Method for smelting nickel oxide ore

Patent metadata

Field	Value
Publication number	US-2017306444-A1
Application number	US-201515517046-A
Country	US
Kind code	A1
Filing date	Sep 15, 2015
Priority date	Oct 6, 2014
Publication date	Oct 26, 2017
Grant date	—

Abstract

A smelting method capable of obtaining an iron-nickel alloy having a high nickel grade of 4% or higher by effectively facilitating a reduction reaction of pellets formed using a nickel oxide ore as a raw material. The present invention is a method for smelting a nickel oxide ore, by which an iron-nickel alloy is obtained by forming pellets from a nickel oxide ore and reducing and heating the pellets. In the pellet production step S 1 , a mixture is obtained by mixing raw materials that contain at least a nickel oxide ore and a carbonaceous reducing agent. In the reduction step S 2 , a furnace floor carbonaceous reducing agent is laid on the floor of the smelting furnace in advance when placing the obtained pellets in the smelting furnace and the pellets are placed on the furnace floor carbonaceous reducing agent and then reduced and heated.

First claim

1 . A method for smelting nickel oxide ore, in which a pellet is formed from the nickel oxide ore, and the pellet is heat-reduced to obtain an iron-nickel alloy with a nickel grade of 4% or more, the method comprising:
a pellet production step for producing a pellet from the nickel oxide ore, and a reduction step for heat-reducing the resulting pellet in a smelting furnace, the pellet production step comprising mixing raw materials containing at least the nickel oxide ore and a carbonaceous reducing agent to obtain a mixture, and agglomerating the mixture to form a pellet, and the reduction step comprising pre-covering the furnace floor of the smelting furnace with a furnace floor carbonaceous reducing agent before charging the resulting pellet into the smelting furnace, and performing reduction heat treatment with the pellet loaded onto the furnace floor carbonaceous reducing agent.

2 . The method for smelting nickel oxide ore according to claim 1 , wherein
the reduction step comprises heat-reducing the pellet loaded onto the furnace floor carbonaceous reducing agent at a heating temperature of 1350° C. or more and 1550° C. or less.

3 . The method for smelting nickel oxide ore according to claim 1 , wherein
the temperature when the pellet is charged into the smelting furnace is 600° C. or less.

4 . The method for smelting nickel oxide ore according to claim 1 , wherein, in the pellet production step,
the mixed amount of the carbonaceous reducing agent is adjusted so that the amount of carbon is 70% or more and 200% or less when the total combined value of a chemical equivalent required for reducing nickel oxide contained in the resulting pellet into nickel metal and a chemical equivalent required for reducing ferric oxide contained in said pellet into ferrous oxide is taken as 100%.

5 . The method for smelting nickel oxide ore according to claim 1 , wherein,
in the reduction step, the time between the start of the reduction heat treatment and the removal of the pellet from the smelting furnace is less than 30 minutes.

Assignees

• Sumitomo Metal Mining Co

Inventors

• Takahashi Junichi
• Inoue Taku
• Okada Shuuji

Classifications

• C22C38/08

  containing nickel {(C22C38/105 takes precedence)} · CPC title

• C22B23/023 Primary

  with formation of ferro-nickel or ferro-cobalt · CPC title

• C22B1/244

  organic · CPC title

• C21B13/006

  Starting from ores containing non ferrous metallic oxides · CPC title

• C22B23/02

  by dry processes · CPC title