Electrostatic separation device for elastic monofilament and cotton short fiber yarn in velvet

Abstract

The invention relates to a device and a method for extracting synthetic fiber material (7a) from mixed textile waste fiber material (7a, 7b) comprising synthetic fiber material (7a) and natural fiber material (7b). The extraction module (2) of the present invention comprises: an electrostatic charging unit (21) configured to be mountable at a fabric recycling machine (1) for charging a fiber pile (7) of a mixed fabric fiber material and / or for moving an electrically charged synthetic fiber material closer to the surface of the pile (7); and a separation stage (22) comprising separation means (221, 222, 223) for removing a layer, in particular a surface layer, of the pile (7) comprising an increased or reduced concentration of synthetic fiber material (7a). A method for retrofitting a fabric recycling machine (1) with such an extraction module (2) is also disclosed.

Description

Technical Field

[0001] The field of the invention is a recycling machine and a recycling method for recycling textile materials containing mixed yarn waste, in particular for recycling cotton fibers. The invention broadly relates to an apparatus and a method for recycling textile materials containing natural fibers mixed with elastic synthetic monofilament fibers, wherein the elastic monofilament fibers should be extracted to recover the natural fibers. More specifically, the invention comprises an extraction module and an extraction method for extracting elastic synthetic monofilament materials from the fleece of mixed textile waste fiber materials, and further comprises a textile recycling machine or a fine opening stage thereof comprising such an extraction module, a textile recycling method comprising such an extraction method, and a method for retrofitting a textile recycling machine with such an extraction module. Background Art

[0002] WO2021 / 115931A1 published on June 17, 2021 in the name of Lenzing AG discloses a process for recovering starting materials from mixed textile waste containing blended fabrics. The treatment of mixed textile waste containing cellulose and polyester components includes the following steps: water treatment to depolymerize and dissolve the polyester component; separation of the cellulose component from the treatment solution to recover the cellulose raw material; filtering the treatment solution; and precipitation and recovery of the polyester raw material including terephthalic acid using an adsorption filter medium. However, the cellulosic material recovered by such chemical treatments typically contains impurities, which makes it unsuitable for fiber spinning.

[0003] EP 1 234 900 A1 published on August 28, 2002 in the name of Maschinenfabrik Rieter AG discloses a cleaning method and a device for removing particulate impurities, such as plastic particles or other particles, from raw cotton fiber material.

[0004] US3308944A published on March 14, 1967 in the name of Reclamation Trades Res Organis discloses a separation of a mixture of textile fibers by electrostatic means. The separation process involves dispersing the fibers in an air stream and electrostatically charging them. The wool fibers in the dispersion may acquire a positive charge and the polyester fibers may acquire a negative charge, both of which are of sufficient magnitude to achieve separation purposes. The different decay rates of similar charges on different fibers in the air stream may also be used to separate the fibers.

[0005] CN107956081A, published on April 24, 2018 in the name of Ningbo High-tech Zone Shengwentu Textile Co., Ltd., discloses a fabric device for generating silk, thread, etc. The fabric device includes a fabric flattening line with a conveyor belt and a flattening roller for flattening loose fabric materials. The improvement is that the flattening roller is replaced by an electrostatic roller, which is part of the waste yarn absorption and melting extraction mechanism. Static electricity is generated in the electrostatic roller by the friction between the inner plastic roller and the outer rubber roller, so that the polyester waste fiber is charged, adheres to the outer roller, is scraped off from the outer roller by a scraper and collected in a waste collection box. The polyester waste is sucked into the melting box by the airflow, melted and flows to the extraction table with extraction holes, sucked by the inclined piston plate through the extraction holes and slides into the lateral drafting box under the action of gravity. The up and down movement of the piston plate also provides airflow to the conveyor belt through the first and second air supply channels, which blows the loose fabric on the conveyor belt and makes the polyester waste yarn stand upright on the surface of the fabric, thereby making it easier for the outer roller to absorb the polyester waste yarn. The device incorporates a polyester fusing mechanism and is therefore relatively complex. The device is particularly suitable for extracting polyester waste yarn from loose fiber fabrics.

[0006] CN109881306A discloses a method for separating and recycling blended fabrics. The method comprises the following steps: (1) color measurement; (2) fiberization treatment, wherein polyester and cotton blended fabrics are fiberized by mechanical hook weaving, and the classified polyester and cotton blended fabrics are disassembled into uniformly dispersed polyester and cotton blended fibers; (3) chemical pretreatment, which is used to improve the dispersibility and conductivity of the polyester and cotton blended fibers and increase the conductivity difference between the polyester and cotton fibers; (4) dispersion, wherein the mixed fibers are dispersed into a uniform thin layer by mechanical vibration or air flow sedimentation; (5) electrostatic adsorption and separation, wherein the multi-component mixed fibers obtained after pretreatment and dispersion are placed in an electric field, and under the action of the electric field force, the component fibers undergo separation of fast and slow flying upwards or separation of far and near falling deviations; and (6) recovery and reuse treatment of the separated polyester and cotton fibers.

[0007] In general, currently known methods rely on chemical methods in aqueous solution, or electrostatic methods in air flow, to separate synthetic polyester fibers from natural cotton fibers in blended fabrics containing synthetic fibers (such as polyester) in a typical range of, for example, several tens of percent, or, for example, in a range of 15% to 85% or a sub-range thereof. Summary of the invention

[0008] The object of the invention is to provide a device and a method for improved and simplified removal of synthetic fiber materials from fiber fleece containing mixed yarn waste. This object is achieved by the subject matter set forth in the independent claims. Some embodiments are given in the dependent claims and claim combinations and provide further developments.

