JSC “Chelyabinsk Zinc Plant”, Chelyabinsk, Russia:

P. A. Kozlov, Head of Engineering Center, e-mail: pak@zinc.ru
D. A. Ivakin, Head of Technological Bureau of Engineering Center
Yu. V. Reshetnikov, Deputy Technical Director — Head of Production Department

Recycling of anthropogenic zinc-containing materials in zinc plants solves the problems of extraction of non-ferrous metals into marketable products, and recycling of products, which cumulation makes a negative impact on environment. The process of pyrometallurgical processing technology uses the development of effective technical solutions based on physical properties of materials and their chemical composition. Such solution is to prepare the charge of Waelz-process including wet lime slag of waste water treatment as a binder for pulverized raw material and calcium-containing flux. The studies were carried out in enlarged laboratory setup for performing of Waelz-process of man-made oxidized zinccontaining materials - electric arc furnace dust and lime sludge of waste water treatment of zinc enterprise. Distribution of sulfur as a component, partially removed from the charge into off-gases of Waelz kiln was defined. The co-processing of products (in the ratio of dry materials 4:1) enables to carry out the following measures:
– using the wet sludge as a binder for granulation of fine EAF dusts (obtained pellets are approximately two times stronger than ones, pelletized using water);
– reduction of emissions of sulfur in the form of SO₂ with offgases of Waelz kiln from coke breeze by three times;
– reduction of SO₂ concentration in off-gases of Waelz kiln (compared to independent sludge processing) from 1360 to 200 mg/m³;
– increasing of sulfur recovery from sludge into Waelz kiln clinker.
Increase in output of sulfur with clinker makes a positive impact on further processing of obtained Waelz oxide: emissions of SO₂ with gases of calcining furnaces are reduced together with input of sulphate sulfur in zinc cycle solutions.

1. Panshin A. M., Leontev L. I., Kozlov P. A., Dyubanov V. G., Zatonskiy A. V., Ivakin D. A. Tekhnologiya pererabotki pyli elektrodugovykh pechey Otkrytogo Aktsionernogo Obshchestva “Severstal” v velts-komplekse Otkrytogo Aktsionernogo Obshchestva “Chelyabinskiy Tsinkovyy Zavod” (Technology of processing of JSC “Severstal” electricarc furnaces' dust in Waelz-complex of JSC “Chelyabinsk Zinc Plant”). Ekologiya i promyshlennost Rossii = Ecology and industry of Russia. 2012. No. 11.
2. Kozlov P. A. Velts-protsess (Waelz-process). Moscow : “Ore and Metals” Publishing House, 2002.
3. Peysakhov I. L., Karmazina V. D. Pyleulavlivanie i ochistka gazov v tsvetnoy metallurgii (Dust collecting and gas purification in non-ferrous metallurgy). Moscow : Metallurgizdat, 1959. pp. 164–211.