Fluid Flow Turbulence in the Proximities of the Metal-Slag Interface in Ladle Stirring Operations

Abstract

Three-phase interactions (metal-slag-argon) in ladle stirring operations have strong effects on the metal-slag mass transfer processes. Specifically, the thickness of the slag controls the fluid turbulence to an extent that once trespassing a critical thickness, increases of stirring strength no longer effect the flow. To analyze these conditions, a physical model considering the three phases was built to study liquid turbulence in the proximities of the metal-slag interface. A velocity probe placed close to the interface permitted the continuous monitoring and statistical analyses of any turbulence. The slag eye opening was found to be strongly dependent on the stirring conditions, and the mixing times decreased with thin slag thicknesses. Slag entrainment was enhanced with thick slag layers and high flow rates of the gas phase. A multiphase model was developed to simulate these results and was found to be a good agreement between experimental and numerical results.

Refining and Casting of Steel

“…Slag entrainment was enhanced with thick slag layers and high flow rates of the gas phase. A multiphase model was developed to simulate these results and was found to be a good agreement between experimental and numerical results [3].…”

“…The papers covered by this Special Issue are state-of-the-art in the fields of crucial multiphase interactions in the steel making furnaces: basic oxygen furnace (BOF) [1] and electric arc furnace (EAF) [2]. Next, the research focuses on the matters related to the secondary refining processes; fluid's turbulences with nearby metal-slag interface in the ladles [3], the evolution of inclusions for Ti-bearing steels treated by calcium [4], and an influence of aluminum on flux flow in the ladle during Ruhrstahl Heraeus (RH) degassing operations [5]. Other papers are devoted to a geometry of impact area in the tundish [6], cleanliness consequences of an intermixing of the different steel grades in the tundish [7], and the reoxidation of steel from tundish cover flux [8].…”

“…The kinetics of interaction at the metal-slag interface and also the possibility of a slag entrapment are strongly influenced by the character of fluid flow in the ladle. Three-phase interactions (metal-slag-argon) in ladle stirring operations have strong effects on the metal-slag mass transfer processes, Calderón-Hurtado et al [3]. Specifically, the thickness of the slag controls the fluid turbulence to an extent that, once trespassing a critical thickness, increases of stirring strength no longer affects the flow.…”

Process optimization of bottom-blown argon for 130t ladle furnace

“…Most studies of ladle bottom-blowing argon have focused on the effect of various process conditions on mixing time and slag eye formation [15]. Feng [16], nozzle diameter [17], tracer addition location [18], electromagnetic stirring [19], fluid-dynamic structure [20], and different purging plug designs [21] [6], slag layer thickness [22], fluid flow turbulence [23], and physical parameters of slag (density, viscosity) [24,25] on open eye formation, respectively. Tang et al [26] and Villela-Aguilar et al [27] proposed a new blowing mode with different flow rates designed for each plugs, which can reduce the mixing time and open eye area with the same blowing flow rate.…”

“…Feng et al, Terrazas et al, Herrera-Ortega et al, Sand et al, González-Bernal et al, and Tan et al investigated the effects of nozzle radius position [16], nozzle diameter [17], tracer addition location [18], electromagnetic stirring [19], fluid-dynamic structure [20], and different purging plug designs [21] on mixing time, respectively. Ramasetti et al, Morales et al, Calderón-Hurtado et al, and Amaro-Villeda et al investigated the effects of argon gas flow rate [6], slag layer thickness [22], fluid flow turbulence [23], and physical parameters of slag (density, viscosity) [24,25] on open eye formation, respectively. Tang et al [26] and Villela-Aguilar et al [27] proposed a new blowing mode with different flow rates designed for each plugs, which can reduce the mixing time and open eye area with the same blowing flow rate.…”