Ferrosilicon reactions play a key role during this process.Since the amount of silicon coming from the recycled metal is usually low, the addition of some ferrosilicon alloy is required in order to achieve the desired composition in the final product. Silicon is usually added into the furnace as ferrosilicon lumps with up to 75 wt% Si. The amount of ferrosilicon added to the cupola accounts for around 1.2–2% of the total metallic charge.