METHOD FOR CLEAN FIBER RECOVERY FROM CONTAMINATED ARTICLES

Info

Publication number: 20180202102
Type: Application
Filed: Jul 15, 2016
Publication Date: Jul 19, 2018
Inventors: Kaiyuan Yang (Cumming, GA), Mark B. Majors (Cumming, GA), Udaykumar Raval (Cumming, GA), Anita Neidert (Roswell, GA), Jack Smid (Suwanee, GA)
Application Number: 15/744,461

Abstract

A method (10) for cleaning fibers from a contaminated article is disclosed. The method (10) can include pulping (20) a contaminated article to separate the fibers or filaments from the contaminated article in a first solution to provide dissociated pulped fibers. The method (10) can also include washing (26) the dissociated pulped fibers by forming a suspension comprising the dissociated pulped fibers from the contaminated article and a detergent, applying a magnetic field to the suspension, and mixing the suspension to wash the dissociated pulped fibers while applying the magnetic field to the suspension thereby forming washed pulped fibers. Contaminates can be removed from the suspension while washing (26) the dissociated pulped fibers. The washed pulped fibers can be rinsed and dried to provide clean fibers.

Description

Description

This application claims the benefit of priority from U.S. Provisional Application No. 62/192,737 filed on Jul. 15, 2015.

TECHNICAL FIELD

The present disclosure relates generally to a method cleaning fibers of contaminated articles.

BACKGROUND OF THE DISCLOSURE

Disposable wipes or wipers are often used in place of durable cloths in a variety of cleaning situations and can provide cost advantages over durable cloths. In industrial cleaning settings, disposable wipers are commonly used to clean equipment, machinery, parts, and work surfaces and in the process, may come in contact with and accumulate materials such as industrial oil, solvents, and grease, among others. In such a setting, disposable wipers can provide multiple benefits over durable wipes. For example, disposable wipers can provide a convenience advantage over durable cloths in that the disposable wipers need not be re-washed or decontaminated, whereas durable cloths need to be collected and then sent to traditional cleaning sites for washing and decontamination. Because the durable cleansing clothes often have a variety of contaminates with very different chemical and physical properties, it is difficult to provide a single cleaning method or procedure that can effectively remove all of the contaminates, which can leave some contaminates on the cleansing cloths. Additionally, disposable wipers provide the benefits of providing fresh and soft wiper surfaces for each use, avoiding metal accumulation after repeated uses, and providing potential cost advantages over durable cloths.

However, one obstacle of using disposable wipers in place of durable cloths is that the disposable wipers are typically discarded after becoming soiled and if the wipers contain designated hazardous materials, the disposable wipers must be handled properly in compliance with federal and state hazardous waste regulations. The handling that may be required can include several processing steps such as the collection, storage, and transportation of used wipers. These steps can minimize the benefits and advantages of using disposable wipers over durable cleansing cloths.

Thus, there is a desire for a method for cleaning fibers and/or filaments from contaminated articles, such as disposable wipers, such that the fibers can be recycled instead of being treated and disposed of as solid waste. There is also a desire for a method of recycling fibers and/or filaments from contaminated articles such that the fibers and/or filaments can be reused to manufacture new articles.

SUMMARY OF THE DISCLOSURE

In one embodiment, a method for cleaning fibers from a contaminated article is disclosed. The method can include providing a contaminated article comprising contaminates and at least one of fibers and filaments. The method can also include pulping the contaminated article to separate the at least one of fibers and filaments from the contaminated article in a first solution to provide dissociated pulped fibers. Additionally, the method can include forming a suspension or a slurry comprising the dissociated pulped fibers from the contaminated article and a detergent. The method can also include applying a magnetic field to the pulping or to the suspension or the slurry. The method can further include mixing the suspension or slurry to wash the dissociated pulped fibers while applying the magnetic field to the suspension or slurry thereby forming washed pulped fibers. The method can additionally include removing contaminates from the suspension or slurry. The method of cleaning fibers can further include removing/separating the washed pulped fibers from the suspension or slurry. Furthermore, the method can include rinsing the washed pulped fibers after removing the washed pulped fibers from the suspension or slurry to provide rinsed pulped fibers. The method can further include drying the rinsed pulped fibers to provide clean fibers.

In another embodiment, a method for cleaning fibers from a contaminated article is disclosed. The method can include providing a contaminated article comprising contaminates and at least one of fibers and filaments. The contaminates can include at least one of oils, greases, solvents, adhesives, and lubricants. The method can also include pre-washing the contaminated article in a pre-washing solution. The method can further include adding prescribed amounts of detergent across one or more steps. Additionally, the method can include pulping the contaminated article in a first solution to separate the at least one of fibers and filaments from the contaminated article to provide dissociated pulped fibers. The pre-wash solution and the first solution can be heated. The method can include heating at one or more of the steps. The method can further include applying a magnetic field to the pre-wash, or to the first solution while pulping the contaminated article to provide dissociated pulped fibers. The method can also include filtering the dissociated pulped fibers from the first solution after pulping the contaminated article. Furthermore, the method can include rinsing the dissociated pulped fibers after filtering the pulped fibers from the first solution. The method can also include forming a suspension comprising the dissociated pulped fibers from the contaminated article and a detergent in a second solution. Also, the method can include applying a magnetic field to the second solution. The method can additionally include mixing the suspension to wash the dissociated pulped fibers while applying the magnetic field to the suspension thereby forming washed pulped fibers. The method can include skimming the surface of the suspension to remove contaminates. Furthermore, the method can include rinsing the washed pulped fibers after removing the washed pulped fibers from the suspension to provide rinsed pulped fibers. The method can further include an acid treatment to washed and pulped fibers and then followed by a neutralization step to make the pH of the recycled fibers to close to neutral (e.g., approximately pH 7.0). The pH adjustment solution can be heated. The method can include rinsing the treated pulped fibers to provide further rinsed pulped fibers. Additionally, the method can include drying the further rinsed pulped fibers to provide clean fibers.

BRIEF DESCRIPTION OF DRAWINGS

A full and enabling disclosure thereof, directed to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, which makes reference to the appended figures in which:

FIG. 1 is a process schematic providing an exemplary embodiment of a method for cleaning fibers from a contaminated article.

FIG. 2 is a representation of surfactant-separated polymeric fibers/oil/grease and pulp fibers in water.

FIG. 3A is a representation of (excess) surfactant binding polypropylene/oil/grease and pulp fibers.

FIG. 3B is a representation of (excess) surfactant directly binding oil/grease and pulp fibers.

FIG. 3C is a representation of (excess) surfactant binding polypropylene fibers and pulp fibers.

Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

In an embodiment, the present disclosure is generally directed towards a method for cleaning fibers from a contaminated article. Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment or figure can be used on another embodiment or figure to yield yet another embodiment. It is intended that the present disclosure include such modifications and variations.

