Numerical Simulation of Decarburization Reaction with Oxygen Blowing During RH Refining Process

A mathematical model for the decarburization coupling with the fluid flow in the RH refining process was established. The decarburization reaction at three sites was considered, including the surface of injection lifting gas bubbles, the gas-liquid interface in the vacuum chamber and the interior of the molten steel bath. The effect of the flow pattern on the transfer of carbon and oxygen in the molten steel was obtained. The decarburization inside the molten steel bath in the vacuum chamber contributed the most, accounting for 55.9 pct of the total decarburization. The gas-liquid interface in the vacuum chamber and the surface of bubbles injected from the up-leg snorkel contributed approximately 32.5 and 11.6 pct, respectively. The oxygen blowing through the top of the vacuum chamber promoted the decarburization of RH refining whenever the oxygen was injected. When the oxygen was injected at the beginning of the decarburization process, the contribution of the decarburization at the top surface of the molten steel in the vacuum chamber to the total decarburization increased from 11.6 to 28.3 pct.