Improved Gray Water Footprint Calculation and Assessment Method for Polyester Fabric Production

Gray water footprint has been widely used as an indicator to quantify the water environmental impact of textile products. Traditionally, gray water footprint values are determined by the largest gray water footprint value of the typical water pollutant. The performances of other critical compounds that coexist in wastewater are disregarded. To mitigate these shortcomings associated with gray water footprint accounting and assessment, an improved gray water footprint calculation and assessment framework is proposed in this study. The diffusion and attenuation process of pollutants in rivers was considered for the comprehensive accounting and evaluation of the impacts caused by various pollutants in discharged wastewater. Polyester fabric production was used to illustrate the application of the improved gray water footprint calculation and assessment method. The results revealed that chemical oxygen demand caused the most severe water eutrophication impact and antimony caused the most severe water ecotoxicity impact. The comprehensive evaluation of improved gray water footprint indicated that alkali peeling process caused the largest water environmental impact during polyester fabric production.