Rotary hearth furnace for reducing oxides, and method of operating the furnace
AssigneeKawasaki Steel Corporation
InventorsKanji Takeda, Yoshitaka Sawa, Tetsuya Yamamoto, Tetsuya Kikui
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Abstract
Traveling hearth furnace and an operating method thereof, which, when stacking a layer consisting of a mixture of oxides such as fine iron ore and a fine solid reducing material onto a horizontally traveling hearth and reducing the oxides through radiant heat transfer from above the hearth, is based on melting the reduction product in the course of up to a discharge port, and causing aggregation and separation of slag in from the reduction product, followed by solidifying the reducible material.
Claims13
A method of operating a traveling hearth furnace, comprising:
- stacking a layer comprising a mixture of fine iron ore and a fine solid reducing material onto a hearth traveling horizontally therewith while transferring said layer along a course in said furnace,
- subjecting said layer to a reduction reaction via radiant heat transfer from the upper portion of the hearth,
- melting reduced iron from said reduction reaction,
- subjecting said reduced iron to separation of slag from said reduced iron by melting said reduced iron to reduce viscosity of said slag, causing separation of said slag from said reduced iron by aggregation and displacement, thus converting said reduced iron into separate bodies comprising said reduced iron and said slag,
- solidifying said reduced iron, and
- discharging said reduced iron from the furnace.
A traveling hearth furnace, comprising:
- a hearth for conducting preheating and reduction of a layer comprising a mixture of fine iron ore and a fine solid reducing material stacked thereon while transferring said layer along a course in said furnace, and a furnace body surrounding said hearth and provided with one or more burners at the top of the inside thereof;
- wherein said hearth furnace has a distinct melting zone comprising physical partitioning to create a melting chamber separate from a preheating zone and a reduction zone, wherein said physical partitioning allows free movement of said hearth, and wherein a reduced iron is melted in said melting chamber to provide means to separate therefrom slag contained therein by reducing viscosity of said slag, and means for causing separation of said slag from said reduced iron by aggregation and displacement, and the product is led to a discharge port for discharging said product.
Dependencies are inferred from the claim text.