A non-water printing and dyeing closed-loop production and waste fabric regeneration preparation process

Abstract

The application discloses a kind of non-water printing dyeing closed loop production and waste fabric regeneration preparation process, belong to textile regeneration printing and dyeing technical field.The application adopts visual identification and hyperspectral double mode sorting waste fabric, and the pure terylene, pure cotton, terylene cotton blended yarn three kinds of differential chemical regeneration preparation regenerated fiber are separated;Waste medium and residual dye are filtered, rectification, membrane separation purification circulation reuse;Printing edge material is recycled front end regeneration, and two-way waste heat intercommunication of regeneration and printing and dyeing is opened, and production wastewater is double-membrane treated and is all reused, and crystalline salt is recycled.The application realizes terylene cotton blended fabric component accurate separation high-value regeneration, constructs raw material, medium, solid waste, water resource, heat energy full-link closed loop system, no printing and dyeing wastewater discharge, adapts single factory independent, industrial park cluster two kinds of production modes, greatly reduces energy consumption and pollutant emission, improves waste textile resource utilization and product added value.

Description

Technical Field

[0001] This invention relates to the field of textile recycling and dyeing technology, specifically to a closed-loop production process for waterless printing and dyeing and a process for the recycling of waste fabrics. Background Technology

[0002] Textile printing and dyeing is a core processing link in the textile industry. Traditional printing and dyeing processes are mainly aqueous, consuming large amounts of industrial water resources and continuously generating recalcitrant wastewater with high salinity, high color intensity, and high COD. This results in high wastewater treatment costs and significant environmental pressure, posing a dual problem of water waste and ecological pollution, making it difficult to align with the current industry trend towards low-carbon, energy-saving, and near-zero emission cleanliness. Meanwhile, China has a large and stable stock of waste textiles, making the efficient recycling and reuse of waste fabrics a critical issue that the industry urgently needs to address.

[0003] Currently, the mainstream methods for treating waste fabrics are mostly mechanical opening, crushing and downgrading for reuse, incineration, or landfill. These methods generally suffer from severe mechanical damage to fibers, low resource utilization rates, and a tendency to generate secondary pollution, failing to achieve high-value recycling of waste fabrics. Existing chemical recycling technologies are limited in function and have poor material compatibility, making it difficult to achieve component separation and graded regeneration of polyester-cotton blended fabrics. The stability of recycled fiber performance is insufficient, and these are merely fragmented, single-process technologies, unable to form a systematic, closed-loop production system.

[0004] In the field of printing and dyeing technology, while existing waterless printing and dyeing processes can eliminate the generation of printing and dyeing wastewater at the source, the process systems are relatively independent, resulting in problems such as the inability to internally dispose of solid waste, an imperfect media and dye recovery system, and high energy consumption. At present, waste fabric recycling processes and waterless printing and dyeing processes in the industry are independent and applied separately, failing to form a coupled and linked closed-loop production structure. This leads to technical shortcomings such as the disconnect between raw material recycling and end-of-life printing and dyeing, the inability to recycle solid waste resources, and the waste of media and waste heat resources. Consequently, it is impossible to achieve a green closed-loop production process, which greatly limits its industrial application and promotion. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a closed-loop production process for waterless printing and dyeing and the recycling of waste fabrics. This process aims to solve the technical problems of high water consumption in traditional textile production, serious downgrading of waste fabrics, disconnect between recycling and printing and dyeing processes, low recycling rate of polyester-cotton blended fabrics, inability to reuse waterless printing and dyeing mediums and dyes in a closed loop, waste of solid waste and waste heat resources, and inability to achieve near-zero emissions in production. This invention achieves a closed-loop green production process that integrates high-value recycling of multi-material waste fabrics, precise waterless printing and dyeing, recycling of mediums and dyes, and bidirectional coupling of solid waste and waste heat.

