WO2024098139A1

WO2024098139A1 - Methods of reclaiming textile waste and recycling it without dyeing nor creating microplastic contamination in water system

Info

Publication number: WO2024098139A1
Application number: PCT/CA2023/051480
Authority: WO
Inventors: Sae CHANG
Original assignee: Heat-Mx Worldwide
Priority date: 2022-11-08
Filing date: 2023-11-07
Publication date: 2024-05-16

Abstract

The present technology relates to methods of recycling textile waste from various sources without putting the textile through dyeing and all its related processes such as bleaching, whitening, fixing, etc., nor creating microplastic contamination in water system. In addition, the present technology relates to methods of enabling the recycling of the formerly undesired process waste from various manufacturing sources, e.g., cut-and-sew-process, etc., with the above-mentioned principal, i.e., no dyeing or dyeing-related processes, in various compositions of 100% synthetic and blends of synthetic fibers.

Description

METHODS OF RECLAIMING TEXTILE WASTE AND RECYCLING IT WITHOUT

DYEING NOR CREATING MICROPLASTIC CONTAMINATION IN WATER SYSTEM

FIELD OF TECHNOLOGY

[001] The present technology relates to methods of recycling textile waste from various sources without putting the textile through dyeing and all its related processes such as bleaching, whitening, fixing, etc., nor creating microplastic contamination in water system. In addition, the present technology relates to methods of enabling the recycling of the formerly undesired process waste from various manufacturing sources, e.g., cut-and-sew- process, etc., with the above-mentioned principal, i.e., no dyeing or dyeing-related processes, in various compositions of 100% synthetic and blends of synthetic fibers.

BACKGROUND

[002] Unlike plastics, textile waste almost invariably contains a large quantity of chemicals, such as dyes, fixing agents, whitening agents, etc. Therefore, textile waste provides much more harm for the environment, in general, than plastic waste as the toxic chemicals in textile waste leak into the soil, then contaminate our water system or spread through the air when buried underground or burnt.

[003] Textile waste is created from a wide range of sources as indicated below: (Process waste) During the courses of manufacturing in various forms of textile intermediary and finished goods, such as fibers, yarns, fabrics, finished merchandise, etc., waste is created during the manufacturing processes. The quantity of the waste varies depending on how each process is setup. In traditional cut-and-sew factories, where finished merchandises for consumption, for example, approx. 5 ~ 20% of fabric waste can be created after the cutting process where the desired areas for the design patterns are obtained. Another example of the (Process Waste) is found in manufacturing processes of non-woven fabrics. In general, the quality of non-woven fabrics in both edges, coming off a nonwoven manufacturing machine, is of an inconsistent quality, e.g., varying densities of fibers, weights, etc., and the part is generally considered as process waste. With this, a certain quantity of the edge portions is cut off and only the middle portion of the non-woven fabric with more consistent quality is shipped for further processing. There may be some limited areas where such process waste can be reclaimed without harming environment, e.g., used as filling material for low-quality stuffed animals, etc. However, the quantity required for such application is much smaller than the quantity of waste itself. With this, other methods including burning it off through incineration or burying it underground, are adopted to dispose the waste and it creates a lot of harmful impact on the environment. Post-consumption waste) All people, even newly born babies, consume a lot of textile goods and consequently, generate a lot of waste. Although a majority of people think that the waste they create are properly recycled when they put the unwanted items in local recycling bins. But, it is far from the reality according to the results of a wide range of studies, reports, etc., published on the subject all over the world. Unfortunately, a large portion of the consumed textile waste gets shipped to 3^rd world countries in Asia, Africa, etc., then gets buried underground or burnt. As in the explanations provided above under the (Process Waste), the textile waste from households, industrial usages, etc., contain enormous quantities of toxic chemicals and harm our environment when buried underground or burnt.

[004] Textile waste consists of a wide range of material compositions, colors, etc., and it makes difficult to find ways of upcycling and/or recycling them as most consumers refuse to buy items with undesired color, texture, etc.

