Separation and recovery method of blended fabric and application of separation and recovery method

Abstract

The invention discloses a separation and recovery method of blended fabric and application thereof, and relates to the field of resource recycling and textile green low-carbon hot spots. The separation and recovery method of the blended fabric comprises the following steps: (1) acquiring component information of the blended fabric to be treated by adopting a differential time domain laser Raman spectroscopy; (2) spraying a metal ion solution on the surface of the blended fabric; (3) carrying out rolling and ultrasonic treatment on the blended fabric treated in the step (2) to enable the blended fabric to uniformly absorb moisture; (4) separating the blended fabric into single yarns, and cutting the single yarns to obtain mixed yarn fragments; and (5) placing the mixed yarn segments in an electric field, and separating the yarn segments with different components under the action of electric field force. The separation and recovery method is low in cost, high in efficiency, green and environment-friendly, and realizes high-added-value recovery and reutilization of the blended fabric.

Description

Technical Field

[0001] The invention relates to the hot fields of resource recycling and green and low-carbon textile production, and in particular to a method for separating and recovering blended fabrics and an application thereof. Background Art

[0002] At present, there are three main ways to recycle waste textiles: first, sort, clean, and disinfect waste textiles, and then continue to circulate them for their original purpose, such as selling them as second-hand goods at a low price; second, recycle and regenerate them, including physical and chemical methods; and third, incinerate and landfill. Among them, the recycling and reuse of blended fabrics is mainly through chemical dissolution, which has high recycling costs and great technical difficulties, and the use of chemical reagents is not environmentally friendly.

[0003] Therefore, it is necessary to develop a method for recycling and reusing blended fabrics that is low in cost, low in technical difficulty, and environmentally friendly. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a method for separating and recycling blended fabrics, which is low in cost, low in technical difficulty, environmentally friendly, and can achieve high added value recycling of blended fabrics.

[0005] The invention also provides application of the separation and recovery method in recycling blended fabrics.

[0006] A method for separating and recovering a blended fabric according to a first aspect of the present invention comprises the following steps: (1) Using differential time-domain laser Raman spectroscopy to obtain the composition information of the blended fabric to be processed; (2) spraying a metal ion solution onto the surface of the blended fabric; (3) rolling and ultrasonically treating the blended fabric treated in step (2) to make the blended fabric absorb moisture uniformly; (4) separating the blended fabric into individual yarns and cutting them into short pieces to obtain blended yarn segments; (5) Placing the mixed yarn fragments in an electric field, and separating the yarn fragments with different components under the action of the electric field force.

[0007] The separation and recovery method according to the embodiment of the present invention has at least the following beneficial effects: The separation and recovery method of the embodiment has simple process, low operation difficulty, low cost, environmental friendliness, and uses less chemical reagents. The separation efficiency of the yarn of the separation and recovery method reaches more than 97%, and the separation purity reaches more than 95%, and can be directly applied to the recovery of the single-component yarn produced, so as to realize the high added value recovery and utilization of the blended fabric.

[0008] According to some embodiments of the present invention, the blended fabric is a fabric formed by twisting two or more fiber yarns of different components into a blended fabric.

[0009] According to some embodiments of the present invention, the blended fabric is a blended fabric of synthetic fiber yarn and natural fiber yarn; or a blended fabric of synthetic fiber yarn and regenerated fiber yarn; or a blended fabric of synthetic fiber yarn and synthetic fiber yarn; or a blended fabric of natural fiber yarn and natural fiber yarn.

[0010] According to some embodiments of the present invention, the natural fiber yarn includes at least one of cotton yarn, silk yarn, wool yarn, and linen yarn.

[0011] According to some embodiments of the present invention, the synthetic fiber includes at least one of polyester yarn, nylon yarn, acrylic yarn, vinylon yarn, chloroprene yarn, and spandex yarn.

[0012] According to some embodiments of the present invention, the regenerated fiber includes at least one of viscose yarn and modal yarn.

[0013] According to some embodiments of the present invention, the blended fabric includes at least one of a blended fabric of polyester yarn and cotton yarn, a blended fabric of nylon yarn and cotton yarn, a blended fabric of polyester yarn and nylon yarn, a blended fabric of cotton yarn and acrylic yarn, a blended fabric of cotton yarn and spandex yarn, a blended fabric of polyester yarn and acrylic yarn, a blended fabric of nylon yarn and acrylic yarn, a blended fabric of viscose fiber yarn and polyester yarn, a blended fabric of viscose fiber yarn and nylon yarn, a blended fabric of viscose fiber yarn and acrylic yarn, a blended fabric of cotton yarn and linen yarn, a blended fabric of cotton yarn and wool yarn, a blended fabric of cotton yarn and modal yarn, and a blended fabric of cotton yarn, polyester yarn and nylon yarn.

