Patents by Inventor Gowri Krishnamurthy

Gowri Krishnamurthy 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: 20240001282
    Abstract: A method and system for purifying a carbon dioxide feed stream in which the carbon dioxide feed stream is cooled and partially condensed to remove water upstream of an adsorber to produce a dry carbon dioxide stream. The dry carbon dioxide stream is further cooled and partially condensed in a carbon dioxide purification unit to form a carbon dioxide product stream. Excess refrigeration duty from the carbon dioxide purification unit is used to cool the carbon dioxide feed stream.
    Type: Application
    Filed: July 1, 2022
    Publication date: January 4, 2024
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Paul Higginbotham, Dingjun Wu, Gowri Krishnamurthy, Todd M. Moyle, Michelle Roaf, Mozhgan Alimohammadi Zanjani
  • Publication number: 20240001283
    Abstract: A method for capturing carbon dioxide from a carbon dioxide feed stream in which the carbon dioxide feed stream is dehydrated, cooled, and partially condensed. The partially condensed carbon dioxide stream is separated to form the carbon dioxide product stream. The carbon dioxide feed stream is produced by combusting a fuel stream with an oxygen-enriched gas stream with less than 92% purity.
    Type: Application
    Filed: July 1, 2022
    Publication date: January 4, 2024
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Todd M. Moyle, Paul Higginbotham, Dingjun Wu, Gowri Krishnamurthy, Michelle Roaf, Christer Haugland
  • Patent number: 11624555
    Abstract: A system and method for increasing the efficiency of natural gas liquefaction processes by using a hybrid cooling system and method. More specifically, a system and method for converting a transcritical precooling refrigeration process to a subcritical process. In one embodiment, the refrigerant is cooled to sub-critical temperature using an economizer. In another embodiment, the refrigerant is cooled to a sub-critical temperature using an auxiliary heat exchanger. Optionally, the economizer or auxiliary heat exchanger can be bypassed when ambient temperatures are sufficiently low to cool the refrigerant to a sub-critical temperature. In another embodiment, the refrigerant is isentropically expanded.
    Type: Grant
    Filed: March 23, 2020
    Date of Patent: April 11, 2023
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Mark Julian Roberts
  • Publication number: 20230087673
    Abstract: A method and apparatus for purifying air via a pre-purification unit (PPU) of an air separation unit (ASU) system can include passing air through a first adsorber of the PPU to purify the air for operation of the ASU system while it is at or below a first pre-selected operational capacity. In response to the operational capacity of the ASU system needing to be increased to a level above the first pre-selected operational capacity threshold, a second adsorber can be brought on-line in parallel with the first adsorber or in series with the first adsorber to provide improved purification capacity to account for the increased demand for purification capacity resulting from the increased operational capacity of the ASU system. This second adsorber can be different from the first adsorber (e.g. different in size, adsorption capacity for impurities within air, and/or configuration, etc.).
    Type: Application
    Filed: September 23, 2021
    Publication date: March 23, 2023
    Applicant: Air Products and Chemicals, Inc.
    Inventors: GOWRI KRISHNAMURTHY, DINGJUN WU, NASIM UL HASSAN MALIK
  • Patent number: 11596895
    Abstract: A radial adsorber can be configured to facilitate utilization of different layers of material. The radial adsorber, system using at least one radial adsorber, and methods of utilizing embodiments of the radial adsorber can help permit improved efficient operation of fluid purification processing while also being configured to minimize, if not fully avoid, being susceptible to the effect of fluidization.
    Type: Grant
    Filed: July 17, 2020
    Date of Patent: March 7, 2023
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Nasim Ul Hassan Malik, Edward Landis Weist, Jr., King Wai Hung
  • Publication number: 20230027070
    Abstract: A method of purifying air via a pre-purification unit (PPU) of an air separation unit (ASU) system having a pre-PPU chiller that is upstream of the PPU to cool compressed air before the compressed air is fed to the PPU can include passing air through an adsorber of the PPU to pass the air through a bed of adsorbent material within a vessel of the adsorber. In response to the pre-PPU chiller being determined to have an issue resulting in the pre-PPU chiller being tripped or requiring the pre-PPU chiller to be taken off-line, continuing to operate the ASU system at a full capacity even though nitrous oxide (N2O) within the air output from the PPU exceeds a first pre-selected threshold and is below a second pre-selected threshold associated with carbon dioxide (CO2) breakthrough. An ASU and a PPU can be designed to implement an embodiment of the method.
    Type: Application
    Filed: July 21, 2021
    Publication date: January 26, 2023
    Applicant: Air Products and Chemicals, Inc.
    Inventors: NASIM UL HASSAN MALIK, GOWRI KRISHNAMURTHY, DINGJUN WU
  • Patent number: 11439946
    Abstract: An adsorbent vessel for removing contaminants from a feed gas upstream from a cryogenic distillation process using pressure swing adsorption, temperature swing adsorption, or thermal-pressure swing adsorption. The adsorbent vessel having an adsorbent bed comprised of multiple layers of adsorbent material, including two layers of adsorbent material that selective adsorbs carbon dioxide. Each of the two layers is formed from an adsorbent material having a different capacity for adsorbing carbon dioxide.
