V. Yu. Risonarta, Siemens VAI Metals Technologies GmbH, Germany; M. Kirschen, RHI AG Process Technology and Systems Solutions, Austria; H. P. Yung; S. Lenz; Ch. Beiler, Deutsche Edelstahlwerke GmbH, Germany; Th. Echterhof; H. Pfeifer., Chair of Industrial Furnaces and Heat Engineering, Rheinisch-Westfälische Technische Hochschule Aachen, Germany; victor.y.risonarta@googlemail.com

In this research study, the empirical model of chromium concentrations of tapped steel from EAF was successfully developed. During stainless steelmaking in an electric arc furnace (EAF), chromium concentrations at tapping should be well pre-estimated for several reasons. The model shows good agreement with observed compositions intapped steel and many expected results. In addition to the high price of raw materials for stainless steelmaking, efficient inputs and minimum losses of raw materials are also necessary for sustainable steel production which result in optimum cost of raw materials and electrical energy. Both excessively low and high chromium concentrations require re-balancing procedures with ferro-alloys which decrease liquid steel temperature and EAF energy efficiency. An innovative strategy is outlined in this paper to obtain higher energy and raw materials efficiency, higher productivity and lower production cost. The empirical model outlined in this paper can be used for a future industrial application at Level-2 and Level-3 of steel plants. In general, not particularly at DEW Siegen, an increase in slag additive input by 10 kg/t or an increase in alloy input by 1 % mass content after the refining period decreases liquid steel temperature by morethan 20 °C, which corresponds to a decrease of steel enthalpy of more than 6 kWh/t. In the end, through optimisation of raw materials and energy input during steelmaking, European steel industries also show their significant contribution to decreasedirect and indirect CO₂ emissions.

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