A method for preparing a sheet using recycled clothes and a mixing and drawing apparatus used in the method

Abstract

The present application discloses a method for preparing a sheet from recycled clothes and a mixing and drawing device used in the method. The method first tears and mixes the recycled clothes repeatedly to break the clothes into pieces and fibers. Then, the clothes pieces and fibers are partially softened by synchronous heating at a predetermined temperature. The temperature used is a temperature at which the materials of the clothes pieces can be softened. Next, according to the softened state of the clothes pieces and fibers, a recycled material that can or cannot be softened at the temperature is added to mix with the clothes pieces and fibers. Finally, the mixture is pressed into a sheet shape and cooled synchronously to obtain a sheet containing a large amount of fibers.

Description

Technical Field

[0001] This invention relates to the field of nonwoven fabric technology, and in particular to a method for preparing nonwoven fabric sheets using recycled garments and a closed-loop mixing and stretching device for its application. Background Technology

[0002] As is well known, the process of recycling and reprocessing garments into nonwoven fabrics typically involves steps such as crushing, drawing, loosening, finishing, and needle punching, ultimately producing nonwoven fabric. This process transforms discarded garments into other usable items, embodying the concept of environmental protection.

[0003] However, existing processes cause significant environmental pollution, including generating large amounts of lint and dust, and posing industrial safety and health management issues. Furthermore, the processes themselves are complex and inefficient. While garment recycling and reuse have environmental benefits, the environmental impact and efficiency problems in actual production processes indicate that existing technologies urgently need improvement. In the context of increasing societal focus on carbon emissions and sustainable development, developing a more environmentally friendly and efficient garment recycling and remanufacturing technology is particularly important. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing nonwoven fabric sheets using recycled garments. This method is not only different from existing nonwoven fabric manufacturing processes, but also features simple processing, energy saving and carbon reduction, significantly reducing environmental pollution and avoiding common problems such as lint, dust and industrial safety issues in traditional processes. It has significant environmental protection and practical value.

[0005] To achieve the above-mentioned technical objectives and effects, this invention discloses a method for preparing sheets using recycled garments, comprising at least the following steps:

[0006] Synchronous pulling and heating: The recycled garment is broken into fragments and filaments by repeated pulling and mixing, and then simultaneously heated at a predetermined temperature to soften the garment fragments and filaments. The recycled garment does not contain any metal parts, and the predetermined temperature is the softening temperature of the recycled garment.

[0007] Adjusting the softening state: Based on the softening state of garment scraps and fibers, add a predetermined recycled material that can be softened or not softened at the predetermined temperature, and subject the recycled material to repeated tearing and heating, so as to mix it with the garment scraps and fibers that are in a partially softened state;

[0008] Specifically, when the softened proportion of garment scraps and fibers is greater than the unsoftened proportion, a predetermined proportion of non-softened recyclable material is added; when the unsoftened proportion of garment scraps and fibers is greater than the softened proportion, a predetermined proportion of softenable recyclable material is added, wherein the recyclable material is polymer waste.

[0009] Cold pressing: A mixture of partially softened garment material, recycled material scraps, and fiber filaments is pressed into a sheet for output. The pressing process is simultaneously cooled to obtain a sheet with numerous fiber filaments.

[0010] Preferably, the steps of "synchronous mixing and heating" and "adjusting the softening state" are carried out in a closed space.

[0011] Preferably, the steps of "synchronous mixing and heating" and "adjusting the softening state" are carried out in a semi-open space.

[0012] The enclosed space is a cylinder, which is open at the top and side. Inside the cylinder are two heating elements and several breaking elements.

[0013] It also includes an extrusion component, which is movably disposed at the top opening of the cylinder. The two heating elements rotate relative to each other and are spaced appropriately, so that garment scraps, fibers, and recycled materials are compressed as they pass between the two heating elements. The tearing and pulling elements are disposed at an appropriate distance from the outside of the two heating elements. The extrusion component applies and releases pressure on the garment scraps, fibers, and recycled materials, so that the garment scraps, fibers, and recycled materials are continuously subjected to tearing and pulling by the tearing and pulling elements and the two heating elements, and then continuously fed into the space between the two heating elements for compression and output, and then into the space between the tearing and pulling elements and the two heating elements.

