HEAVY NON-FERROUS METALS | |
ArticleName | Modeling and optimization of parameters of sulfuric-acid leaching of zinc-containing middlings of two-stage Waelz processing of zinc cakes |
ArticleAuthor | Panshin A. M., Mamyachenkov S. V., Anisimova O. S., Kulenova N. A., Khodyko I. I. |
ArticleAuthorData | JSC “UMMC-Holding”, Verkhnyaya Pyshma: A. M. Panshin, Technical Officer
Ural Federal University named after the first President of Russia B. N. Yeltsin, Ekaterinburg, Russia: S. V. Mamyachenkov, Professor, e-mail: svmamyachenkov@yandex.ru O. S. Anisimova, Assistant Professor, Chair of Heavy Non-Ferrous Metals Metallurgy
D. Serikbayev East Kazakhstan State Technical University, Ust-Kamenogorsk, Republic of Kazakhstan: N. A. Kulenova, Professor, Head of Metallurgy Chair
JSC “Elektrozinc”, Vladikavkaz, Russia: I. I. Khodyko, Executive Officer |
Abstract | Definition of conditions of maximal zinc transfer in productive solution was carried out due to optimization and modeling of results of laboratory experiments for calcined Waelz-oxide leaching by sulfuric acid and reverse electrolyte. Using the computer program Statistica-7, the obtained data were processed in the form of models. Extraction rate of contaminants in the solution depends on the zinc:acid ratio. With stoichiometric ratio of 1:1, zinc and iron hydrocompounds, inhibiting contaminants' output, are formed on the surface of Waelzoxide particles. Dissolution of the film of reaction products, removing internal diffusion limitations, is observed with zinc:acid ratio of 1:1.2. Dependence of copper recovering on pH, duration and zinc:acid ratios in all series is characterized by initial induction period for the first 30 minutes of leaching. With a surface layer of iron cations (III), having oxidizing properties, equilibrium shifts towards copper cations Cu2+. According to this, significant amount of these cations appear in the solution. Reaching pH > 3 value, part of iron (Fe (III)) forms a basic salt solution and ferrous hydroxide, reducing its concentration. Formation of two fractions in cake after leaching was substantiated by various mechanisms of crystallization of calcium and lead sulfates. Micro-X-ray-spectral analysis has shown, that fine fraction contains mostly zinc and calcium sulfates, while coarse fractions contain residual zinc oxide and lead sulfate. Iron, copper and arsenic oxides were found in contaminants' form (within 1%) in both fine and coarse fractions. |
keywords | optimization, modeling, leaching, calcined Waelz-oxide, productive solution, fraction, cake, calcium sulfate, lead sulfate, micro-X-ray-spectral analysis |
References | 1. Panshin A. M., Anisimova O. S., Mamyachenkov S. V., Karelov S. V. Fazovyy sostav produktov veltsevaniya tsinksoderzhashchikh pyley chernoy metallurgii (Phase composition of products of Waelz processing of zinc-containing ferrous metallurgy dusts). Tsvetnye Metally = Non-ferrous metals. 2013. No. 8. pp. 51–55. |
Language of full-text | english |
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