[0009] Throughout this application, natural fiber materials are or include cellulosic fiber materials, such as, for example, cotton fibers, hemp fibers, flax fibers, ramie fibers, sisal fibers, bamboo fibers, or mixtures thereof. Cellulose fibers have important advantages, such as low density, low cost, they are recyclable and biodegradable.

[0010] Fabrics typically contain a mixture of natural and synthetic fibers. For example, a fabric may contain or be made from a core yarn having synthetic continuous filaments that form a stretchable core and natural fiber rovings that provide bulk to the core. This is in contrast to blended fabrics, which contain significant amounts of both synthetic and natural fiber materials.

[0011] Examples of synthetic fiber materials are polyester fibers, polyurethane fibers, spandex fibers, polyamide fibers, viscose fibers or rayon fibers, acrylic fibers, nylon fibers. When recycling such textile materials, mixed yarn waste containing natural and synthetic fiber materials is obtained. There is a need to extract synthetic fiber materials in order to regain natural fibers.

[0012] The core yarn fabric waste material comprises a relatively small amount of synthetic fiber material, for example in the range of 1% to 15%, preferably 1% to 10%, more preferably 2% to 5% (for example in jeans). However, the core yarn fabric waste material may also include up to 20% or up to 30% synthetic fiber material, for example in swimwear or the like.

[0013] The preferred synthetic fiber material for core yarn fabric is spandex, which provides stretchability in combination with cotton or viscose fibers, which provides durability to the fabric material. When recycling such core yarn fabric waste materials, a relatively small amount of synthetic fibers must be efficiently extracted in order to obtain a high purity of separated natural and synthetic fiber materials.

[0014] Throughout this application, the term "fiber flock" or simply "fleece" describes a collection of textile fibers bonded together in a nonwoven manner. Such flocks can form a coherent stream of fibrous material that can be transported by a conveyor belt, drive rollers, or other mechanical transport device. Such flocks are distinguished from a fiber stream that can be pneumatically transported by an air flow.

[0015] The present invention relates to an extraction module for extracting synthetic fiber material from mixed textile waste fiber material comprising synthetic fiber material and natural fiber material, in particular including or being core yarn waste fiber material, in particular for implementing the extraction method disclosed herein, the extraction module comprising:

[0016] a. an electrostatic charging unit configured to be mounted at a fabric recycling machine for charging the fiber pile of a mixed textile fiber material and / or for moving the charged synthetic fiber material closer to the surface of the pile, and

[0017] b. A separation stage comprising separation means for removing layers of the fibre fleece containing increased or decreased concentrations of synthetic fibre material, in particular surface layers.

[0018] The extraction module has the advantage that natural fiber material can be recovered from the fleece of mixed yarn waste material with improved quality. This is achieved by using a two-step process implemented in an electrostatic charging unit or submodule and a separation stage or preferably a separation unit or submodule. The extraction module allows to extract synthetic fiber material from the fleece of mixed yarn waste material with high efficiency and relatively low cost. Preferably, the extraction module is configured to be installed in a textile recycling machine, in particular as a retrofit module.

[0019] In an embodiment, the electrostatic charging unit or submodule is configured to be installed, in particular retrofitted, at a fine opening stage of a fabric recycling machine. In particular, the electrostatic charging unit may be installed or retrofitted after a carding stage of a fabric recycling machine.

[0020] In an embodiment, the extraction module may include an electrical interface for providing electrical power to the electrostatic charging unit. Alternatively or in addition, the electrostatic charging unit may include a device for friction-induced electrostatic charging of the fiber fleece, such as an electrostatic roller that provides a triboelectric effect between two members of different materials, such as a first plastic roller and a second roller of different material or a plastic roller and the fleece itself. In additional embodiments, the extraction module may include a mounting device configured for mounting or retrofitting the electrostatic charging unit to the fabric recycling machine.

[0021] In an embodiment, the electrical separation device comprises an electrical separation device for applying an electrical separation field to the charged fiber fleece for moving or further moving the charged synthetic fiber material closer to the surface of the fleece. In particular, the electrical separation device may comprise an electrode for applying the electrical separation field to the charged fiber fleece, and / or may comprise an electric roller or an electrostatic conveyor belt for charging and / or electrically attracting the synthetic fiber material.

[0022] In an embodiment, the separation device comprises a mechanical fiber treatment device for treating the charged fiber pile so as to move the charged synthetic fiber material further closer to the surface of the pile, especially when exposed to the electric separation field. In particular, the mechanical fiber treatment device may comprise a combing roller for combing the charged fiber pile.

[0023] In an embodiment, the separation device comprises a mechanical separation device configured to remove a surface layer comprising an increased concentration of synthetic fiber material. Alternatively or in addition, the separation device comprises a mechanical separation device configured to remove a layer of natural fiber material comprising a reduced concentration of synthetic fiber material, in particular an opposing surface layer or bulk layer. In particular, the mechanical separation device may comprise at least one separation tool selected from the group consisting of: a T-roller, a knife, a scraping tool, a knock-off tool, a brush, a brush roll, a grid, or a combination thereof.

[0024] In an embodiment, the separation stage is a separation unit or submodule configured to be mounted in particular as a retrofit to a fabric recovery machine. In particular, the separation unit may comprise an electrical interface for providing power for driving the separation means and / or further comprise mounting means configured for mounting or retrofitting the mechanical separation unit to the fabric recovery machine.

