| 摘要 |
A method for producing hematite is provided, which firstly enables Ca-based neutralizers and parent-rock-derived neutralizers other than Ca-based neutralizers to be used in actual operations for refining, from a fine iron oxide-containing leaching residue produced by a HPAL process, hematite having a sulfur component sufficiently low to be capable of being used as an iron-production starting material, and which secondly enables sintering of extremely fine ore that is not capable of being conventionally used. This method for producing (highly pure) hematite for iron production, in a process in which a mineral acid and an oxidizer are added to ore including iron and a valuable metal to leach the valuable metal under high temperature and high pressure, is characterized by including steps (1)-(9), namely a high pressure leaching step (1), a preliminary neutralization step (2), a first solid-liquid separation step (3), a first neutralization step (4), a second neutralization step (5), a third solid-liquid separation step (6), a seed-crystal addition step (7), a second solid-liquid separation step (8), and a sintering step (9). |
