METHOD FOR RECOVERING A TEXTILE MATERIAL CONTAINING CELLULOSE

Description

[0001] The invention relates to a method for reusing or recycling textile material containing cellulose.

[0002] Viscose fibers are synthetic or regenerated fibers produced using a wet spinning process known as the viscose process. The starting material for the viscose process is cellulose, which is derived from wood. From this wood, high-purity cellulose is obtained in the form of chemical pulp. In successive process steps, the pulp is first treated with sodium hydroxide, forming alkali cellulose. Subsequent reaction of this alkali cellulose with carbon disulfide produces cellulose xanthate. From this, the viscose spinning solution is created by adding more sodium hydroxide. This solution is pumped through nozzle holes into a spinning bath. There, coagulation forms a viscose filament in each nozzle hole. The resulting viscose filaments are then cut into viscose staple fibers.

[0003] Lyocell refers to a type of regenerated cellulose fiber produced using a direct solvent process. For the lyocell process, the cellulose is extracted from the raw material, wood. The resulting pulp can then be dissolved in N-methylmorpholine N-oxide (NMMO), a solvent, by dehydration without chemical modification, filtered, and subsequently extruded through spinnerets. After passing through an air gap in a bath of aqueous NMMO solution, the formed filaments are precipitated and then cut into staple fibers.

[0004] Traditionally, both the lyocell and viscose processes primarily use wood as raw material or wood pulp produced from it.

[0005] WO 2017 / 019802 A1 discloses a process and a system for processing mixed textile raw material, isolating (cellulose and polyester) molecules, and regenerating cellulose fibers and polyester fibers. As shown in the patent application, the process and system are described in the patent application. Figure 1 As can be seen, a mixture of textiles (e.g., old clothes) is separated into cotton blends and polyester blends after pretreatment.

[0006] The object of the present invention is to produce molded bodies containing cellulose in an efficient, sustainable and environmentally friendly manner.

[0007] This problem is solved by the subject matter according to the independent patent claim. Preferred embodiments are set forth in the dependent patent claims.

[0008] According to an embodiment of the present invention, a method for reusing (or recycling) cellulose-containing textile material to produce (in particular, cellulose-based) regenerated cellulosic molded bodies is provided, wherein in the method the textile material is shredded, at least a portion of the non-fiber components of the shredded textile material is separated from the fiber components of the shredded textile material, at least a portion of the non-cellulosic fibers of the fiber components is mechanically separated from the cellulosic fibers of the fiber components, at least a further portion of the non-cellulosic fibers is chemically separated from the cellulosic fibers, and the molded bodies are produced based on the cellulosic fibers after the mechanical separation and the chemical separation.

[0009] For the purposes of this application, the term "cellulose" can be understood to mean, in particular, an organic compound that is a component of plant cell walls or can be produced synthetically. Cellulose is a polysaccharide (i.e., a complex sugar). Cellulose is unbranched and typically contains several hundred to tens of thousands of β-D-glucose molecules (β-1,4-glycosidic linkage) or cellobiose units. Plants use cellulose molecules to build cellulose fibers in a controlled manner. Cellulose molecules can be aggregated using a technical process to form regenerated fibers, for example, as tear-resistant fibers.

[0010] Within the scope of this application, the term "molded body" can be understood to mean, in particular, a two- or three-dimensional geometric body that is a result of a process for producing or recovering cellulose. Specifically, a molded body can be understood to be a two- or three-dimensional object that contains or consists of cellulose and is produced from dissolved cellulose. Molded bodies can be, in particular, lyocell molded bodies, viscose molded bodies, or modal molded bodies. Typical molded bodies are filaments, fibers, sponges, and / or films. In principle, all types of cellulose molded bodies are suitable for embodiments of the invention. Fibers include both continuous filaments and cut staple fibers with conventional dimensions (for example, 38 mm in length) and short fibers.For the production of fibers, both processes with take-off devices after one or more extrusion dies and other processes, such as melt-blowing, are suitable. As an alternative to fibers, a cellulose-containing film can also be produced as a formed body, i.e., a flat and essentially homogeneous film with or made of cellulose. Films can be produced, in particular, by adjusting the process parameters of a lyocell process so that coagulation is triggered, at least partially, only after the filaments come into contact with a receiving surface. Films can be understood as flat cellulose formed bodies, the thickness of which is adjustable (for example, by selecting a number of serially arranged die bars). Other embodiments of a formed body include a woven fabric and a nonwoven fabric made of cellulose filaments, respectively.made of cellulose fibers, in particular a spunbond nonwoven fabric made of integrally fused ("merging") essentially continuous cellulose filaments ("melt blown"). A woven fabric can be understood to be, in particular, a textile sheet structure made of at least two (preferably perpendicular or nearly perpendicular) interlaced thread systems (or fiber systems), whereby threads (or fibers) in the longitudinal direction can be referred to as warp threads and threads (or fibers) in the transverse direction as weft threads. A nonwoven fabric can be described as a disordered structure (in particular, in a tangled arrangement) made of filaments or fibers or cut yarns of limited length, which are joined together to form a fiber layer or a fiber nap and are bonded together (in particular by friction). A shaped body can also be created in the shape of a sphere. Shaped bodies can also consist of particles containing cellulose, such as, in particular, beads (i.e.,Cellulose products can be provided in granules or spheres, or flakes, which can be further processed in this form. Possible cellulose products therefore also include particulate structures such as granules, spherical powders, or fibrids. A product is preferably formed by extruding a cellulose-containing spinning solution through an extrusion die, as this method allows for the production of large quantities of cellulose products with a very uniform shape. Another possible cellulose product is a sponge or, more generally, a porous product. According to exemplary embodiments, these products can be used, for example, to manufacture yarns, textiles, gels, or composite materials.

[0011] For the purposes of this application, the term "textile material" may be understood to include, in particular, textile raw materials, textile structures manufactured therefrom, and finished products manufactured therefrom. Textile raw materials may be, in particular, natural fibers and / or synthetic fibers, especially those containing or consisting of cellulose. Textile material may also contain non-textile raw materials that can be processed into linear, planar, and three-dimensional structures using various methods. Therefore, linear textile structures (such as yarns or threads), planar textile structures (such as woven fabrics, braids, nonwovens, and felts), and three-dimensional textile structures (such as textile tubes, stockings, or semi-finished textile products) can be manufactured from these raw materials.Textile materials in the form of products or finished goods can be supplied to a processor or consumer using the aforementioned products.

[0012] Within the scope of this application, the term "mechanical separation" can be understood to mean, in particular, at least one separation procedure in which mixtures with different properties are separated from each other or from a carrier medium. Possible mechanical separation methods for substances from a carrier medium include filtration, sedimentation, and separation in a centrifugal separator. Possible methods for separating substances with different properties include floatation, sieving, separation according to density, or other properties such as magnetism, conductivity, surface area, etc.

[0013] Within the scope of this application, the term "chemical separation" can be understood to mean, in particular, at least one separation procedure that utilizes a chemical separation mechanism in which at least one of the species to be separated can be chemically transformed into another substance during the separation process. Specifically, in chemical separation, one species (for example, non-cellulosic fibers) can be selectively degraded relative to another species (for example, cellulosic fibers). Thus, in chemical separation processes, substances or compounds can be separated using chemical properties and chemical reactions. Examples of chemical separation processes include separation based on different solubilities, separation based on chemical structure, etc.

