Patents Assigned to Iron Dynamics, Inc.
  • Patent number: 5972066
    Abstract: The present invention provides a method for producing direct reduced iron in a continuous and efficient fashion, which includes providing a mixture of a particulate iron oxide composition and a particulate carbonaceous reductant composition; the mixture being substantially unagglomerated and having a moisture content of less than about 14% water by weight; positioning the mixture onto a rotary hearth furnace; subjecting the mixture to reducing conditions to reduce a substantial portion of the iron oxide, thereby producing sponge iron; and discharging the sponge iron from the rotary hearth furnace.
    Type: Grant
    Filed: April 22, 1997
    Date of Patent: October 26, 1999
    Assignee: Iron Dynamics, Inc.
    Inventor: Larry J. Lehtinen
  • Patent number: 5961055
    Abstract: The present invention relates to upgrading iron ore to decrease the amount of nonferrous materials therein, and to thereby increase the iron content thereof. More particularly, the invention relates to a process utilizing magnetic fields to separate a significant amount of non-magnetic material, such as silica or pyrolusite, from valuable iron oxide in an iron ore or iron ore concentrate. The invention therefore finds advantageous use to provide an improved source of iron oxides for high purity uses such as, for example, direct reduction processes and heavy media coal beneficiation processes.
    Type: Grant
    Filed: November 5, 1997
    Date of Patent: October 5, 1999
    Assignee: Iron Dynamics, Inc.
    Inventor: Larry J. Lehtinen