FORFARANDE OCH UGN FOR BEHANDLING AV INOM ICKE-JERN-METALLINDUSTRI ERHALLENSLAGG MED KOLHALTIGT REDUKTIONSMEDEL

摘要

A method comprising the steps of supplying a carbonaceous reducer in a layer onto the surface of molten slag and feeding an oxygen-free gas into said slag in an amount and at a rate ensuring recirculation of said slag with its outflow onto the surface of said carbonaceous reducer layer and filtration therethrough. An electric furnace for carrying into effect said method, comprising a space defined by walls resting on a hearth and supporting a roof wherein are fixed electrodes, devices for charging slag and a carbonaceous reducer into the furnace, and there are provided tuyeres adapted for supplying an oxygen-free gas into the slag, said tuyeres being spaced apart at a distance substantially equal to that of 3 to 6 electrode diameters, and at a distance of 1 to 3 electrode diameters from the furnace walls the bottom nozzle edges of said tuyeres being in space relationship with the horizontal axis of either a matte or metal tapping notches with a distance therebetween of 0.3 to 2 electrode diameters.