[0006] This invention adopts the following technical solution: a closed-loop production process for waterless printing and dyeing and the recycling of waste fabrics, comprising the following steps: S1: Waste fabric sorting and pretreatment: A dual-mode sorting system combining visual recognition and hyperspectral imaging is used to accurately classify recycled waste textiles, distinguishing between pure polyester, pure cotton, and polyester-cotton blended fabrics. After removing accessories, stains, and discolored impurities, each type of fabric is crushed and pretreated to remove impurities. S2: Differentiated chemical regeneration process for preparing recycled fibers: Specialized chemical regeneration process is used for the three types of waste fabrics after S1 classification to prepare corresponding recycled fibers, so as to achieve high-value differentiated regeneration of fabrics of different materials and avoid mixed materials and downgraded utilization. S3: Regenerated fabric weaving: The various recycled fibers prepared in S2 are woven and processed to obtain recycled fabric greige that is suitable for waterless printing and dyeing processes. S4: Precision Waterless Printing and Dyeing: The recycled fabric obtained in S3 undergoes a closed-loop waterless printing and dyeing process, eliminating the traditional sizing, washing, and soaping steps. The amount of dye applied is precisely matched and controlled according to the fabric texture and weaving structure characteristics, achieving micron-level precision printing and nearly 100% dye uptake. Simultaneously, masterbatch can be selectively added in the S2 spinning process to achieve solution dyeing, with subsequent matching of reduced printing or no printing treatment to reduce dye consumption from the source. The waterless printing and dyeing process uses supercritical carbon dioxide, organic solvents, or special non-aqueous media as dye carriers, and the entire process is carried out in a closed loop. S5: Integrated closed-loop recycling and reuse of non-aqueous media and dyes: Collect the undyed residual dye and waste non-aqueous media carrying dye in the S4 process, and send them to the media regeneration device. They are purified and refined through a coupling process of distillation, filtration and membrane separation. The purified non-aqueous media is recycled to the S4 waterless printing and dyeing process. The residual dye is purified and compounded and reused in printing production. S6: Closed-loop coupling of solid waste and waste heat throughout the entire process: All the cutting scraps and defective recycled fabrics generated in the S4 printing process are recycled back to the S1 process, constructing an internal recycling system for fabric solid waste; the waste heat exchange channel between the recycling preparation process and the waterless printing and dyeing process is opened up, and the waste heat from the high-temperature operation of waterless printing is used to heat the fabric recycling, solvent distillation, and reactor operation. The waste heat from the recycling process is used to preheat the greige fabric and non-aqueous media in reverse, realizing a two-way energy-saving closed loop; S7: Finished product inspection and packaging: Conduct performance and appearance inspections on the finished fabrics that have completed waterless printing and dyeing, and pack and store them in the warehouse after they pass the inspection.

[0007] Furthermore, the chemical recycling process for pure polyester waste fabrics in S2 includes: performing an alcoholysis reaction on the pretreated waste polyester fabric to generate an alcoholysis solution containing diethyl terephthalate; simultaneously carrying out decolorization and purification treatment on the alcoholysis solution, followed by cooling, crystallization, filtration, and drying to obtain high-purity diethyl terephthalate monomer; polymerizing the monomer to prepare recycled polyester chips, and finally obtaining high-performance recycled polyester fibers through melt spinning.

[0008] Furthermore, the alcoholysis reaction and decolorization treatment are completed continuously and in one integrated rotary reactor, using segmented temperature gradient precise control: the temperature inside the reactor is controlled not to exceed 200℃ to complete the fabric decolorization treatment, and the temperature is raised to above 200℃ for the polyester alcoholysis reaction. There is no need for intermediate material transfer, realizing continuous integrated operation of decolorization and alcoholysis, and realizing continuous integrated production of decolorization and alcoholysis processes, effectively simplifying the process flow and improving production efficiency.

