Patents by Inventor Richard B. Greenwalt

Richard B. Greenwalt 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: 6355088
    Abstract: A method of upgrading relatively rich, fine-grained earthy hematite iron ores is provided. The iron ore, after suitable preparation, is reduced using a solid state reduction technique. As a result of the reduction process, the iron grains undergo size enhancement while the nonmetallic oxides are unreduced and remain as refractory oxide gangue. After completion of the reduction process, the enlarged malleable metallic iron grains are crushed in such a way as to cause the iron grains to fuse together, forming large, flat iron flakes. In order to achieve maximum flake size, the crushing system applies a relatively gradual pressing force rather than a rapid, impact type of force. As the large flakes are formed, the iron grains are liberated from the refractory oxide grains resulting in an increase in density. The crushing system causes non-iron oxide bonds to be broken, resulting in the formation of residual refractory particles generally with a grain size of less than 0.05 millimeters.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: March 12, 2002
    Assignee: Bechtel Corporation
    Inventor: Richard B. Greenwalt
  • Patent number: 6273265
    Abstract: The performance of a gravity separator is enhanced by providing a magnetic material on the separation surface of the gravity separator. A magnetically enhanced gravity concentration/separation apparatus is provided for enhancing separation of a target feed material from remaining feed materials in a feed mixture having a transport medium and feed materials which comprise the target feed material and the remaining feed materials. The target feed material is magnetic and generally has a higher specific gravity than any magnetic feed materials contained in the remaining feed materials. The separating apparatus comprises a gravity separator including a separation surface on which to flow the feed mixture.
    Type: Grant
    Filed: July 12, 2000
    Date of Patent: August 14, 2001
    Assignee: Bechtel Corporation
    Inventor: Richard B. Greenwalt
  • Patent number: 6197088
    Abstract: A method of liquid iron production using high sulfur fuels is provided in which the level of sulfur in the iron is maintained below 0.1%. The low sulfur content is achieved even in the presence of high sulfur concentrations in the reducing gases and without the introduction of lime or limestone. According to one aspect, liquid iron in the fusion zone of a smelting system is saturated with carbon, thereby desulfurizing the liquid iron. The carbon saturation level is at least 4.5% carbon by weight and preferably, at least 5.0% carbon by weight. According to another aspect, the desulfurization of the liquid iron is enhanced by elevating the tapping temperatures to temperatures in excess of 1465° C., and preferably of about 1490° C. According to another aspect, the desulfurization process is supplemented by the presence of significant levels of silicon and/or manganese, both of which are highly soluble in the liquid iron.
    Type: Grant
    Filed: March 15, 1999
    Date of Patent: March 6, 2001
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 6048382
    Abstract: A method of upgrading relatively rich, fine-grained earthy hematite iron ores is provided. The iron ore, after suitable preparation, is reduced using a solid state reduction technique. As a result of the reduction process, the iron grains undergo size enhancement while the nonmetallic oxides are unreduced and remain as refractory oxide gangue. After completion of the reduction process, the enlarged malleable metallic iron grains are crushed in such a way as to cause the iron grains to fuse together, forming large, flat iron flakes. In order to achieve maximum flake size, the crushing system applies a relatively gradual pressing force rather than a rapid, impact type of force. As the large flakes are formed, the iron grains are liberated from the refractory oxide grains resulting in an increase in density. The crushing system causes non-iron oxide bonds to be broken, resulting in the formation of residual refractory particles generally with a grain size of less than 0.05 millimeters.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: April 11, 2000
    Assignee: Bechtel Corporation
    Inventor: Richard B. Greenwalt
  • Patent number: 5958107
    Abstract: A method of shift conversion of CO to H.sub.2 so that the level of gas can be reduced to a level that preheating for direct reduction to 800 to 900.degree. C. can be accomplished wherein carbon deposition is not a factor.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: September 28, 1999
    Assignee: Bechtel Croup, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5630862
