Simulation study on fluid flow performance of injection stirring composite process in molten iron desulfurization process

The blowing and stirring composite process of molten iron desulfurization process affects the desulfurization efficiency and has obvious advantages in improving steel properties and expanding the scale of converter steelmaking. At present, the injection position of the injection stirring research is fixed, and the desulfurization efficiency needs to be improved. The gas–liquid flow behavior of single-scale bubble model and the size and distribution of bubbles in multi-scale bubble model were studied by computational fluid dynamics numerical simulation method for the injection mixing composite process of jet inlet and stirring paddle rotating at the same speed. The pressure distribution and velocity distribution inside the fluid indicate that the velocity difference between the gas–liquid phases and the turbulence of the liquid are due to the collisions of bubbles, which are due to essential conditions for bubble breaking. Different injection air volumes have essential influence on the formation of single bubbles. When the injection volume reaches 2.8 m3/h, the turbulent kinetic energy is maximum, the bubble formation is rapid, and the desulfurization efficiency can be improved. The multi-bubble results show that the bubble diameter is mainly distributed in the range of 2–5 mm. The higher gas flow rate will increase the number of bubbles in the fluid and promote the bubble refinement process.