A modified additive for recovering copper and iron from copper smelting electric furnace depleted slag and its application

Abstract

The invention relates to a modified additive for recycling copper and iron in depleted slag of an electric copper smelting furnace and an application thereof. The modified additive comprises, by mass, 40-50% of quick lime, 10-15% of manganese monoxide, 10-15% of pyrite, 5-15% of copper pyrite and 10-20% of iron oxides. According to the application of the modified additive for recycling copper and iron in depleted slag of the electric copper smelting furnace, the amount of the added modified additive is 8-20% of the mass of the copper slag. By means of the modified additive, mineral phase reconstruction of iron and copper target minerals is realized by making full use of high-temperature latent heat of depleted slag of the electric copper smelting furnace. The modified additive has the functions of fayalite modification, induced crystallization of initial crystal seeds and stabilization of copper matte minerals. Copper concentrates for copper smelting and magnetite concentrates for iron smelting can be produced by using modified slag through a floatation-magnetic separation process. Accordingly, efficient separation and recycling of iron and copper in depleted slag of the electric copper smelting furnace are realized, resources are saved, and energy consumption is reduced.

Description

technical field [0001] The invention relates to a high-temperature modification additive for comprehensively recovering copper and iron from depleted slag of a copper smelting electric furnace and its application, and belongs to the technical field of resource utilization of metallurgy and industrial waste residue. Background technique [0002] About 80% of the world's copper is produced by pyrometallurgy, and the remaining 20% ​​is obtained by hydrometallurgy. Usually, 1 ton of matte can produce 2-3 tons of copper slag. More than 97% of copper in my country is obtained by pyrometallurgy, such as reverberatory furnace smelting, flash furnace smelting, electric furnace smelting and converter smelting. In 2015, the output of refined copper in my country was as high as 7.96 million tons. At the same time, more than 15 million tons of copper slag were produced every year, and the cumulative output exceeded 120 million tons. [0003] Copper slag contains a large amount of availa...

AI Technical Summary

Problems solved by technology

The minerals in the copper slag are embedded with each other and the crystal grains are small. It is very difficult to recover copper and iron in the slag by using traditional separation techniques, such as flotation, gravity separation and magnetic separation, and the recovery rate of iron is only about 30%. The copper recovery rate of chemical slag is only 65-75%

In addition, the depleted slag of the copper smelting electric furnace is in a high-temperature molten state. At present, only slow cooling or rapid cooling is used, and a large amount of latent heat has not been utilized.

[0004] At home and abroad, a lot of research has been done on the recovery of copper and iron from copper slag, but there are few reports on the high-temperature modification by using the latent heat of the copper slag when it is depleted in an electric furnace.