Methods of recycling carpet components and carpet components formed thereform

Information

  • Patent Grant
  • 8113448
  • Patent Number
    8,113,448
  • Date Filed
    Wednesday, April 22, 2009
    15 years ago
  • Date Issued
    Tuesday, February 14, 2012
    12 years ago
Abstract
Methods of recycling carpet components are disclosed. Usable compositions containing recycled carpet components, and carpets and carpet components containing recycled carpet components are also disclosed.
Description
TECHNICAL FIELD

The present invention relates to methods of recycling carpet components, usable compositions containing recycled carpet components, and new carpets and carpet components containing recycled carpet components.


BACKGROUND

Efforts continue to further develop ways to effectively and efficiently recycle carpet components.


SUMMARY

The present invention continues the effort to further develop ways to effectively and efficiently recycle carpet components by the discovery of methods of recycling carpet components previously destined for landfills. The methods of the present invention enable the formation of a free-flowing powder from a tacky first mixture of used carpet components. The resulting free-flowing powder has substantially no tackiness and is suitable for incorporation into new carpet components such as a new carpet backing or a new carpet adhesive component.


Accordingly, the present invention is directed to methods of recycling carpet components. In one exemplary embodiment, the method of recycling carpet components comprises separating at least a portion of fibers from a first mixture of carpet components comprising carpet fibers, a carpet adhesive component, and used filler material so as to form a second mixture comprising residual carpet fibers, the carpet adhesive component, and the used filler material; and co-grinding the second mixture with a solid inorganic particulate material, wherein said co-grinding step results in a third mixture comprising a free-flowing powder having an average particle size. Typically, the free-flowing powder has an average particle size of less than 50 microns (μm), and a particle size range of from about 1.0 μm to about 300 μm.


The present invention is further directed to the free-flowing powder resulting from the disclosed methods of recycling carpet components. In one exemplary embodiment, the free-flowing powder comprises (i) particles of recycled carpet material, the recycled carpet material comprising residual carpet fibers or carpet fiber portions, a carpet adhesive component, and used filler material; and (ii) solid inorganic particulate material, the solid inorganic particulate material being from a source other than recycled carpet material; wherein the free-flowing powder has a particle size ranging from about 1.0 to about 300 microns (μm). Typically, the free-flowing powder has an average particle size of less than 50 μm.


The present invention is even further directed to carpet components comprising the free-flowing powder resulting from the disclosed methods of recycling carpet components. In one exemplary embodiment, the carpet component comprises free-flowing powder, wherein the free-flowing powder comprises (i) particles of recycled carpet material, the recycled carpet material comprising residual carpet fibers or carpet fiber portions, a carpet adhesive component, and used filler material; and (ii) solid inorganic particulate material, the solid inorganic particulate material being from a source other than recycled carpet material; wherein the free-flowing powder has a particle size ranging from about 1.0 to about 300 microns (μm). The carpet component may further comprise one or more additional components such as a polymeric matrix material, a latex component, carpet fibers, or any combination thereof.


These and other features and advantages of the present invention will become apparent after a review of the following detailed description of the disclosed embodiments and the appended claims.





BRIEF DESCRIPTION OF THE FIGURE

The present invention is further described with reference to the appended FIGURE, wherein:



FIG. 1 depicts a flow diagram of an exemplary method of recycling carpet components according to the present invention.





DETAILED DESCRIPTION

To promote an understanding of the principles of the present invention, descriptions of specific embodiments of the invention follow and specific language is used to describe the specific embodiments. It will nevertheless be understood that no limitation of the scope of the invention is intended by the use of specific language. Alterations, further modifications, and such further applications of the principles of the present invention discussed are contemplated as would normally occur to one ordinarily skilled in the art to which the invention pertains.


The present invention is directed to methods of recycling carpet components. The present invention is further directed to the free-flowing powder resulting from the disclosed methods of recycling carpet components. The present invention is even further directed to carpet components comprising the free-flowing powder resulting from the disclosed methods of recycling carpet components.


