Regulatory agencies in parts of India mandate textile dyeing units to implement zero-liquid-discharge (ZLD) or nearly complete effluent recycling. Since salts are used in the dyeing process, desalination is an integral step to achieve this.

In this project, we aim to reduce the energy consumption of the desalination step, thereby reducing overall system cost. The choice of chemicals used in the dyeing processing steps will impact the energy consumption for water recycling. At low salinity levels, nanofiltration can be a potentially cheaper alternative to reverse osmosis, and at higher salinity levels, membrane distillation could enable smaller-scale desalination compared to mechanical vapor compression or multiple effect evaporator systems.

Project Media

• Jai Swaminathan using math to help save India’s textile mills
• The Hindu: Low-cost desalination system for dyeing units