CN-121992209-A - Method for strengthening collection and recovery of valuable metals in olivine-type iron-rich nonferrous metal smelting slag

Abstract

The invention discloses a method for collecting and recycling valuable metals in olivine-type iron-rich nonferrous metal smelting slag, which comprises the steps of proportioning the olivine-type iron-rich nonferrous metal smelting slag, strontium carbonate, manganese carbonate and calcium carbonate additives, carrying out oxygen-enriched roasting, and carrying out cooling, ore grinding and magnetic separation on the obtained roasting product to obtain a valuable metal enriched product, wherein the valuable metal enriched product can be used as an important raw material of nonferrous metal metallurgy. The method is particularly suitable for enriching and separating valuable metals of nickel, cobalt, copper and zinc which are wrapped in complex olivine type nonferrous metal smelting slag.

Inventors

• LIU BINGBING
• HAN GUIHONG
• HUANG YANFANG
• SUN HU
• SU SHENGPENG
• YANG SHUZHEN
• PENG LONG

Assignees

• 郑州大学

Dates

Publication Date

20260508

Application Date

20260106

Claims (8)

1. 1. A method for capturing and recycling valuable metals in olivine-type iron-rich nonferrous metal smelting slag is characterized in that the olivine-type iron-rich nonferrous metal smelting slag, strontium carbonate, manganese carbonate and calcium carbonate additives are subjected to proportioning and oxygen-enriched roasting, and the obtained roasting product is subjected to cooling, ore grinding and magnetic separation procedures to obtain the valuable metal enrichment product, wherein the proportioning of the olivine-type iron-rich nonferrous metal smelting slag, the strontium carbonate, the manganese carbonate and the calcium carbonate meets the condition that the mass ratio of valuable metal+strontium+manganese element to iron element is (0.10-0.35): 1, the mass ratio of strontium to manganese element is (0.05-0.35): 1, the mass ratio of CaO to SiO 2 is (0.2-1.0): 1, and the mass range of iron in the smelting slag is 15% -55%, and the valuable metals are one or more of copper, zinc, cobalt and nickel.
2. 2. The method for capturing and recycling valuable metals in reinforced olivine-type iron-rich nonferrous metal smelting slag according to claim 1, wherein the olivine-type iron-rich nonferrous metal smelting slag is one or more of copper slag, nickel slag and cobalt slag.
3. 3. The method for capturing and recycling valuable metals in reinforced olivine-type iron-rich nonferrous metal smelting slag according to claim 1, wherein the content of SrCO 3 、MnCO 3 、CaCO 3 in the strontium carbonate, manganese carbonate and calcium carbonate additive is not less than 85wt%.
4. 4. The method for capturing and recycling valuable metals in reinforced olivine-type iron-rich nonferrous metal smelting slag according to claim 1, wherein the mixture obtained after the proportioning has a particle size of 200 meshes and a mass ratio of fine fraction of 100%.
5. 5. The method for capturing and recycling valuable metals in the reinforced olivine-type iron-rich nonferrous metal smelting slag according to claim 1, wherein the roasting is performed at 1150-1200 ℃ for 10-30 min, then the temperature is raised to 1250-1280 ℃ for 10-25 min, and the oxygen volume content in the roasting atmosphere is not less than 25% during the roasting.
6. 6. The method for capturing and recycling valuable metals in reinforced olivine type iron-rich nonferrous metal smelting slag according to claim 1, wherein the cooling mode is air cooling or furnace-following cooling.
7. 7. The method for capturing and recycling valuable metals in reinforced olivine type iron-rich nonferrous metal smelting slag according to claim 1, wherein the grinding is 100% of fine fraction of the grinding to 200 meshes, and 15% -25% of fine fraction of 300 meshes.
8. 8. The method for capturing and recycling valuable metals in reinforced olivine type iron-rich nonferrous metal smelting slag of claim 1, wherein the magnetic field strength in the magnetic separation process is 200-650 gauss.

