Helmut-Schmidt University (Hamburg, Germany):

Andersson M., Mag. Eng., Scientifi c Fellow, Automation Institute, matthias.andersson@hsu-hh.de
Haverkamp V., Dr. Eng., Inv. Prof., Automation Institute

Max Aicher Unternehmensgruppe (Freilassing, Germany):
Krüger K., Dr. Eng., Prof., honor. Prof., Automation Institute, at p.t. Advisor

ArcelorMittal Hamburg GmbH (Hamburg, Germany):
Jüchter A., Mag. Eng., Head of Steel Mlting Shop & Reduction Unit
Braun U., Dr. Eng., Head of Dept.

It is shown that the main aim in steel production in an electric arc furnace is achieve the required melt weight and temperature. However, it is impossible to provide continuous temperature management via its measuring, because the temperature measurements are discrete. After previously charged solid scrap has mol-ten down, direct reduced iron (DRI) is continuously charged in the electric arc furnace of ArcelorMittal Hamburg GmbH and thereby typically replaces up to 75% of scrap. Throughout DRI-feeding, arcs should be covered by foaming slag for stable operation and high energy efficiency. This requires a defined, constant steel bath temperature as well as an overheating process targeted at a predefi ned tapping weight and temperature. Both can be realized with a new temperature-based DRI-feeding-control using a temperature prediction model that has been developed in this joint research. It has 18 K standard temperature error and allows to provide adjustment of DRI feeding intensity depending on melt temperature in order to reach the requirement temperature range. The fi nal results are rather promising, they confi rm possibility to apply automatic process for a hot phase. This model is integrated in the metallurgical plant control system and helps to improve additionally the melting process.

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