Patents by Inventor Nitin Ramesh Keskar

Nitin Ramesh Keskar 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: 6537514
    Abstract: In a method for the production of carbon dioxide, an oxygen-containing first process gas is flowed along a cathode side of a first oxygen selective ion transport membrane. The membrane is at operating conditions effective to transport a first permeate oxygen portion from the cathode side to an opposite anode side. A carbon-containing second process gas is flowed along the anode side at a flow rate effective to provide a stoichiometric surplus of oxygen on combination with the first permeate oxygen portion. A first mixture of a second process gas and the first permeate oxygen portion is combusted such that substantially all of the second process gas is converted into a second mixture of water and carbon dioxide. The carbon dioxide is separated from such second mixture.
    Type: Grant
    Filed: October 26, 1999
    Date of Patent: March 25, 2003
    Assignee: Praxair Technology, Inc.
    Inventors: Ravi Prasad, Christian Friedrich Gottzmann, Nitin Ramesh Keskar, Joseph Michael Schwartz
  • Publication number: 20030039601
    Abstract: A reaction vessel for the production of synthesis gas that contains four subassemblies: (1) a first heat exchanger that transfers heat between two low pressure streams (an oxygen containing stream and an oxygen depleted stream); (2) a second heat exchanger that transfers heat between two high pressure fluid streams (a hydrocarbon-containing reactant stream and a synthesis gas product stream); (3) mixed conductor ceramic membranes; and (4) a catalyst bed. Each of these subassemblies are configured so that they freely expand or contract independently from each other, and to thus avoid inducing high mechanical loads and damaging material stresses.
    Type: Application
    Filed: August 10, 2001
    Publication date: February 27, 2003
    Inventors: Thomas Gilbert Halvorson, Victor Emmanuel Bergsten, Prasad S. Apte, Nitin Ramesh Keskar, Christo Steyn, Richard Andrew Vanslooten
  • Patent number: 6375913
    Abstract: An integrated system for producing high purity silicon dioxide comprising: a) a source of an oxygen-containing feed gas containing at least one impurity, b) an oxygen transport membrane cell containing an oxygen-selective transport membrane that has a cathode side and an opposing anode side, the membrane being at an elevated temperature effective for separation of oxygen in the feed gas from the impurity by transporting oxygen ions from the oxygen-containing feed gas through the membrane to the anode to form a purified oxygen permeate on the anodeside, while retaining an essentially oxygen-depleted, impurity-containing retentate on the cathode side, c) a passageway from the source (a) to the cathode side of the membrane cell, d) a silicon source, and e) a silicon oxidation furnace, in communication with the anode side of the membrane cell, for reaction of the purified oxygen permeate with silicon from the silicon source, at an elevated reaction temperature effective for the reaction, in order to produce the h
    Type: Grant
    Filed: April 10, 2000
    Date of Patent: April 23, 2002
    Assignee: Pranair Technology
    Inventors: Kevin Bruce Albaugh, Nitin Ramesh Keskar
  • Patent number: 6139604
    Abstract: A low energy cost process for the co-production of oxygen and nitrogen employing a fuel tube extending into the first oxygen selective ion transport membrane whereby fuel is introduced adjacent to the closed end and flows cocurrently with oxygen containing gas in the annulus and an oxygen selective ion transport membrane having a separator section and a reactor section. An oxygen-containing feedstock, typically air, is compressed and then contacts the cathode side of the separator section where a portion of the oxygen contained within the feedstock is transported to the anode side of the separator section and recovered as an oxygen product gas. Substantially the remainder of the oxygen contained within the feedstock is transported from the cathode side of the reactor section to the anode side and exothermically reacted with a fuel. Following the exothermic reaction, hot nitrogen rich product gas is expanded in a turbine to generate the power necessary to compress the feedstock.
    Type: Grant
    Filed: November 4, 1998
    Date of Patent: October 31, 2000
    Assignee: Praxair Technology, Inc.
