Electric smelting furnace for nonferrous metal smelting and method of charging raw slag

摘要

PURPOSE: To separate and recover metallic component contained in molten slag at high yield by decreasing the discharging speed of the molten slag from an ore smelting furnace and supplying into an electric slag smelting furnace, at the time of smelting non-ferrous metal from sulfide mineral. CONSTITUTION: Sulfide concentration of the non-ferrous metal of copper, etc., is smelted in the smelting furnace to produce a matte composed of sulfide metal of copper sulfide, etc., and the molten slag. Since the fine granular matte exists while suspending in the molten slag, the slag is flowed into the electric slag smelting furnace 2 through slag troughs 3 and heated by conducting the electric power with the electrodes 5, and the fine granular matte in the slag is precipitated with sp. gr. difference and extruded and recovered from matte holes 2a. In the case, a water-cooling jacket 4 made of a metal of copper, etc., having good thermal conductivity is arranged at the tip part of the trough 3 for pouring the molten slag and the molten slag is not directly directed to the slag holes 2b but dropped into the electric slag smelting furnace in the vertical direction by making the molten slag from the through 3 collide to decrease the speed in the horizontal direction, and the fine granular suspension of the matte staying therein is precipitated and recovered in good yield.