Frank A Stephens

US Patent:

6428763, Aug 6, 2002

Filed:

Mar 22, 2000

Appl. No.:

09/532583

Inventors:

Frank A. Stephens - Arvada CO
Robert F. Hogsett - Arvada CO
John P. Hager - Golden CO

Assignee:

Iron Carbide Holdings, Ltd. - Lakewood CO

International Classification:

C01B 3130

US Classification:

423439

Abstract:

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.

US Patent:

RE322474, Sep 16, 1986

Filed:

Apr 2, 1985

Appl. No.:

6/719967

Inventors:

Frank M. Stephens - Lakewood CO

Assignee:

Hazen Research, Inc. - Golden CO

International Classification:

C21C 552
C22B 110

US Classification:

75 11

Abstract:

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.

US Patent:

43964230, Aug 2, 1983

Filed:

Jun 22, 1981

Appl. No.:

6/275799

Inventors:

Frank M. Stephens - Lakewood CO
James C. Blair - Wheat Ridge CO

International Classification:

C22B 1930
C21B 1500

US Classification:

75 25

Abstract:

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.

US Patent:

50731947, Dec 17, 1991

Filed:

Aug 1, 1990

Appl. No.:

7/561077

Inventors:

Frank A. Stephens - Arvada CO
John P. Hager - Golden CO
Frank M. Stephens - Lakewood CO

Assignee:

Iron Carbide Holdings, Limited - Lakewood CO

International Classification:

C22B 514
C01B 3130

US Classification:

75376

Abstract:

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.

US Patent:

63289466, Dec 11, 2001

Filed:

Feb 8, 1999

Appl. No.:

9/246062

Inventors:

Frank M. Stephens - Lakewood CO

Assignee:

Iron Carbide Holdings, Ltd. - Lakewood CO

International Classification:

C01B 3130

US Classification:

423439

Abstract:

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.

US Patent:

42577810, Mar 24, 1981

Filed:

Jan 12, 1979

Appl. No.:

6/002956

Inventors:

Frank M. Stephens - Lakewood CO

Assignee:

Hazen Research, Inc. - Golden CO

International Classification:

C10K 304

US Classification:

48197R

Abstract:

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.

US Patent:

51375664, Aug 11, 1992

Filed:

Aug 1, 1990

Appl. No.:

7/561189

Inventors:

Frank M. Stephens - Lakewood CO
John P. Hager - Golden CO
Frank A. Stephens - Arvada CO

Assignee:

Iron Carbide Holdings, Limited - Lakewood CO

International Classification:

C22B 514
C01B 3130

US Classification:

75507

Abstract:

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.

US Patent:

57333572, Mar 31, 1998

Filed:

Feb 5, 1996

Appl. No.:

8/596954

Inventors:

Frank M. Stephens - Lakewood CO
Frank A. Stephens - Arvada CO
Robert F. Hogsett - Arvada CO

Assignee:

Iron Carbide Holdings, Ltd. - Lakewood CO

International Classification:

C22B 514
C01B 3130

US Classification:

75444

Abstract:

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.