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

A red mud citric acid dealkalization process

A technology of citric acid and red mud, applied in the field of comprehensive treatment of red mud, can solve the problems of large consumption of chemicals, high liquid-solid ratio, red mud cannot be used as preparation, etc., and achieve the effect of reducing consumption of chemicals

Active Publication Date: 2017-05-10
HENAN POLYTECHNIC UNIV
View PDF14 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, the red mud dealkalization process mainly includes the following methods: water immersion process (Zhang Guoli, Li Shaochun, Zhang Xinyuan, etc. "Study on the Bayer process of red mud water washing and alkali removal process", Journal of Qingdao University of Technology, 2012, 33(4): 59 -62) There are low dealkalization rate, high alkalinity of dealkalization solution, high liquid-solid ratio, high washing times, red mud after dealkalization cannot be used as raw materials for the preparation of building materials and environmental adsorption materials
Carbon dioxide leaching process (Wang Zhi, Han Minfang, Zhang Yihe, etc. "Study on Wet Carbonization Dealkalization Process of Bayer Process Red Mud" Silicate Bulletin, 2013, 32 (9): 1851-1855) has low dealkalization rate and leaching Defects such as high equipment performance requirements and low activity of red mud after treatment
Hydrochloric acid leaching process (Zhong Chen, Xia Jupei, "Na in Bayer process red mud + Leaching Experimental Research of "Silicate Bulletin, 2013, 32(9): 2012-2015) there is a large amount of acid consumption in the dealkalization process, high acidity of the dealkalization solution and strong acidity of the red mud after treatment, resulting in secondary pollution, etc. defect
Lime leaching process (Li Shaokang, Liang Chunlai, Li Guangzhu, etc. "A Bayer red mud atmospheric pressure dealkalization method", invention patent, 2004) has defects such as low dealkalization rate, large chemical consumption and high energy consumption

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
  • A red mud citric acid dealkalization process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0026] The first batch of red mud undergoes a stirring leaching and a water washing:

[0027] The first batch of red mud and citric acid with an added amount of 12% to 15% of the red mud mass percentage are stirred and leached under the condition of a liquid-solid mass ratio of 3 to 5:1. The leaching process is at a temperature of 30 to 40°C, The stirring time is 90~120min and the stirring intensity is 100~150r / min. After stirring, the slurry is filtered under pressure to obtain acidic leaching residue and acidic leaching liquid. The acidic leaching liquid is the first-level dealkalizing liquid of the first batch of red mud. After washing, the first batch of red mud desalination residue and washing liquid are obtained, and then the second batch of red mud desalination liquid is obtained after adding 7% to 8% of the mass percentage of the washing liquid to the washing liquid.

[0028] The second batch of red mud is subjected to a second stirring and leaching and a water washing:

[0...

Embodiment 2

[0036] The first batch of red mud undergoes a stirring leaching and a water washing:

[0037] The first batch of red mud and citric acid with an added amount of 9% to 12% of the red mud mass percentage are leached under the conditions of a liquid-solid mass ratio of 3 to 5:1. The leaching process is at a temperature of 40-50 ℃, The stirring time is 90~120min and the stirring intensity is 100~150r / min. After stirring, the slurry is filtered under pressure to obtain acidic leaching residue and acidic leaching liquid. The acidic leaching liquid is the first-level dealkalizing liquid of the first batch of red mud. After washing, the first batch of red mud desalination residue and washing liquid are obtained, and then the second batch of red mud desalination liquid is obtained after adding 6% to 7% of the mass percentage of the washing liquid to the washing liquid.

[0038] The second batch of red mud is subjected to a second stirring and leaching and a water washing:

[0039] Mix the se...

Embodiment 3

[0046] The first batch of red mud undergoes a stirring leaching and a water washing:

[0047] The first batch of red mud and citric acid with an added amount of 6%-9% of the red mud mass percentage are leached under the conditions of a liquid-solid mass ratio of 3~5:1. The leaching process is at a temperature of 50~60℃, The stirring time is 90~120min and the stirring intensity is 100~150r / min. After stirring, the slurry is filtered under pressure to obtain acidic leaching residue and acidic leaching liquid. The acidic leaching liquid is the first-level dealkalizing liquid of the first batch of red mud. After washing, the first batch of red mud desalination residue and washing liquid are obtained, and then the second batch of red mud desalination liquid is added after adding 5% to 6% of the mass percentage of the washing liquid to the washing liquid.

[0048] The second batch of red mud is subjected to a second stirring and leaching and a water washing:

[0049] Mix the second batch ...

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 red-mud citric acid dealkalizing technique. According to the technique, citric-acid three-level cross-flow dealkalizing operation is carried out on red mud, and Bayer-process red mud is dealkalized through citric acid. Due to the fact that the citric acid is organic tribasic acid, sodium and potassium in the red mud can be effectively removed under the condition of the lower citric acid using amount and the low temperature, the pH value of the dealkalized sludge ranges from 6.5 to 7.5, and the dealkalized sludge can be dammed and piled. Residual citric acid in the dealkalized sludge of the red mud can be degraded biologically, has a repairing function on alkaline soil and can serve as a modifying agent for the alkaline soil. The citric acid can generate calcium citrate sediment with other elements like calcium, so that calcium can be solidly stored in the dealkalized sludge of the red mud to be used as raw materials for manufacturing building materials. Elements like titanium, scandium and rare earth are difficult to dissolve out, the taste of the elements in the dealkalized sludge of the red mud is improved, and the dealkalized sludge can be used as raw materials to extract valuable rare metal. According to the red-mud citric acid dealkalizing technique, the citric acid can be recycled, and the consumption of chemical agents is reduced. In addition, the pH value of obtained dealkalized liquid ranges from 6.5 to 7.5, the dealkalized liquid does not contain heavy metal ions, and the dealkalized liquid can be drained and utilized.

Description

Technical field [0001] The invention relates to the technical field of red mud comprehensive treatment, in particular to a red mud citric acid dealkalization process. Background technique [0002] Bayer process red mud is the tailings produced in the aluminum smelting process of Bayer process. It is a kind of strong alkaline solid pollutant. Its storage process will cause groundwater and soil pollution. In addition, the high alkali content in red mud is a key factor restricting the extraction of valuable rare and precious metals from red mud, the preparation of construction materials and environmental adsorption materials, so effective measures must be taken to treat this type of solid waste. At present, the red mud desalination process mainly includes the following methods: water leaching process (Zhang Guoli, Li Shaochun, Zhang Xinyuan, etc.·"Bayer Process Red Mud Water Elution Process"·Journal of Qingdao Technological University, 2012, 33(4): 59 -62) The dealkalizing rate is ...

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): B03B7/00
CPCB03B7/00
Inventor 朱晓波李望管学茂张乾陆银平张玉德
Owner HENAN POLYTECHNIC UNIV
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