State of the Art and Prospect for Recycling of Waelz Slag from Electric Arc Furnace Dust Processing

Resumo

The processing of electric arc furnace dust by the Waelz process forms the iron-containing residue called Waelz slag. In the paper, best practices for recycling of Waelz slag from electric arc furnace dust processing have been analyzed and physicochemical characteristics and microstructure of the Waelz slag obtained from JSC Chelyabinsk zinc plant have been investigated. Chemical analysis of the Waelz slag composition has shown that it contains 26.4 wt % of iron with a metallization degree of 47 and 18.7 wt % carbon. It also contains about 1 wt % of zinc unevaporated during Waelz process. It has a complex multicomponent mineralogical composition. Analysis of papers has shown that currently Waelz slag recycles mainly in the construction industry in the production of cement, concrete, bricks and for road making. There is a limited number of papers devoted to recycling of Waelz slag in metallurgy because it contains too high values of contaminants such as zinc, lead, sulfur, phosphorus and copper. It is expedient to apply for recycling of Waelz slag the reduction smelting with obtaining of pig iron, slag suitable for construction industry and zinc-lead fume.