[0009] Furthermore, the chemical regeneration process of pure cotton waste fabrics in S2 includes: first, decolorizing and removing impurities from the pretreated pure cotton fabrics, then mechanically shredding them and precisely compounding them according to the degree of fiber polymerization to obtain standardized regenerated pulp with a degree of polymerization of 350~550; then, using solvent dissolution to prepare a stable spinning solution from the regenerated pulp, and finally, through spinning and coagulation molding, obtaining high-toughness regenerated cellulose fibers.

[0010] Furthermore, the chemical regeneration process for polyester-cotton blended waste fabrics in S2 includes: using a specific selective solvent to separate the components of the pretreated blended fabric, selectively dissolving the polyester component while completely retaining the cotton fiber component; the separated polyester component is then decolorized, alcoholized, polymerized, and spun to regenerate recycled polyester fiber; the separated cotton component is then purified, pulped, dissolved, and spun to regenerate recycled cellulose fiber, achieving 100% high-value recycling of both fibers in the blended fabric.

[0011] Furthermore, the integrated recycling process of non-aqueous media and dyes in S5 specifically involves: collecting the mixed liquid of non-aqueous media containing dyes discharged from the closed dyeing system; firstly, removing suspended solid impurities through precision filtration; then, effectively separating the non-aqueous media and dye components through distillation; and finally, deeply purifying the non-aqueous media using membrane separation technology. The purity of the purified non-aqueous media meets the standards for anhydrous dyeing recycling and can be directly reused in production. For degraded and unusable dye waste residue, it is sent to a pyrolysis system for heat energy recovery, eliminating the discharge of solid waste.

[0012] Furthermore, the entire production process adopts a differentiated recycling model for water. Equipment cooling water and trace cleaning wastewater are all reused after being deeply treated by ultrafiltration and reverse osmosis dual membrane processes. The concentrated water generated during treatment is concentrated by electrodialysis and crystallized by triple-effect evaporation. The precipitated crystal salts can be recycled as production aids, achieving near-zero discharge of production water resources.

[0013] Furthermore, the process of this invention can be adapted to two modes: single-plant integrated closed-loop production and industrial park cluster closed-loop production. In the single-plant mode, it can realize the immediate recycling and reuse of production scraps and defective fabrics within the plant, as well as the self-circulation of non-aqueous media and production waste heat within the plant. In the industrial park mode, a centralized recycling and media recovery center can be built to uniformly process the waste fabrics and waste non-aqueous media of various production entities within the park, and coordinate the comprehensive utilization of waste heat resources to achieve low-carbon and zero-pollution production in industrial clusters.

[0014] The beneficial effects achieved by the present invention using the above technical solution are as follows: 1. By constructing a closed-loop production system that integrates the chemical regeneration of multi-material waste fabrics, closed-loop waterless precision printing, integrated recycling of media and dyes, and bidirectional coupling of solid waste and waste heat, the integrated recycling of raw materials, media, dyes, solid waste, water resources and heat energy can be realized, effectively achieving green and low-carbon production.

[0015] 2. Differentiated and exclusive chemical recycling processes are set up for three types of waste textiles: pure polyester, pure cotton, and polyester-cotton blends. This solves the limitation that traditional polyester-cotton blend fabrics can only be downgraded and reused as a whole. It achieves precise separation of polyester and cotton fibers and high-value recycling by quality separation, effectively improving the resource utilization rate and product added value of waste textiles.

[0016] 3. The single-reactor gradient temperature control integrated process is adopted to continuously complete the decolorization and alcoholysis of polyester fabrics in the same equipment. There is no need for material transfer and equipment switching, which effectively simplifies the production process, improves production efficiency and the purity of recycled monomers, and ensures stable and uniform performance of recycled fibers.

[0017] 4. Adopting a closed-loop waterless printing and dyeing process, eliminating the traditional printing and dyeing processes of sizing, washing, and soaping, thus preventing the generation of printing and dyeing wastewater from the source; combined with precise material control printing on fabrics and a spinning solution coloring reduction process, effectively reducing dye consumption and improving printing accuracy and dye utilization.

