Patents by Inventor Douglas L. Bennett

Douglas L. Bennett 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: 5305610
    Abstract: The present invention is a separation process for atmospheric gases. In the process, an atmospheric gas stream, for example air, is compressed and may be partly condensed prior to introduction into a vortex tube air separator. The performance of the tube separation can be upgraded, i.e. by improving the concentration and/or purity of the main oxygen stream, by enhancing the separator efficiency of the vortex tube (VT) apparatus. One approach is by selectively refrigerating the cold end of the tube with partial recycle of nitrogen gas waste stream, effecting a rectification section. Another approach is to increase the heat transfer between the outlet gas stream and the liquid film flowing along the curvilinear periphery of the separator means, by mechanical innovations in its configuration.
    Type: Grant
    Filed: August 28, 1990
    Date of Patent: April 26, 1994
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, Keith A. Ludwig, Robert F. Weimer
  • Patent number: 5122174
    Abstract: The present invention relates to a boiling process in a downflow heat exchanger and the heat exchanger itself with liquid distribution enhancing features which improve performance and allow safe and efficient operation. Performance enhancing features include a partially flooded hardway distribution region with a liquid volume fraction greater than about 0.25 and preferably greater than 0.5, adjusting the heat transfer surface area to maintain a liquid film Reynolds number above 20 and, preferably, above 50 yet less than 1000, preferably less than 300, for at least 75% of the reboiler surface, and, optionally, intermediate feeding of liquid at various intervals along the length of the heat exchanger to obtain more uniform values of liquid film Reynolds numbers and intermediate redistribution.
    Type: Grant
    Filed: March 1, 1991
    Date of Patent: June 16, 1992
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Swaminathan Sunder, Douglas L. Bennett, Donn M. Herron, Keith A. Ludwig, Edwin C. Rogusky
  • Patent number: 4981111
    Abstract: A circulating fluidized bed combustion reactor and a process for combusting a solid hydrocarbon fuel in the same wherein fly ash recycling is utilized to regulate heat transfer and to minimize erosion of reactor operating components.
    Type: Grant
    Filed: November 28, 1989
    Date of Patent: January 1, 1991
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, David W. Studer
  • Patent number: 4871382
    Abstract: The present invention relates to an improvement to a cryogenic air separation process having an argon sidearm column. The improvement to the process for maximizing argon recovery comprises effectuating the intimate contact of the liquid phase stream and the vapor phase stream in the low pressure column and the argon sidearm column of an integrated multi-column, e.g. three column, cryogenic distillation system by utilizing a structured or ordered packing.
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: October 3, 1989
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Robert M. Thorogood, Douglas L. Bennett, Rodney J. Allam, Alan L. Prentice, Bruce K. Dawson
  • Patent number: 4836836
    Abstract: The present invention relates to improvements to a process and apparatus for the cryogenic distillation of mixtures, which comprise oxygen, nitrogen and argon, e.g. air. The improvement comprises effectuating intimate contact of the liquid and vapor phase streams utilizing a structured packing to effectuate the intimate contact in at least those regions of the distillation column system where argon concentration is within the range from about 0.6 to about 75 volume percent, and operating the process such that the densimetric superficial gas velocity in those regions is at least 0.06 feet per second. The present invention also relates to a method for improving a cryogenic distillation apparatus having at least one distillation column for the separation of mixtures containing oxygen and argon, comprising the step of replacing the distillation trays with a structured packing in at least those regions of the distillation column system where the concentration of argon is in the range from about 0.
    Type: Grant
    Filed: December 14, 1987
    Date of Patent: June 6, 1989
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, Keith A. Ludwig, George S. Witmer, Charles M. Woods
  • Patent number: 4813988
    Abstract: This invention relates to a process for the cryogenic separation of oxygen-containing mixtures to produce an enriched product whereby oxygen concentrations greater than 21% by volume are achieved in the process via passing streams of liquid and vapor countercurrently through a mass transfer zone which contains packing elements fabricated from a material having a thickness of less than about 1 millimeter, having a copper concentration of at least about 30% by weight and a heat of combustion of less than 1.0 Kcal/g, thereby avoiding the risk of flammability.
