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: 20240001288
    Abstract: Sulfur-containing compounds are removed from crude CO2 by conversion to elemental sulfur in a Claus process and subsequently by hydrogenation of the Claus tail gas to convert residual sulfur-containing compounds into H2S which, after cooling to knock out water and then compressing, is removed, together with any other sulfur-containing impurities, either by physical separation or by chemical reaction with a solid metal oxide to form solid metal sulfide with subsequent oxidative regeneration to produce purified CO2 and a recycle gas comprising at least one sulfur-containing compound which is recycled to the Claus process. Some H2S in the Claus tail gas may be removed initially by selective and/or non-selective amine absorption(s) in a tail gas treatment unit prior to removal of residual H2S and any other residual sulfur-containing impurities by the physical separation or the chemical reaction steps.
    Type: Application
    Filed: July 1, 2022
    Publication date: January 4, 2024
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Kamlesh Ghodasara, Paul Higginbotham, Jeffrey R. Hufton, Shubhra Jyoti Bhadra, Maulik R. Shelat
  • Publication number: 20230304733
    Abstract: A hydrogen feed stream comprising one or more impurities selected from the group consisting of nitrogen, argon, methane, carbon monoxide, carbon dioxide, oxygen, and water, is purified using a cryogenic temperature swing adsorption (CTSA) process with high overall recovery of hydrogen. The waste gas from regenerating the CTSA may be used to improve the performance of upstream hydrogen processing steps.
    Type: Application
    Filed: February 8, 2022
    Publication date: September 28, 2023
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Shubhra Jyoti Bhadra, Jeffrey R. Hufton, Timothy C. Golden, Aaron Raymond Scott, Kamlesh Ghodasara, Maulik R. Shelat, Garret C. Lau
  • Publication number: 20230249970
    Abstract: A hydrogen feed stream comprising one or more impurities selected from the group consisting of nitrogen, argon, methane, carbon monoxide, carbon dioxide, oxygen, and water, is contacted with liquid hydrogen in a cryogenic wash column (CWC) process that produces pure hydrogen with high overall recovery. The waste liquid stream leaving the CWC may be used to improve the performance of upstream hydrogen processing steps.
    Type: Application
    Filed: February 8, 2022
    Publication date: August 10, 2023
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Kamlesh Ghodasara, Maulik R. Shelat, Paul Higginbotham, Shubhra Jyoti Bhadra, Timothy C. Golden
  • Publication number: 20230070799
    Abstract: A method and system for decarbonization of a hydrocarbon conversion process such as steam methane reforming process for hydrogen production utilizing oxygen transport membrane reactors. The system employs catalyst-containing reforming reactors for converting natural gas into synthesis gas which is further treated in high temperature or medium temperature water gas shift reactors and fed to a hydrogen PSA to produce hydrogen product. The system further employs oxygen transport membrane reactors thermally coupled to reforming reactors and configured to oxy-combust about 90% to about 95% of combustibles in PSA tail gas that may be optionally mixed with natural gas. The oxy-combustion product stream leaving the oxygen transport membrane reactors contains about 90% of the carbon provided to the feed of the reforming reactor. The carbon dioxide in the oxy-combustion product stream can be recovered and further purified for utilization or geologic storage or liquefied to form a liquid carbon dioxide product.
    Type: Application
    Filed: December 18, 2020
    Publication date: March 9, 2023
    Inventors: Sean M. Kelly, Sadashiv M. Swami, Maulik R. Shelat, Ines C. Stuckert, Steven M. Brown, Shrikar Chakravarti, Juan Li, Digna Vora
  • Publication number: 20220290815
    Abstract: A cryogenic vaporization system and method are provided. A first heat exchanger heats a liquid cryogen via indirect heat exchange to output a cryogenic vapor at a first temperature. A second heat exchanger receives the cryogenic vapor at the first temperature. The second heat exchanger heats the cryogenic vapor via indirect heat exchange to a second temperature. The cryogenic vapor at the second temperature is recirculated to the first heat exchanger to heat the liquid cryogen and cool the recirculated cryogenic vapor to a third temperature. A third heat exchanger receives the cryogenic vapor at the third temperature. The third heat exchanger heats the cryogenic vapor to a fourth temperature. The third heat exchanger outputs the cryogenic vapor at the fourth temperature.
