Iron oxide reduction with hydrogen

Claim 1

A PROCESS FOR EFFECTING REDUCTION OF IRON OXIDE TO METALLIC IRON, WHICH COMPRISES PASSING HYDROGEN OF AT LEAST 90 PERCENT PURITY THROUGH A BODY OF SAID IRON OXIDE IN FINELY DIVIDED PARTICLE FORM IN AN UNOBSTRUCTED REDUCTION ZONE AT A TEMPERATURE BETWEEN 700 AND 1000* F. AND AT A PRESSURE OF THE ORDER OF HUNDREDS OF POUNDS PER SQUARE INCH GAUGE NOT EXCEEDING ABOUT 600 POUNDS PER SQUARE INCH GAUGE, THE LINEAR VELOCITY OF SAID HYDROGEN THROUGH SAID BODY OF IRON OXIDE PARTICLES BEING SUCH THAT SAID BODY IS MAINTAINED IN A FLUID STATE WITH MINIMUM CARRYOVER OF SOLIDS, WITHDRAWING AN EFFLUENT GAS FROM SAID REDUCTION ZONE, REMOVING WATER FROM SAID EFFLUENT GAS TO SUCH AN EXTENT THAT UPON RECYCLING SAID EFFLUENT GAS TOGETHER WITH FRESH FEED HYDROGEN AS HEREINAFTER RECITED THE COMPOSITE GAS WILL HAVE A MAXIMUM WATER CONTENT NOT EXCEEDING ABOUT 3% BY VOLUME OF THE HYDROGEN CONTENT OF SAID COMPOSITE GAS, RECOMPRESSING SAID EFFLUENT GAS TO A PRESSURE OF AT LEAST 200 POUNDS PER SQUARE INCH GAUGE, MAINTAINING A SUBSTANTIALLY EQUIVALENT PRESSURE WITHIN THE REDUCTION ZONE EXCEPT FOR THE PRESSURE DIFFERENCE NECESSARY TO PRODUCE THE REQUIRED FLOW THROUGH THE SYSTEM, HEATING SAID REPRESSURED EFFLUENT GAS TO A TEMPERATURE ABOVE THAT MAINTAINED IN SAID REDUCTION ZONE, ADDING FRESH FEED HYDROGEN OF AT LEAST 90 PERCENT PURITY TO SAID EFFLUENT GAS IN AN AMOUNT TO FORM SAID COMPOSITE GAS HAVING A RATIO OF SEVERAL VOLUMES OF SAID EFFLUENT GAS TO EACH VOLUME OF SAID FRESH FEED HYDROGEN, PASSING SAID COMPOSITE GAS INTO SAID REDUCTION ZONE TO THEREBY OVERCOME THE TEMPERATURE AND PRESSURE DROPS OCCURRING IN THE REDUCTION AND WATER REMOVAL STEPS AND MAINTAIN SAID TEMPERATURE AND PRESSURE IN SAID REDUCTION ZONE, AND WITHDRAWING A REACTION PRODUCT CONTAINING METALLIC IRON FROM SAID REDUCTION ZONE.