Abstract: The present invention generally relates to vacuum pressure swing adsorption (VPSA) processes and apparatus to recover carbon dioxide having a purity of approximately ?90 mole % from streams containing at least carbon dioxide and hydrogen (e.g., syngas). The feed to the CO2 VPSA unit can be at super ambient pressure. The CO2 VPSA unit produces three streams, a H2-enriched stream, a H2-depleted stream and a CO2 product stream. When the CO2 VPSA unit is installed between an SMR/shift reactor and a H2 PSA unit, hydrogen recovery is expected to be increased by extracting CO2, thereby increasing hydrogen partial pressure in the H2 PSA feed. The stream from the CO2 VPSA unit, normally used as fuel, is recycled as feed to increase CO2 recovery. The recovered CO2 can be further upgraded, sequestered or used in applications such as enhanced oil recovery (EOR).
Abstract: A gas mixture preheated to high temperatures using an oxy-fuel, an oxygen-enriched air-fuel or an air-fuel burner is used to devolatilize and partially oxidize carbonaceous feedstock, thereby producing an active residual char that can be used in applications utilizing activated carbon. Use of hot gas and ground carbonaceous feedstock allows the equipment to be minimized, thereby allowing the activated carbon to be produced at or near points of use, for example the production of activated char at or near utility boilers for use in the reduction of mercury emissions from flue gas streams.
Type:
Grant
Filed:
September 12, 2005
Date of Patent:
April 27, 2010
Assignee:
Praxair Technology, Inc.
Inventors:
Lawrence E. Bool, III, Chien-Chung Chao, Mark K. Weise, Jurron L. D. Bradley
Abstract: The carbon monoxide and hydrocarbon content of flue gas in a cement clinker production apparatus is lowered by feeding a high velocity stream of hot oxygen into the flue gas. Methods and apparatus for producing the hot oxygen stream are disclosed.
Type:
Grant
Filed:
September 25, 2008
Date of Patent:
March 23, 2010
Assignee:
Praxair Technology, Inc.
Inventors:
Stefan Ernst Friedrich Laux, Lee Jonathan Rosen
Abstract: Heating provided by a burner that combusts hydrocarbon fuel can be provided at a sequence of different heat transfer rates by adjusting the total oxygen concentration of oxidant streams fed to the burner. A burner with which the method can be practiced is also disclosed.
Type:
Grant
Filed:
November 27, 2007
Date of Patent:
June 23, 2009
Assignee:
Praxair Technology, Inc.
Inventors:
William Thoru Kobayashi, Abilio Tasca, Francisco Dominques Alves De Sousa
Abstract: Emissions of NOx and CO are reduced from combustion devices such as coal-fired furnaces by increasing the stoichiometric ratio of burner(s) having a lower average temperature and increasing the stoichiometric ratio of burner(s) having a higher average temperature.
Type:
Grant
Filed:
December 8, 2005
Date of Patent:
March 3, 2009
Assignee:
Praxair Technology, Inc.
Inventors:
Edward Kaczenski, Lawrence E. Bool, III, Hisashi Kobayashi
Abstract: Combustion of hydrocarbon fuel is achieved with less formation of NOx by feeding the fuel into a slightly oxygen-enriched atmosphere, and separating air into oxygen-rich and nitrogen-rich streams which are fed separately into the combustion device.
Type:
Grant
Filed:
September 16, 2003
Date of Patent:
February 3, 2009
Assignee:
Praxair Technology, Inc.
Inventors:
Hisashi Kobayashi, Lawrence E. Bool, William J. Snyder
Abstract: A method for producing liquefied natural gas wherein high pressure liquid natural gas is subcooled and then flashed to form flash vapor and liquefied natural gas product, and the flash vapor is employed in a refrigeration cycle to generate refrigeration for subcooling the liquid natural gas.
Abstract: A hot oxygen stream is fed into a catalyst regenerator flue gas stream that contains carbon monoxide to remove carbon monoxide. NOx precursors such as NH3 and HCN are converted into N2 and if NOx is present in the flue gas stream the addition of the hot oxygen stream lowers the amount of NOx present.
Type:
Grant
Filed:
December 21, 2005
Date of Patent:
December 30, 2008
Assignee:
Praxair Technology, Inc.
