METALLURGICAL ADDITIVE AND MANUFACTURE THEREOF

摘要

PURPOSE:To manufacture a metallurgical additive contg. Mg and CaC2 by reducing a mixt. of carbonates or oxides of Mg and Ca with a carbonaceous reducing agent at a high temp., followed by rapid cooling with an inert gas. CONSTITUTION:Dolomite consisting of MgCO3 and CaCO3 or calcined dolomite consisting of MgO and CaO is reacted with a carbonaceous reducing agent such as coke or graphite at a high temp. in an electric furnace, etc., forming a reaction product contg. CaC2 and Mg vapor. The product is rapidly cooled with a gas such as He, Ar, N, H or CH4 to prevent reoxidation of the Mg vapor to MgO. By the cooling, fine powder is obtd. consisting of Mg; 5-55%, MgO; 3-40% and the balance CaC2, CaO and carbon. The powder is molded into granules or pellets with acrylic resin, etc. and used in desulfurization, dephosphorization, graphite spheroidizing, inoculation, etc. of molten pig iron.