[0014] Within the scope of this application, the terms "fiber components" or "fiber-related components" may be understood to mean, in particular, components (for example, shredded textile pieces) of the textile material that consist entirely or substantially of fibers or at least have a predominant proportion of fiber material (for example, at least 80% by weight fibers, and in particular at least 90% by weight fibers). The term "fibrous components" accordingly refers to components of the textile material that are characterized by fibers and that contain, at most, a minor proportion of components that do not exhibit fiber characteristics. For example, fibers of textile material may include cellulose fibers, such as lyocell fibers, viscose fibers, and / or cotton fibers. Furthermore, the fibers may also include synthetic fibers, such as polyester and / or elastane.

[0015] For the purposes of this application, the terms "non-fiber components" or "non-fiber-related components" may be understood to mean, in particular, components (for example, shredded textile pieces) of the textile material that do not consist entirely or substantially of fiber material or that at least contain a vast majority of materials other than fiber material (for example, no more than 20% by weight of fibers, and further, in particular, no more than 10% by weight of fibers). Non-fiber components of textile material may, for example, include buttons and zippers.

[0016] According to an exemplary embodiment of the invention, a method for producing molded bodies containing cellulose from recycled textile materials, preferably used clothing and / or textile manufacturing residues, is provided. Although such starting materials are usually available as blended textiles with a high degree of inhomogeneity in their composition and with a high proportion of foreign materials (for example, polyester seams and elastane fibers) and foreign bodies (for example, buttons and zippers), and have therefore not previously been considered for producing high-purity cellulose molded bodies, the described method allows molded bodies to be produced from used clothing, yarn waste, cutting remnants, and the like. In a corresponding process, the textile materials can first be shredded.Larger foreign bodies not present in the form of fibers can then be largely removed. The remaining fiber components can then undergo a mechanical treatment to separate the cellulose fibers from other fibers, followed by a chemical treatment to separate the cellulose fibers from any remaining fibers. The result is relatively pure cellulose components from which chemically regenerated fibers can be produced (for example, using the lyocell or viscose processes). This procedure is simple, environmentally friendly, and can be easily implemented on an industrial scale. In this way, it is efficiently possible to sustainably produce molded objects containing cellulose from recycled textile material.

[0017] Further examples of the method are described below.

[0018] According to one embodiment, the comminution of the textile material can involve shredding. In particular, the textile material can be comminuted (for example, using at least one guillotine) into textile pieces with an average size of, for example, a few centimeters. It has been found that textile material comminuted in this way is very well suited for subsequently separating fiber components from non-fiber components.

[0019] According to one embodiment, separating at least some of the non-fiber components allows foreign materials from a group consisting of buttons, zippers, seams, and textile printing to be separated from the rest of the textile material. A separation criterion could be, for example, the size and / or material of the non-fiber components.

[0020] According to one embodiment, the separation of non-fiber components from the fiber components can be achieved based on differing physical properties, in particular by means of metal deposition and / or gravitational deposition. Metallic components (for example, zippers, rivets, etc.) can be separated, for instance, due to their magnetic properties. Different effects of gravity on different components can also be used for separation.

[0021] According to one embodiment, mechanical separation can be based on density differences between the non-cellulosic and cellulosic fibers. For example, materials of different densities can be separated in a centrifuge due to differing centrifugal forces. After transferring the components into a liquid medium, some may accumulate on the surface due to their different densities, while other components remain suspended or settle at the bottom.

[0022] According to one embodiment, mechanical separation can occur based on differing electrostatic properties between non-cellulosic and cellulosic fibers. Due to these differing electrostatic properties, the different fibers can react differently to an applied electric field.

[0023] This in turn allows cellulosic fibers to be separated from non-cellulosic fibers.

[0024] According to one embodiment, the mechanical separation can involve suspending (i.e., converting into a suspension) the fiber components in a liquid medium, particularly an aqueous medium, and separating the non-cellulosic fibers from the cellulosic fibers due to differing physical properties in the liquid medium (especially differing gravitational, centrifugal, flotation, and / or electrostatic properties). If the different fibers exhibit different behaviors in a liquid medium due to their different compositions, this also allows for the separation of the different fiber components.

[0025] According to one embodiment, the liquid medium can contain at least one additive to enhance its various physical properties, in particular a dispersant and / or a swelling agent. A dispersant can be understood to be, in particular, an additive that enables or stabilizes the dispersion, i.e., the fine distribution of a substance (for example, a fiber) in a continuous medium (for example, a liquid). A swelling agent can be understood to be, in particular, an additive that promotes the swelling of a substance. Swelling can be understood as a process in which a substance (in particular, a liquid) penetrates a solid and causes an increase in the volume of the latter.Adding one or more such additives to the medium can increase the discrepancies in the properties of the various fibers that necessitate their mechanical separation. This increases the efficiency of the separation process.

[0026] According to one embodiment, the chemical separation process can involve the selective dissolution of at least some of the non-cellulosic fibers or at least some of the cellulosic fibers in a solvent, and the separation, in particular filtration, of at least some of the undissolved fiber components. In other words, the various fibers can be introduced into a medium (for example, a liquid, particularly aqueous) in which only certain of these fibers, in particular selective polyester fibers, dissolve to a significant degree, whereas other fibers, in particular cellulose fibers, exhibit no or only weaker solubility. The fibers that do not dissolve, dissolve only minimally, or dissolve less readily (in particular cellulose fibers) can be filtered or centrifuged off and can then be processed separately from the dissolved fibers.

[0027] According to one embodiment, mechanical and / or chemical separation can result in the separation of synthetic fibers as non-cellulosic fibers. Recycled textile materials, particularly used clothing and / or textile waste, frequently contain non-cellulosic fibers of synthetic origin. Examples of such synthetic fibers include polyester, polyamide, and / or elastane. These can be effectively separated from cellulose fibers using the methods described here.

[0028] According to one embodiment, the chemical separation process can involve the introduction of an alkaline solution, particularly using oxidizing agents, and especially alkaline boiling. In particular, the alkaline solution can be used to degrade non-cellulosic fibers, especially synthetic fibers, and further, especially polyester fibers. Polyester, in particular, can thereby be broken down into water-soluble constituents, which can be separated from the cellulose fibers using the wastewater generated in the process.

[0029] According to a preferred embodiment, the alkaline boiling of the pre-processed cellulose-based (in particular cotton-based) textile material from which cellulosic fibers are enriched (i.e., predominantly cellulosic fibers are obtained) can be further processed to produce further purified dissolved pulp as follows: The fibers, in particular the already enriched cellulosic (or predominantly cellulosic) fibers, can be treated with an alkaline solution (for example, potassium hydroxide) in combination with a gaseous oxidizing agent (for example, O₂) in a pressure vessel (preferably at a pH of at least 9), namely: a) at a temperature between 90 °C and 185 °C; b) for an incubation time of 45 minutes to 270 minutes; c) in the presence of a cellulose-stabilizing additive (for example, a magnesium salt, preferably magnesium sulfate; or a chelating compound based on a transition metal, for example, ethylenediaminetetraacetic acid (EDTA)), preferably at a concentration in the range of 0.01 wt% to 5 wt% based on the fibers supplied; d) at an alkali concentration in the range of 1 wt% to 35 wt% based on the fibers supplied; e) at an initial gas pressure in the range of 1 bar to 21 bar (corresponding to approximately 0.1 MPa to approximately 2.1 MPa).

[0030] The resulting dissolved pulp can then be subjected to a washing procedure.

