulation experiments.

[0048] In this embodiment, the dynamic monitoring of the tension is completed by a sensor. As an option, a strain gauge sensor can be used to measure the change in the applied tension in real time. Specifically, the sensitivity of the sensor needs to be able to detect a tension change of 0.01 N to ensure the accuracy of the applied tension.

[0049] In some embodiments, the tension monitoring results can be synchronously recorded with the peeling position, and the rationality of the tension gradient can be verified through data analysis. For example, at different positions in the fiber length direction, the stress distribution on the fiber surface can be measured to ensure that no stress concentration phenomenon occurs during the peeling process.

[0050] In this embodiment, the stress state of the fiber is verified through experimental tests. Generally, the maximum stress position of the fiber appears at the starting part near the raphe. Therefore, the selection of the initial tension needs to be particularly cautious. In some embodiments, the risk of fiber fracture can be further reduced by reducing the value of the initial tension (such as 0.03 N).

[0051] As a possible optimization method, the particle swarm optimization algorithm can be combined to iteratively adjust the parameters of the applied tension. For example, in the case of fluctuations in the elastic modulus, length, and diameter of the fiber, the optimal range of the tension can be determined through algorithm optimization, thereby improving the peeling efficiency and integrity of the fiber.

[0052] Through the above steps, this embodiment realizes the safe peeling of the fiber and effectively reduces the fracture rate.

[0053] S3. Fluid-assisted separation, using the action of the fluid to reduce the risk of fiber fracture; In this step, through fluid-assisted separation, the buffer effect and suspension effect of the fluid on the fiber are used to reduce the damage to the fiber caused by mechanical contact. Generally, the selection of the fluid and its flow rate need to match the physical properties of the fiber to achieve effective separation.

[0054] In this embodiment, a low-viscosity liquid is preferably used as the separation fluid. Specifically, the dynamic viscosity range is set to 0.5 - 2 Pa·s. As an option, a diluted glycerol solution or a salt solution can be used to ensure that a uniform supporting force is formed on the fiber surface.

[0055] The flow rate range of the fluid is 0.3 - 1 m / s. In some embodiments, selecting the intermediate value of 0.5 - 0.8 m / s can achieve a balance between the fluid acting force and the fiber stability.

[0056] Specifically, the temperature of the fluid is controlled at 30°C - 40°C. A higher temperature can reduce the viscosity of the fluid, but it should not exceed the heat-resistant temperature range of the fiber to prevent the mechanical properties of the fiber from being affected.

[0057] In this embodiment, the force exerted by the fluid on the fiber surface is calculated according to Stokes' law, and its formula is as follows:

[0058] Where: represents the resistance of the fluid to the fiber surface, with the unit of Newton (N); represents the dynamic viscosity of the fluid, with the unit of Pascal-second (Pa·s), and the range in this embodiment is 0.5 - 2 Pa·s; represents the radius of the fiber, with the unit of meter (m), and the range is 0.0025 - 0.01 mm; represents the flow velocity of the fluid, with the unit of meter per second (m / s), and the range is 0.3 - 1 m / s.

[0059] Generally, by adjusting the combination of and , the fluid resistance on the fiber can be precisely controlled. In one possible implementation, by reducing the flow velocity to 0.5 m / s, the force fluctuation on the fiber surface can be reduced, and the stability of the separation process can be improved.

[0060] Specifically, the separation tank in this embodiment adopts a closed design to ensure the uniform distribution of the fluid velocity and avoid the impact of local turbulence on the fiber.

[0061] As an option, the cross-sectional area of the separation tank is set to 10 - 50 cm 2 to provide sufficient suspension space. In some embodiments, the friction coefficient when the fiber contacts the tank wall can be further reduced by increasing the lining material (such as silica gel) of the tank wall.

[0062] To achieve the stable suspension of the fiber, this embodiment adopts a segmented fluid control method. Specifically, the fluid velocity in the separation tank is adjusted section by section by the flow velocity control system at the inlet and outlet. The flow velocity in the first section can be set to 0.3 - 0.5 m / s, and the second section is gradually increased to 0.5 - 0.8 m / s. This flow velocity gradient design can reduce the impact when the fiber transitions from the stationary state to the suspended state.

[0063] During the fluid-assisted separation process, due to the lower density, the fiber can be suspended in the fluid, while the impurities gradually settle due to the higher density. As a possible implementation, the bottom of the separation tank is designed to be inclined so that the impurities can gather in a specific area for subsequent cleaning.

