The Recycle Dyeing With Dip Dyeing Effluent Of High-Temperature Reactive Dye On Cotton Yarn For Dark Colour

Cotton yarn dyeing has a certain proportion in our country's textile printing and dyeing manufacturing, and a lot of cotton yarn is dyed with high-temperature reactive dye. The effluent of the reactive dye contains lots of salt and alkali, and also some unhydrolyzed reactive dye. If the effluent was discharged, it will cause a great burden to the sewage treatment; whereas, if we can reuse the dip dyeing effluent, then we can reuse the salt, alkali, dye and water in it and decrease the sewage discharge with the purpose of utilizing the resource circularly, then can truly realize energy conservation, consumption reduction, water saving and discharge reduction.This article optimized the dyeing-fixing one-bath-one-step dyeing process (one step process for short) of the selected reactive dyes respectively, and got their best one-step dyeing conditions. Through comparing the dyeing effects of one-step process with traditional two-step dyeing process and found that their dyeing effects were almost the same, laying a foundation for further research on this subject. This article researched the relationship between the dye and the K/S value of the dyed samples in low concentration, and the results indicates that there was good linear relationship between them, and we can use this relationship to calculate the amount of effective dye in the dip dyeing effluent. This article also researched the relationship between the pH value of the solution and the concentration of the alkali, the conductivity and the salt concentration in the solution, and then determined the concentration of the salt and alkali in the solution and the replenish amount of them when dyeing with dip dyeing effluent.After the determining of repleshment of dye, salt and alkali in the recycle dyeing process, this paper made the use of the reactive dye of A series and B series independently or three dye toning to dye cotton knitted fabric recycle, using dip dyeing effluent, the results showed that the color difference between the samples gained by recycle dyeing with dip dyeing effluent and the initial samples could reach to 4-5 level or above, the relevant color fastness was similar with the initial samples, this indicated that the recycle dyeing method with dip dyeing effluent was feasible. Then the dyeing of the reactive dye of A series and B series with three dye toning were applied to the dyeing of yarn, and the results of the experiment also confirm that this method was also applied to the dyeing of yarn.The recycle dyeing method of high temperature reactive dye using dip dyeing effluent can reduce the amount of dye and dyeing auxiliary, save water and reduce the discharge of wastewater, in addition, the one step dyeing process is simple and in line with the society's low-carbon economy development situation like energy conservation, consumption reduction, water saving and discharge reduction.