[0031] Partial degradation of the cellulose fibers in a chemical environment can then be advantageously controlled by influencing the chemical environment so that the resulting degree of polymerization of the cellulose lies within a desired range. It is particularly important to note that the DP value (where DP stands for the average degree of polymerization, i.e., the number of monomer units per macromolecule) can be adjusted in the solvent NMMO, preferably used in the production of the molded parts from the recovered cellulose, to achieve good solubility in NMMO. Typical DP values ​​for recyclates are below 2000 mL / g, preferably below 1000 mL / g, and most preferably below 800 mL / g. These values ​​refer to the limiting viscosity (LV, which correlates with the degree of polymerization of the cellulose) in units of mL / g.Through optional but advantageous additional measures such as selection, mixing, boiling, etc., a GVZ value particularly suitable for the lyocell process can be achieved in the range of 200 ml / g to 700 ml / g.

[0032] According to one embodiment, the chemical separation process can involve converting at least some of the non-cellulosic fibers into soluble, particularly water-soluble, substances, dissolving the soluble substances in a solvent, particularly an aqueous solvent, and separating, particularly by filtration, undissolved cellulosic fibers from the dissolved substances. Thus, the various fibers can be introduced into a solvent (for example, an aqueous one) in which only non-cellulosic fibers dissolve to a significant degree. The fibers that do not dissolve, dissolve only minimally, or dissolve only to a limited extent (particularly cellulose fibers) can be filtered or centrifuged off and then processed separately from the dissolved fibers.

[0033] According to one embodiment, the production of the shaped bodies based on the cellulosic fibers can be carried out using the lyocell process or the viscose process.

[0034] Within the scope of this application, the term "lyocell process" can be understood to mean, in particular, a process for producing cellulose using a direct solvent method. The cellulose for the lyocell process can be obtained from a starting material containing this cellulose. In the lyocell process, the starting material can be dissolved in a suitable solvent (in particular, one containing tertiary amine oxides such as N-methylmorpholine N-oxide (NMMO) and / or ionic liquids, i.e., low-melting salts composed of cations and anions). Dissolution can be achieved, in particular, by dehydration and / or without chemical modification. The resulting solution, which can also be referred to as dope or spinning solution, can then be extruded through one or more spinnerets in the lyocell process.Filaments formed in this way can be precipitated during and / or after their free or controlled fall through an air gap in a water-containing bath (especially in a bath with aqueous NMMO solution) and / or humidity present in the air gap.

[0035] Within the scope of this application, the term "viscose process" can be understood to mean, in particular, a process for producing cellulose using a wet spinning method. The cellulose for the viscose process can be obtained from a starting material (especially wood or wood pulp) containing this cellulose. In successive process steps, the starting material in the viscose process can first be treated with a base (for example, sodium hydroxide), resulting in the formation of alkali cellulose. Subsequent reaction of this alkali cellulose with carbon disulfide produces cellulose xanthate. From this, a viscose spinning solution can be generated by further addition of a base (especially sodium hydroxide), which can be extruded through one or more spinnerets. Viscose filaments are formed by coagulation in a spinning bath.

[0036] According to one embodiment of the Lyocell process, the production of the shaped bodies can involve dissolving the cellulosic fibers in a solvent, transferring the dissolved cellulosic fibers into a spinning mass, extruding the spinning mass through spinnerets to form the shaped bodies, and precipitation of the extruded shaped bodies in a spinning bath. Between dissolving and precipitation, a Lyocell spinning solution produced by the dissolving process can be passed through nozzles and spun into shaped bodies.

[0037] According to one embodiment, the dissolution of the cellulosic fibers can be carried out using a direct dissolution process and / or using tertiary amine oxides, in particular N-methylmorpholine N-oxide, as a solvent. In such a direct dissolution process, the cellulose is physically dissolved in the respective solvent. Preferably, tertiary amine oxides are used as the solvent, particularly N-methylmorpholine N-oxide (NMMO).

[0038] According to one embodiment, the dilution of the dissolved cellulosic fibers can be achieved by an aqueous environment (particularly comprising a water bath, and furthermore, in particular, consisting essentially of water or a mixture of water and solvent). In the Lyocell process, the water reduces the concentration of the solvent that dissolved the cellulose to such an extent that the resulting diluted solution falls below the solubility limit of cellulose, causing the cellulose to precipitate. The coagulation medium (i.e., in particular, the water bath) can be essentially pure water or can be mixed with a solvent.

[0039] According to one embodiment, the process can include bleaching the chemically separated cellulosic fibers. This allows for the removal of dyes. Such bleaching can be oxidative (i.e., bleaching in which dyes are attacked by oxidation, for example, using oxygen or a compound with an -OO group, such as hydrogen peroxide), reductive (i.e., bleaching in which dyes are attacked by reduction and / or converted into a soluble form, particularly for removing vat dyes such as indigo), and / or enzymatic (i.e., bleaching in which dyes are attacked by enzymes, for example, using proteases that biologically cleave proteins). Oxidative bleaching may be preferred because it can effectively remove dyes and allows for simple process control.

[0040] According to a preferred embodiment, bleaching can be carried out in three stages (in particular, in one or more stages, for example, with one, two, three, four, five, or more bleaching stages), for example, by performing an acid wash, (in particular, subsequently) an ozone bleach, and (in particular, subsequently) a peroxide bleach. The acid wash can remove metal ions and / or degrade non-alkaline textile chemicals. The ozone bleach can degrade dyes and advantageously adjust the limiting viscosity and thus the degree of polymerization of the cellulose. The peroxide bleach can further refine the adjustment of the degree of polymerization of the cellulose.

[0041] According to one embodiment, the process, after separating at least some of the non-fiber components, can include further comminution of the separated non-fiber components, recovery of fiber residues from the further comminuted non-fiber components, and feeding the recovered fiber residues back to the fiber components and / or for mechanical separation. Cellulose components may still be bound to the non-fiber components. To avoid losing these for particularly efficient recycling, the non-fiber components can therefore be subjected to another comminution process to separate fiber residues from them, which can then be fed back to the previously separated fiber components.

[0042] According to one embodiment, the process can include separating the fiber components (and, if applicable, the recovered fiber remnants or residues) into individual fibers prior to mechanical separation, in particular by tearing and / or grinding. By reducing the components to the size of individual fibers before mechanical and chemical separation, and optionally shortening the individual fibers, the efficiency of the subsequent separation of cellulosic fibers compared to non-cellulosic fibers can be significantly increased.

[0043] According to one embodiment, the process can include post-processing of the precipitated cellulose to obtain the molded body. Such optional post-processing can, for example, involve drying, impregnating, and / or reshaping the obtained cellulose. By applying appropriate post-processing, it is possible to complete the molded body production at the end of the lyocell process in an application-specific manner.

[0044] According to one embodiment, in the process at most (or only exactly) a portion of the non-cellulosic fibers, in particular only exactly a portion of synthetic fibers made of polyester and / or elastane, can be used to manufacture the molded bodies.

[0045] According to one embodiment, a manufactured molded body can contain elastane as a foreign substance, which is also at least partially dissolved during the cellulose dissolution process. Elastane is used in many textiles, especially clothing, and particularly in secondhand clothing, and can be deliberately left in the cellulose-containing molded body as a foreign substance. It has been found that elastane in a recycled cellulose molded body does not negatively affect its product properties and therefore does not need to be laboriously removed from the starting material to the maximum achievable limit when manufacturing a molded body. It is even possible to impart a certain degree of elasticity to a cellulosic molded body by leaving elastane in it. In this way, molded bodies with modified elastic properties can also be produced.

