Patents by Inventor Frank M. Stephens, Jr.
Frank M. Stephens, Jr. 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).
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Process for the production of iron carbide from iron oxide using external sources of carbon monoxide
Patent number: 6428763Abstract: The present invention is a process for the rapid conversion of iron oxide-containing material into iron carbide. The process includes a first step in which the iron oxide-containing material is contacted with a reducing gas that contains a high concentration of hydrogen gas to form a metallic iron-containing intermediate product and a second step in which the metallic iron-containing product is contacted with a carburizing gas having high concentrations of hydrogen and carbon monoxide gas to produce iron carbide. The unused carbon monoxide in the off-gas from the second step is not recycled to the second step but is used as a fuel source.Type: GrantFiled: March 22, 2000Date of Patent: August 6, 2002Assignee: Iron Carbide Holdings, Ltd.Inventors: Frank M. Stephens, Jr., Frank A. Stephens, Robert F. Hogsett, John P. Hager -
Patent number: 6328946Abstract: The present invention is a process for the conversion of iron-containing material into iron carbide. The process includes a first step in which the iron-containing material is contacted with a reducing gas that contains no more than a small amount of reactive carbon to produce metallic iron and a second step in which the metallic iron is contacted with a reducing and carburizing gas to produce iron carbide. The reducing and carburizing gas includes reactive carbon, hydrogen, and methane. The iron carbide product is of high purity.Type: GrantFiled: February 8, 1999Date of Patent: December 11, 2001Assignee: Iron Carbide Holdings, Ltd.Inventor: Frank M. Stephens, Jr.
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Patent number: 5869018Abstract: The present in a process for the conversion of iron-containing material into iron carbide. The process includes a first step in which the iron-containing material is contacted with a reducing gas that contains no more than a small amount of reactive carbon to produce metallic iron and a second step in which the metallic iron is contacted with a reducing and carburizing gas to produce iron carbide.The reducing and carburizing gas includes reactive carbon, hydrogen, and methane. The iron carbide product is of high purity.Type: GrantFiled: January 14, 1994Date of Patent: February 9, 1999Assignee: Iron Carbide Holdings, Ltd.Inventor: Frank M. Stephens, Jr.
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Patent number: 5810906Abstract: The present invention provides a two-stage method for pretreating an iron oxide-containing feed material prior to conversion of the material into an iron carbide-containing product. The feed material is heated in the first stage in an oxidizing atmosphere to volatilize and/or thermally stabilize sulfide sulfur and evaporate moisture and heated in a reducing atmosphere in the second stage to reduce ferric iron to ferrous iron. The reduced material is then introduced into a system in which the iron oxides are substantially converted to iron carbide.Type: GrantFiled: August 28, 1996Date of Patent: September 22, 1998Assignee: Iron Carbide Holdings, Ltd.Inventor: Frank M. Stephens, Jr.
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Patent number: 5804156Abstract: A process for producing iron carbide in a fluid bed reactor in which the pressure is maintained in excess of the pressure at which the mole fraction of hydrogen in the process gas begins to decrease. The hydrogen concentration may also be increased above the equilibrium concentration for hydrogen at the temperature and pressure in the reactor. Further improvements are gained by preheating a iron ore reactor feed in which the iron oxide is primarily in the form of hematite under a reducing atmosphere, and using at least two fluid bed reactors in series.Type: GrantFiled: July 19, 1996Date of Patent: September 8, 1998Assignee: Iron Carbide Holdings, Ltd.Inventors: Gordon H. Geiger, Arden W. Swanson, Frank A. Stephens, Frank M. Stephens, Jr.
