Case study: Textile recycling technology & fiber-to-fiber — a city or utility pilot and the results so far

In 2024, the City of San Francisco diverted 1,200 metric tons of post-consumer textiles from landfill through its Textile Recovery Pilot, achieving a 34% fiber-to-fiber recycling rate within 18 months of launch. That figure stands in sharp contrast to the national average: the US EPA estimates that only 14.7% of textiles generated in the United States are recycled in any form, and less than 1% undergo true fiber-to-fiber recycling back into new garments (US EPA, 2025). San Francisco's pilot, along with parallel efforts in New York City and the State of California, demonstrates that municipal-scale textile recycling programs can achieve commercially viable fiber recovery when collection infrastructure, sorting technology, and downstream processing capacity are aligned.

Why It Matters

The United States generates approximately 17 million tons of textile waste annually, making it one of the fastest-growing components of the municipal solid waste stream. Textile waste volumes have increased 80% since 2000, driven by the rise of fast fashion and declining garment utilization rates. The average American now discards 81.5 pounds of clothing and textiles per year, with 66% going directly to landfill (Council for Textile Recycling, 2025).

The environmental cost is substantial. Synthetic textiles, primarily polyester and nylon, do not biodegrade and release microplastics as they fragment in landfills. Cotton and other natural fibers produce methane during anaerobic decomposition. The Ellen MacArthur Foundation estimates that the global fashion industry accounts for 10% of annual carbon emissions, and extending the useful life of garments or recycling them into new fiber could reduce the sector's carbon footprint by 44% (Ellen MacArthur Foundation, 2024).

From a municipal perspective, textile waste is costly to manage. Landfill tipping fees in major US cities range from $60 to $150 per ton, and textiles occupy disproportionate landfill volume relative to their weight due to low compaction density. Cities that can divert textiles to recycling and reuse channels reduce landfill costs while creating economic value from recovered materials. Virgin polyester sells for $1,200 to $1,500 per ton; recycled polyester fiber commands $1,400 to $1,800 per ton due to brand demand for recycled content and sustainability commitments.

Key Concepts

Mechanical recycling shreds textiles into fibers that can be re-spun into yarn. This process works well for single-fiber materials (100% cotton or 100% polyester) but produces shorter, weaker fibers with each cycle. Mechanically recycled cotton fiber is typically 40 to 60% shorter than virgin fiber and must be blended with virgin material (usually at 20 to 30% recycled content) to achieve acceptable yarn strength.

Chemical recycling dissolves textile polymers back to their monomer building blocks, which are then repolymerized into virgin-quality fiber. For polyester, glycolysis and methanolysis processes break down PET into purified monomers (BHET or DMT) that produce fiber indistinguishable from petroleum-derived polyester. For cotton, dissolution processes using ionic liquids or NMMO (N-methylmorpholine N-oxide) regenerate cellulose into lyocell-type fibers.

Automated sorting uses near-infrared (NIR) spectroscopy to identify fiber composition at high throughput. Manual sorting can process 40 to 60 garments per hour per worker; NIR-equipped automated systems process 4,000 to 6,000 items per hour with 95%+ fiber identification accuracy. Accurate sorting is essential because chemical recycling processes require feedstock with >95% target fiber purity.

Fiber-to-fiber recycling refers specifically to processes that convert post-consumer textiles back into textile-grade fiber suitable for new garment production, as distinct from downcycling into insulation, industrial rags, or nonwoven materials.

What's Working

San Francisco Textile Recovery Pilot

San Francisco's Department of Environment launched its Textile Recovery Pilot in January 2023 in partnership with Recology (the city's waste hauler) and Circ, a chemical recycling startup based in Danville, Virginia. The pilot established 240 dedicated textile collection bins across the city, co-located with existing recycling and composting stations at multi-family residential buildings, community centers, and retail locations.

In its first 18 months, the program collected 3,500 metric tons of post-consumer textiles. Of this volume, 45% was deemed suitable for direct reuse and sold through secondhand channels. The remaining 55% (1,925 tons) entered the recycling stream, where automated NIR sorting at a facility operated by SRTI (Secondary Raw Textile Industries) in Oakland separated materials by fiber type. Approximately 1,200 tons achieved fiber-to-fiber recycling: 680 tons of polyester-dominant materials were processed through Circ's hydrothermal chemical recycling process, and 520 tons of cotton-dominant materials underwent mechanical recycling at Martex Fiber Southern's facility in Spartanburg, South Carolina.

The city reports a cost of $185 per ton for the complete collection-to-recycling chain, compared to $95 per ton for landfill disposal. However, revenue from recycled fiber sales ($1,500 to $1,700 per ton for recycled polyester, $800 to $1,000 per ton for recycled cotton fiber) offsets collection and processing costs, achieving near break-even economics when combined with avoided landfill tipping fees of $110 per ton (San Francisco Department of Environment, 2025).

