A kind of reactive dyeing wastewater treatment method and concentrated liquid color paste

Abstract

The present application discloses a reactive dyeing wastewater treatment method and concentrated liquid color paste. The reactive dyeing wastewater treatment method includes the following steps: nanofiltering the reactive dyeing wastewater to be treated to retain the inactivated hydrolyzate in the reactive dyeing wastewater to form Circulating liquid and salt-containing liquid separated from each other, and the operating pressure during nanofiltration is 2-10 Bar; low-pressure reverse osmosis membrane is used to treat the circulating liquid to obtain a concentrated liquid color paste with a dye concentration of 10-20%, wherein The operating pressure is less than 40Bar; the saline solution is filtered by a high-pressure reverse osmosis membrane to form high-salt solution and pure water separated from each other, wherein the operating pressure is 100-120Bar.

Description

technical field [0001] The invention relates to the field of waste water treatment, in particular to a method for treating reactive dyeing waste water and concentrated liquid color paste. Background technique [0002] Dyeing with traditional reactive dyes needs to add a large amount of inorganic salts (sodium chloride or sodium sulfate) to promote dyeing, and commercial reactive dyes themselves also contain a large amount of inorganic salts (sodium chloride, sodium sulfate, calcium chloride and calcium sulfate, etc.), so Dyeing wastewater contains undyed reactive dyes and hydrolyzates and a large amount of inorganic salts. When treating wastewater, decolorization and desalination are required to meet discharge standards. However, the treatment cost of the current dyeing wastewater is high. Although the low-salt and salt-free dyeing process of reactive dyes is becoming more and more mature, the cost of reactive dyes and alternative salts suitable for this process is very hi...

AI Technical Summary

Problems solved by technology

Patent CN 104609605B discloses a process for membrane separation of printing and dyeing wastewater, but the dye recovered by nanofiltration according to this process is greatly reduced in activity due to hydrolysis and cannot be reused for dyeing textile fabrics; and the conductivity of the effluent obtained through this process is Only one-third of the input, two-thirds of the salt and most of the dyes are left in the nanofiltration concentrate, and the effective separation of dyes and inorganic salts has not been achieved.

[0006] Although the patent CN 105776712A has realized the effective separation of polyvalent salts and monovalent salts, the dyestuff cannot be utilized as a resource because it is decolorized by activated carbon adsorption

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