Sumitomo Metal Mining Company, Ltd.

Hochiki Corporation

Manabu Enomoto

Yoshitomo Ozaki

Hiroyuki Mitsui

Tatsuya Higaki

Hirofumi Shouji

Hideki Sasaki

Hayato Tsurumi

Tomoaki Yoneyama

Yasumasa Kan

Hirofumi Shoji

Fire alarm

Provided is a method for manufacturing a nickel and cobalt mixed sulfide that is capable of stabilizing nickel and cobalt concentrations in the sulfidation end solution at low levels and of limiting decreases in nickel and cobalt recovery rates without increasing cost even when processing with a sulfuric acid acidic solution containing nickel and cobalt and a high iron ions concentration as the sulfidation start solution. This method generates a sulfidation reaction by blowing hydrogen sulfide gas into a sulfuric acid acidic solution comprising nickel and cobalt to obtain a mixed sulfide, wherein: the sulfuric acid acidic solution, which is the sulfidation start solution, contains iron ions at a rate of 1.0-4.0 g/L; and the sulfidation reaction is generated by blowing hydrogen sulfide gas into the sulfidation start solution and adding sodium hydrogensulfide (NaHS) obtained by absorbing hydrogen sulfide gas-containing exhaust gas, generated by the sulfidation, in an alkaline solution.

Method for manufacturing nickel and cobalt mixed sulfide and nickel oxide ore hydrometallurgical method

Provided is a production method for refining iron oxide (hematite), which has such a low sulfur content as to be used as an iron-making raw material, from a leach residue containing iron oxide produced by a high pressure acid leach (HPAL) process. In the method for refining iron oxide for ironmaking by a process of adding sulfuric acid to nickel oxide ore and then leaching nickel from the nickel oxide ore using a pressure vessel, an amount of the sulfuric acid added is 150 kg or more and 220 kg or less per ton of nickel oxide ore.

Method for producing hematite for ironmaking

Provided is a method for producing hematite for ironmaking, wherein high purity hematite, which can be used as an iron-making raw material, is cheaply and efficiently recovered from a leach residue containing iron oxide produced by a high pressure acid leach (HPAL) process. This method for producing (high purity) hematite for ironmaking in a process of adding a mineral acid and an oxidant to ore containing iron and valuable metals and then leaching the valuable metals under high pressure and high temperature includes (1) a neutralization step of adding a neutralizer to a leachate obtained under high pressure and high temperature to form a leach slurry, (2) a solid-liquid separation step of separating the leach slurry obtained in the neutralization step (1) into a leach residue and the leachate, and (3) a classification step of classifying the leach residue into the hematite and gangue components.

Growing community of inventors

Niihama, Japan

Manabu Enomoto