A new model for the simulation of the converter steelmaking process was developed after the detailed study of existing thermodynamic and kinetic models and approaches. This model consists of the reaction model and models for charge materials melting and dissolution. The reaction model is based on the coupled reaction model, which includes the combination of both thermodynamics and kinetics of the involved phases. The models of charge material melting and dissolution include the definition of the driving force for the melting and dissolution, and the mass transfer coefficients in the metal and slag phases.

In order to validate the BOF process model, the heats in 170-and 330-ton converters were simulated. The different types of heats in a 170-ton converter were considered. The model validation includes the comparison of the actual and simulated end blow parameters. The behaviors of the metal and slag phase components, temperature and charge material melting, and dissolution were shown and analyzed. The end blow chemical composition of steel and the temperature were simulated quite accurately. Small deviations between actual and simulated results were found for the end blow chemical composition of slag. Using the simulation results, the oxidation-reduction behavior of phosphorus and manganese during the converter steelmaking process was explained.

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The EU commission has committed to fulfil the targets of greenhouse gas (GHG) emission reduction in 2050 by 80% in comparison to the level of 1990. The fulfilment of the EU's climate policies brings new challenges for the iron and steel industry. The European steel industry is forced to develop strategies for the transition of their technology to a carbon lean production and to keep the competitiveness in the world market. The steel companies in EU27 are taking the challenge to secure the steel production in Europe and have launched innovation projects for CO2 mitigation with the focus on the technological pathways Carbon Direct Avoidance (CDA) and Smart Carbon Usage (SCU), which are, beside Circular economy, defined as important pillars for CO2 abatement in European steel industry. The transformation of the steel industry must go hand in hand with a decarbonisation of the energy supply and other industries within EU27.

Precipitation kinetics of Nb(C,N) in microalloyed steels is crucial for the achievement of favoured steel properties. Therefore, numerous experimental studies have been performed in the past and various theoretical models have been developed to describe Nb(C,N) precipitation. However, the experimental data is sometimes contradictory and even the thermodynamic data for NbC solubility in austenite have a large scatter. In this paper, experimental results on the Nb(C,N) and NbV(C,N) precipitation kinetics in deformed and undeformed austenite are reviewed. Based on these data and with the precipitation kinetics module of the software package MatCalc, computer simulations are performed. The predicted interfacial energy of precipitates is adjusted to match the observed kinetics. A comparison between experimental information and simulation, l.e, time -temperature -precipitation (TIP) diagrams, is drawn and discussed. The results of the computer simulations using modified interfacial energies are in good agreement with the experiments.