Patents Represented by Attorney L. R. Cassett
  • Patent number: 4861361
    Abstract: Argon and nitrogen are separated from a gaseous stream containing them in combination with oxygen in a three-step process comprising introducing the gaseous stream under pressure to a noncryogenic separator to produce therein a stream enriched in nitrogen and argon, introducing said stream into a cryogenic distillation column to produce a high purity nitrogen product. An argon-rich side stream withdrawn from the cryogenic distillation column is introduced into a pressure swing adsorption unit to provide a crude argon product containing 97 percent or more of argon. The first noncryogenic separator may be a pressure swing adsorption unit or a gas diffusion zone.
    Type: Grant
    Filed: September 27, 1988
    Date of Patent: August 29, 1989
    Assignee: The BOC Group, Inc.
    Inventors: Ravi Jain, Alberto LaCava, Mark J. Andrecovich, Donald L. MacLean
  • Patent number: 4853004
    Abstract: The improvement in the separation of a gaseous mixtures by pressure swing adsorption (PSA) is disclosed. The interparticle voids in conventional PSA adsorbent beds are filled with fine particles. The ratio of the smallest dimension of the coarse adsorbent particles to the largest dimension of the fine particles, the size of the fine particles themselves and the present of volume of the fine particles in the bed are all critical to optimum PSA performance. The fine particles may be comminuted adsorbent or an inert material, i.e. one having no adsorptive capacity.
    Type: Grant
    Filed: January 20, 1988
    Date of Patent: August 1, 1989
    Assignee: The BOC Group, Inc.
    Inventors: Robert H. Kaplan, Alberto LaCava, Arthur I. Shirley, Steven M. Ringo
  • Patent number: 4848985
    Abstract: A compressed gas mixture, particularly air, is separated in absorbent beds 6 and 8 in turn. The adsorbent adsorbs a first component in preference to, or more rapidly than, second and third components. Accordingly, product gas rich in the second component is delivered to the pipeline 44. While one bed adsorbs the first component from compressed gas mixture, the other is regenerated by being placed in communication with the atmosphere through vent pipe 30. At the end of each adsorption step, the respective bed 6 or 8 is placed in communication with a bed 12 of adsorbent that adsorbs the second component more rapidly than, or in preference to, the first and third components, and the pressure between the two beds is equalized. The pressure between the beds 6 and 8 is then equalized. Unadsorbed gas comprising the first and third components is vented from bed 12 to the atmosphere and then the bed 12 is placed in communication with either bed 6 or bed 8 to cause the desired product, i.e.
    Type: Grant
    Filed: July 15, 1988
    Date of Patent: July 18, 1989
    Assignee: The BOC Group, plc
    Inventor: Piotr J. Sadkowski
  • Patent number: 4846267
    Abstract: Aluminum alloys suitable for fabrication into plate and fin type heat exchangers are subjected to a chemical etching procedure in order to improve the heat transfer efficiency thereof. Applicants have found that a high temperature heat treatment of an aluminum alloy plate material to produce a precipitate, followed by exposure to an etching composition, results in a heat exchanger surface modified by the formation of pits. The heat exchangers so modified may be advantageously used in the reboiler/condensor section of air separation units.
    Type: Grant
    Filed: March 14, 1988
    Date of Patent: July 11, 1989
    Assignee: The BOC Group, Inc.
    Inventors: Walter J. Shattes, Nikhiles Bandyopadhyay, Paul C. Krueger
  • Patent number: 4843828
    Abstract: In a distillation column used in the separation of air, a liquid stream of composition intermediate those occuring at the top and bottom is taken from the column and is at least partial reboiled in an external heat exchanger by heat exchange with a heat exchange fluid. The resultant vapor is returned to the column. Its composition matches that of the vapor in the vapor space to which it is returned more closely than that of the vapor in the vapor space above the tray from which the liquid is taken for reboil. The heat exchange fluid is other than one which is taken from a liquid vapor contact column, is passed directly to the heat exchanger, and is then returned directly to the column from which it was taken.
    Type: Grant
    Filed: April 15, 1988
    Date of Patent: July 4, 1989
    Assignee: The BOC Group, plc
    Inventor: David C. F. Gladman
  • Patent number: 4108107
    Abstract: A substrate or part holder is disclosed which allows rotation of at least two parts about their individual axes as well as rotation of all of the parts about a main axis. The part holder has a stub shaft for receiving each part, and a hollow housing attached to the end of a hollow shaft. An interior shaft is rotatable inside the hollow shaft and a central gear engages a gear on each stub shaft inside of the housing. Means are provided for mounting a part on each stub shaft outside of the housing. Rotation of the hollow shaft will cause rotation of all of the parts about the common axis, while any differential in rotation between the hollow shaft and the interior shaft will cause rotation of each part about the axis of the stub shaft to which it is attached.
    Type: Grant
    Filed: April 1, 1976
    Date of Patent: August 22, 1978
    Assignee: Airco, Inc.
    Inventor: Glen R. Scheuermann
  • Patent number: 4103324
    Abstract: Power supply of the saturable reactor type is disclosed. The improvement is the inclusion of a variable impedance network, such as a pair of opposed semiconductor controlled rectifiers, in series with the current winding of the saturable reactor. Also included is an electronic circuit for changing the impedance of the variable impedance circuit, such as a control circuit for monitoring an operating parameter and for enabling or disabling the firing of the semiconductor controlled rectifiers in response to a change in the operating parameter. A preferred embodiment of the power supply also includes a transformer and a rectifier for supplying high-voltage, direct current to a sputtering apparatus.
    Type: Grant
    Filed: December 22, 1976
    Date of Patent: July 25, 1978
    Assignee: Airco, Inc.
    Inventors: C. Keith Vandervelden, William P. Blake
  • Patent number: 4101731
    Abstract: A composite multifilament superconducting structure is provided, which includes an elongated substrate-carrying, longitudinally-directed, sputtered discrete filament of an A-15 type intermetallic superconductor. In a preferable procedure, a plurality of spaced, generally longitudinal grooves are formed on the surface of an elongated filamentary substrate, preferably a metal wire. The walls of the grooves on the substrate surface are shaped to undercut the curvilinear surface of the substrate located between two adjacent grooves so that at least some of the wall portions of the grooves are geometrically shadowed during the subsequent sputtering step in which a superconductor is sputtered onto the substrate. In particular, a film of a suitable superconducting intermetallic compound having A-15 crystalline structure, such as Nb.sub.3 Ge, is thereupon sputtered onto the grooved substrate and deposits at the bottom of the grooves and at the surface portions of the substrate between grooves.
    Type: Grant
    Filed: August 20, 1976
    Date of Patent: July 18, 1978
    Assignee: Airco, Inc.
    Inventor: William G. Marancik
  • Patent number: 4090341
    Abstract: A method of treatment of equipment used in critical gas handling applications includes flowing designated gases through the equipment and packaging the equipment in an inert atmosphere for shipment.
    Type: Grant
    Filed: July 11, 1977
    Date of Patent: May 23, 1978
    Assignee: Airco, Inc.
    Inventor: Stephen George Wechter