Refining of metals

Abstract

This invention uses a dual basicity (DB) flux during the refining of steel which comprises the use of one or more flux components with high basicity/activity, for example sodium carbonate and/or barium oxide, with one or more normal fluxes having a lower basicity/activity such as calcium or magnesium oxides or dolomite. It has been found that it is only necessary to use a small percentage of the said high basicity fluxes in the total flux, for example 10%. The use of the said DB type of flux is particularly apt when the total amount of flux used is reduced to give a slag with a low Vee Ratio (CaO:SiO.sub.2), of the order of 1.0 to 2.0, and when magnesia is present in the slag formed preferably derived from an added lower basicity (MgO) flux component or partly from the furnace refractory lining.

Dependencies are inferred from the claim text.