[0064] In some embodiments, a filter mesh structure can be added to the separation tank to intercept large particle impurities without interfering with the suspended movement of the fiber. The aperture of the filter mesh is preferably 0.02 - 0.05 mm to avoid misintercepting the fiber.

[0065] In this embodiment, the fluid velocity in the separation tank is monitored in real time by a flowmeter. As an option, an ultrasonic flowmeter can be used, whose accuracy can reach 0.01 m / s and is suitable for monitoring low-speed fluids.

[0066] In a possible implementation, the particle swarm optimization algorithm is used to optimize the parameters of the dynamic viscosity of the fluid, the flow velocity, and the suspension time of the fibers. The optimization goal is to maximize the integrity of the fibers and the sedimentation rate of the impurities, while minimizing the lateral drift distance of the fibers.

[0067] Through the above implementation steps, this embodiment effectively reduces the risk of fiber breakage by the action of the fluid, and at the same time realizes the preliminary separation of fibers and impurities.

[0068] S4. Electric field purification, separating fibers and impurities by electric field force; This step further purifies the fibers by the action of electric field force, and realizes efficient separation by using the differences in charge distribution and response intensity between the fibers and the impurities. Generally, in the process of electric field purification, the electric field strength, the charge density difference between the fibers and the impurities, and the action area of the electric field need to be accurately controlled.

[0069] In this embodiment, an electrostatic field device is used to complete the separation of fibers and impurities. Specifically, the range of the electric field strength is preferably 300 - 1500 V / m to ensure that the impurities can be adsorbed by sufficient Coulomb force.

[0070] Generally, the strength of the electric field needs to be optimized according to the charge density difference between the fibers and the impurities. The impurities usually improve the charge density through surface treatment to make them respond to a stronger electric field force, while the charge density of the fibers is relatively low and remains basically stable in the electric field.

[0071] The magnitude of the electric field force is calculated according to Coulomb's law, and the specific formula is as follows:

[0072] Where: represents the electric field force, with the unit of Newton (N); represents the surface charge quantity of the fiber, with the unit of Coulomb (C); represents the surface charge quantity of the impurity, with the unit of Coulomb (C); represents the vacuum permittivity, with a value of 8.8×10 -12 ; represents the distance between the fiber and the impurity, with the unit of meter (m).

[0073] In some embodiments, the value of q2q_2q2 can be increased by adjusting the type of surfactant for the impurities. As an option, cationic surfactants can be used to significantly increase the surface charge density of the impurities.

[0074] Specifically, the action time of the electric field is set to 5 - 15 seconds. If the time is too short, it may cause incomplete migration of the impurities, while if it is too long, it may increase the energy consumption.

[0075] In this embodiment, the electric field device consists of positive and negative electrodes, and the distance between them is preferably 10 - 50 cm. The surface of the electrode plate is smoothed to prevent accidental adsorption of fibers.

[0076] As a possible implementation, impurity collectors are equipped in the two - pole regions of the electric field device. Specifically, the collector is designed with a porous structure to effectively prevent the secondary reflux of impurities and ensure the complete separation of fibers and impurities.

[0077] Generally, when the fiber passes through the electric field region, its movement speed is controlled at 0.1 - 0.5 m / s. This speed range can balance the action time of the electric field force and the separation efficiency.

[0078] In some embodiments, the electric field intensity can be dynamically adjusted according to the impurity content of the fiber. For example, when the impurity content is high, the electric field intensity can be adjusted to 1000 - 1500 V / m to accelerate the impurity migration process.

[0079] Specifically, this embodiment further improves the separation accuracy through the design of a bipolar electric field. The bipolar electric field can alternately change the direction of the electric field within one cycle, thereby preventing some impurities from remaining on the fiber surface due to the electrostatic shielding effect.

[0080] In this embodiment, the effect of electric field purification is verified through the following two indicators: Fiber purity: Calculate the mass ratio of the separated fiber to the residual impurities by the weighing method. The target purity is ≥95%.

[0081] Separation efficiency: Statistically analyze the migration rate and adsorption amount of impurities to evaluate the efficiency of the electric field action. The target efficiency is ≥90%.

[0082] As an implementation, this embodiment uses the particle swarm optimization algorithm to comprehensively optimize the electric field intensity, action time, and fiber movement speed. The optimization goal is to maximize the separation efficiency while minimizing the risk of mechanical damage to the fiber.

