Study of inclusion removal mechanism around open eye in ladle treatment

Abstract

In the present study, the inclusion removal mechanism by rising bubbles around the open eye in a gas stirred ladle was investigated using a cold model. Water and silicone oils were employed to simulate liquid metal and slag respectively. Both fine silicone oil droplets and charcoal particles were used to simulate inclusions. Around the open eye, the oil layer exhibited a sphere bed structure when a critical gas flowrate was reached. The sphere bed was composed of many oil droplets, each of which was coated with a thin water film. The injected inclusions mostly followed the stream of water flow and were brought up to the open eye by the gas-water plume. A fraction of the inclusions were captured by the sphere bed when passing through the openings between the oil droplets, while the rest of the inclusions came back to the water bath and joined the stream of the flow again. The sphere bed was found to function as a filter to the tiny particles or oil droplets. On the basis of this mechanism, a preliminary comparison of the contribution of inclusion removal by metal-gas plume in the open eye region with the contribution of buoyancy was made.

“Vacuum Shroud (VS)”-A Green Flow Control Device (FCD) towards Replacement of “Turbo Stop” In Tundish Metallurgy

“…One of the literatures embodied a practical image of slag eye where four zones are observed like bare metal, thin slag, fluid slag and crusty slag [51]. The thin and fluidic slag layer near the open eye region captured very little amount inclusions particles which is also proof by physical model investigation of the some researchers [52]. Although the total oxygen generally measure near the stopper rods of the tundish but it is observed by some metallurgists that inclusions mainly concentrated at the region if slag eye of the tundish during steady state and unsteady state conditions [53].…”

Effect of Inert Gas Flow Rate on Homogenization and Inclusion Removal in a Gas Stirred Ladle

“…However, many inclusions are found to follow the metal flow coming out from the open‐eye region without being separated to the slag 20. Chevrier and Cramb 21 report that even the inclusions having the size larger than 1 mm would stay at the slag‐metal interface for about 11 s before entering the slag.…”

A Numerical Study about the Influence of a Bubble Wake Flow on the Removal of Inclusions

“…15) The removal of inclusions by gas injection may be the result of bubble adhesion or bubble wake capture. 16,17) The attachment of particles on the rising bubbles has been the focus in most investigations. However, few numerical studies have been done to study the influence of the bubble wake flow on the removal of inclusions during steelmaking.…”

“…However, few numerical studies have been done to study the influence of the bubble wake flow on the removal of inclusions during steelmaking. 17) In this study, a gas bubbling water model has been built and it has been used to study the interaction between a bubble and a particle. Then a coupled VOF and DPM models was applied to investigate the single bubble-liquidparticle system.…”