    Abstract: The invention provides a method for both disposing of an environmentally undesirable material comprising petroleum coke and the sulfur and heavy metals contained therein and of providing fuel for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier having an upper fuel charging end, a reduction gas discharging end, a lower molten metal and slag collection end, and means providing an entry for charging ferrous material into the melter gasifier; introducing a carbonaceous fuel including petroleum coke into the melter gasifier at the upper fuel charging end; blowing oxygen-containing gas into the petroleum coke to form at least a first fluidized bed of coke particles from the petroleum coke; introducing ferrous material into the melter gasifier through the entry means, reacting petroleum coke, oxygen and particulate ferrous material to combust the major portion of the petroleum coke to produce reduction gas and molten iron or steel preproducts containing heavy metals freed
    Type: Grant
    Filed: June 15, 1995
    Date of Patent: May 20, 1997
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5558696
    Abstract: The disclosure describes a method of direct steel making wherein liquid iron is produced in a melter gasifier system using a solid fuel reductant, preferably petroleum coke, and low silica containing iron ore, preferably less than 2.0% by weight, and the liquid iron is transferred directly to an oxygen blown steel making reactor for steel production and refining.
    Type: Grant
    Filed: December 15, 1993
    Date of Patent: September 24, 1996
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5470375
    Abstract: The present invention provides a method for processing environmentally undesirable materials including petroleum coke and the sulfur and heavy metals contained therein and agglomerated waste dust from an electric arc furnace and the zinc, cadmium, lead and iron oxides contained therein and of providing fuel and a charging material for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier. Metallized arc furnace waste dust material from a reduction furnace is introduced into the melter gasifier. The petroleum coke, oxygen and metallized waste dust material are reacted to produce reduction gas and molten iron from the iron oxides in the waste dust material. The molten iron contains the metals freed from combustion of the petroleum coke. The reduction gas is removed from the melter gasifier for use in the reduction furnace to produce an top off gas containing vapors of zinc, cadmium and lead.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: November 28, 1995
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5429658
    Abstract: The invention relates to a method for processing environmentally undesirable materials including petroleum coke and the sulfur and heavy metals contained therein and oily steel and iron ferrous waste from machine shop and steel and iron processing to provide fuel and a charging material for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier.
    Type: Grant
    Filed: March 28, 1994
    Date of Patent: July 4, 1995
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5413622
    Abstract: A method is provided to improve the production of hot direct reduced iron in a melter-gasifier; reduction furnace system. All of the reduction gas produced in the melter gasifier and the top gas produced in reduction furnace which has been stripped of CO.sub.2 are recycled to the reduction furnace. The reduction furnace is sized to process all this gas and bypassed direct reduced iron may result.
    Type: Grant
    Filed: December 16, 1993
    Date of Patent: May 9, 1995
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5397376
    Abstract: The invention provides a method for both disposing of an environmentally undesirable material comprising petroleum coke and the sulfur and heavy metals contained therein and of providing fuel for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier having an upper fuel charging end, a reduction gas discharging end, a lower molten metal and slag collection end, and means providing an entry for charging ferrous material into the melter gasifier; introducing petroleum coke into the melter gasifier at the upper fuel charging end; blowing oxygen-containing gas into the petroleum coke to form at least a first fluidized bed of coke particles from the petroleum coke; introducing ferrous material into the melter gasifier through the entry means, reacting petroleum coke, oxygen and particulate ferrous material to combust the major portion of the petroleum coke to produce reduction gas and molten iron or steel preproducts containing heavy metals freed from combustion of the petrole
    Type: Grant
    Filed: June 30, 1993
    Date of Patent: March 14, 1995
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5380352
    Abstract: The invention provides a method for both disposing of an environmentally undesirable material comprising rubber tires and the sulfur and metals contained therein and of providing fuel for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier. The metals freed from combustion of the rubber tires is contained in the molten iron and sulfur freed from combustion of the rubber tires is contained in the slag.
