Method for separating lignin and hemicellulose from papermaking black liquor and recovering lye

A technology for hemicellulose and papermaking black liquor, which is applied in the fields of environmental protection and resource recycling, can solve the problems of not mentioning alkali lignin acidification and recovery, not mentioning alkali liquor recovery and hemicellulose separation and recovery, etc. vegan and hemicellulose purifying, contaminant-removing effects

Active Publication Date: 2017-10-31
GUANGXI ACAD OF SCI
View PDF12 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In Patent 3, the black liquor is first adjusted to pH=8-10. At this time, a considerable amount of alkali lignin has been transformed into lignin suspension and separated. Pretreatment with mechanical vibrating screen filter or bag filter will cause lignin Loss of loss, followed by 2 or more membrane separation, intercepted should be alkali lignin, no mention of acidification recovery of alkali lignin, no mention of alkali recovery and hemicellulose separation and recovery

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 separating lignin and hemicellulose from papermaking black liquor and recovering lye
  • Method for separating lignin and hemicellulose from papermaking black liquor and recovering lye
  • Method for separating lignin and hemicellulose from papermaking black liquor and recovering lye

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0041] In this example, 20 liters of poplar alkali papermaking black liquor was taken, and the steps listed in the content of the present invention were used to separate hemicellulose and lignin, and to recover the lye. The specific preparation process is as follows:

[0042] The method for separating lignin and hemicellulose from papermaking black liquor and reclaiming lye, the preparation process comprises the following steps:

[0043] (1) Put 20 liters of poplar papermaking black liquor in a separation container, remove insoluble suspended matter with a screen, settle for 4 hours after stirring, and then discharge the lower layer of sediment;

[0044] (2) First-stage ultrafiltration of papermaking black liquor to intercept and recover hemicellulose;

[0045] (3) Second-stage ultrafiltration of papermaking black liquor to intercept alkali lignin and recover alkali liquor;

[0046] (4) Acidify the alkali lignin to precipitate lignin; put the retained alkali lignin into the ...

Embodiment 2

[0058] In this example, 20 liters of wheatgrass alkaline papermaking black liquor was taken, and the steps listed in the content of the present invention were used to separate hemicellulose and lignin, and recover the lye. The specific preparation process is as follows:

[0059] (1) Put 20 liters of wheat straw papermaking black liquor in a separation container, remove insoluble suspended matter with a screen, settle for 4 hours after stirring, and then discharge the lower layer of sediment;

[0060] (2) First-stage ultrafiltration of papermaking black liquor to intercept and recover hemicellulose;

[0061] (3) Second-stage ultrafiltration of papermaking black liquor to intercept alkali lignin and recover alkali liquor;

[0062] (4) Acidify the alkali lignin to precipitate lignin; put the retained alkali lignin into the acidifier, add sulfuric acid with a mass concentration of 5-10% for acidification, and keep stirring to adjust to pH=2.5-3. Suspended flocculent lignin appea...

Embodiment 3

[0074] In this example, 20 liters of eucalyptus alkaline papermaking black liquor was taken, and the steps listed in the content of the present invention were used to separate hemicellulose and lignin, and recover the lye. The specific implementation process is as follows:

[0075](1) Put 20 liters of eucalyptus papermaking black liquor in a separation container, remove insoluble suspended matter with a screen, settle for 4 hours after stirring, and then discharge the lower layer of sediment;

[0076] (2) First-stage ultrafiltration of papermaking black liquor to intercept and recover hemicellulose;

[0077] (3) Second-stage ultrafiltration of papermaking black liquor to intercept alkali lignin and recover alkali liquor;

[0078] (4) Acidify the alkali lignin to precipitate lignin; put the retained alkali lignin into the acidifier, add sulfuric acid with a mass concentration of 5-10% for acidification, and keep stirring to adjust to pH=2.5-3. Suspended flocculent lignin appe...

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
thermal resistanceaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for separating lignin and hemicellulose from papermaking black liquor and recycling alkali liquor.The method comprises the steps that hemicellulose is intercepted from first grade of ultrafiltration (15-25 KD ceramic filtration membrane), alkali lignin is intercepted from second grade of ultrafiltration (1-15 KD ceramic filtration membrane), dialytic alkali liquor is recycled and acidized by dilute sulphuric acid to obtain lignin suspension liquid, and purified lignin is obtained through operation such as stirring settlement, sediment eliminating, centrifugal filtration (or pressure filtration), acid pickling and deionized water washing.According to the method, major pollutants in the papermaking black liquor are eliminated, high value-added lignin and hemicellulose are separated, the alkali liquor is recycled, the used acid content is small, zero emission or extra little emission is realized, the operation cost is low, and the method has high social benefits and economic benefits.

Description

technical field [0001] The invention relates to the fields of environmental protection and resource recycling, in particular to a method for separating lignin and hemicellulose from papermaking black liquor and recovering lye. Background technique [0002] my country's paper industry mainly uses various wood and herbaceous plants as raw materials, such as poplar, pine, fir, eucalyptus, reed, wheat straw, straw, corn stalks, corncobs, bagasse, etc. The paper industry discharges a large amount of smelly and toxic black liquor, the main components of which are hemicellulose and lignin that cannot be metabolized by microorganisms. It is estimated that the annual discharge of lignin by my country's paper industry is as high as 40 million tons. At present, the main way to deal with papermaking black liquor is to mix it with coal powder from power plants and burn it after concentration. At present, more than 95% of lignin and hemicellulose are discharged with untreated papermaking...

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 Patents(China)
IPC IPC(8): D21C11/04C08H7/00C08B37/14
CPCC07G1/00C08B37/14D21C11/04
Inventor 杜奇石黎演明唐培朵黄华林杜芳黎黄慨龙思宇黄日波
Owner GUANGXI ACAD OF SCI
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