[0014] In the step of "adjusting the softening state", at the predetermined temperature, the proportion of softenable or non-softenable recyclable materials is adjusted so that the proportion of softened and unsoftened garment scraps and fibers is close to the same.

[0015] At the predetermined temperature, the recyclable materials that can be softened include waste materials of PE, PVB and / or EVA polymers, and the recyclable materials that cannot be softened at the predetermined temperature include waste materials of cotton, nylon and / or PET polymers.

[0016] Preferably, in the "cold pressing" step, a tablet press is used to press the partially softened mixture of garment scraps, fibers and recycled materials into tablets for output. The pressing part of the tablet press is in low-temperature contact with the mixture of garment scraps, fibers and recycled materials.

[0017] Most of the fibers produced are nonwoven fabric sheets.

[0018] Furthermore, this invention also discloses a mixing and stretching device used in a method for preparing sheet bodies from recycled garments. This device is used in the aforementioned steps of "synchronous mixing and stretching and heating" and "adjusting the softening state," and includes:

[0019] The cylinder, with an opening at the top and side, is used to hold garments and recycled materials;

[0020] Two heating elements are rotatably disposed opposite each other inside the cylinder, and the garment and recycled material passing between them are squeezed and heated relative to each other;

[0021] Several tearing elements are arranged at appropriate distances on the outside of two heating elements, each having an operating surface. These operating surfaces are inclined relative to the surfaces of the two heating elements, causing tearing of the garment and recycled material passing between each tearing element and the two heating elements;

[0022] The extrusion component is reciprocally movable at the top opening of the cylinder. Its movement direction corresponds to the tearing component and the two heating components. It can reciprocate to apply pressure and release pressure on the garment and recycled material fragments and fibers. After the garment and recycled materials are continuously torn by the tearing components and the two heating components, they are continuously fed into the space between the two heating components to be squeezed and output into the space between the tearing components and the two heating components, which promotes the uniform mixing of the partially softened garment fragments, fibers and recycled materials.

[0023] Furthermore, the present invention also discloses a mixing and stretching device used in a method for preparing sheet bodies from recycled garments. This device is used in the steps of "synchronous mixing and stretching and heating" and "adjusting the softening state," and includes:

[0024] A conveying device, comprising a tube body, the semi-open space being the interior of the tube body, wherein recycled garments are input from one end of the conveying device and garment debris and fiber filaments are output from the other end of the conveying device;

[0025] Several tearing and pulling components are disposed inside the tube to tear recycled garments and soft or non-soften recycled materials into fragments and fibers;

[0026] Several heating elements are disposed within the tube to heat passing garments, recycled material scraps, and fiber filaments at different temperatures; and

[0027] Multiple inspection windows, openable and located on one side of the tube, allow observation of garment debris and fiber softening status at different locations within the tube. These windows also allow input of softenable or non-soften recyclable materials. This invention offers the following advantages:

[0028] This invention provides a method for preparing nonwoven sheets using recycled garments, which has significant environmental and practical value. Compared with traditional nonwoven fabric manufacturing processes, this method simplifies the production steps. By simultaneously mixing and heating, adjusting the softening state, and cold pressing, it effectively avoids environmental pollution problems such as lint and dust generated in traditional processes. Furthermore, this method is carried out in a closed or semi-open space, reducing pollution to the surrounding environment while achieving energy conservation and carbon reduction. Because garment scraps and fibers are mixed with recycled materials in a partially softened state, the final sheet has excellent physical properties and can be used in various application scenarios, replacing traditional materials and promoting the resource utilization of waste.