[0046] According to one embodiment, a manufactured molded body can contain polyester as a foreign substance, which can remain at least partially in the processed textile material when it is dissolved, particularly when it precipitates. Polyester is a foreign substance frequently found in post-consumer used clothing. According to one exemplary embodiment, at least some of this polyester can remain in the manufactured cellulose molded body. Visually, such a residue of polyester in the molded body can function similarly to a hot-melt adhesive and mechanically strengthen a woven or nonwoven fabric made of cellulose. By retaining at least some polyester in the cellulose molded body, a particularly mechanically robust cellulose material can be created, which can also be endowed with thermoplastic properties. According to such an embodiment, the polyester thus leads to increased mechanical robustness.Stability of the manufactured molded body.

[0047] According to one embodiment, an inhomogeneous textile material, particularly a blended fabric, can be used. According to a preferred embodiment, the product or preform can be manufactured at least partially using used clothing as a cellulose source. For example, at least 3% by weight, particularly at least 10% by weight, and more specifically at least 30% by weight, and preferably at least 50% by weight, of used clothing can be used as the starting material for the textile material. It is particularly advantageous for the product to be manufactured using recycled textiles that include or consist of garments previously worn by a user.

[0048] According to one embodiment, the textile material can contain or consist of residues from clothing production and / or, in particular, used clothing worn by consumers. Specifically, the starting material can contain or consist of a recyclable cellulose source, in particular being formed wholly or partially from residues from clothing production and / or used clothing. Within the scope of this application, the term "cellulose source" can be understood to mean, in particular, a medium (especially a solid medium) that provides the cellulose material used as a basis for producing a molded body containing cellulose during a corresponding manufacturing process. An example is wood or wood pulp. Thus, starting materials that are not extracted from a natural resource such as wood for the first time, but rather originate from a previously used product, can also be incorporated into the recycling process.In this context, the use of post-consumer used clothing is particularly advantageous, as such used clothing has a large reservoir of recyclable cellulose.

[0049] Within the scope of this application, the term "remnants from clothing production" can be understood to mean, in particular, rejects and / or offcuts of a textile or yarn containing or consisting of cellulose, wherein these remnants arise during a process for manufacturing clothing. In the production of clothing, for example, a textile containing cellulose is produced as a starting material, from which flat pieces (for example, in the form of a T-shirt half) are then cut. The remaining remnants can, according to an exemplary embodiment, be fed back into a process for producing a molded body containing cellulose. Remnants from clothing production can therefore be a starting material containing or consisting of cellulose that can be used to recover cellulose before a consumer has used the remnants as clothing or in some other way.Residues from clothing production can consist in particular of essentially pure cellulose, especially without separate foreign bodies containing non-cellulose (such as buttons, textile printing or seams).

[0050] For the purposes of this application, the term "used clothing" can be understood to mean, in particular, clothing containing cellulose that has already been used (especially worn) by a consumer, with the aim of recovering at least some of its cellulose. Used clothing can therefore be a cellulose-containing raw material that may (but does not necessarily) contain significant amounts of foreign materials and can be used to recover cellulose after a consumer has used the used clothing as clothing or in some other way. Used clothing can, in particular, consist of a mixture of cellulose and one or more foreign materials, especially synthetic plastics (such as polyester and / or elastane), which are frequently used in clothing, and / or separate foreign bodies that do not contain cellulose (such as buttons, printed fabric, or seams).Polyesters are understood to be polymers with ester functional groups (R-[-CO-O-]-R) in their main chain. Polyesters include polycarbonates and polyethylene terephthalate. Elastane is understood to be a stretchable synthetic fiber with high elasticity. An elastane block copolymer can contain a polyurethane mass fraction of at least 85%.

[0051] According to one embodiment, the textile material can be at least partially freed from crosslinking agents that crosslink the fibers of the textile material during the recovery process. This can be achieved, for example, by means of an alkaline and / or acidic pretreatment, depending particularly on the type of crosslinking agent present. Such a crosslinking agent can be problematic because it can reduce the solubility of lyocell cellulose in lyocell solvents. The at least partial removal of the crosslinking agent by means of a pretreatment (for example, by carrying out an alkaline and / or acidic step) with partial or complete dissolution of the unwanted crosslinking can increase the suitability of the obtained cellulose as chemical pulp for the production of regenerated molded bodies.

[0052] According to one embodiment, the textile material for the recycling process can be mixed with another cellulose source. For example, the other cellulose source can comprise at least one material from a group consisting of wood pulp, rag pulp (in particular, pulp from fabric remnants such as linen, rags, etc.), cotton (i.e., cellulose from a cotton plant, see Figure 5 ), cellulose produced using a lyocell process (see Figure 3 ) and cellulose produced using a viscose process (see Figure 4The other cellulose source can be added flexibly, depending on availability. This ensures that the large-scale application of the recycling process is not hampered by any temporary shortages of a particular cellulose source. Instead, it is possible, for example, to compensate for or offset any shortfalls in used clothing cellulose with other cellulose sources. However, producing the raw material solely from used clothing is preferable.

[0053] The molded bodies produced according to the invention can be used, for example, as packaging material, fiber material, textile composites, fiber composites, nonwovens, needle felts, upholstery wadding, woven fabrics, knitted fabrics, as home textiles such as bed linen, as clothing, as filling material, flocking material, hospital textiles such as underpads, diapers or mattresses, as fabric for thermal blankets, shoe insoles, and wound dressings. Exemplary embodiments of the invention can be applied in a wide variety of technical fields as well as in medicine, cosmetics, and wellness. In medicine, for example, materials for wound treatment and wound healing can be composed of a carrier that determines the mechanical properties and a biocompatible coating material that is particularly compatible with the skin and the surface of the wound. Numerous other applications are possible.

[0054] Exemplary embodiments of the present invention are described in detail below with reference to the following figures. Figure 1 Figure 1 shows a flowchart of a process for recycling cellulose-containing textile material to produce molded bodies according to an exemplary embodiment of the invention. Figure 2 shows an apparatus for producing a molded body containing cellulose according to an exemplary embodiment of the invention. Figure 3 shows a cellulose fiber produced using a lyocell process. Figure 4 shows a cellulose fiber produced using a viscose process. Figure 5 shows a natural cellulose fiber from a cotton plant.

[0055] Identical or similar components in different figures are provided with the same reference numerals.

[0056] Before describing exemplary embodiments with reference to the figures, some basic considerations will be summarized on the basis of which exemplary embodiments of the invention have been derived.

[0057] According to an exemplary embodiment of the invention, a process for producing molded bodies containing cellulose by recycling textile materials is described. In particular, process steps for processing textile materials in the form of used textiles or textile waste into chemical pulp are described below. This process advantageously allows the fibrous cellulosic components contained in the textile feedstock to be isolated or recovered, separated from non-cellulosic components, and purified according to the requirements for chemical pulp.

[0058] In the following, a selection of raw materials as textile material is described according to an exemplary embodiment.

[0059] For the production of chemical pulp, recycled textiles or textile waste with a predominant proportion of cellulosic components, such as cotton and / or regenerated cellulose fibers (especially lyocell fibers, viscose fibers, and modal fibers), can be used as particularly advantageous raw materials. These textile materials or raw materials can be selectively obtained from the total volume of recycled textiles and / or other cellulose sources through manual, semi-automated, or fully automated sorting processes.

