Method for recovering dilute DMF in sucralose crystallization mother liquor wastewater

A crystallization mother liquor, sucralose technology, applied in the direction of organic chemistry, carboxylic acid amide separation/purification, etc., can solve the problems of sewage treatment system load increase, DMF loss, high treatment cost, etc., to save sewage treatment costs, reduce Difficulty, energy saving effect

Pending Publication Date: 2021-03-12
ANHUI JINGHE IND
View PDF5 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to solve the problem that after the sucralose crystallization mother liquor is layered to remove ethyl acetate, the remaining waste water (containing 3-4% DMF) is directly discharged outside. To solve the problem of high cost, a method for recovering dilute DMF in sucralose crystallization mother liquor wastewater is provided

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
  • Method for recovering dilute DMF in sucralose crystallization mother liquor wastewater
  • Method for recovering dilute DMF in sucralose crystallization mother liquor wastewater
  • Method for recovering dilute DMF in sucralose crystallization mother liquor wastewater

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] (1) Send 24 m³ of waste water (waste water after the crystallization mother liquor is stratified to remove ethyl acetate, 75°C, DMF 3.5%) into a membrane filter press for filtration to remove solid impurities in the waste water;

[0019] (2) Send the filtered wastewater (70°C) into the extraction tower at an amount of 9m³ / h, and add n-octanol to the extraction tower at an amount of 9m³ / h, mix well, let stand for 30min to separate layers, and separate layers The final water phase is directly sent to the sewage station, and the organic phase (7.5% water, 3.5% DMF, 87% n-octanol, and the remaining components are organic impurities) is sent to the middle tank;

[0020] (3) The organic phase in the middle tank is sent to the rectification tower at a volume of 9m³ / h for vacuum distillation. The bottom pressure of the rectification tower is controlled at -0.09MPa, the temperature is 106°C, and the top temperature of the rectification tower is at 92°C, reflux ratio at 0.8:1, 10...

Embodiment 2

[0022] (1) Send 20m³ of waste water (the waste water after the crystallization mother liquor is stratified to remove ethyl acetate, 65°C, DMF 3%) into the membrane filter press for filtration to remove solid impurities in the waste water;

[0023] (2) Send the filtered wastewater (60°C) into the extraction tower at an amount of 8.2m³ / h, and add n-octanol into the extraction tower at an amount of 8.2m³ / h, mix well, and let stand for 25 minutes to separate layers. The stratified water phase is directly sent to the sewage station, and the organic phase (8% water, 3% DMF, 87% n-octanol, and the remaining components are organic impurities) is sent to the middle tank;

[0024] (3) Send the organic phase in the middle tank to the rectification tower at an amount of 8.2m³ / h for vacuum distillation, control the bottom pressure of the rectification tower at -0.07MPa, the temperature at 102°C, and the top temperature of the rectification tower At 88°C, with a reflux ratio of 0.6:1, 10m³ ...

Embodiment 3

[0026] (1) Send 30m³ waste water (waste water after the crystallization mother liquor is stratified to remove ethyl acetate, 70°C, DMF 4%) into a membrane filter press for filtration to remove solid impurities in the waste water;

[0027] (2) Send the filtered waste water (65°C) into the extraction tower at an amount of 10m³ / h, and add n-octanol into the extraction tower at an amount of 10m³ / h, mix well, and let stand for 40 minutes to separate layers. The final water phase is directly sent to the sewage station, and the organic phase (7.8% water, 3.2% DMF, 87% n-octanol, and the remaining components are organic impurities) is sent to the middle tank;

[0028] (3) Send the organic phase in the middle tank to the rectification tower at a rate of 10m³ / h for vacuum distillation, control the bottom pressure of the rectification tower at -0.05MPa, the temperature at 110°C, and the top temperature of the rectification tower at 96°C, reflux ratio at 1:1, 10m³ (including DMF11%) from ...

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 relates to a method for recovering dilute DMF in sucralose crystallization mother liquor wastewater. The method is characterized by comprising the following steps of: (1) feeding the wastewater into a membrane filter press for filtering to remove solid impurities; (2) sending the filtered wastewater into an extraction tower at the speed of 8-10m<3> / h, adding n-octyl alcohol into theextraction tower at the speed of 8-10m<3> / h, fully mixing, standing for layering, directly sending a water phase out to a sewage station after layering, and sending an organic phase into an intermediate tank; and (3) sending the organic phase into a rectifying tower at the speed of 8-10m<3> / h for reduced pressure distillation, controlling the tower bottom pressure of the rectifying tower at -0.09--0.1 MPa, the temperature at 101-111DEG C, the tower top temperature of the rectifying tower at 87-97 DEG C and the reflux ratio at 0.6-1: 1, sending tower top products to a recovery section, and making the n-octyl alcohol extracted from the tower bottom heat exchanged with and the rectifying tower feed organic phase and then, sent to an extraction front section middle groove, and applying the n-octyl alcohol to the extracting tower. The method has the beneficial effects that high-temperature wastewater can be directly utilized for extraction, so that energy consumption is reduced; 3-4% of DMFin the wastewater is enriched into 9-11% of DMF, and 10t / d of DMF can be stably recovered.

Description

technical field [0001] The invention belongs to the field of food additive production and relates to a method for recovering dilute DMF in sucralose crystallization mother liquor wastewater. Background technique [0002] In the production of sucralose, decolorization and crystallization are carried out after the neutralization solution is concentrated and dried. The mother liquor produced during the crystallization process contains ethyl acetate and waste water. After the mother liquor is statically layered to remove ethyl acetate, the waste water also contains Low concentration (3-4%) of DMF. In current production, about 300m³ of this waste water is produced every day. The existing treatment method is to discharge this part of the waste water directly. When the sewage is treated, the loss of DMF is 9-12 tons per day; and DMF is stable in nature and poor in biodegradability. , It is easy to kill the colony, and a large amount of DMF is used in the sewage treatment system, w...

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): C07C231/24C07C233/03
CPCC07C231/24C07C233/03
Inventor 郑学连徐立武颜作标
Owner ANHUI JINGHE IND
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