Method for operating moving hearth reducing furnace
AssigneeKabushiki Kaisha Kobe Sieko Sho (Kobe Steel, Ltd.)
InventorsMasataka Tateishi, Koichi Matsushita, Hidetoshi Tanaka, Takao Harada
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Abstract
A moving hearth reducing furnace is operated, while a gap is provided between a discharging apparatus for discharging reduced iron agglomerates from the moving hearth reducing furnace and the surface of the moving hearth. The gap prevents squeezing metallic iron powder formed by reduction of powder included in iron oxide agglomerates into the surface of the moving hearth and the formation of an iron sheet. An iron oxide layer formed on the moving hearth during the operation can be periodically scraped off without shutdown of the furnace.
Claims12
A method for operating a moving hearth reducing furnace, the method comprising:
- feeding iron oxide agglomerates incorporated with a carbonaceous material onto a moving hearth of a moving hearth reducing furnace;
- reducing the iron oxide agglomerates to form reduced iron;
- and
- providing a gap between a discharging apparatus for discharging the reduced iron from the moving hearth reducing furnace and the surface of the moving hearth,
- the discharging apparatus is raised continuously or intermittently from the surface of the moving hearth in response to the thickness of an iron oxide layer formed on the moving hearth by oxidation of iron oxide powder included in the iron oxide agglomerates.
A method for operating a moving hearth reducing furnace, the method comprising
- feeding iron oxide agglomerates incorporated with a carbonaceous material onto a moving hearth of a moving hearth reducing furnace;
- reducing the iron oxide agglomerates to form reduced iron;
- and
- providing a gap between a discharging apparatus for discharging the reduced iron from the moving hearth reducing furnace and the surface of the moving hearth, wherein
- iron oxide powder included in the iron oxide agglomerates, metallic iron powder formed by reduction of the iron oxide powder, and metallic iron powder formed when the reduced iron is discharged from the furnace are evacuated together with exhaust gas through a duct provided in the vicinity of the discharging apparatus and a feeder for feeding the iron oxide agglomerates.
A method for operating a moving hearth reducing furnace, the method comprising:
- feeding iron oxide agglomerates incorporated with a carbonaceous material onto a moving hearth of a moving hearth reducing furnace;
- reducing the iron oxide agglomerates to form reduced iron;
- and
- providing a gap between a discharging apparatus for discharging the reduced iron from the moving hearth reducing furnace and the surface of the moving hearth, wherein
- the discharging apparatus is an electromagnet unit which reciprocally moves in the radial direction of the moving hearth reducing furnace, and which attracts and discharges simultaneously the reduced iron and the metallic iron powder from the moving hearth reducing furnace.
A method for operating a moving hearth reducing furnace, the method comprising:
- feeding iron oxide agglomerates incorporated with a carbonaceous material onto a moving hearth of a moving hearth reducing furnace;
- reducing the iron oxide agglomerates to form reduced iron;
- providing a gap between a vertically movable discharging apparatus and the surface of the moving hearth;
- and
- adjusting the gap with the discharging apparatus, wherein
- the vertically movable discharging apparatus is for discharging the reduced iron from the moving hearth reducing furnace.
Dependencies are inferred from the claim text.