Blended fabric separation equipment and method

Abstract

The invention discloses a blended fabric separation device and method. The blended fabric separation device comprises a reaction tank, a multi-cylinder tank body, a blade type stirrer, a filter, at least one ultrasonic oscillator and a backflow pipeline. And the multi-cylinder tank body is arranged in the reaction tank. The blade type stirrer is arranged in the multi-cylinder tank body, and the blade type stirrer has at least two rotation directions. The filter is arranged at the bottom of the reaction tank. The ultrasonic oscillator is connected with the reaction tank, wherein the ultrasonic oscillator has an oscillation frequency of 10 kHz to 50 kHz. The reflux pipeline is connected with the filter and the reaction tank. According to the separation equipment and method for the blended fabric, the separation time of the blended fabric can be shortened, the use amount of the solvent can be reduced, the separation efficiency of the blended fabric is improved, and sustainable development of the environment is promoted.

Description

Technical Field

[0001] This disclosure relates to a separation apparatus and method for textiles, and more particularly to a separation apparatus and method for blended fabrics. Background Technology

[0002] Currently, common blended fabric separation equipment typically relies on unidirectional rotational motion to complete the separation process. However, this method is limited by its lack of omnidirectional reciprocating motion, thus failing to ensure uniform impregnation of the chemical into the blended fabric. Because the rotational motion can only apply force in a specific direction, the chemical struggles to penetrate the deeper fibers of the blended fabric, thereby reducing separation effectiveness and efficiency. This limitation leads to reduced chemical utilization, affecting separation quality, and necessitates continuous chemical replenishment, increasing costs. Therefore, existing blended fabric separation equipment requires further design improvements to achieve more uniform and comprehensive processing results. Summary of the Invention

[0003] According to some embodiments disclosed herein, a separation device for blended fabrics includes a reaction tank, a multi-cylindrical tank, a blade-type agitator, a filter, at least one ultrasonic oscillator, and a return line. The multi-cylindrical tank is disposed within the reaction tank. The blade-type agitator is disposed within the multi-cylindrical tank, wherein the blade-type agitator has at least two rotational directions. The filter is disposed at the bottom of the reaction tank. The ultrasonic oscillator is connected to the reaction tank, wherein the ultrasonic oscillator has an oscillation frequency of 10 kHz to 50 kHz. The return line connects the filter and the reaction tank.

[0004] In some embodiments disclosed herein, the ultrasonic oscillator is adjacent to the filter.

[0005] In some embodiments disclosed herein, the blades of the blade-type stirrer are positioned higher than the connection point between the ultrasonic oscillator and the reaction tank.

[0006] In some embodiments disclosed herein, the ultrasonic oscillator and the blade-type stirrer are disposed at the bottom of the reaction tank, and the bottom of the reaction tank falls within 0% to 50% of the total height of the reaction tank.

[0007] In some embodiments disclosed herein, the oscillation frequency of the ultrasonic oscillator is a constant.

[0008] According to other embodiments of this disclosure, a method for separating blended fabrics includes: placing the blended fabric and a solvent into a reaction tank, allowing the blended fabric to react in the solvent to separate into polyester fabric and cellulose material; activating at least one ultrasonic oscillator connected to the reaction tank, providing an oscillation frequency of 10 kHz to 50 kHz; after activating the ultrasonic oscillator, activating a blade-type stirrer located in the reaction tank, wherein the blade-type stirrer rotates in at least two directions of rotation; collecting the cellulose material using a filter located at the bottom of the reaction tank; and returning the solvent after reaction to the reaction tank through a return line connecting the filter and the reaction tank.

[0009] In some embodiments disclosed herein, the ultrasonic oscillator generates multiple cavitation bubbles in a solvent, and the diameter of the cavitation bubbles is from 5 micrometers to 500 micrometers.

[0010] In some embodiments disclosed herein, the blade-type agitator repeatedly performs the following steps: rotating clockwise for a first time; and rotating counterclockwise for a second time, wherein the first time and the second time are the same.

[0011] In some embodiments disclosed herein, the oscillation frequency provided by the ultrasonic oscillator is a constant.

[0012] In some embodiments disclosed herein, the method for separating blended fabrics further includes: after the solvent after the reaction is discharged from the reaction tank, activating the multi-cylinder tank located in the reaction tank to remove excess solvent remaining on the polyester fabric.

[0013] According to the embodiments disclosed above, the alternating forward and reverse rotation of the blade-type agitator in the blended fabric separation device can improve the problem of insufficient solvent (reagent) wetting of the blended fabric due to spin deformation during separation. Furthermore, by providing a suitable ultrasonic oscillation frequency to the reaction tank, cavitation bubbles of appropriate size can be generated. These cavitation bubbles can be further introduced into the blended fabric and generate high-energy sound pressure upon bursting. This sound pressure rapidly introduces the solvent into the blended fabric, increasing the contact area between the blended fabric and the solvent, accelerating the reaction, and allowing the resulting cellulose material to detach from the blended fabric through vibration. In addition, cavitation bubbles of appropriate size can avoid generating excessively high sound pressure, thereby preventing structural damage to the recycled material (e.g., polyester fabric). This reduces the separation time and solvent usage of the blended fabric, thereby improving the separation efficiency and promoting environmental sustainability. Attached Figure Description

[0014] To make the above and other objects, features, advantages and embodiments disclosed herein more apparent and understandable, the accompanying drawings are described below:

[0015] Figure 1This is a side perspective schematic diagram of a separation device for blended fabrics according to some embodiments of the present disclosure;

[0016] Figure 2 This is a schematic flowchart of a method for separating blended fabrics according to some embodiments of this disclosure.

