Recycling carpets How to recycle carpets with PP/PA/PET/PE yarn and different backings?

Here’s a step-by-step example roadmap for turning UK most used carpet, a polypropylene-yarn, styrene-butadiene (SB)-backed carpet into reusable materials:

1. Collection & Pre-sorting • Gather post-consumer or post-industrial carpet rolls by type (broadloom vs. tile) and brand. • Visually inspect for non-carpet contaminants (tapes, adhesives, edge binding). Remove by hand.
2. Size Reduction • Shred the carpet into ~20–50 mm chips. This exposes both PP fibers and the SB-backing matrix. • A good shredder or granulator drastically improves downstream separation yields.
3. Fiber/Backing Separation A. Density‐based (float-sink) separation – PP has a density ≈0.90–0.92 g/cm³; SB latex (plus fillers) sits around 1.1–1.3 g/cm³. – In water or salt baths, PP fibers float while backing fragments sink. Skim off fibers and decant binder. B. Dissolution methods – Use mild alkaline or low-VOC solvents to dissolve the SB binder without attacking PP. – Rinse fibers, recover dissolved latex via precipitation, then wash and dry both streams. C. Emerging VAE-techniques – Some systems replace SB with VAE copolymers to allow “designed for disassembly,” so fibers, fillers, and binders part cleanly during recycling.
4. Recycling the PP Yarn • Mechanical recycling – Wash, dry, then melt-extrude into pellets. These grades suit injection molding, fibers for geotextiles or non-wovens. • Chemical recycling (pyrolysis or depolymerization) – Break PP down to monomers (propylene) or to mixed hydrocarbon oils, usable as feedstock or fuels. • Applications – Injection-molded crates, automotive parts, new synthetic fibers, even recycled carpet backing compounds.
5. Handling the SB Latex Backing • Energy recovery – Pyrolyze shredded backing to yield synthesis gas (syngas) and oils—powering boilers or making chemicals. • Asphalt modification – Pulverized SB-rich crumbs can be blended into bitumen to improve road-paving properties. • New binder production – Recover and re-emulsify latex solids to partially replace virgin SB in non-critical coatings and adhesives.
6. Downcycling as Composite Fillers • Mixed-waste streams that can’t be fully separated still serve as filler in products like rubber mats, underlayments, or cement-based building blocks.
7. Closed-Loop & Take-Back • Partner with a carpet take-back scheme (e.g., Ege’s CircleBack), where manufacturers commit to 98–100 % material recovery and reuse. • Specify monomaterial carpets from the outset—swap SB for more separation-friendly binders (VAE) and design fiber backing interfaces for easy delamination.
8. Policy & Economic Incentives • Leverage Extended Producer Responsibility (EPR) laws to share recycling costs. • Seek grants or green-premium offtake agreements for recycled PP to improve ROI.

— Next steps you might explore: chemical routes to break down SB into styrene and butadiene monomers; tailor float-sink baths for greater separation efficiency; or pilot “hot-melt” carpet backings that eliminate latex altogether.

Carpet basics

To understand the challenges is carpet recycling, one should understand it’s basics.

Carpet is can be woven or tufted. Most EU carpets are tufted.

There are carpet tiles and carpet broadloom. Carpet broadloom is the largest volume and most challenging to recycle. Because of price reason, there are many different compositions broadloom carpets.

Most carpets are backed with SB polymer. This polymer is in general crosslinking. And crossllinked polymers are hard to recycle, because

• 1. It is hard to seperate carpets
• 2. Crosslinked polymers are hard to re-use

Yarns

There are different yarns used.

Durability vs. Cost Comparison

Key Insights

• Nylon (PA) is the most durable but also the most expensive.
• Polypropylene (PP) is cost-effective but less resilient.
• Polyethylene (PE) is soft but lacks durability.
• Polyester (PET) offers a balance between cost and durability, making it popular for residential carpets.

