Patents by Inventor Kiminori Hajika

Kiminori Hajika has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8506880
    Abstract: An iron melting furnace has a refractory lined furnace body having a top opening through which raw materials including a raw material iron source, a carbonaceous material and a slag forming material may be introduced. A heating system is provided for injecting oxygen-containing gas into the furnace body to combust the carbonaceous material, whereby combustion heat can melt the raw material iron source to generate molten iron and molten slag to form a molten iron and slag bath. A plurality of tap holes penetrate the furnace body and are provided at positions different from one another in a height direction of the furnace body, and a refractory filling which is different from the refractory liner material fills at least one of the tap holes such that molten iron or slag in the furnace is unable to flow through the tap hole being filled with the refractory material.
    Type: Grant
    Filed: August 6, 2009
    Date of Patent: August 13, 2013
    Assignee: Kobe Steel, Ltd.
    Inventors: Hideaki Fujimoto, Korehito Kadoguchi, Kiminori Hajika, Hiroshi Sugitatsu
  • Patent number: 8277536
    Abstract: A process for producing molten iron with a combination of a moving-hearth reducing furnace and an iron bath-type melting furnace that includes charging a bedding carbonaceous material on a hearth of the moving-hearth reducing furnace and placing carbonaceous material-containing agglomerates containing a powdery iron oxide source and a powdery carbonaceous reductant on the bedding carbonaceous material; thermally reducing the carbonaceous material-containing agglomerates while moving the hearth in the moving-hearth reducing furnace to generate solid reduced iron and simultaneously thermally carbonizing the bedding carbonaceous material to generate char; hot-forming the solid reduced iron and the char into agglomerates without substantial cooling; continuously charging the agglomerates into the iron bath-type melting furnace from thereabove; and blowing oxygen-containing gas into the iron bath-type melting furnace to melt the solid reduced iron and to thereby generate molten iron.
    Type: Grant
    Filed: May 27, 2011
    Date of Patent: October 2, 2012
    Assignee: Kobe Steel, Ltd.
    Inventors: Takao Harada, Hidetoshi Tanaka, Kiminori Hajika, Tadashi Yaso, Toshiyuki Kurakake
  • Publication number: 20110226092
    Abstract: A process for producing molten iron with a combination of a moving-hearth reducing furnace and an iron bath-type melting furnace includes a step of charging a bedding carbonaceous material having an average particle diameter of 1 to 5 mm on a hearth of the moving-hearth reducing furnace and placing carbonaceous material-containing agglomerates containing a powdery iron oxide source and a powdery carbonaceous reductant on the bedding carbonaceous material; a step of thermally reducing the carbonaceous material-containing agglomerates while moving the hearth in the moving-hearth reducing furnace to generate solid reduced iron and simultaneously thermally carbonizing the bedding carbonaceous material to generate char; a step of continuously charging the solid reduced iron and the char into the iron bath-type melting furnace from thereabove without substantial cooling; and a step of blowing oxygen-containing gas into the iron bath-type melting furnace to melt the solid reduced iron and to thereby generate molt
    Type: Application
    Filed: May 27, 2011
    Publication date: September 22, 2011
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Takao HARADA, Hidetoshi Tanaka, Kiminori Hajika, Tadashi Yaso, Toshiyuki Kurakake
  • Patent number: 8012237
    Abstract: A process for producing molten iron is a process in which while an inert gas is blown into a molten iron layer in an iron bath type melting furnace through bottom-blown tuyeres provided in a hearth bottom thereof to stir the molten iron layer, a carbon material, an additive flux, and solid reduced iron obtained by heating reduction of carbon composite iron oxide briquettes are charged into the above melting furnace, and top blowing of an oxygen-containing gas is performed through a top-blown lance provided for the melting furnace, so that the solid reduced iron is melted by combustion heat obtained by combusting the carbon material and/or carbon in molten iron to form molten iron.
    Type: Grant
    Filed: September 18, 2008
    Date of Patent: September 6, 2011
    Assignee: Kobe Steel, Ltd.
    Inventors: Hideaki Fujimoto, Tsuyoshi Mimura, Takao Harada, Masataka Tateishi, Kiminori Hajika, Hiroshi Sugitatsu
  • Patent number: 7993430
    Abstract: The disclosure relates to improvements of technology for producing metallic iron by thermally reducing an iron source such as iron ore with a carbonaceous reductant such as coke by including efficiently reducing iron oxides into metallic iron at a lower operation temperature while conducting carburization, and efficiently separating the generated metallic iron from slag-forming components such as gangue components contained in raw material ore whereby metallic iron with controlled carbon concentrations can be produced in high yield.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: August 9, 2011
    Assignee: Kobe Steel, Ltd.
