公开(公告)号：US11293068B2

公开(公告)日：2022-04-05

申请号：US16301272

申请日：2017-05-12

Applicant: Kobe Steel, Ltd.

Inventor： Taiji Hatakeyama ,  Shorin O ,  Masahiro Hotta

IPC: C21B13/00 ,  C21B13/10

Abstract: Disclosed herein is a reduced iron production method enabling heat to be input well into reduced-iron raw materials on a hearth covering material in a reduction-melting furnace to improve the efficiency of treatment thereof. The reduced-iron raw materials are set on the hearth covering material through their falls and reduced on the hearth covering material. The hearth covering material is constituted by carbon materials each having a particle diameter of 5 mm or less. At least 7 mass % of the carbon materials have respective particle diameters each being 0.1 mm or less. This restrains the reduced-iron raw materials from embedment into the hearth covering material.

公开(公告)号：US10571193B2

公开(公告)日：2020-02-25

申请号：US15547864

申请日：2016-01-21

Applicant: Kobe Steel, Ltd.

Inventor： Taiji Hatakeyama ,  Shorin O ,  Tomoki Uemura

IPC: C21B13/10 ,  F27B9/16 ,  F27D3/10 ,  F27B9/10 ,  F27D3/00 ,  F27B9/20 ,  F27B9/38 ,  F27B9/14

Abstract: A method and a device for charging a plurality of reduced iron raw materials into a traveling hearth reduction-melting furnace and treating the raw materials, allowing sufficient input of heat to the reduced iron raw materials on a hearth covering material to improve treatment efficiency are provided. The reduced iron raw materials are released downward from the lower surface of a ceiling of the reduction-melting furnace to be set on a hearth covering material on a hearth and reduced on the hearth covering material. The falling reduced iron raw materials are given a horizontal velocity having a direction equal to the travel direction of the hearth and being greater than the travel speed of the hearth to enable the reduced iron raw materials to roll in the same direction as the travel direction of the hearth after landing on the hearth covering material.

公开(公告)号：US10683562B2

公开(公告)日：2020-06-16

申请号：US15577151

申请日：2016-04-26

Applicant: Kobe Steel, Ltd.

Inventor： Yui Hosono ,  Masaki Shimamoto ,  Takao Harada ,  Shingo Yoshida ,  Shoichi Kikuchi ,  Taiji Hatakeyama

IPC: C22B1/24 ,  C22B1/245 ,  C21B13/00

Abstract: The reduced iron manufacturing method of the present invention includes preparing an agglomerate by agglomerating a mixture containing an iron oxide-containing substance and a carbonaceous reducing agent, and preparing reduced iron by heating the agglomerate to reduce iron oxide in the agglomerate, characterized in that Expression (I) as follows is satisfied: Cfix×Xunder105/OFeO≤51  (I) where OFeO is the mass percentage of oxygen contained in the iron oxide in the agglomerate, Cfix is the mass percentage of total fixed carbon contained in the agglomerate, and Xunder105 is the mass percentage of particles having a particle diameter of 105 μm or less with respect to the total mass of particles configuring the carbonaceous reducing agent.