[005] Conventional ways of recycling in commercial volumes almost invariably deals only with plastic waste rather than textile material and create many different sources of harmful impacts for the environment. To name a few, a large quantity of microplastic is created from mechanically heavy processes such as crushing, chopping, cutting, slicing, etc., large quantities and variety of toxic chemicals such as dyes, whitening agents, etc., are used for colorizing recycled material, inefficient transportation for shipping material across the international oceans is created, etc., among many other. SUMMARY OF TECHNOLOGY

[006] According to one aspect, the present technology relates to a method for converting thermoplastic synthetic material to fibers, the method comprising: i) melting the thermoplastic synthetic material to a temperature above the melting temperature of the thermoplastic synthetic material to obtain an emulsion of polymers, ii) extruding the emulsion of polymer into fibers at a temperature above the melting temperature of the thermoplastic synthetic material, wherein extrusion of the emulsion of polymer results into fibers. In some aspects, the thermoplastic synthetic material is a textile waste. In some aspects, the thermoplastic synthetic material is converted to fibers without the use of a dyeing process. In some aspects, the thermoplastic synthetic material is converted to fibers without creation of microplastics. In some aspects, the synthetic material is homogenous. In some aspects, the synthetic material is polypropylene (PP).

[007] According to some aspects, the present technology relates to a method for converting a blend of thermoplastic synthetic materials to a non-woven structure, the method comprising: i) melting the blend of thermoplastic synthetic materials to a temperature above the melting temperature of the blend of thermoplastic synthetic materials to obtain a web of polymer emulsion, ii) applying the web of polymer emulsion onto a conveyer belt; and iii) cooling the web of polymer that has been through the conveyer to generate a non-woven structure. In some aspects, the blend of thermoplastic synthetic material is a textile waste. In some aspects, the blend of thermoplastic synthetic material is converted to a non-woven structure without the use of a dyeing process. In some aspects, the blend of thermoplastic synthetic material is converted to a non-woven structure without creation of microplastics. In some aspects, the blend of thermoplastic synthetic material comprises polyethylene (PET) and polypropylene (PP). In some aspects, the blend of thermoplastic synthetic material comprises 65% PET and 45% PP.

[008] According to one aspect, the present technology relates to, textile material, composed specifically of synthetic material, i.e. , petroleum based thermoplastic material, reclaimed through the specific process standards, which mainly consist of melting method, named as CLEAN RECYCLING INITIATIVE™, is reprocessed and used for the applications where visual appeal is not important. A goal of the present technology is to avoid the dyeing and all its related process where large quantities of toxic chemicals such as dyes, fixing agents, whitening agents are used. Such examples include, but not limited to, thermal insulation used in the structure of being sandwiched with other fabrics and/or other types of material in apparel, construction, etc., noise cancelling for electronics, vehicles, airplanes, etc., needle punched non-woven for reinforcement under other layers of fabrics, etc., among many other.

[009] The present technology relates to methods of converting thermoplastic synthetic material made up of 100% homogeneous material, e.g., polyester, polypropylene, nylon, acrylic, etc., into fibers which can be used in subsequent applications mentioned above, using primarily melting method above the melting temperature of each fiber type. For example, heating fiber, yarn, fabric, etc., with 100% polyester above its melting temperature enables the polymer to be further processed under different methods, e.g., extrusion into fibers, solidifying the polymer into chips, forming a web of polymer emulsion on a conveyer belt as a sheet (hereafter melt-web process), etc.

[010] The present technology also relates to methods of converting thermoplastic synthetic material made up of blended compositions, i.e., polyester/nylon blends, polyester/polypropylene blends, etc. The temperature range of melting and crystallinity amongst the blended fibers determine the feasibility of this method. For example, a blend of polymers which can coexist in the melted emulsion form with the densities satisfying subsequent processes, such as extrusion into fibers, forming a melt-web of polymer emulsion, etc., enables the fabrication of an intermediary material for different applications.

[011] According to one aspect, the present technology relates to melt-blown non-woven insulation material is made of 100% homogeneous synthetic material, e.g., 100% Polypropylene which satisfies both performance requirements for target applications, e.g., thermal insulation, etc., and enabling the process of bringing and putting the edge parts back to the polymerization process in the beginning of the process line. Thermal insulation material made with the melt-blown process in the market, in particular, is blended with two different types of synthetic fibers, namely Polyester and Polypropylene. In some embodiments, the present technology is to use only one type of fibers and/or polymers in order to enable the edge-recycling process described above. The polypropylene fibers required in the form of filament and staple fibers must be in the similar range of melting temperature and melt flow behavior index in order to process it without creating settlement in polymer tank or blockage in the process line.

[012] The present technology relates to methods of creating a web of polymer emulsion onto a conveyer belt and allow it to cool down to create a non-woven structure, then wind it for subsequent processes. As previously mentioned above, this process is called meltweb. The process may be used for either 100% homogeneous synthetic material or blended synthetic material.

