摘要 |
<p>A steelmaking process for desiliconizing, dephosphorizing, desulfurizing and decarburizing molten iron from a blast furnace is disclosed, which comprises the sequence of the following treatments: (1) The first step of agitating or stirring the molten iron in a reaction vessel, supplying the molten iron with both gaseous oxygen and solid oxygen, reducing the Si content of the iron to a value between 0.05 and 0.20% at a controlled bath temperature between 1480 and 1380.degree.C, and discharging the resulting slag; (2) the second step of agitating or stirring the molten iron from the first step having a bath temperature between 1480 and 1380.degree.C supplying the molten iron with a flux mainly consisting of 0.2 to 0.5 parts by weight of CaC12 or KC1 or both CaC12 and KC1 per part by weight of CaO and a source of oxygen, maintaining the basicity of the processing slag between 3.5 and 8.0 and the T.Fe level between 3 and 10%, desulfurizing and dephosphorizing the iron with the same slag to reduce the P, S and Si contents to not higher than 0.025%, 0.020% and a trace, respectively, and to hold the C content not lower than 3.8%, and discharging the resulting slag; and (3) the third step of decarburizing the molten iron from the second step by blowing oxygen onto the-melt without using a refining flux.</p> |