Method for removing sodium oxalate from industrial sodium aluminate solution

A technology for industrial sodium aluminate and sodium oxalate, applied in the field of impurity sodium oxalate, can solve the problems of calcium oxalate crystal seed being easy to lose activity, unfavorable sodium oxalate crystallization precipitation, sodium oxalate easy to lose activity, etc., achieving low cost, pretreatment Simple process, easy to separate effects

Inactive Publication Date: 2008-11-12
GUIZHOU BRANCH CHINA ALUMINUM IND
View PDF11 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

When solid sodium oxalate is added as a seed crystal, the sodium oxalate will easily lose its activity during the circulation process, which will affect the crystallization process and is not conducive to the crystallization of sodium oxalate. At the same time, the sodium oxalate crystal s

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 removing sodium oxalate from industrial sodium aluminate solution

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0045] Example 1

[0046] The concentration of caustic alkali in the decomposition mother liquor of an alumina factory is 162g / L. When the concentration of caustic alkali is 243g / L after evaporation and concentration, at a constant temperature of 40℃, 20g / L aluminum hydroxide seed crystals are added, and the rotation speed is 100r / Stir for 12 hours under the condition of min, stop stirring, filter the slurry with a vacuum filter, and return the filtrate to the main production process of Bayer Process. The filter cake is washed with hot water at 60℃ and filtered with a vacuum filter. The composition of the filter cake is hydroxide. Aluminum is used as the seed crystal for the next batch of sodium aluminate solution to crystallize sodium oxalate. The filtrate mainly contains sodium oxalate, and caustic is recovered by causticization. After the above treatment, the sodium oxalate content in the sodium aluminate solution returned to the main production process of the Bayer process de...

Example Embodiment

[0047] Example 2

[0048] The concentration of caustic alkali in the decomposition mother liquor of an alumina factory is 162g / L, and when the concentration of caustic alkali is 180g / L after evaporation and concentration, at a constant temperature of 20°C, 10g / L aluminum hydroxide seed crystals are added, and the speed is 100r / Stir for 24 hours under the condition of min, stop stirring, filter the slurry with a vacuum filter, and return the filtrate to the main production process of Bayer Process. The filter cake is washed with hot water at 60℃ and filtered with a vacuum filter. The composition of the filter cake is hydroxide. Aluminum is used as the seed crystal for the next batch of sodium aluminate solution to crystallize sodium oxalate. The filtrate mainly contains sodium oxalate, and caustic is recovered by causticization. After the above treatment, the sodium oxalate content in the sodium aluminate solution returned to the main production process of the Bayer process decrea...

Example Embodiment

[0049] Example 3

[0050] The concentration of caustic alkali in the decomposition mother liquor of an alumina factory is 162g / L, and when the concentration of caustic alkali is 243g / L after evaporation and concentration, at a constant temperature of 35℃, 20g / L aluminum hydroxide seed crystals are added, and the speed is 100r / Stir for 48 hours under the condition of min, stop stirring, filter the slurry with a vacuum filter, and return the filtrate to the main production process of Bayer Process. The filter cake is washed with hot water at 60℃ and filtered with a vacuum filter. The composition of the filter cake is hydroxide. Aluminum is used as the seed crystal for the next batch of sodium aluminate solution to crystallize sodium oxalate. The filtrate mainly contains sodium oxalate, and caustic is recovered by causticization. After the above treatment, the sodium oxalate content in the sodium aluminate solution returned to the main production process of the Bayer process decreas...

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 method discloses a method for removing sodium oxalate in an industrial sodium aluminate solution, which is in particular suitable for removing impurity sodium oxalate in the sodium aluminate solution in the process of producing alumina in a Bayer process. The method comprises the following steps that: a decomposition mother solution is evaporated, condensed and cooled; aluminium hydroxide is added as an inoculating seed in order that a sodium oxalate crystallinesubstance in the decomposition mother solution is separated out and filtered; and the crystallinesubstance is separated, thereby removing the sodium oxalate in the sodium aluminate solution. Through the treatment by the method, the sodium oxalate concentration in the sodium aluminate solution is reduced; the method reduces the influence of the sodium oxalate on the production process, makes for the smoothness of the production in the Bayer process and has marked effect, simple process and good industrial application prospect.

Description

technical field [0001] The invention relates to a method for removing sodium oxalate in industrial sodium aluminate solution, and is particularly suitable for removing impurity sodium oxalate in sodium aluminate solution in the process of producing alumina by Bayer process. Background technique [0002] Bauxite often contains a few parts per thousand to a few parts per thousand of organic carbon. These organic matter can be divided into humic acid and asphalt two categories. The latter is practically insoluble in alkaline solution and is all discharged along with the red mud. The organic matter of humic acid reacts with alkali to generate various sodium humates, and then gradually transforms into sodium oxalate (Na 2 C 2 o 4 ) and other low molecular weight organic compounds and sodium carbonate. The content of sodium oxalate in the sodium aluminate solution of different alumina plants depends on the type of raw material to be processed, the characteristics of the disso...

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): C01F7/04
Inventor 陈文汩胡玉波吴海文谭秋奇龙旭邹勇明郭金权
Owner GUIZHOU BRANCH CHINA ALUMINUM 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

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