The Hong Kong Research Institute of Textiles and Apparel Limited (HKRITA) has developed a mechanical method for separating warp and weft yarn from denim fabrics without the use of water or chemicals.
- It offers a recycling alternative for denim fabric even with lower cotton purity.
- The method addresses the challenge of minimising fibre damage using existing mechanical recycling technologies.
- The project won a Bronze Medal in the 49th International Exhibition of Inventions of Geneva this April for its innovative attempt to recycle denim fabric in a mechanical approach.
THE SYSTEM: This AI-driven mechanical recycling system provides essential parameters to facilitate the separation of the warp yarn from the denim fabric.
- The mechanism relies on direct mechanical extraction, minimising the need for chemicals.
- The efficiency of separating warp yarns is over 90%, making them suitable for garment recycling.
- These advancements contribute to the development of a circular economy, promoting sustainability in the textiles industry.
THE METHOD: First, the denim fabric is placed on a conveyor. The AI system identifies the fabric’s weaving structure and measures both the warp yarn density and fabric orientation. Denim fabric within the system’s parameters is transferred to the next station and cut into four sections for easier separation.
- Next, extraction pins pierce through the fabric’s front and pull out the warp yarns. Then, a pair of roller grippers will grab the pulled-out warp yarn and extract the entire warp yarn from the fabric.
- Once the weft yarn reaches a certain length, it is severed by a rotary cutter to avoid entanglement with the warp yarn during extraction. The separated warp yarns and weft yarns are suctioned away and stored separately in two different collection boxes.