When introducing elements of the present disclosure or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Many modifications and variations of the present disclosure can be made without departing from the spirit and scope thereof. Therefore, the exemplary embodiments described above should not be used to limit the scope of the invention.

Definitions

The term “contaminates” refers herein to solids and fluids, both organic and inorganic that can be absorbed, adsorbed, or contained by an article. Exemplary contaminates can include, but are not limited to, pure metals and alloys, which can be in the form of particles from metallic surfaces; hybrid inorganic and organic composites and mixtures, such as greases, lubricants and surface coatings; inorganic materials, such as metal halides, sulfates, carbonates, hydroxides, sulfides, metal oxides, organometallics, ceramics; and organic materials, such as liquid organic solvents, oils, and grease without lubricants.

The term “hydrophilic” refers herein to fibers or the surfaces of fibers which are wetted by aqueous liquids in contact with the fibers. The degree of wetting of the materials can, in turn, be described in terms of the contact angles and the surface tensions of the liquids and materials involved. Equipment and techniques suitable for measuring the wettability of particular fiber materials or blends of fiber materials can be provided by Cahn SFA-222 Surface Force Analyzer System, or a substantially equivalent system. When measured with this system, fibers having contact angles less than 90 are designated “wettable” or hydrophilic, and fibers having contact angles greater than 90 are designated “nonwettable” or hydrophobic.

The term “meltblown” refers herein to fibers formed by extruding a molten thermoplastic material through a plurality of fine, usually circular, die capillaries as molten threads or filaments into converging high velocity heated gas (e.g., air) streams which attenuate the filaments of molten thermoplastic material to reduce their diameter, which can be a microfiber diameter. Thereafter, the meltblown fibers are carried by the high velocity gas stream and are deposited on a collecting surface to form a web of randomly dispersed meltblown fibers. Such a process is disclosed, for example, in U.S. Pat. No. 3,849,241 to Butin et al., which is incorporated herein by reference. Meltblown fibers are microfibers which may be continuous or discontinuous, are generally smaller than about 0.6 denier, and may be tacky and self-bonding when deposited onto a collecting surface.

The term “nonwoven” refers herein to materials and webs of material which are formed without the aid of a textile weaving or knitting process. The materials and webs of materials can have a structure of individual fibers, filaments, or threads (collectively referred to as “fibers”) which can be interlaid, but not in an identifiable manner as in a knitted fabric. Nonwoven materials or webs can be formed from many processes such as, but not limited to, meltblowing processes, spunbonding processes, carded web processes, hydroentangling processes, etc.

The term “spunbond” refers herein to small diameter fibers which are formed by extruding molten thermoplastic material as filaments from a plurality of fine capillaries of a spinnerette having a circular or other configuration, with the diameter of the extruded filaments then being rapidly reduced by a conventional process such as, for example, eductive drawing, and processes that are described in U.S. Pat. No. 4,340,563 to Appel et al., U.S. Pat. No. 3,692,618 to Dorschner et al., U.S. Pat. No. 3,802,817 to Matsuki et al., U.S. Pat. Nos. 3,338,992 and 3,341,394 to Kinney, U.S. Pat. No. 3,502,763 to Hartmann, U.S. Pat. No. 3,502,538 to Peterson, and U.S. Pat. No. 3,542,615 to Dobo et al., each of which is incorporated herein in its entirety by reference. Spunbond fibers are generally continuous and often have average deniers larger than about 0.3, and in an embodiment, between about 0.6, 5 and 10 and about 15, 20 and 40. Spunbond fibers are generally not tacky when they are deposited on a collecting surface.

The term “wiper” or “wipe” refers herein to a non-woven or woven article generally used in cleaning or wiping applications. “Wipers” or “wipes” generally include at least some percentage of pulp fibers, but a non-woven or woven article including no pulp fibers can be a “wiper” or “wipe” as used herein. “Wipes” and “wipers” as discussed herein can include fibers and/or filaments other than pulp fibers, including, but not limited to, polypropylene staple fibers or filaments. Exemplary “wipers” or “wipes” include industrial cleaning wipers and paper towels. The term “wiper” can be synonymous with “wipe.”

Referring to FIG. 1, an exemplary method 10 for cleaning fibers from a contaminated article is illustrated. The method 10 can include providing a contaminated article comprising contaminates and at least one of fibers and filaments. While the method 10 discussed herein can be conducted for a single wiper, it is preferable to clean fibers from a plurality of contaminated articles simultaneously for efficiency purposes. The method 10 as discussed herein can be conducted on a small scale (e.g., several grams to several hundred grams) or can be scaled up to a commercial operation for cleaning fibers from larger quantities of contaminated articles (e.g., several hundreds of kilograms to several tongs or more). Some of the exemplary discussion provided herein was for testing conducted at a small scale.

In an embodiment, the contaminated article can be a used wiper, or wipe. For example, small scale testing was conducted according to the method 10 using twenty contaminated WypAll* industrial wipers manufactured by Kimberly-Clark Professional (approximately 10 grams for the dry weight of each clean wiper with approximately 10 grams of contaminates). The WypAll* industrial wiper manufactured by Kimberly-Clark Professional include about 80-85% pulp fibers and about 15-20% spunbond polypropylene fibers. Thus, in one embodiment, the method 10 can be utilized for cleaning a non-woven article including pulp fibers and polymer fibers, however, the method 10 can also be utilized for cleaning contaminated articles including pulp fibers and polymeric filaments, 100% pulp fibers, or 100% polymeric fibers and/or filaments. The WypAll* industrial wiper includes a ratio of pulp fibers to polymeric fibers of about 5.67, but the method 10 discussed herein could be used to clean contaminated articles including other ratios of pulp fibers to polymeric fibers or filaments. In preferred embodiments, the method 10 can be used with contaminated articles including about 10-100% pulp fibers and about 0-90% polymeric fibers or filaments, more preferably about 50-100% pulp fibers and about 0-50% polymeric fibers or filaments. Thus, it is contemplated that the contaminated article used in the method 10 discussed herein could include non-woven articles including ratios of pulp fibers to polymeric fibers or filaments of at least about 0.10, more preferably, at least about 0.50, and even more preferably, at least about 1.0.

The method 10 can include pre-sorting and/or pre-washing 12 the contaminated article(s). In pre-sorting and pre-washing 12, the contaminated article(s) are first screened and sorted to separate fibers from other non-fiber objects such as metal parts, plastic parts, containers, etc. that are discarded together by the generators of said contaminated articles. The screening and/or sorting can be done either manually or by an automated process with metal separation capabilities such as applying a magnetic field. The pre-screened and sorted contaminated articles can then be placed in a container in a pre-washing solution and agitated. The pre-washing solution can be water. For example, the pre-washing 12 conducted in the testing involved placing the twenty contaminated wipers into a container with nineteen liters of clean water and stirred by using a plastic or metal rod for about ten to fifteen minutes. Pre-washing 12 can cause some contaminates, such as oils, greases, and organics, to be released and rise to the top of the pre-washing solution, while other contaminates, such as metal shavings, saw dust, inorganics, and dirt can drop to the bottom of the pre-washing solution in the container. In some cases, per-sorting and pre-washing can be combined in a single step. For example, a magnetic field can be combined with a pre-wash system so that metals can be separated during washing.

