Research Institute of Industrial Science & Technology

Voest-alpine Industrieanlagenbau Gmbh

Pohang Iron & Steel Co. Ltd.

Other

Il Ock Lee

Uoo Chang Chung

Yong Ha Kim

Werner L. Kepplinger

Hang Goo Kim

Felix Wallner

Johannes L. Schenk

Bong Jin Jung

Werner Leopold Kepplinger

Sang Hoon Joo

Johannes Leopold Schenk

Franz Hauzenberger

Min Young Cho

Uoo Chang Jung

Nag Joon Choi

Sang Deok Lee

Suk In Park

Dae Gyu Park

Werner L Kepplinger

A two-stage fluidized bed reducing apparatus and a reducing method for fine iron ore of a wide particle size distribution with an increased degree of utilization of the reducing gas. Fine iron particles dropping through the holes of a gas distributor can be recycled into the fluidized bed furnace, thereby preventing an impediment of the reducing gas flow due to abnormal defluidizing or channeling. A first fluidized bed furnace dries, pre-heats and pre-reduces the fine iron ore, and a second fluidized bed furnace finally reduces the pre-reduced iron ore. Downstream of the respective fluidized beds are installed intermediate hoppers and gas/solid sealing valves. Thus, the fine iron ore particles which drop through the holes of gas distributors during the abnormal operation are recycled to the furnaces. Accordingly, the gas flow is not impeded.

2-stage fluidized bed type fine iron ore reducing apparatus, and reducing method using the apparatus

A fluidized bed reducing system for reducing a fine iron ore is disclosed, in which the structure of the fluidized bed reducing furnace is improved such that the coarse iron ore particles are distributed in the lower portion of the fluidized bed within the furnace and the fine iron ore particles are distributed in the upper portion of the fluidized bed. Thus, the average residence times of the particles in the furnace are adjusted differently for different ore sizes, so that the reducing efficiency can be improved, and that the residence time of the reducing gas in the furnace can be extended, thereby improving the degree of gas utilization. The fluidized bed reducing system for reducing a fine iron ore includes: an upper iron ore outlet for discharging fine iron ore particles; a lower iron ore outlet for discharging coarse iron ore particles; a gas distributor installed in a lower portion of a reducing furnace; a gas inlet formed on a lower portion of the reducing furnace for introducing a reducing gas; an iron ore inlet for supplying an iron ore of wide particle size distribution; a circulating duct connected to an upper portion of the reducing furnace for discharging extremely fine iron ore particles together with the reducing gas; a particle capturing device an extremely fine iron ore recycling duct. The fluidized bed reducing furnace includes a cylindrical upper portion and a tapered lower portion, the tapered portion being in a wide-upper-narrow-lower shape.

Growing community of inventors

Pohang, South Korea

Il Ock Lee