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Accumulation of the metallurgical waste stimulates development of the recycling technologies. The paper investigates the chemical and phase composition of the particular electric arc furnace (EAF) dust which is formed in the gas cleaning system during steel smelting from scrap. It was found that the main components of the EAF dust under study are ZnFe2O4, ZnO, CaCO3, SiO2 and KCl. The XRD phase analysis showed that the prevailing phase is zinc ferrite ZnFe2O4 (62 %). The thermodynamic analysis was carried out using TERRA software. According to modeling, the iron reduction proceeds sequentially ZnFe2O4 – Fe3O4 −FeO–Fe in the temperature range from 500 to 700 °C. Above 510 °C ZnFe2O4 decomposes with formation of ZnO and Fe3O4. Zinc oxide is intensively reduced in the temperature range from 800 to 900 °C passing into the gas phase. [ABSTRACT FROM AUTHOR]

In this paper, we simulated and investigated microwave heating of biochar containing electric arc furnace dust spherical pellet. The influence of the distribution of components within pellet on the effectiveness of microwave heating was investigated as well as the influence of biochar conductivity. We considered the interaction of pellet with both plane wave in free space and with H10 mode wave in a single-mode waveguide. In addition, effective permittivity and permeability of EAF dust in one of the possible compositions, and of biochar – EAF dust powders mixture depending on the volume fraction of EAF dust were calculated according to effective medium approach. [ABSTRACT FROM AUTHOR]

The production of cement leads to high carbon dioxide (CO2) emission which has a negative environmental impact. So, one of the ways to minimize this issue is by the proper use of supplementary cementitious materials also known as SCMs in cement production. This review paper aims to discuss the utilization and effects of SCMs in various binding mixtures of mortar including some advantages and limitations. SCMs are used as a partial substitute for cement. This paper emphasizes the reviewed results on the effect of the SCMs like silica fume, copper slag, steel slag, fly ash, electric arc furnace dust (EAFD), ground granulated blast-furnace slag (GGBS), limestone powder, etc on properties of cement mortar and paste. The results on properties of the mortar like flowability, strength (compressive, flexural and split tensile strength) and durability are presented. Besides, parameters like mortar performance, setting time, binding strength, etc are summarized. The effects of physical and chemical properties, fineness, pozzolanic activity, etc of SCMs on properties of mortar are also discussed. Mortars in which cement is replaced by the above-mentioned SCMs comparatively showed higher compressive and flexural strength depending on the replacement ratio and the curing age. Using GGBS as an SCM has enhanced the mortar performance with elevated temperature. Even mechanical and durability properties of the mortars are found to improve for copper slag and steel slag. Thus, the available tests and their findings from different studies have been reviewed, interpreted, and summarized. [ABSTRACT FROM AUTHOR]

The paper considers the asymmetrical current and voltage of a single operating arc furnace, powered by a 220/35kV power transformer, included in the metallurgical enterprise system. The uneven current load of the individual phases was examined and the dynamics of the asymmetry coefficient was evaluated. The results from the studies can be used as basic prerequisites in the selection and setting of relay protection of such consumers. [ABSTRACT FROM AUTHOR]