[0017] Figure 3A The pH value versus time graphs for Examples 7-9 and Comparative Example 10 are shown; and

[0018] Figure 3B The graph shows the dissolution rate versus time for Examples 7-9 and Comparative Example 10.

[0019] [Symbol Explanation]

[0020] 100: Separation equipment for blended fabrics

[0021] 110: Reaction tank

[0022] 111: Sidewall

[0023] 120: Multi-cylindrical groove

[0024] 120a: Cylindrical structure

[0025] 120b: Cylindrical cavity

[0026] 130: Blade type agitator

[0027] 132: Blade

[0028] 132T: Top

[0029] 140: Filter

[0030] 150: Ultrasonic Oscillator

[0031] 150T: Top

[0032] 160: Return line

[0033] 170: Drive unit

[0034] 180: Pressure detector

[0035] 190: pH value detector

[0036] 200: Water level detector

[0037] J: Cage-like structure

[0038] H: Total height

[0039] X: Vertical distance

[0040] B: Bottom position

[0041] P: Connection position

[0042] D1: Vertical

[0043] S10~S50: Steps Detailed Implementation

[0044] The following describes several embodiments of this disclosure with reference to the accompanying drawings. For clarity, many practical details will be described in the following description. However, it should be understood that these practical details should not be used to limit this disclosure. That is, in some embodiments of this disclosure, these practical details are not essential and therefore should not be used to limit this disclosure. In addition, for the sake of simplicity in the drawings, some conventional structures and components will be shown in a simplified schematic manner. Furthermore, for the reader's convenience, the dimensions of the components in the drawings are not drawn to scale.

[0045] It should be understood that although the terms “first,” “second,” and “third,” etc., may be used herein to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, and / or parts should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer, or part from another element, component, region, layer, or part. Therefore, the terms “first element,” “component,” “region,” “layer,” or “part” used below may also be referred to as a second element, component, region, layer, or part without departing from the teachings of this document.

[0046] It should be understood that relative terms such as “down” or “bottom” and “up” or “top” may be used herein to describe the relationship of one element to another, as illustrated in the accompanying drawings. It should be understood that relative terms are intended to include different orientations of the device beyond those shown in the figures. For example, if a device in one of the figures is flipped, an element described as being “down” to other elements will be oriented “up” to other elements. Thus, the exemplary term “down” can include both “down” and “up” orientations, depending on the specific orientation of the figure. Similarly, if a device in one of the figures is flipped, an element described as being “down” or “below” to other elements will be oriented “above” to other elements. Thus, the exemplary term “down” or “below” can include both “up” and “down” orientations.

[0047] This disclosure provides a separation apparatus and method for blended fabrics, wherein the blended fabrics include polyester and cellulose materials. By using the alternating forward and reverse rotation of a blade-type agitator in the blended fabric separation apparatus, the problem of insufficient solvent (reagent) wetting of the blended fabric due to spin deformation during separation can be improved. Furthermore, by providing a suitable ultrasonic oscillation frequency to the reaction tank, cavitation bubbles of appropriate size can be generated. These cavitation bubbles can be further introduced into the blended fabric, generating high-energy sound pressure upon bursting. This sound pressure rapidly introduces the solvent into the blended fabric, increasing the contact area between the blended fabric and the solvent, accelerating the reaction, and allowing the cellulose material produced after the reaction to detach from the blended fabric through vibration. In addition, cavitation bubbles of appropriate size can avoid generating excessively high sound pressure, thereby preventing structural damage to the recycled material (e.g., polyester fabric). This reduces the separation time and solvent usage, thereby improving the separation efficiency of the blended fabric and promoting environmental sustainability.

[0048] Please see Figure 1 This is a side perspective view of a blended fabric separation device 100 according to some embodiments of the present disclosure. The blended fabric separation device 100 includes a reaction tank 110, a multi-cylinder tank 120, a blade agitator 130, a filter 140, at least one ultrasonic oscillator 150, and a return pipeline 160. The configuration and details of the above-mentioned components (devices) and pipelines will be described in sequence below.

[0049] The reaction tank 110 is configured to hold a solvent (reagent) to separate (decompose) the blended fabric into polyester and cellulose materials. That is, the blended fabric separation device 100 disclosed herein can be applied to separate blended fabrics containing polyester and cellulose materials. In some embodiments, the blended fabric may include polyethylene terephthalate and cotton. In other embodiments, the blended fabric may include polyethylene terephthalate and rayon. The blended fabric separation device 100 disclosed herein can achieve good separation results for blended fabrics containing the above-mentioned components. In some embodiments, the reaction tank 110 may be a U-shaped mixing tank to provide higher fluidity and mixing effect for the solvent and blended fabric. Furthermore, the U-shaped mixing tank shape facilitates the use of various types of stirring elements, such as the multi-cylindrical tank 120 and the blade-type stirrer 130 disclosed herein.

