Fundamental Mathematical Model for AOD Process. Part II: Model validation

Abstract

A fundamental mathematical model for AOD process has been developed and proposed in ''Fundamental Mathematical Model for AOD Process. Part I: Derivation of the Model'' [1]. Validation of the model with process data, measured from full scale AOD process, is presented in this paper.A broad selection of input data for the model was exported from various types of full scale industrial AOD heats. In this study 6 different types of heats were studied and simulated. Process data was measured from two AOD converters (95 t, 150 t). Validation of the model was then done by comparing simulated and measured values for carbon and chromium content, carbon release rate, melt composition, slag composition and bath temperature during final stages of carbon removal.The validation results showed that the model was in good agreement with the measured process data, and same model parameters were valid in all of the simulated heats.

A Mathematical Model for the Reduction Stage of the AOD Process. Part II: Model Validation and Results

“…It should be noted that initial temperatures used in the simulations were the maximum temperatures that could be measured by the temperature probe before its breakdown, and thus it is obvious that the predicted end temperatures of the steel bath must be lower than the measured ones. However, previous modelling results 8) suggest that the actual initial bath temperature should be less than 2 100 K.…”

“…Then, using an approach based on the modified law of mass action, a new mathematical model for the reduction stage was proposed and coupled with the mathematical model for side-blowing decarburisation developed by Järvinen et al 7,8) This paper, Part II, focuses on the validation of the model with full-scale production data from a 150 t AOD converter at Outokumpu Stainless Oy, Tornio Works, Finland.…”

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

“…The studied applications in the AOD process include mathematical modelling of reactions in a single gas bubble in liquid steel, 19) during side-blowing decarburization 20,21) and during the reduction of slag. 22,23) The method has also been applied for mathematical modelling of chemical heating in the CAS-OB process.…”

A Mathematical Model for the Reduction Stage of the AOD Process. Part I: Derivation of the Model

“…Many of the older models assumed that all the blown oxygen is consumed immediately in the oxidation reactions, [13][14][15][16][17] although some allowed the accumulation of unabsorbed oxygen in the steel melt. 3,8,9) The models proposed by Wei & Zhu 19,20) and Järvinen et al 6,7) allow the oxygen to either react, accumulate or escape the bath, although Wei & Zhu employ a predetermined constant for the proportion of escaping oxygen. However, the most significant improvement provided by these models is the assumption that all the oxidation-reduction reactions take place simultaneously at the reaction interface.…”

“…Järvinen et al [5][6][7] have presented a process model, which considers mass transfer -controlled reactions and locally varying conditions in the plume zone. This model can be used to describe decarburisation and slag formation during the side-blown decarburisation stage of the AOD process.…”