Industry formaldehyde waste water treatment and recycling recovery process thereof

A formaldehyde waste water recycling technology, applied in the chemical industry, heating water/sewage treatment, water/sewage multi-stage treatment, etc., to achieve good separation effect, large processing capacity, and efficient recovery

Inactive Publication Date: 2009-12-09
NANJING UNIV
View PDF0 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] Aiming at the problems existing in the existing formaldehyde wastewater treatment process, the present invention proposes a process for the treatment and resource recovery of industrial formaldehyde wastewater. Specifically, it uses formaldehyde and methanol to react under the action of a catalyst to form methylal, and uses a rectification tower to carry out Two separations, and finally get the reaction product methylal and the waste water up to the standard, and the excess methanol in the system can be recycled

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
  • Industry formaldehyde waste water treatment and recycling recovery process thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0032] Example 1: Treatment of 1% formaldehyde wastewater and resource utilization of formaldehyde

[0033] The composition of formaldehyde wastewater is 1% formaldehyde mass concentration, and the rest is water. The wastewater stream feeds 8000Kg at one time, and the temperature reaches 70-75°C after heat exchange. According to the ratio of the amount of alcohol and aldehyde substances to 20, 1700Kg of 95% industrial methanol is fed at one time, and the temperature of methanol reaches 60-65°C after heat exchange. ℃, while adding 320Kg of strongly acidic cation exchange resin (provided by Jiangsu Yonghua Fine Chemicals Co., Ltd., the same below) with 4% of the quality of waste water to be treated as a catalyst, controlling the temperature of the reactor to 70-80 ℃, and the situation of stirring speed 200r / min The reaction was carried out for 30 minutes. After the reaction was completed, the valve V3 was opened, and the waste water system entered the storage tank 7.

[0034]Th...

Embodiment 2

[0036] Example 2: Treatment of 5% formaldehyde wastewater and resource utilization of formaldehyde

[0037] The composition of formaldehyde wastewater is 5% formaldehyde mass concentration, and the rest is water. The wastewater stream is fed 6000Kg at one time, and the temperature reaches 70-75°C after heat exchange. According to the aldol ratio of 10, 3200Kg of 95% industrial methanol is fed at one time, and the temperature of methanol reaches 60-65°C after heat exchange. Treat 120Kg of strongly acidic cation exchange resin with 2% of the mass of wastewater as a catalyst, control the temperature of the reactor at 65-75°C, and react for 30 minutes at a stirring speed of 200r / min. After the reaction is completed, open the valve V3, and the wastewater system enters the storage tank.

[0038] With the operation of the primary rectification tower of embodiment 1, the formaldehyde concentration monitoring in the tower still of the primary rectification tower is 0.2%, and the up-to-...

Embodiment 3

[0039] Example 3: Treatment of 5% formaldehyde wastewater and formaldehyde resource utilization (2)

[0040] On the basis of Example 2, feed 1600Kg of 95% industrial methanol at one time according to the aldol ratio of 5, and adjust the temperature of the reactor at 70-80°C and other reaction conditions remain unchanged, and operate with the first-stage rectifying tower of Example 2 , the concentration of formaldehyde in the waste water in the bottom of the primary distillation tower is monitored as 0.5%, which fails to reach the standard. The measures taken are to enter the feed port of the formaldehyde waste water through the valve V9 and the pump, and the waste water outflow of the bottom of the tower is 7720Kg / h. The outflow of methanol and methylal mixed liquid at the top of the primary rectification tower is 2280Kg / h; % of methylal, its output is 910Kg / h, and the secondary rectification tower bottom obtains 1370Kg / h methanol through valve V8 and pump reflux circulation t...

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 uses formaldehyde and excessive methanol to react and produce methylal under the effect of catalyst, then uses a rectification column to carry out separation twice to obtain the methylal with high purity reaction product and up-to-standard waste water in which the excessive methanol can be recycled. Compared with other conversion methods and high pressure distillation in literature documents, the industry formaldehyde waste water treatment and recycling recovery process thereof in the invention has the advantages that: (1) efficient recovery is realized, high grade methylal is obtained, and the aim of treating waste water is realized; (2) the process in the reaction stage is intermittent and is continuous in the separation stage, so that the process features large processing capability and high energy efficiency; (3) coupling usage, energy saving and consumption reducing of heat can be realized.

Description

technical field [0001] The invention relates to a treatment and recycling process of industrial formaldehyde waste water. Background technique [0002] Formaldehyde is an important chemical raw material, mainly used in plastics industry (such as phenolic resin, urea-formaldehyde resin, etc.), synthetic fiber, synthetic rubber, pharmaceutical intermediates, dyes and paints and other industries. The concentration of formaldehyde used in industry is generally 37%, and formaldehyde has high reactivity only in aqueous solution. Even if solid formaldehyde is used as raw material, most of its reactions are required to be carried out in aqueous solution, so in the industrial production process A certain concentration of industrial formaldehyde wastewater will inevitably be produced in the environment. Formaldehyde is highly toxic to humans and warm-blooded animals. It can irritate the skin, easily cause dermatitis, and produce respiratory tract irritation, allergies, abnormal liver...

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): C02F9/10C07C43/30C07C41/58B01D3/00C02F1/04C02F101/34
CPCY02P20/10
Inventor 张志炳李磊邹海郭亚红
Owner NANJING UNIV
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap