Different from other conventional large converter in Shougang, Shougang 100 t low flow bottom blow converter is easy increasing the phosphorus in the furnace before steel tapping, especially low carbon steel smelting. For this phenomenon, The effect of the presence of solid phosphorus-rich phase C2S-C3P on the phosphorus distribution ratio was investigated, test and calculation shows that solid phosphorus-rich phase in slag can improve the phosphorus distribution ratio. The reason is that the nature of the steel slag changed, it is mainly due to the reduction of the phosphorus-rich phase C2S-C3P in the slag, in addition, the change of iron water Si content in the converter has a certain impact on the phosphorus content at the converter end point, smelt the low phosphorus steel by double slag method, when the silicon content is below 0.40 % every 0.10 % reduction in Si content, the P content increase about 10 ppm. In addition, the oxygen supply is too high, it also easily leads the increasing of P at the end point , the main reason is FeO increasing and reduce C2S-C3P in furnace slag , This results in increased phosphorus in liquid slag, resulting in redistribution of P between slag and steel.
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