Verfahren und Vorrichtung zum Betreiben eines Doppelgefäß-Lichtbogenofens

摘要

A process for operating a double-vessel arc furnace (esp. for steel-making), with electrodes mounted on a swivel mechanism, involves operating a first vessel (1) by: (a) charging liq. pig iron in amount up to 70% of the metal charge in the vessel (1); (b) oxygen blowing using a lance (14) passing through the furnace lid (4) while adding coolants (e.g. ore, scrap, sponge iron or other metallic charge materials), according to the heat balance of the blowing operation, and slag-formers (e.g. lime dolomite, etc); (c) continuously slagging off and/or partially slagging off during blowing interruption and/or at the end of blowing, through the slagging door and through the preheater during step (b); (d) lifting and swinging away the lance (14,16) from the vessel (1); (e) swinging the electrodes (3), connected to a high current lead (9) from a transformer (10) onto the vessel (1) using the swivel mechanism (8); (f) supplying the electrodes (3) with current while adding the remaining charge materials (ore, scrap, sponge iron or the like), until the tapping wt. is attained, and lime addns. and further blowing with side oxygen lances during the melting down and superheating operations; (g) continuously partially slagging off and/or partially slagging off, during the process and/or its end, through the slagging door and through the preheater during step (f) with subsequent superheating of the melt; and (h) tapping the melt into a steel pouring ladle through the taphole (23), part of the melt being left as a heel in the vessel hearth. The second vessel (2) is operated by: (i) carrying to the steps (e) to (h) in the vessel (2) while steps (a) to (d) are being carried out in the first vessel (1); and (ii) carrying out steps (a) to (d) in the vessel (2) while steps (e) to (h) are being carried out in the first vessel (1). Also claimed is a double-vessel arc furnace for carrying out the above process.