Patents by Inventor Robert D. Stewart

Robert D. Stewart 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: 4268395
    Abstract: A process for transfer by extraction, of at least one species from a fluid phase to a first liquid phase receptive to such species, comprises intimately contacting the fluid phase with an emulsion of the first liquid phase in a second liquid phase which is permeable with respect to such species and substantially immiscible in the first liquid phase. The emulsion is stabilized by the second liquid phase containing at least one substantially insoluble particulate solid which is substantially non-reactive to constituents contained in each of such phases in an amount sufficient to form a stable emulsion. Transfer of the species is from the fluid phase through the second solids-containing liquid phase to the first liquid phase.In one embodiment, the first liquid phase is lean with respect to the species to be extracted. In another embodiment, mass action is utilized to maintain a driving force by counter-transport of a different ion.
    Type: Grant
    Filed: October 4, 1978
    Date of Patent: May 19, 1981
    Assignee: Babcock-Brown Boveri Reaktor GmbH
    Inventor: Robert D. Stewart
  • Patent number: 4227488
    Abstract: A fluidized bed combustion or gasification unit in which a grate is disposed in a housing to divide the housing into an upper chamber and a lower chamber. A bed of particulate material including burning fuel is supported by the grate and extends in the upper chamber. The lower chamber has an inlet for receiving pressurized air for passing through the lower chamber, the grate, and the bed of particulate material to fluidize the particulate material. A cooling device is provided for receiving the particulate material from the bed and cooling same prior to the material being discharged to external equipment.
    Type: Grant
    Filed: October 3, 1978
    Date of Patent: October 14, 1980
    Assignee: Foster Wheeler Energy Corporation
    Inventors: Robert D. Stewart, Robert L. Gamble
  • Patent number: 4177741
    Abstract: A system and method for improving the reaction efficiency of a fluidized bed combustor or reactor in which a combustion supporting gas is passed upwardly through a bed of particulate material to fluidize same and to entrain the relatively fine particulate material in the bed. The entrained material is separated from the gas and is agglomerated externally of the housing before being passed back into the fluidized bed.
    Type: Grant
    Filed: June 19, 1978
    Date of Patent: December 11, 1979
    Assignee: Foster Wheeler Energy Corporation
    Inventors: Robert D. Stewart, Robert L. Gamble
  • Patent number: 4133381
    Abstract: Leaching of water-soluble constituents from particles containing treated oil shale and including oxides of alkaline earth metals, such as particles in an in situ oil shale retort, is inhibited by contacting the particles with carbon dioxide in the presence of water for a sufficient time to produce a substantially water-insoluble and/or impermeable barrier of carbonates of alkaline earth metals at the surface of the particles.
    Type: Grant
    Filed: December 27, 1977
    Date of Patent: January 9, 1979
    Assignee: Occidental Oil Shale, Inc.
    Inventor: Robert D. Stewart
  • Patent number: 4130130
    Abstract: A valve comprising inlet means having a bore, a seat at one end of the bore and an annular outer edge portion. A primary orifice is defined by a valve member and the seat, and a secondary orifice is defined by the valve member and the outer edge portion. The valve member has a shroud portion formed to cause the cross sectional flow area of the secondary orifice to increase at a nonlinear rate as the valve member is raised from the seat. With these parts formed to provide a huddling chamber communicating between the primary and secondary orifices, the valve has a quick full opening, non-vibratory characteristic suitable for spring-loaded liquid pressure safety relief service.
    Type: Grant
    Filed: November 15, 1976
    Date of Patent: December 19, 1978
    Assignee: Crosby Valve & Gage Company
    Inventors: Robert D. Stewart, James A. Schretter
  • Patent number: 3944653
    Abstract: Antimony sulfide contained in an antimony sulfide bearing ore, such as stibnite, is converted to high purity antimony trichloride by reacting the antimony sulfide bearing ore with a source of chlorine to form high purity antimony trichloride and sulfur or hydrogen sulfide as separable by-products. The high purity antimony trichloride may be hydrolyzed to form high purity antimony oxide.
    Type: Grant
    Filed: October 9, 1973
    Date of Patent: March 16, 1976
    Assignee: Occidental Petroleum Corporation
    Inventors: Robert D. Stewart, John R. McKinley