Extraction and dephenolization process of coal gasification wastewater

A coal gasification wastewater and extraction technology, applied in chemical instruments and methods, extraction water/sewage treatment, water/sewage multi-stage treatment, etc., can solve the problems of low extraction efficiency, low distribution coefficient, low extraction tower efficiency, etc., to achieve The technical process is simple, the distribution coefficient is high, and the effect of high dephenolization efficiency

Inactive Publication Date: 2006-09-20
SOUTH CHINA UNIV OF TECH
View PDF0 Cites 25 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

But for the extraction and dephenolation of high-concentration phenol-containing coal gasification, oil refining and coking wastewater, the main problems at present are: (1) the extraction efficiency of common extractants to alkaline phenol-containing wastewater and polyphenols is low; 2) The efficiency of the extraction tower is low; (3) The extraction equipment is easy to block, etc.
Diisopropyl ether has the advantages of low boiling point and saturated vapor pressure, low water solubility, easy recovery, low energy consumption, etc., but its dephenolization efficiency is low, especially for polyphenols
Not only the waste of phenol is caused, but also the waste water enters the subsequent biochemical treatment tank, which seriously exceeds the biochemical treatment load, and it is difficult to meet the sewage discharge index requirements, posing a serious threat to the water body of the lower reaches of the Songhua River
The extraction effect of diisopropyl ether on unit phenols can basically meet the requirements, but it is not a good extraction agent for polyphenols, and its distribution coefficient is very low
The distribution coefficient of diisopropyl ether to phenol is 36.5, but those of hydroquinone and pyroglucinol are only 1.03 and 0.18 respectively, which is not suitable as an extraction solvent for coal gasification wastewater containing polyphenols
However, the regeneration of TBP needs to use lye to neutralize the complexed extract, and the sodium salt of phenol is generated in the process. The subsequent treatment process for recovering phenol is complicated and difficult to apply to the situation where the amount of wastewater is large.
[0008] To sum up, the current extraction and dephenolization technology for high-concentration phenol-containing wastewater is not ideal, and the phenol concentration of the treated wastewater is still quite high, which is difficult to meet the standard discharge of subsequent biochemical treatment and seriously pollutes the surrounding environment

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] Select phenol-containing coal gasification wastewater to be treated, the treatment capacity is 100t / h, the phenol content is 3000mg / L, the volatile phenol content is 4000mg / L; the pH value is 5, COD Cr The value is 30000mg / L, the oil content is 200mg / L

[0037] (1) Mix the phenol-containing coal gasification wastewater with the extraction solvent methyl isobutyl ketone to obtain a mixed solution; the mixing uses a static mixer for parallel flow mixing, the temperature of the mixed solution is 30 ° C, and the phenol-containing coal gasification wastewater in the mixed solution The pH value is 11, and the volume ratio of the extraction solvent methyl isobutyl ketone to the phenol-containing coal gasification wastewater is 1:10.

[0038] (2) The mixed liquid is separated into phases to obtain a solvent phase and a residual liquid; the phase separation is carried out with an oil-water separator, and the residence time of the mixed liquid in the oil-water separator is 40 min...

Embodiment 2

[0044] Select phenol-containing coal gasification wastewater to be treated, the treatment capacity is 100t / h, the phenol content is 10000mg / L, the volatile phenol content is 1500mg / L; the pH value is 10.5, the COD Cr The value is 15000mg / L, the oil content is 500mg / L

[0045] (1) Mix the phenol-containing coal gasification wastewater with the extraction solvent methyl isobutyl ketone to obtain a mixed solution; the mixing uses a static mixer for parallel flow mixing, and the temperature of the mixed solution is 85 ° C, and the phenol-containing coal gasification wastewater in the mixed solution The pH value is 3, and the volume ratio of the extraction solvent methyl isobutyl ketone to the phenol-containing coal gasification wastewater is 10:1.

[0046] (2) The mixed liquid is separated into phases to obtain a solvent phase and a residual liquid; the phase separation is carried out with an oil-water separator, and the residence time of the mixed liquid in the oil-water separato...

Embodiment 3

[0052] Select the phenol-containing coal gasification wastewater to be treated, the treatment capacity is 100t / h, the phenol content is 5000mg / L, the volatile phenol content is 2500mg / L; the pH value is 6.5, the COD Cr The value is 25000mg / L, the oil content is 300mg / L

[0053] (1) Mix the phenol-containing coal gasification wastewater with the extraction solvent methyl isobutyl ketone to obtain a mixed solution; the mixing uses a static mixer for parallel flow mixing, and the temperature of the mixed solution is 45 ° C, and the phenol-containing coal gasification wastewater in the mixed solution The pH value is 8, and the volume ratio of the extraction solvent methyl isobutyl ketone to the phenol-containing coal gasification wastewater is 10:7.

[0054] (2) The mixed liquid is separated into phases to obtain a solvent phase and a residual liquid; the phase separation is carried out with an oil-water separator, and the residence time of the mixed liquid in the oil-water separa...

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

PropertyMeasurementUnit
chemical oxygen demand (mass)aaaaaaaaaa
Login to view more

Abstract

This invention discloses a method to remove high-concentration hydroxybenzenes from coal-gasification sewage, that is, coal-gasification sewage containing hydroxybenzenes and isobutyl methyl ketone as extracting solvent are mixed and separated so as to obtain solvent phase and remnant aqueous phase liquid. Solvent and crude hydroxybenzene are extracted from the solvent phase by distillation. Multiple-class reflux extraction is carried out towards remnant aqueous phase liquid and rudimental solvent is further extracted from the extract. Facilities involved in this method include a static mixer, an oil-water separator, a hydroxybenzene distillation tower and an extraction tower. Extracting coal-gasification sewage containing high-concentration hydroxybenzenes with the method provided by this invention, total hydroxybenzene extraction ratio can be as high as 92%. Besides, it also has the advantages of simple technique, soft conditions and recyclable extraction solution.

Description

technical field [0001] The invention relates to a method for treating and recovering wastewater, in particular to a method for extracting and removing phenols from gasification wastewater containing high-concentration phenol-containing coal. Background technique [0002] Phenols are protoplasmic poisons and have toxic effects on all living individuals. Very low content can still cause chronic poisoning, and when the concentration is higher than 1mg / L, it can directly lead to the death of organisms, seriously endangering ecology and the environment. Coal gasification, oil refining and coking industries produce a large amount of phenol-containing wastewater in the production process. The quality of the wastewater is very complicated, the concentration of phenol is high, and there are many types of phenols, including both unit phenols and polyphenols; the water quality is moderately alkaline; Contains organic substances such as fatty acids, ketones and amines, acid gases, tar,...

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): C02F9/14C02F1/26
Inventor 章莉娟钱宇杨楚芬冯建中
Owner SOUTH CHINA UNIV OF TECH
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