[0029] The mixing and stretching equipment provided by this invention is particularly suitable for the aforementioned method of preparing garment sheets from recycled garments. Its design is reasonable, its operation is simple, and it can effectively improve production efficiency and material utilization. The equipment includes a closed or semi-open mixing and stretching device with heating elements, tearing elements, and extrusion elements, enabling continuous tearing, mixing, and extrusion of garment debris and fibers. In particular, the equipment design allows for material softening and mixing within a controlled environment, reducing health risks to operators and environmental pollution. Furthermore, the softening state of the material can be easily monitored through an inspection window, ensuring the stability of the production process and the consistency of product quality. The application of this equipment not only improves the recycling efficiency of waste but also promotes the development of sustainable production methods. Attached Figure Description

[0030] Figure 1 This is a flowchart of the garment recycling method for preparing sheets according to the present invention.

[0031] Figure 2 This is a schematic diagram of the structure of the closed mixing equipment of the present invention.

[0032] Figure 3 This is a schematic diagram of the semi-open mixed-pulling device structure of the present invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments.

[0034] Example 1

[0035] like Figure 1 , 2 As shown, this invention discloses a method 100 for preparing a sheet using recycled garments. The sheet produced is a nonwoven fabric, and includes the following steps:

[0036] The first step is synchronous mixing and heating 110: the recycled garment is placed in a closed space, and through repeated crushing, tearing and mixing, the recycled garment is broken into fragments and fibrous strands, and simultaneously heated at a predetermined temperature to partially soften the garment fragments and fibrous strands. The recycled garment does not contain any metal parts, and this temperature is the temperature at which some of the garment's materials can soften. Specifically, the synchronous mixing and heating 110 is implemented using a closed mixing device 10, which includes a cylinder 12, two heating elements 13 and 14, multiple breaking and pulling elements 15, and an extrusion element 16.

[0037] The cylinder 12, with an opening at the top and sides, is used to hold garments. These are recycled garments without metal accessories, including the garment body and accessories made of polymer materials such as buttons, plastic zippers, labels, collar films, linings, GORE-TEX waterproof and breathable membranes, and non-removable leather jackets.

[0038] Two heating elements 13 and 14 are rotatably (rotating in the same or opposite directions, depending on the material characteristics of the garment or the difficulty of crushing or grinding) arranged opposite each other in the cylinder 12 and connected to an electric heating device (not shown in the figure). Each element consists of a shaft 22 and an action part 24. The two ends of each shaft 22 are mounted on both sides of the cylinder 12, and one end of each shaft 22 is connected to a power drive device (such as a motor, not shown in the figure) to drive the rotation, thereby squeezing and heating the garment passing between them.

[0039] Several tearing components 15, each an irregularly shaped block, are positioned at appropriate intervals outside the two heating elements 13 and 14 within the cylinder 12. This allows the garment to be torn as it passes between the tearing components 15 and the two heating elements 13 and 14 through their combined action. Each tearing component 15 has a corresponding action surface 26 on one of the two heating elements 13 and 14. Each action surface 26 is inclined relative to the surfaces of the two heating elements 13 and 14, but is not limited to this. The gap between each action surface 26 and the surfaces of the two heating elements 13 and 14 varies from large to small or from small to large (a small gap produces a tearing or stringing effect, while a large gap produces a mixed effect).

[0040] The extrusion member 16, in piston form, is driven by a hydraulic cylinder or a pneumatic cylinder and is positioned at the top opening of the cylinder body 12 (the stroke is adjustable, limited to not touching the tearing member 15). The first extrusion member 16 moves up and down and corresponds to the gap position between the two action members 13 and 14 to reciprocate and release pressure on the garment fragments and fibers, promote the tumbling of the garment fragments and fibers in the cylinder body 12, and make the garment and garment fragments and fibers continuously pass between the action surface 26 of each tearing member 15 and the two heating action members 13 and 14, and be torn or mixed, and then continuously input into the two heating action members 13 and 14 to be squeezed and output, and enter between each tearing member 15 and the two heating action members 13 and 14, promoting the uniform mixing of the partially softened garment fragments and fibers.

[0041] Of course, the mixing and drawing device 10 is not limited to having an extrusion member 16 on the top side of the cylinder 12. An extrusion member 16 may also be added to the bottom side and / or the left and right sides of the cylinder 12 to improve the effect of garment crushing, drawing and mixing. In addition, a discharge port (not shown in the figure) is added to the bottom side of the cylinder 12 to remove garment fragments and fibers in a partially softened state.

