METHOD FOR SMELTING LOW-P CONCENTRATION CHROMIUM-CONTAINING MOLTEN METAL BY SMELTING REDUCTION

摘要

PROBLEM TO BE SOLVED: To smelt low-P concn. chromium-containing molten metal without being accompanied by the oxidation loss of chromium by specifying the charging amt. of carbon, molten iron temp. and the stirring driving power density by a bottom blowing gas at the time of smelting reduction of chromium oxide. ;SOLUTION: The smelting reduction of the chromium oxide is executed by charging the chromium oxide, carbon source and flux into a steel bath charged into a top and bottom blown refining vessel. At this time, the ratio (the amt. of the carbon/the amt. of the chromium oxide) of the charging amt. of the carbon to the chromium oxide is adjusted to 1.0 to 3.0 and the molten iron temp. is adjusted to ≤1500°C. The operation is executed under such conditions under which the stirring driving power density ε by the bottom blowing gas determined by the equation satisfies 5 to 30kW/t. In the equation, Q denotes the flow rate (Nm³/min) of the gas, T denotes the temp. (K) of the molten metal, W_m denotes the weight (t) of the molten metal, h denotes the blowing depth (cm) of the gas, P denotes the pressure (Torr) of the atmosphere. The low-P concn. chromium-containing molten metal is smelted without the need for using a flux for dephosphorization, etc., according to this method.;COPYRIGHT: (C)1997,JPO