Modelling of ladle glaze interactions

Abstract

model with particular emphasis on the incorporation of ladle glaze, which has been identi ed as a potential source A potential source of inclusions in liquid steel is of inclusions of variable, often undesirable, composition. A ladle glaze, the slag/inclusion coating on the description of pilot plant experiments that were carried out refractory lining of the ladle which is always present to determine the eVect of tapping operations on ladle glaze after casting and before reuse of the ladle. The is given, together with some results of the mathematical composition and quantity of this glaze can vary model incorporating ladle glaze. The implications for the considerably, depending on the range of steel production of clean steel are assessed. qualities being made and, in order to model the effect of glaze on inclusion/top slag formation, a combined fluid flow-thermodynamic model has DESCRIPTION OF MODEL been developed. The behaviour of ladle glaze for Details of the model are described elsewhere. 7 The ladle is various different steels has been studied under pilot divided into 400 'cells' in which the concentrations of all the plant conditions and the results incorporated into dissolved species, elements, and oxides, are known, as well the mathematical model. The implications of the as the temperature and pressure. Important assumptions pilot plant and model results are discussed in the regarding the processes now being modelled include: context of the production of clean steel. I&S/15811. The ferroalloy additions are added to the lling ladle in the same sequence and rate as those used during a plant At the time the work was carried out Dr Hassall, Mr Bain, and trial. They occupy de ned positions depending on density, Dr Warman were with Corus Research, Development and Techwith the elements being released into the liquid steel as a

Chemical Reaction of Glazed Refractory with Al-deoxidized Molten Steel

“…The ladle lining (refractory) in their study was magnesite refractory (carbon-bearing MgO lining). Riaz et al 7) and Hassall et al 8) also performed similar studies on the plant ladle treatment with magnesite refractory. The primary concerns of previous studies were to identify the inclusions and to correlate the melt cleanliness (the number of inclusion) and ladle age.…”

“…The feasibility of the physical detachment can be supported by the microstructure of the glaze layer showing the existence of spinel particles on the interface of glaze and molten steel. Several previous studies [7][8][9][10][11] for the ladle glaze of a magnesite lining also suggested that the particles like MgO originally formed in the glaze layer can be retained in the liquid steel as inclusions. For example, Beskow and Du Sichen 10) reported that the complex inclusion of liquid CaO-Al 2 O 3 (-MgO-SiO 2 ) bearing MgO particles, one of the typical inclusions in a practical ladle treatment, was most probably originated from the ladle glaze itself.…”

“…In particular, refractory materials have been indicated as one of the major sources of non-metallic inclusions in the molten steel during ladle metallurgy. [1][2][3][4][5][6][7][8][9][10][11] Upon the discharge of molten steel into a tundish, the top slag moves down together with the molten steel, causing the molten slag to adhere onto the ladle wall, and freeze when cooled down. This slag film adhered to the ladle refractory is called "ladle glaze".…”

State of the art in the control of inclusions during steel ingot casting

“…[3] Erosion experiments that immersed lining samples into a melt (steel melt [148][149][150][151] or Fig. 29-Effect of teeming rate on the free surface of steel entering a bottom-poured 8-in.…”

“…Lining refractory [89,[148][149][150][151][152][153] Analysis of the lining refractory composition before and after operations can be used to estimate inclusion absorption to the lining and the lining erosion. Also, the origin of a complex oxide inclusion can be traced to lining refractory erosion by matching the mineral and element fractions in the slag with the inclusion composition.…”