A process for comprehensive recovery of copper and iron by phase reconstruction of molten slag from copper smelting

Abstract

The invention relates to a process for comprehensively recycling copper and iron through ore phase restructuring of copper smelting molten slag. The process comprises the following steps of 1, molten slag ore phase restructuring, wherein when the copper smelting slag is in the molten state, a composite additive accounting for 8-20% of the mass of the copper slag is added, then gradual cooling treatment is conducted, and the composite additive is composed of 40-50% of quick lime, 10-15% of manganous oxide, 10-15% of pyrite, 5-15% of chalcopyrite and 10-20% of an iron oxide; 2, flotation, wherein after modified slag obtained in step 1 is subjected to crushing and ore grinding, floatation treatment is conducted; and 3, magnetic separation, wherein tailings obtained through flotation conducted in step 2 are subjected to wet type magnetic separation, so that iron ore concentrate and magnetic separation tailings are obtained. According to the process for comprehensively recycling the copper and the iron, starting from the high-temperature molten slag generate in the copper smelting process, smelting slag ore phase restructuring is conducted by fully utilizing heat of the molten slag; the iron and the copper are each made to form ore easy to separate, and grains of the ore are pushed to grow; and efficient iron recycling is achieved while the copper is recycled successfully.

Description

technical field [0001] The invention relates to a process for comprehensively recovering copper and iron by reconstructing ore phase reconstruction of molten slag from copper smelting, and belongs to the technical field of resource utilization of 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 about 2.2 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. The accumulated copper slag not only occupies a large amount of land and wastes resources, b...

AI Technical Summary

Problems solved by technology

In my country, the slag barrel method is mainly used. This process is simple and the investment is small, but it has poor adaptability to the copper smelting slag produced by different smelting furnaces. The crystallization size of copper minerals is small and uneven, the flotation index fluctuates greatly, and the production process is difficult to control. , especially iron cannot be efficiently recycled

On the other hand, if only the recovery of iron is considered, since most of the copper is easy to enter the iron phase, the copper in the obtained iron concentrate will exceed the standard, which will seriously affect the normal progress of the subsequent ironmaking process, so the recovery of iron must also recover copper

On the whole, the copper utilization rate of copper smelting slag in my country does not exceed 12%, while the iron utilization rate is less than 1%.

[0005] The technical bottlenecks of low recovery rate of copper and difficult utilization of iron in copper smelting slag are: low crystallization degree of minerals such as copper and iron in slag, fine crystal grains and wide range of particle size distribution, complex intercalation relationship between minerals, especially iron mainly composed of Fayalite exists in the form of fayalite, which is difficult to sort; and a large amount of latent heat is not fully utilized when the slag is discharged from the furnace

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