The presented article focuses on the possibilities of using microwave energy in the treatment of flue dust originating from the production of steel in EAF, as well as flue dust arising in the hot-dip galvanizing process of steel. The mentioned types of waste in the form of flue dust contain significant amounts of zinc (22-43%) and iron (0.6-30%), which could be reused after heat treatment in the sense of a circular economy. Since zinc is also found in the mentioned wastes in the form of a stable spinel structure of franklinite (ZnFe2O4), its treatment through microwave roasting in the presence of suitable susceptors of electromagnetic radiation is a prospective method of obtaining pure metals. The advantage of microwave processing is the volumetric nature of the heating, the faster course of carbothermic reactions and the sufficiently lower temperature of the waste treatment compared to conventional heating.