In this study, a thermodynamics model was evolved for the Vacuum Oxygen Decarburisation (VOD) process (combined top and bottom blown), which was utilised to evaluate the transient carbon, silicon, manganese, and chromium contents, as well as their slag composition. The Vacuum Oxygen Decarburisation (VOD) process is highly dynamic, inhomogeneous and intricate, playing a crucial role in stainless steel production, therefore a dynamic model was developed, incorporating multiple zones to better capture the inhomogeneous behaviours of the VOD process. The macro programming facility of FactSage™ software has been utilised to realise the thermochemical and kinetics of the Vacuum Oxygen Decarburisation. The model-predicted values for chromium, manganese, carbon, and silicon closely align with the plant data.
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