Patents by Inventor Larry J. Lehtinen

Larry J. Lehtinen 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: 9579660
    Abstract: A method, process or system for producing an iron oxide concentrate from a treatment slurry of a low grade mineral assemblage includes mixing a flocculant with the treatment slurry and dewatering the treatment slurry before passing the treatment slurry through a wet high intensity magnetic separator of a type that employs a flux amplifying matrix (i.e., a WHIMS-FAM device) and recovering an iron oxide concentrate fraction and a tailings fraction from the WHIMS-FAM device. Another method, process or system for producing an iron oxide concentrate includes passing the treatment slurry through a WHIMS-FAM device and recovering an iron oxide concentrate fraction slurry and a tailings fraction slurry from the WHIMS-FAM device; mixing a flocculant with the concentrate fraction slurry and dewatering the concentrate slurry to provide a thickened concentrate slurry before filtering the thickened concentrate slurry to provide a concentrate filter cake.
    Type: Grant
    Filed: June 20, 2013
    Date of Patent: February 28, 2017
    Assignee: MagGlobal, LLC
    Inventor: Larry J. Lehtinen
  • Publication number: 20130341250
    Abstract: A method, process or system for producing an iron oxide concentrate from a treatment slurry of a low grade mineral assemblage includes mixing a flocculant with the treatment slurry and dewatering the treatment slurry before passing the treatment slurry through a wet high intensity magnetic separator of a type that employs a flux amplifying matrix (i.e., a WHIMS-FAM device) and recovering an iron oxide concentrate fraction and a tailings fraction from the WHIMS-FAM device. Another method, process or system for producing an iron oxide concentrate includes passing the treatment slurry through a WHIMS-FAM device and recovering an iron oxide concentrate fraction slurry and a tailings fraction slurry from the WHIMS-FAM device; mixing a flocculant with the concentrate fraction slurry and dewatering the concentrate slurry to provide a thickened concentrate slurry before filtering the thickened concentrate slurry to provide a concentrate filter cake.
    Type: Application
    Filed: June 20, 2013
    Publication date: December 26, 2013
    Inventor: Larry J. Lehtinen
  • Publication number: 20120210824
    Abstract: There are provided methods, systems and processes for forming cold bonded agglomerates in the form of pellets, briquettes or compacts from iron oxide materials, such as iron ore concentrates. The cold bonded agglomerates have sufficient strength and durability to be handled and shipped without significant damage. Forming the iron ore concentrate product into agglomerates facilitates the shipment and handling of the product and places the product in a form that is suitable for use by a wider variety of iron making customer facilities. There are also provided methods, systems and devices for handling greenballs as they cure, and before they have gained sufficient strength for significant handling, stockpiling or shipping.
    Type: Application
    Filed: February 14, 2012
    Publication date: August 23, 2012
    Inventors: Larry J. Lehtinen, Lucas J. Lehtinen
  • Patent number: 7901585
    Abstract: There are provided methods and processes that employ a mercury-adsorbing granular material as a sorbent to remove mercury from fluids. The fluids can be waste fluids that result from manufacturing, processing, or other treatment processes or systems. The fluids can also be fluids that are treated in their natural state. The fluids to be treated may include water, air, sludge, slurries, gases from processing or furnaces flues, gaseous flows, liquid flows, and other gases and liquids. In one excellent form of the invention, the mercury-adsorbing material includes taconite tailings.
    Type: Grant
    Filed: November 23, 2009
    Date of Patent: March 8, 2011
    Assignee: Ferro, LLC
    Inventors: Larry J. Lehtinen, Jeffrey A. Hansen
  • Patent number: 7666318
    Abstract: There are provided methods and processes that employ a mercury-adsorbing granular material as a sorbent to remove mercury from fluids. The fluids can be waste fluids that result from manufacturing, processing, or other treatment processes or systems. The fluids can also be fluids that are treated in their natural state. The fluids to be treated may include water, air, sludge, slurries, gases from processing or furnaces flues, gaseous flows, liquid flows, and other gases and liquids. In one excellent form of the invention, the mercury-adsorbing material includes taconite tailings.
    Type: Grant
    Filed: May 12, 2006
    Date of Patent: February 23, 2010
    Assignee: Ferro, LLC
    Inventors: Larry J. Lehtinen, Jeffrey A. Hansen
  • 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