Method and system for comprehensive recovery and utilization of copper-nickel sulfide ore

Patent metadata

Field	Value
Publication number	US-2019352740-A1
Application number	US-201916529729-A
Country	US
Kind code	A1
Filing date	Aug 1, 2019
Priority date	Apr 10, 2017
Publication date	Nov 21, 2019
Grant date	—

Abstract

The present invention relates to the field of ore smelting technology, and particularly provides a method and system for comprehensive recovery and utilization of copper-nickel sulfide ore. Under normal pressure, the method can be used to directly leach copper-nickel sulfide ore concentrate or low-grade nickel matte obtained by matte smelting of copper-nickel sulfide ore. In the leaching process, the leaching rate of nickel, cobalt and iron is up to 99% or more, and copper is hardly leached, whereby the deep separation of copper from elements such as nickel and cobalt is directly realized, and the huge system for copper-nickel separation in the conventional process is omitted. Moreover, noble metals are not leached, and almost all of them remain in the leaching slag with copper, so the destiny is simple.

First claim

What is claimed is:

1 . A method for comprehensive recovery and utilization of copper-nickel sulfide ore, comprising the following steps:
1) selective leaching, comprising: obtaining a nickel-iron-cobalt-enriched leachate and a copper-enriched leaching slag by selective leaching, wherein the selective leaching is a method for recovering the main accompanying elements from copper-nickel sulfide ore, which comprises the following selective leaching steps: selectively leaching by continuously adding low-grade nickel matte obtained by matte smelting of copper-nickel sulfide ore and a leaching reaction solution to a reaction base liquid, and collecting gaseous hydrogen sulfide, a first leachate, and a first leaching slag respectively, wherein the reaction base liquid is a 20-60 wt % sulfuric acid solution, and the leaching reaction solution is a 60-95 wt % sulfuric acid solution; and adding water to dissolve the first leaching slag, and collecting a second leachate and a second leaching slag respectively, wherein the second leachate is a nickel-iron-cobalt-enriched leachate; and the second leaching slag is a copper-enriched leaching slag; 2) removing iron from the nickel-iron-cobalt-enriched leachate obtained in the step 1), and collecting an iron removed liquid and an iron residue respectively, wherein the iron removed liquid is used for the extraction of nickel and cobalt, and the iron residue is used for iron making; and/or smelting the copper-enriched leaching slag obtained in the step 1) in a copper smelting system to obtain copper and noble metals, respectively.

2 . The method according to claim 1 , wherein in the step 1), the selective leaching is atmospheric non-oxidative leaching; and/or
the leaching reaction solution is a 85-90 wt % sulfuric acid solution.

3 . The method according to claim 1 , wherein in the step 1), the low-grade nickel matte and the leaching reaction solution are continuously added concurrently, and the amounts added are the same as the consumption; and the first leachate is returned back and recycled as a reaction base liquid for the next batch of materials.

4 . The method according to claim 1 , wherein in the step 1), the leaching is continued for 0.5-2 h, after the completion of the feed.

5 . The method according to claim 1 , wherein the sulfur dioxide generated in the matte smelting is reacted with the gaseous hydrogen sulfide generated in the step 1) to prepare sulfur, and the remaining sulfur dioxide is converted into a sulfuric acid solution for use in the atmospheric selective leaching in the step 1).

6 . The method according to claim 1 , wherein in the step 2), the iron removal from the leachate is specifically:
introducing an oxygen-rich gas into the nickel-iron-cobalt-enriched leachate or the nickel-iron-cobalt-enriched leachate having a pH adjusted to 3 to 7, to obtain an iron removed liquid and an iron residue; or adding the nickel-iron-cobalt-enriched leachate to an autoclave and reacting with an oxidizing gas, after the reaction is completed, performing solid-liquid separation, wherein the filter residue is washed and dried to obtain an iron residue; and the obtained filtrate is an iron removed liquid.