BRIEF DESCRIPTION OF THE DRAWINGS

[013] Further aspects and advantages of the present technology will become better understood with reference to the description in association with the following Figures, in which similar references used in different Figures denote similar components, wherein:

[014] FIG. 1 is an illustration of both desired and undesired areas, a.k.a., process waste created during a cut-and-sew process of an apparel-making. Process waste is created during virtually every manufacturing process, e.g., manufacturing processes of fiber, yarn, fabric and finished merchandise: and

[015] FIG. 2 is a diagram of the system where the feeding of the source waste material, polymerization and polymer extrusion is illustrated: and

[016] FIG. 3 is a diagram of a spunbond non-woven manufacturing process: and

[017] FIG. 4 is a diagram of a melt-blown non-woven manufacturing process

[018] FIG. 5 is a diagram of a melt-web non-woven manufacturing process: and

[019] FIG. 6 is a diagram of the edge parts from all non-woven manufacturing process

DETAILED DESCRIPTION OF TECHNOLOGY [020] With reference to the drawings, the preferred embodiments of the present technology will be herein described for indicative purpose and by no means as of limitation. Desired areas for garment making from a cut-and-sew process. Numeric references for FIG. 1 to FIG 6. are as follows:

1 Desired areas for garment making from a cut-and-sew process

2 Undesired areas for garment making from a cut-and-sew process, i.e. , an example of a process waste described in the current invention

3 Enclosed waste material feeding chamber

4 Feeder consisting of material shredding I cutting mechanism(s) to reduce the mass of the material entering the polymerization tank (5)

5 Polymerization tank

6 Temperature control

7 Mixers

8 Extrusion

9 Solidification into fibers or chips

10 Polymer hopper (Spunbond process)

11 Extruder drive (Spunbond process)

12 Polymerization tank & Extruder (Spunbond process)

13 Filter (Spunbond process)

14 Pump (Spunbond process)

15 Spin pack (Spunbond process)

16 Quench air (Spunbond process)

17 Attenuation (Spunbond process)

18 Forming belt (Spunbond process) Compaction roll (Spunbond process)

Calendar (Spunbond process)

Winder (Spunbond process)

Guide roll (Spunbond process)

Edge guide (Spunbond process)

Polymer hopper (Melt-blown process)

Polymerization tank & Extruder (Melt-blown process)

Gear pump (Melt-blown process)

Extrusion tank (Melt-blown process)

Hot air (Melt-blown process)

Non-woven web (Melt-blown process)

Collecting belt (Melt-blown process)

Calendar (Melt-blown process)

Winder (Melt-blown process)

Polymer hopper (Melt-web process)

Polymerization tank & Extruder (Melt-web process)

Gear pump (Melt-web process)

Extrusion tank (Melt-web process)

Extrusion (Melt-web process)

Oscillating weight distributor (Melt-web process)

Collecting belt (Melt-web process)

Calendar (Melt-web process)

Winder (Melt-web process) 42 Original width of the wound material

43 Finished width of the wound material

44 Edge parts

[021] Undesired areas for garment making from a cut-and-sew process, i.e., an example of a process waste described in the current invention

[022] Referring to FIG 1., an example of the undesired material as in process waste generated from various processes of textile manufacturing is shown. As an example, it is the area where the fabrics is cut into the patterns for the subsequent sewing process. This type of process waste may be created in most of textile manufacturing processes, including but not limited to the manufacturing processes of fibers, yarns, fabrics, etc. These materials are in varying qualities such as different material compositions, colors, weights, textures, etc. One of the important characteristics of these materials is that they are in separate pieces and it is hence much easier to segregate them from one type of fiber composition to another, in comparison with segregating different material after it is sewn in together with other components of finished merchandise. The present technology relates to methods for reclaiming the waste in the easiest possible way by collecting the materials in the same fiber compositions in this process.

[023] Referring to FIG 2., an example of a system where a certain type of raw material as waste, e.g., fiber, yarn, fabric, etc., with a certain fiber composition, comprising of synthetic fibers is fed, polymerized, then fed to the process where either fibers are extruded or converted into another form of intermediary material, e.g., pellets or chips, for further processing as described above.

