Significant systems gaps still exist in technology and capacity for sorting, pre-processing and recycling, and products need to designed with recycling in mind when it comes to polyester-based textile recycling, according to a new study by nonprofit Accelerating Circularity.
- Legislation has propelled other polymer dependent industries—such as plastics—forwards in recycling technology development, but textiles still have some way to go.
- The report, Truth or Consequences: The Global Polyester Report, is based on two series of system trials, one in the US and the other in Europe, aimed to address recognised gaps in circular textiles capabilities by bringing together all the systems stakeholders from the value chain to develop processes, relationships, business models, and materials necessary for enabling the transition of the textiles industry from a linear to a circular system.
- The study that began in 2022 saw participation from 43 companies from all levels of the industry, including textile collection, sorting, recycling (both thermomechanical and chemical), yarn spinning, knitting, weaving, manufacturing, and retail.
THE LEARNINGS: The project study has classified the learnings under three heads: sorting, pre-processing and recycling.
Lessons in sorting: Automation and effective training are essential for improving efficiency, while addressing contaminants in feedstock is crucial for successful recycling outcomes.
- Automated sorting technology predominantly uses NIR (Near Infrared) technology to detect fibre composition. The use of NIR technology significantly enhances accuracy compared to manual sorting. In one trial, automated technology reduced feedstock loss by 36% compared to manual sorting.
- The use of hand-scanners based on NIR technology can be used to improve the manual sorting of feedstock but they affect speed on the sorting line.
- Although sorting technology that can detect the fibre composition of entire garments using NIR technology is becoming more widely available, the de-trimming process remains entirely manual.
- A trial showed it to be a misconception that workwear is consistently sorted by composition and therefore readily recyclable sorting and segregation processes still need to be implemented with care.
Lessons in pre-processing: De-trimming, still an entirely manual process in both the EU and US, is a bottleneck in terms of physical capacity and time taken. In some cases, material needed to be shipped to another country for de-trimming.
- To ensure accuracy in de-trimming, adequate guidelines need to be set, and staff need to be trained. For accuracy and speed it is key to categorise common trims and their locations per product category of feedstock
- De-trimming does not equal pre-processing: the required pre-processing is bespoke to the recycling technology.
- De-trimmed garments can be accepted, but feedstock may also need to be guillotined to specific sized pieces or need an ‘agglomeration’ or ‘compaction’ process to make it compatible with a recycling technology.
