Thermal modeling of air gaps on the cooling capacity of finger coolers in an electric smelting furnace

While water cooling systems are used to freeze a slag layer on the refracto ry sidewall to prevent refractory erosion by the molten slag, it should not remove excessive thermal energy from the electric smelting furnace. One an d three-dimensional thermal mathematical models are used to examine conditi ons where a solid slag layer will form on the refractory. The effect and se nsitivity of an air gap between the copper cooling finger and the refractor y is examined from the slag solidification perspective. Will a protective s lag solidify on the refractory? Other issues examined include copper finger tip temperature, number of fingers per unit transverse area versus larger fingers, location of finger tip into the furnace wall and from the slag int erface (depth of penetration) and maximum operating sidewall heat flux q(ma x) where no protective slag layer is formed. These are important factors th at affect cooling finger placement in the electric smelting furnace. A 1 mm air gap can potentially decrease the water cooling capacity by 30%.