[0083] As an option, the electric field device in this embodiment can be integrated with an automatic monitoring module for real - time recording of the charge distribution of fibers and impurities. In some embodiments, optical imaging technology can be combined to dynamically analyze the migration trajectory of impurities during the separation process.

[0084] In addition, to further enhance the effect of the electric field, an electrostatic spraying device can be introduced before the fibers pass through the electric field in this embodiment, so that a small amount of negative charges are carried on the fiber surface, enhancing its stability in the electric field.

[0085] Through the above implementation steps, this embodiment realizes the fine separation of fibers and impurities by using the electric field force.

[0086] S5. Parameter optimization and performance verification, establishing a multi-objective optimization model and verifying the separation effect; In this step, the key parameters are comprehensively optimized by establishing a multi-objective optimization model, and at the same time, experimental verification is combined to ensure the reliability and repeatability of the separation performance. Generally, in the optimization process, the trade-off relationship between parameters needs to be comprehensively considered, and scientific algorithms are used to achieve the global optimization of the objective function.

[0087] In this embodiment, the optimization objectives include the following three aspects: Minimizing the fiber breakage rate: By adjusting parameters such as the tension gradient and fluid velocity, mechanical damage to the fibers during the separation process is reduced.

[0088] Maximizing the separation efficiency: Improving the separation effect of fibers and impurities and increasing the purity of the fibers.

[0089] Minimizing the impurity residue: Optimizing the electric field parameters to minimize the impurity content in the fibers after separation.

[0090] As an option, the above objectives are combined into the following multi-objective optimization model:

[0091] Where: represents the total objective function value; represents the influence of tension on the fiber breakage rate; represents the contribution of fluid velocity to the separation efficiency; represents the influence of electric field strength on the impurity residue.

[0092] To ensure the rationality of the model, the ranges of each parameter are determined by combining experiments and theoretical calculations. The specific parameter ranges include: Tension : The range is 0.05 - 0.3 N, ensuring that the actual force on the fiber is lower than 90% of its critical load.

[0093] Fluid velocity : The range is 0.3 - 1 m / s, which not only ensures the suspension effect of the fibers but also avoids disturbances caused by excessive flow velocity.

[0094] Electric field strength : ranging from 300 to 1500 V / m to ensure that impurities are completely migrated under the action of the electric field force.

[0095] Generally, physical constraints need to be added during the optimization process. For example, the rate of change of tension needs to satisfy the following relationship:

[0096] Where: represents the rate of change of tension with respect to the peeling length, with the unit of Newton per meter (N / m); and represent the maximum value and the initial value of tension respectively; represents the length of the fiber, with the unit of meter (m).

[0097] In this embodiment, the particle swarm optimization algorithm (PSO) is used for global search and optimization of parameters. Specifically, the particle swarm algorithm gradually approaches the optimal solution of the objective function by simulating the movement of a particle swarm in a multi-dimensional parameter space.

[0098] In a possible implementation, the optimization process includes the following steps: Initialize the particle swarm, with each particle corresponding to a parameter combination .

[0099] Calculate the fitness value of each particle, that is, the objective function .

[0100] Update the position and velocity of the particles to gradually approach the global optimal solution.

[0101] Output the optimization result after converging to the optimal solution.

[0102] The size of the particle swarm is preferably 20 to 50, and the maximum number of iterations for each particle is set to 100 to 200. In some embodiments, the optimization accuracy can be improved by increasing the number of the particle swarm.

[0103] The optimization result is evaluated through experimental verification. The verification process includes the following aspects: Test of the fiber breakage rate: Use an optical microscope to observe the morphology of the separated fibers and count the proportion of broken fibers. The target breakage rate is controlled at ≤5%.

[0104] Calculation of the separation efficiency: Calculate the purity of the separated fibers by the weighing method, with the target being ≥95%.

[0105] Determination of the impurity residue: Measure the impurity content in the fibers by the mass ratio method, with the target being ≤3%.

[0106] In a possible implementation, the experimental results can also be used to correct and optimize the parameter range of the model. For example, if the boundary values of a certain parameter have a significant impact on performance, the applicability of the model can be improved by expanding or narrowing the parameter range.