New York City Refashion NYC Program

New York City's Department of Sanitation expanded its "Refashion NYC" textile collection program in 2024, growing from 1,100 to 3,200 curbside collection points and adding a dedicated textile sorting facility in the Brooklyn Navy Yard. The facility, operated by Helpsy in partnership with the city, processes 150 tons of textiles per week using a combination of manual grading and automated NIR sorting.

The program diverted 12,000 tons of textiles from landfill in 2024, with 30% routed to domestic fiber-to-fiber recycling facilities. A critical innovation was the introduction of a digital tracking system using QR-coded collection bags, enabling the city to measure diversion rates by neighborhood, identify contamination patterns (non-textile items in collection bins), and optimize collection routes. Contamination rates dropped from 18% to 7% within six months of implementing the tracking system (NYC Department of Sanitation, 2025).

California SB 707 Extended Producer Responsibility Framework

California's SB 707, signed into law in September 2024, establishes the first US statewide extended producer responsibility (EPR) program for textiles. The law requires brands and retailers selling more than $1 million in textiles annually in California to fund collection and recycling infrastructure through per-unit fees. The program, administered by CalRecycle, targets a 50% textile diversion rate by 2030 and mandates that at least 25% of diverted textiles undergo fiber-to-fiber recycling rather than downcycling.

Early implementation has catalyzed private investment in recycling infrastructure. Renewcell announced a $180 million chemical recycling facility in Stockton, California, with 60,000 tons per year of cellulosic fiber capacity, scheduled for operation in 2027. Eastman Chemical committed to expanding its Kingsport, Tennessee methanolysis facility to process 110,000 tons per year of polyester textiles by 2028, with California-sourced feedstock representing 30% of projected input (CalRecycle, 2025).

What's Not Working

Blended fabrics remain a persistent challenge. Approximately 60% of garments on the market contain blends of two or more fiber types (polyester-cotton being the most common at 35% market share). Neither mechanical nor most chemical recycling processes can efficiently handle blends without first separating the component fibers. Circ's hydrothermal process is one of the few technologies that can separate polyester-cotton blends, but the process adds $200 to $350 per ton in processing cost compared to single-fiber feedstock. Several pilot programs have reported that blended-fabric textiles accumulate in storage because no economically viable processing route exists, creating bottleneck inventory that undermines collection program economics.

Collection participation remains inconsistent. Even in San Francisco, where environmental program awareness is high, textile collection bin utilization varies dramatically by neighborhood. Bins in high-density residential areas average 85% capacity utilization, while suburban locations average 35%. New York City data shows that 40% of collected textiles still come through traditional donation channels (Goodwill, Salvation Army) rather than municipal collection infrastructure, creating parallel and sometimes competing collection streams.

Sorting labor costs are a significant barrier. While automated NIR sorting dramatically increases throughput, the technology requires garments to be presented individually on a conveyor belt. The pre-sorting step of opening bags, removing non-textile contaminants, and singulating garments remains labor-intensive, accounting for 40 to 55% of total sorting facility operating costs. Facilities in high-wage markets like San Francisco and New York report all-in sorting costs of $120 to $180 per ton, versus $40 to $60 per ton at facilities in lower-cost regions.

Recycled fiber quality gaps persist for cotton. Mechanically recycled cotton fiber is demonstrably inferior to virgin cotton in staple length, tensile strength, and uniformity. Brands including Patagonia and H&M have publicly stated that recycled cotton content above 30% in a garment compromises product quality and durability. This quality ceiling limits the addressable market for mechanically recycled cotton and depresses pricing relative to virgin fiber.

Key Players

Established Companies

• Eastman Chemical: operates commercial-scale polyester methanolysis, converting PET textiles back to virgin-quality monomers at its Kingsport, Tennessee facility
• Lenzing Group: produces REFIBRA lyocell fiber incorporating up to 30% post-consumer cotton textile waste through its proprietary dissolution process
• Martex Fiber Southern: one of the largest mechanical textile recyclers in the US, processing 100,000+ tons per year at facilities in South Carolina and Georgia

Startups

• Circ: developed hydrothermal chemical recycling technology capable of separating and recycling polyester-cotton blends, raised $100 million Series B in 2024
• Renewcell: Swedish startup producing Circulose dissolving pulp from post-consumer cotton textiles, expanding to US operations
• Ambercycle: Los Angeles-based company using engineered enzymes to selectively depolymerize polyester from blended textiles, raised $45 million in 2024

