Heat treatment → water washing.
In order to ensure that the new pretreatment process with high efficiency and short flow can achieve high efficiency and high quality, it is necessary to highlight three aspects: "high, hot and clean". That is, the padding working liquid should be fully absorbed and the liquid content should be high to ensure that there are enough reactive substances on the treated fabric; After pad-stacking, there should be a heat treatment process before washing to ensure that a large number of residual auxiliaries on the fabric after pad-stacking can give full play (this is one of the keys to improve wool efficiency); The washing process should be sufficient to ensure the removal of impurities from the fabric. In order to ensure "high-temperature, clean", it is necessary to reasonably design the composition of working fluid, appropriately increase the concentration of hydrogen peroxide and caustic soda, optimize the penetrant, training aid and stabilizer suitable for the new process, and improve and perfect the equipment. In recent years, great progress has been made in the development of high-efficiency short-flow pretreatment equipment at home and abroad, and many kinds of equipment suitable for high-efficiency short-flow pretreatment have appeared. The main equipment is introduced as follows:
(I) Liquid supply device At present, high-efficiency and short-process equipment mostly adopts high liquid supply and liquid supply through the core, especially through the core. There are mainly roller pressing method, vacuum pressing method and steam heating method to drive out air, among which vacuum pressing method has better effect. For example, the Flex-NiP high liquid supply device of Kusters company in Germany, the PiP-Sat device of Goller company in Germany, the Optimax high liquid supply device of MenZel company in Germany, and the JLMA41160 ~ 320 steam degassing impregnator produced by printing and dyeing machinery factory in China.
(II) Steam steaming equipment Steam steaming equipment needs a particularly long preheating time and a large amount of liquid, such as Hi-Cellent pretreatment high-efficiency steam steaming equipment in Wakayama, Japan, and high-efficiency steam steaming equipment matched with Flex-Nip high-efficiency liquid supply device in Kiosters, Germany.
(3) Water washing equipment The key point of water washing equipment is to grasp how to reduce energy consumption and improve water washing efficiency. The main forms are:
1. High-efficiency washing machine The high-efficiency washing equipment developed by foreign companies basically adopts a straight guide roller curve route, and the upper guide roller actively pressurizes to ensure that the fabric runs without tension and wrinkles, and the low water level reverses one by one. There are also filtration devices that don't adopt the arc cloth-threading route, and the spacing between the upper and lower guide rollers is less than 1000mm, and low-humidity rollers such as tax rollers and tractors are adopted, and the box body is sealed; At the same time, after adding the rubber pressing roller on the upper guide roller, the dirty liquid can be prevented from being carried from the front compartment to the back compartment of the liquid tank, and the concentration gradient of the washing liquid in the compartment is increased, thus improving the washing effect. For example, BEN-EXTRAC efficient washing machine developed by Swiss Berninge Company.
2. Powerful washing machine In recent years, a newly designed washing equipment-washing machine has appeared at home and abroad. Two groups of slits are connected in series to form a "door" shape, and several groups of water nozzles are arranged on the stroke of the slits. Steam and circulating hot water spray and collide in the slit, forming strong turbulence. The fabric passes through the high turbulence slit with the temperature of 100℃, and after countless washes, good washing effect can be obtained in a few seconds. For example, BEN-INJECTA washing machine developed by BENNINGET Company in Switzerland, and MH583A powerful washing machine developed by printing and dyeing machinery No.1 Factory in Zhangjiagang.
With the cancellation of textile export quota in 2005, new green fortresses will inevitably be added. In addition, the printing and dyeing industry is a big energy consumer, and energy shortage is another big problem that puzzles enterprises. Therefore, the pretreatment process is bound to develop in the direction of environmental protection, energy saving and water saving: low alkali pretreatment, such as using efficient scouring agent treatment technology; Biological enzyme pretreatment, such as pectinase, scouring enzyme, protease, amylase, peroxidase and various enzyme scouring processes; Low temperature pretreatment, such as cold pad-batch pretreatment process;
Efficient short process pretreatment
, such as one-step processing; Pretreatment of "green" scouring agents and auxiliaries, such as hydrogen peroxide bleaching or scouring "chlorine-free bleaching" process; Anhydrous or non-aqueous pretreatment, such as minimum bath ratio or foam bath scouring process.