Preparation method of wool regenerated yarn

Abstract

The invention discloses a method for preparing wool regenerated yarns, which comprises the following steps of: opening a pretreated waste wool textile to obtain regenerated wool fibers, mixing the regenerated wool fibers with functional fibers, blowing and carding, drawing, preparing into rough yarns, and performing ring spinning, low-torque spinning or compact spinning. The regenerated wool fibers with the content exceeding 30% are used, the application of the ring spinning technology and the low-torque spinning technology in regenerated fiber spinning is achieved, and the produced wool regenerated yarn is low in linear density, high in count, excellent in strength and elongation performance, small in hairiness amount, good in evenness and high in additional value. According to the method, the sustainable utilization value of the waste wool textiles is improved, beneficial reference is provided for high-added-value reutilization of the waste wool textiles, and meanwhile the requirement of the market for high-performance textiles is met.

Description

Technical Field

[0001] The present invention belongs to the technical field of spinning, and more specifically, the present invention relates to a method for preparing a regenerated wool yarn. Background Art

[0002] During the recycling and processing of waste wool textiles, the regenerated wool fibers are inevitably damaged, resulting in shortened fiber length and poor spinnability. To solve this problem, the regenerated wool fibers are usually mixed with functional fibers and then blended into regenerated yarns. However, at present, the rotor spinning technology is mostly used, and the produced regenerated wool yarns are mainly medium and low count yarns (the count is generally below 20 Nm, and the yarn fineness is greater than 50 tex), with low added value. Moreover, the content of regenerated wool fibers during blending is low, mostly not exceeding 30%, reducing the value of sustainable utilization. Summary of the Invention

[0003] Based on this, the object of the present invention is to provide a method for preparing medium and high count regenerated wool yarns, and this method can use a relatively high content of regenerated wool fibers.

[0004] The specific technical solutions for achieving the above invention object are as follows.

[0005] A method for preparing a regenerated wool yarn, comprising the following steps:

[0006] (1) Opening the pretreated waste wool textiles to obtain regenerated wool fibers;

[0007] (2) Mixing and carding the regenerated wool fibers and functional fibers obtained in step (1) to obtain spinning raw materials; the weight percentage of the regenerated wool fibers in the spinning raw materials is 30% - 90%;

[0008] (3) After carding the spinning raw materials obtained in step (2), outputting the spinning fiber strips in a fixed-length mode;

[0009] (4) Drawing the spinning fiber strips to a linear density of 2500 tex - 2800 tex;

[0010] (5) Making the spinning fiber strips after drawing in step (4) into roving with a linear density of 200 tex - 300 tex and a strip weight of 2.0 g·10 m -1 ~3.0 g·10 m -1 and then performing ring spinning, low-torque spinning or compact spinning to obtain regenerated wool yarns;

[0011] Among them, the process parameters of the ring spinning include: spindle speed 8000 r·min -1 ~15000 r·min -1 、yarn twist 800 turns·m-1 ~1000 turns·m -1 ; The process parameters of the low-torque spinning include: spindle speed of 8000 r·min -1 ~15000 r·min -1 、yarn twist of 700 turns·m -1 ~900 turns·m -1 、false twist speed ratio of 1.8 - 2.2.

[0012] The preparation method of the wool regenerated yarn of the present invention is to obtain regenerated wool fibers by opening up the waste wool textiles that have been pretreated (including component sorting, color sorting, disinfection, pretreatment, and opening pretreatment), and then mixing, carding, drawing, roving making, ring spinning, low-torque spinning or compact spinning with functional fibers. By adjusting the process parameters of key steps such as carding, drawing, roving making, and spinning, under the combined action of all steps, the present invention can spin yarn using more than 30% of regenerated wool fibers (up to 90% when the performance of regenerated wool fibers is good). Moreover, the produced wool regenerated yarn has a low linear density (15 tex - 50 tex), a relatively high count, excellent strength and elongation performance, less hairiness, good evenness of yarn evenness, and high added value. The present invention greatly improves the sustainable utilization value of waste wool textiles, provides a useful reference for the high-value reuse of waste wool textiles, and also helps to meet the market demand for high-performance textiles.

