Study of dynamic refractory wear by slags containing very high FeO contents under steelmaking conditions

Abstract

The wear of industrial refractory materials was studied in contact with slag containing high amounts of FeO using the rotating finger technique. The thermodynamic equilibrium of the refractory slag systems was also determined in Thermo-calc ® and FactSage™. The studied refractories were alumina spinel, zirconia, graphite, silicon carbide (SiC), magnesia-carbon (MgO-C), chromite (Cr2O3), and MgO-Spinel (MgO-Al 2 O 3). The fingers were rotated in a FeO x (90wt%)-SiO 2 (5wt%)-CaO (5wt%) slag for 3 hours in a molybdenum crucible at 100 RPM at 1700K. The wear of the refractory fingers was determined by dimensional changes and changes in composition of the slags. Only MgO-spinel refractories exhibited resistance to the slag. The thermodynamic equilibrium calculations were able to predict the experimental behavior when appropriate databases were used, with the exception of the chromite slag.

Possible ecological advantages from use of carbonless magnesia refractory bricks in secondary steelmaking: a framework LCA perspective

“…According to Ewais (2004), in a ladle with the capacity of 90 t of molten steel, the replacement of fireclay bricks (33% of Al 2 O 3 ) with high-quality 65% Al 2 O 3 bricks enhanced the ladle life to 45 heats, whereas MgO-C bricks are characterized by better performances. The thermo-mechanical properties of several carbonless refractory recipes developed in the course of the project, till the latest presented in this paper, have been studied extensively in controlled laboratory tests conditions (Wang et al 2015;Wang and Sichen 2016;Wang et al 2017;Svantesson et al 2020). In particular, in the latter reference, MgO-spinel-type refractories (87 wt% MgO -9 wt% Al 2 O 3 and 81 wt% MgO -16 wt% Al 2 O 3 ) showed the most resistance toward the studied type of slag and deserve further research.…”

Analysis of fluid flow characteristics of RH reactor with different bottom-blowing arrangements

“…After increasing bottom-blowing, on the one hand, the turbulence in the ladle is intensified, on the other hand, when bubbles enter the up-snorkel or flow to the gap between the up-snorkel and the ladle wall, they will drive the movement of molten steel and slag. The relative movement between high-speed molten steel and refractory caused shear stress, causing mechanical scouring to refractory, and the surface of refractory was constantly torn and peeled off [14,38].…”

“…Overall, the best bottom-blowing position is 0.2 and the included angle is /4, but there is little difference with the included angle of 0. In addition, it also should be noted that due to the expansion of bubbles at high temperature during bottom-blowing, the violent movement of molten steel will also be caused under a small flow rate, and the wall shear stress will increase, which is easy to aggravate erosion [17,29,36–38]. Attention must be given to the influence of the selection of bottom-blowing position on the service life of refractory materials.…”