[0018] 5. By coupling filtration, distillation, and membrane separation processes, the system achieves efficient recovery and reuse of non-aqueous media and residual dyes. Combined with a production water quality recycling and crystallization salt reuse system, the system achieves near-zero discharge of production water resources, significantly reducing pollutant emissions and demonstrating excellent green and environmentally friendly characteristics.

[0019] 6. By establishing an energy-saving closed-loop system that integrates full recycling of solid waste and bidirectional heat exchange, it is compatible with both single-plant independent production and industrial park cluster production. It has a wide range of applicable scenarios, significant energy-saving effects, and good industrial value, economic benefits, and environmental benefits. Attached Figure Description

[0020] Figure 1 This is a closed-loop architecture diagram of the entire process of the present invention; Figure 2 This is a flowchart of the multi-material waste fabric recycling process of the present invention; Figure 3 This is a flowchart illustrating the integrated recycling and reuse process of non-aqueous media and dyes according to the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1: Closed-loop production process for pure polyester waste fabric, such as... Figures 1-3 As shown: S1. Waste Fabric Sorting and Pre-treatment: Using a dual-mode sorting device combining visual recognition and hyperspectral imaging, pure polyester waste fabrics are accurately screened, and printing accessories, stains, and discolored impurities are completely removed. The screened polyester fabrics are then crushed and finely pre-treated to obtain clean polyester waste raw materials.

[0023] S2. Chemical Regeneration of Polyester Fabric: The pretreated polyester fabric is put into a rotary reactor and the integrated treatment is completed by gradient temperature control. First, the reactor temperature is controlled at ≤200℃ to complete the decolorization and purification of the fabric and reaction solution. Then, the temperature is raised to >200℃ to carry out alcoholysis reaction to obtain alcoholysis solution containing diethyl terephthalate. The alcoholysis solution is cooled, crystallized, filtered and dried to obtain high-purity monomers. The monomers are polymerized to generate recycled polyester chips, and high-performance recycled polyester fibers are prepared by melt spinning process.

[0024] S3. Recycled fabric weaving: The prepared recycled polyester fibers are warped, weft-knitted, and woven. The weaving density is adjusted to match the waterless printing process parameters to obtain a recycled polyester fabric with a uniform structure that is suitable for waterless printing and dyeing.

[0025] S4. Precision Waterless Printing and Dyeing: Using closed-loop printing and dyeing equipment, supercritical carbon dioxide, organic solvents, or special non-aqueous media are selected as dye carriers to carry out waterless printing and dyeing processing on recycled polyester fabrics, eliminating the sizing, washing, and soaping processes throughout the entire process; the amount of dye applied is precisely controlled according to the fabric texture and weaving warp and weft structure to achieve micron-level precision printing and ensure a near 100% dye uptake rate; masterbatch can be added during the spinning stage to complete the solution coloring, and the downstream adopts reduced-volume printing or no-printing processes to reduce dye input from the source.

[0026] S5. Closed-loop recycling of medium dyes: Collect untreated residual dyes and waste non-aqueous media during the printing and dyeing process, and purify them through multi-stage coupling of precision filtration, distillation, and membrane separation. The purified non-aqueous media are reconnected to the waterless printing equipment for recycling, and the purified dyes are compounded and used for subsequent printing production.

[0027] S6. Solid waste heat coupling cycle: All printing and cutting scraps and defective fabrics are recycled back to the S1 pretreatment process to achieve closed-loop regeneration of fabric solid waste; the waste heat from the high-temperature anhydrous dyeing process is used to heat the alcoholysis and solvent distillation processes in the reactor, while the waste heat from the regeneration process is used to preheat the fabric and non-aqueous medium in reverse to achieve bidirectional energy saving.