[0013] In addition, the preparation method of the wool regenerated yarn of the present invention does not involve water treatment processes, saves energy and reduces consumption, and does not use chemicals harmful to the environment, which is a green processing technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is the process flow chart for preparing wool regenerated yarn in Example 1 of the present invention.

[0015] Figure 2 It is the strength and elongation performance of different wool regenerated yarns in Example 2 of the present invention; among them, a is ring spinning, b is rotor spinning, and c is low-torque spinning.

[0016] Figure 3 It is the hairiness amount of more than 3 mm in different wool regenerated yarns in Example 2 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] For the convenience of understanding the present invention, the present invention will be described more comprehensively below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosed content of the present invention more thorough and comprehensive.

[0018] Unless otherwise defined, all technical and scientific terms used in this invention have the same meanings as commonly understood by those skilled in the technical field to which this invention belongs. The terms used in the description of this invention are only for the purpose of describing specific embodiments and are not intended to limit this invention. The term "and / or" used in this invention includes any and all combinations of one or more of the related listed items.

[0019] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods. The materials, reagents, etc. used, unless otherwise specified, can all be obtained from commercial sources.

[0020] In this invention, the term "waste wool textiles" refers to waste clothing and their textiles containing different contents of wool and cashmere, different blended components, and different colors. The "disinfection" can be carried out by ultraviolet disinfection or ozone disinfection; the "disassembly" refers to removing zippers, accessories, cuffs, selvages, etc. on the waste wool textiles and leaving the main body for recycling and processing; the "dust removal" refers to the operation of removing dust and impurities from the disassembled waste wool textiles using a suction dust removal device; the "component sorting" refers to classifying the waste wool textiles according to the wool content by conventional methods in this field; the "color sorting" refers to classifying by color using a color recognition intelligent device.

[0021] In some embodiments of this invention, a method for preparing a regenerated wool yarn is disclosed, including the following steps:

[0022] (1) Opening the pretreated waste wool textiles to obtain regenerated wool fibers;

[0023] (2) Mixing and carding the regenerated wool fibers obtained in step (1) with functional fibers to obtain spinning raw materials; the weight percentage of the regenerated wool fibers in the spinning raw materials is 30% - 90%;

[0024] (3) After carding the spinning raw materials obtained in step (2), outputting spinning fiber strips in a fixed-length mode;

[0025] (4) Drawing the spinning fiber strips to a linear density of 2500 tex - 2800 tex;

[0026] (5) Making the spinning fiber strips after drawing in step (4) into roving with a linear density of 200 tex - 300 tex and a strip weight of 2.0 g·10 m -1 ~3.0 g·10 m -1 and then carrying out ring spinning, low-torque spinning or compact spinning to obtain regenerated wool yarns;

[0027] Among them, the process parameters of the ring spinning include: spindle speed 8000 r·min-1 ~15,000 r·min -1 、and the twist of the spun yarn is 800 turns·m -1 ~1,000 turns·m -1 ; The process parameters of the low-torque spinning include: the spindle speed is 8,000 r·min -1 ~15,000 r·min -1 、and the twist of the spun yarn is 700 turns·m -1 ~900 turns·m -1 、and the false twist speed ratio is 1.8~2.2.

[0028] In some embodiments, the process parameters of the ring spinning further include: the draft multiple is 9~15 times, and the yarn delivery speed is 10 m·min -1 ~20 m·min -1 ; The process parameters of the low-torque spinning further include: the draft multiple is 9~15 times, and the yarn delivery speed is 10 m·min -1 ~20 m·min -1 .

[0029] In some embodiments, step (5) is carried out by low-torque spinning to obtain the regenerated wool yarn; the process parameters of the low-torque spinning include: the spindle speed is 8,000 r·min -1 ~10,000 r·min -1 、and the twist of the spun yarn is 700 turns·m -1 ~800 turns·m -1 、the false twist speed ratio is 1.9~2.1, the draft multiple is 9~15 times, and the yarn delivery speed is 10 m·min -1 ~20 m·min -1 .

[0030] In some embodiments, the process parameters of the low-torque spinning include: the spindle speed is 8,900 r·min -1 ~9,100 r·min -1 、and the twist of the spun yarn is 720 turns·m -1 ~730 turns·m -1 、the false twist speed ratio is 1.9~2.1, the draft multiple is 14~15 times, and the yarn delivery speed is 13 m·min -1 ~14 m·min -1 .