Description

Method for strengthening collection and recovery of valuable metals in olivine-type iron-rich nonferrous metal smelting slag Technical Field The invention belongs to the field of smelting slag dressing and smelting combined separation and quality improvement, and particularly relates to a method for capturing and recycling valuable metals in reinforced olivine type iron-rich nonferrous metal smelting slag. Background ‌ The research on the large-scale digestion and utilization technology of the copper slag/nickel slag metallurgical solid waste meets the national important strategic requirements of green transformation development and comprehensive improvement of the solid waste resource utilization rate of the resource industry in China. Copper slag is an iron-rich solid waste generated in the process of pyrometallurgy copper, and has a complex phase composition. The copper slag discharge amount of China exceeds 2000 ten thousand tons per year. China is a country with large nickel slag production amount. At present, the comprehensive utilization rate of nickel slag is only about 10%, most of nickel slag is piled up and disposed, and the environmental protection risk is always an industry 'heart disease'. The national economic and social development planning clearly provides the aim of obviously improving the comprehensive utilization rate of the newly increased solid wastes and orderly reducing the solid wastes in large quantities. Therefore, the research significance of developing large-scale digestion and utilization technology of copper slag/nickel slag is great. Matte smelting of copper, nickel and cobalt sulphide concentrate belongs to oxidation smelting. The affinity of copper, nickel and cobalt to sulfur is similar to iron, while the affinity to oxygen is far smaller than the physicochemical property of iron, so that the sulfide of iron is continuously oxidized into oxide in the smelting process of matte with different oxidation degrees, and then slag is formed with gangue to remove the sulfide. In the process of smelting matte by sulphide ore, the behavior of iron is one of the core metallurgical processes, mainly involving the generation and conversion of iron sulfides and oxides and the distribution between matte (matte/nickel) and slag, directly affecting metal recovery and process efficiency. ‌ iron is mainly present in the form of FeS (ferrous sulfide) in matte smelting, and iron sulfide in the raw material (e.g. FeS 2) is decomposed or oxidized at high temperature. FeS is oxidized into FeO preferentially, and when the oxygen level is higher, feO is further oxidized to generate Fe 3O4 (ferroferric oxide) to perform oxidation reaction, so that a large amount of heat is released, and the high temperature required by smelting is maintained. ‌ iron oxide reacts with the added flux (e.g., siO 2) to form slag. FeO combines with SiO 2 to form fayalite (2FeO.SiO 2), which constitutes the main component of the iron silicate slag. The slag composition is typically 30% -40% SiO 2, 38% -50% FeO and 8% -10% CaO, wherein the SiO 2 content needs to be nearly saturated (35% -40%) to reduce the slag viscosity and promote separation of matte from slag. Due to the characteristics and efficiency of the smelting process, the nickel slag contains 30% -40% of iron and contains trace amounts of nickel, cobalt, copper and other nonferrous metals, the main iron-containing phase is a fayalite phase, and the nickel slag is wrapped by a glass phase, so that the nickel slag has a compact structure, high comprehensive utilization difficulty and low utilization rate. The copper slag mainly comprises iron and oxides thereof, copper, silicon dioxide, aluminum oxide, calcium oxide and the like, and also contains associated elements such as zinc, lead, cobalt, nickel and the like and a small amount of noble metals such as gold, silver and the like. Copper exists mainly in sulfide, oxide and metal states, and iron exists mainly in silicate (e.g., fayalite Fe 2SiO4) and magnetite (Fe 3O4) forms. The scholars at home and abroad develop a great deal of effective research on the comprehensive utilization technology of copper slag/nickel slag solid waste, and the nickel slag recycling is mainly concentrated on the separation and recovery of valuable metals and mainly comprises the processes of physical mineral separation, direct reduction, melt oxidation-grinding separation, wet digestion and the like. The high-temperature reduction/oxidation-grinding technology based on regulating and controlling the magnetic property of the iron mineral phase can efficiently realize the separation and enrichment of iron, and the iron recovery rate can reach more than 80%. However, in the high-temperature reduction process of copper slag/nickel slag, a calcareous flux is required to be added to destroy the olivine structure, and a large amount of secondary smelting slag is required to be further treated. In addition, the magnet mineral phase and