In some implementations, pre-washing 12 includes using detergent in the pre-washing solution in specifically prescribed amounts—detergents are further described below with respect to washing 26. For example, this prescribed amount of detergent can be quantified as a weight ratio of detergent to wipes. The detergent added here can be in solid state or in a liquid form. For convenience the weight ratios described herein generally refer to the weight ratios of real detergent actives in solid or liquid detergents to the weight of the contaminated wipers. For example, a liquid detergent is generally composed of a solvent (or a solvent mixture) such as water and real actives, and often the solvent is the main component of the detergent liquid, e.g. as high as 99%. Additionally, it should be understood here that the actives in a detergent can be a single active or a mixture of different actives in any desired ratios. As such, the weight ratio of detergent to contaminated wipers is generally referred to the ratio of the total detergent actives to contaminated wipers. In some implementations this ratio is in the range of 0.0025 to 0.10 and more preferably in the range of 0.01 to 0.10. Further, as discussed below and shown in Table A, preferably the detergent can be used in multiple steps of method 10 such that the cumulative amount of detergent used across these multiple steps is within the above range. For example, in addition or alternative to the pre-washing step 12, detergent can be added at steps 20 (pulping), 26 (washing), or repeat 26 if necessary, or some combination thereof.

As not to be bound by theory, it is believed that excess detergent inhibits the separation of hydrophobic components (e.g., polymeric fibers/oils/grease) and hydrophilic components (e.g., pulp fibers). Using the low prescribed amounts of detergent is believed to encourage the hydrophobic and hydrophilic micelles stay in their separated states or reduce the likelihood of the micelles binding, which, in turn, facilitates the cleaning process of method 10 and otherwise described herein. FIG. 2 is a representation 200 of separated polymeric fibers/oil/grease 202 and pulp fibers 204 in water 206.

FIG. 3A is a representation 300 of (excess) surfactant 302 forming binding links between the first micelle on the left and the second micelle on the right. The first micelle has polypropylene/oil/grease 304 in the middle and surfactant 302 hydrophilic heads pointing outside while the second micelle with pulp fibers 306 in the middle and surfactant 302 hydrophobic tails pointing outside. FIG. 3A shows the link created by the surfactant 302 in the excess detergent (e.g., detergent above the ranges prescribed herein) between the hydrophobic surfactant tail 303 binding to (e.g., attracted to) the hydrophobic polypropylene/oil/grease 304 and the hydrophilic surfactant head 305 binding to (e.g., attracted to) the hydrophilic pulp fibers 306. It is believed the binding caused by the excess surfactant 302 inhibits the separation of the polypropylene/oil/grease 304 and the pulp fibers 306, and thus inhibits the cleaning method 10. Further, the excess surfactant 302 can directly bind the hydrophobic polypropylene/oil/grease 304 to the hydrophilic pulp fibers 306.

FIG. 3B is a representation 308 of (excess) surfactant 310 directly binding oil/grease 312 and pulp fibers 314. More particularly, FIG. 3B shows the hydrophobic tail 309 of the excess surfactant 310 binding to the hydrophobic oil/grease 312 and the hydrophilic head 311 of the excess surfactant 310 binding to the hydrophilic pulp fibers 314, which inhibits the separation of the oil/grease 312 from the pulp fibers 314.

FIG. 3C is a representation 316 of (excess) surfactant 318 binding polypropylene fibers 320 and pulp fibers 322. More particularly, FIG. 3C shows the hydrophobic tail 319 of the surfactant 318 binding to the hydrophobic polypropylenes fibers 320 and the hydrophilic head 321 of the surfactant 318 binding to the hydrophilic pulp fibers 322 thereby creating an undesired link between the pulp fibers 322 and the polypropylene fibers 320. Managing the amount of detergent used reduces the likelihood of the above-described excess surfactant linking.

Further, in some implementations, the pre-washing step, pulping, washing and/or rinsing step(s) or more generally any step(s) using detergent is performed at a solution temperature of above 50° C. and preferably in the range of 65° C. to 95° C. It is believed that raising the temperature to these ranges can reduce the amount of detergent required as compared with the process performed at lower temperatures, and improve the diffusion of the cleaning solution into grease/adhesives/sealants for forming micelles.

Many common grease/adhesives/sealants/oils include surfactants, which are sometimes referred to as, for example, thickeners or surface active agents. Although these inherent surfactants aren't likely enough to forego adding additional detergent to the method 10, they can be utilized to reduce the amount of detergent needed. Example surface active agents/thickener(s) include but are not limited to calcium stearate, sodium stearate, lithium stearate, lithium 12-hydroxystearate, as well as mixtures of these components. In addition to traditional surfactants, some grease and adhesives use solid additives including graphite, molybdenum disulphide, limes, and others. These agents/thickeners can be polar or mixed with polar components (e.g., water) such that they also can help to attract water into grease and other contaminates for forming micelles and facilitating the cleaning process and method 10. Particularly, the penetration of water into interior of a, for example, oil/grease particle/aggregate with the help of thickener/detergent helps to break down oil/grease particles/aggregates so that they can be detached from fiber surfaces and then into water phase to encourage the cleaning process herein.

Table A, from small scale testing, shows the effect of prescribed detergent use. More particularly, Table A shows that using excess detergent in a single step (e.g., detergent actives to dirty wipe ratio at 0.30) is not very effective for reducing the oil/grease levels in comparison to partitioning the detergent into several small portions and then using those partitions in several steps. For example, by using less total detergent in three steps (e.g., from 0.30 in a single step to 0.075 in three steps, for example, 0.03 in step 1, 0.03 in step 2, and 0.015 in step 3), the cleaning efficacy can be improved significantly (e.g., from residue 36,500 to 2,140).

TABLE A Weight Ratio of Added Detergent Added in Oil &Grease Residue Detergent and Used Single or Multiple from Recycled Dry Fibers Detergent Wipes (kg/kg) Steps (ppm) No Detergent No Detergent No Detergent 115,000 An aqueous detergent 0.30 A Single Washing 36,500 with three actives: Step C12-15 Ethoxylated 0.075 Three Washing 2,140 Alcohols (~5-10%) Steps: C14-15 Ethoxylated Step 1: 0.03 Alcohols (~5-10%) Step 2: 0.03 Sodium Carbonate (~5-10%) Step 3: 0.015 Note: The weight of the detergent is the total weight of actives and water.

While preferred, the pre-sorting and/or pre-washing 12 of the contaminated article(s) is not necessary to the method 10 described herein. The excess pre-washing solution 14 used in pre-washing 12 can be directed to a waste-water facility 16 for further processing.