[0060] Preferably, raw materials containing exclusively cellulosic components can be selected as textile materials. Examples include production waste (for instance, offcuts from garment manufacturing). Ready-to-use textiles, on the other hand, often contain a proportion of non-cellulosic fibers. Polyester-based sewing threads are one example. Therefore, particularly when processing used textiles, material blends should be assumed that can be used as textile materials or starting materials for the described process.

[0061] After selecting the textile materials, a separation of non-fibrous components or non-fiber components from fibrous components or fiber components, and a disintegration of the raw materials or textile materials can take place.

[0062] Used textiles often contain non-fibrous components (especially macroscopic non-fibrous components, i.e., not merely microscopic components like pigment dyes) or non-fiber components such as buttons and / or zippers as the starting material. These can be removed from the fibrous or fiber components of the selected raw materials or textile materials at the beginning of the processing. According to one exemplary embodiment, the textile materials, pre-sorted (e.g., by color, quality, purity, etc.), can first be shredded into textile pieces using one or more guillotines or a cutting mill. The shredded textile pieces can be, for example, in the form of objects ranging in size from approximately 1 cm to several centimeters, with an average diameter in the range of 1 cm to 5 cm.It is then possible to remove textile pieces to which non-fiber components or non-fiber constituents adhere, or which consist of such materials, from the overall stream based on their physical properties (for example, using a metal separator, gravity, or in another way). This removal can be automated (particularly semi-automated or fully automated). To reduce or completely avoid fiber loss, the separated pieces can advantageously be fed into further comminution and separation stages, and the recovered fibrous materials can be reintroduced into the main process for the production of chemical pulp.

[0063] Textile pieces made from purely fibrous materials, i.e., the pure fiber components of the textile material, can subsequently be further processed using mechanical processes (for example, tearing, milling) so that the fabrics, knits, yarns, etc., contained within the fiber components can be separated completely or partially into individual fibers. Optionally, this process can also shorten the fiber length. Separation into individual fibers is particularly advantageous in the case of blended yarns. Here, different fibrous materials are physically bonded together at the yarn level.

[0064] This process can also lead to the exposure of microscopic non-fibrous components or non-fiber components. For example, pigments incorporated into the fibers can be exposed, which can then optionally be separated in further procedures, for example based on their physical properties.

[0065] Next, a mechanical separation of the fibrous components is described according to an exemplary embodiment.

[0066] After the disintegration of textile materials or textile raw materials into individual fibers, cellulosic fibers or fiber materials can be separated from non-cellulosic fibers or fiber materials by mechanical separation processes. For this purpose, the individual fibers can be suspended in a liquid medium, preferably an aqueous medium, and separated from each other based on their physical properties, for example, gravitationally, electrostatically, and / or flotationally. The suspension of the textile fragments, now separated into individual fibers, in water can be carried out in a mixing tank with an agitator. For example, cotton fibers and polyester fibers can then be separated gravitationally based on their density difference. Optionally, but advantageously, additives such as dispersants and / or swelling agents can be added to the liquid medium to increase the separation efficiency of the respective process.For example, a chemical substance can be added to reduce the surface tension of water and suppress the floating of the shredded textile pieces. Mechanical separation can be carried out in multiple stages to improve the separation effect.

[0067] Preferably, gravitational separation can be carried out using one or more hydrocyclones (i.e., a centrifugal separator) and / or in a flotation cell.

[0068] After stirring the suspension, it can, according to one embodiment, be fed into a hydrocyclone where the textile pieces, separated particularly into individual fibers, can be separated in the suspension according to their different densities. Cellulose (especially from cotton) has a higher density than polyethylene terephthalate (PET), which in turn has a higher density than elastane. To improve separation efficiency, several hydrocyclones can be connected in a cascade configuration.

[0069] According to one embodiment, a mechanical separation of the fiber materials, carried out as an alternative or supplement to treatment in at least one hydrocyclone, can also be performed in a flotation cell. In particular, the following procedures can be performed in a flotation cell: a) Generation of gas bubbles within the suspension b) Bringing the gas bubbles into contact with the fiber materials from the suspension c) Attachment or adhesion of the fiber materials to be separated to the gas bubbles d) Allowing the gas / solid combinations to rise to a surface where they can be skimmed off

[0070] Due to their lower density, the lighter PET and elastane particles will preferentially rise to the surface in the flotation cell and can be skimmed off, whereas the heavier cellulose particles will remain in the flotation cell. The described treatment in a flotation cell can be carried out continuously or in batches.

[0071] An alternative or supplementary electrostatic separation of the fiber materials can be carried out dry or in a wet process.

[0072] Despite the preferably multi-stage design, complete separation of the materials cannot always be achieved in purely mechanical separation in the exemplary embodiments of the invention. In one embodiment, the input material stream is separated into a predominantly cellulosic stream (consisting mainly of cellulose fibers) and a predominantly non-cellulosic stream (consisting mainly of non-cellulosic fibers). In the cellulosic stream, which is later processed into chemical pulp, non-cellulosic components can first be further selectively removed in a subsequent chemical separation. By selecting suitable process parameters and the number of process stages, a desired target range of non-cellulosic components can be maintained according to the exemplary embodiments.

[0073] The following describes a chemical processing (in particular boiling) of the cellulosic fiber stream according to an exemplary embodiment of the invention.

[0074] With regard to the production of chemical pulp and, in particular, its further use in the production of cellulosic regenerated molded parts and the associated purity requirements, it is advantageous, according to exemplary embodiments of the invention, to chemically separate the predominantly cellulosic material stream (i.e., the cellulosic fibers with small amounts of other substances) obtained after mechanical separation by means of chemical processes, thereby further removing the remaining non-cellulosic components, ideally quantitatively. According to an exemplary embodiment of the invention, this can be achieved by chemical process steps. The aim of these process steps is the selective or preferential degradation of the non-cellulosic components.

[0075] According to an exemplary embodiment, it is also possible to selectively dissolve a component of the fiber materials and subsequently filter off an undissolved component. In one embodiment, the cellulosic fiber stream, or the predominantly cellulosic fibers, can be subjected to alkaline boiling. In this procedure, for example, polyester can be cleaved into the monomers ethylene glycol and terephthalic acid. These are water-soluble and, according to one embodiment, can be separated from the cellulose fibers using process lye. Cellulose degradation reactions can also occur in parallel with the polyester degradation during this boiling process. By appropriately selecting the process parameters, the cellulose degradation can be controlled, according to one embodiment of the invention, to achieve a specific target degree of polymerization.This is advantageous because the degree of cellulose polymerization (expressed as the limiting viscosity number) is a specification criterion for chemical pulp.

[0076] According to one embodiment, the alkaline cooking process can be advantageously supported by the use of oxidizing agents.

[0077] Preferably, according to one embodiment, certain proportions of textile chemicals intrinsically contained in the starting materials (for example, dyes) can be dissolved or broken down and converted into soluble forms during this cooking process.

[0078] A bleaching procedure can then be performed to remove or deactivate dyes.

[0079] Particularly after boiling, according to one embodiment of the invention, the cellulosic fiber stream (i.e., the fiber stream that predominantly contains cellulosic fibers or pulp) can be further processed in a preferably multi-stage bleaching sequence. The aim of such an advantageous bleaching sequence is to achieve a high degree of whiteness by removing or degrading as completely as possible all remaining dyes or textile chemicals. According to one embodiment, oxidative, reductive, and / or enzymatic bleaching stages can be combined. In a simple embodiment, a purely oxidative bleaching stage is advantageously used.

