Numerical Simulation And Optimization On 100t Bottom-blowing Argon Ladle With Immersed Cylinder

The national economy departments of the increasing requirements about the quality of the steel, the growing demand for high quality steel and clean steel, high efficiency and low cost of steelmaking process and the market demands, high quality steel and pure steel demand is growing, and the market for steelmaking processes of high efficiency and low cost requirements, only by the blast furnace-converter, electric furnace to produce qualified steel technology has basically become history with the progress of science and technology. Ladle bottom blowing argon stirring technology, due to its simple equipment, flexible operation, good uniformity steel composition, temperature, improve the reaction of dephosphorization and desulphurization, efficient removal of steel inclusions and harmful gases, improve the refining effect of liquid steel in the furnace, etc. is widely used in the secondary refining. But the bottom blowing cause excessive splashing of liquid steel, slag entrapment and the problem of secondary oxidation of molten steel, limiting the amount by increasing the bottom blowing to increase refining effect.In this paper, adopts a domestic steel mills of 100 t bottom-blowing argon ladle as the prototype, application of three dimensional continuity equation, momentum N-S equation and turbulence ??- two equation to simulate the bottom blowing argon ladle in the process of the liquid steel flow state. Using the mixture multiphase flow model to simulate the single-hole blowing argon process, comparative analysis the flow of the molten state and the phenomenon of liquid steel slag entrapment before and after immersion cylinder. Analysis the influence of molten steel flow and slag layer flow state of liquid steel surface, and blending with immersed cylinder, determine the critical amount of slag gas blowing. The results show :1. Without immersion cylinder, ladle have emerged large disadvantaged areas in the middle and lower, gas-liquid two phase velocity is larger, uneven distribution of flow field inside the package, increasing the amount of blowing just increases the flow rate of liquid steel, but the circulation center is essentially the same, circulation center of liquid steel is between 0.6 ~ 0.7 H; After inserting the immersion cylinder, changing the circulation flow within the ladle, circulation center of liquid steel is between 0.6 ~ 0.7 H, circulation center speed increases, reducing the disadvantaged regions, steel liquid velocity distribution is more uniform, mixing time can be shortened.2. Critical volume slag blowing amount is 102 L / min without immersion cylinder, after inserting diameter 691.05 mm, 650 mm deep immersion cylinder,the critical volume of slag blowing amount is increased to 217 L / min. We can increase liquid steel stirring effect under conditions of increasing the amount of argon.3. Argon gas quantity of 204 L/min, there is greater internal ladle vulnerable areas without immersion cylinder, gas-liquid two-phase region velocity is larger, and therefore the flow velocity distribution is uneven, the maximum speed is 0.5 m / s, while the vast majority of molten steel velocity in ladle flow within 0 ~ 0.3 m/s; Ladle bottom blowing argon circulation center vulnerable area is decreased, and the steel flow velocity is uniform, most of flow velocity distribution in the 0.1 m/s ~ 0.4 m/s, the average speed is increased, liquid steel circulation mixing enhancement, with immersion cylinder.4. After inserting the immersion cylinder, mixing time can be shortened to enhance smelting effect.