Demag Aktiengesellschaft

Haye Roth

Gero Rath

Horst Konig

H W Gudenau

A method is provided for producing steel with a very low carbon content of as low as 0.015% by continuously maintaining a foaming slag layer at a particular volume, and using as the charge a pre-reduced sponge with a specified carbon/oxygen ratio. The process includes utilizing a slag with a specific content of iron and magnesium oxide.

Continuous smelting method

A process and apparatus are provided for producing steel of more uniform grade on a continuous basis by maintaining a comparatively thick slag layer and a larger quantity of molten steel product in an electric arc resistance furnace. This is achieved partially by including in or combined with a quantity of the charge a quantity of iron sponge, or by using a pre-reduced and/or agglomerated or otherwise pelleted ore charge. By using a charge which is comprised of comparatively small-sized particles in combination with a thick slag layer, the charge is readily assimilated into the thick slag layer. This reduces the exposure of large particle size charge material surfaces to hot spots caused by arcing at the charge-slag interface. The comparatively thick slag layer and the continuously maintained large metal bath balance and assimilate additional charge quantities to produce an ultimately more uniform product. Because of the thick slag layer, the upper surface thereof can be maintained comparatively cooler for receiving the charge, thus again reducing localized hot spots at the slag-charge interface. These factors reduce deterioration of the furnace lining and inlet feed surfaces, as well as enhancethe efficiency with which the applied electrical energy is used.

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Breitscheid, Germany

Haye Roth