from the conferences organized by TANGER Ltd.
Fluorspar is the commercial name, currently used in metallurgy. Usually it refers to crude or beneficiated material that is mined and (or) milled from the mineral fluorite (calcium fluoride, CaF2). From the point of view of ecology and working conditions, the use of fluorite as a slag-forming material causes very harmful fluorine emissions into the atmosphere. From the point of view of technology, it helps to reduce the viscosity of slag by liquefying it on one hand side, however increases the aggressive effect of slag on the refractory lining and shortens its durability on other hand side. We should remember, that the circular economy model (CE) relies on the fact that materials used in production circulate rather than become waste. That’s why, the authors of this article want to develop a new generation of materials - synthetic slag based on by-products from the production of ferroalloys. For this purpose, post-production slag, rich in Al2O3 and CaO, and some modifiers were used to correct the chemical and mineralogical composition, as well as to reduce the melting point of the developed refining mixtures. The chemical and thermodynamic aspects, were another advantage of developing such slags, because in the case of slag liquefaction via used calcium aluminates, the refining slag remains liquid for a long time, not only for a limited period of time, as is the case with CaF2 liquefaction. The use of two newly developed slags during secondary metallurgy treatment in steelmaking processes will allow to eliminate the use of fluorite (CaF2), which has many drawbacks. One of them is the negative effect arising outside the steel production, namely in the process of recovery of zinc from steel dust in the electrolytic process. The presence of fluorine in zinc-rich dusts collected on filters makes zinc recovery difficult. The elimination of fluorite will also reduce the fluoride content of steel dusts destined for zinc recovery.
Keywords: Recycling, circular economy, elimination of fluoride, refining slag© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.