National Torch Plan - Integrated Industrialization Project for Zero Discharge Treatment and Reuse of High Salt Printing and Dyeing Wastewater

The textile industry, as a key development industry in Xinjiang, is a crucial link in the entire textile industry chain, and the scarcity of water resources and fragile water ecological environment are the key limiting factors for the development of printing and dyeing in Xinjiang. Developing technologies for the treatment and deep reuse of printing and dyeing wastewater, improving the treatment and reuse rates of wastewater, and applying recycled water to production water and urban miscellaneous water in the printing and dyeing industry are of great significance for alleviating the water shortage situation in this industry. The zero discharge of wastewater eliminates the need for enterprises to pay high sewage fees. The separation and evaporation of high concentration saltwater, as well as its quality utilization, turn waste into treasure and have good economic benefits.

This project has developed high-performance and low-cost membrane materials, including ultrafiltration membranes, nanofiltration membranes, and electrodialysis bipolar membranes, which have improved wastewater treatment efficiency, reduced membrane technology integration process costs, and developed an integrated technology for the reuse of high pollution and high salt wastewater from printing and dyeing, mainly based on membrane separation technology, to achieve the reuse of water for production and miscellaneous use in the factory area. Developing zero discharge and refined salt integration technology for concentrated salt water, achieving the resource utilization of by-product salt. Shihezi Textile Industrial City has been built into a demonstration project with a daily treatment capacity of 1000 tons of high concentration and high salt printing and dyeing wastewater, achieving a COD removal rate of over 99.7%, a salt removal rate of over 98.5%, a reuse rate of not less than 30%, and a treatment cost of ≤ 40 yuan/ton.

This technology has obtained achievement appraisal and won the second prize of Science and Technology of the Membrane Industry Association in 2018.