Inventors:
Lee Rosen, Kuang Tsai Wu, Mushtaq M. Ahmed
Abstract: Byproduct solids produced in the processing of carbohydrate material to produce ethanol are dried in a recirculating stream of gaseous carbon dioxide into which carbon dioxide produced in that processing is fed. Organic contaminants and water vapor report to the recirculating carbon dioxide stream and are removed therefrom.
Abstract: In a kiln whose interior is heated by combustion with oxidant having a higher oxygen content than air, streams of staging oxidant are fed into the space between the combustion zone and the inner surface of the kiln, and the stoichiometric ratios and amounts of oxygen in the combustion zone and in the overall operation of the kiln are adjusted to provide control or reduction of NOx formation while maintaining or increasing productivity of the kiln.
Abstract: Bubbles of uniform diameter of 0.5 to 4 cm of gas such as helium are formed and pass into liquid such as molten glass by accumulating a sufficient volume of gas through a flow restriction into a space upstream of the point of injection at a controlled flow rate.
Type:
Grant
Filed:
May 25, 2005
Date of Patent:
November 18, 2008
Assignee:
Praxair Technology, Inc.
Inventors:
Nancy Newlin, legal representative, John F. Pelton
Abstract: Combustion of hydrocarbon liquids and solids is achieved with less formation of NOx by feeding a small amount of oxygen into the fuel stream.
Type:
Grant
Filed:
May 11, 2007
Date of Patent:
October 21, 2008
Assignee:
Praxair Technology, Inc.
Inventors:
Hisashi Kobayashi, Lawrence E. Bool, III
Abstract: A method for producing liquefied natural gas employing two separate adsorption steps for removing water and carbon dioxide from natural gas and employing a subambient expansion to produce regeneration gas for the regeneration of the dehydration adsorption step in addition to supplying refrigeration for the cooling or liquefaction of clean natural gas.
Type:
Grant
Filed:
October 13, 2004
Date of Patent:
June 19, 2007
Assignee:
Praxair Technology, Inc.
Inventors:
Henry Edward Howard, Minish Mahendra Shah
Abstract: A method for producing liquefied natural gas wherein high pressure liquid natural gas is subcooled and then flashed to form flash vapor and liquefied natural gas product, and the flash vapor is employed in a refrigeration cycle to generate refrigeration for subcooling the liquid natural gas.
Abstract: Combustion of hydrocarbon liquids and solids is achieved with less formation of NOx by feeding a small amount of oxygen into the fuel stream.
Type:
Grant
Filed:
May 13, 2003
Date of Patent:
June 5, 2007
Assignee:
Praxair Technology, Inc.
Inventors:
Hisashi Kobayashi, Lawrence E. Bool, III
Abstract: A method for generating refrigeration for cooling a product gas wherein a first or working gas undergoes a staged expansion to a first temperature and a subsequent turboexpansion to a second higher temperature and both the expanded gas and the turboexpanded gas provide cooling to the product gas.
Abstract: Liquid such as water is deaerated by dissolving stripping gas such as carbon dioxide into the water while maintaining pressure, reducing the pressure, and then feeding the liquid into a vessel wherein a gas space is maintained over said water, wherein the pressure of said gas space is less than the pressure upstream, and separately withdrawing degassed liquid and evolved gas from said vessel at rates which maintain the pressure of said gas space below the pressure upstream of said means.
Type:
Grant
Filed:
July 18, 2003
Date of Patent:
January 3, 2006
Assignee:
Praxair Technology, Inc.
Inventors:
William Robert Williams, Marcilio Paiva Prado, Luis Claudio Dias Nogueira
Abstract: Fuel such as coal is combusted by feeding fuel and gaseous oxidant containing more than 21 vol. % oxygen, and preferably 21.8 to 29 vol. % oxygen, to a combustion stage at a stoichiometric ratio below that at which, if the stage were operated with air as the only oxidant, the same amount of NOx would be produced, and combusting the fuel and oxidant in said stage to produce combustion products and unburned fuel.
Type:
Grant
Filed:
December 19, 2002
Date of Patent:
October 25, 2005
Assignee:
Praxair Technology, Inc.
Inventors:
Hisashi Kobayashi, Lawrence E. Bool, III