[0014] According to some embodiments of the present invention, the ingredient information includes ingredient composition and content thereof.

[0015] According to some embodiments of the present invention, the metal ion solution is the metal ion aqueous solution.

[0016] According to some embodiments of the present invention, the metal ions in the metal ion solution include K + 、Na + , Ca 2+ Mg 2+ At least one of .

[0017] According to some embodiments of the present invention, the K + The source includes at least one of KCl, KBr, K2SO4, and KNO3.

[0018] According to some embodiments of the present invention, the Na + The source includes at least one of NaCl, Na2SO4, and NaNO3.

[0019] According to some embodiments of the present invention, the Ca 2+ The source includes at least one of CaCl2 and Ca(NO3)2.

[0020] According to some embodiments of the present invention, the Mg 2+ The source includes at least one of MgCl2 and MgSO4.

[0021] According to some embodiments of the present invention, in the metal ion solution, the concentration of metal ions is 0.5 mol / L~15.5 mol / L. For example: it can be 0.5 mol / L, 1 mol / L, 1.5 mol / L, 2 mol / L, 2.5 mol / L, 3 mol / L, 3.5 mol / L, 4 mol / L, 4.5 mol / L, 5 mol / L, 5.5 mol / L, 6 mol / L, 6.5 mol / L, 7 mol / L, 7.5mol / L, 8 mol / L, 8.5 mol / L, 9 mol / L, 9.5 mol / L, 10 mol / L, 10.5 mol / L, 11 mol / L, 11.5mol / L, 12 mol / L, 12.5 mol / L, 13 mol / L, 13.5 mol / L, 14 mol / L, 14.5 mol / L, 15 mol / L or 15.5 mol / L.

[0022] According to some embodiments of the present invention, the blended fabric is composed of synthetic fiber yarn (such as nylon yarn or polyester yarn) and natural fiber yarn (such as cotton yarn) in a mass ratio of 1:0.9~1.1; the concentration of metal ions in the metal ion solution is 1 mol / L~1.5 mol / L (for example: it can be 1 mol / L, 1.05 mol / L, 1.1 mol / L, 1.15 mol / L, 1.2 mol / L, 1.25 mol / L, 1.3 mol / L, 1.35 mol / L, 1.4 mol / L, 1.45 mol / L or 1.5 mol / L).

[0023] According to some embodiments of the present invention, the blended fabric is composed of two synthetic fiber yarns (such as nylon yarn and polyester yarn) with a mass ratio of 1:0.9~1.1; the diameters of the two synthetic fiber yarns are different. The concentration of metal ions in the metal ion solution is 8 mol / L~9.5 mol / L (for example, it can be 8 mol / L, 8.1 mol / L, 8.2 mol / L, 8.3 mol / L, 8.4 mol / L, 8.5 mol / L, 8.6 mol / L, 8.7 mol / L, 8.8 mol / L, 8.9 mol / L, 9mol / L, 9.1 mol / L, 9.2 mol / L, 9.3 mol / L, 9.4 mol / L or 9.5 mol / L).

[0024] According to some embodiments of the present invention, the blended fabric is composed of natural fiber yarn (such as cotton yarn) and mixed synthetic fiber yarn in a mass ratio of 1: (8.5~9.5) (the diameters of the mixed synthetic fiber yarns are different. For example, the mixed synthetic fiber yarn is composed of nylon yarn and polyester yarn; the mass ratio of nylon yarn to polyester yarn can be (1.8~2.2): 1). The concentration of metal ions in the metal ion solution is 8 mol / L to 9.5 mol / L (for example, 8 mol / L, 8.1 mol / L, 8.2 mol / L, 8.3 mol / L, 8.4 mol / L, 8.5 mol / L, 8.6 mol / L, 8.7 mol / L, 8.8 mol / L, 8.9 mol / L, 9 mol / L, 9.1 mol / L, 9.2 mol / L, 9.3 mol / L, 9.4 mol / L or 9.5 mol / L).

[0025] According to some embodiments of the present invention, in step (2), the blended fabric surface needs to be sprayed at least until water mist appears.