The method 10 can also include cutting 18 the contaminated article(s) to reduce the size of the contaminated article(s). In the small scale testing conducted using the wipers, the pre-washed wipers were removed from the container after pre-washing 12 and the wipers were cut into a plurality of rectangular pieces using a paper cutter. Cutting 18 of the contaminated article(s) during method 10 is merely optional.

The method 10 can also include pulping 20 the contaminated article(s). Pulping 20 of the contaminated article(s) can be conducted by placing the contaminated article(s) in a solution, which can be water, and agitating and mixing the contaminated article(s) to separate the fibers from the contaminated article(s) to provide dissociated pulped fibers.

Pulping 20 can be done by utilizing different pulping tools, depending upon the amount of wipers to be pulped, the fibers comprising the contaminated wipers (e.g., short fibers or continuous fibers), and the manufacturing methods involved (e.g. air-laid or wet-laid with latex or wet strength enhancers as binders, or hydroentangled or co-formed webs with pulp fibers and continuous filaments, etc). For wipers with only pulp fibers or wipers with pulp and staple fibers, traditional pulpers commonly used in paper industry such as Hollander types or (or Valley beaters) are preferred. In some cases, simple blenders commonly used in food industry may be sufficient for pulping 20 a small amount of wipers with only pulp and staple synthetic fibers.

In some circumstances, pulping 20 for wipers with continuous filaments (with or without pulp fibers) may not be efficiently pulped by using traditional pulpers used in paper industry as continuous filaments may not be easily broken or cut to short staple fibers. In these instances, special pulpers, such as Tornado types of pulpers, are required to break and/or cut down the continuous filaments to short staple fibers. Tornado pulpers are known to have specially designed motors as well as fiber stretching and cutting mechanisms so that continuous filaments in the wipers can be stretched/cut/pulped.

In a preferred embodiment, the solution is heated during the pulping 20 of the contaminated article(s), and more particularly, it is preferable to heat the solution to at least about 50° C. Not to be by bound by theory, but it is believed that heating the solution for the pulping 20 provided benefits to help relax the fibrous structure matrix and also increase the solubility as well as the dispensability of both organic and inorganic contaminates in the solution. In particular, contaminated article(s) including polymeric fibers (e.g., spunbond polypropylene fibers) can be softened by such heat, and the softening can lead to relaxation of reduction of entanglement among fibers in the article(s). In the testing conducted on a small scale, the pulping 20 was performed on the cut, rectangular pieces of the wipers using a Hollander Beater by mixing the pieces of the wipers in twenty-two liters of water that was heated to 60° C., and pulped for approximately ten minutes.

Additionally, the pulping 20 of the wipers can be performed within a magnetic field to remove contaminates as they are released from the contaminated article(s) during pulping 20. Not to be bound by theory, but it is believed that a magnetic field can be advantageous over (or in addition to) detergents or other traditional cleaning means in removal of water-insoluble and/or heavily colored metal containing contaminates from pulped slurries. Traces of metal containing contaminates with strong magnetic susceptibility may be present in at least some of the used wipers, if not at least a majority of the wipers, because of potential for direct contact with various industrial machine parts, or metal, ceramic, or other inorganic coated surfaces that are frequently cleaned.

Without limiting to certain specific metals such as magnetically susceptible metals or other forms of iron, nickel, iron oxides, nickel oxides, iron or nickel containing ceramics, such traces of metal containing contaminates with strong magnetic susceptibility can function as the “seeds” for the magnetic removal of metal containing contaminates with weak magnetic susceptibility. The “seeds” as used herein can mean that when metal containing contaminates with strong magnetic susceptibility are in mixed states with other metal-containing contaminates with weak magnetic susceptibility, the metal containing contaminates with strong magnetic susceptibility will bring at least some of the metal-containing contaminates with weak magnetic susceptibility to the magnet surface so that the latter can also be magnetically removed. As used herein, mixed states can mean that they are either physically aggregated together by charge-charge interactions or bound together by the existence of oil and grease. Here, oil and grease, particularly the adhering, or sticky, portions of oil and grease, can effectively function as a binder or a trap to harbor together any metal containing contaminates with varied magnetic susceptibilities.

The “seeds” function has further implications in terms of helping the removal of metal containing lubricants that are commonly pre-added into various industrial oils and greases. Examples of these pre-added lubricants include, but are not limited to, molybdenum-based sulfides (e.g., MoS₂) and their organometallic derivatives such as oil-soluble molybdenum thio-phosphates and thio-carbamates. These pre-added lubricants, particularly MoS₂and its derivatives, are among the hardest metal-containing contaminates to be removed from used wipers because they are so stable to traditional cleaning methods such as high temperatures, oxidants, acids, and detergents. However, the sulfur layers in MoS₂structures have a strong affinity for metallic surfaces and some of these sulfur atoms are available to interact and/or react with metal surfaces such as gold and iron, and thus, magnetically susceptible aggregates between metal shavings or saw dust and MoS₂can be formed when oils and/or grease from metallic surfaces were transferred onto wipers during cleaning.

It is preferable to use a magnetic field strength during pulping 20 of at least about 5000 Gauss on the magnet surface. For example, the magnetic field used in the pulping 20 of the wipers for the small scale testing conducted was created by two bar type neodymium rare earth magnets, one inch in diameter and ten inches long, available at Amazing Magnets. The exemplary magnets used each included multiple individual magnets assembled in a stainless steel tube with like poles opposing one another. The bar type rare earth magnets used were each rated to provide a surface magnetic field strength of at least 10000 Gauss on at least some parts of the stainless steel tube surface of the magnet. During the pulping 20, the magnets were placed in the Hollander Beater to collect as many contaminates as possible, including metal shavings, oils, greases, and inorganics. Of course, it is contemplated that the magnetic field could also be generated by providing an electromagnetic field as an alternative to, or in addition to, one or more magnets. Use of such a magnetic field during the pulping 20 stage is optional in method 10.

The method 10 can also include filtering 22 the dissociated pulped fibers and contaminates. When pulping 20 the wipers, the dissociated pulped fibers and contaminates can form a dark or other colored slurry depending upon the colors of the contaminants. After pulping 20 the wipers, the dissociated pulped fibers and contaminates in the solution can be put through a filtering 22 process to help remove some of the contaminates from the solution that are mixed or suspended or forming emulsified oil/grease/water droplets in the solution. In particular, the filtering 22 under pressure can remove light oils and soil oil/grease/lubricant particles that are already mixed and/or suspended. During or after filtering 22 the dissociated pulped fibers, the dissociated pulped fibers can also be rinsed. The excess solution 24 after filtering 22 (with or without rinsing) can be sent to a waste-water facility 16 for further processing. The filtering 22 can be accomplished by running the dissociated pulped fibers, contaminates, and solution through a sieve, or any other known filtering equipment. Filtering 22 the dissociated pulped fibers, while preferred, is not a required aspect of the disclosure.

