Jfe Steel Corporation

Natsuo Ishiwata

Yoshitaka Sawa

Tetsuya Yamamoto

Kanji Takeda

Tatsuya Ozawa

Tetsuya Kikui

Yuki Okamoto

Yusuke Kashihara

Atsushi Sakai

Koichi Nushiro

Kazuhira Ichikawa

Yohei Kitamura

Yasukazu Hayasaka

Hiroyuki Hiroha

A blast furnace operation method comprising a blast furnace to start up smoothly and perform operation after suspending air blowing by removing as much as possible residual coke that remains inside the furnace during suspension of air blowing and becomes an obstacle to discharging solidified matter. In this blast furnace operation method, air blowing is suspended with the height of a surface of a raw material-filled layer immediately above a blast-furnace tuyere reduced below the height of an upper end of a blast-furnace bosh and then air blowing is resumed. After air blowing into the blast furnace is suspended, oxygen or oxygen and a combustible gas are blown in through a burner inserted into a taphole to combust coke remaining inside the furnace and reduce the volume of residues inside the furnace, and after new coke is charged to a region where the volume decreased, air is blown through a tuyere.

Blast furnace operation method

Disclosed is a blast furnace apparatus includes: a rotating chute; a profile measurement device configured to measure surface profiles of a burden charged into the furnace; and a tilt angle controller configured to control a tilt angle of the chute, in which the device includes a radio wave distance meter installed on the furnace top and configured to measure the distance to the surface of the burden, derives the profiles on a basis of distance data for the entire furnace obtained by scanning a detection wave of the distance meter in the furnace in a circumferential direction, and includes at least one of arithmetic units configured to command during rotation, on a basis of the surface profiles obtained, the controller to change the tilt angle of the chute, or a controller to change a rotational speed of the chute or a feed speed of the burden fed to the chute.

Blast furnace apparatus and operation method for blast furnace

Disclosed is a blast furnace apparatus includes: a rotating chute; a plurality of tuyeres; a profile measurement device configured to measure surface profiles of a burden charged into the blast furnace through the rotating chute; and a blowing amount controller configured to control a blowing amount of at least one of hot blast or pulverized coal in each of the plurality of tuyeres, in which the profile measurement device includes: a radio wave distance meter installed on the blast furnace top and configured to measure the distance to the surface of the burden charged; and an arithmetic unit configured to derive the surface profiles of the burden on a basis of distance data for the entire blast furnace related to distances to the surface of the burden obtained by scanning a detection wave of the radio wave distance meter in the blast furnace in a circumferential direction.

In a method for producing pig iron using iron ore with a high content of zinc, a blast furnace raw materialis produced using iron ore with a high content of zinc which contains 0.01 mass % or more of zinc and 50 mass % or more of iron, pig iron is produced by charging the blast furnace raw materialinto a blast furnaceand, at the same time, zinc-containing dustin a blast furnace discharge gas is recovered, and zincis recovered from the zinc-containing dustusing a reduction furnace. A mixed raw material into which the zinc-containing dust, a carbonaceous solid reducing material and a slag-making material are mixed is preferably charged on a movable hearth, and the mixed raw material is preferably reduced by supplying heat from an upper portion of the movable hearth so as to recover zincwhile producing reduced iron

Method for producing pig iron

A method for discharging a reduced product produced on a movable hearth of a movable-hearth furnace uses a discharging device. The discharging device includes a removal unit for removing the reduced product from the movable hearth, a separation unit for separating the reduced product from a solid reductant, a leaving-returning unit for either leaving substances other than the reduced product on a solid reductant layer or returning the substances onto the solid reductant layer, and a discharge unit for discharging the reduced product to the outside of the movable-hearth furnace.

Growing community of inventors

Chiba, Japan

Natsuo Ishiwata