Method for recovering chromite, and method for wet smelting of nickel oxide ore

Patent metadata

Field	Value
Publication number	US-9068244-B2
Application number	US-201214384616-A
Country	US
Kind code	B2
Filing date	Apr 6, 2012
Priority date	Apr 6, 2012
Publication date	Jun 30, 2015
Grant date	Jun 30, 2015

Abstract

A method for recovering chromite from ore slurry obtained by processing nickel oxide ore, the raw material, in a plant for the wet smelting of nickel oxide ore. In the method chromite is separated and recovered from an ore slurry obtained from a nickel oxide ore when nickel and cobalt are recovered from the nickel oxide ore. The method has a grain diameter separation step for separating the ore slurry on the basis of a predetermined classification point according to the difference in the grain diameter of particles contained in the supplied ore slurry and a sedimentation separation step for causing the oversized ore slurry separated in the grain diameter separation step to undergo sedimentation and concentration on the basis of a target classification point, and recovering the chromite. The coarse particle content of the oversized ore slurry separated in the grain diameter separation step is adjusted to 30-50%.

First claim

The invention claimed is:

1. A chromite recovery method for separating and recovering chromite from ore slurry produced from nickel oxide ore when recovering nickel and cobalt from the nickel oxide ore, the method comprises:
a particle diameter separation step of separating the ore slurry which has a particle size of 2 mm or less based on a predetermined classification point depending on a particle diameter difference of particles contained in the ore slurry to be supplied; and
a sedimentation separation step of sedimenting and concentrating oversized ore slurry separated in the particle diameter separation step to recover the chromite,
wherein a content percentage of coarse particles in the oversized ore slurry separated in the particle diameter separation step is adjusted to 30 to 50%.

2. The recovery method for chromite according to claim 1 , wherein a concentration of ore slurry supplied to the particle diameter separation step is 10% by weight.

3. A hydrometallurgical process for nickel oxide slurry for transporting ore slurry produced by slurrying nickel oxide ore to a high pressure acid leach facility where nickel and cobalt are leached to recover the nickel and cobalt from leachate produced by solid-liquid separation leached slurry, the process comprises:
a chromite recovery step including:
a particle diameter separation step of separating the ore slurry which has a particle size of 2 mm or less based on a classification point depending on a particle diameter difference of particles contained in the ore slurry; and
a sedimentation separation step of sedimenting and concentrating oversized ore slurry separated in the particle diameter separation step based on a target classification point to recover chromite,
wherein a content percentage of coarse particles in the oversized ore slurry separated in the particle diameter separation step is adjusted to 30 to 50%.

Assignees

• Mitsui Hiroyuki
• Nakai Osamu
• Kawasaki Hirotaka
• Kobayashi Hiroshi
• Higaki Tatsuya
• Idegami Atsushi
• Sumitomo Metal Mining Co

Inventors

• Mitsui Hiroyuki
• Nakai Osamu
• Kawasaki Hirotaka
• Kobayashi Hiroshi
• Higaki Tatsuya
• Idegami Atsushi

Classifications

• C22B23/005 Primary

  Preliminary treatment of ores, e.g. by roasting or by the Krupp-Renn process · CPC title

• C22B3/22 Primary

  by physical processes, e.g. by filtration, by magnetic means {, or by thermal decomposition} (treatment or purification of solutions by liquid-liquid extraction C22B3/26) · CPC title

• C22B23/04

  by wet processes (recovery or separation of nickel or cobalt using organic agents C22B3/00) · CPC title

• B03B7/00

  Combinations of wet processes or apparatus with other processes or apparatus, e.g. for dressing ores or garbage · CPC title

• C22B23/043

  Sulfurated acids or salts thereof · CPC title