Namely, it is welded, white, mercerized, printed and painted. Then there are some finishing processes, which help to increase the resistance to wrinkling, achieve dimensional stability, a certain opacity, hydrophobic ties, etc. Thus, to make cotton waterproof it is processed with aluminum acetate or formate mixed with dispersed wax. In order to protect it from burning, it is treated with titanium or zirconium salts.The largest amount of waste (65%) is separated during the washing, boiling, dyeing and finishing processes.
When processing wool, waste originates from the processes: cleaning, dyeing, frosting, filling, carbonizing and washing. In fact, all natural impurities are removed by immersing the wool into a hot alkaline detergent. Wools containing large amounts of impurities are cleaned with an organic solvent by extraction, and then the solvent is regenerated by distillation. Colouring is done with a warm colour solution, circulating through the wool, and the lubrication is done by spraying the wool with oil mixed with water. Its quantity is from 1% to 11% relative to the mass of the wool, and the task is to increase
cohesion between the fibers and facilitate the spinning. In the final processes of processing the wool, the entire oil is removed. For carbonization, a hot solution of concentrated acid is used in order to transfer the plant material into the wool into free carbonated particles, which are then mechanically removed from the fabric by processing it on special machines. Following these processes, staining,
whitening and stirring are followed in order to achieve certain properties.
When cleaning the wool, as well as the finishing operations, a brown coloured, coloured effluent with a pH value of 9 to 10.5 is obtained, which is characterized by high values of BPK5 (900 mg / L), high content of total waste (3000 mg / L) and contains chromium (4 mg / L). The main source for the increased values of BPK5 are wool grease, which are released during cleaning and soap used for washing. For 1t wool it takes 600t water. The largest amount of BPK5 (75%) comes from washing and filling the hairs, then from the bleaching process (25%), and the smallest amount (1%) is from the neutralization process after carbonization of the wool.
The synthetic fibers from which the fabric is made are composed of pure chemical compounds and do not contain natural impurities like wool and cotton. Therefore, they require slight cleaning and bleaching before their staining. The most commonly used synthetic fibers are: viscose, nylon, cellulose, travare, dacron, orlon, perlon etc. Viscose is obtained from cellulose. The nylon and the perlon are polyamide fibers, and the weed is a polyester fiber which in Macedonia was produced in "Hemтекст" under the name Maklen. The eagle is a polyacrylonitrile fiber, and "Ohis" produces it under the name Malon. The semantics of the treatment of these fibers are mainly derived from the chemicals used in the process of dyeing and cleaning.
Erasmus+ 46