New Technology Realizes Zero Discharge Textile Dyeing Without Reusing Water.

Recently, Yu Jianyong, academician of the Chinese Academy of engineering, came to the Qingdao development group in Jimo District of Shanghai to investigate its textile supercritical CO2 waterless dyed dyeing production line. It indicated that the construction of the world's first and largest intelligent waterless dyed dyeing demonstration line marked the maturity of China's anhydrous dyeing process and achieved a major breakthrough in industrialization.

At present, the annual discharge of textile waste water in China is 25 million tons (about 230 West Lake water), of which printing and dyeing wastewater discharge is 20 million tons. Due to the dependence of traditional dyeing and printing on water resources and environmental problems caused by wastewater discharge, the sustainable development of the whole industry is restricted.

Therefore, it is urgent to develop a less water or no water dyeing technology to solve the bottleneck problem of printing and dyeing industry from the source.

As early as 2014, the group started the industrialization and research and application of supercritical CO2 anhydrous dyeing technology through the cooperation of industry, University and research, and constantly improved and improved the technology of waterless dyeing. It solved many key technical problems affecting the industrialization of equipment, technology and testing, and conquered the bottleneck of professional components.

The semi liquid state of supercritical fluid can not only dissolve dyes, but also easily penetrate into the interior of textiles. The dye dissolution, adsorption and dyeing process can be completed, eliminating the main shortcomings of the traditional water dyeing process, reducing the dyeing cycle from a few hours to a few minutes, and achieving zero emissions, environmental protection and high efficiency.

In 2017, the group started the construction of the world's first 1200L free water dyeing industrialization demonstration production line with independent intellectual property rights, and realized the continuous normal operation of the equipment. At present, more than 30 patents have been applied, laying a solid foundation for industrial application.

Wan Gang, deputy general manager of the group, said that the implementation of the industrialization project of the supercritical CO2 water free dyeing technology for polyester material used in textile industry is a high-tech field supported by the state. It will play a positive role in promoting the construction of a conservation minded society, creating a resource conserving and environment-friendly enterprise, and vigorously developing new manufacturing processes and equipment with high efficiency, energy saving, environmental protection and recyclability.