Assessment of electric arc furnace dust: Powder characterization and its sinterability as ceramic product

Industrial wastes' disposal and their utilization for production of important sintered ceramic materials is one of the hot topics. Electric arc furnace dust (EAF) is a hazardous waste generated during steelmaking process in electric arc furnace. Its main components are Fe and Zn oxides which are important for many applications. In the present work, the assessment of EAF dust and its possibility for production of sintered ceramic bodies were studied. The assessment included chemical, physical and magnetic properties. The chemical and phase compositions were investigated by X-ray fluorescence (XRF), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Scanning electron microscope (TEM) attached with EDAX unit and transmission electron microscope (TEM) were used to investigate the morphology and particle size of the dust. The thermal stability of the dust was studied by its heat treatment up to 1000 degrees C. The magnetic property was also tested for uncalcined and calcined dust by vibrating sample magnetometer (VSM). Moreover, the sinterability of the dust was conducted'at different firing temperatures up to 1250 degrees C. The sintered specimens were investigated through their bulk density, apparent porosity, microstructure and compressive strength. The results revealed that the dust composed mainly of major oxides such as FexOy, and ZnO, in addition to some minor oxides. So the detected phases were ZnFe2O4 and ZnO as main constituents of EAF. The particle size of powder as exhibited by SEM and TEM was between 20 nm and 2 mu m. After calcination at 1000 degrees C, the main phases were found to be stable with the disappearance of some trace phases like NaCl. Also, it is found that the magnetization was decreased after calcination. Moreover, sintered ceramic bodies having good physical and mechanical properties were successfully obtained after sintering up to 1250 degrees C, and can be used for different applications.