[0050] A multi-cylindrical tank 120 is disposed within a reaction tank 110. In some embodiments, when viewed from a top angle, the multi-cylindrical tank 120 may be positioned at the very center of the reaction tank 110. More specifically, the multi-cylindrical tank 120 is a stirrer comprising a plurality of cylindrical structures 120a, each extending longitudinally along the longitudinal direction D1 of the reaction tank 110, with the major axis of each cylindrical structure 120a parallel to the sidewall 111 of the reaction tank 110, and the plurality of cylindrical structures 120a arranged at intervals to form a plurality of cylindrical cavities 120b. In some embodiments, the multi-cylindrical tank 120 may be, for example, a squirrel-cage stirrer, comprising a cage-like structure J electrically connected to a drive device 170 (e.g., a motor), wherein the cage-like structure J is composed of a plurality of cylindrical structures 120a. It is worth noting that the multi-cylindrical tank 120 disclosed herein is not designed to operate during the separation of the blended fabric to achieve centrifugal extraction. Instead, it is activated and rotated only after the blended fabric and solvent have reacted completely, thus achieving dehydration of the blended fabric. In this regard, the design of multiple cylindrical structures 120a in the multi-cylindrical tank 120 increases the contact area between the blended fabric and the multi-cylindrical tank 120, and evenly distributes the pressure, allowing the blended fabric to be uniformly squeezed within the multiple cylindrical cavities 120b, effectively promoting moisture removal and thereby improving the overall dehydration efficiency.

[0051] A blade-type agitator 130 is disposed in the reaction tank 110 and configured to agitate the solvent and the blended fabric during the separation of the blended fabric, thereby promoting solvent wetting of the blended fabric and preventing the blended fabric from tangling. In some embodiments, when viewed from a top angle, the blade-type agitator 130 may be disposed at the center of the reaction tank 110 and may be surrounded by multiple cylindrical structures 120a. More specifically, the blade-type agitator 130 may be disposed in a cylindrical cavity 120b located at the center of the multi-cylinder tank 120 and may be electrically connected to a drive device 170 (e.g., a motor). In some embodiments, the blade-type agitator 130 and the multi-cylinder tank 120 may be electrically connected to the same drive device 170 (e.g., a motor), and at least one of the blade-type agitator 130 and the multi-cylinder tank 120 may be selectively driven by control elements such as a differential, a two-way clutch, etc. In some embodiments, the rotational speed of the blade agitator 130 can be a constant value, and in the range of 20 rev / min to 120 rev / min, thereby preventing an increase in the probability of the blended fabric knotting or tangling due to excessive rotational speed.

[0052] The blade-type agitator 130 disclosed herein has at least two rotation directions. Specifically, when viewed from a top angle, the two rotation directions of the blade-type agitator 130 can be clockwise and counterclockwise. By designing the blade-type agitator 130 to have at least two rotation directions, a forward / counter-clockwise alternating rotation agitation pattern can be constructed to continuously change the direction of the spin vortex during the separation of the blended fabric. This ensures that the blended fabric does not undergo unintended deformations such as folding, twisting, agglomeration, or lamination due to continuous spin compression in the same direction, thereby ensuring that the solvent can fully wet the blended fabric and preventing the solvent from reacting only in specific areas or on specific surfaces of the blended fabric. This reduces the separation time of the blended fabric and the amount of solvent used, thereby improving the separation efficiency of the blended fabric.

[0053] A filter 140 is disposed at the bottom position B of the reaction tank 110 and configured to separate the solvent reacting with the blended fabric and the cellulose material detached from the blended fabric. In some embodiments, the filter 140 may include a coarse filter layer, a medium filter layer, and a fine filter layer, wherein the coarse filter layer may have a screen of, for example, 40 to 300 mesh (e.g., 200 mesh), the medium filter layer may have a screen of, for example, 100 to 900 mesh (e.g., 800 mesh), and the fine filter layer may have a screen of, for example, 900 to 2000 mesh (e.g., 1800 mesh). Thus, each filter layer can collect cellulose material with different particle sizes. For example, the coarse filter layer can collect cellulose material (cotton fibers) with a particle diameter of 0.048 mm to 0.35 mm, the medium filter layer can collect cellulose material with a particle diameter of 0.016 mm to 0.15 mm, and the fine filter layer can collect cellulose material with a particle diameter of 0.0065 mm to 0.016 mm. In some embodiments, a coarse filter layer may be located at the bottom B of the reaction tank 110, while a medium filter layer and a fine filter layer may be located in a return line 160 connected to the coarse filter layer, with the medium filter layer positioned between the coarse and fine filter layers. In this way, the mixture flowing out of the reaction tank 110 can sequentially pass through the coarse, medium, and fine filter layers for a progressive filtration process, achieving a more comprehensive filtration effect and recovering a higher purity solvent. Furthermore, the return line 160 connects the filter 140 and the reaction tank 110 (the connection between the return line 160 and the reaction tank 110 is not shown in the figure; however, the connection position can be adjusted according to the structure of the reaction tank 110), and is configured to return the solvent separated by the filter 140 back to the reaction tank 110 for solvent reuse.