[0031] In some embodiments, the weight percentage of the regenerated wool fiber in the spinning raw material is 40%~60%.

[0032] In some embodiments, the weight percentage of the regenerated wool fiber in the spinning raw material is 45%~55%.

[0033] In some of these embodiments, the weight percentage of the recycled wool fibers in the spinning raw material is 48% to 52%.

[0034] In some of these embodiments, the functional fibers are antibacterial fibers, antistatic fibers, antibacterial and odor-proof fibers, or flame-retardant fibers.

[0035] In some of these embodiments, the functional fibers are antibacterial fibers.

[0036] In some of these embodiments, in step (3), the carding is carried out in a carding and drawing unit, which includes a roller carding machine and a flat carding machine. The process parameters of the roller carding machine are: cylinder speed: 600 r / min to 700 r / min; cylinder diameter: 380 mm to 1020 mm; draft multiple: 25 times to 35 times. The process parameters of the flat carding machine are: cylinder speed: 450 r / min to 550 r / min; cylinder diameter: 600 mm to 1400 mm; draft multiple: 30 times to 40 times.

[0037] In some of these embodiments, in step (3), the length of the fixed-length mode is 40 m to 60 m, and the back zone draft multiple is 1.3 times to 1.5 times.

[0038] In some of these embodiments, in step (4), the drawing-in includes: performing the first drawing-in on 3 to 6 spinning fiber strips obtained in step (3), and after outputting 3 to 6 spinning fiber strips in the fixed-length mode, performing the second drawing-in; repeating this step until the linear density of the spinning fiber strips after drawing-in is 2500 tex to 2800 tex.

[0039] In some of these embodiments, the length of the fixed-length mode is 40 m to 60 m, and the back zone draft multiple is 1.3 times to 1.5 times.

[0040] In some of these embodiments, during the second drawing-in, the draft multiple is 3 times to 5 times, and the draft multiple of the back zone is 1.1 times to 1.3 times.

[0041] In some of these embodiments, the process parameters of the opening in step (1) include: opening roller speed: 837 ± 5 r / min; opening roller diameter: 356 ± 5 mm.

[0042] In some of these embodiments, before preprocessing the waste wool textiles in step (1), steps of disinfecting, disassembling, dust-removing, component sorting, and color sorting the waste wool textiles are further included.

[0043] In some of these embodiments, the pretreatment of the waste wool textiles in step (1) includes the following steps: after uniformly spraying an oil agent accounting for 10% - 25% of the mass of the waste wool textiles on the surface of the waste wool textiles, sealing for 20 - 30 hours at a temperature of 0°C - 20°C and a moisture regain of 30% - 90%; the oil agent is deionized water, wool lubricant, and antistatic agent with a mass ratio of 11 - 13:0.8 - 1.2:0.2 - 0.4. The specific operation method refers to CN 116556042B for implementation.

[0044] In some of these embodiments, the functional fibers in step (1) are pretreated functional fibers, and the pretreatment includes the following steps: after uniformly spraying an antistatic agent accounting for 10% - 25% of the mass of the functional fibers on the surface of the functional fibers, sealing for 20 - 30 hours at a temperature of 0°C - 20°C and a moisture regain of 30% - 90%.

[0045] In the following embodiments of the present invention, the antibacterial fiber used is a polyhydroxyalkanoate (PHA) blend fiber (trade name: Hosu TM fiber, with an average length of 38 mm and an average fineness of 10.6 μm), which is mainly prepared by mixing two materials, polyhydroxybutyrate - valerate (PHBV) and polylactic acid (PLA), in a certain proportion, and is purchased from Nanjing Hosu Times Co., Ltd. The waste wool textiles are provided by Shenzhen Jinrongda Knitting & Apparel Co., Ltd., and are pre - consumer waste wool knitted fabrics. The yarn in this knitted fabric is 100% wool yarn, with a yarn fineness of 21 tex; the length of the wool fiber is 58 mm, the length CV value is 25.3%, the fiber fineness is 19.5 μm, and the fineness CV value is 8.0%. After pretreatment and opening, the length of the regenerated wool fiber is 28.3 mm, the length CV value is 27.5%, the fineness is 18.75 μm, and the fineness CV value is 11.6%.

