Simulation of Steel Refining Process in Converter

Abstract

Steel refining is a complex phenomenon which depends on numerous variables, so, a kinetic approach is necessary for precise understanding of the refining process. In this study, based on a previously proposed model for hot metal dephosphorization, a new simulation model for the steel refining process in BOF is presented. In most cases, steelmaking slag is saturated with dicalcium-silicate (C 2 S) and it is well known that C 2 S forms solid solution with tricalcium-phosphate (C 3 P) in a wide composition range and the partition ratio of phosphorus between C 2 S and liquid slag is large. On the other hand, C 2 S formed around the lime surface is known as a barrier to lime dissolution into liquid slag. In this simulation model not only the effect of solid phase in slag is considered but also the effects of temperature dependence of variables as well as top and bottom blowing and scrap melting are taken into account.The calculation results are compared with industrial data and the good agreement between experimental and simulation results evidence the validity of this kinetic approach to steel refining process in BOF. Moreover, by using this model the influence of various parameters on the reaction efficiency is discussed. steel research int. 81 (2010) No. 8 Process Metallurgy Figure 8. a) Effect of Ar flow rate and b) effect of oxygen flow rate on the relation between carbon content and free oxygen.

Behavior of Vanadium and Niobium during Hot Metal Dephosphorization by CaO–SiO₂–Fe_tO Slag

“…Details about the model can be found elsewhere; 12,13,[15][16][17] therefore, in this study, we only provide a brief description. In this model, three phases: solid slag, liquid slag, and liquid metal and the reaction between the solid slag and the liquid slag are considered as well as the reaction between the liquid slag and the liquid metal.…”

“…Then, the behaviors of V and Nb in hot metal dephosphorization by CaO-SiO2-FetO slag were investigated. Finally, a previously described hot metal simulation model 12,13) was modified and the behaviors of various elements, including V and Nb, during hot metal dephosphorization were simulated, and the results were compared with experimental ones.…”

Law of Mass Action Based Kinetic Approach for the Modelling of Parallel Mass Transfer Limited Reactions: Application to Metallurgical Systems

“…[36][37][38] In this approach, the equilibrium constants are modified to effective equilibrium constants, which in combination with electro-neutrality condition, are employed to solve a system of parallel mass transfer limited reactions.…”

Enhancement of Quicklime Dissolution in Steelmaking Slags by Utilizing Residual CO₂ from Quicklime

“…The dissolution rate of these oxides in a molten slag plays an important role in increasing the reaction rate between the steel and slag, decreasing the amount of flux and energy consumptions, and reducing slag emission, and so on. Though the rate of lime dissolution affects the rate of phosphorus removal from the hot metal, [1][2][3][4][5][6][7][8] a part of the lime added as a flux, still exists without dissolution after steel refining. The low dissolution rate of lime during the pretreatment process of hot metal became particularly evident after the restrictions concerning the use of fluorites came into effect.…”