[0054] An ultrasonic oscillator 150 is connected to a reaction tank 110 and configured to generate cavitation bubbles of suitable size at a specific oscillation frequency. These cavitation bubbles, once generated, can be introduced into the blended fabric and, upon bursting, produce high-energy sound pressure. This sound pressure rapidly introduces the solvent into the blended fabric, increasing the contact area between the fabric and the solvent, accelerating the reaction, and allowing the resulting cellulose material to detach from the fabric via oscillation. Specifically, the ultrasonic oscillator 150 has an oscillation frequency ranging from 10 kHz to 50 kHz (e.g., 20 kHz, 30 kHz, 40 kHz). This frequency range helps generate small-sized cavitation bubbles, facilitating penetration and wetting of the blended fabric. Furthermore, the cavitation bubbles generated within this frequency range prevent the generation of excessively high-energy sound pressure upon bursting, thus preventing damage to the structure of the recycled polyester fabric. Specifically, when the oscillation frequency is 10 kHz, cavitation bubbles of 200 to 500 micrometers can be generated; when the oscillation frequency is 20 kHz, cavitation bubbles of 80 to 300 micrometers can be generated; when the oscillation frequency is 40 kHz, cavitation bubbles of 10 to 100 micrometers can be generated; and when the oscillation frequency is 50 kHz, cavitation bubbles of 5 to 100 micrometers can be generated. In a preferred embodiment, the ultrasonic oscillator 150 may have an oscillation frequency of 40 to 50 kHz to generate cavitation bubbles smaller than the size of the cellulose material, thereby facilitating the detachment (peeling) of the cellulose material by oscillation. It should be understood that the size of the cavitation bubbles disclosed herein is obtained by shooting and measuring with a high-speed camera (frame rate of 2250 frames per second), and is indicated and measured by the reflection of the light source when the cavitation bubbles are generated and burst.

[0055] It's worth noting that when the oscillation frequency is too low, although the generated cavitation bubbles can travel a longer distance, the generation rate of cavitation bubbles is low, and the size of the generated cavitation bubbles is too large to penetrate the blended fabric. Conversely, when the oscillation frequency is too high, although smaller cavitation bubbles can be generated, they cannot travel long distances. Furthermore, appropriately sized cavitation bubbles not only allow the cellulose material in the blended fabric to detach through oscillation, but also, upon bursting, open the pores between the warp and weft yarns in the blended fabric, further increasing the peeling probability of the cellulose material and achieving a better separation effect. Additionally, by providing a suitable oscillation frequency, the reaction temperature can be ensured to remain between 32°C and 46°C, meaning the overall reaction temperature will not exceed 50°C. This avoids thermal damage to the blended fabric caused by high temperatures and also prevents high temperatures from affecting the reactivity and pH of the solvent.

[0056] In some embodiments, the oscillation frequency of the ultrasonic oscillator 150 is constant during the separation process of the blended fabric. For example, the oscillation frequency of the ultrasonic oscillator 150 can be fixed at 10 kHz, 20 kHz, 30 kHz, 40 kHz, or 50 kHz. By designing the oscillation frequency to a constant value, not only can a stable and consistent oscillation effect be provided, but the oscillation performance can also be more precisely controlled and optimized. Furthermore, the complexity of the system can be reduced, and the cost of frequent adjustments or calibrations can be eliminated, thereby increasing the service life of the equipment. In embodiments where the oscillation frequency is constant, a constant power can be output using voltage control to adjust the oscillation frequency, thus eliminating the need for the complex means of using piezoelectric elements to monitor the oscillation frequency. Moreover, it is worth noting that the ultrasonic oscillator 150 disclosed herein directly oscillates the solvent in the reaction tank 110 without the need for water-separated oscillation. This approach avoids the absorption or loss of oscillation energy by the aqueous medium, thereby improving energy transfer efficiency and making the oscillation effect more concentrated.

[0057] In some embodiments, the ultrasonic oscillator 150 is adjacent to the filter 140, meaning there are no other functional elements between the ultrasonic oscillator 150 and the filter 140. This prevents cellulose material from clogging the filter 140 due to deposition on its surface. Specifically, the continuous oscillation of the ultrasonic oscillator 150 can moderately agitate any cotton or cellulose material deposited on the surface of the filter 140, thereby accelerating the passage of solvent through the filter 140 into the return line 160. In some embodiments, the filter 140 may be located at the U-shaped bend of the reaction tank 110, and the number of ultrasonic oscillators 150 may be two. One ultrasonic oscillator 150 may be adjacently located at the upper right or upper left of the filter 140 (i.e., located on the U-shaped sidewall of the reaction tank 110), and the other ultrasonic oscillator 150 may be adjacently located at the lower left or lower right of the filter 140 (i.e., located at the U-shaped bottom of the reaction tank 110). In short, the two ultrasonic oscillators 150 are located at both ends of the filter screen diameter of the filter 140 (e.g., ...). Figure 1 (As shown). This design allows the filter 140 to be subjected to oscillating forces from multiple directions, thereby increasing the speed at which the solvent passes through the filter 140.

[0058] In some embodiments, the blades 132 of the blade-type stirrer 130 are positioned higher in the longitudinal direction D1 of the reaction tank 110 than the connection point P between the ultrasonic oscillator 150 and the reaction tank 110 (e.g., Figure 1(As shown). Through this design, the cavitation bubbles generated by the ultrasonic oscillator 150, after being formed, can be driven and transmitted to the top of the entire reaction tank 110 by the spin vortex generated by the blade agitator 130. In this way, the cavitation bubbles can not only act near the blade agitator 130 (for example, burst and generate sound pressure near the blade agitator 130), but can also be transmitted further upward, thereby helping to ensure that the entire blended fabric is affected by the cavitation bubbles, so as to improve the separation effect of the blended fabric.