[0025] In an alternative or additional embodiment, the separation stage is or comprises a modified part of a recycling machine, in particular a fine opening stage or a carding stage of a textile recycling machine. In particular, the modified part of the textile recycling machine may include one or more of the following: a roller modified with an electric or triboelectric device to obtain a chargeable roller; an electric roller modified to be installed near the fiber pile path in the recycling machine; an electric separation field generating device, which for example comprises or is a fixed electrode or an electrostatic conveyor belt modified to be installed near the fiber pile path in the recycling machine; and combinations thereof.

[0026] In an embodiment, the electric separation field generating means comprises an electrostatic conveyor belt which is movable by a drive and comprises a charged pick-up area for attracting charged synthetic fibre material and a release area for discarding the synthetic fibre material, in particular by a brush cleaner or a suction cleaner.

[0027] In an embodiment, the electrostatic conveyor belt is arranged above the mechanical fiber handling device and / or above the mechanical separating device.

[0028] In an embodiment, the mechanical fiber treatment device comprises a combing roller, which rotates in the conveying direction of the fiber pile, for combing the fiber pile and moving it into the electrostatic separation field of the electrical separation device, in particular the electrostatic conveyor belt. This has the following advantages: the fiber pile is looser and subjected to the electrostatic separation field, so that the charged synthetic fiber material can move to the surface layer of the pile adjacent to the electrical separation device (in particular the electrostatic conveyor belt).

[0029] In an embodiment, the mechanical separation device comprises counter-rotating rollers, in particular brush rollers, for separating a first layer of the fiber fleece comprising natural fiber material with a reduced concentration of synthetic fiber material, in particular a bulk layer, from a second layer, in particular a surface layer or an upper surface layer, comprising an increased concentration of synthetic fiber material, in particular when the second layer is adhered to an electrical separation device, and preferably to an electrostatic conveyor belt.

[0030] In other words, the mechanical separation device, in particular a brush roller, can cooperate with the electrical separation device, in particular an electrostatic conveyor belt, so that the first layer is deflected away from the electrical separation device, in particular the electrostatic conveyor belt (for example by moving downward), and the second layer is adhesively attached to the electrostatic conveyor belt and is thereby removed from the fiber fluff.

[0031] In another aspect, the present invention relates to a fabric recycling machine for processing waste yarn containing synthetic fiber materials and natural fiber materials, in particular in the fine opening stage or carding stage of a fabric recycling machine, in particular for implementing the method for recycling fabric as disclosed herein, wherein the fabric recycling machine comprises or is retrofitted with an extraction module as disclosed herein. In particular, the fabric recycling machine comprises or is retrofitted with two or more extraction modules as disclosed herein. Preferably, synthetic fiber materials are removed from the waste yarn to obtain recycled natural fibers of sufficient quality to be reused in fiber spinning or other processes (such as weaving, dyeing and finishing), in particular in fiber rotor spinning.

[0032] In an embodiment of the fabric recycling machine, the electric separation field generating means, in particular the electrostatic conveyor belt, may be mounted on top of a combing device of the fabric recycling machine and / or may replace the cover of the combing device. In a further embodiment, the combing device of the fabric recycling machine may comprise a mechanical fiber handling means and a mechanical separation means.

[0033] In an embodiment, the fabric recovery machine may comprise velvet transporting means for transporting velvet to and from the extraction modules, in particular a feed conveyor belt, an outlet conveyor belt and optionally a back conveyor belt for re-feeding the velvet to at least one of the extraction modules.

[0034] In an embodiment, the fabric recycling machine may comprise a suction roll which is arranged after the separation stage of the extraction module and which serves to re-agglomerate the fiber fleece comprising natural fiber material obtained from the extraction module with increased purity.

[0035] In an embodiment of the textile recycling machine, the extraction module does not comprise pneumatic means for conveying the fluff of the mixed textile waste fiber material and / or the extraction module does not comprise chemical means for extracting components of the fiber material.

[0036] In another aspect, the present invention relates to a method for extracting synthetic fiber material from the fleece of a mixed textile waste fiber material comprising synthetic fiber material and natural fiber material, in particular a method implemented in an extraction module as disclosed herein or in a textile recycling machine as disclosed herein, the method comprising the following method steps:

[0037] a. exposing the velvet to an electrostatic charging field provided by an electrostatic unit for electrostatically charging the synthetic fiber material in the velvet,

[0038] b. applying an electrostatic separation field provided by an electric field generating device for moving the charged synthetic fiber material toward the surface layer of the fleece,

[0039] c. mechanically treating the fleece by means of a mechanical fibre treatment device for promoting the migration of charged synthetic fibre material towards the surface layer of the fleece, in particular when the fleece is exposed to an electrostatic separation field, and

[0040] d. Removal of the layer containing the synthetic fiber material of increased or decreased concentration by separation means, in particular mechanical separation means.

[0041] In an embodiment, the method comprises in step d: removing a surface layer comprising an increased concentration of synthetic fiber material by an electrical separation device and / or removing an opposing surface layer or bulk layer of natural fiber material comprising a decreased concentration of synthetic fiber material by a mechanical separation device.

[0042] In an embodiment, the method may comprise at least one of the following method steps:

[0043] a0. Combing the fiber fleece before step a,

[0044] b0 after step a and before step b the fiber fleece is combed, and

[0045] c0. Combing the fiber pile after step b and before step c.

[0046] In an embodiment, step d may comprise subjecting the fibre fleece to at least one of T-rolling, knife cutting, scraping, knocking off, brushing or grating for removing layers, in particular surface layers.

