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CN-122012914-A - Method for recycling high-iron high-silicon bauxite

CN122012914ACN 122012914 ACN122012914 ACN 122012914ACN-122012914-A

Abstract

The invention provides a method for recycling high-iron high-silicon bauxite, which comprises the steps of (1) grinding the high-iron high-silicon bauxite, roasting in an oxidizing atmosphere at 1000-1200 ℃, cooling an oxidized roasting material to 600-800 ℃ for reduction roasting, (3) carrying out alkaline leaching on a reduction roasting product to obtain alkaline leaching slag and leaching liquid, (4) leaching the alkaline leaching slag by adopting a sodium aluminate solution to obtain leaching slag and leaching liquid, and (5) carrying out magnetic separation on the leaching slag to obtain magnetite concentrate and tailings. The invention can realize the comprehensive extraction of iron, aluminum and silicon in the high-iron high-silicon bauxite without adding additives, the process has good separation effect on silicon, iron and aluminum, realizes the high-efficiency separation of Al, fe and Si, and the high-efficiency recovery of valuable metals, has less slag discharge amount and good compatibility with the prior process, and is suitable for large-scale industrial treatment of refractory high-iron high-silicon bauxite which cannot be developed and utilized at present.

Inventors

  • WANG HONGYANG
  • LI ZHAO
  • YANG CHENXI
  • WU BINGYAN
  • ZHOU HUILI
  • WANG XIANGYU
  • ZHANG XIAOXUE

Assignees

  • 安徽理工大学

Dates

Publication Date
20260512
Application Date
20260121

Claims (10)

  1. 1. The method for recycling the high-iron high-silicon bauxite is characterized by comprising the following steps of: (1) Grinding the high-iron high-silicon bauxite, and roasting in an oxidizing atmosphere at a temperature of 1000-1200 ℃; (2) Reducing the temperature of the oxidized roasting material to 600-800 ℃ for reduction roasting; (3) Alkaline leaching is carried out on the reduction roasting product to obtain alkaline leaching slag and leaching liquid; (4) Leaching the alkaline leaching residue by adopting a sodium aluminate solution to obtain leaching residue and leaching liquid; (5) And carrying out magnetic separation on the leached slag to obtain magnetite concentrate and tailings.
  2. 2. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein the high-iron high-silicon bauxite comprises, by mass, 20-40% of ferric oxide, 30-55% of aluminum oxide and 10-15% of silicon oxide.
  3. 3. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein in the high-iron high-silicon bauxite, the iron-containing phase comprises one or more of hematite, goethite and goethite; the iron, aluminum and silicon elements in the high-iron high-silicon bauxite mainly exist in a dispersion form, and the main distribution mode of the iron, aluminum and silicon elements in the bauxite is that the iron, aluminum and silicon elements are mutually dispersed.
  4. 4. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein in the step (1), the granularity of the high-iron high-silicon bauxite after grinding is controlled below 200 meshes.
  5. 5. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein in the step (1), the roasting time is 30-120 min, and the oxidizing atmosphere is air.
  6. 6. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein in the step (2), the reduction roasting time is 20-60 min, and the reduction roasting reducing agent is one or more of CO, coke, coal and charcoal.
  7. 7. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein in the step (3), the alkaline leaching time is 30-120 min, the concentration of alkaline liquor is 100-140 g/L, the liquid-solid ratio of the alkaline leaching is 5:1-10:1, and the alkaline liquor is NaOH solution.
  8. 8. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein in the step (4), ρ (Na 2 O k ) =220-240 g/L in the sodium aluminate solution is set to a molar concentration ratio of sodium oxide to aluminum oxide of 2.5-3.0, and the dissolved liquid-solid ratio is 4-6:1.
  9. 9. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein in the step (4), the leaching temperature is 240-260 ℃, and the leaching time is 30-120 min.
  10. 10. The method for recycling high-iron high-silicon bauxite according to claim 1, wherein in the step (5), the intensity of the magnetic separation is controlled to be 500-1500 Gs.

