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:
Feb. 13, 2018
Filed:
Sep. 04, 2014
Sumitomo Metal Mining Co., Ltd., Tokyo, JP;
SUMITOMO METAL MINING CO., LTD., Tokyo, JP;
Abstract
A method of producing (high-purity) hematite for ironmaking includes adding an oxidant and sulfuric acid to nickel oxide ore and then leaching nickel. The method further includes forming a neutralized residue having a sulfur grade exceeding 1.0% by weight by adding a neutralizing agent to leach slurry and being subjected to solid-liquid separation. The neutralizing agent functions to form plaster by reaction with a free sulfuric acid of surplus acid contained in the leach slurry. The leach slurry is a mixture of a leachate and a leach residue obtained after leaching the nickel. The method then includes heating the neutralized residue at a heating temperature of 600° C. or more and 1400° C. or less to form hematite having a sulfur grade of 1.0% or less by weight.