Separating method of aqueous alkali and size in refining waste water of dyeing and finishing

Abstract

A separating method of aqueous alkali and size in refining waste water of dyeing and finishing relates to separating treatment process technology of textile dyeing and finishing refining waste water. Alkali is added in the refining waste water, alkali concentration in the refining waste water is increased, and micro-molecular size coagulates by itself to form macro molecules and then is filtered through a nanometer filter. No other chemical drug is used during filtering, only a part of size and refining auxiliaries are left in filtrate, and the filtrate can be recycled in refining continuously. No flocculant or other chemical substances are required to be used, the size in the waste water is separated by using the principles, and an effect of recycling the separated alkali solution and auxiliaries is achieved.

Description

technical field [0001] The invention relates to the technical field of textiles, in particular to the separation and treatment technology of printing and dyeing scouring wastewater. Background technique [0002] In order to prevent the warp thread from breaking during the weaving process, the warp thread generally needs to go through a sizing process during the production of spun gray fabrics. In the sizing process, different sizing materials will be used according to the type of fiber. The commonly used sizing materials include starch, PVA (also called polyvinyl alcohol) and polymethyl acrylate, etc. [0003] However, in the printing and dyeing process, the slurry on the gray cloth must be completely removed before the dyeing process can be carried out. The process of removing the slurry is called pretreatment or scouring. In the current pretreatment or scouring process, not only the desizing treatment is carried out in the alkaline solution, but also other auxiliary agent...

AI Technical Summary

Problems solved by technology

[0006] 1. The flocculation effect is affected by temperature: the hydrolysis of the coagulant is mostly an exothermic reaction. When the water temperature is low, the hydrolysis of the coagulant is incomplete; when the water temperature is low, the Brownian motion is weakened, the viscosity increases, and the number of collisions is reduced. At the same time, High shear force is difficult to form larger flocs

[0007] 2. The flocculation effect is affected by the pH value of the water body: Since the pH value of the water body affects the form and performance of the coagulant aluminum salt and iron salt hydrolyzate, it has an impact on the coagulation effect

The greater the degree of polymerization of the inorganic polymer flocculant, the stronger its electrical neutralization ability and adsorption bridging function. For organic flocculants, except that the degree of polymerization, that is, the molecular weight is required to be greater than 10,000 Daltons, the flocculation of linear structure The flocculation effect of the agent is large, and the flocculation effect of the organic polymer flocculant with a ring-shaped branched chain structure is poor.

[0009] 4. The flocculation effect is affected by the dosage of flocculant: in water supply and wastewater treatment, the dosage of flocculant is an important control factor affecting the flocculation process. The optimal dosage, the flocculation effect will decrease when it is lower or more than this dosage

[0012] In addition, the disadvantages of using flocculation and separation methods to treat refining sewage: due to the large amount of chemical input, high cost of dosing, incomplete removal of dirt, large amount of sludge and high water content, and difficult dehydration, it is difficult to further process, resulting in Secondary pollution