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. 28, 2017
Filed:
Dec. 12, 2013
Sumitomo Metal Mining Co., Ltd., Tokyo, JP;
SUMITOMO METAL MINING CO., LTD., Tokyo, JP;
Abstract
Provided is a method for producing hematite for ironmaking, capable of using a conventional Ca-based neutralizing agent and a base rock-derived neutralizing agent other than the Ca-based neutralizing agent. The method is performed by a process of adding a mineral acid and an oxidizing agent to an ore containing iron and a valuable metal and then leaching the valuable metal under high temperature and pressure, and includes (1) a high-pressure acid leaching step, (2) a preliminary neutralization step, (3) a first solid-liquid separation step, (4) a neutralization step, (5) a second neutralization step, (6) a third solid-liquid separation step, (7) a step of adding part of the Fe-enriched slurry as a seed crystal in the neutralization step (4), and (8) a second solid-liquid separation step.