Method for rapid reduction of iron oxide in a rotary hearth furnace
AssigneeMidrex International B.V. Rotterdam, Zurich Branch
InventorsDavid C. Meissner, Thomas H. Boyd, James A. Lepinski, Jimmy D. Sloop
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Abstract
A method and apparatus for producing direct reduced iron from dry compacts composed of iron oxide and carbonaceous material by feeding compacts no more than two layers deep onto a hearth and removing all the volatiles and metallizing the compacts by exposing said compacts to a radiant heat source at a temperature of from about 2400.degree. to about 2600.degree. F (1316.degree.-1427.degree. C.) for a total time period of about four to ten minutes and partially cooling the compacts while discharging them from the hearth.
Claims14
A method for producing direct reduced iron from dry compacts composed of iron oxide and carbonaceous material and containing volatile materials therein, comprising:
- feeding said compacts no more than two layers deep onto a hearth;
- removing all of the volatile materials by exposing said compacts to a radiant heat source at a temperature of from about 2400.degree. to about 2600.degree. F. for a first period of time of from one to three minutes and subjecting said compacts to an oxidizing atmosphere with sufficient free oxygen to burn most of the combustible gases evolved from the compacts during said first period of time, and form combusted gases;
- metallizing the compacts by exposing said compacts to a radiant heat source at a temperature of from about 2400.degree. to about 2600.degree. F. in an atmosphere devoid of free oxygen for a second period of time of three to nine minutes;
- and
- causing said gases and said compacts to flow co-currently during said first period of time, and to flow counter-currently for said second period of time, and to form metallized iron product;
- and
- discharging said metallized iron product from the hearth.
Dependencies are inferred from the claim text.