[0042] Since the main body of the garment is mostly made of polyester fiber or other plastic materials, or cotton, and the garment components or accessories are also made of various plastic materials, the aforementioned temperature refers to a temperature higher than the softening temperature of the main body of the garment and its components and accessories, falling between the heat distortion temperature and the melting point. In this embodiment, this temperature can be set to 120 degrees Celsius. This temperature is when most types of plastic materials have softened (heat-deformed) but not melted (temperature not reached the melting point), allowing the recycled material debris and fibers to be partially softened for subsequent processing. Similarly, this temperature setting and adjustment can be increased or decreased according to the different compositions of the recycled garment.

[0043] In other words, the 110 steps of synchronous mixing and heating can integrate multiple steps such as garment crushing, drawing, cotton loosening, and cotton finishing in the traditional process of recycling and reprocessing garments into nonwoven fabrics into one step.

[0044] The second step is to adjust the softening state 120: according to the softening state of garment scraps and fibers, add the predetermined recycled material that can be softened or not softened at this temperature into the space, so that the recycled material can be repeatedly crushed, torn and heated, and mixed with the garment scraps and fibers that are in a partially softened state.

[0045] When the proportion of softened garment scraps and fibers is greater than the proportion of unsoftened scraps, a predetermined proportion of non-softened recyclable material is added; when the proportion of unsoftened garment scraps and fibers is greater than the proportion of softened scraps, a predetermined proportion of softenable recyclable material is added. This recyclable material is polymeric waste, such as PE, PVB, EVA, cotton, nylon, and PET, but is not limited to these. The proportion of softenable or non-softened recyclable material added at this temperature is intended to bring the proportion of softened to unsoftened garment scraps and fibers to approximately the same level, but is not limited to these.

[0046] Furthermore, to ensure that subsequent steps produce nonwoven fabrics with a high proportion of fibers, adjustments must be made based on the partial softening state of the garment debris and fibers generated during the simultaneous mixing and heating step 110. For example, when the softened and unsoftened proportions of garment debris and fibers are approximately equal (around 50% each), this is the optimal ratio for producing nonwoven fabric in subsequent steps (with approximately equal amounts of fiber and bonded fiber portions), and no adjustment to the partial softening state of the garment debris and fibers is necessary. However, when the softened proportion of garment debris and fibers is approximately 30% and the unsoftened proportion is approximately 70%, it indicates that the unsoftened proportion is too high. This will result in the nonwoven fabric produced in subsequent steps having too much fiber and too little bonded fiber, leading to a nonwoven fabric structure that is too loose and prone to breakage.

[0047] At this point, 20% to 40% of the recycled material that can be softened at this temperature (such as the aforementioned PE, PVB, EVA, etc., which can be softened or melted at 120 degrees Celsius) can be added to the mixing and stretching equipment 10 for tearing and mixing, so that the softened and unsoftened ratio of the garment and the mixture of recycled material scraps and fiber filaments can be nearly equal.

[0048] When the softened proportion of garment scraps and fibers is approximately 80% and the unsoftened proportion is approximately 20%, it indicates that the softened proportion is too high. This will result in the nonwoven fabric produced in subsequent steps having too little fiber content and too much bonded fiber content, making it resemble a nonwoven fabric. In this case, 30% to 50% of recycled materials that cannot soften at this temperature (such as the aforementioned cotton, nylon, and PET, which are not yet softened at 120 degrees Celsius) can be added to the closed mixing and drawing equipment 10 for tearing and mixing, so that the softened and unsoftened proportions of the garment and recycled material scraps and fiber mixture can be made approximately equal.

