Water footprint assessment of silk apparel in China

Abstract

Water resources are vital to ecosystems and human beings and play a significant role in the textile and apparel industry. With an increased impact on the limited water resources, there has been increasing attention on the use of water footprint assessment (WFA) in textile research. In this study, a comprehensive water footprint assessment was conducted on the production chains of silk crepe de chine (CDC) dresses and silk brocade dresses based on the ISO 14046 standard and life cycle assessment polygon method. The results of the WFA showed that brocade dresses had a greater contribution to both the water scarcity footprint and water degradation footprint than the CDC dresses. The silk reeling process had a greater impact on water quantity and water eutrophication while the dyeing and finishing process had a greater impact on water acidification and water ecotoxicity. The leading contributors to the water eutrophication footprint were chemical oxygen demand (COD) > NH3–N for the silk reeling process and total nitrogen > COD > total phosphorus for the dyeing and finishing process. The leading contributor to water acidification was sulfides generated from the utilization of acid dyes. The leading contributors to the water ecotoxicity footprint were Hg > Sb > Cu > Zn for both dresses. The production of brocade dresses and the dyeing and finishing process had a significant environmental impact on water resources for products and processes, and are thus key factors to be considered in future water management. In order to reduce the water footprint of the textile industry, water reuse and improved wastewater treatment and manufacturing technology should be prioritized, along with the use of environmentally-friendly dyes.