Method for refining sulfidic copper concentrate

Patent metadata

Field	Value
Publication number	US-10435769-B2
Application number	US-201916247900-A
Country	US
Kind code	B2
Filing date	Jan 15, 2019
Priority date	Jul 22, 2016
Publication date	Oct 8, 2019
Grant date	Oct 8, 2019

Abstract

A method for refining sulfidic copper concentrate includes feeding sulfidic copper concentrate and oxygen-bearing reaction gas and slag forming material into a reaction shaft of a suspension smelting furnace, collecting slag and blister copper in a settler of the suspension smelting furnace to form a blister layer containing blister copper and a slag layer, and discharging slag and blister copper separately from the settler of the suspension smelting furnace, so that slag is fed into an electric furnace. The method further includes feeding a part of the sulfidic copper concentrate into the electric furnace.

First claim

The invention claimed is:

1. A method for refining sulfidic copper concentrate, the method comprising:
feeding a first portion of sulfidic copper concentrate and oxygen-bearing reaction gas and slag forming material into a reaction shaft of a suspension smelting furnace by means of a burner that is arranged on top of the reaction shaft of the suspension smelting furnace, whereby sulfidic copper concentrate and oxygen-bearing reaction gas and slag forming material react in the reaction shaft of the suspension smelting furnace into blister copper and slag;
collecting slag and blister copper in a settler of the suspension smelting furnace to form a blister layer containing blister copper and a slag layer containing slag on top of the blister layer;
discharging slag in an unreduced state and blister copper separately from the settler of the suspension smelting furnace, so that slag in an unreduced state is fed into an electric furnace;
feeding a second portion of sulfidic copper concentrate into the electric furnace;
reducing the slag that is fed in the unreduced state from the suspension smelting furnace in the electric furnace at least partly with the second portion of sulfidic copper concentrate that is fed into the electric furnace to form a matte layer containing copper matte and an electric furnace slag layer containing electric furnace slag on top of the matte layer;
discharging electric furnace slag and matte copper separately from the electric furnace;
granulating and treating the copper matte that is discharged from the electric furnace to obtain copper matte feed material; and
feeding at least a part of the copper matte feed material into the reaction shaft of the suspension smelting furnace by means of the burner.

2. The method according to claim 1 , further comprising:
feeding blister copper from the settler of the suspension smelting furnace into an anode furnace;
fire refining the blister copper in the anode furnace.

3. The method according to claim 1 , further comprising:
subjecting the electric furnace slag to a final slag treatment process to form reject and slag concentrate or other copper containing product; and
feeding the slag concentrate or other copper containing product by means of the burner into the reaction shaft of the suspension smelting furnace.

4. The method according to claim 1 , further comprising:
feeding a carbon containing reducing agent into the electric furnace, wherein the carbon containing reducing agent is coke.

5. The method according to claim 1 , further comprising:
feeding process gases from an uptake of the suspension smelting furnace to a process gas treatment arrangement.

6. The method according to claim 1 , further comprising:
feeding process gases from the electric furnace to a process gas treatment arrangement.

7. The method according to claim 1 , wherein the second portion of sulfidic copper concentrate that is fed into the electric furnace includes between 5 and 50% of the total amount of sulfidic copper concentrate, the total amount of sulfidic copper concentrate comprising the first and second portions of sulfidic copper concentrate.

8. The method according to claim 1 , wherein the second portion of sulfidic copper concentrate that is fed into the electric furnace includes between 10 and 40% of the total amount of sulfidic copper concentrate, the total amount of sulfidic copper concentrate comprising the first and second portions of sulfidic copper concentrate.

9. The method according to claim 1 , wherein the second portion of sulfidic copper concentrate that is fed into the electric furnace includes between 25 and 35% of the total amount of sulfidic copper concentrate, the total amount of sulfidic copper concentrate comprising the first and second portions of sulfidic copper concentrate.

10. The method according to claim 1 , wherein the mass ratio of the second portion of the sulfidic copper concentrate that is fed into the electric furnace to slag that is fed into the electric furnace is smaller than 1 to 1.

11. The method according to claim 10 , wherein the mass ratio of the second portion of the sulfidic copper concentrate that is fed into the electric furnace to slag that is fed into the electric furnace is between 0.25 to 1 and 0.7 to 1.

12. The method according to claim 10 , wherein the mass ratio of the second portion of the sulfidic copper concentrate that is fed into the electric furnace to slag that is fed into the electric furnace is between 0.25 to 1 and 0.7 to 1.

13. The method according to claim 1 , wherein the moisture content of the second portion of the sulfidic copper concentrate that is fed into the electric furnace is below 1% by weight.

14. The method according to claim 1 , wherein the moisture content of the second portion of the sulfidic copper concentrate that is fed into the electric furnace is below 0.5% by weight.

15. The method according to claim 1 , wherein the moisture content of the first portion of the sulfidic copper concentrate that is fed into the reaction shaft of the suspension smelting furnace is below 1% by weight.

16. The method according to claim 1 , wherein the moisture content of the first portion of the sulfidic copper concentrate that is fed into the reaction shaft of the suspension smelting furnace is below 0.5% by weight.

17. The method according to claim 1 , wherein the second portion of the sulfidic copper concentrate that is fed into the electric furnace includes about 33% of the total amount of sulfidic copper concentrate, the total amount of sulfidic copper concentrate comprising the first and second portions of sulfidic copper concentrate.

Assignees

• Outotec Finland Oy

Inventors

• Jaatinen Akusti

Classifications

• C22B5/08

  by sulfides; Roasting reaction methods · CPC title

• C22B15/0052

  Reduction smelting or converting · CPC title

• C22B15/0047

  flash smelting or converting · CPC title

• C22B15/0054 Primary

  Slag, slime, speiss, or dross treating · CPC title

• C22B15/0028 Primary

  Smelting or converting · CPC title