In one exemplary embodiment, the method of recycling carpet components comprises separating at least a portion of fibers from a first mixture of carpet components comprising carpet fibers, a carpet adhesive component, and used filler material so as to form a second mixture comprising residual carpet fibers, the carpet adhesive component, and the used filler material; and co-grinding the second mixture with a solid inorganic particulate material, wherein said co-grinding step results in a third mixture comprising a free-flowing powder having an average particle size. An exemplary first mixture of carpet components comprises from about 40 to about 60 wt % of the carpet fibers; from about 5.0 to about 20 wt % of the adhesive component; and from about 15 to about 40 wt % of the used filler material; wherein all weight percentages are based on a total weight of the first mixture.


Prior to processing, the first mixture comprises a tacky, conglomerating mixture that alone is incapable of being ground into a free-flowing powder due to the tackiness of the carpet adhesive component (e.g., a latex binder) within the first mixture. The method of the present invention enables the tacky first mixture to be converted into a free-flowing powder by separating at least a portion of fibers from the first mixture, and co-grinding solid inorganic particulate material with the tacky second mixture (i.e., the first mixture minus a portion of carpet fibers within the first mixture). The co-grinding step results in a free-flowing powder, wherein at least a portion of the free-flowing powder comprises particles comprising (i) a portion of the carpet adhesive component at least partially surrounded by (ii) a portion of the solid inorganic particulate material.


The separating step may comprise any separation step that removes at least a portion of carpet fibers from the tacky first mixture. Suitable separation steps include, but are not limited to, one or more screening steps, one or more gravity separation steps, one or more air classification steps, or any combination thereof. In some desired embodiments, the separation step comprises processing the first mixture through one or more screening steps utilizing, for example, one or more screens having a screen mesh size ranging from about 10 to about 80 mesh (e.g., a sieve opening size of from about 0.18 to about 2.0 millimeters (mm)).


In the co-grinding step, an effective amount of solid inorganic particulate material is co-ground with the second mixture in order to form a free-flowing powder. The co-grinding step may comprise processing the second mixture through one or more grinding mills such as one or more hammer mills, one or more ball mills, one or more roller mills, or any combination thereof.


Typically, solid inorganic particulate material is added to the second mixture so as to form a third mixture, wherein the third mixture comprises from about 10 to about 90 weight percent (wt %) of the second mixture, and from about 90 to about 10 weight percent (wt %) of the solid inorganic particulate material. In more desired embodiments, solid inorganic particulate material is added to the second mixture so as to form a third mixture, wherein the third mixture comprises from about 20 to about 80 weight percent (wt %) of the second mixture, and from about 80 to about 20 weight percent (wt %) of the solid inorganic particulate material.


Suitable solid inorganic particulate material for use in the present invention includes, but is not limited to, (i) new filler material selected from calcium carbonate, limestone, alumina trihydrate, brucite (i.e., magnesium hydroxide), feldspar, dolomite, silica, clay, or any combination thereof; (ii) post industrial filler material selected from fly ash, glass (e.g., e-glass), and any combination thereof; (iii) post consumer filler material comprising post consumer glass, recycled paper, and any combination thereof; or (iv) any combination of any of (i), (ii) and (iii). In some exemplary embodiments, the solid inorganic particulate material comprises calcium carbonate and/or limestone. In some exemplary embodiments, the solid inorganic particulate material comprises post consumer glass (e.g., ground glass) from post consumer glass sources such as beverage containers, vehicle windshields, fluorescent lights, other post consumer glass containers (e.g., jars), or any combination thereof.


In place of or in addition to the co-grinding step, any one or combination of the above-mentioned solid inorganic particulate materials may be added to the second mixture so as to form the third mixture. For example, any one or combination of the above-mentioned solid inorganic particulate materials may be simply added to and blended with the second mixture to form the third mixture. In other embodiments, any one or combination of the above-mentioned solid inorganic particulate materials may be added to and co-grinded with the second mixture to form the third mixture. In other embodiments, a first portion of any one or combination of the above-mentioned solid inorganic particulate materials may be added to and co-grinded with the second mixture, and a second portion of any one or combination of the above-mentioned solid inorganic particulate materials may be added to and blended with the resulting co-ground composition to form the third mixture.