    Type: Grant
    Filed: September 30, 2020
    Date of Patent: September 13, 2022
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Nasim Ul Hassan Malik, King Wai Hung, Gowri Krishnamurthy, William T. Kleinberg, Garrett C. Lau, Edward Landis Weist, Jr.
  • Publication number: 20220099367
    Abstract: A chiller can be configured as a chiller for a gasification system or other type of system or plant. In some embodiments, the chiller can be configured to utilize a single heat source, such as low grade waste heat in the form of hot water, and/or low pressure steam to drive one or more absorption-based chillers to cool inlet air to one or more adsorbers of a pre-purification unit (PPU). In the event of the detection of an undesired impurity spike (e.g. carbon dioxide spike, etc.) an additional amount of heat source can be withdrawn from the gasification system to increase the level of cooling the absorption chiller can provide to improve the removal of impurities. An automated control loop can be utilized in some embodiments. The control loop can be configured to check for an impurity concentration and adjust operations accordingly.
    Type: Application
    Filed: September 29, 2020
    Publication date: March 31, 2022
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Nasim Ul Hassan Malik, Qiao Zhao
  • Publication number: 20220096993
    Abstract: An adsorbent vessel for removing contaminants from a feed gas upstream from a cryogenic distillation process using pressure swing adsorption, temperature swing adsorption, or thermal-pressure swing adsorption. The adsorbent vessel having an adsorbent bed comprised of multiple layers of adsorbent material, including two layers of adsorbent material that selective adsorbs carbon dioxide. Each of the two layers is formed from an adsorbent material having a different capacity for adsorbing carbon dioxide.
    Type: Application
    Filed: September 30, 2020
    Publication date: March 31, 2022
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Nasim Ul Hassan Malik, King Wai Hung, Gowri Krishnamurthy, William T. Kleinberg, Garrett C. Lau, Edward Landis Weist, JR.
  • Publication number: 20220016565
    Abstract: A radial adsorber can be configured to facilitate utilization of different layers of material. The radial adsorber, system using at least one radial adsorber, and methods of utilizing embodiments of the radial adsorber can help permit improved efficient operation of fluid purification processing while also being configured to minimize, if not fully avoid, being susceptible to the effect of fluidization.
    Type: Application
    Filed: July 17, 2020
    Publication date: January 20, 2022
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Nasim Ul Hassan Malik, Edward Landis Weist, JR., King Wai Hung
  • Patent number: 10866022
    Abstract: Described herein are methods and systems for the liquefaction of a natural gas stream using a refrigerant comprising methane or a mixture of methane and nitrogen. The methods and systems use a refrigeration circuit and cycle that employs one or more turbo-expanders to expand one or more streams of gaseous refrigerant to provide one or more streams of at least predominantly gaseous refrigerant that are used to provide refrigeration for liquefying and/or precooling the natural gas, and a J-T valve to expand down to a lower pressure a stream of liquid or two-phase refrigerant to provide a vaporizing stream of refrigerant that provides refrigeration for sub-cooling.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: December 15, 2020
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Mark Julian Roberts
  • Patent number: 10852059
    Abstract: Systems and methods described for increasing capacity and efficiency of natural gas liquefaction processes having a mixed refrigerant precooling system with multiple pressure levels comprising cooling the compressed mixed refrigerant stream and separating the cooled compressed mixed refrigerant stream into a vapor and liquid portion. The liquid portion provides refrigeration duty to a first precooling heat exchanger. The vapor portion is further compressed, cooled, and condensed, and used to provide refrigeration duty to a second precooling heat exchanger. A flash gas separated from the liquefied natural gas is warmed and combined with the natural gas feed stream.
    Type: Grant
    Filed: September 28, 2017
    Date of Patent: December 1, 2020
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Mark Julian Roberts, Adam Adrian Brostow
  • Patent number: 10788261
    Abstract: Described herein are methods and systems for the liquefaction of a natural gas feed stream using a refrigerant comprising methane. The methods and systems use a refrigeration circuit and cycle that employs two or more turbo-expanders to expand two or more streams of gaseous refrigerant down to different pressures to provide cold streams of at least predominantly gaseous refrigerant at different pressures that are used to provide refrigeration for precooling and liquefying the natural gas. The resulting liquefied natural gas stream is then flashed to produce an LNG product and a flash gas, the flash gas being recycled to the natural gas feed stream.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: September 29, 2020
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Mark Julian Roberts
  • Patent number: 10788260
    Abstract: Described herein is a method of removing refrigerant from a natural gas liquefaction system in which vaporized mixed refrigerant is withdrawn from the closed-loop refrigeration circuit and introduced into a distillation column so as to be separated into an overhead vapor enriched in methane and a bottoms liquid enriched in heavier components. Overhead vapor is withdrawn from the distillation column to form a methane enriched stream that is removed from the liquefaction system, and bottoms liquid is reintroduced from the distillation column into the closed-loop refrigeration circuit. Also described are methods of altering the rate of production in a natural gas liquefaction system in which refrigerant is removed as described above, and a natural gas liquefaction systems in which such methods can be carried out.
