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:
Jul. 04, 1989
Filed:
Dec. 18, 1987
Yotaro Oono, Tokyo, JP;
Hiroshi Saito, Tokyo, JP;
Takehiko Miyamoto, Tokyo, JP;
Kazumasa Wakimoto, Tokyo, JP;
Hitoshi Kawada, Tokyo, JP;
Masahiro Matsuura, Tokyo, JP;
Nippon Kokan Kabushiki Kaisha, Tokyo, JP;
Abstract
A method for operating a blast furnace, comprising the steps: charging iron ores and cokes through a furnace top into the blast furnace; blowing in gas containing 40 vol. % or more oxygen together with pulverized coal through tuyeres into the blast furnance; and controlling a fuel ratio within a range of 500 to 930 kg/ton., molten pig iron and still a ratio of the pulverized coal blown in through the tuyeres within a range satisfying the formula: ##EQU1## molten pig iron, where X represents a fuel ratio. Through blown-in inlets set in the furnace shaft, preheating gas is blown in to preheat burdens. The cokes charged into the blast furnace are cokes of low strength having a drum index of DI.sub.15.sup.30 of 80 to 90% .