Important technical innovation in printing and dyeing industry

　　Recently, vital song researcher, tianjin institute of industrial biology, Chinese academy of sciences, has developed a bio-textile enzyme technology, which replaces caustic soda in the pretreatment of printing and dyeing materials, will greatly reduce waste water emissions, save water and electricity, and has been evaluated by the industry as another important technological innovation in China's printing and dyeing industry.

　　Have you ever thought about the circumstances in which a T-shirt, jeans, or dress you wear is made? As a matter of fact, colorful clothes bring great damage to the environment. The printing and dyeing industry has always been a representative of the backward production capacity with high pollution and high energy consumption. In recent years, many local printing and dyeing industries, especially those in first-tier cities, have been gradually moved out or even closed down.

　　At the same time, printing and dyeing are an indispensable link in the textile industry. Under the pressure of policies, the printing and dyeing industry is constantly seeking technological innovation and moving towards the direction of green printing and dyeing.

　　The biotechnology, developed by vital song, a researcher from tianjin institute of industrial biology, Chinese academy of sciences, which replaces caustic soda in the pretreatment of printing and dyeing materials, can greatly reduce the discharge of wastewater, save water and electricity, and has been evaluated by the industry as another important technological innovation in China's printing and dyeing industry.

　　The printing and dyeing industry urgently needs to fight pollution"The current pollution problem in China's textile industry has reached a point where it is urgent to solve it. Traditional textile production not only brings pollution to the environment, but also produces all kinds of harmful chemicals, causing harm to our health. The whole society should jointly resist the polluting and consumptive production process ""There are at least 8,000 chemicals in the world that use 25 per cent of pesticides to grow non-organic cotton in the process of turning raw materials into textiles," according to data released by the Earth Pledge. This will lead to irreversible damage to humans and the environment, and two-thirds of the carbon emissions will continue after clothing is purchased. It takes dozens of gallons of water to process fabric, especially fabric dyeing, which requires 2.4 trillion gallons of water.

　　China's environmental statistics show that the textile industry is a major polluter in key industries. The discharge of textile industrial wastewater ranks among the top among the 41 industries in China, and the discharge of printing and dyeing process accounts for more than 70% of the discharge of textile wastewater.

　　In addition, as an important source of water pollution, China's textile industry also consumes a huge amount of water resources, far behind the rest of the world in terms of water utilization efficiency. According to the report on prevention and control of industrial pollution in key industries published by China environmental science press, the average pollutant content in China's printing and dyeing wastewater is 2-3 times higher than that of foreign countries, and the water consumption is as high as 3-4 times. At the same time, printing and dyeing wastewater is not only the main pollutant in the industry, but also the sludge produced by printing and dyeing wastewater has some problems in the treatment.

　　Among them, the pollution caused by the use of large amounts of caustic soda in the pretreatment of printing and dyeing materials is particularly serious. "You have to treat it with caustic soda, steam it hard, and then neutralize it with hydrochloric acid, which is a lot of waste water." Said the manager who had worked in the printing and dyeing industry for many years.

　　To address this situation, a team led by song vital, a researcher at the tianjin institute of industrial biotechnology under the Chinese academy of sciences, first targeted the development of new enzyme preparations that could replace caustic soda.

　　Biological enzyme preparation solves the problem of printing and dyeingThe traditional pre-printing and dyeing process consists of five steps: burning, desizing, refining, bleaching and silking. Although some foreign companies used to produce enzyme preparation before printing and dyeing, but only used in the process of desizing.

　　Song Hui said, enzyme preparation is a kind of high efficiency, low consumption, non-toxic biological catalyst, biological treatment based on enzyme preparation method is to solve the printing and dyeing industry the ideal way to high pollution and high consumption, but, after the varieties of enzyme preparation, single higher cost of enzyme preparation of compound and a lack of compatibility with textile auxiliaries research, complete dye enzymatic pretreatment process has not yet formed.

　　This time, song vital's team and a number of companies have reached close cooperation. After three years, they have developed a variety of high-quality textile bioenzyme preparations and their production processes, including amylase, alkaline pectinase, xylanase and catalase.

　　"Desizing - refining compound enzyme preparation has solved the difficult problem of desizing polyester cotton and pure polyester grey cloth. In the past, amylase desizing could only solve the grey cloth with starch sizing, and the grey cloth with PVA mixture could only be boiled and removed with high temperature alkali. Days spinning group chief engineer Ding Xueqin said, compounds containing flame retardant silk, polyester fabric varieties of high temperature alkali cooking desizing, otherwise it will shrink, and the use of biological compound enzyme desizing effect is very good, to prevent the fabric shrinkage, remission and starch, PVA and clean, and after processing cloth feel fluffy and soft, also solves a technical problem for the factory.

　　Save water and electricity and reduce sewage dischargeAccording to song vital, once the enzymatic desizing and refining process is completed, it not only saves the high temperature of the traditional treatment process, but also reduces the amount of steam used in the pretreatment process at a low temperature, significantly saving the steam energy consumption. Compared with the traditional process, it saves 25 to 50 percent of steam and 40 percent of electricity.

　　Enzymatic pretreatment process replacing traditional technology of caustic soda desizing and caustic soda refining process, alternative means that biological fermentation product caustic soda, refining agent and other chemicals, therefore, can greatly reduce the processing wastewater pH value and COD value, the chemical agents such as effectively replace the refining agent can make in pretreatment wastewater COD value will be reduced by more than 60%.

　　"Biocomposite enzyme preparation has the characteristics of mild treatment conditions, high efficiency and good specificity. The application of bioenzyme treatment has little damage to cotton fiber, and it has an efficient degradation effect on starch slurry and PVA slurry on grey cloth, which can achieve good desizing effect." The quality of cotton fiber treated with this technology is much higher than that of traditional methods, song said.

　　Regarding the price issue concerned by printing and dyeing enterprises, song vital said that the biocomposite enzyme activity efficiency is high, the dosage is low, the price is the same as the general textile auxiliaries, will not increase the processing cost, most textile enterprises can accept it. In addition, the application of biological enzymes for pretreatment can significantly reduce the cost of pretreatment and improve the economic benefits of the textile industry by reducing the energy consumption of steam, eliminating the cost of alkaline wastewater treatment, and reducing the amount of various chemical AIDS.

　　"In the application of enzymatic pretreatment technology of tianfang, the enzymatic pretreatment of 12,000 meters pure cotton cotton cloth and 11,000 meters aramid hot-wave cabb can reduce the cost by 30% and 70% respectively compared with the traditional alkaline process." "Said ding.