The Potential of Membrane Technology for Treatment of Textile Wastewater

Abstract

The textile industry is characterized by being a very demanding consumer of high-quality water. Thus, both quantity and quality of water are key issues that affect this sector considerably. However, in a global context in which water is becoming the twenty-first-century paragon, the choice of wasting water is not anymore acceptable. The textile industry is facing thus a double objective: to minimize drastically the water consumption while using water with high quality. This objective involves that (1) reuse of water is essential, and (2) effective and economic processes to recover the quality of water are required. Membrane technology offers the possibility to do that at low expenses. The potential of membrane technology to treat wastewater and recover both the water itself and the pollutants (organic and inorganic substances), which become then valuable compounds, has been demonstrated in the recent research. Nanofiltration is one of the most attractive technologies for this application since nanofiltration membranes can retain ions and small organic molecules from an aqueous solution. But it is also very challenging due to the presence of salts and operating problems such as fouling, salt deposition, etc. This book chapter summarizes the main achievements of nanofiltration in the textile industry, focusing on three different scenarios: (i) nanofiltration as stand-alone technology; (ii) nanofiltration in hybrid processes, and (iii) nanofiltration in water fractionation (recovery of water, dyes and salts). The last advances on nanofiltration as well as the main limitations and challenges still to be faced are also described in order to guide the reader toward further research.