Mathematical Modeling of Furnace Drainage While Tapping Slag and Metal Through a Single Tap-Hole

Furnace tapping is a critical operation on pyrometallurgical furnaces known for
unpredictable performance in many cases. A reduced order mathematical model capable of
predicting tapping rates of both slag and metal is presented. The model accounts for separate
liquid phases and particle bed resistance to flow. The model is compared for consistency against
results from both a water-model experiment and computational fluid dynamics simulations. The
model is applied to study drainage from a typical ferro-manganese furnace. The model results
show that particle bed conditions in the immediate vicinity of the tap-hole strongly influence
tapping rates and that the slag/metal interface deformation due to suction pressure near to the
tap-hole is significant and must be accounted for in such models