Method for extracting zinc from multi-element difficult-to-treat metallurgical waste residues

Abstract

The invention provides a method for extracting zinc from multi-element difficult-to-treat metallurgical waste residues, comprising the following steps of: mixing a waste solution and a new solution into an electrolytic circulating solution by taking a zinc sulphate water solution which reaches the Cl-ion content of 1800-3000 mg / L and is generated by pickling zinc oxide fumes obtained by treating the multi-element difficult-to-treat metallurgical waste residues containing the zinc as the new solution and according to the volume ratio of waste solution to new solution=8-10:1; controlling the zinc content of the electrolytic circulating solution to be 50-55 g / L, H<+> content to be 125-136 g / L, Mn<2+> content to be 5-20 g / L, Co<2+> content to be 2.5-3 mg / L, where the mass ratio of H<+>:Zn is equal to 2.5-3.8:1; respectively adding SrCO3 and bovine colloid to the electrolytic circulating solution according to the Zn content of 5-10 kg / t and 0.1-5.0 kg / t; and carrying out electrolytic deposition to obtain high-quality zinc under the process conditions of area current Dk=700-1000 A / m<2>, tank temperature ranging from 35 DEG C to 45 DEG C and a precipitation period of 12-18 hours. By adopting the invention, the harm of Cl-ions on a zinc electrode is furthest suppressed, the harm of Pb2+ ions inside the electrolytic circulating solution and PbO2 and PbSO4 particles on high-quality zincproduction is reduced, the output rate of the zinc reaches 100 percent.

Description

technical field [0001] The invention relates to a method for extracting zinc, in particular to a method for extracting high-quality zinc from zinc-containing multi-element refractory metallurgical waste residue, which belongs to the technical field of hydrometallurgy. Background technique [0002] In conventional electric zinc industrial production, zinc oxide dust with chemical composition: Zn 53-66%, Fe0.5-3.0%, Cl 0.03-0.4%, As 0.01-0.6% is usually selected as the raw material for electric zinc production. The zinc oxide dust mentioned above is obtained by collecting zinc-containing multi-element refractory metallurgical waste slag after fire reduction, volatilization and oxidation, in which the main metal grade is low, chloride ions and other impurities are high, especially when zinc sulfate aqueous solution Medium Cl - When the ion content is more than 1000mg / L, the cathode and anode plates used in the electrowinning process will be destroyed, not only the production o...

AI Technical Summary

Problems solved by technology

Although the removal rate of fluorine and chlorine by the fire method is high, the investment in process equipment is relatively large, and a certain scale must be formed. The roasting process has a large zinc loss, and the harmful gas produced will cause environmental pollution.