Method for the direct reduction of iron using gas from coal
AssigneeMidrex Corporation
InventorsDavid C. Meissner, Charles W. Sanzenbacher
Life of this patent
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Abstract
A method for direct reduction of iron in a shaft reduction furnace. Spent gas from the furnace is upgraded in reductant by removal of CO.sub.2 and water to form an upgraded gas. A fossil fuel is gasified to produce a hot gas which is tempered with a first stream of upgraded gas. The mixture is desulfurized by reaction with lime to produce hot desulfurized gas. A second stream of upgraded gas is heated and mixed with the hot desulfurized gas to produce hot reducing gas.
Claims6
In a method for reducing iron oxide in a direct reduction furnace wherein hot reducing gas is introduced to said furnace to reduce the iron oxide therein to a metallized iron product and to form a CO.sub.2 containing spent reducing gas, the improvement comprising:
- a. removing a substantial portion of the CO.sub.2 from said spent reducing gas to form a reductant-rich gas;
- b. gasifying fossil fuel to form a hot gasifier gas;
- c. tempering said hot gasifier gas with a first stream of said reductant-rich gas to form a hot gas mixture;
- d. reacting said hot gas mixture with a sulfur acceptor to form a hot desulfurized gas;
- e. heating a second stream of said reductant-rich gas;
- and
- f. mixing said heated second stream of reductant-rich gas with hot desulfurized gas to form a reducing gas having a quality of at least about 8 and a temperature of from about 760.degree. to about 900.degree. C. for introduction to said furnace.
Dependencies are inferred from the claim text.