Water model experiment of removal of inclusions in liquid steel by bubble flotation

Continuous casting is one of the steel production stages, during which the improvement in the metallurgical purity of steel can be additionally affected by removing nonmetallic inclusions (NMIs). This can be achieved by means of various types of flow controllers, installed in the working space of the tundish. The change in the steel flow structure, caused by those flow controllers, should lead to an intensification of NMIs removal from the liquid metal to the slag. Therefore, it is crucial to understand the behavior of nonmetallic inclusions during the flow of liquid steel through the tundish, and particularly during their distribution. The presented paper reports the results of the modeling studies of NMI distribution in liquid steel, flowing through the tundish. CFD modeling methods—using different models and computation variants—were employed in the study. The obtained CFD results were compared with the results of laboratory tests (using a tundish water model). The results of the performed investigations allow us to compare both methods of modeling; the investigated phenomena were microparticle distribution and mass microparticle concentration in the model fluid. The validation of the CFD results verified the analyzed computation variants. The aim of the research was to determine which numerical model is the best for describing the studied phenomenon. This will be used as the first phase of a larger research program which will provide for a comprehensive study of the distribution of NMIs flowing through tundish steel.

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Water Model Experiment on the Behavior of an Argon Bubble Rising Near the Immersion Nozzle

Tetsu-to-Hagane ◽

10.2355/tetsutohagane.94.271 ◽

2008 ◽

Vol 94 (8) ◽

pp. 271-277 ◽

Cited By ~ 4

Author(s):

Tsuyoshi Watanabe ◽

Manabu Iguchi

Keyword(s):

Model Experiment ◽

Water Model ◽

Argon Bubble ◽

Bubble Rising ◽

Immersion Nozzle

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Effect of Slag Layer on Flow Patterns in a Gas Stirred Ladle

Materials Science Forum ◽

10.4028/www.scientific.net/msf.510-511.490 ◽

2006 ◽

Vol 510-511 ◽

pp. 490-493 ◽

Cited By ~ 4

Author(s):

Sung-Ho Cho ◽

Sung Hwan Hong ◽

Jeong Whan Han ◽

Byung Don You

Keyword(s):

Numerical Simulation ◽

Flow Pattern ◽

Model Experiment ◽

Central Area ◽

Side Wall ◽

Slag Layer ◽

Flow Patterns ◽

Water Model ◽

Slag Viscosity ◽

Mixing Behavior

Flow patterns and mixing behaviors in a gas stirred steelmaking ladle with a slag layer were discussed using a water model experiment as well as a numerical simulation. While the water model experiment was performed to investigate the effect of slag on the mixing behavior in ladle, the numerical simulation was carried out to figure out the flow pattern in ladle with a slag layer. Slag viscosity and its thickness in ladle were considered as major variables. It was found that a slag layer made a great change in the flow pattern in ladle, which, in turn, affected on the mixing behavior in ladle. A flow pattern without a slag layer showed that rising bubbles eventually made a recirculation loop at the central area of the ladle and this flow pattern was regarded as a favorable flow pattern for the better mixing behavior. However, a flow pattern with a slag layer showed distorted and localized recirculating loop near side wall below slag layer. This eventually gave a longer mixing time in ladle with a slag layer. Moreover, as the gas flow rate increases, slag existing on top of the ladle was found to be entrained into the melt. Slag viscosity and its thickness were found to be major variables affecting the behavior of slag entrainment. Lower the slag viscosity and thicker the slag layer, much more slag on top of the melt was entrained into the melt.

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Study on Amplitude of the Surface of Liquid Steel in Bottom-Blowing Ladle with Immersed Tube

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.734-737.1511 ◽

2013 ◽

Vol 734-737 ◽

pp. 1511-1515

Author(s):

De Hui Zhang ◽

Ming Gang Shen ◽

Qing Hua Qi ◽

Jin Wei Kuang

Keyword(s):

Flow Rate ◽

Molten Steel ◽

Liquid Steel ◽

Similarity Theory ◽

Steel Slag ◽

Water Model ◽

Argon Flow Rate ◽

Steel Making ◽

Argon Flow ◽

Bottom Blowing

In the process of bottom argon blowing large argon flow rate can cause vigorous fluctuations on the surface of the molten steel and splash and reoxidize the molten steel, making the slag rolled into the steel slag, also causing the erosion of the ladle lining refractories. A 1:7 ratio ladle water model system of 150 ton ladle was established from the similarity theory in the lab. Study and analyze the effects of the inserting depth and diameter of immersed tube and bottom blowing flow rate on the fluctuation of the surface of liquid steel. Results show that the fluctuations on the surface of steel can be limited effectively by changing the diameter and inserted depth of immersed tube when selecting a larger flow rate of bottom blowing, which improve the mixing effect of liquid steel.

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Water Modelling on the Effect of Trapezoidal Nozzle on Vortex during Teeming in Ladle

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.716 ◽

2011 ◽

Vol 295-297 ◽

pp. 716-719

Author(s):

Rui Lin ◽

Zheng Guo Yan ◽

Tao Liu ◽

Jing Kun Yu

Keyword(s):

Cross Section ◽

Late Stage ◽

Model Experiment ◽

Critical Level ◽

Research Work ◽

Water Model ◽

Steel Ladle ◽

Critical Height ◽

Slag Entrapment

Based on approximation principle, water model experiment was carried out during teeming in a 60t steel ladle. Based on the previous research work, trapezoidal nozzlein with lager upper cross section was used to decrease the critical level of vortex in order to reduce the slag entrapment to the tundish. Different shape and height of upper part of the nozzle was investigated mainly to inhibit the vortex at the late stage of ladle teeming. When upper shape of trapezoidal nozzle is square, upper height is 20mm and 17mm, and eccentricity of nozzle is 3/4, critical height of vortex is about 34mm and 31mm. In this case, slag entrapment is controlled effectively and metal utilization is optimized more completely.

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