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Patent number: 5733357Abstract: A process for converting iron oxide to iron carbide using hydrogen as a reducing gas. Water is generated by the reduction of the iron oxides using hydrogen. The amount of water present in the reactor system is controlled and the water is contacted with methane in order to internally generate carbon monoxide and/or carbon dioxide gas. The carbon monoxide and/or carbon dioxide is subsequently employed to carburize the iron to iron carbide.Type: GrantFiled: February 5, 1996Date of Patent: March 31, 1998Assignee: Iron Carbide Holdings, Ltd.Inventors: Frank M. Stephens, Jr., Frank A. Stephens, Robert F. Hogsett
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Patent number: 5366897Abstract: A process for controlling the conversion of reactor feed to iron carbide is disclosed. The reactor feed is subjected to a process gas in a fluidized bed reactor (10), and the off-gas from this reaction is analyzed (56) to determine its composition and the temperature (64) and pressure (66). A stability phase diagram is generated based on the temperature. Different regions of the stability phase diagram are representative of different products being formed by the conversion of the reactor feed. Based on relative concentrations of the individual gases in the off-gas and the total pressure, a point is plotted on the stability phase diagram indicative of the favored reaction product. The process parameters can then be adjusted to insure that iron carbide can be produced from the reactor feed based on the stability phase diagram. In one embodiment, the rate of conversion of the reactor feed into iron carbide is controlled.Type: GrantFiled: January 27, 1993Date of Patent: November 22, 1994Assignee: Iron Carbide Holdings, Ltd.Inventors: John P. Hager, Frank A. Stephens, Frank M. Stephens, Jr.
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Patent number: 5137566Abstract: A novel process for the conversion of reactor feed to iron carbide is provided. The process includes the step of preheating the reactor feed in an oxidizing atmosphere. The iron carbide produced by the process is particularly useful in the production of steel.Type: GrantFiled: August 1, 1990Date of Patent: August 11, 1992Assignee: Iron Carbide Holdings, LimitedInventors: Frank M. Stephens, Jr., John P. Hager, Frank A. Stephens
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Patent number: 5118479Abstract: A novel design for a fluidized bed reactor is provided. The fluidized bed reactor includes a baffle system to ensure the proper residence time of the feed materials. The fluidized bed reactor also provides a novel method for reducing the negative effects of thermal expansion in the reactor.Type: GrantFiled: August 1, 1990Date of Patent: June 2, 1992Assignee: Iron Carbide Holdings, LimitedInventors: Frank M. Stephens, Jr., John P. Hager, Frank A. Stephens
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Patent number: 5073194Abstract: A method of controlling product quality in a conversion of reactor feed to an iron carbide-containing product in a fluidized bed reactor. A Mossbauer analysis is performed on product samples leaving the fluidized bed reactor, and a regression analysis is performed on the Mossbauer data. Depending upon the results of the regression analysis, process parameters are adjusted in order to obtain a product having a desired composition. Adjustments are made to the temperature and pressure in the fluidized bed reactor, rate of feed to the fluidized bed reactor, and the composition of the process gas which reacts with the reactor feed in the fluidized bed reactor, dependent upon the analysis results.Type: GrantFiled: August 1, 1990Date of Patent: December 17, 1991Assignee: Iron Carbide Holdings, LimitedInventors: Frank A. Stephens, John P. Hager, Frank M. Stephens, Jr.
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Patent number: 4398945Abstract: The object of the invention is to provide a process for the recovery of iron and nickel from low iron content laterite ores.Said process comprises subjecting the ore to a carburizing step in the presence of a reducing agent and carbon supplying agent to convert the iron to iron carbide, followed by smelting the residue or product of the carburizing step to produce a ferronickel product.An alternative embodiment is the recovery of the iron and nickel from the product of the carburizing step by magnetic separation.Type: GrantFiled: June 22, 1981Date of Patent: August 16, 1983Inventor: Frank M. Stephens, Jr.
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Patent number: 4396423Abstract: The object of the invention is to provide a process for the recovery of iron and zinc from steel making flue dust.The process comprises subjecting the flue dust to a carbiding step in a fluid bed in the presence of a reducing agent and a carbon supplying agent to break down the zinc ferrite structure and convert the iron to iron carbide, followed by heating the residue or product of the carbiding step to recover zinc by evaporization.The iron carbide produced may be introduced into a steel making furnace for the production of steel.An alternative procedure is the recovery of iron carbide and zinc by magnetic separation from the gangue after the carbiding step and before separation of zinc from iron carbide.Type: GrantFiled: June 22, 1981Date of Patent: August 2, 1983Inventors: Frank M. Stephens, Jr., James C. Blair
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Patent number: 4372755Abstract: A fuel gas containing methane is produced from a carbonaceous material in a single reaction zone by reacting the carbonaceous material in the presence of a stabilized metal carbide catalyst and water vapor and/or carbon dioxide at a temperature of from about 500.degree. C. to about 900.degree. C. The water vapor and/or carbon dioxide is maintained in an amount of from about 10 to about 30 percent by volume.Type: GrantFiled: October 30, 1980Date of Patent: February 8, 1983Assignee: Enrecon, Inc.Inventors: Radon Tolman, Frank M. Stephens, Jr.
