Water footprint calculation and assessment of viscose textile

Abstract

Water footprint is used as an indicator to quantify the impacts on water resource and water environment. Based on water footprint standards established by the International Standardization Organization (ISO), this paper proposed a new quantitative indicator for water alkalization, and calculated the water footprints involved in viscose textile production. In addition, water footprint accounting results were comprehensively evaluated by LCA polygon method which was developed to interpret LCA results. Results showed that: (1) water scarcity footprint of viscose textile production was 60.511 m3 H2O eq/ton, of which 85.71% was from the viscose fiber production; (2) water eutrophication footprint of viscose textile production was 12.439 kg PO43- eq/ton, the major contribution (84.37%) was given by COD and BOD5; (3) water acidification footprint and water alkaline footprint of viscose textile production were 81.453 kg SO2 eq/ton and 55.675 kg OH- eq/ton, mainly due to H2SO4 and NaOH input during the spinning process, respectively; (4) water ecotoxicity footprint of viscose textile production was 3828.169 km3 H2O eq/ton, mainly derived from Zn2+ in spinning wastewater; (5) LCA polygon analyses showed that environmental load in the spinning was the largest, followed by the pulping and then the dyeing.