[0046] The following will detail the present invention in conjunction with the attached drawings and specific embodiments.

[0047] Example 1 Preparation method of wool regenerated yarn

[0048] In this example, 40% regenerated wool fiber + 60% antibacterial fiber, 50% wool regenerated fiber + 50% antibacterial fiber, and 60% regenerated wool fiber + 40% antibacterial fiber are used as spinning raw materials respectively, and nine kinds of wool regenerated yarns are spun by three different spinning methods: ring spinning, rotor spinning, and low - torque spinning, including the following steps (please refer to Figure 1 ):

[0049] 1. Pretreatment

[0050] After disinfecting, disassembling, dusting, sorting by composition, and sorting by color the waste wool textiles, perform carding pretreatment, i.e., evenly spray an oil agent accounting for 20% of the mass of the waste wool textiles (deionized water: wool lubricant: antistatic agent = 12:1:0.3) on the surface of the waste wool textiles, and then seal them for 24 hours under the conditions of 0°C and 90% moisture regain;

[0051] Evenly spray an antistatic agent accounting for 20% of the mass of the antibacterial fibers on the surface of the antibacterial fibers, and seal them for 24 hours under the conditions of 0°C and 90% moisture regain;

[0052] 2. Carding

[0053] Feed the pretreated waste wool textiles (cut into pieces) into a carding machine (carding roller speed: 837 r / min; carding roller diameter: 356 mm) according to the weight percentage ratio for carding to obtain regenerated wool fibers;

[0054] 3. Mixing

[0055] Mix and card the regenerated wool fibers and antibacterial fibers to obtain spinning raw materials;

[0056] 4. Carding and Combing

[0057] Feed the spinning raw materials in step 3 into a carding and combing machine (including 1 roller carding machine (coarse card clothing), a blower, a feed hopper, and 1 flat carding machine (fine card clothing)), and output them in a fixed-length mode (50 m, draw-off speed 15 m / min) to obtain evenly distributed spinning fiber strips;

[0058] Among them, the process parameters of the roller carding machine are: cylinder speed: 680 r / min; cylinder diameter: 380 mm; draft multiple: 30 times; the process parameters of the flat carding machine are: cylinder speed: 500 r / min; cylinder diameter: 600 mm; draft multiple: 33 times;

[0059] 5. Drawing

[0060] Perform the first drawing (draft 4 times, back zone draft 1.4 times) on 4 spinning fiber strips, and output 4 strips in a fixed-length mode (50 m, draw-off speed 15 m / min) and then perform the second drawing (draft 4 times, back zone draft 1.2 times); the linear densities of the drawn spinning fiber strips are 2700 tex (40% regenerated wool fibers + 60% antibacterial fibers), 2325 tex (50% regenerated wool fibers + 50% antibacterial fibers), and 2800 tex (60% regenerated wool fibers + 40% antibacterial fibers) respectively.

[0061] 6. Rotor Spinning

[0062] Feed the carded spinning fiber sliver after step 5 into a rotor spinning machine (type TS-3) for yarn spinning (process parameters are shown in Table 1) to obtain recycled wool yarn. During this process, there will be end-breaking phenomena, which should be related to the too short fibers.

[0063] Table 1 Rotor spinning process parameters

[0064]

[0065] 7. Ring spinning and low-twist spinning

[0066] Feed the carded spinning fiber sliver after step 5 into a roving frame (type FA497, process parameters are shown in Table 2, adjusted according to the characteristics of the raw materials and the test results of spinnability) to obtain rovings (roving specifications are shown in Table 3). During this process, there will be end-breaking phenomena, which should be related to the too short fibers.

[0067] Table 2 Roving frame process parameters

[0068]

[0069]

[0070] Table 3 Roving specifications

[0071]

[0072] Then install the rovings on a ring spinning machine (type ZJ1298, process parameters are shown in Table 4) for yarn spinning (the ambient temperature for spinning is 17°C - 23°C, and the humidity is above 75%RH) to obtain recycled wool yarn.