    Inventors: Christian Friedrich Gottzmann, Ravi Prasad, Nitin Ramesh Keskar, James Bragdon Wulf
  • Patent number: 6106591
    Abstract: A process for inhibiting the formation of carbon and/or coke from a carbon-containing reactive gas stream on the permeate side of an oxygen ion transport membrane, or for increasing the oxygen partial pressure thereon, by separating a feed gas stream to form an oxygen-depleted gas stream on the retentate side and a gas stream containing oxygen reaction products on the permeate side. The permeate side is purged with the carbon-containing reactive gas stream, and at least a portion of the exhaust gas stream formed from the reaction of the reactive gas stream with the separated oxygen is recirculated to purge the permeate side.
    Type: Grant
    Filed: November 5, 1998
    Date of Patent: August 22, 2000
    Assignee: Praxair Technology, Inc.
    Inventors: Nitin Ramesh Keskar, Ravi Prasad, Christian Friedrich Gottzmann
  • Patent number: 6066307
    Abstract: A process for producing synthesis gas and hydrogen by passing a compressed and heated oxygen-containing gas mixture into a reactor having at least one solid electrolyte oxygen ion transport membrane to separate transported oxygen Organic fuel reacts with the oxygen to form synthesis gas. The resulting synthesis gas is separated into hydrogen gas through at least one solid electrolyte hydrogen transport membrane to separate the transported hydrogen in the same or different separator.
    Type: Grant
    Filed: September 15, 1999
    Date of Patent: May 23, 2000
    Inventors: Nitin Ramesh Keskar, Ravi Prasad, Christian Friedrich Gottzmann
  • Patent number: 6017646
    Abstract: An integrated system utilizing a solid oxide fuel cell and at least one ion transport reactor to generate electric power and a product gas by delivering an oxygen-containing gas, typically air, to a first cathode side of the solid oxide fuel cell and delivering a gaseous fuel to a first anode side. Oxygen ions are transported through a membrane in the fuel cell to the first anode side and exothermally react with the gaseous fuel to generate electric power and heat. The heat and oxygen transport produces a higher-temperature, reduced-oxygen-content gaseous retentate stream exiting the cathode side of the solid oxide fuel cell which is delivered to a first ion transport reactor where a substantial portion of the residual oxygen is transported through an oxygen selective ion transport membrane. A product gas stream is then recovered.
    Type: Grant
    Filed: June 3, 1998
    Date of Patent: January 25, 2000
    Assignee: Praxair Technology, Inc.
    Inventors: Ravi Prasad, Christian Friedrich Gottzmann, Nitin Ramesh Keskar
  • Patent number: 6010614
    Abstract: A method for maintaining the temperature of an oxygen-selective ion transport membrane within a desired temperature range includes providing an ion transport reactor with the oxygen-selective ion transport membrane. An oxygen-donating feed gas is delivered to a cathode side at a first temperature, at a first rate, and at a first oxygen partial pressure and a reactant gas is supplied to an anode side at a second temperature and a second rate. A physical condition is then established within the ion transport reactor that favors the transport of elemental oxygen through the oxygen selective ion transport membrane as oxygen ions. One or more process variables are then regulated to maintain the temperature of the oxygen selective ion transport membrane within the desired range.
    Type: Grant
    Filed: June 3, 1998
    Date of Patent: January 4, 2000
    Assignee: Praxair Technology, Inc.
    Inventors: Nitin Ramesh Keskar, Ravi Prasad, Christian Friedrich Gottzmann
  • Patent number: 5964922
    Abstract: A process for producing a gas stream containing oxygen and steam to feed a coal gasifier or other downstream process by compressing and heating a feed gas stream, and separating the heated feed gas stream into an oxygen-depleted gas stream on a retentate side of an ion transport membrane and an oxygen-containing gas stream on a permeate side. The permeate side is purged with a purge gas stream containing steam to produce a gas stream containing oxygen and steam, and at least a portion of the gas stream containing oxygen and steam is fed to the coal gasifier after blending with a pure oxygen stream recovered from the remaining portion of the purge stream or by a parallel nonpurged ion transport separator in the system to achieve the appropriate steam-to-oxygen ratio for the downstream process.
    Type: Grant
    Filed: November 18, 1997
    Date of Patent: October 12, 1999
    Assignee: Praxair Technology, Inc.
