| 摘要 |
<p>PURPOSE:To retain Mn in molten iron in high yield by specifying the C concn. in molten iron at the close of refining, T.Fe in slag, slag basicity, blowing-out temp., and oxygen blowing rate at the time of melting a solid iron source with a carbonaceous substance as the heat source. CONSTITUTION:When a solid iron source (scrap, etc.), is melted in a reaction vessel with a carbonaceous substance as the heat source, the C concn. in molten iron at the close of refining is controlled to >=3.8%, the T.Fe in slag to <=2.0%, the slag basiscity to 1.0+2.0, and the blowing-out temp. to 1380-1450 deg.C. In addition, operation is carried out so that the equation, Voz=0.933Wc+Vfc, is established {Voz is the oxygen blowing rate (Nm<3>/t-min), Wc is the carbonaceous substance adding rate (kg/t-min), and Vfc is the secondary combustion oxygen (Nm<3>/t-min)}. By this method, the Mn in scrap can be retained in the molten iron in the high yield of about 7%.</p> |
