公开(公告)号：EP1561829A4

公开(公告)日：2007-12-26

申请号：EP03795407

申请日：2003-09-11

申请人： NIPPON STEEL CORP

发明人： ICHIKAWA HIROSHI ,  IBARAKI TETSUHARU ,  IMURA SHOJI ,  ODA HIROSHI ,  ABE YOICHI ,  TAKAHASHI SHIGEKI ,  KANEMORI NOBUYUKI ,  SUZUKI SATOSHI

IPC分类号： C21B13/00 ,  C21B13/10 ,  C22B1/245 ,  C22B5/02 ,  C22B5/10 ,  C22B7/02 ,  C22B13/02 ,  C22B19/30 ,  C22B19/34 ,  C22B1/16 ,  B09B3/00 ,  C02F11/00 ,  C22B1/00

CPC分类号： C21B13/105 ,  C21B13/006 ,  C22B1/245 ,  C22B5/02 ,  C22B5/10 ,  C22B7/02 ,  C22B13/025 ,  C22B19/30 ,  C22B19/34 ,  Y02P10/136 ,  Y02P10/214 ,  Y02P10/216 ,  Y10S75/961

摘要： A method of reduction treatment of metal oxides characterized by using as a material a powder containing metal oxides and containing alkali metals and halogen elements and further, in accordance with need, carbon, mixing said material with water to produce a slurry, then dehydrating this and charging the dehydrated material, mixed with another material in accordance with need, into a rotary hearth type reduction furnace for reduction.

公开(公告)号：EP1439236A4

公开(公告)日：2008-09-03

申请号：EP02708751

申请日：2002-04-01

申请人： NIPPON STEEL CORP

发明人： IBARAKI TETSUHARU ,  YAMAMOTO TAKASHI ,  ABE YOICHI ,  TAKAHASHI SHIGEKI ,  NAGAI KAZUNORI

IPC分类号： C21B13/10 ,  C21B13/00 ,  C22B1/24 ,  C22B1/245 ,  F27B9/16 ,  F27B9/36 ,  F27D19/00 ,  F27D21/00

CPC分类号： F27B9/16 ,  C21B13/0046 ,  C21B13/105 ,  C22B1/24 ,  C22B1/245 ,  F27B9/36 ,  F27D19/00 ,  F27D21/0014 ,  Y02P10/136

摘要： The present invention provides: a method for drying compacts containing water so as not to cause explosion and powdering; a method for reducing the compacts after being dried with great efficiency in a rotary-hearth-type reducing furnace; and a rotary-hearth-type metal reducing furnace. In the present invention, when compacts comprising powder containing metal oxide and carbon are dried, the critical value of a water evaporation rate, beyond which explosion occurs, is determined from the size and porosity of the compacts, then the water evaporation rate is controlled to a value not exceeding the critical value and, by so doing, the increase in the internal pressure of the compacts caused by the generation of water vapor is prevented. By the method, the explosion and cracking of the compacts are prevented. Further, when compacts are dried in a rotary-hearth-type reducing furnace, explosion is prevented by controlling the heat supply rate to the compacts through the above method and successively the compacts are incinerated and reduced in the same furnace.

公开(公告)号：EP1426451A4

公开(公告)日：2008-07-16

申请号：EP02765426

申请日：2002-09-05

申请人： NIPPON STEEL CORP

发明人： IBARAKI TETSUHARU ,  IMURA SHOUJI ,  ODA HIROSHI ,  TAKAHASHI MASAHARU ,  ABE YOICHI ,  TAKAHASHI SHIGEKI ,  SUZUKI SATOSHI

IPC分类号： C22B1/16 ,  C21B13/00 ,  C21B13/02 ,  C21B13/10

CPC分类号： C21B13/105 ,  C21B13/0046 ,  C21B13/023

摘要： A method for producing a reduced iron compact having a high crushing strength, hardly powdering, and having a high reducibility by using a baking reducing furnace of solid reducing type such as a rotary hearth reducing furnace, a reduced iron compact produced by the method, and a method for smelting-reducing the reduced iron compact in a blast furnace. In the method for producing the reduced iron compact, the compact is so produced that the atomic molar ratios of the carbon in a raw powder of a mixture of an iron oxide-containing powder and a carbon-containing powder and the oxygen chemically bonded to iron, manganese, nickel, zinc, and lead or the content of the ferric oxide in the raw powder is in a specific range and that the porosity is in a specific range, and the compact is placed on the hearth of a reducing furnace which the hearth rotates the compact, heated by the heat of the burning gas in the upper part of the furnace, and baked and reduced above a predetermined temperature.