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

Method for extracting aluminum oxide from fluidized bed coal ash

A technology of fly ash and fluidized bed, applied in the field of resource circulation, can solve problems such as equipment corrosion, environmental pollution, and difficulty in large-scale industrialization, and achieve the effect of reducing flow and facilitating industrialization.

Inactive Publication Date: 2014-04-09
CHANGAN UNIV
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] Fluidized bed fly ash, due to the low coal combustion temperature and high activity of fly ash (slag), the alumina extraction process has certain advantages over pulverized coal furnace fly ash, but the existing acid method for extracting fluidized bed powder The technology of alumina in coal ash is difficult to industrialize on a large scale due to the risk of equipment corrosion and environmental pollution

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

[0028] Step 1, mixing 100g of fluidized bed fly ash with 500g of a 10% sodium hydroxide aqueous solution, and then placing the mixture in a ball mill for wet ball milling to obtain a slurry with a particle size not greater than 100 mesh;

[0029] Step 2. Pre-desiliconize the slurry described in step 1 under normal pressure at a temperature of 95° C. for 2 hours, and filter the reaction product after the reaction to obtain a filter cake;

[0030] Step 3: Add 60g of calcium oxide, 160g of sodium hydroxide, and 800g of water to the filter cake described in step 2, and then use high-pressure hydrochemical method at a temperature of 300°C and a pressure of 8MPa for hydrothermal reaction for 2h, after cooling The reaction product is vacuum filtered to obtain filter residue and filtrate; CaO and SiO in the hydrothermal reaction system 2 The molar ratio is 2:1, Na 2 O and Al 2 o 3 The molar ratio is 7:1, Na in the hydrothermal reaction system 2 The concentration of O reaches 150g / ...

Embodiment 2

[0037] Step 1, mixing 100g of fluidized bed fly ash with 250g of a 20% sodium hydroxide aqueous solution, and then placing the mixture in a ball mill for wet ball milling to obtain a slurry with a particle size not greater than 100 mesh;

[0038] Step 2. Pre-desiliconize the slurry described in step 1 at 95°C under normal pressure for 1.5 hours, and filter the reaction product after the reaction to obtain a filter cake;

[0039] Step 3: Add 55g of calcium oxide, 150g of sodium hydroxide, and 850g of water to the filter cake described in step 2, then use high-pressure hydrochemical method at a temperature of 320°C and a pressure of 12MPa for hydrothermal reaction for 1h, after cooling The reaction product is vacuum filtered to obtain filter residue and filtrate; CaO and SiO in the hydrothermal reaction system 2 The molar ratio is 2:1, Na 2 O and Al 2 o 3The molar ratio is 5:1, Na in the hydrothermal reaction system 2 The concentration of O reaches 120g / L; the filter residue...

Embodiment 3

[0046] Step 1, mixing 100g of fluidized bed fly ash with 200g of a 25% sodium hydroxide aqueous solution, and then placing the mixture in a ball mill for wet ball milling to obtain a slurry with a particle size not greater than 100 mesh;

[0047] Step 2. Pre-desiliconize the slurry described in step 1 at 95°C under normal pressure for 1 hour, and filter the reaction product after the reaction to obtain a filter cake;

[0048] Step 3: Add 55g of calcium oxide, 150g of sodium hydroxide, and 830g of water to the filter cake described in step 2, then use high-pressure hydrochemical method at a temperature of 310°C, and a pressure of 10MPa for hydrothermal reaction for 1h, after cooling The reaction product is vacuum filtered to obtain filter residue and filtrate; CaO and SiO in the hydrothermal reaction system 2 The molar ratio is 2:1, Na 2 O and Al 2 o 3 The molar ratio is 6:1, Na in the hydrothermal reaction system 2 The concentration of O reaches 140g / L; the filter residue ...

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
particle sizeaaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for extracting aluminum oxide from fluidized bed coal ash, comprising the following steps: 1, mixing the fluidized bed coal ash and sodium hydroxide aqueous solution and carrying out ball milling to obtain slurry; 2, carrying out pre-desilicication reaction on the slurry, and filtering; 3, adding calcium oxide, sodium hydroxide and water in a filter cake, carrying out hydrothermal reaction by utilizing a high-pressure water chemical method, vacuum filtering; 4, adding hydration sodium aluminosilicate in the filtrate to carry out the first-stage desilicication reaction, and adding hydration calcium aluminate to carry out the second-stage desilicication reaction; 5, evaporating and crystallizing the reaction liquid to obtain hydration sodium aluminate, and crystallizing; 6, dissolving and crystallizing, introducing carbon dioxide and filtering to obtain aluminum hydroxide solid; and 7, washing and calcining to obtain aluminum oxide. By utilizing high activity of the fluidized bed coal ash, the amount of the subsequent aluminum oxide extract is greatly reduced through pre-desilicication reaction so as to ensure industrialization; and the silicon oxide and aluminum oxide in the coal ash are separated by adding alkaline substances and utilizing the high-pressure water chemical method so as to save energy and protect the environment.

Description

technical field [0001] The invention belongs to the technical field of resource recycling, and in particular relates to a method for extracting alumina from fluidized bed fly ash. Background technique [0002] Fly ash is a solid by-product obtained from the combustion of coal-fired boilers in thermal power plants. With the development of society and the advancement of science and technology, fly ash has long been a hot resource in many areas of our country, and the supply is in short supply. With the extraordinary and rapid development of thermal power plants in our country, the utilization situation of fly ash discharged from energy-rich areas is still severe. . In particular, tens of millions of tons of high-aluminum fly ash are produced every year in northern my country. This rare resource in the world has become a hot spot in coal, electric power, non-ferrous metals, building materials and other related industries. The extraction of alumina from fly ash is also a It has...

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): C01F7/02B09B3/00
Inventor 赵鹏
Owner CHANGAN 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