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Patent number: 4257781Abstract: In the field of chemical fuels, prior art coal gasification produces a fuel value of a mixture of carbon monoxide and hydrogen which has a lower BTU than methane. The present process uses coal resources more economically for industry by converting part of the hydrogen and part of the carbon in the carbon monoxide of the gas mixture to methane, by continuously introducing the gas mixture into a fluid bed in the presence of iron under conditions of pressure and temperature which promote the reduction of carbon monoxide to carbon, the formation of iron carbide from the iron and carbon, and the formation of methane and iron from iron carbide and hydrogen, and continuously removing from the fluid bed a methane enriched gas mixture including carbon monoxide and hydrogen having a substantially increased fuel value over the gas mixture introduced into the fluid bed.Type: GrantFiled: January 12, 1979Date of Patent: March 24, 1981Assignee: Hazen Research, Inc.Inventor: Frank M. Stephens, Jr.
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Patent number: 4134907Abstract: A process for increasing the fuel value of a gas mixture of carbon monoxide and hydrogen by converting part of the hydrogen and part of the carbon in the carbon monoxide of the gas mixture to methane, which comprises continuously introducing the gas mixture into a fluid bed in the presence of iron under conditions of pressure and temperature which promote the reduction of carbon monoxide to carbon, the formation of iron carbide from the iron and carbon, and the formation of methane and iron from iron carbide and hydrogen, and continuously removing from the fluid bed a methane enriched gas mixture including carbon monoxide and hydrogen having a substantially increased fuel value over the gas mixture introduced into the fluid bed.Type: GrantFiled: July 21, 1977Date of Patent: January 16, 1979Assignee: Hazen Research, Inc.Inventor: Frank M. Stephens, Jr.
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Patent number: 4053301Abstract: A process for the direct production of steel from particulate iron oxides or concentrates including two major steps in which in Step (1) the iron oxides are converted to iron carbide and in Step (2) steel is produced directly from the carbide in the basic oxygen furnace or the electric furnace. In the production of the carbide the oxides are reduced and carburized in a single operation using a mixture of hydrogen as a reducing agent and carbon bearing substances such as propane primarily as carburizing agents. Iron carbide thus produced is introduced as all or part of the charge into a basic oxygen furnace to produce steel directly without the blast furnace step. In order to make the steel making process auto-thermal, heat is supplied either by using the hot iron carbide from Step (1) or preheating the iron carbide or by including sufficient fuel in the iron carbide to supply the required heat by combustion.Type: GrantFiled: October 14, 1975Date of Patent: October 11, 1977Assignee: Hazen Research, Inc.Inventor: Frank M. Stephens, Jr.
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Patent number: 4039324Abstract: Copper is recovered from copper salts, e.g. cuprous chloride, by means of a process comprising reducing the copper salts with hydrogen in a fluidized bed in the presence of chemically inert, generally spherical, relatively smooth, non-porous particles in order to restrain sintering of the reduced copper.Type: GrantFiled: November 14, 1975Date of Patent: August 2, 1977Assignee: Cyprus Metallurgical Processes CorporationInventors: Frank M. Stephens, Jr., James C. Blair
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Patent number: RE32247Abstract: A process for the direct production of steel from particulate iron oxides or concentrates including two major steps in which in Step (1) the iron oxides are converted to iron carbide and in Step (2) steel is produced directly from the carbide in the basic oxygen furnace or the electric furnace. In the production of the carbide the oxides are reduced and carburized in a single operation using a mixture of hydrogen as a reducing agent and carbon bearing substances such as propane primarily as carburizing agents. Iron carbide thus produced is introduced as all or part of the charge into a basic oxygen furnace to produce steel directly without the blast furnace step. In order to make the steel making process auto-thermal, heat is supplied either by using the hot iron carbide from Step (1) or preheating the iron carbide or by including sufficient fuel in the iron carbide to supply the required heat by combustion.Type: GrantFiled: April 2, 1985Date of Patent: September 16, 1986Assignee: Hazen Research, Inc.Inventor: Frank M. Stephens, Jr.