[0026] According to some embodiments of the present invention, the ultrasonic power of the ultrasonic treatment is 20 kHz to 60 kHz. For example, it can be 20 kHz, 22 kHz, 24 kHz, 26 kHz, 28 kHz, 30 kHz, 32 kHz, 34 kHz, 36 kHz, 38 kHz, 40 kHz, 42 kHz, 44 kHz, 46 kHz, 48 kHz, 50 kHz, 52 kHz, 54 kHz, 56 kHz, 58 kHz or 60 kHz.

[0027] According to some embodiments of the present invention, the ultrasonic treatment has an ultrasonic time of 1 s to 30 s. For example, it may be 1 s, 2 s, 4 s, 6 s, 8 s, 10 s, 12 s, 14 s, 16 s, 18 s, 20 s, 22 s, 24 s, 26 s, 28 s or 30 s.

[0028] According to some embodiments of the present invention, the mass volume ratio of the blended fabric to the metal ion solution is not less than 1 g:50 mL.

[0029] According to some embodiments of the present invention, the mass volume ratio of the blended fabric to the metal ion solution is 1 g: 1 to 50 mL. For example, it can be 1 g: 1 mL, 1 g: 5 mL, 1 g: 10 mL, 1 g: 15 mL, 1 g: 20 mL, 1 g: 25 mL, 1 g: 30 mL, 1 g: 35 mL, 1 g: 40 mL, 1 g: 45 mL or 1 g: 50 mL.

[0030] According to some embodiments of the present invention, in step (4), the length of the yarn is 1 mm to 50 mm. For example, it can be 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm or 50 mm.

[0031] According to some embodiments of the present invention, in step (5), the hybrid yarn segment is placed on a positive electrode plate.

[0032] According to some embodiments of the present invention, in step (5), the number of layers of the mixed yarn segments laid on the positive electrode plate is 1.

[0033] According to some embodiments of the present invention, in step (5), the electric field is a direct current electric field.

[0034] According to some embodiments of the present invention, in step (5), the distance between the two electrodes of the electric field is 1 cm to 10 cm. For example, it can be 1 cm, 1.5 cm, 2 cm, 2.5 cm, 3 cm, 3.5 cm, 4 cm, 4.5 cm, 5 cm, 5.5 cm, 6 cm, 6.5 cm, 7 cm, 7.5 cm, 8 cm, 8.5 cm, 9 cm, 9.5 cm or 10 cm.

[0035] According to some embodiments of the present invention, in step (5), the voltage of the electric field is 10 kV to 100 kV. For example, it can be 10 kV, 15 kV, 20 kV, 25 kV, 30 kV, 35 kV, 40 kV, 45 kV, 50 kV, 55 kV, 60 kV, 65 kV, 70 kV, 75 kV, 80 kV, 85 kV, 90 kV, 95 kV or 100 kV.

[0036] According to some embodiments of the present invention, in step (4), the electric field is applied for a duration of 2 s to 30 s. For example, the duration may be 2 s, 3 s, 4 s, 5 s, 6 s, 7 s, 8 s, 9 s, 10 s, 12 s, 14 s, 16 s, 18 s, 20 s, 22 s, 24 s, 26 s, 28 s or 30 s.

[0037] According to some embodiments of the present invention, if the hybrid yarn segment is composed of a synthetic fiber yarn segment and a natural fiber yarn segment, the distance between the two electrodes of the electric field is 5 cm to 10 cm, the voltage of the electric field is 20 kV to 55 kV, and the power-on time of the electric field is 3 s to 7 s.

[0038] According to some embodiments of the present invention, if the mixed yarn segment is composed of different synthetic fiber yarn segments with different diameters, the distance between the two electrodes of the electric field is 4 cm~6 cm, the voltage of the electric field is 25 kV~35 kV, and the power-on time of the electric field is 1 s~5 s.

[0039] According to some embodiments of the present invention, the separation and recovery method also includes post-recovery reuse processing.

[0040] According to some embodiments of the present invention, the recycling and reuse process includes: processing the separated yarns. One way is to directly compress and pack them as raw materials for making other products (such as for electrostatic flocking), and another way is to use reagents to dissolve or melt them and re-spin them.

[0041] According to the second aspect of the present invention, the separation and recovery method described in the first aspect of the present invention is applied to the recycling of blended fabrics.