[0047] In an embodiment of the method or fabric recycling machine or extraction module disclosed herein, the fluff of the mixed fabric waste fiber material contains an initial concentration range of synthetic fiber material of up to 10%, preferably up to 5%, more preferably up to 3%, more preferably up to 2%; and / or the fluff of the mixed fabric waste fiber material includes or is core yarn fabric waste fiber material; and / or the fluff does not contain blended fabric waste fiber material.

[0048] In embodiments of the method or the fabric recycling machine or the extraction module disclosed herein, the synthetic fiber material is or comprises polyurethane, in particular elastane; and / or the synthetic fiber material is not or does not comprise polyester.

[0049] In an embodiment, the method comprises repeating additional method steps of at least one of: steps a and b in combination, or step c, or step d, or a combination thereof, until recycled natural fibers are obtained of sufficient quality for reuse in a fiber spinning process or other processes (such as weaving, dyeing and finishing), in particular for reuse in a fiber rotor spinning process.

[0050] On the other hand, the present invention relates to a method for recycling fabrics containing mixed yarn waste, in particular fabric waste fiber material containing core yarn or made of core yarn (wherein a flock of mixed fabric waste fiber material containing synthetic fiber material and natural fiber material is formed), including a method for extracting synthetic fiber material from the flock as disclosed herein.

[0051] In another aspect, the present invention relates to a method for retrofitting a fabric recovery machine (1) with an extraction module (2) according to any one of claims 1 to 14, comprising the following method steps:

[0052] a. providing at least one extraction module, each extraction module comprising an electrostatic charging unit and a separation stage, in particular a separation unit,

[0053] b. installing an electrostatic charging unit on the fabric recycling machine (1) and providing electrical power to the electrostatic charging unit, and

[0054] c. Installing the separation stage to the fabric recycling machine and providing electrical power to the separation stage.

[0055] In an embodiment, the electrostatic charging unit is retrofitted to the fine opening stage of the recycling machine; and / or the separating stage is retrofitted to the fine opening stage of the fabric recycling machine.

[0056] It will be understood that both the foregoing general description and the following detailed description present embodiments with optional features and are intended to provide an overview or framework for understanding the nature and features of the present disclosure. The accompanying drawings are included to provide further understanding and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate various embodiments and, together with the description, are used to explain, by example, the principles and operations of the concepts disclosed herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The invention described herein will be more fully understood from the detailed description given below and the accompanying drawings, which merely show or relate to exemplary embodiments and are not to be construed as limiting the invention claimed in the appended claims. In the drawings:

[0058] Figure 1 schematically showing a schematic partial side view of a fabric recycling machine for mixed yarn waste including an extraction module according to an embodiment of the present invention;

[0059] Figure 2 A first flow chart of a method for extracting synthetic fiber material, in particular in a general textile recycling process, is schematically shown.

[0060] Figure 3 A second flow chart of a method for extracting synthetic fiber material, in particular in a general textile recycling process, is schematically shown.

[0061] Figure 4 schematically shows a schematic partial side view of an extraction module according to an embodiment of the present invention;

[0062] Figure 5 A schematic partial side view of an extraction module according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0063] Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying drawings in which some, but not all, features are shown. The embodiments disclosed herein may be embodied in a variety of different forms, may include variations in one or more features or aspects, and may be generally combined with one another. The embodiments should not be construed as limiting; rather, these embodiments are provided to ensure that the present disclosure will satisfy applicable legal requirements. In general, the same reference numerals shall refer to the same or similar components or parts.

[0064] Figure 1 A schematic and partial side view of a fabric recycling machine 1 is shown, which comprises fine opening stages 1a, 1b, 1c, 1d, in particular first and second combing stages 1a, 1b and third and fourth combing stages 1c, 1d. Therein, there are conveying rollers 10 or inlet or feed rollers 10 for controlled feeding of fiber fleece to the respective subsequent stages 1a, 1b, 1c, 1d. Such conveying rollers 10 may provide negative pressure inside to attract fiber fleece (not shown) and convey it to the next station. In addition, there may be a combing roller 11 or a roller 11 with a specific roller group (such as generally a needle roller, a toothed roller, a wire roller, a combing roller or a conveying roller). There may also be a screen roller 12 or a screening drum 12 or a cleaning roller 12, which provides a screen surface with internal negative pressure, so that dust or waste can fall into the internal volume and can thus be extracted from the fiber fleece.

[0065] According to the invention, there is an extraction module 2. It comprises an electrostatic charging unit 21, which can be configured as a separate submodule 21 for retrofitting to a fabric recycling machine 1. The electrostatic charging module 21 should contain an electric fiber charging device (not shown in detail), such as an electric roller or a triboelectric roller or an electrostatic electrode. In addition, the extraction module 2 comprises a separation stage 22, which can also be configured as a separate submodule 22 for retrofitting to a fabric recycling machine 1. The separation stage 22 can include an inlet roller 220 for receiving the fiber fluff and conveying it to the separation stage 22 in a controlled manner. The separation stage 22 can also include an electric separation device 221, which includes an electric separation field generating device, such as (multiple) electric rollers or triboelectric rollers; can also include a mechanical fiber processing device 222, such as, for example, (multiple) combing rollers, (multiple) drum (tambour) rollers, (multiple) conveying rollers; and can also include a mechanical separation device 223, such as, for example, at least one of the following: a T-roller, a knife, a scraping tool, a knock-off tool, a brush, a brush roller, a grid, or a combination thereof.

