Patents by Inventor Maulik R. Shelat

Maulik R. Shelat 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).

  • Publication number: 20180299035
    Abstract: A porous metallic coating is provided. The coating is characterized by a combination of optimized properties that improve coating performance, as measured by heat transfer efficiency. The porous coating has optimal ranges for properties such as porosity, particle size and thickness, and has particular applicability in boiling heat transfer applications as part of an air separations unit. The porous coatings are derived from slurry-based formulations that include a mixture of metallic particles, a binder and a solvent.
    Type: Application
    Filed: June 21, 2018
    Publication date: October 18, 2018
    Inventors: Zigui Lu, Sang Muk Kwark, Joseph M. Corpus, Jonathan A. Lane, David P. Potempa, Maulik R. Shelat
  • Patent number: 10082333
    Abstract: An argon reflux condensation system and method in which a plurality of once-through condensers are connected to an argon column of an air separation plant to condense argon-rich vapor streams for production of reflux to the argon column. Condensation of the argon-rich vapor streams is brought about through indirect heat exchange with crude liquid oxygen streams that partially vaporize and are introduced into a lower pressure column of the plant for further refinement. The flow rate of the crude liquid oxygen streams are sensed and controlled at locations in the air separation plant where the crude liquid oxygen is in a liquid state and in proportion to the size of the once-through heat exchangers. Prior to flowing into the once-through condensers, the partially vaporized crude oxygen stream enters a phase separator which separates the crude oxygen vapor from the crude liquid oxygen.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: September 25, 2018
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: James R. Handley, Brian S. Powell, Henry E. Howard, Vijayaraghavan S. Chakravarthy, Maulik R. Shelat, Steven R. Falta
  • Patent number: 10048004
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting.
    Type: Grant
    Filed: October 5, 2016
    Date of Patent: August 14, 2018
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Maulik R. Shelat, Vijayaraghavan S. Chakravarthy, Sang Muk Kwark
  • Patent number: 10047880
    Abstract: A porous metallic coating is provided. The coating is characterized by a combination of optimized properties that improve coating performance, as measured by heat transfer efficiency. The porous coating has optimal ranges for properties such as porosity, particle size and thickness, and has particular applicability in boiling heat transfer applications as part of an air separations unit. The porous coatings are derived from slurry-based formulations that include a mixture of metallic particles, a binder and a solvent.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: August 14, 2018
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Zigui Lu, Sang Muk Kwark, Joseph M. Corpus, Jonathan A. Lane, David P. Potempa, Maulik R. Shelat
  • Publication number: 20180202690
    Abstract: Closed-loop refrigeration cycles for liquid oxygen densification are disclosed. The disclosed refrigeration cycles may be turbine-based refrigeration cycles or a Joule-Thompson (JT) expansion valve based refrigeration cycles and include a refrigerant or working fluid comprising a mixture of neon or helium together with nitrogen and/or oxygen.
    Type: Application
    Filed: January 15, 2018
    Publication date: July 19, 2018
    Inventors: Neil M. Prosser, James R. Dray, Paul W. Belanger, Maulik R. Shelat
  • Patent number: 10012439
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting.
    Type: Grant
    Filed: October 5, 2016
    Date of Patent: July 3, 2018
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Maulik R. Shelat, Vijayaraghavan S. Chakravarthy, Sang Muk Kwark
  • Patent number: 9920988
    Abstract: A method and main heat exchange system for use in a cryogenic air separation plant in which down-flow and thermosiphon heat exchangers are employed to partially vaporize an oxygen-rich liquid produced in a lower pressure column and to condense the nitrogen-rich vapor in a higher pressure column. A greater proportion of the oxygen-rich liquid can be partially vaporized in the down-flow heat exchangers than in the thermosiphon heat exchangers and the nitrogen-rich vapor condensed in the thermosiphon heat exchangers can have a higher oxygen content than the nitrogen-rich vapor condensed in the down-flow heat exchangers. This allows the higher pressure column to operate at a lower pressure than would otherwise be possible. A central conduit can extend from the higher pressure column into the lower pressure column to introduce the nitrogen-rich vapor into at least the down-flow heat exchangers for purposes of reducing pressure drop and column height.
    Type: Grant
    Filed: August 22, 2016
    Date of Patent: March 20, 2018
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Vijayaraghavan S. Chakravarthy, Michael J. Lockett, Dante P. Bonaquist, Maulik R. Shelat, Karl K. Kibler
  • Patent number: 9664442
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting by means of a venting apparatus having a plurality of perforated tubes.
    Type: Grant
    Filed: May 12, 2016
    Date of Patent: May 30, 2017
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Hanfei Tuo, Karl K. Kibler, Maulik R. Shelat
  • Publication number: 20170108296
    Abstract: A method for creating a coating onto a conduit is provided. The method includes rotating the conduit while injecting a controlled amount of slurry onto the surface of an inner diameter of the conduit through a nozzle that is retracted from out of the conduit at a controlled speed. The method offers improved reproducibility and repeatability of coating properties in comparison to conventional coating methods.
    Type: Application
    Filed: October 15, 2015
    Publication date: April 20, 2017
    Inventors: SANG MUK KWARK, ZIGUI LU, DAVID P. POTEMPA, MAULIK R. SHELAT
  • Publication number: 20170108148
    Abstract: A porous metallic coating is provided. The coating is characterized by a combination of optimized properties that improve coating performance, as measured by heat transfer efficiency. The porous coating has optimal ranges for properties such as porosity, particle size and thickness, and has particular applicability in boiling heat transfer applications as part of an air separations unit. The porous coatings are derived from slurry-based formulations that include a mixture of metallic particles, a binder and a solvent.
