Investigation And Application Of New Technology For Deep Water Saving And Emission Reduction Dyeing Of Cashmere Fiber

At the end of the traditional cashmere dyeing with reactive dyes,alkali washing and multiple hot and cold water washing processes are necessary to ensure the dyeing color fastness.However the cumbersome hot and humid processing process not only caused damage to the cashmere fiber,and it has a long duration,large water consumption,and high residual pollution load in the entire processing.In order to solve the above problems,a set of new technologies for deep water-saving and emission reduction dyeing of cashmere,which is also called in-situ mineralization dyeing technology for cashmere was developed in this project.That is,no residue will be discharged after dyeing,and through the mineralized coupling agent developed by our lab,the residual chemicals such as the residual dyes,chemical additives,and unfixed dyes on the surface of the fiber,were decomposed into colorless small molecules,carbon dioxide,and water.Meanwhile this technology reduced the subsequent washing process,with the premise of guaranteeing the excellent performance of the dyeing products,and the production energy consumption and the pollutant discharge amount is reduced greatly.Finally,the goal of deep water saving and emission reduction was achieved.In-situ mineralized dyeing process was performed on cashmere using the reactive dyes of Yilansu series,and the in-situ mineralization dyeing process of cashmere was determined by a single-variable-variable analysis method,dyeing stage:XPN-MX dosage was 1.5%（owf）at 90℃for 70 min,mineralization stage:in-situ mineralization temperature was 85℃,mineralization bath pH value was3-4,in situ mineralization coupling agent XBM dosage of 0.5%（owf）,in-situ mineralization coupling agent XYS dosage was 3.0%（owf）and the mineralization time was 30 min.Comparison of dyeing pilot and production tracking tests with traditional techniques shows that the in-situ mineralization dyeing process is used to dye the cashmere,with the same amount of dye,the color of the dyed product is deeper than that of the traditional process,in addition,the physical and chemical properties of dyed products are excellent,the water saving rate is about 75%,the total residual COD_Crr reduction rate is about 69%,the color reduction rate is about 96%,the production efficiency is improved,and the goal of deep water saving and emission reduction is achieved.The mineralization process shortens the post-processing wet heat processing process can reduce the damage of cashmere fiber.Specifically reflected in the fiber surface friction coefficient is smaller and the fiber structure of the scale is relatively complete,the surface is bright and smooth,in addition the feeling of cashmere fiber is fluffy,this will have a positive impact on the spinning of dyed cashmere and will also lay the foundation for the preparation of high-quality cashmere products...