Research on Cleaner Production Technology of Textile Printing and Dyeing Industry
With the rapid development of social production and the acceleration of industrialization, environmental pollution has become increasingly prominent. Industrial production and urban construction of wastewater generated as a serious source of pollution. Water pollution leads to water shortage and deterioration of water quality, which has become an important factor restricting economic and social sustainable development. Therefore, the control and prevention of wastewater pollution has attracted more and more people's attention, and the implementation of clean production has become the inevitable trend of social and economic development.
However, a single terminal treatment has become a heavy burden of economic development, and can not effectively solve the problem of environmental pollution, the need to reconsider the environmental governance policy.Therefore, the treatment of waste water and waste water, In this regard, the developed countries pioneered a new way to promote the coordinated development of economy and environment - cleaner production.
With the deepening of cleaner production, the world in practice continue to open up new areas, from the initial chemical industry gradually expanded to the first, second and tertiary industries. Although there is no mature printing and dyeing industry, cleaner production indicators and technical specifications, but we can learn from other companies the successful experience of cleaner production. The introduction of cleaner production theory. The implementation of clean production of printing and dyeing industry, can fundamentally prevent and reduce pollution of the environment, to ensure continuous improvement of environmental quality.
First, the printing industry, the concept of cleaner production and content
The clean production of the printing and dyeing industry is the continuous application of pollution prevention strategy to the whole process of dyeing and printing production. By adopting scientific and rational management, the printing and dyeing technology is continuously improved to improve the utilization rate of raw materials and reduce pollutant emissions. To reduce the environmental and human hazards. The implementation of cleaner production is to solve the environmental problems of China's printing and dyeing industry, the production of safe and qualified products to achieve the sustainable development of printing and dyeing enterprises an important means of printing and dyeing industry, cleaner production throughout the production and disposal of waste the whole process. The whole process control of production includes clean energy and raw material input, clean working environment and clean printing and dyeing products. The whole process of waste disposal includes the process of waste reduction, harmless and resource utilization in printing and dyeing industry.
Second, dyeing and finishing clean production technology pre-treatment process
Pretreatment process of waste water is very impressive, accounting for the amount of printing and dyeing wastewater 5O% ~ 6O%, saving water is of great significance. The use of efficient short process technology, the use of efficient additives, shorten the processing time, can reduce the amount of additives and water. Compared with the traditional three-step process of retreat, boiling and bleaching, it can save about 2 times of water, 1.8 times of energy-saving, 3 times of saving steam, and its resource saving And the energy effect is obvious; the use of low-temperature, low-alkali pretreatment process can save energy, but also reduce the amount of alkali waste water, which will help wastewater treatment; development of a new generation of green surfactants, ecological additives in the pre-treatment process Technology, such as biological enzyme desizing, refining and other biological enzyme pretreatment technology, not only can avoid the use of alkali, greatly reducing the use of chemicals to reduce waste water discharge, but also improve the biodegradability of pollutants in wastewater. Compound biological enzyme can be used in alkali-free annealing process at room temperature, high temperature alkali removal of gray fabric and its co-organisms have also been gradually began to compound enzyme desizing refining alternative. For some textiles containing less impurities, can use a small bath or foam bath, in less water conditions. In recent years, the use of plasma technology or other ion sputtering technology, laser technology, ultrasonic technology and ultraviolet radiation technology to remove the fabric surface impurities have made great progress.
Third, dyeing and finishing cleaner production technology of the dyeing process
Dyeing process is the main process of dyeing industry, in the process of promoting clean production of great significance. Such as the modification of fiber to improve its dyeing performance and application of high fixing rate and high utilization of the dye, the development of high dye utilization of the dyeing process, the equipment is a very good method of cleaner production. BURKINSHAW and other research that dendrimers pretreated cotton fabric can significantly increase the dye uptake rate, even up to salt-free staining. Researchers in the fabric modification of reactive dyes to achieve salt-free dyeing also done a lot of research work.
The use of ultraviolet, microwave and high-energy-ray treatment of textiles, can also improve the dyeing properties of fiber, and some can be directly used for fixing. (1: 4) ~ (1: 6), not only can save dyes and additives, but also reduce the amount of waste water and dye residue, can save 30% dye material, saving 40% water consumption. Some scholars have studied the use of ultrasonic dyeing in a short time in low temperature dye uptake rate increase, saving energy.
One of the aims of cleaner production is to minimize the consumption of water, dyestuffs and energy, which is made possible by waterless dyeing techniques. Non-aqueous or non-aqueous dyeing is an important method of clean dyeing. In recent years, the application of supercritical carbon dioxide as a staining medium, dyeing without water, after dyeing under normal circumstances without washing or mild washing, carbon dioxide can be reused. This method has the advantages of no water, no pollution, short dyeing time, low energy consumption and recyclable residual dye, which is a direction of future dyeing development.
Fourth, dyeing and finishing clean production technology printing process
Printing paste pollution is more serious. At present, some new type of paste is mainly through the modification of natural polymer compounds and the use of petrochemical raw materials and synthesis. These new types of paste are used in low amounts for easy recovery and purification. Paint printing process is short, without washing, in line with the principles of ecology, should actively develop new coatings, adhesives and efficient thickener, to solve the hand, fastness and vividness. In recent years, printing technology has developed rapidly, digital inkjet printing, transfer printing, electronic photographic printing and other green printing technology has made continuous development. Digital inkjet printing can save a certain amount of water, is in line with clean production requirements of the production process. Transfer printing in the production process to achieve water or less water printing. Natural fiber fabric transfer printing water consumption is only 1/10 of the traditional printing. Do not have to steam or re-baking after printing, can save a lot of water resources and reduce environmental pollution. But requires the use of a large number of transfer paper, these transfer paper is difficult to reuse after use.
Fifth, dyeing and finishing clean production technology, finishing process
After finishing the process can be implemented in the following measures to implement cleaner production: make full use of calendering, embossed, electro-optical, ginning, sanding, soft, pre-shrinking, velvet and other mechanical finishing. For example: the newly developed soft finishing technology, which is a variety of physical and mechanical effects, such as air conduction puffing, mechanical kneading and other means to beat together to process the fabric. After finishing the fabric feel soft and plump, smooth fluffy, vibrant structure. Reduced use of chemicals in processing, making the fabric fiber damage to reduce the human body and reduce environmental damage. By physical and chemical methods, such as low-temperature plasma treatment, can be reduced soft, improve moisture absorption and synthetic fiber antistatic, improve fiber luster, increase fiber cohesion and other effects. The use of biological enzymes for cellulose fiber and protein fiber textile polishing, soft finishing, as well as ramie and other textile improvement of itching and so on.
Dyeing and finishing is the dyeing and finishing fluid through the foam, made of foam system applied to the fabric after a low to the liquid dyeing and finishing process. Foam processing can improve production efficiency, reduce waste water and reduce the consumption of chemicals. In the textile finishing water repellent, oil repellent, hydrophilic, soft, flame retardant and other processing, the use of foam technology can be very good results, and can reduce energy consumption, while reducing environmental pollution.
As China's printing and dyeing industry clean production started late, accumulated little experience in the process of promoting the inevitable emergence of a variety of problems. But we should believe that with the continuous promotion of cleaner production, the continuous enrichment of experience, these problems will be solved.