With two cutting-edge studies, the Hong Kong Research Institute of Textiles and Apparel (HKRITA) is focusing on indigo. The first is a mechanical recycling technology powered by artificial intelligence that pulls reused warp strands from denim garments that have been dyed blue. This method, which addresses the difficulties of recycling denim mixed with other materials, is the first of its kind and is devoid of chemicals and water. They don’t require further dying thanks to the system for producing new denim.
The procedure separates warp yarns, which are usually created from premium dyed cotton, with an amazing 90% efficiency. The invention lowers the need for virgin cotton, the negative effects of denim dyeing on the environment, and the expenses related to dyeing and wastewater.
HKRITA’s second project explores a biodegradable mechanism to remove indigo dye from wastewater using sunlight and macroalgae species like Cladophora and Chaetomorpha. This algae-based system degrades the dye and consumes carbon dioxide emitted from denim factories, offering a cost-effective, energy-efficient, and eco-friendly solution to reducing dye pollutants in wastewater.
The main challenges lie in scaling these systems for industrial use. For the wastewater treatment project, scaling involves adapting the design for light penetration, water circulation, and macroalgal containment. Similarly, the mechanical warp-weft separation system needs to be scaled up to meet industrial production efficiency.