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:
Nov. 09, 1999
Filed:
Mar. 21, 1997
Balu Sarma, Airmont, NY (US);
Kenneth B Downing, Greenville, SC (US);
Joseph E McGreal, Pittsburgh, PA (US);
Steel Technology Corporation, Washington, DC (US);
Abstract
In order to lower the sulfuric content of the offgas from a smelter reactor in which iron oxide is reduced to molten iron, in the presence of sulfur contaminants, a sufficient amount of a source of zinc is included in the charge to the reactor that the combined weight of the zinc source and the iron oxide source contains at least about 0.6% Zn (calculated as elemental zinc), on a dry weight basis. The temperature of the offgas is maintained at or above approximately 700.degree. C. Vaporized zinc, present in the offgas, binds with sulfur in the offgas to precipitate solid ZnS. After removal of the ZnS, the offgas may have a sulfuric content below 50 ppm by volume of H.sub.2 S equivalent. Suitable sources of zinc include blast furnace dust, electric arc dust, basic oxygen furnace dust, zinc calcine, and zinc sinter.