Simulation and Application of Top-blowing Lance with Various Inclination Angles in Decarburization Ladle Furnace

Abstract

To reduce the production costs of ultra-low carbon steel, an oxygen lance has been employed in a 150 t decarburization ladle furnace. This study conducted both water experiments and numerical simulations to examine the flow field characteristics and stirring effects of the top-blowing lance at various inclination angles of 4°, 6°, 8°, and 10°. The results indicated that a smaller inclination angle enhanced the mixing effect and impaction depth of the molten bath, whereas the impaction diameter exhibited a contrasting trend. The behavior of the oxygen multi-jets suggested that a smaller inclination angle mitigated the loss of kinetic energy, thereby improving impaction ability. As the depth of the molten bath increased, the average velocity of the molten bath section displayed a trend characterized by an initial rapid decrease, followed by a gradual decline, and culminating in a subsequent rapid drop. In industrial application research, the 4° oxygen lance resulted in a shorter decarburization time compared to the 8° oxygen lance. This reduction in decarburization time led to decreased heat energy loss due to the heat-absorbing effect of ambient gas, which further enhanced the end-point temperature of the molten bath.