Modelling the Tapping Process in Submerged Arc Furnaces Used in High Silicon Alloys Production

The tapping process is an important step in the silicon and ferrosilicon production process. Tapping is simply how to transfer the melt from the furnace into the ladle. The tapping process has always been a challenging industrial operation where the metal flow rate is influenced by many different phenomena. In this present work we present a model for the tapping of the submerged arc furnaces. Using the model the effects of furnace crater pressure, metal height and permeability of the different internal zones have been studied. The model is based on computational fluid dynamics (CFD) where the geometry is taken from industrial furnace geometry. The internal zones with individual permeabilities are defined based on information from furnace excavations. From the model we extract new information about the process and explain phenomena which control the tapping flow rate. It was found a very good agreement between the model predictions and industrial measurements.