[0080] According to an exemplary embodiment, an AZP sequence can advantageously be used. The A stage (acidic wash) serves in particular to remove dissolved metal ions and to degrade textile chemicals that are not alkaline-degradable. The Z stage (ozone bleach) serves both as a strongly oxidative stage for the degradation of chromophores / dyes and simultaneously as a further stage for adjusting the limiting viscosity. The final P stage (peroxide bleach) then serves in particular for fine-tuning the degree of polymerization (analogous to the limiting viscosity) and for achieving the desired final whiteness. The described bleaching stages are optional: the number and type of bleaching stages, as well as their specific process conditions, can be adapted to the materials available or the specific application.

[0081] In particular, a closed-loop system for reaction media and process chemicals can be advantageously implemented. With an advantageous implementation of recovery processes, the resource requirements (especially with regard to chemicals, energy, and water) of the entire processing process can be kept low, according to exemplary embodiments of the invention.

[0082] Next, an exemplary embodiment of regenerated molded body production, i.e. the production of cellulosic molded bodies, based on the cellulose separated from the textile material, is described.

[0083] By selecting suitable raw materials or textile materials, appropriate process parameters, and combining and coordinating the described process steps, it is possible to produce chemical pulp from used textiles or textile waste as feedstock or textile materials using the processing process described above. This chemical pulp can be used to produce cellulosic regenerated molded bodies, particularly using the viscose process and / or the lyocell process (especially when based on NMMO solvents).

[0084] The quality of the resulting cellulosic regenerated molded bodies is equivalent to that which can be achieved using conventional wood-based chemical pulps.

[0085] Figure 1shows a flowchart 50 of a process for recycling old clothes as cellulose-containing textile material for the production of molded bodies 102 (see Figure 2 ) made of cellulose according to an exemplary embodiment of the invention.

[0086] The textile material used is an inhomogeneous textile material or mixed fabric in the form of post-consumer used clothing that has been used and disposed of by a consumer (see reference 52).

[0087] First, as shown in reference numeral 56, the textile material is shredded in one or more guillotines and / or by shredding, preferably using cutting blades. This yields shredded textile pieces, for example, in the size range between 0.5 × 0.5 cm² and 10 × 10 cm².

[0088] Subsequently, non-fiber components or textile fragments of the shredded textile material are separated from the fiber components or textile fragments of the shredded textile material. Non-fiber components can include textile fragments with foreign materials such as buttons, zippers, seams, and / or textile printing. More precisely, those textile fragments that have a material or are embossed with a material different from fibers are removed. Preferably, the separation 58 of the non-fiber components from the fiber components can be achieved by a process that separates the non-fiber components based on their different physical properties compared to the fiber components. For example, textile fragments made of or containing metallic rivets or zippers can be separated from the rest of the shredded textile fragments using a metal separator.Plastic buttons can be separated from textile fiber-dominated textile pieces by gravity separation, taking advantage of the different densities of the heterogeneous mixture of textile pieces (for example, by centrifugation, filtration, etc.).

[0089] Optionally, the separated (predominantly non-fiber) components can then undergo further shredding 60. For example, the non-fiber components can be further shredded using a guillotine. This allows residual fiber materials to be separated from the textile pieces dominated by non-fiber components and reintroduced into the recycling process. In other words, fiber residues (in the form of further fiber components) are recovered 62 from the further shredded predominantly non-fiber components. The recovered fiber residues can be added back to the fiber components for further cellulose extraction, see reference 63.

[0090] Subsequently, for example using cutting mills, the fiber components and the optionally recovered fiber residues can be further reduced or separated into individual fibers. The aforementioned components or textile pieces can therefore be shredded into threads, and these threads can then be further reduced to completely separated fibers.

[0091] According to the described embodiment, a mechanical separation 66 then takes place between non-cellulosic fibers (in particular synthetic fibers such as polyester, polyamide, or elastane, which are frequently found in used textiles) and the fiber components (including fiber residues) from cellulosic fibers. The mechanical separation 66 can be carried out in different ways in various embodiments. For example, the mechanical separation 66 can be based on density differences between the non-cellulosic fibers and the cellulosic fibers. Alternatively or additionally, the mechanical separation 66 can be based on different electrostatic properties between the non-cellulosic fibers and the cellulosic fibers.

[0092] In the Figure 1In the illustrated embodiment, the mechanical separation 66 involves suspending 68 the fiber components in an aqueous medium. In other words, the fiber components are placed in a liquid container. Subsequently, the non-cellulosic fibers are separated 70 from the cellulosic fibers in the aqueous medium due to the different flotation properties of the two constituents. Flotation is a physicochemical separation process for fine-grained solids based on the different surface wettability of the particles. Advantageously, a dispersant and / or a swelling agent can be added to the aqueous medium in which the flotation separation is carried out, which enhances the different physical properties of non-cellulosic fibers compared to cellulosic fibers that are exploited during the separation.

[0093] Following this mechanical separation 66, it is advantageous to chemically separate 76 another portion of the non-cellulosic (especially synthetic) fibers from the cellulosic fibers in order to further increase the cellulose content of the extract. There are also various possibilities for the chemical separation 76.

[0094] In the described embodiment, the chemical separation 76 can involve the selective dissolution 72 of only the cellulosic fibers in a solvent (for example, NMMO). In other words, the solvent can be selected such that only the cellulosic fibers, and not non-cellulosic (PET) fibers, are dissolved to any significant extent. This allows for subsequent filtration of the non-cellulosic (PET) fibers that do not dissolve, see reference numeral 74.

[0095] In a particularly preferred embodiment, the chemical separation 76 after the mechanical separation 66 (with or without the intermediate procedure according to reference numerals 72 and 74) comprises alkaline boiling using an alkaline solution with oxidizing agents (see reference numeral 78).

[0096] During chemical separation 76, non-cellulosic fibers can be converted 80 into water-soluble substances. For example, polyester can be converted into water-soluble monomers by alkaline boiling. The water-soluble substances can then be dissolved 82 in an aqueous solvent. Subsequently, undissolved cellulosic fibers can be filtered off from the dissolved substances (see reference numeral 84).

[0097] After chemical separation 76, the process can be continued with bleaching 86 of the chemically separated cellulosic fibers to remove or deactivate dyes or the like. For example, the bleaching 86 can be oxidative bleaching. According to a preferred embodiment of the invention, the bleaching 86 can comprise carrying out 88 an acid wash, followed by carrying out 90 an ozone bleach, and in turn followed by carrying out 92 a peroxide bleach. By bleaching 86, dyes and other chemical residues can be removed from the recycled textile materials.

[0098] From the cellulosic material obtained therefrom, cellulosic molded bodies 102 in the form of nonwovens are then produced using the lyocell process (or alternatively using the viscose process) (see reference numeral 94).

[0099] For this purpose, a direct dissolution 96 of the cellulosic material obtained after bleaching 86 in a solvent 116 (compare Figure 2For example, the removal of tertiary amine oxides such as N-methylmorpholine N-oxide (NMMO) is advantageously possible without further chemical pretreatment. More precisely, the material can be directly dissolved, forming a spinning mass. In this way, the manufacturing and recycling process can be carried out exceptionally easily, quickly, and in an environmentally friendly manner. Surprisingly, it has been found that small amounts of foreign substances (such as polyester or elastane) remaining in the recovered cellulosic material after the described procedure do not interfere with the lyocell process or negatively affect the quality of the recovered lyocell cellulose. On the contrary, certain amounts of elastane can remain in the produced cellulose fibers without impairing their properties.For example, elastane may be present in a molded part as a foreign substance at a minimum of 0.001% by weight, in particular at least 0.01% by weight, and further, in particular at least 1% by weight, based on the total weight of the molded part. Certain amounts of remaining polyester do not impair the product obtained; on the contrary, they can even strengthen the mechanical integrity of the molded part 102 to be manufactured. For example, polyester may be present in a molded part as a foreign substance at a minimum of 0.001% by weight, in particular at least 0.01% by weight, and further, in particular at least 1% by weight, based on the total weight of the molded part.