    Type: Application
    Filed: October 15, 2015
    Publication date: April 20, 2017
    Inventors: ZIGUI LU, SANG MUK KWARK, JOSEPH M. CORPUS, JONATHAN A. LANE, DAVID P. POTEMPA, MAULIK R. SHELAT
  • Patent number: 9599396
    Abstract: A system and method for producing argon that uses a higher pressure column, a lower pressure column, and an argon column collectively configured to produce nitrogen, oxygen and argon products through the cryogenic separation of air. The present system and method also employs a once through argon condensing assembly that is disposed entirely within the lower pressure column that is configured to condense an argon rich vapor stream from the argon column against the oxygen-enriched liquid from the higher pressure column to produce an argon liquid product. The control system is configured for optimizing the production of argon product by ensuring an even flow split of the oxygen-enriched liquid is distributed to the argon condenser cores and by adjusting the flow rate of the argon removed from the argon condensing assembly to maintain the liquid/vapor balance in the argon condensing assembly within appropriate limits.
    Type: Grant
    Filed: January 5, 2016
    Date of Patent: March 21, 2017
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Karl K. Kibler, Maulik R. Shelat
  • Publication number: 20170023297
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting.
    Type: Application
    Filed: October 5, 2016
    Publication date: January 26, 2017
    Inventors: Maulik R. Shelat, Vijayaraghavan S. Chakravarthy, Sang Muk Kwark
  • Publication number: 20170023298
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting.
    Type: Application
    Filed: October 5, 2016
    Publication date: January 26, 2017
    Inventors: Maulik R. Shelat, Vijayaraghavan S. Chakravarthy, Sang Muk Kwark
  • Publication number: 20160356546
    Abstract: A method and main heat exchange system for use in a cryogenic air separation plant in which down-flow and thermosiphon heat exchangers are employed to partially vaporize an oxygen-rich liquid produced in a lower pressure column and to condense the nitrogen-rich vapor in a higher pressure column. A greater proportion of the oxygen-rich liquid can be partially vaporized in the down-flow heat exchangers than in the thermosiphon heat exchangers and the nitrogen-rich vapor condensed in the thermosiphon heat exchangers can have a higher oxygen content than the nitrogen-rich vapor condensed in the down-flow heat exchangers. This allows the higher pressure column to operate at a lower pressure than would otherwise be possible. A central conduit can extend from the higher pressure column into the lower pressure column to introduce the nitrogen-rich vapor into at least the down-flow heat exchangers for purposes of reducing pressure drop and column height.
    Type: Application
    Filed: August 22, 2016
    Publication date: December 8, 2016
    Inventors: Vijayaraghavan S. Chakravarthy, Michael J. Lockett, Dante P. Bonaquist, Maulik R. Shelat, Karl K. Kibler
  • Patent number: 9488408
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting.
    Type: Grant
    Filed: January 29, 2014
    Date of Patent: November 8, 2016
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Maulik R. Shelat, Vijayaraghavan S. Chakravarthy, Sang Muk Kwark
  • Patent number: 9488407
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting by means of a venting apparatus having a plurality of perforated tubes.
    Type: Grant
    Filed: May 12, 2016
    Date of Patent: November 8, 2016
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Hanfei Tuo, Karl K. Kibler, Maulik R. Shelat
  • Patent number: 9453674
    Abstract: A method and main heat exchange system for use in a cryogenic air separation plant in which down-flow and thermosiphon heat exchangers are employed to partially vaporize an oxygen-rich liquid produced in a lower pressure column and to condense the nitrogen-rich vapor in a higher pressure column. A greater proportion of the oxygen-rich liquid can be partially vaporized in the down-flow heat exchangers than in the thermosiphon heat exchangers and the nitrogen-rich vapor condensed in the thermosiphon heat exchangers can have a higher oxygen content than the nitrogen-rich vapor condensed in the down-flow heat exchangers. This allows the higher pressure column to operate at a lower pressure than would otherwise be possible. A central conduit can extend from the higher pressure column into the lower pressure column to introduce the nitrogen-rich vapor into at least the down-flow heat exchangers for purposes of reducing pressure drop and column height.
    Type: Grant
    Filed: June 5, 2014
    Date of Patent: September 27, 2016
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Vijayaraghavan S. Chakravarthy, Michael J. Lockett, Dante P. Bonaquist, Maulik R. Shelat, Karl K. Kibler
  • Publication number: 20160258678
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting by means of a venting apparatus having a plurality of perforated tubes.
    Type: Application
    Filed: May 12, 2016
    Publication date: September 8, 2016
    Inventors: Hanfei Tuo, Karl K. Kibler, Maulik R. Shelat
  • Publication number: 20160258677
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting by means of a venting apparatus having a plurality of perforated tubes.
    Type: Application
    Filed: May 12, 2016
    Publication date: September 8, 2016
    Inventors: Hanfei Tuo, Karl K. Kibler, Maulik R. Shelat
  • Patent number: 9366476
    Abstract: A system and method for the concurrent condensation of a nitrogen-rich vapor and vaporization of an oxygen-rich liquid in a distillation column based air separation unit is provided. The disclosed system includes a condenser-reboiler heat exchanger located between a lower pressure column and a higher pressure column and configured to condense a nitrogen-rich vapor from the higher pressure column and partially vaporize an oxygen-rich liquid from the lower pressure column. Within the condenser-reboiler heat exchanger, the nitrogen-rich vapor flows in an upward direction such that any non-condensables present in the nitrogen-rich vapor will accumulate proximate the upper portion or top of the condenser-reboiler modules where they can be easily removed through venting by means of a venting apparatus having a plurality of perforated tubes.
    Type: Grant
    Filed: November 20, 2015
    Date of Patent: June 14, 2016
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Hanfei Tuo, Karl K. Kibler, Maulik R. Shelat