Method of reducing iron oxide to sponge iron

Claim 1

A CONTINUOUS PROCESS FOR THE REDUCTION OF IRON OXIDE TO IRON IN SPONGEMETAL FORM WHICH COMPRISES FORMING ORE COMPRISING IRON OXIDE INTO SUBSTANTIALLY ROUND PELLETS, HEATING SAID PELLETS UNDER OXIDIZING CONDITIONS UNTIL THE SAME ARE SUBSTANTIALLY FULLY OXIDIZED, WHEREBY SULFUR IS REMOVED THEREFROM AND SAID PELLETS ARE CHANGED INTO A HARD, POROUS CRYSTALLINE STATE, MIXING THEREWITH A REDUCING AGENT IN FINELY DIVIDED FORM COMPRISING LIMESTONE AND A SOLID CARBONACEOUS MATERIAL CAPABLE OF REDUCING CARBON DIOXIDE TO CARBON MONOXIDE, SAID LIMESTONE AND ITS SOLID DECOMPOSITION PRODUCT SERVING AS AN INTEFERRING PHASE BETWEEN SAID PELLETS DURING REDUCTION, THE QUANITY OF CARBONACEOUS MATERIAL IN SAID REDUCING AGENT BEING AT LEAST SUFFICIENT TO REDUCE ALL OF THE CARBON DIOXIDE LIBERATED BY DECOMPOSITION OF SAID LIMESTONE AS WELL AS THAT EVOLVED IN THE IRON OXIDE REDUCTION TO CARBON MONOXIDE, PROVIDING A REDUCING ZONE, CHARGING SAID MIXTURE OF IRON OXIDE PELLETS AND REDUCING AGENT TO SAID ZONE AND PROVIDING A BED OF SAID MIXTURE THEREIN, DIRECTLY HEATING SAID MIXTURE WITHIN SAID ZONE WITH AN AXIDIZING CONDITION AT ITS CHARGING END TO A TEMPERATURE SUFFICIENT TO DECOMPOSE SAID LIMESTONE LIME AND CARBON DIOXIDE, WHEREBY AT SAID TEMPERATURE SAID CARBON DIOXIDE IS REDUCED WITHIN THE BED