The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 19, 1999
Filed:
Apr. 13, 1998
Huibert W den Hartog, Noordwijkerhout, NL;
Hendrikus K Meijer, Uitgeest, NL;
Hoogovens Staal BV, Ijmuiden, NL;
Abstract
A process for producing molten pig iron uses direct reduction of iron ore in a pre-reduction stage followed by a final reduction stage. In the pre-reduction stage iron ore is pre-reduced in a melting cyclone by means of a reducing process gas originating from the final reduction stage. A post-combustion occurs in the reducing process gas in the melting cyclone so that said iron ore in said melting cyclone is at least partly melted. The partly melted iron ore passes downwardly into a metallurgical vessel situated beneath the cyclone in which the final reduction takes place by supply of coal and oxygen, thereby forming a reducing process gas. A partial post-combustion occurs in the reducing process gas in the metallurgical vessel by means of said oxygen supplied thereto. The post-combustion ratio of the gas on exiting the metallurgical vessel is not more than 0.55. The coal is supplied directly into the slag layer so that said partial post-combustion in said metallurgical vessel is at least partly effected in the slag layer.