Process for recovering iron and zinc from steel making dusts
OwnerFrank M. Stephens, Jr., James C. Blairinventors
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Abstract
The object of the invention is to provide a process for the recovery of iron and zinc from steel making flue dust. The process comprises subjecting the flue dust to a carbiding step in a fluid bed in the presence of a reducing agent and a carbon supplying agent to break down the zinc ferrite structure and convert the iron to iron carbide, followed by heating the residue or product of the carbiding step to recover zinc by evaporization. The iron carbide produced may be introduced into a steel making furnace for the production of steel. An alternative procedure is the recovery of iron carbide and zinc by magnetic separation from the gangue after the carbiding step and before separation of zinc from iron carbide.
Claims20
A process for the recovery of zinc and iron carbide from a material containing zinc and iron which comprises:
- (a) first subjecting the material to a carbiding step to convert a major portion of the iron to iron carbide, and
- (b) subsequently recovering zinc from the product of step (a) leaving a residue containing substantially all the iron carbide.
A process for the recovery of iron and zinc from flue dust which comprises:
- (a) subjecting the flue dust to a carbidizing step in a fluidized bed in the presence of a reducing agent and a carbon supplying agent to convert a major portion of the iron to iron carbide;
- (b) heating the carbidized mixture of step (a) to recover the zinc by vaporization;
- and
- (c) making steel from the product resulting from step (b).
A process for the recovery of iron carbide and a metal having a vaporization point above about 1300.degree. F. from a mixture of iron and the metal which comprises:
- (a) subjecting the mixture to a carbidizing step to convert a major portion of the iron in the mixture to iron carbide;
- and
- (b) recovering iron carbide and said metal from the product of step (a).
A process for the recovery of iron and zinc from zinc ferrite, the recovered iron being suitable for making steel without further refining, the process comprising:
- (a) breaking down the ferrite structure and converting the iron to iron carbide by heating the ferrite in a fluidized bed in the presence of a reducing agent and a carbon supplying material to a temperature not in excess of about 750.degree. C., and
- (b) separating zinc from the residue of step (a) by distillation to leave an iron carbide product which is suitable for making steel without refining.
A process for the recovery of zinc and iron carbide from a material containing zinc and iron which comprises:
- (a) subjecting the mixture to a carbiding step to convert the iron to iron carbide;
- (b) separating the iron carbide and zinc from the gangue of the product by magnetic separation;
- and
- (c) recovering zinc from the product of step (b).
Dependencies are inferred from the claim text.