PROCESS FOR REFINING INTO STEEL PIG IRON POOR IN PHOSPHORU

1403058 Converter steel-making EISENWERK-GES MAXIMILIANSHUTTE mbH 7 Dec 1972 [7 Dec 1971] 56438/72 Heading C7D A method of refining a low-phosphorus pig iron melt in a converter comprises blowing a suspension of powdered lime in O 2 into the melt through the inner of a pair of coaxial nozzles projecting through the lining of the converter below the melt surface, a liquid or gaseous hydrocarbon being blown through the outer nozzle as a protective. Suitable hydrocarbons include CH 4 , C 3 H 8 , C 4 H 10 , C6H6, alcohol, kerosene, natural gas, coke oven gas, and light fuel oil, preferably up to 10% of the O 2 . Prior to the above process, lime may be blown in with N 2 or Ar, again surrounded by a hydrocarbon, to effect desulphurization. The lime may be added in batches, or continuously in varying amounts. A fluxing agent, e.g. fluorite, feldspar, bauxite may also be added to the O 2 stream.