Apparatus for continuously refining molten metals

Device for continuously refining molten pig iron with oxygen and an addition of lime resulting in separate bodies of molten metal and slag comprising a reaction vessel having at least a first and a second refining stage portions each including an inlet into which liquid metal is continuously feedable, a outlet for separately removing molten metal and slag and an interconnecting section providing flow therebetween, each of said first and second refining stage portions forming a passage from the inlet through the interconnecting section to the outlet having a lower liquid level defining the upper level of the molten metal

• and an upper liquid level defining the upper level of a layer of slag with the layer of slag located between the lower liquid level and the upper liquid level, means providing communication between said refining stage portions including a slag duct for passing out of the outlet of said second refining stage portion and into the inlet of said first refining stage portion at least part of the layer of slag therein, said slag duct having one end opening into said first refining stage portion and another end opening into said second refining stage portion at an elevation thereof higher than at which said one end opens into said first refining stage portion, at least one gas supply tube communicating with each of said first and second refining stage portions, and means for discharging slag and liquid metal from said reaction vessel, said discharge means comprising openings spaced vertically from one another with one of said openings located in said first refining stage portions and the other said opening located in said second refining stage portion.