[0073] Table 4 Ring spinning and low-twist spinning process parameters

[0074]

[0075] Example 2 Performance determination of 9 kinds of recycled wool yarns in Example 1

[0076] 1. Yarn linear density

[0077] For the test of yarn count, i.e., yarn linear density, refer to the standard GB / T 4743-2009 "Determination of linear density of hank yarns of textile wound yarns". Select a YG086D type lea strength tester and a balance with a precision of one-thousandth of the mass. Under the specified standard atmospheric conditions, use the lea strength tester to take 100m of yarn, weigh the yarn on the balance, and then calculate the linear density of the yarn. Take the average value of 3 tests for each sample.

[0078] The test results of yarn linear density (spinning yarn linear density is 25 tex) are shown in Table 5.

[0079] Table 5 Linear density of nine kinds of recycled wool yarns

[0080]

[0081] After spinning, the actual linear density of nine kinds of wool regenerated yarns was measured, and it was found that the linear density of low-torque spun yarn was significantly lower than that of rotor-spun and ring-spun yarns.

[0082] 2. Yarn strength and elongation performance

[0083] The strength and elongation performance of the yarns were tested on a universal tensile testing machine with reference to the standard GB / T 3916-2013 "Textiles - Yarns in packages - Determination of breaking force and elongation at break of single yarns (CRE method)". The pre-tension was 0.5 cN / tex, the test speed was 500 mm / min, and the clamping distance was 500 mm. The average value of 30 tests was taken for each specimen.

[0084] The breaking strength and elongation at break of the nine kinds of wool regenerated yarns prepared (with a set spinning linear density of 25 tex) are as Figure 2 shown.

[0085] Generally speaking, the breaking strength of low-torque spun and ring-spun yarns is significantly better than that of rotor-spun yarns, and the breaking strength of low-torque spun yarn is the best. This is probably because low-torque spinning increases the transfer frequency of fibers in the yarn cross-section, improves the cohesion between fibers, and thus increases the strength of the regenerated wool fiber yarn. Compared with ring-spun and low-torque spun yarns, the fluctuations in the breaking strength and elongation at break of rotor-spun regenerated yarns are significantly larger. The breaking strength of rotor-spun yarn is low, and the strength and elongation performance vary greatly with different fiber blending ratios, because the fiber cohesion in rotor-spun yarn is weak and there are many hooked fibers in the yarn.

[0086] For ring-spun regenerated yarns, when the proportion of regenerated wool fibers is 50%, the highest strength of the yarn is 8.61 cN / tex and the elongation at break is 19.75%. When the proportion of regenerated wool fibers reaches 60%, the breaking strength drops to 7.77 cN / tex, a decrease of about 9.7%, and the elongation at break drops to 15.60%, a decrease of about 21.0%. For rotor-spun regenerated yarns, when the content of regenerated wool fibers is 50%, the breaking strength and elongation at break are the highest, which are 6.64 cN / tex and 18.19% respectively. However, when the content of regenerated wool fibers is 40% and 60%, the breaking strength and elongation at break of the yarn are both reduced by nearly 30% compared with when the content of regenerated wool fibers is 50%. For low-torque spun regenerated yarns, when the content of regenerated wool fibers is 40% and 50%, the strength and elongation performance of the yarns are basically the same, the breaking strength is about 9.37 cN / tex, and the elongation at break is about 14.79%.

[0087] Therefore, low-twist spinning and ring spinning, especially low-twist spinning, are more conducive to spinning high-performance recycled yarns than rotor spinning.

[0088] 3. Yarn hairiness

[0089] Excessive hairiness not only affects the smooth progress of production but also damages the appearance and usability of the yarn. Generally, hairiness with a length of 3 mm or more can be regarded as harmful hairiness, which will affect the weaving effect.

[0090] The hairiness of the yarn is tested according to the standard FZ / T 01086-2020 "Textiles - Determination of yarn hairiness - Projection counting method". Using a YG173 A-type yarn hairiness tester, the hairiness of the wool recycled yarn is measured under the conditions of 20 °C and a relative humidity of 65%. The pre-tension is 0.25 cN / tex, the length of the yarn segment for hairiness testing is 10 m, the testing speed is 30 m / min, and the average value of 10 tests is taken for each sample.

[0091] The test results of the yarn hairiness of 9 kinds of wool recycled yarns are shown in Table 6 and Figure 3 .

