METHOD OF CHEMICALLY HEATING STEEL IN LADLE Russian patent published in 1998 - IPC

FIELD: steelmaking. SUBSTANCE: invention relates to out-of-furnace treatment of smelted steel before continuous casting. Into the ladle with steel, aluminum wire is fed with velocity 5-10 m/s and total uptake 0.4 to 4.0 kg per 1 t steel. When 5-25% of the total aluminum uptake is consumed, steel begins to be blown by oxygen with oxygen uptake varying from its maximum value equal to 0.15-0.25 cu.m/min t in the beginning of blowing to its minimum value 0.06-0.08 cu.m/min t at the end of blowing. Rest of aluminum is added with current uptake proportional to varying current oxygen uptake according to dependence q= (2.5-12)Q, where q is current aluminum uptake, kg/min t, Q current oxygen uptake, cu.m/min t, and 2.5-12 empirical coefficient of proportionality characterizing physico-chemical regularities in observing necessary stoichiometric ratio of current uptake values for aluminum and oxygen, kg/cu.m. Oxygen-blowing lance may be immersed under steel level to the value equal to 0.2-0.8 height of steel column in the ladle. In the case of preliminarily adding aluminum, steel in the ladle may be blown by a neutral gas with uptake 0.08- 0.16 cu.m/h t. EFFECT: optimized process parameters. 3 cl, 1 tbl