Process for extracting aluminium hydroxide from flyash

A technology of fly ash and alumina, applied in the preparation of alumina/hydroxide, alkali metal aluminate/alumina/aluminum hydroxide, etc., can solve the problems that hinder the fine development and utilization of fly ash and resource utilization problems such as low rate and low dissolution rate, to achieve the effect of high product added value, small investment and simple process

Inactive Publication Date: 2006-06-28
朔州市人民政府 +2
View PDF0 Cites 87 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Recovery of Al from fly ash by the above method 2 o 3 , Al 2 o 3 The dissolution rate of the fly ash is relatively low, generally only 35-45%, the resource utilization rate is l

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

[0024] Take 1 ton of fly ash containing 40% alumina, grind it into 300-mesh fine powder, remove iron by magnetic separation, and roast at 400°C for 1.5h to obtain activated fly ash.

[0025] Adding 72% H to activated fly ash 2 SO 4 4t, heat up to 300°C for leaching reaction for 1h, so that the alumina can be fully leached, the reacted material is separated from solid and liquid at 150°C, and the filtered residual acid is recovered and used in the next leaching process for recycling.

[0026] Add 4 t of water to the solid residue, heat up to 80°C and boil for 40 minutes, filter, wash the filter residue with water twice, and use the lotion in reverse.

[0027] The filtrate was evaporated and concentrated, and the evaporated water vapor was condensed and then returned to the stripping process. After the concentrated solution was cooled, aluminum sulfate crystals were precipitated, filtered, and 2200Kg of solid crystals were collected. The filtrate is evaporated and concentrate...

Embodiment 2

[0033] Take 1 ton of fly ash containing 40% alumina, grind it into 200-mesh fine powder, remove iron by magnetic separation, and roast at 600°C for 1 hour to obtain activated fly ash.

[0034] Add 98% H to activated fly ash 2 SO 4 2t, heat up to 250°C for 1.5h of leaching reaction, so that alumina can be fully leached, after the reaction, the material is separated from solid and liquid at 180°C, and the filtered residual acid is recovered and used in the next leaching process for recycling.

[0035] Add 6 t of water to the solid residue, raise the temperature to 75°C and boil for 45 minutes, filter, wash the filter residue twice with water, and use the lotion in reverse.

[0036] The filtrate was evaporated and concentrated, and the evaporated water vapor was condensed and then returned to the stripping process. After the concentrated solution was cooled, aluminum sulfate crystals were precipitated, filtered, and 2200Kg of solid crystals were collected. The filtrate is evap...

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

A process for extracting aluminum oxide from powdered coal ash includes such steps as grinding, calcining, mixing with H2SO4 solution, heating while reaction for extracting aluminum oxide, boiling in water, concentrating, cooling while educing out aluminum sulfate crystals, heating for dewatering, heating for decomposing to obtain gamma-Al2O3, and further preparing metallurgy-class aluminum oxide.

Description

Technical field [0001] The invention belongs to the refined comprehensive utilization of fly ash, in particular to a method for extracting alumina from fly ash. Background technique [0002] A large amount of fly ash emitted by coal-fired power plants has caused serious pollution to the surrounding agricultural production and living environment. Comprehensive treatment of fly ash has become an urgent environmental problem that needs to be solved. In my country, the amount of fly ash discharged by coal-fired power plants is as high as hundreds of millions of tons every year, and the stockpile is very large. Al in fly ash 2 o 3 The content is relatively high, about 20-40%. Due to the large stockpile, it is a treasure house of resources with great value for refined and comprehensive development and utilization. [0003] Extraction of Al from fly ash at home and abroad 2 o 3 The methods can be divided into two categories: alkali method and acid method. In the 1960s, Poland...

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): C01F7/32C01F7/14
Inventor 秦晋国翟玉春
Owner 朔州市人民政府
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