Method of refining iron ore from alkaline red mud and making gangue neutral

Abstract

The invention relates to a method to select refined iron ore from alkaline red mud and neutralize mine tailings. The method consists of red mud pretreatment and technological process of preparing refined iron ore. The red mud pretreatment is that water is added into the red mud slurry discharged from aluminum factory; the red mud slurry is diluted to the solid concentration of 30 to 40 percent and then is screened and put into a low intensity magnetic separator for selecting ferromagnetic substance. The ferromagnetic substance is dehydrated and directly selected as the product. The remaining red mud is watered down to 30 percent solid concentration and put into a high intensity magnetic separator for magnetic separation and desliming. The obtained coarse ore is washed to a coarse ore settling tank or a thickener to be concentrated while the undercurrent is sent into a vacuum ceramic filter and a filter cake is roasted in a suspended magnetic roasting furnace. The roasted materials are crushed into a ball mill and then are milled. The water is overflown until 95 percent of the solid material granularities are less than 75m and then is treated by the third stage magnetic separation and the second flotation. The undercurrent is filtered by the ceramic filter, and then the refined iron ore with a purity of 58 to 65 percent is obtained. The refined iron ore is recycled from the red mud by the invention so as to fully employ aluminum ore, save resources and energy consumption and neutralize the whole red mud. The invention reduces environmental pollution and has good economic and social benefits.

Description

technical field [0001] The invention relates to a method for extracting iron-containing substances from waste ore pulp, in particular to a method for extracting iron-containing substances, that is, iron concentrate, from waste red mud pulp produced in the process of producing alumina. Background technique [0002] During the alumina production process, the alumina in the ore is dissolved in alkali and enters the sodium aluminate solution, and other minerals, including iron oxide, are precipitated in a solid state. These solid substances are red because they contain iron oxide, so they are called red mud. Red mud is strongly alkaline and is a pollutant that has a serious impact on the environment. During the storage process, a storage yard with complete anti-seepage measures must be built. The capital construction and maintenance costs are high, and a large amount of land is occupied. By adopting the method for recovering iron ore from red mud of the present invention, fine i...

AI Technical Summary

Problems solved by technology

Red mud is strongly alkaline and is a pollutant that has a serious impact on the environment. During the storage process, a storage yard with complete anti-seepage measures must be built. The capital construction and maintenance costs are high, and it takes up a lot of land.

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