Method and apparatus for manufacturing sponge iron

A method of manufacturing sponge iron by the continuous reduction of iron oxides in a shaft furnace comprising the steps of:

• (1) removing the reaction gas from a shaft furnace;
• (2) removing from said reaction gas substantially all CO.sub.2 and H.sub.2 O;
• (3) dividing the reaction gas into at least two flow portions;
• (4) passing one of said flow portions to a gas generator comprising a gas generating shaft substantially filled with a solid reducing agent, a plasma burner arranged in the lower portion of said shaft, and means for injecting oxidant, and heating said reaction gas by said plasma burner and injecting into the heated gas from the plasma burner an oxidant so as to form an intermediate gas mixture comprised primarily of CO and H.sub.2 ;
• (5) maintaining said intermediate gas mixture at a temperature such that ash contained within the solid reducing agent forms a slag;
• (6) mixing said intermediate gas with at least one of said other flow portions in such proportion that the temperature of the resulting reduction gas is suitable for the reduction of iron oxides in a shaft furnace;
• (7) injecting said reduction gas into the lower portion of a shaft furnace and passing said reduction gas upwardly through said shaft furnace so as to reduce iron oxides contained in said furnace;
• and
• (8) removing from said furnace the reduced iron.