• Resources Recycling
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• v.23 no.1
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• pp.58-63
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• 2014

Variety of volatile materials is present in crude-Zinc oxide recovered from EAFD(Electric arc furnace steel dust). Commonly, it is purified by oxidizing roasting. In this study, spherical each specimen prepared crude-zinc oxide like 1~3 mm and 10 mm was tested in vertical tube furnace at the temperature range $600^{\circ}C$ to $1200^{\circ}C$ in oxidizing atmosphere. Oxidizing roasting properties of zinc oxide were investigated using XRD, XRF and ICP-OES. At temperature blow $950^{\circ}C$ volatilization rate were remarkably low. As the temperature increases, the concentration of Zn increased and the concentration and XRD peaks of impurities decreased. The result indicated that volatilization rate depended on specimen size and roasting temperature.

• Journal of Environmental Science International
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• v.25 no.2
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• pp.331-336
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• 2016

In this study the optimum conditions for recovery of valuable metal in Electric Arc Furnace Dusts were investigated. 2M of $H_2SO_4$, 1~5 of solid/liquid ratio, 0~180 min of leaching time has been established for leaching condition, and for electrowinning, each of Pt, C, Zn, Pb anode and Zn, Cu cathode was compared respectively at pH 2, 4 and 6. The result of elemental analysis of Zn crystal, a lagre quantity of Fe and H has been observed with Zn and other heavy metal, therefore, impurities removing process would be requir for enhancing purity of Zn. As the result, about 60% of Zn has been recovered under condition of 2 M of $H_2SO_4$, 1:2 of S/L ratio at 120 min, and Pt or Pb for anode, Zn for cathode has been shown the highest efficiency of electrowinning at pH 6.

• Resources Recycling
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• v.15 no.4 s.72
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• pp.44-51
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• 2006

Most electric arc furnace dust (EAFD) treatment processes to recover zinc from EAFD employ carbon as a reducing agent for the zinc oxide in the EAFD. In the present work, the reduction reaction of zinc oxide with carbon in the present of iron oxide was kinetically studied. The experiments were carried out at temperatures between 1173 K and 1373 K under nitrogen atmosphere using a weight-loss technique. From the experimental results, it was concluded that adding the proper amount of iron oxide to the reactant accelerates the reaction rate of zinc oxide with carbon. This is because iron oxide in the reduction reaction of zinc oxide with carbon promotes the carbon gasification reaction. The spherical shrinking core model for a surface chemical reaction control was found to be useful in describing kinetics of the reaction over the entire temperature range. The reaction has an activation energy of 53 kcal/mol (224 kJ/mol) for ZnO-C reaction system, an activation energy of 42 kcal/mol (175 kJ/mol) for $ZnO-Fe_{2}O_{3}-C$ reaction system, and an activation energy of 44 kcal/mol (184 kJ/mol) for ZnO-mill scale-C reaction system.