The resulting free-flowing powder typically has an average particle size that ranges from about 1.0 to about 50 microns (μm) (or from about 1.0 to about 40 μm, or from about 1.0 to about 30 μm). Further, the resulting free-flowing powder typically has a particle size ranging from about 1.0 to about 300 microns (μm) (or from about 1.0 to about 250 μm, or from about 1.0 to about 200 μm, or from about 1.0 to about 150 μm, or from about 1.0 to about 100 μm, or from about 1.0 to about 50 μm).


An exemplary method of recycling carpet components according to the present invention is depicted in FIG. 1. As shown in FIG. 1, exemplary method of recycling 100 comprises start 10 followed by step 15, wherein used carpet and/or carpet components are provided for recycling. From step 15, exemplary method 100 proceeds to step 20, wherein used carpet and/or carpet components are shredded to form a first mixture. From step 20, exemplary method 100 proceeds to first separation step 25, wherein a portion of carpet fibers are separated from and removed from the first mixture to form a second mixture.


The removed carpet fibers are shown in box 30 of exemplary method 100. It should be noted that the removed carpet fibers are potentially reusable fibers for carpet applications or other possible uses. Typically, from about 40 to about 60 wt % of the first mixture is recovered as potentially reusable fibers, while about 60 to about 40 wt % of the first mixture remains as the second mixture.


As shown in FIG. 1, from step 20, exemplary method 100 proceeds to second separation step 35, wherein additional residual fibers and a portion of the adhesive material is separated from and removed from the second mixture. The removed additional residual fibers and portion of the adhesive material are shown in box 40 of exemplary method 100. Typically, from about 1.0 to about 30 wt % of the second mixture is removed during step 35 in the form of additional residual fibers and a portion of adhesive material, for example, any adhesive material having a particle size greater than about 4.7 millimeters (mm) (i.e., using a 4 mesh screen). The remaining 99 to 70 wt % of the second mixture proceeds to step 45 of exemplary method 100.


It should be noted that second separation step 35 is not necessary in all embodiments of the present invention. In other words, second separation step 35 is an optional step in some of the methods of the present invention.


In step 45, the second mixture is exposed to heat and/or radiation to truncate the residual fibers and/or kill any bacteria/fungi (collectively referred to as “microorganisms”) present in the second mixture. Typically, when exposed, the second mixture is exposed to a temperature of from about 100 to about 250° C. or UV light for a time period ranging from about 20 to about 200 seconds.


It should be noted that exposure step 45 is not necessary in all embodiments of the present invention. In other words, exposure step 45 is an optional step in some of the methods of the present invention.


As shown in FIG. 1, from optional exposure step 45, exemplary method 100 proceeds to step 50, wherein solid particulate material is added to the second mixture. Any of the above-mentioned solid particulate materials may be added to the second mixture at this time. It should be noted that other optional components may also be added to the second mixture during this step (or during a subsequent addition step (not shown)). Other optional components that may also be added to the second mixture include, but are not limited to, a biocide, organic flow agents (e.g., propylene or ethylene glycol or triethanolamine), or any combination thereof.


From step 55, exemplary method 100 proceeds to step 55, wherein the second mixture, solid particulate material, and any other optional components are co-ground with one another to produce a third mixture comprising a free-flowing powder having a desired particle size. As noted above, typically, the resulting free-flowing powder has an average particle size of less than 50 μm. In some embodiments, the resulting free-flowing powder has an average particle size ranging from about 15 to about 40 μm. In other embodiments, the resulting free-flowing powder has an average particle size ranging from about 5 to about 30 μm.


In some embodiments, the resulting free-flowing powder contains greater than 10 wt % of post consumer content (e.g., post consumer glass, recycled paper, etc.). Desirably, the resulting free-flowing powder contains from about 10 to about 90 wt % of post consumer content.


It should be understood that steps 50 and 55 may occur substantially simultaneously. In other words, the second mixture, solid particulate material and any other optional components may be simultaneously added, from one or more sources, directly into a co-grinding apparatus as oppose to mixing/blending prior to advancing to the co-grinding apparatus.