[0059] In some embodiments, both the ultrasonic oscillator 150 and the blade agitator 130 are located at the bottom position B of the reaction tank 110, wherein the bottom position B of the reaction tank 110 falls within 0% to 50% (e.g., 10%, 20%, 30%, 40%) of the total height H of the reaction tank 110 in the longitudinal direction D1, and the vertical distance X between the top 132T of the blade 132 of the blade agitator 130 and the top 150T of the highest ultrasonic oscillator 150 is 0 mm (i.e., the top 132T of the blade 132 and the top 150T of the ultrasonic oscillator 150 are at the same height) and up to 200 mm. By placing both the ultrasonic oscillator 150 and the blade agitator 130 at the bottom position B of the reaction tank 110 and keeping them sufficiently close, the cavitation bubbles generated by the ultrasonic oscillator 150 can contact the spinning vortex generated by the blade agitator 130 before they break. Sufficient upper space is also provided so that the spinning vortex can carry the cavitation bubbles upwards and distribute them throughout the entire reaction tank 110. This helps increase the probability of cavitation bubbles contacting the blended fabric, thereby improving the separation effect of the blended fabric. Overall, the combination of the ultrasonic oscillator 150 and the blade agitator 130 combines spin shear force and oscillation force, allowing the solvent to penetrate evenly into the blended fabric, which helps to promote reaction equilibrium and achieve better separation results.

[0060] In some embodiments, the blended fabric separation device 100 may further include a pressure detector 180 and a pH detector 190. The pressure detector 180 is located in the return line 160 and configured to detect the pressure of the solvent in the return line 160 to determine whether to activate a backwashing device (not shown). The backwashing device may be connected to a filter 140 and configured to instantaneously introduce air at a certain pressure into the filter 140 via an air pump therein, thereby clearing the filter 140 and restoring its flowability, ensuring a stable overall circulation flow rate for the blended fabric separation device 100. The pH detector 190 is located in the return line 160 and configured to detect the pH value of the solvent in the return line 160 to ensure that the pH value of the recovered solvent remains within a reusable range. In some embodiments, when the pH detector 190 detects that the pH of the solvent in the reflux line 160 is less than 9.9, the control device (not shown) connected to the pH detector 190 can control the replenishment device (not shown) to add pH adjuster to the reaction tank 110 to ensure that the recovered solvent does not affect the overall reusability of the solvent.

[0061] In some embodiments, the separation device 100 for the blended fabric may further include a water level detector 200. The water level detector 200 is disposed in the reaction tank 110 and configured to monitor the solvent level (water level) in the reaction tank 110 to ensure the reaction continues. In some embodiments, when the water level detector 200 detects that the water level (e.g., the solvent level during the reaction) falls between 90% and 95% of the initial water level (e.g., the solvent level before the reaction began, i.e., the initial solvent level) and repeatedly rises and falls within this range, it indicates that the reaction continues; and when the water level detector 200 detects that the water level remains unchanged, it indicates that the reaction has terminated.

[0062] Please see Figure 2 This is a schematic flow diagram of a method for separating blended fabrics according to some embodiments of the present disclosure. The method for separating blended fabrics includes steps S10 to S50. In step S10, the blended fabric and solvent are placed in a reaction tank, and the blended fabric is reacted in the solvent to separate into polyester fabric and cellulose material. In step S20, at least one ultrasonic oscillator connected to the reaction tank is activated, and the ultrasonic oscillator provides an oscillation frequency of 10 kHz to 50 kHz. In step S30, after activating the ultrasonic oscillator, a blade stirrer located in the reaction tank is activated, wherein the blade stirrer rotates in at least two directions of rotation. In step S40, the cellulose material is collected using a filter located at the bottom of the reaction tank. In step S50, the solvent after reaction is returned to the reaction tank through a return line connecting the filter and the reaction tank. In the following description, the following will be described in conjunction with... Figure 1The steps described above for the separation device 100 for blended fabrics are explained in sequence. It should be understood that since the configuration and connection relationship of each component in the separation device 100 for blended fabrics have been explained above, they will not be repeated hereafter.

[0063] First, in step S10, the blended fabric and solvent are placed in reaction tank 110, allowing the blended fabric to react in the solvent to separate into polyester fabric and cellulose material. In some embodiments, the solvent may include 2,2,6,6-tetramethylpiperidine oxide (TEMPO), sodium bromide (NaBr), and sodium hypochlorite (NaClO) (hereinafter referred to as the TEMPO / NaBr / NaClO solvent system). Since the TEMPO / NaBr / NaClO solvent system can rapidly oxidize hydroxyl groups to carboxyl groups with minimal damage to cellulose and hemicellulose materials during oxidation, it can efficiently oxidize the cellulose material in the blended fabric into highly valuable micronized or nanocellulose, and, in conjunction with the operation of the blended fabric separation device 100, allow the cellulose material to be recovered. Furthermore, using the TEMPO / NaBr / NaClO solvent system also helps to maintain a high degree of structural integrity in the recovered polyester material; that is, the recovered polyester material can have the form of a complete fabric (polyester fabric). For example, when the blended fabric is in the form of scraps, the recycled polyester fabric is also in the form of scraps. As another example, when the blended fabric is in the form of rolls, the recycled polyester fabric can be in the form of rolls.