[0100] After dissolving the aforementioned material in solvent (preferably NMMO), the resulting lyocell spinning solution can be pressed through one or more spinnerets, producing threads or filaments of honey-like viscosity (see block 97, which concerns this spinning or extrusion).

[0101] During and / or after the settling of these threads or filaments, they are brought into contact with an aqueous environment and thereby diluted. The concentration of the solvent 116 in the threads or filaments is reduced in atmospheric humidity or an aqueous liquid bath to such an extent that the lyocell spinning solution is converted into a solid phase of cellulose filaments. In other words, the cellulose filaments precipitate, settle, or coagulate (see reference 98). This results in a preform of the shaped body 102. The spinning mass is then extruded 97 into shaped bodies 102 by means of precipitation 98 in a spinning bath (see reference 191). Figure 2 ).

[0102] Furthermore, the process can include post-processing 99 of the precipitated shaped bodies 102. Such post-processing 99 can, for example, include drying, impregnating, and / or reshaping the resulting shaped bodies 102. For example, the shaped body 102 can be processed by the described manufacturing process into fibers, a film, a fabric, a nonwoven, a sphere, a porous sponge, or beads and then put to further use. The procedures corresponding to the production 94 of the shaped bodies 102 can be carried out by means of the in Figure 2 The apparatus 100 shown is used for this purpose. The starting material 110 is the cellulose-containing material obtained after bleaching 86.

[0103] Figure 2Figure 1 shows an apparatus 100 according to an exemplary embodiment of the invention for producing a molded body 102 containing cellulose, which can be produced, for example, in the form of a nonwoven fabric, as a fiber, film, sphere, textile fabric, sponge, or in the form of beads or flakes. Figure 2The formed body 102 is produced directly from a spinning solution 104. The latter is converted into cellulose fibers 108 as a formed body 102 by means of a coagulation fluid 106 (in particular, atmospheric moisture) and / or a coagulation bath 191 (for example, a water bath that optionally contains tertiary amine oxides such as N-methylmorpholine N-oxide (NMMO)). A lyocell process can be carried out using the apparatus 100. In this way, essentially endless filaments or fibers 108, or mixtures of essentially endless filaments and fibers 108 of discrete length, can be produced as formed bodies 102. A plurality of nozzles, each having one or more openings 126 (which can also be referred to as spinning holes), are provided to expel lyocell spinning solution 104.

[0104] How Figure 2A cellulose-based starting material 110 can be supplied to a storage tank 114 via a dosing device 113.

[0105] According to one embodiment, water can be introduced into the cellulose-based starting material 110 by means of a solvent 116 (in particular NMMO) described in more detail below. The cellulose-based starting material 110 itself can also already contain a certain residual moisture content (dry pulp, for example, often has a residual moisture content of 5% to 8% by weight). In particular, according to the described embodiment, the starting material 110 can be added directly to a mixture of water and solvent 116 without pre-moistening. Figure 2 The optional water tank 112 shown can then be omitted.

[0106] According to an alternative embodiment, the cellulose-containing starting material 110 can be additionally moistened to provide moist cellulose. For this purpose, water from an optional water reservoir 112 can be supplied to the storage tank 114 via the metering device 113. Therefore, the metering device 113, controlled by a control unit 140, can supply adjustable relative quantities of water and starting material 110 to the storage tank 114.

[0107] A suitable solvent 116, preferably tertiary amine oxides such as N-methylmorpholine N-oxide (NMMO), or an aqueous mixture of solvent 116, for example a 76% solution of NMMO in water, is contained in a solvent container. The concentration of solvent 116 can be adjusted in a concentrating unit 118 either by adding pure solvent or water. The solvent 116 can then be mixed with the starting material 110 in definable relative amounts in a mixing unit 119. The mixing unit 119 can also be controlled by the control unit 140. This dissolves the cellulose-containing starting material 110 in the concentrated solvent 116 in a dissolving unit 120 in adjustable relative amounts, thereby yielding the lyocell spinning solution 104.The relative concentration ranges (also known as spinning windows) of the components starting material 110, water and solvent 116 in the spinning solution 104 for the production of cellulosic regenerated molded bodies according to the Lyocell process can be suitably adjusted, as is known to a person skilled in the art.

[0108] The lyocell spinning solution 104 is fed to a fiber production device 124 (which may be equipped with a number of spinning beams or jets 122).

[0109] When the lyocell spinning solution 104 is guided through the openings 126 of the jets 122, it is divided into a plurality of parallel filaments of lyocell spinning solution 104. The described process transforms the lyocell spinning solution 104 into increasingly long and thin filaments, the properties of which can be adjusted by appropriately setting the process conditions, controlled by the control unit 140. Optionally, a gas flow can accelerate the lyocell spinning solution 104 on its way from the openings 126 to a fiber receiving unit 132.

[0110] After the lyocell spinning solution 104 has moved through the jets 122 and further downwards, the long and thin threads of the lyocell spinning solution 104 interact with the coagulation fluid 106.

[0111] During the interaction with the coagulation fluid 106 (for example, water), the solvent concentration of the lyocell spinning solution 104 is reduced, so that the cellulose of the starting material 110 is at least partially coagulated or precipitated as long and thin cellulose fibers 108 (which may still contain residues of solvent and water).

[0112] During or after the initial formation of the individual cellulose fibers 108 from the extruded lyocell spinning solution 104, the cellulose fibers 108 are taken up by the fiber uptake unit 132. The cellulose fibers 108 can be inserted into the Figure 2The cellulose is immersed in the coagulation bath 191 (for example, a water bath, optionally containing a solvent such as NMMO) and can complete its precipitation upon interaction with the liquid of the coagulation bath 191. Depending on the process setting of the coagulation, the cellulose can form cellulose fibers 108 (as shown, whereby the cellulose fibers 108 can be monolithic or integrally fused together ("merging") or can exist as separate cellulose fibers 108) or a film of cellulose can form on the fiber uptake unit 132 (not shown in the diagram). Figure 2 (shown).

[0113] The cellulose fibers 108 are extruded from the spinnerets of the jets 122 and passed through the spinning bath or coagulation bath 191 (containing, for example, water and NMMO in low concentration for precipitation / coagulation). During this process, the cellulose fibers 108 are guided around a deflecting roller 193 within the coagulation bath 191 and, outside the coagulation bath 191, are fed to a take-up galette 195. The take-up galette 195 ensures further transport and stretching of the cellulose fibers 108 to achieve a desired titer. After the take-up galette 195, the fiber bundle of cellulose fibers 108 is washed in a washing unit 180, optionally aerated, and finally cut (not shown).

[0114] Although this in Figure 2Not shown, solvent 116 of the lyocell spinning solution 104, which has been removed from the cellulose fibers 108 during coagulation and subsequent washing in the washing unit 180, can be at least partially recovered or recycled and transferred back into the storage tank 114 in a subsequent cycle.