As shown in FIG. 1, from step 55, exemplary method 100 proceeds to stop box 60. Although not shown in FIG. 1, exemplary methods of recycling carpet and/or carpet components, such as exemplary method 100, may further comprise additional process steps as discussed herein.


The methods of recycling carpet components in accordance with the present invention may further comprise incorporating the free-flowing powder into a new carpet component. For example, the free-flowing powder may be incorporated into a new carpet backing, a new carpet adhesive component, a polyethylene, a polyvinyl chloride, a plastisol, a urethane, a SBR (i.e., styrene-butadiene rubber) latex, a vinyl acetate latex, or any combination thereof. Further, the methods of recycling carpet components in accordance with the present invention may further comprise one or more additional method steps including, but not limited to, offering for sale the free-flowing powder, and offering for sale a new carpet component comprising the free-flowing powder.


The present invention is further directed to the free-flowing powder resulting from the disclosed methods of recycling carpet components. Typically, the free-flowing powder comprises (i) particles of recycled carpet material, the recycled carpet material comprising residual carpet fibers or carpet fiber portions, a carpet adhesive component, and used filler material; and (ii) solid inorganic particulate material, the solid inorganic particulate material being from a source other than recycled carpet material; wherein the free-flowing powder has an average particle size ranging from about 1.0 to about 50 microns (μm) (or from about 1.0 to about 40 μm, or from about 1.0 to about 30 μm), and a particle size ranging from about 1.0 to about 300 microns (μm) (or from about 1.0 to about 250 μm, or from about 1.0 to about 200 μm, or from about 1.0 to about 150 μm, or from about 1.0 to about 100 μm, or from about 1.0 to about 50 μm). As discussed above, typically, at least a portion of the free-flowing powder comprises particles comprising (i) a portion of the carpet adhesive component at least partially surrounded by (ii) a portion of the solid inorganic particulate material.


Further, as discussed above, the free-flowing powder resulting from the disclosed methods of recycling carpet components comprises from about 10 to about 90 weight percent (wt %) of the second mixture (i.e., recycled carpet components), and from about 90 to about 10 weight percent (wt %) of the solid inorganic particulate material (e.g., post consumer filler material). In more desired embodiments, the free-flowing powder resulting from the disclosed methods of recycling carpet components comprises from about 20 to about 80 wt % of the second mixture (i.e., recycled carpet components), and from about 80 to about 20 wt % of the solid inorganic particulate material (e.g., post consumer filler material).


The present invention is even further directed to new carpet components comprising the free-flowing powder resulting from the disclosed methods of recycling carpet components. In one exemplary embodiment, the new carpet component comprises free-flowing powder, wherein the free-flowing powder comprises (i) particles of recycled carpet material, the recycled carpet material comprising residual carpet fibers or carpet fiber portions, a carpet adhesive component, and used filler material; and (ii) solid inorganic particulate material, the solid inorganic particulate material being from a source other than recycled carpet material. As discussed above, the free-flowing powder within the new carpet component has an average particle size ranging from about 1.0 to about 50 microns (μm) (or from about 1.0 to about 40 μm, or from about 1.0 to about 30 μm), and a particle size ranging from about 1.0 to about 300 microns (μm) (or from about 1.0 to about 250 μm, or from about 1.0 to about 200 μm, or from about 1.0 to about 150 μm, or from about 1.0 to about 100 μm, or from about 1.0 to about 50 μm).


The new carpet component desirably comprises at least about 10 wt % of post consumer filler material, such as the exemplary post consumer filler material described above. In some embodiments, the new carpet component comprises at least about 12 wt % (or at least about 14 wt %, or at least about 16 wt %, or at least about 18 wt %, or at least about 20 wt %, or greater than about 20 wt %) of post consumer filler material, such as the exemplary post consumer filler material described above, in combination with the second mixture as described above. Suitable new carpet components include, but are not limited to, a new carpet backing, a new carpet adhesive component, and/or any other material used to form a new carpet component.


While the specification has been described in detail with respect to specific embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing, may readily conceive of alterations to, variations of, and equivalents to these embodiments. Accordingly, the scope of the present invention should be assessed as that of the appended claims and any equivalents thereto.

