Patent ID: 6749661
Filing Date: 2004-06-15
Classification: C21C,F27B,F27D,H05B,Y02P

Abstract:
A method of melting metal and decarburizing an iron carbon melt with one or more injection apparatus in an electric arc furnace having a side wall and a refractory with a hot face for holding the iron carbon melt up to a sill line, comprising the steps of:forming a reaction zone in the iron carbon melt; injecting with at least one the injection apparatus a flow of combustion gas toward said reaction zone; directing said combustion gas flow from an injection point at an injection angle such that the combustion gas flow travels along a diagonal path from the injection point to the iron carbon melt; directing said combustion gas flow from the injection point at an injection distance such that the distance along said diagonal path from the injection point to the iron carbon melt is less than the distance along a colinear diagonal path from the side wall of the furnace to the iron carbon melt; melting metal with said combustion gas flow along said diagonal path; injecting with at least one of the injection apparatus a flow of oxidizing gas with a velocity high enough to decarburize the melt toward said reaction zone after the metal has been partly melted and an iron carbon melt has formed in said reaction zone; directing said oxidizing gas flow from an injection point at an injection angle such that the oxidizing gas flow travels along a diagonal path from the injection point to the iron carbon melt; directing said oxidizing gas flow from the injection point at an injection distance such that the distance along said diagonal path from the injection point to the iron carbon melt is less than the distance along a colinear diagonal path from the side wall of the furnace to the iron carbon melt; and such that said injection distance is less than 65â€³ and said injection point is less than 24â€³ vertically above the sill line of the furnace.