    Type: Grant
    Filed: August 8, 2017
    Date of Patent: September 29, 2020
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Brian Keith Johnston, Gowri Krishnamurthy, Mark Julian Roberts
  • Patent number: 10767922
    Abstract: A method and apparatus for liquefying a natural gas feed stream and removing nitrogen therefrom to produce a nitrogen-depleted LNG product, in which a natural gas feed stream is fed into the warm end of a main heat exchanger, cooled and at least partially liquefied, withdrawn from an intermediate location of the main heat exchanger and separated to form a nitrogen-enriched natural gas vapor stream and a nitrogen-depleted natural gas liquid stream, the liquid and vapor streams being reintroduced into an intermediate location of the main heat exchanger and further cooled in parallel to form a first LNG stream and a first at least partially liquefied nitrogen-enriched natural gas stream, respectively.
    Type: Grant
    Filed: June 19, 2017
    Date of Patent: September 8, 2020
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Fei Chen, Yang Liu, Gowri Krishnamurthy, Christopher Michael Ott, Mark Julian Roberts
  • Patent number: 10753676
    Abstract: Systems and methods described for increasing capacity and efficiency of natural gas liquefaction processes having a mixed refrigerant precooling system with multiple pressure levels comprising cooling the compressed mixed refrigerant stream and separating the cooled compressed mixed refrigerant stream into a vapor and liquid portion. The liquid portion provides refrigeration duty to a first precooling heat exchanger. The vapor portion is further compressed, cooled, and condensed, and used to provide refrigeration duty to a second precooling heat exchanger. A flash gas separated from the liquefied natural gas is warmed and combined with the natural gas feed stream.
    Type: Grant
    Filed: September 28, 2017
    Date of Patent: August 25, 2020
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Mark Julian Roberts, Adam Adrian Brostow
  • Publication number: 20200217585
    Abstract: A system and method for increasing the efficiency of natural gas liquefaction processes by using a hybrid cooling system and method. More specifically, a system and method for converting a transcritical precooling refrigeration process to a subcritical process. In one embodiment, the refrigerant is cooled to sub-critical temperature using an economizer. In another embodiment, the refrigerant is cooled to a sub-critical temperature using an auxiliary heat exchanger. Optionally, the economizer or auxiliary heat exchanger can be bypassed when ambient temperatures are sufficiently low to cool the refrigerant to a sub-critical temperature. In another embodiment, the refrigerant is isentropically expanded.
    Type: Application
    Filed: March 23, 2020
    Publication date: July 9, 2020
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Mark Julian Roberts
  • Patent number: 10663220
    Abstract: Systems and methods described for increasing capacity and efficiency of natural gas liquefaction processes having a mixed refrigerant precooling system with multiple pressure levels comprising cooling the compressed mixed refrigerant stream and separating the cooled compressed mixed refrigerant stream into a vapor and liquid portion. The liquid portion provides refrigeration duty to a first precooling heat exchanger. The vapor portion is further compressed, cooled, and condensed, and used to provide refrigeration duty to a second precooling heat exchanger. Optionally additional precooling heat exchangers, and/or phase separators may be used.
    Type: Grant
    Filed: October 7, 2016
    Date of Patent: May 26, 2020
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Mark Julian Roberts
  • Patent number: 10544986
    Abstract: A system and method is provided for increasing the capacity and efficiency of natural gas liquefaction processes by debottlenecking the refrigerant compression system. A secondary compression circuit comprising at least one double flow compressor is provided in parallel fluid flow communication with at least a portion of a primary compression circuit.
    Type: Grant
    Filed: March 29, 2017
    Date of Patent: January 28, 2020
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Joseph Gerard Wehrman, Gowri Krishnamurthy, Mark Julian Roberts
  • Publication number: 20190331414
    Abstract: Described herein are methods and systems for the liquefaction of a natural gas feed stream using a refrigerant comprising methane. The methods and systems use a refrigeration circuit and cycle that employs two or more turbo-expanders to expand two or more streams of gaseous refrigerant down to different pressures to provide cold streams of at least predominantly gaseous refrigerant at different pressures that are used to provide refrigeration for precooling and liquefying the natural gas. The resulting liquefied natural gas stream is then flashed to produce an LNG product and a flash gas, the flash gas being recycled to the natural gas feed stream.
    Type: Application
    Filed: April 27, 2018
    Publication date: October 31, 2019
    Applicant: Air Products and Chemicals, Inc.
    Inventors: Gowri Krishnamurthy, Mark Julian Roberts