Sustainable Chemistry and Pharmacy, cilt.39, 2024 (SCI-Expanded)
The environmental impacts of membrane treatment for salt and water recovery from reactive dyeing wastewater are assessed using the Life Cycle Assessment (LCA) framework. Three membrane treatment options (UF-only, NF-only, and UF + NF) with proven but different salt and water recovery efficiencies from three different reactive dyeing effluents (jigger dyeing, jet dyeing, and pad-steam dyeing) is considered. The functional unit is defined as “1 ton of fabric dyed'. Reactive dyeing process inventory data were obtained from 21 textile mills in Turkey, while data for membrane treatment were derived using the WAVE software. Results indicated that UF-only treatment surpasses direct discharge for all dyeing methods, demonstrating a considerable reduction in environmental impact. However, NF-only and UF + NF treatments, offering significant salt retention, show either equal or higher overall environmental impacts, owing to the energy-intensive nature of membrane processes, particularly NF. Predominant environmental impacts were identified in fine particulate matter formation and global warming-human health impact categories, with steam and energy consumption, along with dye usage in the dyeing process, as primary contributors. Building upon the results and identified hot spots, sensitivity analysis focusing on the use of electricity in membrane treatment and the use of steam in dyeing, was conducted. Transitioning to 100% renewable energy in membrane treatment significantly reduced total environmental impact, resulting in NF and UF + NF treatment scenarios exhibiting lower impacts compared to direct discharge scenario. The research suggests textile producers choose the optimal membrane treatment for salt and water reuse, considering permeate quality needs, and environmental impacts.