| 摘要 |
1,261,173. Arc furnace operation. FALCONBRIDGE NICKEL MINES Ltd. Jan.21, 1970 [Feb. 17, 1969], No.2841/70. Heading C7D. A method of melting material added to an arc furnace containing at least one vertically adjustable electrode positioned above the molten bath comprises striking an arc between the bath and the electrode, feeding particulate material such that a mass of particles surrounds the arc, thereby shielding the arc and establishing a confined high temperature melting zone, continuously flowing the material through the zone, so that the particles melt and flow into the bath, the molten bath being tapped at least periodically, a major portion of the power supplies to the furnace being released in the arc. Preferably nickelferrous ore of the oxide or silicate type is used, a neutral or arc stabling atmosphere provided, the slag produced being removed continuously and the ferronickel intermittantly. The depth of the bath is preferably low e.g. 1-2 feet, the voltage high, the particles preheated to e. g. 700‹ C. and the length of the arc such as to have a resistance per phase of at least 0À02 ohms. Particles having sizes up to ¢ inch, or agglomerates of particles such as briquettes, pellets and pieces may be used. The particles may also contain free metal and carbon in limited quantities. In an example particles containing Fe, Ni, MgO, SiO 2 , CO, C and S are used. |