Claims
  • 1. A method of recycling carpet components, said method comprising: separating at least a portion of fibers from a first mixture of carpet components comprising carpet fibers, a carpet adhesive component, and used filler material so as to form a second mixture comprising residual carpet fibers, the carpet adhesive component, and the used filler material; andco-grinding the second mixture with a solid inorganic particulate material, wherein said co-grinding step results in a third mixture comprising a free-flowing powder having an average particle size.
  • 2. The method of claim 1, wherein at least a portion of the free-flowing powder comprises particles comprising (i) a portion of the carpet adhesive component at least partially surrounded by (ii) a portion of the solid inorganic particulate material.
  • 3. The method of claim 1, wherein the average particle size of the third mixture ranges from about 1.0 to about 50 microns (μm).
  • 4. The method of claim 1, wherein the third mixture comprises particles having a particle size ranging from about 1.0 to about 300 microns (μm).
  • 5. The method of claim 1, wherein the third mixture comprises from about 10 to about 90 weight percent (wt %) of the second mixture, and from about 90 to about 10 weight percent (wt %) of the solid inorganic particulate material.
  • 6. The method of claim 1, wherein the third mixture comprises from about 20 to about 80 weight percent (wt %) of the second mixture, and from about 80 to about 20 weight percent (wt %) of the solid inorganic particulate material.
  • 7. The method of claim 1, wherein the solid inorganic particulate material comprises (i) new filler material selected from calcium carbonate, limestone, alumina trihydrate, brucite, feldspar, dolomite, silica, or any combination thereof; (ii) post industrial filler material selected from fly ash, glass, and any combination thereof; (iii) post consumer filler material comprising post consumer glass; or (iv) any combination of any of (i), (ii) and (iii).
  • 8. The method of claim 7, wherein the solid inorganic particulate material comprises calcium carbonate, limestone, or a combination thereof.
  • 9. The method of claim 7, wherein the solid inorganic particulate material comprises post consumer glass.
  • 10. The method of claim 1, wherein said separating step comprises: processing the first mixture through one or more screens having a screen mesh size ranging from about 10 to about 80 mesh.
  • 11. The method of claim 1, wherein said co-grinding step comprises: processing the second mixture and the solid inorganic particulate material through one or more grinding mills.
  • 12. The method of claim 1, wherein the first mixture comprises: from about 40 to about 60 wt % of the carpet fibers;from about 5 to about 20 wt % of the adhesive component; andfrom about 15 to about 40 wt % of the used filler material;wherein all weight percentages are based on a total weight of the first mixture.
  • 13. The method of claim 1, further comprising: incorporating the free-flowing powder into a new carpet component.
  • 14. The method of claim 13, wherein the new carpet component comprises a new carpet backing, a new carpet adhesive component, or a combination thereof.
  • 15. The method of claim 1, further comprising: offering for sale the free-flowing powder.
US Referenced Citations (108)
Number Name Date Kind
4028159 Norris Jun 1977 A