[0028] S7. Finished Product Inspection and Packaging: The finished fabrics after printing and dyeing are tested for color fastness, breaking strength, and appearance flatness. After all indicators meet the standards, they are finished, shaped, packaged, and put into storage.

[0029] Table 1. Comparison of Closed-Loop Process and Traditional Water Dyeing Process for Pure Polyester: Example 2: Closed-loop production process of pure cotton waste fabric, such as... Figure 1-3 As shown: S1. Waste fabric sorting and pretreatment: Pure cotton waste fabrics are screened by a dual-mode sorting system that combines visual recognition with hyperspectral imaging to remove stains, accessories and various impurities. After crushing and impurity removal, clean pure cotton waste raw materials are obtained.

[0030] S2. Chemical Regeneration of Pure Cotton Fabric: The pretreated pure cotton fabric is decolorized, impurities removed, and mechanically shredded. The fiber polymerization degree is precisely controlled to obtain standardized recycled pulp with a polymerization degree of 350~550. The recycled pulp is prepared into a uniform and stable spinning solution using a general solvent dissolution process. After spinning, coagulation and shaping, and stretching and setting, high-toughness regenerated cellulose fiber is prepared.

[0031] S3. Regenerated fabric weaving: Regenerated cellulose fibers are woven into uniform and dense recycled cotton fabric, which is suitable for closed-loop waterless dyeing operations.

[0032] S4. Precision Waterless Printing and Dyeing: Supercritical carbon dioxide, organic solvents, or special non-aqueous media are used as dye carriers to carry out closed-loop waterless printing and dyeing on recycled cotton fabrics, eliminating the traditional washing, soaping, and sizing processes; the amount of dye applied is precisely controlled in combination with the fabric texture structure to achieve high-precision printing operations. It can be combined with solution dyeing processes to achieve reduced printing or no printing production, reducing dye consumption from the source.

[0033] S5. Closed-loop recycling of media and dyes: The waste non-aqueous media and residual dyes generated in the production process are purified by filtration, distillation and membrane separation. The purified media and dyes are recycled and reused in the waterless printing process.

[0034] S6. Solid waste heat coupling circulation: All scraps and defective fabrics generated during the production process are recycled back to the pretreatment process. Relying on the waste heat interconnection network of the whole plant, the recycling process and the dyeing process complement each other in two directions to save energy.

[0035] S7. Finished Product Inspection and Packaging: Complete the inspection of fabric performance and appearance, and sort, package and put qualified products into storage.

[0036] Table 2. Comparison of performance between recycled pure cotton fabrics and traditional recycling processes: Example 3: Closed-loop production process for the recycling of polyester-cotton blended waste fabrics, such as... Figure 1-3 As shown: S1. Sorting and pretreatment of waste fabrics: The waste polyester-cotton blended fabrics are sorted, and after removing impurities and stains, they are crushed and pretreated to obtain clean blended fabric raw materials.

[0037] S2. Blended Fabric Separation and Regeneration: A special selective solvent is used to separate the components of the blended fabric, selectively dissolving the polyester component while fully preserving the cotton fiber component; the separated polyester component is decolorized, subjected to gradient temperature controlled alcoholysis, polymerization, and spinning to prepare recycled polyester fiber; the separated cotton component is purified, pulped, dissolved, and spun to prepare recycled cellulose fiber, achieving high-value separation and regeneration of the two types of fibers.

[0038] S3. Recycled fabric weaving: The two types of recycled fibers are woven separately to obtain the corresponding recycled polyester fabric and recycled cotton fabric.

[0039] S4. Precision Waterless Printing and Dyeing: Depending on the fabric material, supercritical carbon dioxide, organic solvents or special non-aqueous media are matched as dye carriers to implement closed-loop waterless precision printing and dyeing. The traditional washing, soaping and sizing processes are eliminated throughout the process. It can be combined with solution dyeing process to achieve reduced printing or no printing production, reducing dye consumption from the source.