[0066] After the electrostatic removal and mechanical extraction of synthetic fiber material from the fiber flock, the clean fiber flock is guided to an outlet channel 3 and conveyed from there as a flock or stream 4 consisting mainly of natural fibers, preferably a cotton fiber stream of high purity suitable for further processing in spinning or other processes (such as weaving, dyeing and finishing, in particular rotor spinning).

[0067] In addition, the recycling machine 1 may include a fine opening or carding stage 1c, 1d, which is equipped with rollers with different types of roller sets or metal pins, as indicated by reference numerals 5 and 6. Herein, carding is a mechanical process of untangling, cleaning and mixing fibers to produce a continuous web or sliver suitable for subsequent processing. This is achieved by passing the fibers between differentially moving surfaces covered with carding cloths. It breaks the locks and unorganized clumps of fibers and then aligns the individual fibers to be parallel to each other.

[0068] Figure 2 A flow chart showing a method for extracting synthetic fiber materials, in particular in a general textile recycling process. In step S1, the fiber flock is charged by an electrostatic charging field. In step S2, an electrostatic separation field is applied to the fiber flock to move the charged synthetic fiber materials toward the surface layer of the fiber flock. In step S3, the fiber flock is mechanically treated to promote the movement of the charged synthetic fiber materials toward the surface layer of the fiber flock. And, in step S4, a layer containing an increased or decreased concentration of synthetic fiber materials, in particular a surface layer containing an increased concentration of synthetic fiber materials, is removed by a mechanical separation device 223.

[0069] Figure 3 An enhanced flow chart is shown, wherein intermittent combing stages are applied alternately or in sub-combinations or together in steps S0, S12 and / or S23.

[0070] In summary, the extraction module 2 is capable of recovering natural fibers of sufficient quality for reuse in spinning, particularly rotor spinning or weaving and similar processes from mixed waste fiber fleece by providing a two-step process for extracting synthetic fiber materials using electrostatic and mechanical means. In particular, the separation stage 22 may include rollers, tumblers and / or drums and an electrical separation field for further moving the charged synthetic fiber material closer to the surface of the fleece. Finally, the removal of the synthetic fiber material is achieved mechanically by removing a surface layer of the fleece containing a rich concentration of synthetic fiber material, or removing a layer of the fleece containing natural fiber material with a reduced concentration of synthetic fiber material.

[0071] Figure 4 An embodiment of the extraction module 2 is shown in more detail, comprising: a feed conveyor belt 8, 80, which is used to transport the fiber fluff 7 containing synthetic fiber material 7a and natural fiber material 7b; an electrostatic charging unit 21, which may include a first electrical device 21a and / or a second electrical device 21b, which is used to charge the fiber fluff 7 and in particular the synthetic fiber material 7a, and / or to move the charged synthetic fiber material 7a closer to the surface of the fiber fluff 7; a separation unit 22, which includes separation devices 221, 222, 223, in particular an electrical separation device 221, a mechanical fiber processing device 222 and a mechanical separation device 223; and an output stage 23, which includes an outlet conveying device, such as a roller 12 and an outlet conveyor belt 81.

[0072] like Figure 4 and Figure 5 As shown in the figure, the electrostatic charging unit 21 may include at least one of the electrical devices 21a, 21b and 21c, so that the synthetic fiber material 7a can be charged; and optionally, the charged synthetic fiber material 7a can also be moved closer to the surface of the fiber fluff 7 (particularly in cooperation with the fiber processing device 222).

[0073] like Figure 4 , the mechanical fiber treatment device 222 may include a combing roller 222 that rotates in the conveying direction 9 of the fiber fleece 7 for combing the fiber fleece 7 and moving it to an electrostatic separation field (not shown) of an electric separation device 221, in particular an electrostatic conveyor belt 221a including a carrier element 221d, for example. In this context, the conveying direction 9 may refer to a forward or main conveying direction 9 of the fiber fleece material 7 through the extraction module 2 of the recycling machine 1.

[0074] The electrostatic conveyor belt 221a may be movable in the conveying direction 9 by a drive 221b (e.g. a drive roller 221b) and may include a charged pickup area 2210a for attracting the charged synthetic fiber material 7a and a discharge area 2211a for discarding the synthetic fiber material 7a (in particular by a brush cleaner 221c or a suction cleaner 221c).

[0075] The mechanical separation device 223 may comprise a counter-rotating roller 223, in particular a brush roller 223, for deflecting the fleece 7 from the electrical separation device 221, in particular the electrostatic conveyor belt 223 (e.g. by moving downwards). Herein, the mechanical separation device 223, in particular the brush roller 223, is arranged below and close to the electrical separation device 221, in particular the electrostatic conveyor belt 221. This allows a first layer, in particular a bulk layer, of the fiber fleece 7 comprising natural fiber material 7b with a reduced concentration of synthetic fiber material 7a, in particular a surface layer, to be separated from a second layer, in particular a surface layer, comprising an increased concentration of synthetic fiber material 7a, the synthetic fiber material 7a at least partially adhering to the electrical separation device 221, preferably the electrostatic conveyor belt 221a.

[0076] When retrofitting a fabric recycling machine 1 with a synthetic fiber extraction module 2 as disclosed herein, the electrical separation device 221, in particular the electrostatic conveyor belt 221, can be placed on top of a combing device 2223, which includes the mechanical fiber treatment device 222 and the mechanical separation device 223. For example, the electrostatic conveyor belt 221 can replace the cover or hood of the combing device 2223.

