Study of the erosion of ladle refractories when gas is injected deep into the bath through a rotating lance

With the use of isothermal modeling, new data were obtained regarding the influence of the movement of gas jets from the nozzles of the tip of the submersible rotating lance on the hydrodynamics and the intensity of mass transfer processes in the ladle bath. It was established that mixing the bath during the rotation of gas jets increases the mass transfer rate, since the tangential stress arising in the liquid causes the gas bubbles to be crushed, which in turn leads to an increase in the volume of the bubbling zones and the reaction surface of the phases. The increase in the total volume of the bubbling zones is 25-35% of the volume of the bath, compared to 8-10% for a stationary nozzle. Peculiarities of erosive wear of the ladle lining during desulfurization by blowing powdered reagents through the nozzles of T-shaped nozzles of lances were investigated. The highest intensity of wear with increasing gas consumption is observed in the upper part of the bucket. With an increase in the rotation speed of the lance and gas consumption, the intensity of wear decreases in the middle horizons from 0.7 to 0.4 mm/min. For the upper areas of the bucket, increasing the gas consumption from 1.0 l/min to 2.2 l/min and the rotation speed to 120 rpm leads to a decrease in intensity by 36.7%, for the middle – by 55.6%, for lower – by 28.5%. Based on the results of a comparative analysis of the wear profile of the working layer of refractories when using stationary and rotating lances and numerical modeling of the dynamics of wear, the rational consumption of the carrier gas and the rotation speed of the lance were determined to minimize the intensity of lining erosion. From the point of view of dispersing the desulfurizing reagents with a simultaneous increase in the gas saturation of the bath, it is advisable to increase the gas consumption and the rotation speed of the lance to the maximum possible values. On the other hand, from the point of view of preventing uneven wear of the lining, it is advisable to limit the speed of rotation of the gun at the level of 60-75 rpm, and gas consumption - by the need to ensure a stable mode of formation of the gas powder flow without clogging the nozzles of the T-shaped tip of the lance