[0042] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 It is a schematic flow chart of a method for separating and recovering a blended fabric of the present invention. DETAILED DESCRIPTION

[0044] The following will be combined with the embodiments to clearly and completely describe the concept of the present invention and the technical effects produced, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0045] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0046] When a numerical range is disclosed herein, the above range is considered to be continuous and includes the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0047] The term "not less than" means greater than or equal to, and should be understood to include the number itself.

[0048] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0049] Take blended fabric samples with different components, collect differential time-domain Raman spectral information of a large number of blended fabric samples, use airPLS to subtract the spectral background information, remove the fluorescence effect, and then use wavelet function to further process the spectrum. Use principal component analysis to compare before and after processing to establish a differential time-domain Raman spectral model. The differential time-domain Raman spectral model can classify and identify the components and contents of blended fabrics through laser Raman spectroscopy. Those skilled in the art can also obtain the component composition information of blended fabrics through other well-known methods.

[0050] The present invention uses a metal ion solution to treat the blended fabric, and uses metal ions to strengthen the motion state of the yarn in the electric field. There are upper and lower electrode plates in the DC electric field (the lower electrode plate is the positive electrode plate), and the disassembled mixed yarn is evenly spread on the positive electrode plate. The distance between the upper and lower electrodes, the voltage and the power-on time are appropriately adjusted. The yarn with better conductivity can quickly rise to the upper negative electrode plate in large quantities, while the fiber with poor conductivity will remain in its original state. The polarization, take-off and flight speeds of yarns with different components are different, thereby achieving the separation of the mixed yarn.

[0051] (1) If the microscopic surface structures of different fiber yarns in the blended fabric are significantly different (e.g., the surface of cotton yarn is rough and has grooves, while the surface of nylon yarn is smooth), the metal ion concentration of the metal ion solution should be selected according to the mass percentage of the fiber yarn with relatively rough surface. The higher the mass percentage of the fiber yarn with relatively rough surface, the lower the metal ion concentration of the metal ion solution; the lower the mass percentage of the fiber yarn with relatively rough surface, the higher the metal ion concentration of the metal ion solution. The electric field force on the fiber yarn with relatively rough surface is greater than that on the fiber yarn with relatively smooth surface, and it is easier to fly.

[0052] (2) If the microscopic surface structure difference between different fiber yarns in the blended fabric is small (for example, the yarn obtained by twisting polyester yarn and nylon yarn, the surface of polyester and nylon are both smooth, but the nylon yarn is finer and the polyester yarn is thicker), then use a high concentration of metal ion solution for treatment. The larger the diameter of the fiber yarn, the larger the metal ion coverage area, the greater the electric field force it is subjected to, and the easier it is to fly.

[0053] Example 1 This example provides a method for separating and recovering blended fabrics, and the schematic flow chart is as follows: Figure 1 The steps are as follows: (1) Identification of the type and content of blended fabrics (qualitative and quantitative identification): The treated blended fabrics were scanned by differential time-domain laser Raman spectroscopy and identified using the established differential time-domain Raman spectroscopy model.

[0054] It was determined that the blended fabric consisted of 50wt% nylon yarn and 50wt% cotton yarn.

[0055] (2) Take 0.1 g of the blended fabric and spray 5 mL of 1.37 mol / L NaCl aqueous solution until water mist appears on the surface of the blended fabric.

[0056] (3) The blended fabric treated in step (2) is rolled to allow the blended fabric to absorb moisture evenly, and then subjected to ultrasonic treatment (ultrasonic power of 40 kHz and ultrasonic time of 10 s).

[0057] (4) Disassembly and processing: After the blended fabric is hardened, it is shredded and disassembled into single yarns with a length of 3 mm.

[0058] (5) Separation: The distance between the upper and lower electrode plates (the lower electrode plate is the positive plate) was adjusted to 5 cm, the DC voltage was 55 kV, and the power-on time was 3 s. Under the action of the electric field force, the cotton yarn quickly polarized and flew up to the upper recovery plate, while the nylon yarn that had not yet flown up was on the lower electrode plate.

[0059] (6) Recycling: The separated nylon yarn and cotton yarn were collected and tested, and the recovery rate of nylon reached 99.3% and the purity reached 99%; the recovery rate of cotton yarn reached 98.6% and the purity reached 99.3%.

[0060] The recycled cotton yarn is dissolved with chemical reagents and re-spun; the recycled nylon yarn is melted, granulated and spun to obtain regenerated nylon fiber.