The method 10 can further include washing 26 the dissociated pulped fibers of the contaminated article(s) to provide washed pulped fibers. After filtering 22, the dissociated pulped fibers can be combined with a detergent and a solution to form a suspension. The suspension can be held within a container and the solution used during washing 26 can be water. The small scale process for method 10 included combining the dissociated pulped fibers with twelve liters of water with the desired amount of detergent. Washing 26 can include mixing the suspension that includes the dissociated pulped fibers and the detergent in the solution, for example, mixing with a mechanical mixer at a speed to effectively swirl and agitate the suspension in the container. In the small scale testing conducted, the mixing was performed using a variable RPM Lightening Mixer, although any equipment capable of adequately mixing the suspension can be used in the washing 26 of method 10.

In a preferred embodiment, the solution added to the suspension for washing 26 is heated, and more particularly, it is preferable to heat the solution to at least about 50° C. Not to be bound by theory, but it is believed that heating the solution for washing 26 can help provide benefits to fibrous structure matrix of any dissociated pulped fibers that may still be entangled or woven, and can also increase the solubility as well as the dispensability of both organic and inorganic contaminates in the solution.

Sample detergents that can be used include detergents, surfactants, or surfactant combinations that are commonly used for oil and grease cleaning or in personal care hygiene and cleaning products. Such surfactant or surfactant combinations can be selected from any of the following exemplary surfactant families: anionic, cationic, carboxylic, zwitterionic, and non-ionic series of surfactants and their combinations. Specific examples include, but are not limited to tritons, sodium stearates, alkyl benzenesulfonates, lignin sulfonates, dipropylene glycol methyl ethers, and alcohol ethoyxlates.

Although the above mentioned surfactant types may all suitable for the washing 26 described herein, the cleaning efficacy and the amount used for reaching the said cleaning efficacy may vary based on the surfactant or detergent used, for example, as described above with respect to detergent use in the pre-washing step 12. In some cases, cleaning temperature and cleaning time may also be different depending on the surfactant or detergent used. However, preferred surfactant systems that are suitable for the washing 26 described herein should be effective to handle heavy and sticky portions of oils and grease, which in some used wipers can be up to or even double the wiper's fiber weight (e.g., a 10 gram clean wiper may absorb/wipe up to 10-20 grams of oils/grease). The heavy and sticky portions of oils/grease often consist of high molecular weight hydrophobic polymers (e.g., polybutenes, silicones, polyurathanes, fluorocarbon polymers, etc.) that will require surfactants to have strong hydrophobic affinities to them. Accordingly, surfactant systems that have long hydrophobic side alkyl chains will generally perform better than others.

One example of such surfactants, as described in Table A include is a family of alcohol ethoxylates (AEs), in which a long side alkyl chain usually has 12 to 15 carbon atoms and also combined with some ethylene oxide units (3 to 14). In another embodiment, a sample detergent that can be used in the washing 26 described herein is a mixture of alcohol ethoxylates (AEs) with C12-15 alkyl side chains and di-propylene glycol methyl ether at about ratios ranges of 1:5 to 1:40 (or generally referred it to Surfactant Chemistry A or SC A). Di-propylene glycol methyl ether is an organic solvent, but is fully soluble in water so that it can help further for breaking down “heavy & sticky” portions of oils/grease.

When washing 26 the dissociated pulped fibers, the method 10 can include applying a magnetic field to the suspension. It is preferable to use a magnetic field strength during washing 26 of at least about 5000 Gauss. The magnetic field can be created by at least one magnet. In the small scale testing conducted, two bar type neodymium rare earth magnets were used, each being one inch in diameter and ten inches long, available at Amazing Magnets. The exemplary magnets used each included multiple individual magnets assembled in a stainless steel tube with like poles opposing one another. The bar type rare earth magnets used were each rated to provide a surface magnetic field strength of up to 10400 Gauss on at least some parts of the stainless steel tube surface of the magnet. The magnet(s) used to provide the magnetic field during washing 26 are preferably placed in the container such that each of the magnets are at least partially submerged in the suspension. Preferably, the magnet(s) are disposed and held near the sides of the container, so as to avoid interference with the mixing of the suspension during washing 26. Of course, it is contemplated that the magnetic field could also be applied to the suspension by providing an electromagnetic field as an alternative to, or in addition to, one or more magnets.

When washing 26 the dissociated pulped fibers while applying a magnetic field to the suspension, contaminates can begin to accumulate near the top of the suspension. The method 10 can include removing the contaminates from the suspension as part of the washing 26 of the dissociated pulped fibers. In the small scale testing conducted, the contaminates rising to the top surface of the suspension were removed by skimming the surface of the suspension with a scraper, which can be repeated as more contaminates build on the surface of the suspension. The more contaminates that can be removed from the suspension by skimming the surface provides less contaminates for further processing of the dissociated pulped fibers in the method 10. In the small scale testing conducted, the contaminates rising to the top surface of the suspension were substantially used oils 28, which can be collected separately and recycled, as illustrated in FIG. 1.

Additionally, some contaminates can begin to accumulate on the magnets due to the magnetic field being applied to the suspension when washing 26 the dissociated pulped fibers in the suspension. In the small scale testing conducted, it was found that the substantial majority of contaminates accumulating on the magnets were solid, such as metal contaminates and some fibers, mainly staple fibers from pulped spunbond. Because of the hydrophobic nature of pulped spunbond fibers, they have much higher affinity to oil/grease than pulp fibers, and as such, the pulped spunbond fibers can be part of the oil/grease/metal containing contaminate aggregates that can be pulled onto a magnetic surface through the interactions of magnet and “seed” metal containing contaminates with strong magnetic susceptibility. Additionally, the pulped spunbond fibers can have traces of inorganic additives either inherited from polymer manufacturing or added during fiber spinning. These traces of added inorganics can further enhance the magnetic susceptibility of spunbond fibers. As the contaminates accumulate on the magnet(s) (either directly to the magnet surface and/or indirectly via hydrophobic fibers that are attracted themselves to the magnets), the magnets can periodically be removed from the suspension and wiped to remove contaminates from the suspension.

Advantageously, applying a magnetic field while washing 26 the dissociated pulp fibers with detergent can remove a wide variety of contaminates from the suspension. As noted above, if the contaminates include metal or other particles having intrinsic magnetic properties, then the magnetic field being applied during washing 26 can attract not only such particles, but also hydrophobic fibers including contaminates. Therefore, even if the contaminated article(s) includes contaminates in which the substantial portion of contaminates do not include metal particles or particles having intrinsic magnetic properties (e.g., oil, grease, solvents, and lubricants), applying a magnetic field to the suspension during washing 26 can help to remove more contaminates than only using a detergent during washing 26. In some circumstances, the contaminated article(s) can include contaminates devoid of metal particles or particles having intrinsic magnetic properties (e.g., oil, grease, solvents, and lubricants), yet applying a magnetic field to the suspension while washing 26 can help to remove more contaminates than using only a detergent during washing 26.

