| 摘要 |
<p>PURPOSE:To efficiently dephosphorize low-Si pig iron, by blowing and charging specified amounts of a powdery refining agent and a fluxing assistant to the low-Si pig iron in a bottom-blown converter, and holding the pig iron at a specified temperature by charge of a cooling agent. CONSTITUTION:Low-Si molten pig iron containing 0.15wt% or less of Si is poured into a bottom-blown converter, a powdery refining agent is injected by bottom-blowing refining gas as a carrier, a fluxing assistant is charged through the top opening of the vessel, and the temperature of the molten pig iron during blowing is held and controlled at 1,250-1,450 deg.C by charge of a cooling agent. In order to attain a dephosphorizing ratio of about 85% or more, 12kg or more of the powdery refining agent of calcium oxide powder is blown in, and 2kg or more of the fluxing assistant comprising at least one or fluorite, soda ash, cryolite, colemanite and red mud is charged. As the cooling agent is used at least one of iron ore, mill scale and scrap.</p> |