4103519 Davidson Aug 1978 A
4106896 Norris et al. Aug 1978 A
4270283 Ellis Jun 1981 A
4282705 Fontan Aug 1981 A
4418433 Moreland et al. Dec 1983 A
4586208 Trevarthen May 1986 A
4637942 Tomarin Jan 1987 A
4700719 Sheahan Oct 1987 A
4730432 Schafer et al. Mar 1988 A
5033747 Young Jul 1991 A
5080112 Brackmanne et al. Jan 1992 A
5169870 Corbin et al. Dec 1992 A
5185380 Dressel et al. Feb 1993 A
5191692 Paione Mar 1993 A
5240530 Fink Aug 1993 A
5359061 Evans et al. Oct 1994 A
5433761 Teague et al. Jul 1995 A
5433769 Teague et al. Jul 1995 A
5456872 Ahrweiler Oct 1995 A
5457197 Sifniades et al. Oct 1995 A
5472763 Schwarz et al. Dec 1995 A
5494723 Erren et al. Feb 1996 A
5497979 Sharer Mar 1996 A
5500980 Morrow et al. Mar 1996 A
5518188 Sharer May 1996 A
5525153 Cosola Jun 1996 A
5538776 Corbin et al. Jul 1996 A
5578357 Fink Nov 1996 A
5598980 Dilly-Louis et al. Feb 1997 A
5604009 Long et al. Feb 1997 A
5656757 Jenczewski et al. Aug 1997 A
5681952 Sifniades et al. Oct 1997 A
5684052 Krishnan et al. Nov 1997 A
5704104 Bacon et al. Jan 1998 A
5719198 Young et al. Feb 1998 A
5724783 Mandish Mar 1998 A
5725926 Wang Mar 1998 A
5728444 Fink Mar 1998 A
5728741 Zegler et al. Mar 1998 A
5770632 Sekhar et al. Jun 1998 A
5859071 Young et al. Jan 1999 A
5876827 Fink et al. Mar 1999 A
5891198 Pearlstein Apr 1999 A
5895611 Geltinger et al. Apr 1999 A
5908701 Jennings et al. Jun 1999 A
5914353 Grizzler et al. Jun 1999 A
5916410 Moens Jun 1999 A
5929234 Sifniades et al. Jul 1999 A
5943829 Wilson Aug 1999 A
5977193 Corbin et al. Nov 1999 A
6020486 Booij et al. Feb 2000 A
6029916 White Feb 2000 A
6036726 Yang et al. Mar 2000 A
6039903 Kent et al. Mar 2000 A
6051300 Fink Apr 2000 A
6059207 Costello et al. May 2000 A
6111099 Frentzen et al. Aug 2000 A
6155020 Deem Dec 2000 A
6182913 Howe et al. Feb 2001 B1
6196435 Wu Mar 2001 B1
6211275 Xanthos et al. Apr 2001 B1
6241168 Young et al. Jun 2001 B1
6250575 White Jun 2001 B1
6271270 Muzzy et al. Aug 2001 B1
6274637 Schallenberg Aug 2001 B1
6291048 Jerdee et al. Sep 2001 B1
6299691 Pelzer Oct 2001 B1
6316075 Desai et al. Nov 2001 B1
6332253 Rasnick, Jr. et al. Dec 2001 B1
6341462 Kiik et al. Jan 2002 B2
6379489 Goulet et al. Apr 2002 B1
6387967 Muzzy et al. May 2002 B2
6392037 Agterberg et al. May 2002 B1
6524653 Jones Feb 2003 B1
6562119 Jones, IV et al. May 2003 B2
6582816 Rasnick, Jr. et al. Jun 2003 B2
6610769 Blahpain et al. Aug 2003 B1
6682671 Howell et al. Jan 2004 B1
6756412 Muzzy Jun 2004 B2
6763637 Pelosi, Jr. Jul 2004 B2
6786988 Bell Sep 2004 B1
6814826 Bell Nov 2004 B1
6828372 Sullivan et al. Dec 2004 B2
6860953 Grizzle et al. Mar 2005 B1
6936201 Desai et al. Aug 2005 B2
6945007 Kobayashi et al. Sep 2005 B2
6953119 Wening Oct 2005 B1
6990703 Brown et al. Jan 2006 B2
7045590 Bell May 2006 B2
7064092 Hutchison et al. Jun 2006 B2
7066532 Schoemann Jun 2006 B2
7097723 Allison et al. Aug 2006 B2
7105069 Allison et al. Sep 2006 B2
7129347 Kampf et al. Oct 2006 B2
7160599 Hartman Jan 2007 B2
7235293 Dailey Jun 2007 B2
7244333 Hutchison et al. Jul 2007 B2
7252691 Philipson Aug 2007 B2
7272870 Pierce et al. Sep 2007 B2
7279065 Ogle et al. Oct 2007 B1
7338698 Bieser et al. Mar 2008 B1
7351465 Jerder et al. Apr 2008 B2
7357971 Bieser et al. Apr 2008 B2
7361401 Desai Apr 2008 B2
7419058 Wening Sep 2008 B2
7517426 Mano et al. Apr 2009 B2
20060134374 Bell et al. Jun 2006 A1
Related Publications (1)
Number Date Country
20100272995 A1 Oct 2010 US