    Type: Grant
    Filed: May 23, 1988
    Date of Patent: March 21, 1989
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, Keith A. Ludwig, Andrew J. Patrylak, John Zabrenski
  • Patent number: 4700771
    Abstract: The invention relates to a process and apparatus for boiling flowing liquids such as liquefied gases in a heat exchanger in which a circulating flow is occurring, such as in reboiler-condensers in air separation and similar cryogenic plants or other applications where a high efficiency for boiling heat transfer is beneficial. The important feature of the process and apparatus is the use of two sequential heat transfer zones having different pressure drop and heat transfer characteristics in the same boiling channel, the first zone having an overall high-convective-heat-transfer characteristic and an overall higher pressure drop characteristic and comprising a plurality of sub-zones, each sub-zone sequentially having a lower pressure drop than the previous sub-zone and the second zone having a lower pressure drop and an enhanced nucleate boiling heat transfer characteristic.
    Type: Grant
    Filed: January 13, 1987
    Date of Patent: October 20, 1987
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, Keith A. Ludwig, Alexander Schwarz
  • Patent number: 4653572
    Abstract: The invention relates to a process and apparatus for boiling flowing liquid such as liquefied gases in a heat exchanger in which a circulating flow is occuring, such as in reboiler-condensers in air separation and similar cryogenic plants or other applications where a high efficiency for boiling heat transfer is beneficial. The important feature of the process and apparatus is the use of two sequential heat transfer zones having different pressure drop and heat transfer characteristics in the same boiling channel, the first zone having a higher pressure drop and high convective heat transfer characteristic and the second zone having a lower pressure drop and an enhanced nucleate boiling heat transfer characteristic.
    Type: Grant
    Filed: March 11, 1986
    Date of Patent: March 31, 1987
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, Alexander Schwarz, Robert M. Thorogood
  • Patent number: 4510023
    Abstract: This invention relates to a distillation system for effecting separation of a multicomponent fluid and to an improved bubble-cap design which can accommodate very wide ranges of vapor and liquid loadings. A portion of the tray is provided with bubble caps having first and second slot openings with the second slot opening at an elevation higher than the first opening.
    Type: Grant
    Filed: June 17, 1983
    Date of Patent: April 9, 1985
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, Thomas J. Edwards, Howard C. Rowles
  • Patent number: 4411756
    Abstract: An ozone generator is set forth wherein the production of ozone is increased by the more efficient cooling of the generator electrodes and therefore the discharge gap where the ozone forms. The cooling is effected by the use of a boiling coolant fluid which has a high heat transfer capacity. Additionally the electrode structure is made more rigid for increased life in the presence of boiling cooling fluid. A method of ozone preparation is also set forth. Alternately cooling can be enhanced by the introduction of a gas into the coolant to enhance coolant turbulence without boiling the coolant.
    Type: Grant
    Filed: March 31, 1983
    Date of Patent: October 25, 1983
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, Donald C. Amoss
  • Patent number: D322353
    Type: Grant
    Filed: September 22, 1988
    Date of Patent: December 17, 1991
    Inventor: Douglas L. Bennett
  • Patent number: RE34038
    Abstract: The present invention relates to improvements to a process and apparatus for the cryogenic distillation of mixtures, which comprise oxygen, nitrogen and argon, e.g. air. The improvement comprises effectuating intimate contact of the liquid and vapor phase streams utilizing a structured packing to effectuate the intimate contact in at least .[.those.]. .Iadd.one of the .Iaddend.regions of the distillation column system where argon concentration is within the range from about 0.6 to about 75 volume percent.[.,.]. and .[.operating the process such that.]. the densimetric superficial gas velocity .[.in those regions.]. is at least 0.06 feet per second. .[.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: August 25, 1992
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Douglas L. Bennett, Keith A. Ludwig, George S. Witmer, Charles M. Woods