System for producing carbonized and metallized iron ore pellets

Claim 1

THE PROCESS OF MAKING DISCRETE METALLIZED PELLETS WHICH INCLUDES THE STEPS OF: (A) FORMING A MIXTURE OF FINES OF IRON OXIDE, A CARBONACEOUS MATERIAL, AND A FLUXING MATERIAL, THE CARBONACEOUS MATERIAL CONTAINING CARBON IN AMOUNT SUFFICIENT TO REDUCE 100% OF THE IRON OXIDE TO FREE MAETAL, (B) FORMING MOISTENED PELLETS OF SAID MIXTURE HAVING AND AVERAGE DIAMETER OF ABOUT -1.5, +3/8 INCH, (C) CHARGING SAID MOISTENED PELLETS TO AN ENDLESS CONVEYOR AT A DEPTH OF FROM 3 TO 20 INCHES, TO FORM A BED OF MOIST PELLETS, (D) DRYING SAID BED GASES BY PASSING PREHEATED GASES THERETHROUGH AT A TEMPERATURE OF FROM ABOUT 300* F. TO ABOUT 600*F., (E) HEATING SAID BED BY PASSING OXIDIZING GAS THERETHROUGH TO RAISE THE TEMPERATURE OF SAID BED TO BETWEEN 1000*F. AND 2000*F., AND (F) SUBSEQUENTLY HEAT SOAKING AND METALLIZING SAID BED BY PASSING NON-REACTIVE GASES CONTAINING NOT MORE THAN 5% OF OXYGEN BY WEIGHT, THROUGH THE BURDEN TO RAISE ITS TEMPERTURE TO A MAXIMUM OF ABOUT 2400* F. FOR A PERIOD OF TIME SUFFICIENT TO REDUCE FROM 60% TO NO MORE THAN ABOUT 90% OF THE CHEMICALLY COMBINDED IRON IN SAID MIXTURE TO METALIC IRON.