[0077] In the output stage 23, the roller 12 can be a suction roller 12 or a screening drum 12, which is arranged after the separation stage 22 of the extraction module 2 and serves to re-agglomerate the fiber fleece 7 containing the natural fiber material 7b obtained from the extraction module 2 with increased purity. The roller 12 can rotate in the conveying direction 9 and can convey the fiber fleece 7 towards the outlet conveyor belt 81.

[0078] In an embodiment, depending on the purity level of the natural fiber material 7b, i.e. the residual concentration of the synthetic fiber material 7a contained therein, the outlet conveyor 81 can, for example, convey the fiber fleece 7 to another extraction module 2. Alternatively, the outlet conveyor 81 can convey the purified natural fiber material 7a to an outlet channel 3 (e.g. Figure 1 ), or even available exit channel 3 ( Figure 4 (not shown) replaces the exit conveyor belt 81.

[0079] As Figure 4 Alternatively to or in addition to the embodiments shown in FIG. 1 , the extraction module 2 may include a recovery stage 24 ( Figure 5) for resupplying insufficiently purified fiber fluff material 7, which contains a large residual concentration of synthetic fiber material 7a in addition to natural fiber material 7b. The recovery stage 24 may include a backward conveying device 82, such as a backward conveyor belt 82, which is arranged below the separation stage or unit 22 (in particular the mechanical separation device 223 and / or the mechanical fiber treatment device 222) for collecting insufficiently purified fiber fluff material 7 and conveying it in the backward conveying direction 9b in order to resupply it to the previous or the same extraction module 2.

[0080] Parts List

[0081] 1 Fabric recycling machine

[0082] 1a, 1b fine opening grade, carding grade, first / second carding grade

[0083] 1c, 1d fine opening grade, carding grade, third / fourth carding grade, etc.

[0084] 10 conveyor rollers, inlet rollers, feed rollers

[0085] 11 Combing rollers, rollers with roller groups; needle rollers, toothed rollers, wire rollers, comb brush rollers; conveyor rollers 12 Screen rollers, screening drums, cleaning rollers, vacuum suction rollers (for purified natural fiber materials)

[0086] 2 Extraction module

[0087] 21Electrostatic charging unit, electrostatic charging submodule, electric fiber charging device

[0088] 21a, 21b, 21c Electrical devices

[0089] 22 separation stages, separation units, separation submodules

[0090] 221,222,223 Separation Devices

[0091] 220 entrance roller, feed roller to extraction module

[0092] 221Electrostatic separation device, electrostatic separation field generating device, electrostatic roller, electrostatic separation field

[0093] 221a Electrostatic conveyor belt, electrostatic cover of combing device 2223

[0094] 2210a Charged pickup area for attracting charged synthetic fiber materials

[0095] 2211a Release area for discarding charged synthetic fiber materials

[0096] 221b Drivers and drive rollers for electrostatic conveyor belts

[0097] 221c Cleaner, vacuum cleaner, suction cleaner, brush, synthetic fiber collector 221d Carrier element for electrostatic conveyor belt

[0098] 222 Mechanical fiber processing devices, carding rollers, drum rollers, conveyor rollers

[0099] 223 Mechanical separation devices, T-rollers, knives, scraping tools, knock-off tools, brushes, brush rollers, grilles

[0100] 2223 Combing device comprising a mechanical fiber processing device and a mechanical separation device

[0101] 23Transmission stage, output stage

[0102] 24 recovery stages, re-feed stages

[0103] 3 exit channels

[0104] 4Clean fiber flow, cotton fiber flow

[0105] 5 A first roller with a first type of roller group or metal pins, a first mechanical fiber processing roller, a first toothed roller

[0106] 6 A second roller with a second roller set or metal pins, a second mechanical fiber processing roller, a second toothed roller

[0107] 7. Velvet from mixed fabric waste fiber materials, velvet from core yarn fabric waste fiber materials

[0108] 7Synthetic fiber materials

[0109] 7b Natural fiber materials

[0110] 8. Wool conveying devices, conveying devices, conveyor belts

[0111] 80 Feed conveyor belt, feed conveyor device

[0112] 81Export conveyor belt, export conveyor device

[0113] 82 Backward conveyor belt / device, re-feed conveyor belt / device

[0114] 9 conveying direction, forward conveying direction

[0115] 9b conveying direction, backward conveying direction.

Claims

1. An extraction module (2) for extracting synthetic fiber material (7a) from mixed textile waste fiber material (7a, 7b) comprising synthetic fiber material (7a) and natural fiber material (7b), in particular including or being core yarn waste fiber material, in particular for implementing the method for extracting synthetic fiber material (7a) according to any one of claims 28 to 34, the extraction module (2) comprising: a. an electrostatic charging unit (21) configured to be mounted at a fabric recycling machine (1) for charging the fiber pile (7) of the mixed textile fiber material and / or for moving the charged synthetic fiber material (7a) closer to the surface of the fiber pile (7), and b. A separation stage (22) comprising separation means (221, 222, 223) for removing layers, in particular surface layers, of the fiber fleece (7) containing an increased or decreased concentration of the synthetic fiber material (7a).

2. The extraction module (2) according to claim 1, wherein: The electrostatic charging unit (21) is configured to be installed, in particular retrofitted, at a fine opening stage (1a, 1b, 1c, 1d) of the fabric recycling machine (1).

3. An extraction module (2) according to any one of the preceding claims, wherein: The electrostatic charging unit (21) is configured to be installed, in particular retrofitted, after a carding stage (1a, 1b) of the fabric recycling machine (1).

