Evaluation of hydrophilic cotton processing wastewater treatment methods and giving the optimum method for it

We studied the methods of wastewater treatment of hydrophilic cotton producing industries. Several major cotton producing countries, such as India, have provided very stringent environmental standards for these industries, and it is expected that these standards are becoming more stringent day by day. This is necessary for monitoring and control facilities, in order to minimize problems and difficulties associated with treated wastewater disposal. Unit processes of these industries are: pretreatment, dyeing, printing and other complementary processes. In this industry, aside from considerable amounts of energy and water consumption, considerable quantity of wastewater is also produced. This article discusses all types of waste producing hydrophilic cotton processes; we have also advanced wastewater treatment methods, such as electrical oxidation, membrane processes, biological and photochemical treatments. Results showed that traditional methods of wastewater treatment are compound methods including physical–chemical and biological methods, and requires substantial investment and operational costs. Compared to traditional methods, membrane systems are very effective methods and are a good substitute. Investigation showed that hybrid treatment methods that include absorption and absorption by nano-filtration can play an effective role in improving treated wastewater quality. Moreover, advanced treatments such as ion exchange systems can improve wastewater quality to the extent that it can be recycled to the production processes for second usage.