Electric arc furnace arrangement for producing steel
AssigneeVoest-Alpine Industrieanlagenbeau GmbH
InventorsHarald Berger, Peter Mittag, Johannes Steins, Gert Pfeiffer
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Abstract
There is disclosed an electric arc furnace for the production of steel by melting scrap, in particular iron scrap, and/or sponge iron and/or pig iron as well as fluxes in a furnace vessel, into which at least one graphite electrode projects, which is displaceable in its longitudinal direction, wherein an electric arc is ignited between the graphite electrode and the charging stock. To achieve a particularly high energy input, the graphite electrode projects into a lower part of the furnace vessel from aside and the lower part, in the region of the graphite electrode, has an enlargement radially protruding outwardly relative to the upper part.
Claims28
In an electric arc furnace arrangement comprising a furnace vessel having an upper part, a lower part and a bottom associated with said lower part for receiving a metal charge to be melted, said metal charge to be received comprising at least one ferrous metal selected from the group consisting of iron scrap, sponge iron and pig iron, wherein said furnace vessel has at least one graphite electrode projecting therein capable of displacement along its longitudinal axis and of forming an electric arc by ignition with said metal charge, the improvement:
- wherein a region of said lower part of the furnace vessel is outwardly radially enlarged relative to its upper part to form a radially enlarged part,
- wherein said at least one graphite electrode projects laterally from outside of said vessel into the vessel in a region of entry into the radially enlarged part of said vessel and is arranged at a level with respect to the vertical axis of said furnace vessel, and
- wherein a plurality of oxygen burner lances are symmetrically radially arranged with respect to said vertical axis and horizontally disposed adjacent to said at least one graphite electrode on at least one level located above a level on which said graphite electrode is arranged for introducing fossil energy, said at least one graphite electrode being directed to a region in said lower part of the vessel adapted to receive and confine said metal charge for the melting thereof.
A process for producing steel from at least one ferrous metal selected from the group consisting of scrap, sponge iron and pig iron by using an electric arc shaft furnace arrangement comprising an upper shaft part and a lower melting vessel connected thereto,
- said shaft part at its upper end being provided with at least one closeable lateral charging opening,
- and said lower melting vessel being outwardly radially enlarged relative to the upper shaft part to form a radially enlarged part with at least one graphite electrode projecting laterally into said vessel in a region of said enlarged part, wherein said electrode is arranged at a level with respect to a vertical axis of said shaft furnace arrangement and a plurality of oxygen burner lances are symmetrically radially arranged with respect to said vertical axis and horizontally disposed adjacent to said electrode on at least one level located above a level on which said electrode is arranged, and
- wherein said shaft furnace arrangement also includes an electric arc hearth furnace disposed immediately and cooperatively adjacent to said shaft part and said lower melting vessel,
- said process comprising the steps of
- continuously melting a charge of said ferrous metal in said shaft furnace arrangement and thereby obtain a melt thereof,
- collecting said melt in said electric arc hearth furnace,
- processing said melt to steel, and heating and tapping in batches said electric hearth furnace to provide a steel product.
Dependencies are inferred from the claim text.