Life cycle assessment of textile fibre-to-fibre recycling by cellulose carbamate technology

Abstract

The fashion industry faces major challenges in reducing its environmental impacts along the textile value chain, from fibre production, via various processing steps, use phase and to the end-of-life stage. A major challenge is how to shift from the current linear industry to a circular one, where textiles are both sustainably produced, and after the full life length, recycled into new fibres with high value applications. The aim of this study was to evaluate the environmental impacts of post-consumer textile fibre-to-fibre recycling by cellulose carbamate technology, in terms of climate impact, water scarcity impact, cumulative energy demand and land use impact. By performing life cycle assessment, it was shown that the chemically recycled cellulose carbamate fibre has a climate impact of about 2.2 kg CO2-eq per kg fibre, water scarcity impact of 1.6 m3 H2O-eq per kg fibre, cumulative energy demand of 90 MJ-eq per kg fibre and land use impact of about 92 Pt per kg fibre (when applying mass allocation of co-products). Hotspots identified during the fibre production technology were electricity use and production of sodium hydroxide. In a sensitivity analysis, it was shown that the choice of electricity has a major influence on the results, and by using a renewable electricity mix over an average Finnish electricity mix, the impact could be decreased for all impact categories, except when using bioenergy, which would increase the land use impact. Compared to primary fibres like viscose and conventional cotton, these impacts are in the lower to middle range, showing potential to lower environmental impacts when moving towards an increased amounts of recycled post-consumer textile fibre with high value applications, that can replace primary fibres.