Institute of Metallurgy of Ural Branch of Russian Academy of Sciences, Ekaterinburg, Russia:

S. N. Tyushnyakov, Post-Graduate Student
E. N. Selivanov, Director, e-mail: pcmlab@mail.ru
V. M. Chumarev, Chief Researcher

Estimation of rate of zinc distillation from slag of autogenous melting of copper-zinc concentrates in direct-current arc furnace was carried out, using the following initial mate rials:
— slag of autogenous melting of copper concentrate, containing 1.0% of Cu, 6.4% of Zn, 39.5% of Fe_total, 3.7% of CaO, 30.8% of SiO₂ and 2.4% of S;
— blast furnace production slime, containing 0.5% of Zn, 41.1% of Fe_total, 6.8% of CaO, 5.7% of SiO₂, 2.6% of Al₂O₃ and 21.0% of C.
The slags' structure after remelting in induction and directcurrent arc furnaces was studied by methods of X-ray phase and X-ray spectrum microanalysis. Zinc in the phase components of slag was revealed in ferrite, silicate and sulfide compounds. Remelting (1270–1300 ^оC) of slag in induction furnace leads to the partial distillation of zinc without a significant change of slag composition. Melting of zinc-containing slag in direct-current arc furnace significantly reduces a residual content of zinc and copper in slag, while the rate of zinc distillation from slag is 0.1–2.9 mg/(cm^₂·s). The essential reduction of the zinc content both in iron-silicate phases (by 3–5 times) and sulfide phases (up to less than 0.1%) was observed in the slags, crystallized after zinc distillation. Zinc-containing sublimates (~60% Zn) and Fe-based metallic phase, containing 0.5–1.0% of С and 4–6% of Cu, are formed during the reduction melting of slag together with blast furnace production slime in direct-current arc furnace. Zinc and copper contents in depleted slag are reduced to percent fractions. According to their zinc content, the sublimates, collected during the experiments, can be suitable for subsequent hydrometallurgical processing on zinc plants. There is shown the prospect of usage of electric direct-current arc furnaces for processing of zinc-containing slags, together with other wastes.

1. Vanyukov A. V., Bystrov V. P., Vaskevich A. D. et al. Plavka v zhidkoy vanne (Melting in liquid bath). Moscow : Metallurgiya, 1988. 208 p.
2. Khalemskiy A. M., Tarasov A. V., Kazantsev A. N. et al. Plavka v pechi Vanyukova medno-tsinkovogo sulfidnogo syrya (Melting of copper-zinc sulphide raw materials in Vanukov furnace). Ekaterinburg : Kedr, 1993. 80 p.
3. Paretskiy V. M., Nus G. S., Panfilov S. A. et al. Tsvetnye Metally — Non-ferrous metals. 1996. No. 4. pp. 47–50.
4. Nus G. S. Rudno-termicheskie shlakovye elektropechi (Orethermal slag electric furnaces). Moscow : Energoatomizdat, 2004. 199 p.
5. Bagrova T. A., Tarasov A. V., Meyerovich E. V. et al. Tsvetnye Metally — Non-ferrous metals. 1986. No. 12. pp. 23–26.
6. Komkov A. A., Bystrov V. P., Rogachev M. B. Tsvetnye Metally — Non-ferrous metals. 2006. No. 5. pp. 17–24.
7. Okunev A. I., Kostyanovskiy I. A., Donchenko P. A. Fyumingovanie shlakov (Fuming of slags). Moscow : Metallurgiya, 1966. 259 p.
8. Kozyrev V. V. Tsvetnye Metally — Non-ferrous metals. 2009. No. 2. pp. 61–64.
9. Sannikov Yu. I., Lyamina M. A., Kesler M. Ya. et al. Izvestiya Akademii nauk SSSR. Metally — Proceedings of USSR Academy of Sciences. Metals. 1988. No. 5. pp. 5–11.
10. Chumarev V. M., Okunev A. I. Doklady Akademii nauk SSSR — Reports of USSR Academy of Sciences. 1966. Vol. 170, No. 5. pp. 1143–1146.
11. Leontev V. G., Bryukvin V. A. Metally — Metals. 1995. No. 1. pp. 14–20.
12. Selivanov E. N., Gulyaeva R. I., Zelyutin D. I. et al. Tsvetnye Metally — Non-ferrous metals. 2009. No. 12. pp. 27–31.
13. Efimova A. I., Belorukova L. P., Vasilkova I. V. et al. Svoystva neorganicheskikh soedineniy (Properties of inorganic compounds). Leningrad : Khimiya, 1983. 392 p.
14. Chumarev V. M., Selivanov E. N., Kharitidi G. P. et al. Tsvetnye Metally — Non-ferrous metals. 2010. No. 7. pp. 25–28.
15. Lakernik M. M. Elektrotermiya v metallurgii medi, svintsa i tsinka (Electrochemistry in metallurgy of copper, lead and zinc). Moscow : Metallurgiya, 1964. 284 p.
16. Seregin P. S., Popov V. A., Tsemekhman L. Sh. Tsvetnye Metally — Non-ferrous metals. 2010. No. 10. pp. 27–33.