[0064] Next, in step S20, at least one ultrasonic oscillator 150 connected to the reaction tank 110 is activated, providing an oscillation frequency of 10 kHz to 50 kHz. Specifically, upon activation of the ultrasonic oscillator 150, multiple cavitation bubbles are generated in the solvent, with diameters ranging from 5 micrometers to 500 micrometers. As mentioned earlier, cavitation bubbles of suitable size increase the contact area between the blended fabric and the solvent, accelerating the reaction and allowing the cellulose material produced after the reaction to detach from the blended fabric via oscillation, thus enabling the solvent to quickly contact the unreacted cellulose material. Furthermore, cavitation bubbles of suitable size prevent the generation of excessive sound pressure during bursting, thereby preventing damage to the structure of the recycled polyester fabric. Additionally, cavitation bubbles of suitable size can transmit over a longer distance so that the blended fabric above the reaction tank 110 can also be affected by the cavitation bubbles. In some implementations, the ultrasonic oscillator 150 provides a constant oscillation frequency throughout the separation of the blended fabric. As mentioned above, designing the oscillation frequency to be constant not only provides a stable and consistent oscillation effect, but also allows for more precise control and optimization of oscillation performance. Furthermore, it reduces system complexity and eliminates the cost of frequent adjustments or calibrations, thereby extending the lifespan of the equipment.

[0065] Subsequently, in step S30, after starting the ultrasonic oscillator 150, the blade-type stirrer 130 located in the reaction tank 110 is started, causing the blade-type stirrer 130 to rotate. Specifically, when the blade-type stirrer 130 rotates, it can form a spin vortex in the solvent, and the cavitation bubbles formed in step S20 can be acted upon by the spin shear force of the spin vortex and propagated upwards with the spin vortex, simultaneously penetrating into the blended fabric. Furthermore, the blade-type stirrer 130 has at least two rotation directions. Specifically, when viewed from a top angle, the two rotation directions of the blade-type stirrer 130 can be clockwise and counterclockwise, that is, the blade-type stirrer 130 can rotate alternately in the clockwise and counterclockwise directions. As mentioned above, this alternating rotation method can construct a stirring pattern of forward / reverse rotation, continuously changing the direction of the spin vortex during the separation of the blended fabric (e.g., clockwise and counterclockwise spin vortices). This ensures that the blended fabric does not undergo unintended deformations such as folding, twisting, agglomeration, or layering due to continuous spin compression in the same direction. This ensures that the solvent can uniformly and fully impregnate the blended fabric, preventing the solvent from reacting only in specific areas or surfaces of the blended fabric. In a preferred embodiment, the blade-type stirrer 130 can first rotate clockwise for a first time (step 1), then rotate counterclockwise for a second time (step 2), and repeat steps 1-2. The first and second times can be the same (e.g., both 3 minutes, both 4 minutes, or both 5 minutes) to further reduce the probability of blended fabric entanglement, thereby reducing the possibility of deformation and allowing the solvent to impregnate the blended fabric more uniformly.

[0066] It is worth noting that in this disclosure, the ultrasonic oscillator 150 is turned on first, followed by the blade agitator 130. This sequence ensures that cavitation bubbles can reliably enter the spin vortex and be guided into the blended fabric. Specifically, if the blade agitator 130 is turned on first to generate the spin vortex, the spin vortex will form a barrier due to its spin inertia, preventing the cavitation bubbles generated when the ultrasonic oscillator 150 is turned on subsequently from entering the spin vortex and thus from being transmitted upwards to the reaction tank 110 with the rotation of the spin vortex. In other words, this disclosure requires generating cavitation bubbles in the solvent before loading the spin vortex. It should be noted that since steps S10 to S30 are performed sequentially with short intervals between steps, it can be considered that the blended fabric and solvent only begin to react after the ultrasonic oscillator 150 and the blade stirrer 130 are started sequentially. In other words, the ultrasonic oscillator 150 and the blade stirrer 130 participate in the reaction throughout the entire process, and both are turned on continuously during the reaction. Overall, as the blended fabric and solvent continue to react, and with the spin vortex introducing cavitation bubbles into the blended fabric and generating sound pressure upon bursting, the cotton fibers and cellulose materials generated after the reaction can be detached from the polyester fabric through vibration.

[0067] Next, in step S40, the cellulose material is collected using a filter 140 located at the bottom B of the reaction tank 110. Specifically, the cotton fibers and cellulose material detached by the vibration settle towards the bottom of the reaction tank 110, falling into the filter 140 located at the bottom B of the reaction tank 110, thereby filtering out the solvent and collecting the cellulose material. As mentioned above, in some embodiments, the cotton fibers and cellulose material can sequentially pass through the coarse, medium, and fine filter layers in the filter 140 to achieve a more comprehensive filtration effect. In some embodiments, step S40 can be performed while the ultrasonic oscillator 150 and the blade agitator 130 are continuously operating. The vibration force of the ultrasonic oscillator 150 and the forward / reverse spin shear force of the blade agitator 130 help to ensure uniform settling of the cotton fibers and cellulose material and prevent the filter 140 from becoming clogged due to deposition of the cotton fibers and cellulose material on its surface.

[0068] Subsequently, in step S50, the reacted solvent is returned to the reaction tank 110 via a return line 160 connecting the filter 140 and the reaction tank 110. Specifically, the solvent filtered by the filter 140 can enter the return line 160 and be returned to the reaction tank 110 for reuse. In some embodiments, as the solvent passes through the return line 160, a pressure detector 180 and a pH detector 190 located in the return line 160 can detect the solvent's pressure and pH value, and perform corresponding actions based on the detection results (see above for details). In some embodiments, throughout the separation of the blended fabric, a level detector 200 continuously monitors the solvent level in the reaction tank 110 to ensure the reaction continues (see above for details).