[0061] Example 2 This example provides a method for separating and recovering blended fabrics, and the steps are as follows: (1) Identification of the types and contents of blended fabrics: The treated blended fabrics were scanned by differential time-domain laser Raman spectroscopy and identified using the established differential time-domain Raman spectroscopy model.

[0062] It was determined that the blended fabric consisted of 50wt% polyester yarn and 50wt% cotton yarn.

[0063] (2) Take 0.1 g of the blended fabric and spray 5 mL of 1.37 mol / L NaCl aqueous solution until water mist appears on the surface of the blended fabric.

[0064] (3) The blended fabric treated in step (2) is rolled to allow the blended fabric to absorb moisture evenly, and then subjected to ultrasonic treatment (ultrasonic power of 40 kHz and ultrasonic time of 10 s).

[0065] (4) Disassembly and processing: After the blended fabric is hardened, it is shredded and disassembled into single yarns with a length of 3 mm to obtain blended yarn segments.

[0066] (5) Separation: The distance between the upper and lower electrode plates (the lower electrode plate is the positive plate) was adjusted to 10 cm, the DC voltage was 45 kV, and the power-on time was 7 s. The mixed yarn fragment was placed on the lower electrode plate. Under the action of the electric field force, the cotton yarn was rapidly polarized and flew up to the upper recovery plate, while the polyester yarn that had not yet flown up was on the lower electrode plate.

[0067] (6) Recycling: The separated polyester yarn and cotton yarn were collected and tested to have a polyester recovery rate of 99.4% and a purity of 97.84%; the cotton yarn recovery rate was 97.98% and a purity of 99.4%.

[0068] The recycled cotton yarn is compressed and packaged and used as raw materials for other products, such as electrostatic flocking; the recycled polyester yarn is melted, granulated and spun to obtain polyester fiber.

[0069] Example 3 This example provides a method for separating and recovering blended fabrics, and the steps are as follows: (1) Identification of the types and contents of blended fabrics: The treated blended fabrics were scanned by differential time-domain laser Raman spectroscopy and identified using the established differential time-domain Raman spectroscopy model.

[0070] It was determined that the blended fabric consisted of 50wt% polyester yarn and 50wt% nylon yarn.

[0071] (2) Take 0.1 g of the blended fabric and spray 5 mL of 8.56 mol / L NaCl aqueous solution until water mist appears on the surface of the blended fabric.

[0072] (3) The blended fabric treated in step (2) is rolled to allow the blended fabric to absorb moisture evenly, and then subjected to ultrasonic treatment (ultrasonic power of 40 kHz and ultrasonic time of 10 s).

[0073] (4) Disassembly and processing: After the blended fabric is hardened, it is shredded and disassembled into single yarns with a length of 3 mm.

[0074] (5) Separation: The distance between the upper and lower electrode plates (the lower electrode plate is the positive plate) was adjusted to 5 cm, the DC voltage was 30 kV, and the power-on time was 3 s. Under the action of the electric field force, the polyester yarn quickly polarized and flew up to the upper recovery plate, while the nylon yarn that had not yet flown up was on the lower electrode plate.

[0075] (6) Recycling: The separated polyester yarn and nylon yarn were collected and tested to have a polyester recovery rate of 97.8% and a purity of 95.94%; the nylon yarn recovery rate of 98.4% and a purity of 97.81%.

[0076] The recycled nylon yarn is melted, granulated and spun to obtain regenerated nylon fiber; the recycled polyester yarn is used as raw material and crushed for the production of electrostatic flocking products.

[0077] Example 4 This example provides a method for separating and recovering blended fabrics, and the steps are as follows: (1) Identification of the types and contents of blended fabrics: The treated blended fabrics were scanned by differential time-domain laser Raman spectroscopy and identified using the established differential time-domain Raman spectroscopy model.

[0078] It has been determined that the blended fabric is composed of 60wt% cotton yarn, 30wt% polyester yarn and 10wt% nylon yarn.

[0079] (2) Take 0.1 g of the blended fabric and spray 5 mL of 8.56 mol / L NaCl aqueous solution until water mist appears on the surface of the blended fabric.

[0080] (3) The blended fabric treated in step (2) is rolled to allow the blended fabric to absorb moisture evenly, and then subjected to ultrasonic treatment (ultrasonic power of 40 kHz and ultrasonic time of 10 s).