Investors and Funders

• Closed Loop Partners: invested in multiple textile recycling startups and infrastructure projects through its circular economy fund
• H&M Foundation: committed $100 million to textile recycling technology development through its Planet First initiative
• US Department of Energy: awarded $12 million in grants for textile-to-textile recycling technology development under the 2024 Bioenergy Technologies Office program

Action Checklist

• Conduct a textile waste characterization study to quantify volumes, fiber composition, and contamination rates in the municipal waste stream
• Establish dedicated textile collection infrastructure with a minimum of one collection point per 2,000 residents in urban areas
• Deploy QR-coded or RFID-tracked collection bags to measure participation rates and contamination by source
• Partner with automated sorting facilities using NIR spectroscopy to achieve >95% fiber identification accuracy
• Secure offtake agreements with both mechanical and chemical recyclers before scaling collection to avoid feedstock accumulation
• Develop public education campaigns emphasizing that textiles should be clean, dry, and free of non-textile items
• Evaluate EPR policy frameworks to shift collection and recycling costs to producers and create long-term funding stability
• Establish contamination thresholds (target <10%) and implement corrective action protocols when thresholds are exceeded

FAQ

Q: What is the minimum scale needed for a municipal textile recycling pilot to be economically viable? A: Based on existing pilot data, a collection volume of at least 2,000 tons per year is needed to justify dedicated sorting infrastructure and achieve competitive pricing from downstream recyclers. Cities collecting less than this threshold should consider regional partnerships or aggregation with neighboring jurisdictions. San Francisco's program reached break-even economics at approximately 3,000 tons per year when accounting for avoided landfill costs and fiber revenue.

Q: How does chemical recycling of textiles compare to mechanical recycling in terms of cost and output quality? A: Chemical recycling produces virgin-quality fiber but at higher cost. Current chemical recycling costs range from $800 to $1,200 per ton of input feedstock, versus $200 to $400 per ton for mechanical recycling. However, chemical recycling output commands premium pricing ($1,400 to $1,800 per ton for recycled polyester) and can handle blended fabrics that mechanical processes cannot. For cotton, chemical dissolution into regenerated cellulose fiber costs $600 to $900 per ton but produces fiber with properties superior to mechanically recycled cotton.

Q: What contamination challenges do municipal textile collection programs face? A: The three most common contamination issues are: non-textile items placed in collection bins (shoes, bags, household goods), wet or soiled textiles that develop mold and contaminate adjacent clean materials, and textiles with non-removable hardware (large metal zippers, heavy embellishments) that damage shredding and sorting equipment. New York City's experience shows that clear labeling, regular bin servicing (weekly minimum), and QR-tracked bags that allow feedback to users can reduce contamination from 18% to below 7% within six months.

Q: Which fiber types are most and least recyclable with current technology? A: Pure polyester (PET) is the most recyclable textile fiber, with both mechanical and chemical pathways producing commercially viable output. Pure cotton is moderately recyclable through mechanical and chemical dissolution processes. Nylon 6 can be chemically recycled through depolymerization. The most challenging materials are polyester-elastane blends (common in activewear), wool blends, and garments with multiple fiber types in layered constructions. These materials currently have no commercial-scale fiber-to-fiber recycling pathway and typically end up downcycled or landfilled.

Q: How long does it take to see measurable diversion results from a new textile recycling program? A: San Francisco's experience indicates that meaningful diversion volumes require 12 to 18 months from program launch. The first 6 months are typically dominated by infrastructure deployment, public awareness building, and collection logistics optimization. Diversion rates accelerate in months 6 to 12 as bin utilization increases and collection routes are optimized. Stable-state operations, with predictable volumes and established downstream relationships, typically emerge at 18 to 24 months.

Sources

• US Environmental Protection Agency. (2025). Advancing Sustainable Materials Management: 2023 Fact Sheet. Washington, DC: US EPA.
• Council for Textile Recycling. (2025). The State of Textile Recycling in the United States: 2024 Annual Report. Bethesda, MD: CTR.
• Ellen MacArthur Foundation. (2024). A New Textiles Economy: Redesigning Fashion's Future, 2024 Progress Report. Cowes, UK: EMF.
• San Francisco Department of Environment. (2025). Textile Recovery Pilot Program: 18-Month Performance Report. San Francisco, CA: SFE.
• NYC Department of Sanitation. (2025). Refashion NYC: 2024 Annual Textile Diversion Report. New York, NY: DSNY.
• CalRecycle. (2025). SB 707 Textile EPR Implementation Plan: Regulatory Framework and Industry Requirements. Sacramento, CA: CalRecycle.
• Global Fashion Agenda. (2025). Scaling Textile-to-Textile Recycling: Technology Readiness and Market Analysis. Copenhagen: GFA.
• Textile Exchange. (2025). Preferred Fiber and Materials Market Report 2024. Lamesa, TX: Textile Exchange.