Treatment of complex sulfide concentrate

Patent metadata

Field	Value
Publication number	US-10501824-B2
Application number	US-201515524708-A
Country	US
Kind code	B2
Filing date	Nov 10, 2015
Priority date	Nov 10, 2014
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

A process of treating complex sulfide concentrate includes the steps of roasting wet or slurried complex sulfide concentrate in a furnace at a temperature of at least 720° C. to obtain a calcine; smelting the calcine under inert or oxygen free atmosphere in a smelting furnace to obtain a matte, and optionally granulating the matte to obtain a granulated matte.

First claim

The invention claimed is:

1. A process of treating complex sulfide concentrate, wherein the complex sulfide ore comprises 2 to 20 wt % Ni, 0 to 15 wt % Cu, and 10 to 55 wt % Fe of the total weight of the concentrate and the complex sulfide concentrate is obtained from complex sulfide ores comprising sulfides of two or more metals, comprising the steps of:
(a) roasting wet or slurried complex sulfide concentrate in a furnace at a temperature from 720° C. to 870° C. to obtain a calcine, wherein oxygen is introduced into the roasting step (a) as oxygen enriched air, wherein the oxygen partial pressure is below 1000 Pa; and
(b) smelting the calcine obtained in step (a) at a temperature from 1250° C. to 1500° C. under inert or oxygen free atmosphere in a smelting furnace to obtain a matte.

2. The process as claimed in claim 1 , further comprising:
(c) granulating the matte obtained in step (b) to obtain a granulated matte.

3. The process as claimed in claim 1 , wherein the complex sulfide concentrate comprises Ni, Cu, Co, Fe and/or PGM.

4. The process as claimed in claim 1 , wherein the calcine has sulfur content below 10% w/w.

5. The process as claimed in claim 1 , wherein the furnace in step (a) is a drum furnace or a fluidizing bed furnace.

6. The process as claimed in claim 1 , wherein the roasting temperature in step (a) is from 780 to 820° C.

7. The process as claimed in claim 1 , wherein roasting in step (a) is accomplished in a bubbling bed.

8. The process as claimed in claim 1 , wherein the smelting temperature in step (b) is from 1300 to 1450° C.

9. The process as claimed in claim 1 , wherein a first part of the complex sulfide concentrate is introduced into the roasting step (a) and a remaining second part is introduced into the smelting step (b) after drying.

10. The process as claimed in claim 1 , wherein the smelting furnace is an electric furnace.

11. The process as claimed in claim 1 , wherein the roasting temperature in step (a) is from 750 to 850° C.

Assignees

• Outotec Finland Oy

Inventors

• Metsärinta Maija-Leena
• Jyrkönen Satu
• Liipo Jussi

Classifications

• C22B23/025 Primary

  with formation of a matte or by matte refining or converting into nickel or cobalt, e.g. by the Oxford process (leaching of mattes C22B23/04) · CPC title

• C22B23/005

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

• C22B15/0015

  Oxidizing roasting · CPC title

• C22B5/08 Primary

  by sulfides; Roasting reaction methods · CPC title

• C22B15/0028

  Smelting or converting · CPC title