[0069] In some embodiments, after step S50 is completed, steps S20 to S50 can be repeated sequentially until the reaction terminates. In some embodiments, after the reaction terminates, the solvent after the reaction can be discharged from the reaction tank 110 before the multi-cylindrical tank 120 located in the reaction tank 110 is started to remove excess solvent remaining on the polyester fabric. Specifically, the multi-cylindrical tank 120 disclosed herein is configured to start and rotate only after the blended fabric and solvent have reacted completely, so that the blended fabric achieves the effect of dehydration. In addition, depending on the type of blended fabric, it can be determined whether the blade agitator 130 operates (rotates) simultaneously during the operation (rotation) of the multi-cylindrical tank 120. For example, when the blended fabric is in the form of scraps, the blade agitator 130 can be designed to rotate in the opposite direction while the multi-cylinder tank 120 rotates (e.g., the multi-cylinder tank 120 rotates clockwise while the blade agitator 130 rotates counterclockwise; or the multi-cylinder tank 120 rotates counterclockwise while the blade agitator 130 rotates clockwise). This reverse rotation dewatering method helps to improve the dewatering speed and effect of the scraps. As another example, when the blended fabric is in the form of a whole roll, the blade agitator 130 can remain stationary while the multi-cylinder tank 120 rotates to prevent the fabric from tangling or knotting.

[0070] After completing the above steps, the polyester fabric can be taken out from the reaction tank 110 and the cellulose material can be taken out from the filter 140. The polyester fabric and cellulose material can be recycled and reused.

[0071] In the following description, various embodiments and comparative examples will be provided to demonstrate the effectiveness of this disclosure through various tests and evaluations. It should be understood that this disclosure should not be interpreted as limiting by the embodiments described below.

[0072] <Experimental Example 1>

[0073] The blended fabrics in the embodiments listed in Table 1 are separated using the blended fabric separation equipment and method described above. Each embodiment's blended fabric contains 65 wt% tertrol and 35 wt% cotton (T / C blended fabric). The reaction tank is a U-shaped mixing tank; the multi-cylinder tank is equipped with a cage-type agitator and is positioned in the center of the reaction tank; a blade-type agitator is positioned in the center of the reaction tank and surrounded by the cage-type agitator; the filter is a 400-mesh filter; there are two ultrasonic oscillators, and their distribution positions are as follows... Figure 1As shown; the blades of the blade-type stirrer are positioned higher than the connection point between the ultrasonic oscillator and the reaction tank. Both the ultrasonic oscillator and the blade-type stirrer are located at the bottom of the reaction tank, and the vertical distance between the top of the blades of the blade-type stirrer and the top of the highest ultrasonic oscillator is 46 mm. The separation equipment for the blended fabric also includes a pressure detector, a pH detector, and a water level detector. In step S10, the solvent is a TEMPO / NaBr / NaClO solvent system. In step S20, the oscillation frequency of the ultrasonic oscillator is 40 kHz (fixed value). In step S30, the blade-type stirrer rotates alternately clockwise and counterclockwise for 3 minutes each, at a speed of 120 rev / min. Step S40 is carried out while the ultrasonic oscillator and the blade-type stirrer are continuously operating. In step S50, the pH detector controls the pH of the solvent between 9.9 and 10.1. After the reaction is terminated, the solvent is drained, and the multi-cylindrical tank is rotated clockwise, while the blade-type stirrer is kept stationary.

[0074] The separation equipment used in the blended fabrics of the comparative examples in Table 1 is the same as that used in the blended fabrics of the embodiments, and the materials of the blended fabrics of the comparative examples are the same as those of the blended fabrics of the embodiments. The only difference between the separation methods used in the blended fabrics of the comparative examples and those used in the blended fabrics of the embodiments is whether or not the ultrasonic oscillator is turned on throughout the reaction.

[0075] Table 1

[0076]

[0077] Note: In Example 3, the ultrasonic oscillator was turned on and oscillated for 1 hour before the separation equipment for the blended fabric started operating (before the blended fabric and the solvent started to react).

[0078] After the separation of the blended fabrics was completed, the dissolution rate of the blended fabrics of each comparative example and each embodiment was measured, and the results are shown in Table 2.

[0079] Table 2

[0080]

[0081]

[0082] Note: Dissolution rate (%) = (weight of cloth before reaction - weight of cloth after reaction) / (0.35 × weight of cloth before reaction).

[0083] Based on the results of Example 1 and Comparative Examples 1-2, under the same reaction time (separation equipment operation time), the dissolution rate increases with increasing oscillation time, and the dissolution rate increases significantly when the ultrasonic oscillator is turned on throughout the reaction. Furthermore, as seen in Comparative Examples 1-2, the "stirring before oscillation" approach makes it difficult for cavitation bubbles to enter the spin vortex, resulting in a low dissolution rate. Similarly, the results of Comparative Examples 3-5 and 6-8 also show that the "stirring before oscillation" approach leads to a low dissolution rate. In contrast, the results of Example 2 and Comparative Examples 6-8 show that the dissolution rate is relatively improved when the ultrasonic oscillator is turned on throughout the reaction. Furthermore, the results of Example 1 and Example 3 show that turning on the ultrasonic oscillator beforehand does not affect the dissolution rate.