Description

Method for recycling high-iron high-silicon bauxite Technical Field The invention belongs to the technical field of mineral engineering, and particularly relates to a method for recycling high-iron high-silicon bauxite. Background Bauxite resource shortage severely restricts sustainable development of alumina industry in China. A large amount of high-iron high-silicon bauxite exists in regions such as Jiangxi and Guangxi of China, and the bauxite resource can not be effectively developed and utilized at present due to the characteristics of high iron, high silicon and low aluminum. The patent document with publication number of CN117138967A proposes to adopt a flotation process to realize the separation of aluminum and silicon in the high-silicon bauxite, the patent document with publication number of CN106902975A proposes to realize the separation of aluminum and silicon in the high-silicon bauxite by cooperation of gravity separation and flotation, the patent document with publication number of CN116651609A proposes to realize the separation of iron and aluminum in the high-iron bauxite by adopting a physical separation method, the patent document with publication number of CN120575027A proposes to realize the separation of aluminum and iron in the high-iron bauxite by a one-stage digestion-roasting-two-stage digestion process, the patent document with publication number of CN120440918A proposes to bake activation-high-temperature calcification transformation treatment of the high-iron bauxite, the patent document with publication number of CN120311021A proposes to realize the effective separation of iron and aluminum in the high-iron bauxite by acid leaching process, the patent document with publication number of CN118979147A proposes to realize the separation of iron and aluminum in the high-iron bauxite by direct reduction-electric furnace smelting-magnetic separation, and the patent document with publication number of CN107686886A proposes to realize the separation of iron and aluminum in the high-iron bauxite by suspension-roasting. The method is used for singly treating the high-silicon bauxite or the high-iron bauxite, and is difficult to directly treat the high-iron high-silicon bauxite. Patent document with publication number CN103614547a proposes to separate iron, aluminum and silicon in high-iron high-silicon bauxite by roasting-mixed alkaline leaching-magnetic separation, but the recovery rate of iron by the method still needs to be improved. Disclosure of Invention The invention aims to solve the problems in the prior art, and aims to provide a method for recycling high-iron high-silicon bauxite. The method realizes the high-efficiency separation and recovery of silicon, aluminum and iron in refractory ore high-iron high-silicon bauxite, has strong compatibility with the prior art, and has high resource utilization degree and strong economic effect. In order to achieve the above purpose, the invention adopts the following technical scheme: a method for recycling high-iron high-silicon bauxite comprises the following steps: (1) Grinding the high-iron high-silicon bauxite, and roasting in an oxidizing atmosphere at a temperature of 1000-1200 ℃; (2) Reducing the temperature of the oxidized roasting material to 600-800 ℃ for reduction roasting; (3) Alkaline leaching is carried out on the reduction roasting product to obtain alkaline leaching slag and leaching liquid; (4) Leaching the alkaline leaching residue by adopting a sodium aluminate solution to obtain leaching residue and leaching liquid; (5) And carrying out magnetic separation on the leached slag to obtain magnetite concentrate and tailings. Further, in the high-iron high-silicon bauxite, the content of ferric oxide is 20-40% by mass, the content of aluminum oxide is 30-55% by mass, and the content of silicon oxide is 10-15% by mass. Further, in the high-iron high-silicon bauxite, the iron-containing phase comprises one or more of hematite, goethite and goethite, the iron, aluminum and silicon elements in the high-iron high-silicon bauxite mainly exist in a dispersion form, and the iron, aluminum and silicon elements are mainly distributed in the bauxite in a mutually-dispersed mode. Further, in the step (1), the granularity of the high-iron high-silicon bauxite after grinding is controlled below 200 meshes. Further, in the step (1), the roasting time is 30-120 min, and the oxidizing atmosphere is air. Further, in the step (2), the reducing roasting time is 20-60 min, and the reducing agent for reducing roasting is one or more of CO, coke, coal and charcoal. Further, in the step (3), the alkaline leaching time is 30-120 min, the concentration of the alkaline solution is 100-140 g/L, the liquid-solid ratio of the alkaline leaching is 5:1-10:1, and the alkaline solution is a NaOH solution. Further, in the step (4), ρ (Na 2Ok) =220-240 g/L in the sodium aluminate solution, the molar concentration ratio of sodium oxide to aluminum oxide is 2