Abstract: A direct current electric arc furnace for melting or heating raw material or molten material includes a refractory lined vessel for holding raw or molten material in its interior. The furnace includes at least a first top electrode. The first top electrode enters the vessel interior above the raw or molten material. The furnace includes at least a first bottom electrode mounted in the bottom of the vessel and in electrical contact with the raw or molten material in the vessel. The furnace includes an electrical power supply mechanism which electrically connects to the top electrode and the bottom electrode in order to input electrical energy into the material through the top and bottom electrodes in the form of an arc. The bottom electrode has opposite electrical polarity to the electrical polarity of the top electrode. The furnace also includes a mechanism for cooling the first bottom electrode with a spray of water and air that contacts the first bottom electrode.

Abstract: A direct current electric arc furnace for melting or heating raw material or molten material. The furnace includes a refractory lined vessel for holding raw or molten material. The vessel has at least an old furnace shell having a bottom electrode which is replaceable with a new furnace shell having a bottom electrode such that the new furnace shell is placed in an operating position and replaces the old furnace shell. The furnace includes at least a first top electrode. The furnace includes at least a first bottom electrode mounted in the bottom of the vessel and in electrical contact with the raw or molten material in the vessel. The furnace includes an electrical power supply mechanism which electrically connects to the top electrode and the bottom electrode in order to input electrical energy into the materials through the top and bottom electrode and the form of an arc. The bottom electrode has opposite electrical polarity to the electrical polarity of the top electrode.

Abstract: A direct current electric arc furnace for melting or heating raw material or molten material. The furnace includes a refractory lined vessel for holding raw or molten material in its interior. The furnace includes at least a first top electrode. The first top electrode enters the vessel interior above the raw or molten material. The furnace includes at least a first bottom electrode mounted in the bottom of the vessel and in electrical contact with the raw or molten material in the vessel. The furnace also includes an electrical power supply mechanism which electrically connects to the top electrode and the bottom electrode in order to input electrical energy into the material through the top and bottom electrodes in the form of an arc. The bottom electrode has an opposite electrical polarity to the electrical polarity of the top electrode. The furnace includes a mechanism for stirring the molten material in the vessel and guiding the arc in the vessel.