Water efficiency and wastewater reduction in an integrated woolen textile mill

Abstract

The most important environmental issues caused by the textile industry are intensive water consumption, high amounts of wastewater generation with significant pollutant loads. Previous studies were focused on minimization of water consumption and wastewater amounts in cotton textile finishing-dyeing. There are very few real-scale scientific studies about water efficiency in woolen textile production. In this study, it was aimed to reduce water consumption, wastewater amount and its pollutant loads by appropriate techno-economical minimization techniques in an integrated woolen textile mill. In this context, water consumptions and wastewater generations in basic and other auxiliary processes of the mill were examined by detailed on-site investigations. Process based specific water consumption and wastewater values were calculated. Additionally, water and wastewater samples were collected at different periods and analyzed. Specific pollutant loads of wastewater were also calculated. Thus, reuse potentials of the process wastewaters were evaluated. Moreover, saving and reduction potentials of the mill were determined by comparing with similar textile mills. Total of 82 minimization techniques were identified and evaluated by using multi-criteria decision-making methods. As a result, it was decided to implement 9 minimization techniques in the mill. Thus, reductions in water consumption by 41–69%, wastewater amounts by 48–75% and wastewater chemical loads by 28–63% can be achieved by the implementation of the minimization techniques. Potential payback period was ranged between 24 and 60 months. Employed methodology and findings of the study may be useful to similar textile mills, stakeholders and regulators. Presented results may also provide a road map to textile industry for cleaner production applications.