    Inventors: Nitin Ramesh Keskar, Ravi Prasad, Christian Friedrich Gottzmann
  • Patent number: 5954859
    Abstract: A process for producing an oxygen-depleted gas stream and a high-pressure gas stream containing oxygen and steam by compressing a feed gas stream containing elemental oxygen, heating the feed gas stream, and separating the heated feed gas stream using one or more ion transport modules into the oxygen-depleted gas stream on a retentate side and an oxygen gas stream on a permeate side of an ion transport membrane. The permeate side is purged using a high-pressure purge gas stream containing steam to produce the high-pressure gas stream containing oxygen and steam, which is directed to a turbine to recover power and produce an expanded, lower-pressure gas stream containing oxygen and steam.
    Type: Grant
    Filed: November 18, 1997
    Date of Patent: September 21, 1999
    Assignee: Praxair Technology, Inc.
    Inventors: Nitin Ramesh Keskar, Ravi Prasad, Christian Friedrich Gottzmann
  • Patent number: 5888272
    Abstract: A process for separating a feed gas stream into an oxygen-enriched gas stream which is used in a combustor and an oxygen-depleted gas stream. The feed gas stream is compressed, and oxygen is separated from the compressed feed gas stream using an ion transport module including an ion transport membrane having a retentate side and a permeate side. The permeate side of the ion transport membrane is purged with at least a portion of a combustion product gas stream obtained from the combustion in the combustor of the gas stream exiting the permeate side of the ion transport module.
    Type: Grant
    Filed: June 5, 1997
    Date of Patent: March 30, 1999
    Assignee: Praxair Technology, Inc.
    Inventors: Ravi Prasad, Christian Friedrich Gottzmann, Raymond Francis Drnevich, Nitin Ramesh Keskar, Hisashi Kobayashi
  • Patent number: 5837034
    Abstract: A process for inhibiting the formation of carbon and/or coke from a carbon-containing reactive gas stream on the permeate side of an oxygen ion transport membrane, or for increasing the oxygen partial pressure thereon, by separating a feed gas stream to form an oxygen-depleted gas stream on the retentate side and a gas stream containing oxygen reaction products on the permeate side. The permeate side is purged with the carbon-containing reactive gas stream, and at least a portion of the exhaust gas stream formed from the reaction of the reactive gas stream with the separated oxygen is recirculated to purge the permeate side.
    Type: Grant
    Filed: June 23, 1997
    Date of Patent: November 17, 1998
    Assignee: Praxair Technology, Inc.
    Inventors: Nitin Ramesh Keskar, Ravi Prasad
  • Patent number: 5837125
    Abstract: A system and process for producing a high-purity product from a feed stream containing elemental oxygen by applying the feed stream to at least one separator including a feed zone and a permeate zone separated by a solid electrolyte membrane, and driving a portion of oxygen contained in the feed stream from the feed zone to the permeate zone via the membrane by applying to the permeate zone a reactive purge stream containing a reactive gas which combines with oxygen to establish a lower partial pressure of oxygen in that zone. Oxygen-depleted retentate is withdrawn as a high-purity product stream.
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: November 17, 1998
    Assignee: Praxair Technology, Inc.
    Inventors: Ravi Prasad, Christian Friedrich Gottzmann, Nitin Ramesh Keskar
  • Patent number: 5820655
    Abstract: An ion transport reactor and process for using same having at least one ion transport membrane with a retentate side and a permeate side, for extracting oxygen from a feed gas stream as it flows along the retentate side. A reactant gas stream is flowed along the permeate side of the ion transport tubes to react with the oxygen transported therethrough. Heat is transferred to a fluid stream flowing through the ion transport reactor while the temperature of the membrane is maintained within its operating range.
    Type: Grant
    Filed: April 29, 1997
    Date of Patent: October 13, 1998
    Assignee: Praxair Technology, Inc.
    Inventors: Christian Friedrich Gottzmann, Ravi Prasad, Victor Emmanuel Bergsten, Nitin Ramesh Keskar, Bart Antonie van Hassel