4. An extraction module (2) according to any one of the preceding claims, the extraction module (2) includes an electrical interface for providing electrical power to the electrostatic charging unit (21), and / or includes a mounting device constructed for installing or modifying the electrostatic charging unit (21) to the fabric recovery machine (1).

5. An extraction module (2) according to any one of the preceding claims, wherein: The separation device (221, 222, 223) comprises an electric separation device (221) for applying an electric separation field to the charged fiber fleece (7) to move or further move the charged synthetic fiber material (7a) closer to the surface of the fiber fleece (7).

6. The extraction module (2) according to claim 5, wherein: The electric separation device (221) includes electrodes for applying the electric separation field to the charged fiber fleece (7), and / or includes an electric roller or an electrostatic conveyor belt (221a) for charging the synthetic fiber material (7a) and / or electrically attracting the charged synthetic fiber material (7a).

7. An extraction module (2) according to any one of the preceding claims, wherein: The separation device (221, 222, 223) comprises a mechanical fiber treatment device (222) for treating the charged fiber flock (7) so as to move the charged synthetic fiber material (7a) further closer to the surface of the flock (7), in particular when exposed to the electrostatic separation field.

8. The extraction module (2) according to claim 7, wherein: The mechanical fiber processing device (222) comprises a combing roller (222) for combing the charged fiber pile (7).

9. The extraction module (2) according to any one of the preceding claims, wherein: The separation means (221, 222, 223) comprises a mechanical separation means (223) configured to remove a surface layer comprising an increased concentration of the synthetic fiber material.

10. The extraction module (2) according to any one of the preceding claims, wherein: The separation means (221, 222, 223) comprises a mechanical separation means (223) configured to remove a layer of the natural fiber material (7b) comprising a reduced concentration of the synthetic fiber material (7a), in particular an opposite surface layer or a bulk layer.

11. The extraction module (2) according to claim 9 or 10, wherein: The mechanical separation device (223) comprises at least one separation tool selected from the group consisting of: a T-roller, a knife, a scraping tool, a knock-off tool, a brush, a brush roll, a grid, or a combination thereof.

12. An extraction module (2) according to any one of the preceding claims, wherein: The separation stage (22) is a separation unit (22) configured to be installed in particular as a retrofit on the fabric recovery machine (1).

13. The extraction module (2) according to claim 12, wherein: The separation unit (22) comprises an electrical interface for providing power to drive the separation device ((221, 222, 223)), and / or further comprises a mounting device for mounting or retrofitting the mechanical separation unit (22) to the fabric recovery machine (1).

14. An extraction module (2) according to any one of the preceding claims, wherein: The separation stage (22) is or comprises a modified component of the recycling machine (1), in particular a fine opening stage or a carding stage (1c, 1d) of the textile recycling machine (1).

15. The extraction module (2) according to claim 14, wherein: The modified parts of the fabric recycling machine (1) include one or more of the following: a roller, which is modified with an electric or triboelectric device to obtain a chargeable roller (221); an electric roller (221), which is modified and installed near the fiber fluff path in the recycling machine (1); an electric separation field generating device (221), which for example includes or is modified and installed near the fiber fluff path in the recycling machine (1) A fixed electrode or an electrostatic conveyor belt (221a); ​​and combinations thereof.

16. The extraction module (2) according to claim 15, wherein: The electric separation field generating device (221) comprises an electrostatic conveyor belt (221a) which can be moved by a drive (221b) and comprises a charged pickup area (2210a) for attracting the charged synthetic fiber material (7a) and a release area (2211a) for discarding the synthetic fiber material (7a), particularly by a brush cleaner or a suction cleaner (221c).

17. The extraction module (2) according to any one of claims 15 to 16, wherein: The electrostatic conveyor belt (221a) is arranged above the mechanical fiber treatment device (222) and / or above the mechanical separation device (223).

18. The extraction module (2) according to claim 5 and any other of the preceding claims, wherein: The mechanical fiber processing device comprises a combing roller (222) which rotates in the conveying direction (9) of the fiber fluff (7) for combing the fiber fluff (7) and moving it into the electrostatic separation field of the electrical separation device (221), in particular the electrostatic conveyor belt (221a).

19. The extraction module (2) according to claim 5 and any other of the preceding claims, wherein: The mechanical separation device comprises a counter-rotating roller (223), in particular a brush roller (223), for separating a first layer, in particular a bulk layer, of the fiber fleece (7) comprising the natural fiber material (7b) having a reduced concentration of the synthetic fiber material (7a) from a second layer, in particular a surface layer, comprising an increased concentration of the synthetic fiber material (7a), in particular when adhered to the electrical separation device, preferably the electrostatic conveyor belt (221a).

20. A fabric recovery machine (1) for processing waste yarn (7) comprising synthetic fiber materials (7a) and natural fiber materials (7b), in particular the fine opening stage or carding stage (1a, 1b, 1c, 1d) of the fabric recovery machine (1), in particular a fabric recovery machine (1) for implementing the method for recovering fabric according to claim 35, wherein the fabric recovery machine (1) comprises or is modified with an extraction module (2) according to any one of the preceding claims 1 to 19.

21. A fabric recovery machine (1) according to claim 20, comprising or retrofitted with two or more extraction modules (2) according to any of the preceding claims 1 to 19.

22. A fabric recycling machine (1) according to any one of claims 20 to 21, wherein: The electric separation field generating device (221), in particular the electrostatic conveyor belt (221a), is installed on the top of the combing device (2223) of the fabric recycling machine (1) and / or replaces the cover of the combing device (2223).