7 . The method according to claim 1 , wherein the use of the iron removed liquid for the extraction of nickel and cobalt comprises specifically:
adjusting the pH of the iron removed liquid to 4.0-5.5, and then adding an extracting agent to the iron removed liquid, obtaining a cobalt-containing solution and a nickel-containing solution after extraction and separation, adjusting the nickel-containing solution to pH 5.5-7.0, and extracting nickel with the extracting agent, wherein the extracting agent is a 10-50 vol % solution of P507 or Cyanex 272 in kerosene.

8 . The method according to claim 1 , wherein the method for recovering copper and noble metals specifically comprises:
subjecting the copper-enriched leaching slag obtained by treating the low-grade nickel matte to matte converting to produce crude copper, which is then electrolyzed to obtain refined copper and an anode slime enriched with noble metals respectively, wherein the anode slime is used for extracting noble metals; or subjecting the copper-enriched leaching slag obtained by treating the low-grade nickel matte to oxidizing roasting and then to acid leaching, to collect a copper-enriched leachate and a noble metal-enriched leaching slag separately, wherein the leaching slag is used for extracting noble metals; or subjecting the copper-enriched leaching slag obtained by treating the low-grade nickel matte to oxygen pressure leaching, to collect a copper-enriched leachate and a noble metal-enriched leaching slag separately, wherein the leaching slag is used for extracting noble metals.

9 . A system for implementing the method according to claim 1 , comprising:
a unit for obtaining a nickel-iron-cobalt-enriched leachate and a copper-enriched leaching slag, which is a selective leaching unit and a water dissolution unit, or an atmospheric selective leaching unit, wherein the selective leaching unit has respective continuous feed inlets for a low-grade nickel matte and a leaching reaction solution, and the selective leaching unit contains a reaction base liquid, and allows a selective leaching reaction of a low-grade nickel matte obtained by matte smelting of copper-nickel sulfide ore and a leaching reaction solution when added continuously to the reaction base liquid; and the selective leaching unit further comprises a gaseous hydrogen sulfide collection device, a first leachate collection device, and a first leaching slag collection device, where the reaction base liquid is a 20-60 wt % sulfuric acid solution, and the leaching reaction solution is a 60-95 wt % sulfuric acid solution; the water dissolution unit is used to dissolve the first leaching slag in water, to collect a second leachate and a second leaching slag respectively; and the atmospheric selective leaching unit is used to subject a low-grade nickel matte directly to atmospheric selective leaching with sulfuric acid, to collect gaseous hydrogen sulfide, a leachate, and a leaching slag respectively; an iron removal unit, for removing iron from the second leachate obtained in the water dissolution unit, or for removing iron from the leachate obtained in the atmospheric selective leaching unit; a nickel and cobalt extraction unit, for collecting an iron removed liquid obtained in the iron removal unit and for extracting nickel and cobalt; an iron making unit, for treating an iron residue obtained in the iron removal unit and for iron making; and/or a copper smelting unit, for performing copper smelting on the second leaching slag or the leaching slag obtained in the atmospheric selective leaching unit, to obtain copper and noble metals, respectively.

10 . The system according to claim 9 , further comprising:
a sulfur production unit, for allowing the sulfur dioxide generated in matte smelting to react with the gaseous hydrogen sulfide generated in the atmospheric selective leaching unit to produce sulfur; a sulfuric acid production unit, for converting part of the sulfur dioxide generated in matte smelting into sulfuric acid and supplying the sulfuric acid to the atmospheric selective leaching unit; and a matte smelting unit, for treating copper-nickel sulfide ore, and supplying low-grade nickel matte to the atmospheric selective leaching unit, wherein the low-grade nickel matte is produced by matte smelting of the copper-nickel sulfide ore.

Assignees

• Univ Central South

Inventors

• Zhao Zhongwei
• Li Yongli
• Liu Xuheng
• Xiao Wanhai
• Chen Xingyu
• Li Jiangtao

Classifications

• C22B3/08 Primary

  Sulfuric acid {, other sulfurated acids or salts thereof} · CPC title

• C22B15/001

  with modification of the copper constituent · CPC title

• C22B23/005

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

• C22B23/0484

  in acidic type solutions · CPC title

• C22B15/0071

  containing sulfur · CPC title