    Type: Application
    Filed: November 2, 2021
    Publication date: September 15, 2022
    Inventors: Hanfei Tuo, Chao Liang, Maulik R. Shelat, Sang Muk Kwark, Seth A. Potratz
  • Patent number: 11293671
    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: Grant
    Filed: July 7, 2020
    Date of Patent: April 5, 2022
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Neil M. Prosser, James R. Dray, Paul W. Belanger, Maulik R. Shelat
  • Publication number: 20200333050
    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: July 7, 2020
    Publication date: October 22, 2020
    Inventors: Neil M. Prosser, James R. Dray, Paul W. Belanger, Maulik R. Shelat
  • Patent number: 10808967
    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: Grant
    Filed: January 15, 2018
    Date of Patent: October 20, 2020
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Neil M. Prosser, James R. Dray, Paul W. Belanger, Maulik R. Shelat
  • Publication number: 20200080773
    Abstract: A cryogenic air separation unit that provides flexibility in the production of liquid products is disclosed. The present cryogenic air separation unit and associated operating methods involves the use of a dual nozzle arrangement for the main heat exchanger that allows a turbine air stream draw from the main heat exchanger at different temperatures to provide refrigeration to the cryogenic air separation unit which, in turn, enables different production modes for the various liquid products.
    Type: Application
    Filed: September 7, 2018
    Publication date: March 12, 2020
    Inventors: Zhengrong Xu, Maulik R. Shelat, Nick J. Degenstein, Hanfei Tuo
  • Patent number: 10520265
    Abstract: A method for creating a coating onto an inner diameter of conduit, whereby an injection nozzle is moved in a forward direction until its tip is aligned with the end of the conduit. Slurry is pumped from a reservoir into the injection nozzle and then is discharged through the tip of the injection nozzle. The slurry flows, distributes and spreads onto the surface of the conduit. The conduit is rotated and the nozzle is retracted as slurry continues to discharge from the nozzle to coat the remainder of the conduit.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: December 31, 2019
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Sang Muk Kwark, Zigui Lu, David P. Potempa, Maulik R. Shelat
  • Patent number: 10408536
    Abstract: A system and method for neon recovery in a double column or triple column air separation unit is provided. The neon recovery system comprises a non-condensable stripping column configured to produce a liquid nitrogen-rich liquid column bottoms and a non-condensable gas containing overhead and one or more condensing units arranged to produce a crude neon vapor stream that contains greater than about 50% mole fraction of neon with the overall neon recovery exceeding 95%. In addition, there is minimal liquid nitrogen consumption and since much of the liquid nitrogen is recycled back to the lower pressure column of the air separation unit, there is minimal impact on the recovery of other products from the air separation unit.
    Type: Grant
    Filed: September 5, 2017
    Date of Patent: September 10, 2019
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Maulik R. Shelat, Hanfei Tuo, Nick J. Degenstein, James R. Dray
  • Patent number: 10337792
    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 or vapor 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: February 8, 2016
    Date of Patent: July 2, 2019
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Neil M. Prosser, Karl K. Kibler, Maulik R. Shelat
  • Patent number: 10295254
    Abstract: A system and method for recovery of rare gases such as neon, helium, xenon, and krypton in an air separation unit is provided. The rare gas recovery system comprises a non-condensable stripping column linked in a heat transfer relationship with a xenon-krypton column via an auxiliary condenser-reboiler. The non-condensable stripping column produces a rare gas containing overhead that is directed to the auxiliary condenser-reboiler where most of the neon is captured in a non-condensable vent stream that is further processed to produce a crude neon vapor stream that contains greater than about 50% mole fraction of neon with the overall neon recovery exceeding 95%. The xenon-krypton column further receives two streams of liquid oxygen from the lower pressure column and the rare gas containing overhead from the non-condensable stripping column and produces a crude xenon and krypton liquid stream and an oxygen-rich overhead.
