Increasing chromium/iron ratio in iron - contg chromite ores

摘要

Process comprises reducing a major part of iron to the metallic state by means of carbon as a reducing agent in the presence of a sulphur cpd. under such conditions that the Fe-Cr-S system separates into two phases at 1400-1500 degrees C, the Fe-rich phase (low sulphur content) agglomerates into droplets and is separated, after cooling, by physical methods, the temp. being reduced slowly by 100-200 degrees C, and then rapid cooling being applied). The solubility gap in the Fe-Cr-S system can be influenced by suitable additives. By this method, the Cr:Fe ratio in the ore can be increased to 3 or more.