How to solve the problem of excessive ammonia nitrogen emission in reactive printing production?

In reactive dye printing, due to the excessive amount of urea, the ammonia nitrogen content in sewage often exceeds the standard, but urea is an indispensable auxiliary. As a hygroscopic agent, the moisture absorption can reach 24.4%. At the same time, it is also a co-solvent, used to modulate dyes, help dissolve and stabilize color paste. Its main effects on reactive dyes are as follows: (1) Although there are hydrophilic sulfonic acid groups in reactive dye molecules, it has good solubility, but due to the high amount of dyes used in printing pulping, And the liquor ratio is small, so urea still needs to be used to help dissolve. (2) When the reactive dyes are heat-set after printing, urea promotes fiber expansion through moisture absorption, which is beneficial to the penetration of dyes and increases the moisture absorption. The color effect of thermosetting reactive dyes is more remarkable. (3) It is the water retention agent in the color paste. Generally, the minimum amount of urea is 1%. When the amount of dye exceeds 1%, the amount of urea is equal to that of dye, or an increase of 3%-5%.

Therefore, in order to meet the requirements of environmental protection and reduce the pressure of sewage treatment in factories, the urea-substituting agent CY-391 can be used to partially or completely replace urea to reduce the emission of ammonia nitrogen.

Urea substitute CY-391

Specifications

Appearance        Colorless transparent liquid

pH value          (1% aqueous solution) 6-8

Sugar content (%)   about 35%

Performance and Features

1. It has the functions of hygroscopic, solubilizing and expanding fiber.

2. It can partially or completely replace urea for reactive printing of pure cotton and rayon fabrics, without affecting the color of the fabrics.

3. Can significantly reduce the ammonia nitrogen content of wastewater.

Scope of application

It is suitable for reactive printing of pure cotton and rayon fabrics.

Instructions

Process formula:

Dyes: The amount remains the same

Slurry: The dosage of each component remains unchanged except for urea

Urea: according to the amount of urea substitute CY-391

CY-391: It can replace all urea, and can also be mixed with urea in different ratios of 1:1, 1:2, etc.

Please adjust the specific dosage according to the fabric requirements and processing conditions.