A 2D Numerical Modeling Study of Slag Splashing in a Basic Oxygen Steelmaking Furnace

Abstract

Wearing of the inner refractory lining in a basic oxygen steelmaking (BOS) furnace occurs due to the harsh operating conditions, which reduces the useful life of the refractories and incurs a significant cost component for relining. The lifespan can be prolonged by forming a protective coating layer on the refractory walls by using the retained slag splashing technique. In this study, an Eulerian-Eulerian multiphase computational fluid dynamics (CFD) model was developed to (i) identify the potential wear-prone zones in an industrial-scale BOS system during the supersonic oxygen blowing phase by quantifying the wall shear stress distributions and (ii) simulate the retained slag splashing process by introducing an inert gas to the retained slag mass to achieve a protective coating on the refractory walls. Two distinct lance head configurations comprising six nozzles and five nozzles were used to predict the potential wear-prone zones. Both the lance head designs and lance positions were found to influence the coating area. An increase in the retained slag volume was noted to augment the coating area substantially. An optimal lance position was identified within the physical constraints, wherein the maximum coated area was achieved for all operating conditions. The bottom bubbling process through the tuyeres on the furnace floor was also found to affect the wall coating performance.