Patents by Inventor David C. Grant

David C. Grant 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: 5230167
    Abstract: The removal of organics and volatile metals from soils using thermal desorption comprises moving contaminated materials, positioned on a belt conveyor, through a chamber under oxygen conditions, temperature conditions, and residence time effective to substantially avoid incineration of the contaminants. The method further comprises heating the contaminated material for volatilizing the contaminants and for producing a processed material that is substantially decontaminated. To carry the volatilized contaminants from the chamber, a transport gas may be passed through the chamber counter-current to the movement of the contaminated material. A gas stream including the volatilized contaminants and the transport gas may be passed through a condenser and through a scrubber for producing a substantially cleaned gas and a contaminated liquid concentrate. The cleaned gas may be recycled back into the chamber as the transport gas or passed through a gas cleaning system prior to discharge into the atmosphere.
    Type: Grant
    Filed: October 30, 1991
    Date of Patent: July 27, 1993
    Assignee: Westinghouse Electric Corp.
    Inventors: Edward J. Lahoda, David C. Grant
  • Patent number: 5133901
    Abstract: The concentrations of residual heavy metal contaminants in the particulate material in a slurry produced in a particulate material washing process are monitored on-line and can be used to control the washing process. In alternative embodiments of the invention, x-rays, thermal neutrons or laser beams are directed at the slurry as it flows through a flow cell to induce emission of secondary x-rays, gamma rays or light, respectively, characteristic of the heavy metal contaminants and constituents representative of the solids contents of the slurry. These characteristic energies are measured and used to determine the concentration in ppm of the residual heavy metal contaminants in the particulate material within the slurry.
    Type: Grant
    Filed: March 1, 1991
    Date of Patent: July 28, 1992
    Assignee: Westinghouse Electric Corp.
    Inventors: Steven H. Peterson, Edward J. Lahoda, David C. Grant, Edward F. Sverdrup, Thomas V. Congedo, John Bartko, Robert E. Witkowski, Arthur L. Wolfe, William D. Partlow, Michael C. Skriba
  • Patent number: 5128068
    Abstract: Particulate material such as for example soil contaminated with heavy metals, radioactive species and organics, singly or in combination, is treated by first washing the contaminated material with a contaminant mobilizing solution comprising a leaching agent, a surfactant or a mixture thereof. Large particles, typically greater than 5 mm are mechanically separated, washed with water and returned to the site as recovered soil. Fines, along with contaminants dissolved or dispersed in the contaminant mobilizing solution are separated from intermediate sized particles by a countercurrent flow of the contaminant mobilizing solution, preferably in a mineral jig. The intermediate sized particles are then abraded in an attrition scrubber to dislodge attached mineral slimes or fines. These additional fines are separated from the intermediate sized particles with a countercurrent flow of wash water in a second mineral jig.
    Type: Grant
    Filed: May 25, 1990
    Date of Patent: July 7, 1992
    Assignee: Westinghouse Electric Corp.
    Inventors: Edward J. Lahoda, David C. Grant, Edward F. Sverdrup
  • Patent number: 5045240
    Abstract: Waste material containing hazardous or radio-active species is treated by: separating a portion of the waste material and identifying the particle size range of the severely contaminated fraction by use of a sieving apparatus (6) and a contamination detection apparatus (8); passing the waste material (15) near a contamination detection apparatus (12) to identify the waste material that is contaminated and segregate that material by a diverter (17) to provide contaminated portion (19); passing the contaminated portion (19) into a fluidized bed apparatus (16) where an aqueous leaching solution (21), effective to leach soluble, contamination species, contacts the contaminated material at an upward velocity effective to remove the particle size range that is determined to contain the severely contaminated fraction of the waste material, to provide a severely contaminated effluent slurry (24); and removing the leach solution from the slurry in a dewatering apparatus (26) to provide a solution (27) containing solub
    Type: Grant
    Filed: May 1, 1989
    Date of Patent: September 3, 1991
    Assignee: Westinghouse Electric Corp.