    Type: Grant
    Filed: May 18, 1993
    Date of Patent: January 10, 1995
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5354356
    Abstract: The invention provides a method for both disposing of an environmentally undesirable material comprising petroleum coke and the sulfur and heavy metals contained therein and of providing fuel for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier having an upper fuel charging end, a reduction gas discharging end, a lower molten metal and slag collection end, and means providing an entry for charging ferrous material into the melter gasifier; introducing petroleum coke into the melter gasifier at the upper fuel charging end; blowing oxygen-containing gas into the petroleum coke to form at least a first fluidized bed of coke particles from the petroleum coke; introducing ferrous material into the melter gasifier through the entry means, reacting petroleum coke, oxygen and particulate ferrous material to combust the major portion of the petroleum coke to produce reduction gas and molten iron or steel preproducts containing heavy metals freed from combustion of the petrole
    Type: Grant
    Filed: December 17, 1992
    Date of Patent: October 11, 1994
    Assignee: Bechtel Group Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5338336
    Abstract: The present invention provides a method for processing environmentally undesirable materials including petroleum coke and the sulfur and heavy metals contained therein and agglomerated waste dust from an electric arc furnace and the zinc, cadmium, lead and iron oxides contained therein and of providing fuel and a charging material for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier. Metallized arc furnace waste dust material from a reduction furnace is introduced into the melter gasifier. The petroleum coke, oxygen and metallized waste dust material are reacted to produce reduction gas and molten iron from the iron oxides in the waste dust material. The molten iron contains the metals freed from combustion of the petroleum coke. The reduction gas is removed from the melter gasifier for use in the reduction furnace to produce an top off gas containing vapors of zinc, cadmium and lead.
    Type: Grant
    Filed: June 30, 1993
    Date of Patent: August 16, 1994
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5320676
    Abstract: The invention relates to a method of making iron or steel preproducts and reduction gas with a low slag forming process utilizing petroleum coke as a fuel in a melter gasifier.
    Type: Grant
    Filed: July 29, 1993
    Date of Patent: June 14, 1994
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5259865
    Abstract: The invention relates to a method of making iron or steel preproducts and reduction in gas a substantially slag free process utilizing petroleum coke as a fuel in a melter gasifier.
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: November 9, 1993
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 5259864
    Abstract: The invention provides a method for both disposing of an environmentally undesirable material comprising petroleum coke and the sulfur and heavy metals contained therein and of providing fuel for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier having an upper fuel charging end, a reduction gas discharging end, a lower molten metal and slag collection end, and means providing an entry for charging ferrous material into the melter gasifier; introducing petroleum coke into the melter gasifier at the upper fuel charging end; blowing oxygen-containing gas into the petroleum coke to form at least a first fluidized bed of coke particles from the petroleum coke; introducing ferrous material into the melter gasifier through the entry means, reacting petroleum coke, oxygen and particulate ferrous material to combust the major portion of the petroleum coke to produce reduction gas and molten iron or steel preproducts containing heavy metals freed from combustion of the petrole
    Type: Grant
    Filed: October 6, 1992
    Date of Patent: November 9, 1993
    Assignee: Bechtel Group, Inc.
    Inventor: Richard B. Greenwalt
  • Patent number: 4416688
    Abstract: The process for beneficiating iron ore, particularly high phosphorous iron ore, by controlled selective solid-state reduction in which the resultant sponge iron is produced in a malleable condition followed by ultrafine preferential grinding to form flake powder of the sponge iron and produce finely divided oxide gangue, including the phosphate bearing materials, and separation of said flake powder and finely divided gangue by conventional concentration techniques to obtain a high iron flake powder concentrate.
    Type: Grant
    Filed: January 28, 1982
    Date of Patent: November 22, 1983
    Assignee: Raymond Kaiser Engineers, Inc.
    Inventor: Richard B. Greenwalt