Carpet Backing

Carpet backing technologies vary depending on the desired durability, comfort, and environmental impact. Some common technologies include:

• Primary and Secondary Backing: Primary backing provides structural support for the carpet fibers, while secondary backing enhances stability and durability.
  • Primary backing is often done with SB. Alternatives are VAE, PVB and secondary dispersions like Polyolefin and PET
• Polyurethane Foam Backing: Offers softness, insulation, and sound absorption, making it ideal for residential carpets.
• Rubber Backing: Used in commercial and industrial carpets, providing slip resistance and durability.
• Bitumen-Based Backing: Common in heavy-duty applications, offering moisture resistance and dimensional stability.
• Cushion Backing: Enhances comfort and acoustic performance, often used in office and hospitality settings.
• Eco-Friendly Backing: Includes recycled materials like polypropylene or polyester, reducing environmental impact.

What are current recycling flows

1. Post-Consumer Recycling: Carpets removed from homes and businesses are collected, sorted, and processed into new fibers, backing materials, or alternative products. However, a significant portion still goes to energy recovery rather than full recycling.
2. Post-Industrial Recycling: Manufacturers recycle production waste, such as fiber scraps and backing materials, into new carpet components or other industrial applications.
3. Carpet Tile Reuse: Some companies focus on reusing carpet tiles, assessing their condition and cleaning them for second-life applications in social housing or commercial spaces.
4. Material Separation & Fiber Recovery: Advanced technologies allow for fiber extraction, contaminant reduction, and purification, increasing the potential for high-value recycled materials.
5. Closed-Loop Recycling Initiatives: Industry-wide efforts aim to design carpets for recyclability, ensuring materials can be efficiently recovered and reused

Is there an easy solution?

Maybe, VAE offers the easiest solution in these complicated cases. If only the yarn’s can be seperated and clean offered to it’s basics industry, PA, PP, PE or PET, the yarns can profit from existing large recycling capacity in the plastics and textile industry. There are projects where VAE backed carpets are recycled bij a solvent solution process, of wich the outcome is that all used materials are seperated with low energy costs and high purity. In short:

• VAE has already a significant position in carpet tiles and carpet broadloom as VAE backing. The commercial use is already proven to be economic, withouth the recycling proposal
• VAE can be used with all kinds of yars
• VAE can be used in excisting productions lines, where mostly SB is used
• VAE can be dissolved, where carpet components can be cleanly seperated.

Most succesfull textile and plastic recycling methods today

Textile and plastic recycling have advanced significantly, with several successful methods leading the way in sustainability.

Textile Recycling Methods

1. Mechanical Recycling – Textiles are shredded into fibers and re-spun into yarns or used for insulation.
2. Chemical Recycling – Synthetic fibers like polyester are broken down into their base molecules for reuse.
3. Enzymatic Recycling – Specialized enzymes break down synthetic textiles into reusable materials.
4. AI-Assisted Sorting – Artificial intelligence improves textile waste separation for more efficient recycling.
5. Upcycling – Old textiles are repurposed into new fashion items or home decor.

Plastic Recycling Methods

1. Chemical Recycling (Depolymerization) – Converts plastics back into virgin-quality materials.
2. Enzymatic Recycling – Uses plastic-eating enzymes to break down PET and nylon.
3. Advanced Pyrolysis – Converts plastic waste into synthetic fuels.
4. Solvent-Based Recycling – Dissolves plastics to remove contaminants and recover high-quality material.
5. Microbial Decomposition – Bacteria and fungi naturally degrade plastics into harmless byproducts

Artificial grass recycling

Maybe, artificial grass is easier to recycle, because the difference in qualities is less, and already a lot of “monomaterial” grass is used and in further development.

Artificial grass recycling involves separating and processing its components to create new, reusable materials. Some key methods today include:

• Mechanical Recycling: The turf is shredded, and the fibers are separated from the backing. The plastic fibers can be reused in new turf, insulation, or plastic products.
• Chemical Recycling: Some facilities use chemical treatments to break down artificial grass into its base polymers, which can be repurposed into new synthetic materials.
• Infill Recovery: The sand and rubber infill used in artificial turf can be cleaned and reused in new sports fields or construction applications.
• Closed-Loop Recycling: Companies like GBN AGR have developed 100% circular recycling processes, ensuring that old turf is fully repurposed into high-quality raw materials