The washing 26 of the dissociated pulped fibers can occur for a time period sufficient to wash the dissociated pulped fibers. In a preferred embodiment of method 10, the magnetic field can be applied to the suspension the majority of the time period that the washing 26 occurs. In the small scale testing conducted, the washing 26 was conducted for thirty minutes. The contaminated solution 30 and detergent from the suspension after washing 26 can be put through a filtering mechanism and transferred to a waste-water facility 16 for further processing to remove the washed pulped fibers from the suspension.

After washing 26 the dissociated pulped fibers to provide washed pulped fibers, the method 10 can preferably include rinsing 32 the washed pulped fibers to remove excess detergent used in the washing 26 of the dissociated pulped fibers discussed above. The rinsing 32 can also provide the benefit of removing any contaminates confined in the washed pulped fibers that were not transferred in the contaminated solution 30 to the waste-water facility 16. In the small scale testing conducted, the rinsing 32 was performed in a wash box with the assistance of a vacuum with twelve liters of water. As illustrated in FIG. 1, the rinsing solution 34 can also be transferred to a waste-water facility 16 for further processing. In some embodiments, it may be preferable to perform the rinsing 32 several times.

In preferred embodiments, the method 10 can include treating 36 the washed pulped fibers with a pH adjustment solution to provide treated pulped fibers. Treating 36 the washed pulped fibers can occur after the washed pulped fibers are removed from the wash box used in rinsing 32 the washed pulped fibers if rinsing occurred 32. Alternatively, the treating 36 can occur in the same wash box used in rinsing 32 the washed pulped fibers. Treating 36 the washed pulped fibers in a pH adjustment solution can further remove metal contaminates, especially homogeneous metal ions and pH sensitive metal oxides and other metal compounds that can become soluble in a pH adjustment solution. The treating 36 can include adding the washed pulped fibers to a pH adjustment solution and mixing the washed pulped fibers in the pH adjustment solution.

In one embodiment, the pH adjustment solution can include a simple acid such as adding pre-made solutions of hydrochloric acid, sulfuric acid, and/or other pH adjustment agents such as uronium hydrogen sulfate, an acid-base adduct of urea and sulfuric acid. The uranium hydrogen sulfate can further enhance the removal of contaminates as it can also function as a chelation agent to metal ions. The chelation can bring more ions from pulped fibers to water solutions so that they can be removed from fibers. In another aspect, it can be expected that residual uronium hydrogen sulfate left in recycled fibers may have some antimicrobial activity, which may be beneficial to recycling pulp fibers as mold growth can be prohibited.

In the small scale testing conducted, the treating 36 included adding the washed pulped fibers to a pH adjustment solution created by mixing twelve liters of water and adjusting the pH to about 2.0 to about 2.5 by adding a solution including uranium hydrogen sulfate. The pH adjustment solution can be heated (preferably to at least about 50° C.), and in the small scale testing conducted, was heated to about 60° C. to about 65° C. The washed pulped fibers were mixed for approximately thirty minutes in the small scale testing conducted with the aid of a variable RPM Lightening Mixer. The used pH adjustment solution 38 can be put through a filtering mechanism and directed to a waste-water treatment facility 16 for further processing.

If the method 10 includes treating 36 the washed pulped fibers with a pH adjustment solution, the method 10 can also preferably include a neutralization step to help bring the fiber pH back to neutral range (e.g. ˜pH 7.0). The neutralization can be performed, for example, by adding a sodium hydroxide solution (for example a one molar solution or a carbonate or phosphate buffer solution as commonly used in pH control situations) to the fibers after pH adjustment step. The neutralization can be monitored by monitoring pH by either using a pH paper or a pH monitoring device. Alternatively, the neutralization can be performed, for example, by rinsing 40 the treated pulped fibers after the pH adjustment step as rinsing water itself is generally at pH levels of ˜pH 7.0 and continued rinsing can bring the fiber pH back to neutral. Similar to the discussion above regarding rinsing 32 the washed pulped fibers after washing 26, rinsing 40 the treated pulped fibers can occur in a wash box with the assistance of a vacuum. In the small scale testing conducted, the rinsing 40 was completed using twelve liters of water. In some embodiments, the wash box can be the same wash box that the washed pulped fibers were rinsed in. In other embodiments, the rinsing 40 of the treated pulped fibers can occur in a different wash box or rinsing mechanism. The rinsed solution 42 from rinsing 40 the treated pulped fibers can be directed to a waste-water treatment facility 16 for further processing.

The method 10 can also include drying 44 the pulped fibers to provide clean fibers. Depending on the steps utilized in method 10, drying 44 to provide clean fibers can occur after different sub-process of the method 10. For example, the drying 44 can be performed on the rinsed pulped fibers after rinsing 32 the washed pulped fibers from washing 26 if the steps of treating 36 with a pH adjustment solution, and rinsing 42 are not performed as part of the method 10. Alternatively, the drying 44 could be performed after rinsing 40 the treated pulped fibers from the treating 36 of the washed pulped fibers with the pH adjustment solution, such as illustrated in the preferred embodiment depicted in FIG. 1. Drying 44 can be performed using either air-drying or providing heat and/or forced air, as is known in the art.

The method 10 can also include testing 46 the clean fibers after drying 44 for metal analysis and/or other contaminate analysis to ensure levels of components other than fibers are at desired levels.

Advantageously, the clean fibers from method 10 can be used to manufacture an article from recycled fibers. An article using recycled clean fibers from method 10 discussed herein can be manufactured in the same fashion as articles manufactured from original fibers via methods known in the art. The clean fibers from method 10 that are being recycled can form 100% of the fibers of the article, or a lesser percentage of the fibers of the article.

Small Scale Testing

Heavily contaminated wipers were tested to quantify the amounts and types of some of the contaminates in the wipers. The results of such testing analysis is shown below, in Table 1, with the regulatory level concentration being based on the Environmental Protection Agency Toxicity Characteristic Leaching Procedure (TCLP). As can be seen from Table 1, contaminated articles, such as industrial wipers, can have a wide range of contaminates and quantities of contaminates, leading to the difficulty in providing a solution that addresses each of the contaminates effectively. Additionally, heavily contaminated wipers likely will have contaminates forced into wiper's interior pores as well as fiber's lumen structures, making cleaning more difficult as opposed to lightly contaminated articles where the contaminates are likely largely on the exterior surface of the wiper.