23. A fabric recycling machine (1) according to any one of claims 20 to 22, wherein: The combing device (2223) of the fabric recycling machine (1) comprises the mechanical fiber processing device (222) and the mechanical separation device (223).

24. The fabric recycling machine (1) according to any one of claims 20 to 23, comprising a fluff conveying device (8) for conveying the fluff (7) to and from the extraction module (2), in particular a feed conveyor belt (80), an outlet conveyor belt (81), and optionally, a rear conveyor belt (82) for re-feeding the fluff (7) to at least one of the extraction modules (2).

25. A fabric recycling machine (1) according to any one of claims 20 to 24, comprising a suction roller (12) which is arranged after the separation stage (22) of the extraction module (2) and is used to re-condense the fiber fluff (7) containing the natural fiber material (7b) obtained from the extraction module (2) with increased purity.

26. A fabric recycling machine (1) according to any one of claims 19 to 25, wherein: The extraction module (2) does not comprise pneumatic means for conveying the fleece (7) of the mixed textile waste fiber material (7a, 7b), and / or wherein the extraction module (2) does not comprise chemical means for extracting fiber material components.

27. A fabric recycling machine (1) according to any one of claims 20 to 26, wherein: The synthetic fiber material (7a) is removed from the waste yarn fleece (7) to obtain recycled natural fibers (7b) of sufficient quality to be reused in fiber spinning, in particular fiber rotor spinning.

28. A method for extracting synthetic fiber material from a pile (7) of mixed textile waste fiber material (7a, 7b) comprising synthetic fiber material (7a) and natural fiber material (7b), in particular the method being implemented by an extraction module (2) according to any one of claims 1 to 19 or a textile recycling machine (1) according to any one of claims 20 to 27, the method comprising the following method steps: a. exposing the velvet (7) to an electrostatic charging field (S1) provided by an electrostatic unit (21) for electrostatically charging the synthetic fiber material (7a) in the velvet (7), b. applying an electrostatic separation field (S2) provided by an electric field generating device (221) for moving the charged synthetic fiber material (7a) toward the surface layer of the fleece (7), c. mechanically treating the fleece (7) (S3) by means of a mechanical fibre treatment device (222) for promoting the movement of the charged synthetic fibre material (7a) towards the surface layer of the fleece (7), in particular when the fleece is exposed to the electrostatic separation field, and d. Removing the layer containing the synthetic fiber material (7a) with an increased or decreased concentration by means of separation means (221, 222, 223), in particular mechanical separation means (223).

29. The method according to claim 28, comprising in step d: The surface layer (S4) containing the synthetic fiber material (7a) with an increased concentration is removed by the electrical separation device (221), and / or the relative surface layer or volume layer of the natural fiber material (7b) containing the synthetic fiber material (7a) with a reduced concentration is removed by the mechanical separation device (223).

30. The method according to any one of claims 28 to 29, comprising at least one of the following method steps: a0. Combing the fiber fleece (7) before step a (S0), b0. Combing the fiber fleece (7) after step a and before step b (S12), and c0. Combing the fiber pile (7) (S23) after step b and before step c.

31. The method according to any one of claims 28 to 30, wherein said step d comprises subjecting said fiber fleece (7) to at least one of: T-rolling, knife cutting, scraping, knocking off, brushing or grating for removing said layer, in particular the surface layer.

32. The method according to any one of claims 28 to 31, wherein the initial concentration range of the synthetic fiber material (7a) contained in the fluff (7) of the mixed fabric waste fiber material (7a, 7b) is at most 10%, preferably at most 5%, more preferably at most 3%, more preferably at most 2%; and / or wherein the fluff (7) of the mixed fabric waste fiber material (7a, 7b) includes or is core yarn fabric waste fiber material (7a, 7b); and / or wherein the fluff (7) does not contain blended fabric waste fiber material.

33. The method according to any one of claims 28 to 32, wherein: The synthetic fiber material (7a) is or includes polyurethane, in particular elastane; and / or wherein the synthetic fiber material (7a) is not or does not include polyester.

34. The method according to any one of claims 28 to 33, comprising repeating at least one of the following additional method steps: combined steps a and b, or step c, or step d, or a combination thereof, until the recycled natural fiber (7b) is obtained of a quality sufficient for reuse in a fiber spinning process, in particular a fiber rotor spinning process.

35. A method for recycling fabric containing mixed yarn waste, wherein: Forming a pile (7) of mixed textile waste fiber material comprising synthetic fiber material (7a) and natural fiber material (7b), which in particular includes or is core yarn waste, wherein the method for extracting synthetic fiber material from the pile (7) is performed according to any one of claims 28 to 34.

36. A method for retrofitting a fabric recovery machine (1) with an extraction module (2) according to any one of claims 1 to 19, comprising the following method steps: a. providing at least one extraction module (2), each extraction module (2) comprising an electrostatic charging unit (21) and a separation stage (22), in particular a separation unit (22), b. installing the electrostatic charging unit (21) on the fabric recycling machine (1) and providing electrical power to the electrostatic charging unit (21), and c. Installing the separation stage (22) on the fabric recycling machine (1) and providing electrical power to the separation stage (22).

37. The method of claim 36, wherein: The electrostatic charging unit (21) is retrofitted to the fine opening stage (1a, 1b, 1c, 1d) of the recycling machine (1); and / or wherein the separation stage (22) is retrofitted to the fine opening stage (1a, 1b, 1c, 1d) of the fabric recycling machine (1).

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