[0040] S5-S7, Recycling and Finishing Processes: The non-aqueous media and dye closed-loop recycling, solid waste waste heat coupling recycling, and finished product inspection and packaging processes in this embodiment are all consistent with the above embodiments. Through closed-loop management of the entire process, the green circular production of polyester-cotton blended fabrics is completed.

[0041] Table 3. Comparison of Polyester-Cotton Blended Fabrics Using Differentiated Recycling and Traditional Processes: In summary, the above three embodiments correspond to the closed-loop production processes of three mainstream waste textile products: pure polyester, pure cotton, and polyester-cotton blends, respectively, which fully verify the feasibility, stability, and universality of the process scheme of the present invention.

[0042] Compared to traditional mechanical recycling and aqueous dyeing production models, this invention employs differentiated chemical regeneration technology, addressing the industry pain point that traditional blended fabrics can only be downgraded and reused, thus achieving high-value recycling of multi-material waste fabrics. Through a closed-loop waterless printing and dyeing process, it completely eliminates dyeing wastewater pollution at the source. Relying on a fully closed-loop system of integrated media and dye recovery and bidirectional coupling of solid waste and waste heat, it effectively solves the drawbacks of traditional processes, such as low resource utilization, high energy consumption, significant environmental pollution, and low product added value. This invention's process is adaptable to the production of multi-material fabrics, exhibits strong stability, and is applicable to a wide range of scenarios. It can meet the needs of independent single-plant production and industrial park cluster-based green production, possessing significant economic, environmental, and industrialization promotion value.

[0043] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0044] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A closed-loop production process for waterless printing and dyeing, and a recycling process for waste fabrics, characterized in that, Includes the following steps: S1: Waste fabric sorting and pretreatment: A dual-mode sorting system combining visual recognition and hyperspectral imaging is used to accurately classify recycled waste textiles, distinguishing between pure polyester, pure cotton, and polyester-cotton blended fabrics. After removing accessories, stains, and discolored impurities, each type of fabric is crushed and pretreated to remove impurities. S2: Differentiated chemical regeneration process for preparing recycled fibers: Specialized chemical regeneration process is used for the three types of waste fabrics after S1 classification to prepare corresponding recycled fibers, so as to achieve high-value differentiated regeneration of fabrics of different materials and avoid mixed materials and downgraded utilization. S3: Regenerated fabric weaving: The various recycled fibers prepared in S2 are woven and processed to obtain recycled fabric greige that is suitable for waterless printing and dyeing processes. S4: Precision Waterless Printing and Dyeing: The recycled fabric obtained in S3 undergoes a closed-loop waterless printing and dyeing process, eliminating the traditional sizing, washing, and soaping steps. The amount of dye applied is precisely matched and controlled according to the fabric texture and weaving structure characteristics, achieving micron-level precision printing and nearly 100% dye uptake. Simultaneously, masterbatch can be selectively added in the S2 spinning process to achieve solution dyeing, with subsequent matching of reduced printing or no printing treatment to reduce dye consumption from the source. The waterless printing and dyeing process uses supercritical carbon dioxide, organic solvents, or special non-aqueous media as dye carriers, and the entire process is carried out in a closed loop. S5: Integrated closed-loop recycling and reuse of non-aqueous media and dyes: Collect the undyed residual dye and waste non-aqueous media carrying dye in the S4 process, and send them to the media regeneration device. They are purified and refined through a coupling process of distillation, filtration and membrane separation. The purified non-aqueous media is recycled to the S4 waterless printing and dyeing process. The residual dye is purified and compounded and reused in printing production. S6: Closed-loop coupling of solid waste and waste heat throughout the entire process: All the cutting scraps and defective recycled fabrics generated in the S4 printing process are recycled back to the S1 process, constructing an internal recycling system for fabric solid waste; the waste heat exchange channel between the recycling preparation process and the waterless printing and dyeing process is opened up, and the waste heat from the high-temperature operation of waterless printing is used to heat the fabric recycling, solvent distillation, and reactor operation. The waste heat from the recycling process is used to preheat the greige fabric and non-aqueous media in reverse, realizing a two-way energy-saving closed loop; S7: Finished product inspection and packaging: Conduct performance and appearance inspections on the finished fabrics that have completed waterless printing and dyeing, and pack and store them in the warehouse after they pass the inspection.