[0107] In this embodiment, the optimized parameter combination is as follows: The tension range is 0.1 - 0.25 N, the initial tension is 0.1 N, and the tension gradient is 0.05 N / m; The fluid velocity is 0.5 - 0.7 m / s, which can achieve stable suspension of the fibers; The electric field strength is 800 - 1200 V / m, which can complete impurity migration in a short time.

[0108] As an extension, the parameter optimization process can also be verified in combination with other methods. For example, in some embodiments, the response surface analysis method can be used to further study the interaction of key parameters.

[0109] Through the above steps, this embodiment realizes the comprehensive optimization of the fiber separation performance.

[0110] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for efficiently separating and measuring bean pod suture fibers, characterized in that: The following steps are involved: Fiber softening and pretreatment, softening of bean pods using specific media; The tension field controls the stripping, and the fiber stripping is completed through the gradient tension effect; Fluid-assisted separation uses fluid action to reduce the risk of fiber breakage; Electric field purification, separating fibers and impurities through electric field force; Parameter optimization and performance verification, establish a multi-objective optimization model and verify the separation effect.

2. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The fiber softening and pretreatment comprises: Soaking bean pods in a salt solution with a concentration of 1% to 5%, wherein the temperature of the salt solution is controlled at 35° C. to 40° C.; Soaking time is 10 to 20 hours to soften the fibrous adhesions in the bean pods; With the help of ultrasonic oscillation to assist softening, the ultrasonic oscillation frequency is 15-25kHz, the amplitude is 40-60μm, and the action time is 5-15 minutes.

3. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The tension field controlled peeling comprises: Calculate the critical load of the fiber based on the elastic modulus, section moment of inertia and fiber length of the fiber material; The upper limit of the tension during the peeling process is set to 70% to 90% of the critical load; Initial tension is applied starting from the seed ridge of the bean pod and gradually increased within a tension range of 0.05N to 0.3N.

4. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The tension field controlled peeling further comprises: The initial tension starts from 0.05N to 0.1N, and the rate of tension change gradually increases according to the fiber length distribution; The direction of tension application progresses from the seed ridge to the suture line, so that the fibers are kept in a state of gradually released stress during the stripping process; The tension application process is completed with the gradual force application system.

5. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The fluid-assisted separation comprises: Inject a fluid with a dynamic viscosity of 0.5 to 2 Pa·s into the fiber separation tank, and the fluid flow rate is 0.3 to 1 m / s; The fluid exerts uniform resistance on the fiber surface, and the fiber diameter range is set to 0.005 to 0.02 mm; The fluid action makes the fibers suspended in the separation groove, reducing the contact between the fibers and the groove wall.

6. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The fluid-assisted separation further comprises: The resistance on the fiber surface is calculated based on the fiber radius and fluid velocity to ensure that the force on the fiber under the action of the fluid is lower than the critical load of the fiber material; The separation tank is designed as a closed structure to prevent the fibers from moving in disorder due to external interference; Adjust the fluid velocity gradient distribution to avoid fiber breakage due to local flow velocity differences during the separation process.

7. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The electric field purification comprises: Apply an electrostatic field to the area after fiber separation, and the electric field strength is set to 300-1500 V / m; The difference in charge density between impurities and fibers is separated by Coulomb force, and the fibers are not affected by the electric field force. The impurities are attracted to the collection area of ​​the purification device by the electric field.

8. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The electric field purification further comprises: The surface charge of the impurities is increased by surface active treatment, ensuring that the charge density of the impurities is significantly higher than that of the fibers; The electric field purification process uses a bipolar electric field design to ensure that the fibers are completely separated from impurities; The device optimizes the adsorption rate of impurities by real-time regulation of the electric field force.

9. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The parameter optimization and performance verification include: A multi-objective optimization model was established, with tension, electric field, and fluid velocity as optimization parameters; The optimal parameter combination is determined by calculating the effect of tension on fiber breakage rate, the effect of electric field strength on separation efficiency, and the effect of fluid velocity on fiber integrity; Particle swarm optimization algorithm is used to complete parameter search and verification.

10. The method for efficiently separating and measuring bean pod suture fibers according to claim 1, characterized in that: The performance verification includes: Determine the fiber breakage rate and use an optical microscope to observe the morphological characteristics of the separated fibers. The goal is a breakage rate of less than 10%; The fiber purity is determined and the separation efficiency is verified by weighing the mass ratio of separated fiber to impurities. The goal is that the fiber purity is not less than 90%.

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