[024] Referring to FIG 3., it illustrates the subsequent processes after the polymerization if the polymer is converted into pellets or chips described as described above. The equipment uses the pellets or chips obtained from the prior processes described above as the source material, then turns it into a spunbond non-woven material.

[025] Referring to FIG 4., it illustrates the subsequent processes after the polymerization if the polymer is converted into pellets or chips described above. The equipment uses the pellets or chips obtained from the prior processes as described above as the source material, then turns it into a melt-blown non-woven material.

[026] Referring to FIG 5., it illustrates the subsequent processes after the polymerization if the polymer is converted into pellets or chips as described above. The equipment uses the pellets or chips obtained from the prior processes as described above as the source material, then turns it into a melt-web non-woven material.

[027] Referring to FIG 6., it illustrates the cutting and winding process of non-woven fabric manufacturing and the process waste generated on the edges due to inconsistent qualities.

[028] In one embodiment, the present technology relates to a method of reclaiming textile waste made with synthetic material, generated through a wide range of sources, including but not limited to, post-consumption, process waste, etc., then converting it into an intermediary material through the means of melting method, avoiding dyeing and all its related processes for the purpose of eliminating microplastic contamination in water and use of toxic chemicals. One of the main characteristics of the textile waste collected from different processes and sources described above is its diversity in colors. Before the present technology, the color variance made it limited to repurpose it in any application where the waste is reused in the exposed areas. However, the present technology makes it possible to repurpose the waste regardless of color variance as it is converted to applications where the reclaimed material will be used in unexposed areas, thus eliminating the needs for re-dyeing. Examples of such application include, but not limited to, the material used as insulation and felt-liners for apparel, building construction, noise cancellation for automotive, home appliances, etc.

[029] In one embodiment, the present technology relates to a method of converting polymerized emulsion, described as melt-web non-woven material in this document, composed of either 100% homogeneous synthetic composition or blended with two or more different polymer types in the temperature ranges which control the melt flow behavior of the involved polymer type(s) in such a way to form a web of melted polymer deposited onto a conveyer belt, then allowing it to cool down before winding it for the subsequent processes in order to obtain desired properties.

[030] A method of making non-woven fabric structure with 100% homogeneity for the purpose of polymerizing the edge areas and/or regular process waste within the same process. In particular, manufacturing melt-blown non-woven fabric consisting of polypropylene filament and polypropylene staple fibers with similar range of density and melt flow characteristics, replacing the blended composition of polypropylene and polyester in the products available in the current market.

Claims

CLAIMS:

1. A method for converting thermoplastic synthetic material to fibers, the method comprising: i) melting the thermoplastic synthetic material to a temperature above the melting temperature of the thermoplastic synthetic material to obtain an emulsion of polymers, ii) extruding the emulsion of polymer into fibers at a temperature above the melting temperature of the thermoplastic synthetic material, wherein extrusion of the emulsion of polymer results into fibers.

2. The method of claim 1 , wherein the thermoplastic synthetic material is a textile waste.

3. The method of claim 1 or 2, wherein the thermoplastic synthetic material is converted to fibers without the use of a dyeing process.

4. The method of any one of claims 1 to 3, wherein the thermoplastic synthetic material is converted to fibers without creation of microplastics.

5. The method of any one of claims 1 to 4, wherein the synthetic material is homogenous.

6. The method of claim 5, wherein the synthetic material is polyethylene (PET).

7. The method of claim 5, wherein the synthetic material is polypropylene (PP).

8. A method for converting a blend of thermoplastic synthetic materials to a nonwoven structure, the method comprising: i) melting the blend of thermoplastic synthetic materials to a temperature above the melting temperature of the blend of thermoplastic synthetic materials to obtain a web of polymer emulsion, ii) applying the web of polymer emulsion onto a conveyer belt; and iii) cooling the web of polymer that has been through the conveyer to generate a non-woven structure.

9. The method of claim 8, wherein the blend of thermoplastic synthetic material is a textile waste.

10. The method of claim 8 or 9, wherein the blend of thermoplastic synthetic material is converted to a non-woven structure without the use of a dyeing process.

11. The method of any one of claims 8 to 10, wherein the blend of thermoplastic synthetic material is converted to a non-woven structure without creation of microplastics.

12. The method of any one of claims 8 to 11, wherein the blend of thermoplastic synthetic material comprises polyethylene (PET) and polypropylene (PP).

13. The method of claim 12, wherein the blend of thermoplastic synthetic material comprises 65% PET and 45% PP.