    Inventors: Takao Harada, Hidetoshi Tanaka, Kiminori Hajika, Tadashi Yaso, Toshiyuki Kurakake
  • Publication number: 20110156326
    Abstract: Disclosed is an iron bath-type melting furnace characterized by comprising a furnace body and a plurality of tap holes provided at different positions of the furnace body in the direction of the height thereof so as to extend through the furnace body, and in that an iron source as a raw material together with a carbon material and a slag-making material is charged into the furnace and further an oxygen-containing gas is injected into the furnace to melt the iron source as the raw material by combustion heat generated by combustion of the carbon material and/or carbon contained in the molten iron and to produce molten iron and molten slag are produced, and the plurality of the tap holes is used while switching from the uppermost tap hole toward downward tap holes to tap the iron slag being conducted, whereby molten iron is produced by intermittently taking out the molten iron and the molten slag to the outside of the furnace while maintaining the furnace body erect.
    Type: Application
    Filed: August 6, 2009
    Publication date: June 30, 2011
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel Ltd.)
    Inventors: Hideaki Fujimoto, Korehito Kadoguchi, Kiminori Hajika, Hiroshi Sugitatsu
  • Publication number: 20100229685
    Abstract: A process for producing molten iron is a process in which while an inert gas is blown into a molten iron layer in an iron bath type melting furnace through bottom-blown tuyeres provided in a hearth bottom thereof to stir the molten iron layer, a carbon material, an additive flux, and solid reduced iron obtained by heating reduction of carbon composite iron oxide briquettes are charged into the above melting furnace, and top blowing of an oxygen-containing gas is performed through a top-blown lance provided for the melting furnace, so that the solid reduced iron is melted by combustion heat obtained by combusting the carbon material and/or carbon in molten iron to form molten iron.
    Type: Application
    Filed: September 18, 2008
    Publication date: September 16, 2010
    Applicant: KABUSHIKI KAISHA KOBE SEIKO SHO (KOBE STEEL, LTD.)
    Inventors: Hideaki Fujimoto, Tsuyoshi Mimura, Takao Harada, Masataka Tateishi, Kiminori Hajika, Hiroshi Sugitatsu
  • Publication number: 20090090216
    Abstract: A process for producing molten iron with a combination of a moving-hearth reducing furnace and an iron bath-type melting furnace includes a step of charging a bedding carbonaceous material having an average particle diameter of 1 to 5 mm on a hearth of the moving-hearth reducing furnace and placing carbonaceous material-containing agglomerates containing a powdery iron oxide source and a powdery carbonaceous reductant on the bedding carbonaceous material; a step of thermally reducing the carbonaceous material-containing agglomerates while moving the hearth in the moving-hearth reducing furnace to generate solid reduced iron and simultaneously thermally carbonizing the bedding carbonaceous material to generate char; a step of continuously charging the solid reduced iron and the char into the iron bath-type melting furnace from thereabove without substantial cooling; and a step of blowing oxygen-containing gas into the iron bath-type melting furnace to melt the solid reduced iron and to thereby generate molt
    Type: Application
    Filed: March 16, 2007
    Publication date: April 9, 2009
    Applicant: Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
    Inventors: Takao Harada, Hidetoshi Tanaka, Kiminori Hajika, Tadashi Yaso, Toshiyuki Kurakake
  • Publication number: 20070295165
    Abstract: A bedding carbonaceous material is charged onto a hearth of a rotary hearth furnace, carbonaceous-material containing pellets containing powdery iron ore and powdery coal are placed on the bedding carbonaceous material, and the hearth is caused to pass inside the rotary hearth furnace to heat and reduce the carbonaceous-material containing pellets to solid reduced iron and to heat and dry the bedding carbonaceous material by distillation into char. Subsequently, the solid reduced iron and the char are charged into an iron-melting furnace without being substantially cooled, and an oxygen gas is blown into the iron-melting furnace to melt the solid reduced iron, thereby obtaining molten iron. At least a part of an exhaust gas from the iron-melting furnace is used as a fuel gas for the rotary hearth furnace after being cooled and having dust removed.
    Type: Application
    Filed: October 26, 2005
    Publication date: December 27, 2007
    Applicant: Kabushiki Kaisha Kobe Seiko Sho ( Kobe Steel ltd.)
    Inventors: Hidetoshi Tanaka, Tsuyoshi Mimura, Takao Harada, Kiminori Hajika, Tadashi Yaso, Toshiyuki Kurakake