Method for reducing particulate iron oxide to molten iron with solid reductant and oxy-fuel burners
AssigneeMidrex Corporation
InventorsDonald Beggs, Bruce G. Kelly, David C. Meissner
Life of this patent
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Abstract
A method and apparatus for reducing particulate iron oxide to molten iron utilizing solid carbonaceous fuel as reductant in a shaft type reducing furnace, in which a furnace burden is formed of a mixture of iron oxide lumps or pellets and particulate solid fuel. Reacted top gas is upgraded and recirculated through the burden in counterflow relationship thereby heating and reducing the burden. The heat for reduction is generated by passing electric current through the burden. A portion of the heat for melting of reduced iron and a supplemental source of hot reducing gas is provided by oxy-fuel burners located in the shaft furnace above the molten iron pool.
Claims6
A method for reducing particulate iron oxide to molten iron with a solid reductant, comprising
- a. continuously feeding a charge of particulate iron oxide and solid particulate carbonaceous fuel to a particle inlet at the top of a shaft furnace to establish a packed bed burden therein leaving a stockline at the top thereof;
- b. passing an electric current through the burden to provide sufficient heat by electric resistant heating to react said carbonaceous fuel with oxygen from said particulate iron oxide to reduce said iron oxide substantially to metallic iron and to melt the iron and form a molten iron pool in the bottom of said furnace;
- c. heating the lower portion of said burden above said molten metal pool with an oxy-fuel burner;
- d. causing the reaction products to move through said particulate burden in counterflow relation therewith and form a top gas;
- e. removing said top gas from the upper region of the shaft furnace;
- f. cooling the top gas;
- g. recirculating the cooled top gas to the burden through a gas inlet at the lower region of said furnace above the elevation of the oxy-fuel burners;
- h. removing molten iron product and slag from the bottom of said furnace.
Dependencies are inferred from the claim text.