Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method and system for distillation recycling of dimethyl formamide rectified residual liquid

A technology of dimethylformamide and distillation recovery, which is applied in the separation/purification of carboxylic acid amide, organic chemistry, etc., and can solve the problems of dry burning cracking on the surface of the heating body, cracking of dimethylformamide, and no actual investment from enterprises. Achieve the effects of increasing production capacity, uniform heating, and reducing coking

Active Publication Date: 2014-08-13
CECEP CLEAN TECH DEV CO LTD
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in actual operation, the raffinate is seriously coked during the distillation process, which leads to the frequent shutdown of the system to clean up the coke or overhaul the equipment; if the coking is severe, the surface of the heating body may even crack due to dry burning, resulting in high equipment maintenance costs and low production efficiency; In addition, in the distillation process, dimethylformamide is often cracked due to improper distillation conditions.
Therefore, when the dimethylformamide in the rectification raffinate of dimethylformamide is recovered by conventional distillation methods, the overall economic benefits are poor, and generally no enterprises actually put it into operation

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 and system for distillation recycling of dimethyl formamide rectified residual liquid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0053] The rectification raffinate of dimethylformamide treated in Example 1 is produced in the production of polyurethane synthetic leather by wet process, wherein the content of dimethylformamide is about 22wt%, the water content is about 47wt%, and also contains a certain amount of Solid phase substances such as dander, resin, filler, etc.

[0054] Example 1

[0055] figure 1 It is a schematic diagram of recovering the rectification raffinate of dimethylformamide by distillation. like figure 1 As shown, the dimethyl formamide rectification raffinate enters the storage tank 1 with a heating jacket and agitator, and is stirred and heated to about 70°C in the storage tank to make it have good fluidity. The pump 21 is pumped into the filter 3 to filter out the solid phase matter, and enter the dryer 4 through the first feed port 41 of the dryer 4 under the action of gravity for distillation. The drier 4 is provided with a heating jacket and a stirrer (not shown), and the di...

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 method for distillation recycling of a dimethyl formamide residual liquid. The method includes the steps: allowing the dimethyl formamide rectified residual liquid to enter a dryer, controlling the pressure intensity in the dryer to be 40-60 kPa and the temperature to be 180-200 DEG C, allowing a part of the residual liquid after distillation to return back into the dryer, mixing with a dimethyl formamide rectified residual liquid newly entering the dryer, and controlling the solid content of the mixed residual liquid to be 25-35 wt%; and successively carrying out condensation and gas-liquid separation on a gas-phase substance discharged from an exhaust port of the dryer, and thus obtaining a dimethyl formamide product. The invention also discloses a system for distillation recycling of the dimethyl formamide residual liquid. The method can effectively recycle dimethyl formamide in the dimethyl formamide rectified residual liquid, and besides, realizes harmless treatment of hazardous waste; and dimethyl formamide in the production process is not cracked, an equipment coking phenomenon is less, system running is safe and stable, and the production efficiency is high.

Description

technical field [0001] The invention relates to a method and a system for recovering dimethylformamide rectification raffinate by distillation. Background technique [0002] When wet manufacturing polyurethane (polyurethane, referred to as PU) synthetic leather, it is necessary to use dimethylformamide (abbreviated as DMF) as a solvent to dissolve the polyurethane resin to form a slurry, and the obtained slurry is impregnated and coated on the surface of the base fabric, and then water Washing removes dimethylformamide, resulting in dimethylformamide-containing wastewater. In order to avoid environmental pollution caused by wastewater containing dimethylformamide, it is necessary to recycle the dimethylformamide in the wastewater. [0003] The above-mentioned waste water containing dimethylformamide recovers dimethylformamide through a distillation recovery system. First, it passes through a dehydration tower to remove part of the water, and then enters a rectification towe...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07C233/03C07C231/24
Inventor 韩晓强刘东风李宗轩郑骥何新辉阎凤美刘朝阳张蕊王璐邵立华
Owner CECEP CLEAN TECH DEV CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com