Method for extracting iron by carrying out suspension magnetizing roasting and cyanide breaking-magnetic separation on high-iron cyanidation tailings

Abstract

The invention provides a method for extracting iron by carrying out suspension magnetizing roasting and cyanide breaking-magnetic separation on high-iron cyanidation tailings. The method comprises thefollowing steps of: (1) crushing and grinding the high-iron cyanidation tailings; (2) introducing the high-iron cyanidation tailings into a pre-oxidation suspension roasting furnace, enabling high-temperature flue gas to enter the pre-oxidation suspension roasting furnace, heating the tailings powder to 650-750 DEG C in a suspension state for cyanide breaking roasting, and removing the residual solid material oxidized slag powder; (3) introducing the oxidized slag powder into a reduction roasting furnace, introducing coal gas and nitrogen into the bottom of the reduction roasting furnace, carrying out reduction roasting on the oxidized slag powder at 500-600 DEG C in a suspension state, and removing the residual reduced slag powder; (4) cooling the reduced slag powder, and then carrying out first-stage ore grinding and first-stage low-intensity magnetic separation; and (5) carrying out second-stage ore grinding and second-stage low-intensity magnetic separation on the first-stage concentrate, wherein the second-stage concentrate is iron concentrate. According to the method, a suspension magnetizing roasting iron extraction and cyanide breaking process is adopted, so that the threat of toxic wastewater generated by wet cyanide breaking to the environmental safety can be eliminated, the process production continuity is good, the process is simple, the application range is wide,and the equipment is easy to realize large-scale and industrialization.

Description

technical field [0001] The invention belongs to the technical field of mineral processing, and in particular relates to a method for suspending, magnetizing and roasting ferricyanide tailings to break cyanide and extract iron by magnetic separation. Background technique [0002] Gold smelting enterprises discharge a large amount of cyanide tailings every year, and their long-term stockpiling not only occupies land, but also pollutes the environment. Cyanide tailings contain valuable metals such as gold, silver, copper, iron, zinc, etc. Among them, the high-ferricyanide tailings TFe grade reaches 30-40%, which is a valuable secondary iron resource. If it cannot be obtained effectively Utilization will cause a waste of resources; but due to the highly toxic cyanide remaining in the cyanide tailings, it is easy to produce cyanide-containing wastewater or waste residues when extracting valuable metals, making it difficult to obtain large-scale utilization; therefore , to develo...

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Problems solved by technology

[0002] Gold smelting enterprises discharge a large amount of cyanide tailings every year, and their long-term storage not only occupies land, but also pollutes the environment

Cyanide tailings contain valuable metals such as gold, silver, copper, iron, zinc, etc. Among them, the high-ferricyanide tailings TFe grade reaches 30-40%, which is a valuable secondary iron resource. If it cannot be obtained effectively Utilization will cause a waste of resources; but due to the highly toxic cyanide remaining in the cyanide tailings, it is easy to produce cyanide-containing wastewater or waste residues when extracting valuable metals, making it difficult to obtain large-scale utilization; therefore , to develop a new technology for the harmless and efficient utilization of ferricyanide tailings, which can not only solve the serious environmental pollution caused by its large amount of stockpiling, but also obtain iron ore resources

[0003] Patent CN201610618637.6 discloses a method for cleaning and converting roasted cyanidation tailings, and proposes to obtain TFe through the method of "first-stage acidification cyanide removal-first-stage dehydration-secondary acidification cyanide removal-secondary dehydration-magnetic separation-wastewater treatment" The iron concentrate with a grade of 55% has realized the clean conversion of roasting cyanidation tailings; but this method consumes a large amount of additives such as sulfuric acid, sodium sulfite, hydrogen peroxide and copper sulfate, as well as a large amount of clean water, and the acidification and oxidation time is as long as 11 More than one hour, there are problems such as high cost, low efficiency, low grade of iron concentrate, and large amount of waste water.

[0004] Patent CN201610129549.X discloses a method for recovering gold, iron, and lead in cyanide tailings, and proposes to use hydrochloric acid to leach iron, lead, and gold in cyanide tailings, and adopts a step-by-step separation method to gradually recover gold, iron, and lead , to realize the recovery of valuable metals; but this method does not point out how to remove the cyanide in the cyanide tailings, and needs to use a large amount of concentrated hydrochloric acid, which takes 1 to 2 hours in the leaching process, and the removal of cyanide is not complete. Concentrated hydrochloric acid is volatile and causes air pollution, and the separation process of gold, iron and lead in the leaching solution is complicated, etc.

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