    Inventors: Michael C. Skriba, David C. Grant
  • Patent number: 4863271
    Abstract: The apparatus of this invention is a composite combining prism for combining the beams of a ring laser gyro. It uses a composite prism whose trunk is fabricated of two substantially identical juxtaposed sub-prisms having beam splitters in the region where laser beams cross their common boundary. The beam splitter regions are very thin dielectric films, typically no thicker than a fraction of a wavelength of the laser light. Dielectric films, such as titanium dioxide, are used for the splitters so that the geometrical path lengths of interfering beams are almost exactly the same. To make the path lengths optically the same, the two sub-prisms and the substrate of the partly transmitting corner mirror of the ring laser preferably have the same index of refraction. In a first embodiment, the outwardly-extending trunk of the assembled composite prism is substantially rectangular in cross-section.
    Type: Grant
    Filed: February 2, 1988
    Date of Patent: September 5, 1989
    Assignee: Litton Systems, Inc.
    Inventors: David C. Grant, Kevin D. Grobsky, Joseph J. Purrazzella
  • Patent number: 4778628
    Abstract: Disclosed is an underground waste barrier structure that consists of waste material, a first container formed of activated carbonaceous material enclosing the waste material, a second container formed of zeolite enclosing the first container, and clay covering the second container. The underground waste barrier structure is constructed by forming a recessed area within the earth, lining the recessed area with a layer of clay, lining the clay with a layer of zeolite, lining the zeolite with a layer of activated carbonaceous material, placing the waste material within the lined recessed area, forming a ceiling over the waste material of a layer of activated carbonaceous material, a layer of zeolite, and a layer of clay, the layers in the ceiling cojoining with the respective layers forming the walls of the structure, and finally, covering the ceiling with earth.
    Type: Grant
    Filed: May 15, 1986
    Date of Patent: October 18, 1988
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Anuj J. Saha, David C. Grant
  • Patent number: 4383763
    Abstract: A mirror constrained to translation and whose position is controlled by a piezoelectric ceramic operating as a bimorph.
    Type: Grant
    Filed: May 8, 1981
    Date of Patent: May 17, 1983
    Assignee: Litton Systems, Inc.
    Inventors: Thomas J. Hutchings, David C. Grant, Jr., Gary D. Babcock
  • Patent number: 4317089
    Abstract: A ring laser wherein, in the preferred embodiment, the laser path is substantially square, and the path length is adjustable by making at least one of the mirrors slightly tilted and one of the mirrors concave with at least the concave mirror translatable.
    Type: Grant
    Filed: December 8, 1980
    Date of Patent: February 23, 1982
    Assignee: Litton Systems, Inc.
    Inventors: David C. Grant, Jr., Thomas J. Hutchings
  • Patent number: 4270802
    Abstract: The injection of an ammonium sulfite or bisulfite solution increases the permeability of an uranium ore bed that has suffered permeability losses during the in-situ mining of uranium with an alkaline leach solution containing a peroxide or dissolved oxygen oxidant. Such an injection recovers much of the lost formation permeability, thus decreasing costs and effort required to put needed restoration solutions or further leach solutions through the ore bed. In addition, uranium contamination of the ground water normally occurring after cessation of leaching is significantly lowered by such injection.
    Type: Grant
    Filed: January 3, 1980
    Date of Patent: June 2, 1981
    Assignee: The United States of America as represented bythe Secretary of the Interior
    Inventors: David C. Grant, Herbert A. Burgman
  • Patent number: 4000947
    Abstract: In a differential laser gyro system including a ring laser in the form of a figure eight incorporated in a solid block, optical readout is accomplished by mounting the readout optics to the block in a manner similar to that employed for the laser optics. The laser optics comprises four mirrors mounted on the outer face of the block, with diagonally opposite faces being parallel. A modulator having plane parallel end faces is incorporated in the laser optical system, and oriented so that readout reflections therefrom occur in a plane at a slight angle to the lasing plane. Readout beam director prisms are positioned on the outer faces of the block adjacent to the laser optic system mirrors, and direct the readout reflections to a beam splitter and then to optical detectors as in conventional readout optical systems. Alignment of the readout system is enhanced by virtue of the fact that both angular and linear adjustments can be made by rotating or translating the readout optics.
    Type: Grant
    Filed: May 27, 1975
    Date of Patent: January 4, 1977
    Assignee: United Technologies Corporation
    Inventor: David C. Grant, Jr.