Patents by Inventor Akihiko Akada

Akihiko Akada 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: 5178667
    Abstract: A pyrometallurgical refining process for obtaining one or both of zinc and lead from a sulfide concentrate, in which an iron-silicate slag or iron-silicate slag containing lime is formed and the sulfide concentrate, incombustible materials, and flux, together with at least one of industrial oxygen, oxygen-enriched air, or air, are blown into the slag to cause a reaction; as a result of the reaction, the major part of the zinc and part of the lead in the sulfide concentrate and the incombustible materials are dissolved in the slag, to arrange the slag and a matte and/or metal from one part of the lead in the raw material. A reducing agent such as heavy oil, pulverized coal, powdered coke, or the like is blown through the resulting slag, and the zinc and the lead in the slag are volatilized then condensed to obtain molten zinc and molten lead.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: January 12, 1993
    Assignee: Sumitomo Metal Mining Company Limited
    Inventors: Nobumasa Kemori, Akihiko Akada, Hitoshi Takano, Takeshi Kusakabe, Masaru Takebayashi
  • Patent number: 5174746
    Abstract: A method for operation of a flash smelting furnace comprising a reaction shaft, a settler connected at one end thereof to the lower portion of the reaction shaft and having a slag discharge port and a matte discharge port disposed on the side thereof, an uptake connected to the other end of the settler and at least one concentrate burner disposed to at least one of the top of the reaction shaft and the ceiling of the settler, in which the concentrate burner comprises at least a concentrate shoot, an oxygen blowing tube inserted in the concentrate shoot and an auxiliary fuel burner inserted into the oxygen blowing tube. In this method, the lower end of the oxygen blowing tube is protruded downward to lower than the lower end of the concentrate shoot and an amount of oxygen at least greater than that required for the auxiliary fuel is blown as an industrial oxygen by way of the oxygen blowing tube into the furnace. Oxygen efficiency can be improved remarkably while the rate of dust occurrence can be reduced.
    Type: Grant
    Filed: April 6, 1992
    Date of Patent: December 29, 1992
    Assignee: Sumitomo Metal Mining Company Limited
    Inventors: Nobumasa Kemori, Akihiko Akada, Yasuhiro Kondou