New Delhi: India accumulates around 3.9 million tons of domestic post-consumer textile waste (the discarded textiles and clothing after their use) annually of which only 4% is recycled. Most of these textile wastes go to landfill and remain there for hundreds of years.

Recycling of post-consumer textile waste is challenging due to variability in colour and fibre blend. The quality of clothing produced by recycling post-consumer textiles is inferior compared to that of virgin textiles due to loss in fibre strength and reduction in fibre length during mechanical recycling.

A team of researchers from IIT Delhi has developed a method to recycle denim waste to knitted garments without compromising quality. Waste denims were recycled into yarns ensuring minimum damage to the fibre properties by optimising the process conditions. Recycled yarns were then blended into knitted fabric using the seamless whole garment technology. Knitted garments were produced varying the recycled yarn content from 25% to 75%.

The research team led by Prof. Abhijit Majumdar and Prof. B.S. Butola of Textile and Fibre Engineering department found that up to 50% of recycled yarns can be used in knitted clothing without deteriorating the feel of the product.

“To reduce the roughness of recycled yarns, a softening treatment was applied to the fabric which ensured that the tactile feel of the final product is same with that of virgin products,” said Prof. Abhijit Majumdar, Dept. of Textiles and Fibre Engineering, IIT Delhi

Prof. Majumdar added, “We have demonstrated our work with denim waste, and it can be extended with any other textile waste.”

Outcome of this research has been highlighted in a recent publication of Journal of Cleaner Production. Another key aspect of this research was to quantify the environmental benefits through life cycle assessment (LCA) in the Indian context.

PhD scholar Satya Karmakar, who is working in this project, collected the energy and materials related data from Panipat textile recycling cluster. Analysis by the IIT Delhi team has shown that around 30-40% environmental impacts can be mitigated in terms of greenhouse gas emission, acid rain, and fossil fuel depletion whereas for ozone layer depletion it is around 60%.

As the use of recycled fibres could reduce the use of virgin cotton; the pesticides, fertilisers and water used for cultivation can be saved. Among the processes involved, cotton cultivation stage itself contributes 24% to the global warming making the virgin yarns less environment friendly.

“The research team is now exploring the possibility of recycling textile waste materials for multiple times,” added Prof. B.S. Butola, Dept. of Textile and Fibre Engineering, IIT Delhi.

                                                  (Photo: Recycled seamless garment from post-consumer denims)

                              Environmental benefits quantified through Life Cycled Assessment (LCA)

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Press Release issued on 08-08-2025