[0049] The final step is cold pressing 130: The mixture of garment scraps, recycled material fragments, and fibers, which has been softened and adjusted, is taken from the mixing and stretching equipment 10 and pressed into a sheet shape using a sheet press (not shown in the figure). The pressing process is accompanied by simultaneous cooling to obtain a sheet with numerous fibers, i.e., nonwoven fabric. The sheet press is a two-roller type, with the pressure applied by the two rollers. The partially softened garment scraps, fibers, and recycled material mixture are fed between these two rollers and pressed out. These two rollers are connected to a low-temperature cooling device (not shown in the figure; its technology is similar to known connections to heating devices and is therefore known and will not be elaborated here). This device simultaneously cools and shapes the garment scraps and fibers while they are pressed into a sheet, resulting in a nonwoven fabric of uniform quality. This can replace the cotton-loosening and needle-punching steps in the traditional garment recycling and nonwoven fabric production process.

[0050] The method for preparing nonwoven fabrics using recycled garments as described in this invention, through simultaneous mixing, heating, softening adjustment, and cold pressing, not only differs from the traditional process of recycling garments into nonwoven fabrics, but also maintains consistent quality, simplifies the process, achieves energy-saving and carbon-reducing effects, and can manufacture nonwoven fabrics in a closed-loop environment, significantly reducing pollution to the surrounding environment. It avoids the highly polluting cotton lint, dust, and industrial safety management issues associated with the traditional garment recycling process, and has significant environmental and practical value.

[0051] Example 2

[0052] like Figure 3 As shown, this is another preferred embodiment of the present invention, the steps of which are generally the same as the preparation method disclosed in Example 1, except that:

[0053] In this embodiment, in the method 100 for preparing sheets using recycled garments, the simultaneous mixing and heating step 110 and the softening state adjustment step 120 are performed in a semi-open space, such as... Figure 3 Another mixing device 30 is shown. This mixing device 30 also includes the aforementioned breaking member 15, but it includes a conveying device 32, multiple heating elements (not shown) and multiple inspection windows 34.

[0054] The conveying device 32 includes a tube 40, which forms a semi-open space inside. Recycled garments are input from one end of the tube 40 and output from the other end. The conveying device 32 can be a known type of screw conveyor with an internal conveying screw, but is not limited to this, as long as it can move and output the recycled garments. Various tearing elements 15 are arranged inside the tube 40. When the recycled garments are moved by the conveying device 32, they can be torn into fragments and fibers by passing through these tearing elements 15.

[0055] Several heating elements are arranged at different positions on the inner wall of the tube 40, which can heat garments, recycled material scraps, and fibers passing through the corresponding positions of different heating elements at different temperatures. These heating elements are roughly similar to the heating devices in known tunnel-type rubber foam ovens and ovens, which are known technologies and will not be described in detail here.

[0056] Several inspection windows 34, each consisting of an openable and closable frame and a piece of glass (not shown in the figure), are detachably mounted on the top side of the tube 40. These windows allow observation of garment debris and fiber softening at different locations within the tube 40, and can be opened to allow the introduction of softenable or non-soften recyclable materials. These inspection windows 34 are largely similar to the inspection windows used in various production equipment for monitoring production status and are considered known technology, so they will not be described in detail here.

[0057] During the synchronous mixing and heating step 110 and the softening state adjustment step 120, when using the mixing and pulling equipment 30, the recycled garments are input into the conveying device 32 from one end of the tube 40. As the garments move, they are repeatedly torn into fragments and fibers by the various tearing components 15 inside the conveying device 32, and simultaneously heated by the various heating components, causing the garment fragments and fibers to partially soften. Workers can inspect the softening state of the garment fragments and fibers inside the conveying device 32 through various inspection windows 34, and can also input predetermined softenable or non-softenable recycled materials into the conveying device 32 through these inspection windows 34.

[0058] Furthermore, the number of each breaking element 15 gradually decreases from the garment input end of the tube 40 to the other end to ensure that the garment can be completely broken down into fragments and fibrous strands. Secondly, the heating temperature of each heating element gradually increases from the garment input end of the tube 40 to the other end. That is, the heating temperature of the heating element near the garment input end of the tube 40 is lower (e.g., 50 degrees Celsius), while the heating temperature of each heating element arranged towards the other end of the tube 40 gradually increases (e.g., the heating temperature of the heating element on the top side of the inner wall of the tube 40 can be increased from 120 degrees Celsius to 180 degrees Celsius, and the heating temperature of the heating element on the bottom side of the inner wall of the tube 40 can be increased from 120 degrees Celsius to 250 degrees Celsius, but is not limited to this).

