For a long time, the impression that printing and dyeing has given people does not seem to be very good, and environmentalists are even talking about it, thinking that this is an important source of air and water pollution from the textile industry. It is undeniable that the printing and dyeing process does produce waste gas and waste water, and bears an unshirkable responsibility for environmental pollution. On the other hand, if such problems are solved by modern textile technology, it will also promote economic construction while protecting the environment. Made a contribution. In order to promote cleaner production in the printing and dyeing industry, lowering the temperature of the pretreatment process and reducing the use of chemicals is an important way, and it will be an inevitable choice. The "Key Technology of Textile Low Temperature Pretreatment" jointly completed by Donghua University, Huafang Co., Ltd. and Qingdao Weilan Biological Group Co., Ltd. won the first prize of the 2013 Textile Light Technology Progress Award and became the focus of energy conservation and emission reduction in the printing and dyeing industry.
Detailed research finally achieved industrialization results
"The water consumption, energy consumption and CODCr emissions of the fabric pretreatment process accounted for 55% to 60% of the entire printing and dyeing process." , Cold-rolled reactor pre-treatment has matured and is applied industrially. Although this process is energy-saving, its chemical use and pollutant emissions are significantly higher than conventional processes, and it is not a clean production technology in the true sense.
According to Li Chunguang, Executive Director of the Technology Center of the Engineering Department of Huafang Co., Ltd., the use of organic activators to reduce H2O2 bleaching temperature is limited by factors such as the cost and efficiency of organic activators, and the technology has not been truly realized, both internationally and domestically. Industrial application. In this context, "Key Technologies for Low-Temperature Textile Pre-treatment" has successfully developed a series of pre-treatment processes for low-temperature and high-efficiency textile desizing, scouring and bleaching, which has truly realized the industrial application of low-temperature pre-treatment of grey fabrics according to quality and on demand.
The reason why low-temperature pretreatment technology can be industrialized is due to several major innovations of the project, namely the key technology for the synthesis of imitation enzyme catalyst ligands, the key technology for the synthesis of imitation enzyme catalysts, and the low-cost, high-alkali-resistant pectin. Development of key technologies for enzyme industrialization and fabric low-temperature series pre-treatment processes.
Mao Zhiping introduced several main contents in detail, "First, in view of the bottleneck problem of low-temperature bleaching efficiency and high cost of H2O2, we innovatively designed an efficient metal complex-like enzyme-like catalyst, developed its short-flow synthesis process, and achieved scale. Chemical production. Researched the organic activator-metal imitation enzyme catalyst compound synergistic technology, which improves the catalytic efficiency and significantly reduces the cost of the catalyst, which is less than 1/5 of the organic activator tetraacetyl ethylene diamine ".
Secondly, use targeted genetic modification technology to improve wild alkaline pectinase producing bacteria, construct alkaline pectinase engineering bacteria, improve the alkali resistance and H2O2 tolerance of pectinase, optimize fermentation process, and develop liquid enzyme activity protection Technology, took the lead in realizing the commercialization of liquid alkaline pectinase in China.
Finally, build a H2O2 catalysis-stability control system to precisely control the decomposition rate of H2O2 in the bleaching process; develop high-efficiency low-temperature dewaxing additives to improve the wool effect of low-temperature pretreatment fabrics; use alkaline pectinase and enzyme-like catalysts to develop series The low-temperature pretreatment process reduces the desizing and refining temperature to 35°C~40°C, and the bleaching temperature to 50°C, so that the fabric can be processed according to quality and on demand. The average unit product can save water by 10%, save energy by 35%, reduce CODCr emissions by more than 10%, and the effect of energy saving and emission reduction is remarkable.
Cleaner production re-established the vane
In the past few years when the project was promoted and applied, 5 promotion bases have been established and 9 demonstration lines have been built. From 2010 to 2012, 5 application companies have accumulated a total of 359.45 million yuan in new output value and 60.442 million yuan in new profits.
In terms of social and environmental benefits that the industry is paying attention to, its results are also remarkable. The project successfully realized the industrialization of textile biological enzyme desizing and scouring technology using domestic biological enzyme preparations. The desizing and scouring temperature was reduced to 40°C~80°C, the amount of alkalis was reduced by 90%, and the amount of surfactants was reduced by more than 50%. The imitation enzyme catalyst was introduced into the printing and dyeing industry, and the rapid low-temperature pretreatment of textiles was successfully realized, and the bleaching temperature of textiles was reduced from 100℃ to 50℃~80℃. The national cotton fabric processing volume is 30 billion meters per year. The technical achievements of the project are calculated at a promotion rate of 30%, which can reduce water consumption by 9 million tons per year, save 800,000 tons of standard coal per year, and reduce COD emissions by 2500 tons per year. The consumption of caustic soda is 27,000 tons/year.
How to truly realize cleaner production is the path that the printing and dyeing industry must explore to achieve healthy and sustainable development. The "key technology of textile low-temperature pretreatment" has set such an example. At the exchange meeting of scientific and technological achievements held by Huafang, experts and enterprises stated that this technology has broken through the large-scale mass production technology of alkaline pectinase and has promoted the progress of the biological enzyme preparation industry; it has broken through the low cost of imitation enzyme catalysts. Large-scale mass production technology promotes the application of high-efficiency catalysts in the printing and dyeing industry, and contributes to technological innovation in the printing and dyeing industry; it can significantly reduce the energy consumption of textile pretreatment and reduce COD emissions, which is of great significance to the promotion of energy saving, emission reduction and sustainable development of the printing and dyeing industry .