[0115] During transport along the fiber pickup unit 132, the molded body 102 (here in the form of cellulose fibers 108) can be washed by the washing unit 180, which supplies a washing liquid to remove solvent residues. Afterwards, the molded body 102 can be dried.

[0116] The molded body 102 can also be subjected to post-treatment, see the schematically illustrated post-treatment unit 134. For example, such post-treatment can include hydro-tanglement, needle treatment, impregnation, steam treatment with pressurized steam and / or calendering, etc.

[0117] The fiber receiving unit 132 can feed the shaped body 102 to a winding device 136, where the shaped body 102 can be wound up. The shaped body 102 can then be fed as rolled material to an entity that manufactures products such as wipes or textiles based on the shaped body 102.

[0118] Figure 3Figure 200 shows a cross-section of a cellulose fiber 200 produced using a lyocell process. The cellulose fiber 200 produced using a lyocell process has a smooth, round outer surface 202 and is homogeneously filled with cellulose material, free of macroscopic holes. It can therefore be clearly distinguished by a person skilled in the art from cellulose fibers produced using a viscose process (see reference numeral 204 in Figure 200). Figure 4 ) and cellulose fibers from cotton plants (see reference 206 in Figure 5 ) can be distinguished.

[0119] Figure 4 Figure 1 shows a cross-section of a cellulose fiber 204 produced using a viscose process. The cellulose fiber 204 is cloud-shaped and exhibits a plurality of arc-shaped structures 208 along its outer circumference.

[0120] Figure 5Figure 206 shows a cross-section of a natural cellulose fiber 206 from a cotton plant. The cellulose fiber 206 is kidney-shaped and has a material-free lumen 210 as a fully enclosed cavity inside.

[0121] Based on the significant geometric or structural differences of the fibers according to Figures 3 to 5 Is it possible for a specialist to determine, for example under a microscope, unambiguously whether a cellulose fiber was formed using the lyocell process, the viscose process or naturally in a cotton plant?

[0122] It should also be noted that "having" does not exclude any other elements or steps, and "a" or "an" does not exclude a plurality. Furthermore, it should be noted that features or steps described with reference to one of the above embodiments may also be used in combination with other features or steps of other embodiments described above. Reference numerals in the claims are not to be considered as limitations.

Claims

1. Method of recycling a cellulose-comprising textile material for manufacturing regenerated cellulosic molded bodies (102), wherein the method comprises: comminuting (56) the textile material; separating (58) at least a part of non-fiber constituents of the comminuted textile material from fiber constituents of the comminuted textile material; mechanically separating (66) at least a part of non-cellulosic fibers of the fiber constituents from cellulosic fibers of the fiber constituents, and subsequently chemically separating (76) at least one further part of the non-cellulosic fibers from the cellulosic fibers; generating (94) the molded bodies (102) based on the cellulosic fibers after mechanically separating (66) and chemically separating (76).

2. Method according to claim 1, comprising at least one of the following features: wherein comminuting (56) the textile material comprises shredding; wherein, during separating (58) at least a part of non-fiber constituents, foreign matters from a group which consists of buttons, zip fasteners, seams, and textile print, are separated from a rest of the textile material; wherein separating (58) the non-fiber constituents from the fiber constituents is performed due to different physical properties, in particular by metal separation and / or gravitational separation; wherein mechanically separating (66) is performed based on density differences between the non-cellulosic fibers and the cellulosic fibers; wherein mechanically separating (66) is performed based on different electrostatic properties between the non-cellulosic fibers and the cellulosic fibers.

3. Method according to claim 1 or 2, wherein mechanically separating (66) comprises: suspending (68) the fiber constituents in a liquid medium, in particular an aqueous medium; separating (70) the non-cellulosic fibers from the cellulosic fibers due to different physical properties in the liquid medium, in particular different gravitational, centrifugal force-related, flotational and / or electrostatic properties.

4. Method according to claim 3, wherein the liquid medium comprises at least one additive for enhancing the different physical properties of non-cellulosic fibers and of cellulosic fibers, in particular a dispersing agent and / or a swelling agent.

5. Method according to one of the claims 1 to 4, wherein chemically separating (76) comprises: selectively solving (72) only at least a part of the non-cellulosic fibers or only at least a part of the cellulosic fibers in a solvent; separating (74), in particular filtering, at least a part of the non-solved fiber constituents.

6. Method according to one of the claims 1 to 5, wherein chemically separating (76) comprises supplying an alkaline solution, in particular using oxidizing agents, in particular an alkaline boiling.

7. Method according to claim 6, wherein supplying the alkaline solution is performed for degrading non-cellulosic fibers, in particular synthetic fibers, further in particular polyester fibers.

8. Method according to one of the claims 1 to 7, comprising at least one of the following features: wherein chemically separating (76) comprises: converting (80) at least a part of the non-cellulosic fibers to soluble, in particular water-soluble, substances, solving (82) the soluble substances in a solvent, in particular an aqueous solvent, and separating (84), in particular filtering, non-solved cellulosic fibers from the solved substances; wherein mechanically separating (66) and / or chemically separating (76) comprises separating synthetic fibers as non-cellulosic fibers; wherein generating (94) the molded bodies (102) is performed based on the cellulosic fibers by the lyocell-method or by the viscose-method.

9. Method according to one of the claims 1 to 8, wherein generating (94) the molded bodies comprises: solving (96) the cellulosic fibers in a solvent (116) and transferring the solved cellulosic fibers in a spinning mass; extruding (97) the spinning mass through spinning nozzles and subsequently precipitating (98) in a spinning bath (191).

10. Method according to claim 9, comprising at least one of the following features: wherein solving (96) the cellulosic fibers is performed by a direct solving method and / or by tertiary amine oxides, in particular N-methylmorpholine-N-oxide, as solvent; wherein precipitating (98) in a spinning bath (191) is caused by an aqueous milieu, in particular comprising an air humidity and / or a water bath, further in particular substantially consisting of water or a mixture of water and solvent (116).

11. Method according to one of the claims 1 to 10, wherein the method comprises bleaching (86) the chemically separated cellulosic fibers.

12. Method according to claim 11, wherein bleaching (86) comprises at least one of a group which consists of oxidative bleaching, reductive bleaching, and enzymatic bleaching.

13. Method according to claim 11 or 12, wherein bleaching (86) comprises: performing (88) an acidic wash; in particular subsequently, performing (90) ozone bleaching; and in particular subsequently, performing (92) peroxide bleaching.

14. Method according to one of the claims 1 to 13, wherein the method, after separating (58) at least a part of the non-fiber constituents, comprises: further comminuting (60) the separated non-fiber constituents; recovering (62) fiber residues from the further comminuted non-fiber constituents; and supplying (63) the recovered fiber residues to the fiber constituents and / or to mechanically separating (66).

15. Method according to one of the claims 1 to 14, comprising at least one of the following features: wherein the method, prior to mechanically separating (66), comprises separating (64) the fiber constituents to single fibers, in particular by ripping and / or milling; wherein the method comprises post-processing (99) the precipitated molded bodies (102); wherein in the method at most a part of the non-cellulosic fibers, in particular at most a part of polyester and / or at most a part of elastane, from the textile material is co-used for manufacturing the molded bodies (102); wherein a non-homogenous textile material, in particular a textile mixed tissue, is used as textile material; wherein the textile material comprises or consists of residues from a clothing manufacture and / or used clothes which are worn by a user; wherein a molded body (102) is a fiber, a foil, a sponge, a sphere, or a bead; wherein the method comprises further processing the molded bodies (102) to a product, in particular to a textile planar structure.