Electric arc furnace and method of operating same

An electrical arc furnace (100) for a quasi-continuous operation, comprising:

• a lower vessel (100) for melting iron carries, wherein the lower vessel has a tapping device (115) for tapping melt;
• a lid (120) placeable on the lower vessel and having a first opening (122) for receiving at least one electrode (130), and at least one second opening for charging iron carriers and additive in the electrical arc furnace;
• the at least one electrode (130) extending vertically through the first opening (122) and into an interior of the electrical arc furnace;
• an electrode holding device (140) for holding the at least one electrode (130);
• and
• a supply voltage device (150) for making available an electrical supply voltage for the at least one electrode (130);
• wherein the electrode holding device (140) has an electrode adjusting device (142) for adjusting the at least one electrode and
• an electrode nippling device (144) for nippling the at least one electrode (130) for adjusting the at least one electrode in accordance with its wear and for nippling the at least one electrode, respectively, during operation of the electrical arc furnace,
• wherein the tapping device (115) is so arranged on the lower vessel (110) that a regular tapping is possible when the lower vessel is upright and stationary, and
• wherein the supply voltage device (150) is formed as d.c. voltage source or a.c. voltage source for making available supply voltage for the electrode in form of d.c. voltage or a.c. voltage, and
• wherein the supply voltage device (150) has a transformer (152) which is located directly above the at least one electrode (130), the at least one electrode (130) being connected with the transformer (152) by a conductor (130a) extending vertically between the at least one electrode (130) and the transformer (152).

A method of operating, in a quasi-continuous operation, an electrical arc furnace (100) having a lower vessel (110), a lid (120) placeable on the lower vessel and having a first opening (122) for receiving, at least one electrode (130), the at least one electrode being displaceable through the first opening (122) in the lid (120) into an interior of the electrical arc furnace, and at least one second opening (124), and a supply voltage device (150) having a transformer (152) located directly above the at least one electrode (130), wherein the at least one electrode (130) is connected with the transformer (152) a conductor (130a) extending vertically between the at least one electrode (130) and the transformer (152), the method comprising the following steps:

• charging iron carriers or additives into the electrical arc furnace through the at least one second opening (124) in the lid,
• time-continuously feeding supply voltage from the transformer to the at least one electrode (130) for melting an iron carrier introduced into the electrical arc furnace for the continuous operation of the electrical arc furnace over several melts, and
• adjusting and nipping that at least one electrode during operation of the electrical arc furnace, and
• wherein tapping of the melt takes place at the upright and stationary lower vessel (110).