[0092] Table 6 Hairiness properties of nine kinds of wool recycled yarns

[0093]

[0094]

[0095] From Table 6 and Figure 3 the results, it can be seen that the amount of hairiness above 3 mm in the wool recycled yarns prepared by low-twist spinning is the lowest among the three spinning methods, significantly better than ring spinning and rotor spinning, while the amount of hairiness of rotor spinning is the largest. Therefore, low-twist spinning and ring spinning, especially low-twist spinning, are more conducive to spinning medium and high count recycled yarns with less hairiness than rotor spinning.

[0096] 4. Yarn evenness

[0097] The evenness of the yarn is tested according to the standard GB / T 3292.1-2008 "Textiles - Test method for yarn evenness - Part 1: Capacitance method". Using a YG139 BA-type yarn evenness tester, the main test indicators include CV, details, thick places, neps, etc. The test speed is 100 m / min, a total of 400 m of yarn is tested in 4 units, and the average value of 3 tests is taken for each sample.

[0098] The evenness of nine kinds of wool recycled yarns is shown in Table 7.

[0099] Table 7 Evenness of nine kinds of wool recycled yarns

[0100]

[0101]

[0102] Overall, the evenness of ring-spun recycled yarn is the best, followed by that of low-twist-spun recycled yarn, and the worst is that of rotor-spun recycled yarn. When the content of recycled wool fiber is 40%, the slubs +50% and neps +200% contained in the recycled yarns spun by the three spinning methods are almost higher than those of the recycled yarns spun when the content of recycled wool fiber is 50% and 60%. This may be because the length of the antibacterial fiber with a high content ratio (38 mm) is greater than that of the recycled wool fiber (28 mm), resulting in the formation of more slubs and neps. From the perspective of the coefficient of variation CV index of yarn evenness, there is little difference in the three blended-ratio recycled wool blended yarns prepared by ring spinning; the CV difference of the recycled yarns prepared by rotor spinning is relatively obvious. The CV value of the recycled yarn is the highest when the content of recycled wool fiber is 40%, followed by 60%, and the lowest is 18.21% when the content is 50%; there are also certain differences in the CV values of the evenness of the recycled yarns prepared by low-twist spinning. However, the CV value of the evenness of the recycled yarn with the relatively highest content of recycled wool fiber of 60% is the lowest. It can be seen that low-twist spinning has certain advantages in spinning shorter recycled fiber yarns.

[0103] Since the recycled wool fibers are inevitably damaged during the recycling process, resulting in shortened fiber length and decreased spinnability, the present invention adjusts the process parameters of key steps such as opening and mixing, carding, drawing, roving, and spinning, controls the content of recycled wool fibers between 30% and 90%, and uses ring spinning technology and low-twist spinning technology to achieve the spinning of high-count wool recycled yarns, and improves the performance of the wool recycled yarns. The prepared wool recycled yarns have high strength and elongation performance, less hairiness, and better evenness, and the yarn performance is excellent. Among them, when the content of recycled wool fiber is 50% and low-twist spinning is carried out, the comprehensive performance of the obtained wool recycled yarn is the best. The present invention provides a useful reference for the high-value reuse of waste wool textiles, and also helps to meet the market demand for high-performance textiles.

[0104] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0105] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A method for preparing regenerated wool yarn, characterized in that: The following steps are involved: (1) opening the pretreated waste wool textiles to obtain regenerated wool fibers; (2) mixing and combing the regenerated wool fiber and the functional fiber described in step (1) to obtain a spinning raw material; the weight percentage of the regenerated wool fiber in the spinning raw material is 30% to 90%; (3) combing the spinning raw material described in step (2) and outputting the spinning fiber strips through a fixed length mode; (4) drawing the spun fiber strips to a linear density of 2500 tex to 2800 tex; (5) The spun fiber strips after drawing in step (4) are made into a strip with a linear density of 200 tex to 300 tex and a strip weight of 2.0 g / 10 m -1 ~3.0g·10m -1 After the roving is produced, it is ring-spun, low-torque spun or compact-spun to obtain regenerated wool yarn; The process parameters of the ring spinning process include: spindle speed 8000r·min -1 ~15000r·min -1 , spun yarn twist 800 twist·m -1 ~1000 twists·m -1 The process parameters of low torque spinning include: spindle speed 8000r·min -1 ~15000r·min -1 , spun yarn twist 700 twist·m -1 ~900 twists·m -1 , false twist speed ratio is 1.8~2.

