Nkk Corporation

Shinichi Isozaki

Genji Kanatani

Masayuki Watanabe

Tatsuro Ariyama

Haruhito Tsuboi

Masahiro Matsuo

Hitoshi Kawata

Yoshiyuki Kitano

Noboru Sato

Takeshi Sekiguchi

Noboru Sakamoto

Katsuhiro Iwasaki

Masahiro Kawakami

Kenzo Yamada

Yoshihito Iwata

Jirou Mase

Terutoshi Sawada

Sakae Arakawa

Jiro Mase

Junichi Fukumi

Tatsurou Ariyama

A smelting reduction method comprising (a) charging a carbonaceous material and an ore into a reacting furnace to directly contact the carbonaceous material and the ore; (b) reducing the ore until at least a part of the ore is metallized, the resultant reduced ore containing at least a part of metallized metal being produced; (c) charging the carbonaceous material and the ore containing at least a part of the metallized metal from step (b) into a smelting furnace having a metal bath; and (d) blowing a gas containing 20% or more of oxygen into the metal bath in the smelting furnace to produce molten iron.

Smelting reduction method

A method for recovering zinc oxide comprises the steps of: agglomerating a dust; charging the agglomerate to a molten iron in a melting furnace; collecting a dust generated from the melting furnace; recycling a part of the collected dust and recovering another part of the collected dust. An apparatus for recovering zinc oxide comprises: an agglomeration unit for agglomerating a dust containing iron oxide and zinc oxide; a melting furnace for accepting the agglomerate and for holding the molten iron for reducing the dust; and at least two units of dust collector for collecting the dust containing zinc oxide generated from the melting furnace.

Method for recovering zinc oxide from dust

Apparatus for recovering zinc oxide from dust

A method for controlling a flow rate of gas for prereducing ore comprises the steps of prereducing ore in a prereduction furnace having a fluidized bed with a gas generated in a smelting reduction furnace and controlling a pressure of gas generated in the smelting reduction furnace and introduced into the prereduction furnace, thereby controlling the actual flow rate of gas introduced into the prereduction furnace. An apparatus for controlling a flow rate of gas for prereducing ore comprises a flow passage for introducing gas generated in a smelting reduction furnace into a prereduction furnace and a gas pressure control valve positioned in the flow passage.

Method for controlling a flow rate of gas for prereducing ore and

A prereduction furnace of a smelting reduction facility of iron ore includes of a fluidizing prereduction chamber at an upper part of the prereduction furnace wherein iron ores are fed and prereduced, a gas blowing chamber at a lower part of the prereduction furnace wherein a reducing gas is fed, a ceramic main body of a distributor mounted between the fluidizing prereduction chamber and the gas blowing chamber, a metal box attached to the bottom side of the ceramic main body, which prevent adhesion of dust in the reducing gas, nozzles passing through the ceramic main body and through the metal box for injecting the reducing gas in the blowing chamber, into the prereduction chamber and a discharge pipe for discharging prereduced iron ores mounted at a bottom center portion of the prereduction chamber and extending through the ceramic main body, through the metal box, and through a bottom of the gas blowing chamber.

Prereduction furnace of a smelting reduction facility of iron ore

A prereduction furnace of a smelting reduction facility comprises a fluidizing prereduction chamber in the upper part of the prereduction furnace wherein iron ores are fed and prereduced, a gas blowing chamber installed in the lower part of the prereduction furnace wherein a reducing gas is fed, a distributor for separating the fluidizing prereduction chamber from the gas blowing chamber, and a discharge pipe for discharging the prereduced ore from the fluidizing prereduction chamber. The distributor includes a body of refractory material, a metal plate installed on the bottom of the body, nozzles passing through the body and the metal plate, metallic pipes inserted in the nozzles, and cooling pipes connected to the metal plate. A metallic box may be installed below the metal plate for providing passages for gas flow. A bottom plate may be installed spacedly below the metal plate, with nozzles passing therethrough. The distributor may comprise a rigid thick plate and a refractory layer thereon.

Growing community of inventors

Yokohama, Japan

Shinichi Isozaki