Study And Application Of High-efficient Dephosphorization In 120t Blowing Converter

The content of phosphorus in steel is too high, it is easy to cause the product to crack when it is solidified. For the high grade steel need to be phosphorus down to 100 ppm, and for the use of pipeline steel in a very cold area, to prevent the cold brittleness, and even the need to control the phosphorus content of steel in the following 50 ppm. Ironmaking process for reducing atmosphere, basically do not have the ability of dephosphorization, thus dephosphorization is one of the important tasks in the process of steelmaking.This paper mainly from the thermodynamics and kinetics of converter smelting analysis, discusses the 120 t combined blown converter single slag method, double slag method and double method in the smelting process of slag basicity, temperature, FeO and effects on phosphorus content control of Si content in molten iron and other. Analysis of phosphorus, and three smelting method for dephosphorization efficiency comparison for Laiwu Steel steel MINIMILLS 120 t combined blown converter smelting data analysis of the three methods of operation in the slag basicity, temperature, FeO) and the content of Si in molten iron effect on P content control and on the advantages and disadvantages of the three methods were analyzed.The results show that the double method in dephosphorization are superior to single slag method and double slag method, obvious effect, easy single slag production organization. Through the optimization of single and double double slag slag, mode of operation, the type of Laiwu Steel MINIMILLS 120 t rate reached more than 92% BOF dephosphorization. For the production of Laiwu Steel MINIMILLS ultra-low phosphorus steel foundation.