Comprehensive utilization method of slag iron concentrates of wet-type zinc smelting furnace

Abstract

The invention relates to a comprehensive utilization method of slag iron ore concentrates of a wet-type zinc smelting furnace and belongs to the technical field of metallurgy. The method comprises the following steps: performing two-section counterflow leaching on raw material (slag iron ore concentrates in the wet-type zinc smelting furnace) in the presence of a hydrochloric acid aqueous solution serving as a leaching agent so that valuable metals such as iron, silver, copper, lead, zinc and arsenic in the slag iron ore concentrates enter a leachate; purifying the leachate by utilizing processes of metal iron powder replacement, control over pH (Power Of Hydrogen) value, arsenic sedimentation, sulfuration precipitation and the like, separating the valuable metals such as copper, silver, lead, zinc and arsenic, wherein the purified leachate is a pure FeCl2 aqueous solution; performing thermal decomposition on the pure FeCl2 aqueous solution in a spraying manner so as to obtain Fe2O3 powder; and absorbing the generated HCL gas with water so as to regenerate hydrochloric acid which returns to the leaching process. By the method, the valuable elements in the slag iron ore concentrates of the wet-type zinc smelting furnace are comprehensively separated and recycled; and the hydrochloric acid taken as a leaching agent can be recycled, so that the method realizes resource conservation and is friendly to the environment. During the whole process, the discharge of three wastes is basically avoided; all the resources are utilized to the greatest extent; and obtained products are convenient for subsequent treatment and processing. The method has the advantages of environmental friendliness, economical performance, energy conservation and high resource utilization rate, thereby being convenient for industrial production.

Description

technical field [0001] The invention relates to a method for comprehensive utilization of iron ore slag from a hydrometallurgy zinc kiln, belonging to the technical field of metallurgy. Background technique [0002] In 2011, the output of metal zinc in my country reached 4.46 million tons, of which about 85% were produced by wet method. Zinc hydrometallurgy includes conventional leaching, high temperature and high acid leaching, normal pressure and high pressure oxygen leaching and other processes, all of which have been applied in my country. The output of conventional leaching processes accounts for about 50% of my country's wet zinc production. In the conventional leaching process, the roasted ore is subjected to two-stage countercurrent leaching of neutral and low acid, in which Pb, Au, Ag, In, Ge, Ga, 60% Cu, 30% Cd and 15% Zn enter the leaching residue. The leaching residue is treated by Wiltz method, that is, after drying, it is mixed with 45-55% coke powder, mixed a...

AI Technical Summary

Problems solved by technology

Since only part of iron, copper and zinc enter the leaching solution in sulfuric acid leaching, most of silver, lead and part of copper and zinc remain in the leaching slag, and rare and precious metals and other valuable elements cannot be recovered.

Moreover, the market for polymerized ferric sulfate products is small, and this process has not achieved industrial production; the second method is to melt and cast iron concentrates from kiln slag into iron anodes, which are treated by electrolysis, and the cathodes produce pure iron products as powder metallurgy Raw material utilization, other valuable elements are recovered from electrolyte or anode slime respectively

This process technology is difficult, coupled with the restrictions on the sales of pure iron products, the economic benefits are difficult to guarantee, and it has not been applied in industry.

[0006] To sum up, the zinc hydrometallurgy kiln slag iron concentrate has a large output and high content of valuable elements, and is a metal resource with high value. Realize comprehensive recycling of resources

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