TABLE 1 Regulatory Wiper Wiper Wiper Wiper Wiper Wiper Wiper Wiper Level 1 2 3 4 5 6 7 8 Contaminate (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) Oil & Grease 5 41.1 113.6 172.5 176.4 69.3 64.7 54.6 102.3 (HEM) Arsenic 5 0.001 6.42 7.57 1.65 0.001 0.001 0.001 0.001 Barium 100 2.61 92.4 108 32.3 8.9 8.97 8.06 11 Chromium 5 6.37 5.3 6.41 6.54 1.33 1.59 1.41 1.45 Lead 5 67.1 0.001 0.001 1.38 11.8 12.8 10.9 23.7

Testing was then conducted to clean heavily contaminated wipers using detergents and water alone, without the application of a magnetic field to the suspension of dissociated pulped fibers as discussed above in method 10 and as illustrated in FIG. 1. This testing confirmed that heavily contaminated articles cannot be sufficiently cleaned by detergents and water alone, as shown in Table 2 below. In both cases of cleaning with water and detergent, or just water alone, dark fibers, particles, and dots were visually apparent on the dried fibers.

TABLE 2 TCLP Contaminate Levels Regulatory Without Level Detergent With Detergent Contaminates (mg/L) (mg/L) SC A (mg/L) Oil & Grease 5 141.20 5.40 (HEM) Arsenic 5.0 3.91 0.00 Barium 100.0 60.93 3.26 Chromium 5.0 4.93 2.17 Lead 5.0 6.27 5.10

Table 3 below provides a summary of the removal efficacy of the method 10 involving where a magnetic field was applied during the washing 26 of the dissociated pulped fibers with in a solution including detergent in comparison to only washing the dissociated pulped fibers with a detergent. The column titled “Dirty Wiper” provides information of the contaminate levels in dirty wipers alone before method 10 was utilized. As shown in Table 3, applying a magnetic field while washing the dissociated pulped fibers provide enhanced removal of contaminates as compared to use of the detergent alone and the use of the detergent and a pH adjustment. Additionally, providing an temperature in the range of above 50° C. (e.g., about 65° C.) and preferably between 75° C. and 90° C. when washing 26 the dissociated pulped fibers utilizing the detergent and applying a magnetic field and providing an optimized pH level of about 2.0 of the pH adjustment solution and a temperature of about 65° C. when treating 36 the washed pulped fibers provided substantially enhanced results in removing contaminates from the wipers, with each of the contaminates listed in the table below being below 1.0 mg/L.

TABLE 3 Determined TCLP Contaminate Levels (mg/L) Magnet + SC A Detergent (optimized temp) + pH SC A Magnet + SC A adjustment SC A Detergent + Detergent + pH (optimized Detergent pH Contaminates Dirty Wiper adjustment temp) only adjustment Oil & Grease 99.31 4.00 0.733 5.40 1.77 (HEM) Arsenic 1.96 0.00 0.001 0.00 0.00 Barium 34.03 0.55 0.001 3.26 1.71 Chromium 3.80 0.00 0.001 2.17 1.69 Lead 15.96 1.10 0.001 5.10 2.47

EMBODIMENTS Embodiment 1

A method for cleaning fibers from a contaminated article, the method comprising: providing a contaminated article comprising contaminates and at least one of fibers and filaments; pulping the contaminated article to separate the at least one of fibers and filaments from the contaminated article in a first solution to provide dissociated pulped fibers; forming a suspension comprising the dissociated pulped fibers from the contaminated article and a detergent; applying a magnetic field to the suspension; mixing the suspension to wash the dissociated pulped fibers while applying the magnetic field to the suspension thereby forming washed pulped fibers; removing contaminates from the suspension; removing the washed pulped fibers from the suspension; rinsing the washed pulped fibers after removing the washed pulped fibers from the suspension to provide rinsed pulped fibers; and drying the rinsed pulped fibers to provide clean fibers.

Embodiment 2

The method of embodiment 1, wherein removing contaminates from the suspension comprises skimming a surface of the suspension as contaminates accumulate to the surface of the suspension.

Embodiment 3

The method of any one of the preceding embodiments, further comprising: pre-sorting and pre-washing the contaminated article prior to pulping the contaminated article, the pre-washing comprising stirring the contaminated article in a pre-washing solution.

Embodiment 4

The method of any one of the preceding embodiments, further comprising: treating the washed pulped fibers with a pH adjustment solution after removing the washed pulped fibers from the suspension to provide treated pulped fibers.

Embodiment 5

The method of embodiment 4, further comprising: neutralizing and rinsing the treated pulped fibers to provide rinsed pulped fibers.

Embodiment 6

The method of embodiment 4, wherein treating the pulped fibers with the pH adjustment solution comprises heating the pH adjustment solution to at least about 50° Celsius.

Embodiment 7

The method of embodiment 6, wherein pulping the contaminated article to separate the at least one of fibers and filaments from the contaminated article further comprises heating the first solution to at least about 50° Celsius.

Embodiment 8

The method of any one of the preceding embodiments, wherein pulping the contaminated article to separate the at least one of fibers and filaments from the contaminated article to provide dissociated pulped fibers occurs within a magnetic field.

Embodiment 9

The method of any one of the preceding embodiments, wherein forming the suspension comprises providing the dissociated pulped fibers and the detergent in a second solution, and wherein the magnetic field applied to the suspension is provided by at least one magnet, the at least one magnet being at least partially submerged in the suspension.

Embodiment 10

The method of any one of the preceding embodiments, wherein the contaminates are selected from the group consisting of oils, greases, solvents, adhesives, and lubricants.

Embodiment 11

The method of any one of the preceding embodiments, further comprising: filtering the dissociated pulped fibers from the first solution prior to forming the suspension with the dissociated pulped fibers and the detergent.

Embodiment 12

The method of embodiment 11, further comprising: rinsing the dissociated pulped fibers after filtering the dissociated pulped fibers from the first solution and prior to forming the suspension with the dissociated pulped fibers and the detergent.

Embodiment 13

The method of any one of the preceding embodiments, further comprising: cutting the contaminated article into a plurality of strips prior to pulping the contaminated article.

Embodiment 14

The method of any one of the preceding embodiments, wherein the contaminated article is a non-woven article.

Embodiment 15

The method of embodiment 14, wherein the non-woven article comprises pulp fibers and at least one of polymeric fibers and polymeric filaments.

Embodiment 16

The method of embodiment 14, wherein the non-woven article comprises pulp fibers and polymeric fibers, and wherein the ratio of pulp fibers to polymeric fibers is at least 0.5.

Embodiment 17

The method of any one of the preceding embodiments, wherein the magnetic field applied to the suspension has a strength of at least 5000 gauss.

Embodiment 18

The method of any one of the preceding embodiments, wherein a plurality of contaminated articles are cleaned simultaneously.

Embodiment 19

A method for manufacturing an article from recycled fibers, wherein the clean fibers from the method according to any one of the preceding embodiments are used in the manufacturing of the article.