2.

2. The method for preparing regenerated wool yarn according to claim 1, characterized in that: The process parameters of the ring spinning also include: drafting multiple 9 to 15 times, yarn output speed 10 m / min -1 ~20m·min -1 The process parameters of low torque spinning also include: drafting multiple 9 to 15 times, yarn output speed 10m / min -1 ~20m·min -1 .

3. The method for preparing regenerated wool yarn according to claim 2, characterized in that: Step (5) adopts low torque spinning to obtain regenerated wool yarn; The process parameters of the low torque spinning include: spindle speed 8000r·min -1 ~10000r·min -1 , spun yarn twist 700 twist·m -1 ~800 twists·m -1 , false twist speed ratio 1.9~2.1, drafting multiple 9~15 times, yarn output speed 10m·min -1 ~20m·min -1 .

4. The method for preparing regenerated wool yarn according to claim 3, characterized in that: The process parameters of the low torque spinning include: spindle speed 8900r·min -1 ~9100r·min -1 , spun yarn twist 720 twists·m -1 ~730 twist·m -1 , false twist speed ratio 1.9~2.1, drafting multiple 14~15 times, yarn output speed 13m·min -1 ~14m·min -1 .

5. The method for preparing regenerated wool yarn according to claim 1, characterized in that: The weight percentage of the regenerated wool fiber in the spinning raw material is 40% to 60%, preferably 45% to 55%; And / or, the functional fiber is antibacterial fiber, antistatic fiber, antibacterial and deodorizing fiber or flame retardant fiber, preferably antibacterial fiber.

6. The method for preparing regenerated wool yarn according to claim 1, characterized in that: The cleaning and combing in step (3) is carried out in a cleaning and combing combined machine, which includes a roller combing machine and a flat carding machine. The process parameters of the roller carding machine are: cylinder speed: 600r / min~700r / min; cylinder diameter: 380mm~1020mm; drafting multiple: 25 times~35 times; the process parameters of the flat carding machine are: cylinder speed: 450r / min~550r / min; cylinder diameter: 600mm~1400mm; drafting multiple: 30 times~40 times; And / or, the length of the fixed-length mode in step (3) is 40m to 60m, and the drafting multiple in the rear zone is 1.3 to 1.5 times.

7. The method for preparing regenerated wool yarn according to claim 1, characterized in that: The combining in step (4) comprises: drawing 3 to 6 spun fiber strips in step (3) for the first time, outputting 3 to 6 spun fiber strips in a fixed length mode, and then drawing them for the second time; repeating this step until the linear density of the spun fiber strips after drawing is 2500 tex to 2800 tex; Preferably, the length of the fixed-length mode is 40m to 60m, and the drafting multiple in the rear zone is 1.3 to 1.5 times; Preferably, during the second drawing, the drafting multiple is 3 to 5 times, and the drafting multiple in the rear zone is 1.1 to 1.3 times.

8. The method for preparing regenerated wool yarn according to any one of claims 1 to 7, characterized in that: The process parameters for opening in step (1) include: opening roller speed: 837±5r / min; opening roller diameter: 356±5mm; And / or, before pre-treating the waste wool textiles in step (1), the step further includes disinfecting, disassembling, removing dust, sorting components, and sorting colors of the waste wool textiles.

9. The method for preparing regenerated wool yarn according to any one of claims 1 to 7, characterized in that: The pretreatment of the waste wool textiles in step (1) comprises the following steps: after uniformly spraying 10% to 25% of the mass of the waste wool textiles with an oil agent on the surface of the waste wool textiles, sealing the waste wool textiles at a temperature of 0°C to 20°C and a moisture regain of 30% to 90% for 20 to 30 hours; the oil agent is deionized water, wool oil agent, and antistatic agent in a mass ratio of 11 to 13: 0.8 to 1.2: 0.2 to 0.

4.

10. The method for preparing regenerated wool yarn according to any one of claims 1 to 7, characterized in that: The functional fiber described in step (2) is a pretreated functional fiber, and the pretreatment includes the following steps: after uniformly spraying 10% to 25% of the weight of the functional fiber on the surface of the functional fiber, the temperature is 0°C to 20°C and the regain is 30% to 90% and the sealing is carried out for 20 hours to 30 hours.

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