Production method for hematite for iron production

摘要

Provided is a production method in which iron oxide (hematite) having a sulfur content that is low enough to make it possible to use said iron oxide as a starting material for iron production is purified from a leaching residue containing iron oxide that is produced in an HPAL process. The production method for (highly pure) hematite for iron production is for use in a process in which an oxidizing agent and sulfuric acid are added to a nickel oxide ore and nickel is leached, and is characterized in that: a neutralizing agent that reacts with the free sulfuric acid of excess acid that is included in a leached slurry and produces gypsum is added to a leached slurry in which a leachate and a leach residue that are obtained after leaching nickel are mixed; solid/liquid separation is subsequently performed; a neutralization residue having a sulfur grade that is greater than 1.0 wt% is formed; the neutralization residue is heat treated at a heating temperature of 600-1400 °C; and hematite having a sulfur grade of 1.0 wt% or less is formed.