Iron removal method of high-iron gibbsite bauxite

Abstract

The invention discloses an iron removal method of high-iron gibbsite bauxite, which comprises the following steps of crushing and grinding high-iron gibbsite bauxite raw ore to obtain ground ore, wherein the mass percentage content of oversize ore particles obtained after the levigated ore passes through a sieve with the pore diameter of 150 microns is 5%-20%, and the mass percentage content of undersize ore particles obtained after the levigated ore passes through a sieve with the pore diameter of 250 microns is 99%-100%, preparing ore slurry from the levigated ore and water, and carrying outhydrothermal reaction to obtain mixed slurry, carrying out magnetic separation on the mixed slurry to obtain strong magnetic component solids with high iron oxide content and gibbsite bauxite slurrywith low iron oxide content, and carrying out solid-liquid separation on the gibbsite bauxite slurry with low iron oxide content, and enabling the obtained solid to enter an aluminum oxide productionprocess. According to the method, iron-containing minerals are separated out before bauxite enters the aluminum oxide production process, so that environmental protection is facilitated, and the aluminum oxide production cost is reduced.

Description

technical field [0001] The invention belongs to the field of alumina metallurgy, in particular to a method for removing iron from high-iron gibbsite type bauxite. Background technique [0002] Worldwide, gibbsite-type bauxite is the main raw material for alumina production. Usually, the impurity minerals with the highest content in gibbsite ore are iron-containing minerals. After the alumina is extracted from gibbsite ore, the iron-containing minerals enter the red mud and become a kind of industrial waste. Due to the influence of the alkali content in the red mud, the iron in it is difficult to recycle and has to be discharged together with the red mud. Bringing environmental pollution and waste of resources. Therefore, along with the development of alumina industry, the selection of iron from bauxite and iron from red mud has always been a research hotspot. [0003] The main difficulty in iron selection in bauxite is how to break the inclusion and intercalation relations...

AI Technical Summary

Problems solved by technology

After the alumina is extracted from gibbsite ore, the iron-containing minerals enter the red mud and become a kind of industrial waste. Due to the influence of the alkali content in the red mud, the iron in it is difficult to recycle and has to be discharged together with the red mud. Environmental pollution and waste of resources

Chinese patent CN102583477B introduces a technical route of first extracting alumina from bauxite, and then smelting the dissolved red mud to extract iron. This technology still has the problems of high energy consumption and separation of iron and alkali in the ignition method.

Chinese patent CN102515223B uses hydrochloric acid to react with high-iron bauxite in a pressurized reactor to obtain aluminum chloride and ferric chloride solution and high-silicon slag; adding excess sodium hydroxide lye can obtain sodium aluminate solution and high-iron slag, Chlorine gas, hydrogen gas, sodium hydroxide solution and pure sodium aluminate solution are obtained by electrolysis; sodium aluminate solution can be used to produce metallurgical grade alumina. This technology has problems such as long process, high equipment specification requirements, and high environmental pressure.

Chinese patent CN101417260B has introduced a kind of bauxite flotation technology, after grinding bauxite finely, iron and aluminum minerals are separated by combined magnetic separation and flotation; "Experimental Research" and "Study on Raw Ore Slurry Iron Separation Technology of Pingguo Bauxite" also introduced the related technologies of magnetic separation and flotation to treat high-iron bauxite; in this kind of technology, it is difficult to remove iron, Embedded distribution and inclusion of aluminum minerals, general beneficiation effect, high magnetic component iron oxide content is not high

The biggest problem in the technology of selecting iron from red mud is that it is difficult to completely separate iron and alkali, which affects the effective utilization of the selected high-iron components

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