Embodiment 20

A method for cleaning fibers from a contaminated article, the method comprising: providing a contaminated article comprising contaminates and at least one of fibers and filaments, the contaminates comprising at least one of oils, greases, solvents, and lubricants; pre-washing the contaminated article in a pre-washing solution; pulping the contaminated article in a first solution to separate the at least one of fibers and filaments from the contaminated article to provide dissociated pulped fibers; the first solution being heated; applying a magnetic field to the first solution while pulping the contaminated article to provide dissociated pulped fibers; filtering the dissociated pulped fibers from the first solution after pulping the contaminated article; rinsing the dissociated pulped fibers after filtering the pulped fibers from the first solution; forming a suspension comprising the dissociated pulped fibers from the contaminated article and a detergent in a second solution; applying a magnetic field to the second solution; mixing the suspension to wash the dissociated pulped fibers while applying the magnetic field to the suspension thereby forming washed pulped fibers; skimming the surface of the suspension to remove contaminates; rinsing the washed pulped fibers after removing the washed pulped fibers from the suspension to provide rinsed pulped fibers; treating the rinsed pulped fibers with a pH adjustment solution to provide treated pulped fibers, the pH adjustment solution being heated; rinsing the treated pulped fibers to provide further rinsed pulped fibers; and drying the further rinsed pulped fibers to provide clean fibers.

Embodiment 21

The method of embodiment 20 wherein an amount of the detergent is quantified as a weight ratio of the detergent actives to the contaminated article and is in a range of 0.0025 to 0.10 and more preferably in a range of 0.01 to 0.10.

Embodiment 22

The method of embodiment 21, wherein the detergent is added during the forming step and at least one of the pre-wash and mixing steps and a total amount of detergent added during all steps is in the range of 0.0025 to 0.10 and more preferably in the range of 0.010 to 0.10.

All documents cited in the Detailed Description are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this written document conflicts with any meaning or definition of the term in a document incorporated by references, the meaning or definition assigned to the term in this written document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. For example, one or more steps of the method 10 can be removed from the method 10, or adjusted in order, without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims

1. A method for cleaning fibers from a contaminated article, the method comprising:

providing a contaminated article comprising contaminates and at least one of fibers and filaments;

pulping the contaminated article to separate the at least one of fibers and filaments from the contaminated article in a first solution to provide dissociated pulped fibers;

forming a suspension comprising the dissociated pulped fibers from the contaminated article and a detergent;

applying a magnetic field to the suspension;

mixing the suspension to wash the dissociated pulped fibers while applying the magnetic field to the suspension thereby forming washed pulped fibers;

removing contaminates from the suspension;

removing the washed pulped fibers from the suspension;

rinsing the washed pulped fibers after removing the washed pulped fibers from the suspension to provide rinsed pulped fibers; and

drying the rinsed pulped fibers to provide clean fibers.

2. The method of claim 1, wherein removing contaminates from the suspension comprises skimming a surface of the suspension as contaminates accumulate to the surface of the suspension.

3. The method of claim 1, further comprising:

Pre-sorting and pre-washing the contaminated article prior to pulping the contaminated article, the pre-washing comprising stirring the contaminated article in a pre-washing solution.

4. The method of claim 1, further comprising:

treating the washed pulped fibers with a pH adjustment solution after removing the washed pulped fibers from the suspension to provide treated pulped fibers.

5. The method of claim 4, further comprising:

Neutralization and rinsing the treated pulped fibers to provide rinsed pulped fibers.

6. The method of claim 4, wherein treating the pulped fibers with the pH adjustment solution comprises heating the pH adjustment solution to at least about 50° Celsius.

7. The method of claim 6, wherein pulping the contaminated article to separate the at least one of fibers and filaments from the contaminated article further comprises heating the first solution to at least about 50° Celsius.

8. The method of claim 1, wherein pulping the contaminated article to separate the at least one of fibers and filaments from the contaminated article to provide dissociated pulped fibers occurs within a magnetic field.

9. The method of claim 1, wherein forming the suspension comprises providing the dissociated pulped fibers and the detergent in a second solution, and wherein the magnetic field applied to the suspension is provided by at least one magnet, the at least one magnet being at least partially submerged in the suspension.

10. The method of claim 1, wherein the contaminates are selected from the group consisting of oils, greases, solvents, and lubricants.

11. The method of claim 1, further comprising:

filtering the dissociated pulped fibers from the first solution prior to forming the suspension with the dissociated pulped fibers and the detergent.

12. The method of claim 11, further comprising:

rinsing the dissociated pulped fibers after filtering the dissociated pulped fibers from the first solution and prior to forming the suspension with the dissociated pulped fibers and the detergent.

13. The method of claim 1, further comprising:

cutting the contaminated article into a plurality of strips prior to pulping the contaminated article.

14. The method of claim 1, wherein the contaminated article is a non-woven article.

15. The method of claim 14, wherein the non-woven article comprises pulp fibers and at least one of polymeric fibers and polymeric filaments.

16. The method of claim 14, wherein the non-woven article comprises pulp fibers and polymeric fibers, and wherein the ratio of pulp fibers to polymeric fibers is at least 0.5.

17. The method of claim 1, wherein the magnetic field applied to the suspension has a strength of at least 5000 gauss.

18. The method of claim 1, wherein a plurality of contaminated articles are cleaned simultaneously.

19. A method for manufacturing an article from recycled fibers, wherein the clean fibers from the method according to claim 1 are used in the manufacturing of the article.

20. A method for cleaning fibers from a contaminated article, the method comprising:

providing a contaminated article comprising contaminates and at least one of fibers and filaments, the contaminates comprising at least one of oils, greases, solvents, and lubricants;

pre-sorting and pre-washing the contaminated article in a pre-washing solution;

pulping the contaminated article in a first solution to separate the at least one of fibers and filaments from the contaminated article to provide dissociated pulped fibers; the first solution being heated;

applying a magnetic field to the first solution while pulping the contaminated article to provide dissociated pulped fibers;

filtering the dissociated pulped fibers from the first solution after pulping the contaminated article;

rinsing the dissociated pulped fibers after filtering the pulped fibers from the first solution;

forming a suspension comprising the dissociated pulped fibers from the contaminated article and a detergent in a second solution;

applying a magnetic field to the second solution;

mixing the suspension to wash the dissociated pulped fibers while applying the magnetic field to the suspension thereby forming washed pulped fibers;

skimming the surface of the suspension to remove contaminates;

rinsing the washed pulped fibers after removing the washed pulped fibers from the suspension to provide rinsed pulped fibers;

treating the rinsed pulped fibers with a pH adjustment solution to provide treated pulped fibers, the pH adjustment solution being heated;

neutralizing and rinsing the treated pulped fibers to provide further rinsed pulped fibers; and

drying the further rinsed pulped fibers to provide clean fibers.

21. The method of claim 20 wherein an amount of the detergent is quantified as a weight ratio of the detergent to the contaminated article and is in a range of 0.0025 to 0.10 and more preferably in a range of 0.010 to 0.10.

22. The method of claim 21, wherein the detergent is added during the forming step and at least one of the pre-wash and mixing steps and a total amount of detergent added during all steps is in the range of 0.0025 to 0.10 and more preferably in the range of 0.010 to 0.10.