Recycling used denim to give colour to new denim is a revolutionary idea which has just been recognised by a major international award. The team, containing four Hub members, were one of five winners of the Global Change Award, an initiative of the H&M Foundation to promote sustainable fashion. They were awarded €150,000 for further development of their ‘denim-dyed-denim’ concept.
Hub Director, Professor Xungai Wang, led the team which included Hub researchers Dr Rangam Rajkhowa, Dr Nolene Byrne and Dr Christopher Hurren as well as Dr Rebecca Van Amber. They were presented with the award at a dinner in Stockholm on 5th April 2017.
“Denim is the single largest apparel item on the market. Traditional denim production has a serious environmental impact and denim recycling is a huge issue worldwide,” Professor Wang said. On average, the life cycle of a pair of denim jeans produces more than 30 kg of CO2 and uses around 3500 litres of water. The Circular Denim project would significantly reduce water and energy consumption, addressing key issues in denim production.
“This way, the old denim is reused, and new denim does not have to be dyed using the traditional yarn dyeing approach which consumes a huge amount of water and energy,” Dr Rangam Rajkhowa said. “If necessary, the colour of the fine particles can be enhanced or changed easily before the coating or printing process. This will also help create a new fashion effect for denim products.”
Professor Wang said that the key to the project’s success in improving the environmental sustainability of denim production came from the team’s unique ability to create ultrafine coloured particles from used textiles that can then be used as a dye.
“Our previous work shows that pulverised fibre particles can take up dye under room temperature within five minutes due to very high surface area, hence significantly reducing the energy used to heat water under conventional dyeing process,” he said.
“This process also allows dye to be reused, minimising water use and effluent discharge.
Researcher Dr Chris Hurren added that very fine particles from one pair of jeans could be used to dye 10 new jeans.
The team has already developed a successful prototype and plan to use the Global Change Award funding to scale up the idea and work with denim producers and fashion brands to explore its potential.
“Our ‘circular denim’ approach is a completely new one, addressing both denim waste and new denim manufacturing at the same time, and we believe it will have a lasting impact on both the environment and the global clothing market.”