Method of making pig iron with zinc recovery
AssigneeHoogovens Staal BV
InventorsJohannes G. Bernard, Hendrikus K. A. Meijer, Cornelis P. Teerhuis
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Abstract
A method making pig iron employs an in-bath direct reduction performed in a metallurgical vessel which has above it a melting cyclone in which iron-oxide-containing material fed thereinto is pre-reduced by hot reducing gas coming from the vessel. Molten material passes downwardly from the melting cyclone into the vessel. In order to recover zinc from a dust containing zinc and/or zinc oxide, the dust is fed into the melting cyclone. Zinc is allowed to vaporize out of the dust into the hot gas in the melting cyclone. The hot gas containing zinc is discharged from the melting cyclone, and zinc-containing material is extracted from this hot gas.
Claims10
A method of making pig iron, with recovery of zinc, comprising the steps of:
- 1) producing pig iron by an in-bath direct reduction process performed in a metallurgical vessel, said direct reduction process providing a hot reducing gas,
- ii) performing a pre-reduction of iron-oxide-containing material in a melting cyclone located above said metallurgical vessel, by feeding said iron-oxide-containing material into said melting cyclone and allowing said hot reducing gas to pass from said metallurgical vessel upwardly into said melting cyclone, while allowing molten material pre-reduced in said melting cyclone to pass downwardly into said metallurgical vessel, said iron-oxide-containing material comprising a dust containing at least one of zinc and zinc oxide,
- iii) allowing zinc to vaporize out of said dust in said melting cyclone,
- iv) discharging hot gas containing zinc from said melting cyclone, and
- v) extracting zinc-containing material from said hot gas discharged from said melting cyclone.
Dependencies are inferred from the claim text.