[0081] (4) Disassembly and processing: After the blended fabric is hardened, it is shredded and disassembled into single yarns with a length of 3 mm.

[0082] (5) Separation: The distance between the upper and lower electrode plates (the lower electrode plate is the positive plate) was adjusted to 5 cm, the DC voltage was 20 kV, and the power-on time was 3 s. Under the action of the electric field force, the cotton yarn quickly polarized and flew up to the upper recovery plate, and the polyester yarn and nylon yarn that had not yet flown up were on the lower electrode plate. After the cotton yarn was cleaned and recycled, the power was turned on again, the DC voltage was 30 kV, and the power-on time was 3 s. Under the action of the electric field force, the polyester yarn quickly polarized and flew up to the upper recovery plate, and the nylon yarn that had not yet flown up was on the lower electrode plate.

[0083] (6) Recycling: The separated cotton yarn, polyester yarn and nylon yarn were collected and tested. The recovery rate of cotton reached 97.83% and the purity reached 98.32%, the recovery rate of polyester reached 95.33% and the purity reached 99.65%, and the recovery rate of nylon yarn reached 99% and the purity reached 96.11%.

[0084] The recycled cotton yarn is compressed and packaged and used as raw materials for other products. The nylon yarn is melted, granulated and spun to obtain regenerated nylon fiber. The recycled polyester yarn is used as raw material and crushed for the production of electrostatic flocking products.

[0085] The embodiments of the present invention are described in detail above in conjunction with the embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A method for separating and recovering blended fabrics, characterized in that: The following steps are involved: (1) Differential time-domain laser Raman spectroscopy is used to obtain the composition information of the blended fabric to be processed; (2) spraying a metal ion solution onto the surface of the blended fabric; (3) rolling and ultrasonically treating the blended fabric treated in step (2) to make the blended fabric absorb moisture uniformly; (4) separating the blended fabric into individual yarns and cutting them into short pieces to obtain blended yarn segments; (5) Placing the mixed yarn fragments in an electric field, and separating the yarn fragments with different components under the action of the electric field force.

2. The separation and recovery method according to claim 1, characterized in that: The blended fabric is a blended fabric of synthetic fiber yarn and natural fiber yarn; or a blended fabric of synthetic fiber yarn and regenerated fiber yarn; or a blended fabric of synthetic fiber yarn and synthetic fiber yarn; or a blended fabric of natural fiber yarn and natural fiber yarn.

3. The separation and recovery method according to claim 2, characterized in that: The natural fiber yarn includes at least one of cotton yarn, silk yarn, wool yarn and linen yarn; And / or, the synthetic fiber yarn includes at least one of polyester yarn, nylon yarn, acrylic yarn, vinylon yarn, chloroprene yarn and spandex yarn; And / or, the regenerated fiber yarn includes at least one of viscose fiber yarn and modal yarn.

4. The separation and recovery method according to claim 1, characterized in that: The metal ions in the metal ion solution include K + 、Na + , Ca 2+ Mg 2+ At least one of .

5. The separation and recovery method according to claim 4, characterized in that: The K + The source includes at least one of KCl, KBr, K2SO4, and KNO3; and / or, the Na + The source includes at least one of NaCl, Na2SO4, and NaNO3; and / or, the Ca 2+ The source includes at least one of CaCl2 and Ca(NO3)2; And / or, the Mg 2+ The source includes at least one of MgCl2 and MgSO4.

6. The separation and recovery method according to claim 1, characterized in that: In the metal ion solution, the concentration of metal ions is 0.5 mol / L to 15.5 mol / L; And / or, the mass volume ratio of the blended fabric to the metal ion solution is not less than 1 g:50 mL.

7. The separation and recovery method according to claim 1, characterized in that: In step (4), the length of the yarn is 1 mm to 50 mm.

8. The separation and recovery method according to claim 1, characterized in that: The ultrasonic power of the ultrasonic treatment is 20kHz~60kHz; And / or, the ultrasonic treatment time is 1 s to 30 s.

9. The separation and recovery method according to claim 1, characterized in that: In step (5), the electric field is a direct current electric field; And / or, in step (5), the distance between the two electrodes of the electric field is 1 cm to 10 cm; And / or, in step (5), the voltage of the electric field is 10 kV to 100 kV; And / or, in step (5), the electric field is turned on for a period of 2 s to 30 s.

10. Use of the separation and recovery method according to any one of claims 1 to 9 in the recovery of blended fabrics.

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