[0059] Furthermore, multiple monitoring devices, such as monitoring lenses or pressure sensing components, can be installed inside the tube 40 to monitor the softening state of garment debris and fibers at different locations inside the tube 40. (When the debris and fibers of recycled garments and recycled materials are softened, the pressure value detected by the pressure sensing component is low, which can be used to determine that the debris and fibers of recycled garments and recycled materials have softened; conversely, a higher pressure value indicates that the debris and fibers of recycled garments and recycled materials have not softened or have not softened most of them.)

[0060] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing sheet bodies using recycled garments, characterized in that, Include at least the following steps: Synchronous mixing and heating: By repeatedly tearing and mixing, the recycled garment is broken into fragments and fibrous strands, and then simultaneously heated at a predetermined temperature to partially soften the garment fragments and fibrous strands. The recycled garment does not contain any metal accessories, and the predetermined temperature is the softening temperature of the recycled garment's partial materials. Adjust the softening state: Based on the softening state of garment scraps and fibers, a predetermined recycled material that can be softened or not softened at the predetermined temperature is added, and the recycled material is subjected to repeated tearing and heating, and mixed with the garment scraps and fibers in a partially softened state. Among them, when the softened proportion of garment debris and fiber filaments is greater than the unsoftened proportion, a predetermined proportion of unsoftened recyclable materials is added. When the proportion of unsoftened garment scraps and fibers is greater than the proportion of softened ones, a predetermined proportion of softenable recyclable material is added, wherein the recyclable material is polymer waste. And cold pressing: The partially softened garment is pressed into a sheet by mixing it with recycled material scraps and fibers. The pressing process is carried out simultaneously with cooling to obtain a sheet with numerous fibers.

2. The method for preparing sheet bodies using recycled garments as described in claim 1, characterized in that, The steps of synchronous mixing, heating, and adjusting the softening state are carried out in a closed space.

3. The method for preparing sheet bodies using recycled garments as described in claim 1, characterized in that, The steps of synchronous mixing, heating, and adjusting the softening state are carried out in a semi-open space.

4. The method for preparing sheet bodies using recycled garments as described in claim 2, characterized in that, The enclosed space is a cylinder, which is open at the top and side. Inside the cylinder are two heating elements and several breaking and pulling elements. It also includes an extrusion component, which is movably disposed at the top opening of the cylinder. The two heating elements rotate relative to each other and are spaced appropriately, so that garment scraps, fibers, and recycled materials are compressed as they pass between the two heating elements. The tearing and pulling elements are disposed at an appropriate distance from the outside of the two heating elements. The extrusion component applies and releases pressure on the garment scraps, fibers, and recycled materials, so that the garment scraps, fibers, and recycled materials are continuously subjected to tearing and pulling by the tearing and pulling elements and the two heating elements, and then continuously fed into the space between the two heating elements for compression and output, and then into the space between the tearing and pulling elements and the two heating elements.

5. A method for preparing sheet bodies using recycled garments as described in claim 2 or 3, characterized in that, In the step of adjusting the softening state, at the predetermined temperature, the proportion of softenable or non-soften recyclable materials is adjusted so that the proportion of softened and unsoftened garment scraps and fibers is approximately the same.

6. A method for preparing sheet bodies using recycled garments as described in claim 2 or 3, characterized in that, At the predetermined temperature, the softenable recyclable materials include waste materials of PE, PVB and / or EVA polymers, and the non-softening recyclable materials at the predetermined temperature include waste materials of cotton, nylon and / or PET polymers.

7. A method for preparing sheet bodies using recycled garments as described in claim 2 or 3, characterized in that, In the cold pressing step, a tablet press is used to press the partially softened mixture of garment scraps, fibers and recycled materials into tablets for output. The pressing part of the tablet press is in low-temperature contact with the mixture of garment scraps, fibers and recycled materials.

8. The method for preparing sheet bodies using recycled garments as described in claim 1, characterized in that, Most of the prepared fiber sheets are nonwoven fabrics.

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