[0084] <Experimental Example 2>

[0085] The blended fabrics of the embodiments and comparative examples in Table 3 were separated using the blended fabric separation equipment and method described above. The blended fabrics of each embodiment and comparative example comprise 80 wt% tertrol and 20 wt% cotton (T / C blended fabric). The details of the blended fabric separation equipment are the same as in Examples 1-3. The details of the blended fabric separation method are the same as in Examples 1-3, the only difference being the oscillation frequency of the ultrasonic oscillator in step S20.

[0086] Table 3

[0087]

[0088] After the separation of the blended fabrics was completed, the dissolution rate of the blended fabrics of each comparative example and each embodiment was measured, and the results are shown in Table 4.

[0089] Table 4

[0090]

[0091] Note: Dissolution rate (%) = (weight of cloth before reaction - weight of cloth after reaction) / (0.20 × weight of cloth before reaction).

[0092] The results of Examples 4-6 show that when the oscillation frequency is in the range of 10 kHz to 40 kHz, the dissolution rate is at least 97%, with excellent dissolution effect achieved at an oscillation frequency of 40 kHz. The results of Comparative Example 9 show that when the ultrasonic oscillator is not turned on (the oscillation frequency of the ultrasonic oscillator is 0), the dissolution rate is only 89%.

[0093] <Experimental Example 3>

[0094] The blended fabrics of the embodiments and comparative examples in Table 5 were separated using the blended fabric separation equipment and method described above. Each embodiment and comparative example's blended fabric contained 80 wt% tertrol and 20 wt% cotton (T / C blended fabric). The details of the blended fabric separation equipment were the same as in Examples 1-3. The details of the blended fabric separation method were also the same as in Examples 1-3, except that during the entire reaction, after the pH value detector monitored the solvent's pH value, no pH adjuster was added based on the monitoring results. Instead, the reaction termination was determined by monitoring the solvent's pH value (the reaction was considered terminated when the solvent's pH value reached 7.5). The blended fabrics of each embodiment and comparative example in Table 5 weighed 2 kg. In each embodiment, the ultrasonic oscillator was turned on throughout the reaction, while in the comparative examples, the ultrasonic oscillator was not turned on throughout the reaction.

[0095] Table 5

[0096]

[0097] In this experimental example, the blended fabrics of each comparative example and each embodiment in Table 5 were separated, and the pH value of the solvent was monitored over time, and the dissolution rate of each comparative example and each embodiment was measured accordingly. Results Figure 3A and Figure 3B As shown, where Figure 3A The graphs show the pH value versus time relationship for Examples 7-9 and Comparative Example 10. Figure 3B The graph shows the dissolution rate versus time for Examples 7-9 and Comparative Example 10. Figure 3A As shown, the reaction terminates when the pH of the solvent is 7.5. Figure 3B As shown, a better dissolution effect can be achieved when the oscillation frequency is 40 kHz.

[0098] Although the present disclosure has been described above with reference to embodiments, it is not intended to limit the present disclosure. Any person skilled in the art may make various modifications and refinements without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be determined by the appended claims.

Claims

1. An apparatus for separating a blended fabric, characterized by comprising: comprising: a reaction tank; a multi-cylinder tank disposed in the reaction tank; a blade-type agitator disposed in the multi-cylinder tank, wherein the blade-type agitator has at least two rotation directions; a filter disposed at a bottom position of the reaction tank; at least one ultrasonic oscillator connected to the reaction tank, wherein the ultrasonic oscillator has an oscillation frequency of 10 kHz to 50 kHz; and a reflux line connecting the filter and the reaction tank.

2. The apparatus according to claim 1, wherein The ultrasonic oscillator is adjacent to the filter.

3. The apparatus according to claim 1, wherein A blade position of the blade-type agitator is higher than a connection position of the ultrasonic oscillator and the reaction tank.

4. The apparatus according to claim 1, wherein The ultrasonic oscillator and the blade-type agitator are disposed at the bottom position of the reaction tank, and the bottom position of the reaction tank falls within 0% to 50% of a total height of the reaction tank.

5. The apparatus according to claim 1, wherein The oscillation frequency of the ultrasonic oscillator is a constant value.

6. A method of separating a blended fabric, characterized by, comprising: placing a blended fabric and a solvent into a reaction tank to react the blended fabric in the solvent to separate into a polyester fabric and a cellulose material; starting at least one ultrasonic oscillator connected to the reaction tank to make the ultrasonic oscillator provide an oscillation frequency of 10 kHz to 50 kHz; after starting the ultrasonic oscillator, starting a blade-type agitator located in the reaction tank, wherein the blade-type agitator rotates in at least two rotation directions; collecting the cellulose material using a filter located at a bottom position of the reaction tank; and making the solvent after the reaction pass through a reflux line connecting the filter and the reaction tank to reflux the solvent into the reaction tank.

7. The method of separating a blended fabric according to claim 6, wherein The ultrasonic oscillator generates a plurality of cavitation bubbles in the solvent, and a diameter of the plurality of cavitation bubbles is 5 μm to 500 μm.

8. The method of claim 6, wherein the blend fabric is a woven fabric. The blade-type agitator repeatedly performs the following steps: rotating in a clockwise direction for a first time; and rotating in a counterclockwise direction for a second time, wherein the first time and the second time are the same.

9. The method of claim 6, wherein the blend fabric is a woven fabric. The oscillation frequency provided by the ultrasonic oscillator is a constant value.

10. The method of claim 6, wherein the blend fabric is a woven fabric. further comprising: after the solvent after the reaction is discharged from the reaction tank, starting a multi-cylinder tank located in the reaction tank to remove excess solvent remaining on the polyester fabric.

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