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:
Mar. 20, 2007
Filed:
Apr. 30, 2004
Tetsuharu Ibaraki, Chiba, JP;
Takashi Hiromatsu, Chiba, JP;
Satoshi Kondo, Chiba, JP;
Shoji Imura, Chiba, JP;
Yoichi Abe, Chiba, JP;
Tetsuharu Ibaraki, Chiba, JP;
Takashi Hiromatsu, Chiba, JP;
Satoshi Kondo, Chiba, JP;
Shoji Imura, Chiba, JP;
Yoichi Abe, Chiba, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
The present invention provides a reducing furnace of the rotary hearth-type and a method for reducing a metal oxide simplified in the process from dehydration to molding, according to which a moisture-rich powdery raw material is reduced at low cost. The present invention also provides an operation method whereby dusts or sludge generated in the refining or processing of metal are economically recycled. A powdery mixture having a moisture content of 100% or higher relative to the total mass of a metal oxide-containing powder and a carbon-containing powder is made into a slurry and mixed by stirring. Thereafter, the slurry is dehydrated to a moisture content of 16 to 26% and compression-molded into articles. The cylindrical or granular shaped articles having a thickness or diameter of 30 mm or less thus obtained are fed to a zone the atmospheric temperature of which is 1170° C. or lower in the furnace and reduced through calcination by a rotary hearth reducing furnace thereby to provide a metal.