Method for recycling iron from waste red mud in alumina production

A technology for recovering iron and alumina, which is applied to the improvement of process efficiency, details of furnaces and blast furnaces, etc., can solve the problems of low thermal efficiency of electric furnace ironmaking, unfavorable comprehensive utilization of tailings, and low grade of iron concentrate, achieving significant economic and Social benefit, production realization, good pig iron quality effect

Inactive Publication Date: 2013-05-01
GUIZHOU BRANCH CHINA ALUMINUM IND
View PDF4 Cites 31 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, because iron is wrapped or mixed with other minerals in red mud, there are problems such as low iron concentrate grade (~63%) and low iron recovery rate (~90%), which is not conducive to the comprehensive utilization of tailings. Producer gas or blast furnace gas and kiln

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 recycling iron from waste red mud in alumina production

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] The solid waste red mud produced by alumina is dried, and the dried red mud is crushed, the particle size is ≤0.15mm, the water content is 1-2%, and the red mud pellets of ? Exhaust gas is used to dry the red mud balls until the water content is less than or equal to 1%. The dry red mud balls are mixed with coke, limestone and dolomite according to the following ratio: red mud 60kg, coke 30kg, limestone 5kg, dolomite 3kg, directly add into the blast furnace, and at the same time, the blower blows air into the blast furnace. The air passes through the hot blast stove and heats the air to 450°C, so that the smelting temperature in the blast furnace reaches 1500-1650°C, and the temperature of slag and iron is 1400-1450°C. The obtained product Pig iron and slag will be comprehensively utilized in the future.

[0025] After testing, the obtained metallic iron is of good quality, including Fe: 94.164%, C: 3.86%, Si: 0.36%, Mn: 0.11%, P: 0.025%, S: 0.054%.

[0026] The analys...

Embodiment 2

[0027] Example 2, the solid waste red mud produced by alumina is dried, the water content is 9-10%, the dried red mud is crushed, the particle size is ≤0.15mm, and the red mud pellets of ?30 are obtained through 50kN pressure. The tail gas of the blast furnace ironmaking is dried to the red mud balls until the water content is ≤1%, and the dry red mud balls are mixed with coke, limestone and dolomite according to the following ratio: 80kg red mud, 20kg coke, 10kg dolomite, directly Add it into the blast furnace, and at the same time blow air into the blast furnace from the blower. The air passes through the hot blast stove and heats the air to 1100°C, so that the smelting temperature in the blast furnace reaches 1500-1650°C, and the temperature of slag and iron is 1400-1480°C. carry out subsequent comprehensive utilization.

[0028] After testing, the obtained metallic iron is of good quality, including Fe: 94.164%, C: 3.82%, Si: 0.41%, Mn: 0.41%, P: 0.087%, S: 0.052%.

[002...

Embodiment 3

[0030] Example 3, the solid waste red mud produced by alumina is dried, the water content is 5-6%, the dried red mud is crushed, the particle size is ≤0.15mm, and red mud pellets of ?15 are obtained through 70kN pressure. The tail gas of the blast furnace ironmaking is dried to the red mud balls until the water content is ≤1%, and the dry red mud balls are mixed with coke, limestone and dolomite iron ore according to the following ratio: red mud 30kg, coke 25kg, iron ore 40kg of limestone and 10kg of limestone are directly added to the blast furnace, and at the same time, the blower blows air into the blast furnace. 1400~1450℃, the slag will be used for subsequent comprehensive utilization.

[0031] After testing, the obtained metallic iron is of good quality, including Fe: 94.98%, C: 3.82%, Si: 0.25%, Mn: 0.65%, P: 0.065%, S: 0.032%.

[0032] The analysis result of the slag is: Fe 2 o 3 : 0.83%, TiO 2 : 4.32%, CaO: 20.67%, SiO 2 : 19.42%, Al 2 o 3 : 28.25%, Na 2 O: 3....

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
Granularityaaaaaaaaaa
Login to view more

Abstract

The invention relates to a method for recycling iron from waste red mud in alumina production. The method is characterized in that waste red mud in alumina production is dried, the moisture content after drying ranges from 1% to 10%, the particle size of the smashed red mud is less than or equal to 0.15mm, and the red mud is manufactured into pellets of 15mm to 50mm under the pressure ranging from 10kN to 70kN. Heat produced by blast furnace gas burning is used to dry the red mud pellets to be with a moisture content less than or equal to 1%, then the dried red mud pallets, coke, limestone and dolomite are mixed according to the proportion and added into a blast furnace to be smelted directly, finally the mixture is separated through iron slag to obtain metallic iron and slag, iron can directly serve as a steel-making material, and the slag can be recycled for subsequent comprehensive utilization. According to the method, industrial waste serves as a main material, environmental pollution is reduced, and the waste can be recycled; and the method has the advantages that the quality of the recycled iron is good, the iron recovery rate is high and can achieve more than 98%, the technological process is simple, the production is easily achieved, and tailings after iron removal are easily processed.

Description

technical field [0001] The invention belongs to the technical field of alumina production red mud treatment technology, and in particular relates to a process method for directly recovering valuable metal iron from red mud, which is solid waste produced by diaspore Bayer process alumina. Background technique [0002] In the production of diaspore Bayer process alumina, bauxite is mixed with lime and circulating lye to make qualified pulp and then dissolved. Under the action of high temperature and high pressure, the alumina in the ore enters the solution, and its insoluble matter is red mud. After the dissolution, the ore pulp is diluted and settled for solid-liquid separation, and the bottom flow red mud slurry produced is reverse washed three times, filtered to recover the attached alkali, and then discharged. The production of 1 ton of alumina will produce 1.1 to 1.5 tons of red mud. With the rapid development of the alumina industry in recent years, the global annual al...

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): C21B5/00
CPCY02P10/20
Inventor 刘保伟甘霖许家伟张正林冷杰彬谭金玉
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