Combined treatment method for two kinds of waste acid water generated in tetraacetylethylenediamine (TAED) production

A technology of tetraacetylethylenediamine and combined treatment, applied in water/sewage multi-stage treatment, water/sludge/sewage treatment, chemical instruments and methods, etc., can solve the problems of high steam energy consumption and complicated on-site operation, etc. Achieve the effect of avoiding solid waste, being conducive to environmental protection and saving energy

Active Publication Date: 2012-07-18
浙江金科日化新材料股份有限公司
View PDF5 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Chinese patent CN101492362A discloses a technology for producing sodium acetate trihydrate by using waste acetic acid water. The technology involves atmospheric distillation, neutralization of condensed acid water after distillation, decolorization of neutralization solution, and crystallization products. The steam energy consumption of this process is relatively high

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Combined treatment method for two kinds of waste acid water generated in tetraacetylethylenediamine (TAED) production

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] Such as figure 1 as shown,

[0031] 1. The dark waste acid water with an acetic acid content of 10% passes through the heat exchanger 1, and enters the reboiler 2, and uses 0.7MPa raw steam to heat the dark waste acid water. The flow rate of the raw steam is 1.1t / h. Acid vapor 130°C.

[0032] 2. The acid vapor exchanges heat with the neutralizing liquid entering the first effect in the first-effect heat exchanger 3. After the acid vapor condenses, it passes through the pressure liquid-sealed pipe, and the condensed acid water enters the reboiler dark waste acid water in the heat exchanger 1 pair. Preheating, after heat exchange, the condensed acid water enters the light-colored acid water tank 9, and mixes with the light-colored acid water with 20% acetic acid content.

[0033] 3. The mixed acid water is neutralized with soda ash in the neutralization kettle 10, the end-point Ph value is 7.5, and the temperature is 40°C.

[0034] 4. Add 0.1% thiourea dioxide to the n...

Embodiment 2

[0045] 1. The dark waste acid water with an acetic acid content of 10% passes through the heat exchanger 1 and then enters the reboiler 2. The dark waste acid water is heated by 0.4MPa raw steam, and the flow rate of the raw steam is 1.1t / h. Acid vapor 110°C.

[0046] 2. The acid vapor exchanges heat with the neutralizing liquid entering the first effect in the first-effect heat exchanger 3. After the acid vapor condenses, it passes through the pressure liquid-sealed pipe, and the condensed acid water enters the reboiler dark waste acid water in the heat exchanger 1 pair. Preheating, after heat exchange, the condensed acid water enters the light-colored acid water tank 9, and mixes with the light-colored acid water with 20% acetic acid content.

[0047] 3. The mixed acid water is neutralized with soda ash in the neutralization kettle 10, the end-point Ph value is 10.5, and the temperature is 80°C.

[0048] 4. Add 0.02% thiourea dioxide to the neutralizing solution and stir fo...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a combined treatment method for two kinds of waste acid water generated in tetraacetylethylenediamine (TAED) production. The combined treatment method is characterized by comprising the following steps of: evaporating dark acid water generated after washing TAED crystals by using live steam; carrying out multi-effect concentration on decolored neutralized liquid by using the acid steam generated by evaporation as a heat source; cooling and crystallizing; and separating solid from liquid to obtain sodium acetate trihydrate which is a by-product, wherein the live steam can be generated by burning residues for recycling after the dark acid water is evaporated, The decolored neutralized liquid is generated by the method that after the acid steam is subjected to heat exchange, the acid steam is condensed into colorless acid water; then the colorless acid water is mixed with light acid water generated by high-temperature dewatering after acetic acid and ethanediaminereact in the production of the TAED; alkali is added to the mixed liquid for neutralization; and then the mixed liquid is decolored by using thiourea dioxide. According to the combined treatment method, the acid steam of the dark acid water is used as a primary heat source for carrying out the multi-effect concentration on the mixed liquid of the mixed acid, therefore, energy can be greatly saved, and environment friendliness is facilitated; and the thiourea dioxide is used as a decoloring agent, the complication of solid and liquid separation and the generation of solid waste residues, whichare brought by decoloring solid adsorptive substances such as activated carbon, are also avoided.

Description

technical field [0001] The invention belongs to the technical field of waste water treatment, and in particular relates to a method for combined treatment of two different waste acid waters produced in the production process of tetraacetylethylenediamine. Background technique [0002] As an effective bleach activator, tetraacetylethylenediamine (TAED) has excellent low-temperature bleaching performance and good environmental protection, and is currently widely used in domestic and foreign washing industries. [0003] Generally, tetraacetylethylenediamine is diacylated by excess acetic acid and ethylenediamine, dehydrated at high temperature to generate diacetylethylenediamine, and then synthesized by tetraacylation of acetic anhydride and diacetylethylenediamine. After synthesis, TAED is crystallized, filtered, After washing, drying, granulation and packaging, it becomes a finished product. After diacylation, high-temperature dehydration produces a light-colored acid water ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C02F9/10C07C53/10C07C51/41
Inventor 施孟华魏一帆章金龙连培祥
Owner 浙江金科日化新材料股份有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products