    Type: Grant
    Filed: September 5, 2017
    Date of Patent: May 21, 2019
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Vijayaraghavan S. Chakravarthy, Hanfei Tuo, Maulik R. Shelat, James R. Dray, Nick J. Degenstein
  • Patent number: 10247471
    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: July 11, 2018
    Date of Patent: April 2, 2019
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: James R. Handley, Brian S. Powell, Henry E. Howard, Vijayaraghavan S. Chakravarthy, Maulik R. Shelat, Steven R. Falta
  • Publication number: 20190072326
    Abstract: A system and method for recovery of rare gases such as neon, helium, xenon, and krypton in an air separation unit is provided. The rare gas recovery system comprises a non-condensable stripping column linked in a heat transfer relationship with a xenon-krypton column via an auxiliary condenser-reboiler. The non-condensable stripping column produces a rare gas containing overhead that is directed to the auxiliary condenser-reboiler where most of the neon is captured in a non-condensable vent stream that is further processed to produce a crude neon vapor stream that contains greater than about 50% mole fraction of neon with the overall neon recovery exceeding 95%. The xenon-krypton column further receives two streams of liquid oxygen from the lower pressure column and the rare gas containing overhead from the non-condensable stripping column and produces a crude xenon and krypton liquid stream and an oxygen-rich overhead.
    Type: Application
    Filed: September 5, 2017
    Publication date: March 7, 2019
    Inventors: Vijayaraghavan S. Chakravarthy, Hanfei Tuo, Maulik R. Shelat, James R. Dray, Nick J. Degenstein
  • Publication number: 20190072325
    Abstract: A system and method for neon recovery in a double column or triple column air separation unit is provided. The neon recovery system comprises a non-condensable stripping column configured to produce a liquid nitrogen-rich liquid column bottoms and a non-condensable gas containing overhead and one or more condensing units arranged to produce a crude neon vapor stream that contains greater than about 50% mole fraction of neon with the overall neon recovery exceeding 95%. In addition, there is minimal liquid nitrogen consumption and since much of the liquid nitrogen is recycled back to the lower pressure column of the air separation unit, there is minimal impact on the recovery of other products from the air separation unit.
    Type: Application
    Filed: September 5, 2017
    Publication date: March 7, 2019
    Inventors: Maulik R. Shelat, Hanfei Tuo, Nick J. Degenstein, James R. Dray
  • Patent number: 10221970
    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: June 21, 2018
    Date of Patent: March 5, 2019
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Zigui Lu, Sang Muk Kwark, Joseph M. Corpus, Jonathan A. Lane, David P. Potempa, Maulik R. Shelat
  • Patent number: 10190819
    Abstract: An argon reflux condensation system and method in which a plurality of once-through heat exchangers 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 plant where the crude liquid oxygen is in a liquid state and in proportion to the size of the once-through heat exchangers. Feed stream flow rate to the argon column is controlled in response to air flow rate to the plant and product flow rate is controlled in response to the feed stream flow rate to the argon column.
    Type: Grant
    Filed: July 11, 2018
    Date of Patent: January 29, 2019
    Assignee: PRAXAIR TECHNOLOGY, INC.
    Inventors: Steven R. Falta, Brian S. Powell, Henry E. Howard, Vijayaraghavan S. Chakravarthy, Maulik R. Shelat
  • Publication number: 20180328655
    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: Application
    Filed: July 11, 2018
    Publication date: November 15, 2018
    Inventors: James R. Handley, Brian S. Powell, Henry E. Howard, Vijayaraghavan S. Chakravarthy, Maulik R. Shelat, Steven R. Falta
  • Publication number: 20180320962
    Abstract: An argon reflux condensation system and method in which a plurality of once-through heat exchangers 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 plant where the crude liquid oxygen is in a liquid state and in proportion to the size of the once-through heat exchangers. Feed stream flow rate to the argon column is controlled in response to air flow rate to the plant and product flow rate is controlled in response to the feed stream flow rate to the argon column.
    Type: Application
    Filed: July 11, 2018
    Publication date: November 8, 2018
    Inventors: Steven R. Falta, Brian S. Powell, Henry E. Howard, Vijayaraghavan S. Chakravarthy, Maulik R. Shelat