2. The waterless printing and dyeing closed-loop production and waste fabric recycling process according to claim 1, characterized in that, The chemical recycling process of pure polyester waste fabrics in S2 includes: performing alcoholysis on pretreated waste polyester fabrics to generate an alcoholysis solution containing diethyl terephthalate; simultaneously carrying out decolorization and purification treatment on the alcoholysis solution, followed by cooling, crystallization, filtration, and drying to obtain high-purity diethyl terephthalate monomer; polymerizing the monomer to prepare recycled polyester chips, and finally obtaining high-performance recycled polyester fibers through melt spinning.

3. The waterless printing and dyeing closed-loop production and waste fabric recycling process according to claim 2, characterized in that, The alcoholysis reaction and decolorization treatment are completed continuously and in one integrated rotary reactor, using segmented temperature gradient precise control: the temperature inside the reactor is controlled not to exceed 200℃ to complete the fabric decolorization treatment, and the temperature is raised to above 200℃ to carry out the polyester alcoholysis reaction. No intermediate material transfer is required, realizing continuous integrated operation of decolorization and alcoholysis.

4. The waterless printing and dyeing closed-loop production and waste fabric recycling process according to claim 1, characterized in that, The chemical regeneration process of pure cotton waste fabrics in S2 includes: first, decolorizing and removing impurities from the pretreated pure cotton fabrics, then mechanically shredding them and precisely compounding them according to the degree of fiber polymerization to obtain standardized recycled pulp with a degree of polymerization of 350~550; then, using solvent dissolution to prepare a stable spinning solution from the recycled pulp, and finally obtaining high-toughness regenerated cellulose fibers through spinning and coagulation.

5. The waterless printing and dyeing closed-loop production and waste fabric recycling process according to claim 1, characterized in that, The chemical regeneration process for waste polyester-cotton blended fabrics in S2 includes: using a specific selective solvent to separate the components of the pretreated blended fabric, selectively dissolving the polyester component while completely preserving the cotton fiber component; the separated polyester component is then decolorized, alcoholized, polymerized, and spun to regenerate recycled polyester fiber; the separated cotton component is then purified, pulped, dissolved, and spun to regenerate recycled cellulose fiber.

6. The waterless printing and dyeing closed-loop production and waste fabric recycling process according to claim 1, characterized in that, The integrated recycling process of non-aqueous media and dyes in S5 is as follows: the undyed residual dye and waste non-aqueous media carrying dye discharged from the S4 process are first filtered to remove solid impurities, then the non-aqueous media and dye components are separated by distillation, and finally the non-aqueous media are deeply purified by membrane separation. The purity of the purified non-aqueous media meets the standards for recycling in anhydrous dyeing.

7. The waterless printing and dyeing closed-loop production and waste fabric recycling process according to claim 1, characterized in that, The entire production process adopts a separate recycling mode for water. Equipment cooling and micro-cleaning wastewater are fully reused after being deeply treated by ultrafiltration and reverse osmosis dual membrane processes. Concentrated water is treated by electrodialysis and triple-effect evaporation crystallization, and the crystallized salts are recycled as production aids.

8. The waterless printing and dyeing closed-loop production and waste fabric recycling process according to any one of claims 1 to 7, characterized in that, The process is compatible with two types of closed-loop implementation modes: the single-plant closed-loop mode realizes the internal recycling of solid waste, media, and waste heat in the plant area; the industrial park cluster closed-loop mode relies on the centralized treatment center to coordinate and integrate production resources to achieve clustered low-carbon closed-loop production in the park.

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