Method for producing pellet and method for smelting nickel oxide ore

Patent metadata

Field	Value
Publication number	US-10323297-B2
Application number	US-201515325515-A
Country	US
Kind code	B2
Filing date	Jun 30, 2015
Priority date	Jul 15, 2014
Publication date	Jun 18, 2019
Grant date	Jun 18, 2019

Abstract

Provided is a method for producing a pellet capable of suppressing heat shock-induced crack occurrence, when nickel oxide ores are made into pellets and placed in a reducing furnace in a smelting process. In the method for producing a pellet from a nickel oxide ore, a nickel oxide ore, a binder and a carbonaceous reducing agent are mixed, the mixture is made into a lump, and then the resulting lump is subjected to a preheat treatment at a temperature of 350° C. to 600° C. In this preheat treatment, the lump more preferably undergoes the preheat treatment at a temperature of 400° C. to 550° C.

First claim

The invention claimed is:

1. A method for producing pellets on the order of 10 to 30 mm in size from nickel oxide ore, comprising:
conducting a preliminarily heat treatment to heat a lump made by forming the nickel oxide ore into a lump shape at a temperature of 100° C. to 170° C., and then
conducting heat treatment to heat the lump after conducting the preliminary heat treatment at a temperature of 450° C. to 600° C.

2. The method for producing pellets according to claim 1 , wherein the lump is preliminarily heated by holding for at least two hours in the preliminary heat treatment.

3. A method for smelting nickel oxide ore, comprising:
a pellet production step of producing pellets on the order of 10 to 30 mm in size from the nickel oxide ore; and
a reduction step of heating the pellets produced at a predetermined reduction temperature in a reducing furnace,
wherein a pellet is produced in the pellet production step by
conducting a preliminary heat treatment that heats a lump made by forming the nickel oxide ore into a lump shape at a temperature of 100° C. to 170° C., and then
conducting heat treatment that heats the lump after conducting the preliminary heat treatment at a temperature of 450° C. to 600° C.

4. The method for smelting nickel oxide ore according to claim 3 , wherein, after conducting heat treatment on the lump to make a pellet in the pellet production step, the pellet is loaded into the reducing furnace in a state retaining the temperature of the heat treatment.

Assignees

• Sumitomo Metal Mining Co

Inventors

• Takahashi Junichi
• Inoue Taku
• Okada Shuuji

Classifications

• C22B1/2406

  pelletizing · CPC title

• C22C33/04

  by melting · CPC title

• C22B23/005

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

• C22B23/02 Primary

  by dry processes · CPC title

• C22B5/10

  by solid carbonaceous reducing agents · CPC title