Simulation Of Argon-Blown Gold Flow And Inclusion Movement Behavior At The Bottom Of The 60t Ladle

Argon blowing at the bottom of ladle plays an important role in iron and steel smelting,which can greatly improve the purity of liquid steel.When argon is blowing at the bottom,the technical parameters such as the location of breathable brick and the flow rate of bottom blowing play an important decisive role in the utilization rate of argon gas and the refining effect.In this thesis,a 60-t ladle in a steel plant was used as the prototype,and a physical model of 1:4 was established to study the effects of blowing flow rate,location of breathable brick and thickness of slag layer on mixing time and slag rolling.In addition,a mathematical model was established relying on commercial software.On the premise of comparing and verifying the accuracy of the model,the influences of the blowing flow rate and the location of the breathable brick on the ratio of dead zone in ladle and the removal efficiency of inclusions were further studied.The main research results are as follows:(1).In the physical experiment of single-hole bottom blowing of ladle,the flow rate of bottom blowing is 200 L/min,the position of bottom blowing is 0.6r,and the thickness of slag layer is 30 mm(corresponding to the prototype 120 mm),which is the most conducive to shorten mixing time,slow down the occurrence of slag rolling and reduce the exposed area of liquid steel.In the numerical simulation study,when the bottom blowing flow rate is 300 L/min and the bottom blowing position is 0.6r,the proportion of dead zone is the smallest(9.8%),and the ladle mixing efficiency is the highest.For inclusion removal effect,when the bottom blowing flow rate is 200L/min and the bottom blowing position is 0.6r,the inclusion removal effect is better.Considering the mixing time,slag behavior,dead zone and inclusions,the optimal flow rate of single hole bottom blowing was determined to be 200 L/min,the bottom blowing position was 0.6r,and the thickness of slag layer was 30 mm.(2).In the physical experimental study of double hole bottom blowing of ladle,the bottom blowing flow rate of 200 L/min and 300 L/min of exposed liquid steel is the most beneficial to shorten mixing time,slow down slag rolling and reduce the double hole bottom blowing position is arranged at 0.6r;In the numerical simulation study,when the bottom blowing flow rate is 300 L/min and the bottom blowing position is 0.6r,the turbulent kinetic energy distribution in the ladle is more uniform,the stirring efficiency is high,the dead zone is less,and the removal effect of 10 um inclusions and 50 um inclusions is better.When the connection Angle between the double breathable brick and the bottom center of the ladle is 45°,the proportion of dead zone in the ladle is the smallest,and the inclusion removal effect is the best.The proper reduction of the included Angle is more conducive to the reduction of dead zone and the floating of inclusions.Considering the mixing time,slag behavior,dead zone and inclusion,the optimal flow rate of double-hole bottom blowing was determined to be 300 L/min,the bottom blowing position was 0.6r,and the Angle between the breathable brick and the center line at the bottom of the ladle was arranged to be 45°.