Method for producing pellet and method for smelting nickel oxide ore

Patent metadata

Field	Value
Publication number	US-2017152584-A1
Application number	US-201515325515-A
Country	US
Kind code	A1
Filing date	Jun 30, 2015
Priority date	Jul 15, 2014
Publication date	Jun 1, 2017
Grant date	—

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

1 . A method for producing pellets from nickel oxide ore, comprising
conducting heat treatment to heat a lump made by forming the nickel oxide ore into a lump shape at a temperature of 350° C. to 600° C.

2 . The method for producing pellets according to claim 1 , wherein the lump is heated at a temperature of 400° C. to 550° C. in the heat treatment.

3 . The method for producing pellets according to claim 1 , wherein a preliminarily heat treatment is conducted on the lump prior to conducting the heat treatment on the lump.

4 . The method for producing pellets according to claim 3 , wherein the lump is preliminarily heated by holding at a temperature of 100° C. to 170° C. for at least two hours in the preliminary heat treatment.

5 . A method for smelting nickel oxide ore, comprising:
a pellet production step of producing pellets from the nickel oxide ore; and a reduction step of heating the pellets obtained at a predetermined reduction temperature in a reducing furnace, wherein a pellet is produced in the pellet production step by conducting heat treatment that heats a lump made by forming the nickel oxide ore in a lump shape at a temperature of 350° C. to 600° C.

6 . The method for smelting nickel oxide ore according to claim 5 , 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.

7 . The method for producing pellets according to claim 2 , wherein a preliminarily heat treatment is conducted on the lump prior to conducting the heat treatment on the lump.

8 . The method for producing pellets according to claim 7 , wherein the lump is preliminarily heated by holding at a temperature of 100° C. to 170° C. for at least two hours in the preliminary heat treatment.

Assignees

• Sumitomo Metal Mining Co

Inventors

• Takahashi Junichi
• Inoue Taku
• Okada Shuuji

Classifications

• C22C33/04

  by melting · CPC title

• C22B5/10

  by solid carbonaceous reducing agents · CPC title

• C22B1/2413

  enduration of pellets · CPC title

• C22B23/02 Primary

  by dry processes · CPC title

• C22B23/005

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