Patents by Inventor Yul Kwan

Yul Kwan 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: 9132385
    Abstract: The present invention is a combustion system employing a urea-to-ammonia vapor reactor system. The urea-to-ammonia reactor housing enclosed in a bypass flow duct that receives a secondary flue gas stream at a split point from a main flue gas stream containing nitrogen oxides (NOx) emanating from a boiler. The bypass flow duct allows the secondary flue gas stream to flow past the enclosed reactor housing where injected aqueous urea in atomized or non-atomized form, is gasified to ammonia vapor. The resulting gaseous mixtures of ammonia, its by-products and the secondary flue gas stream subsequently rejoin the main stream, before the main flue gases are treated through a Selective Catalytic Reduction (SCR) reactor apparatus. A residence time of the secondary stream within the bypass flow duct, which may be increased by a recirculation loop, enables effective conversion of urea to ammonia to be used in the SCR apparatus.
    Type: Grant
    Filed: November 5, 2010
    Date of Patent: September 15, 2015
    Assignee: Johnson Matthey Inc.
    Inventor: Yul Kwan
  • Publication number: 20140255289
    Abstract: The present invention is a combustion system employing a urea-to-ammonia vapor reactor system. The urea-to-ammonia reactor housing enclosed in a bypass flow duct that receives a secondary flue gas stream at a split point from a main flue gas stream containing nitrogen oxides (NOx) emanating from a boiler. The bypass flow duct allows the secondary flue gas stream to flow past the enclosed reactor housing where injected aqueous urea in atomized or non-atomized form, is gasified to ammonia vapor. The resulting gaseous mixtures of ammonia, its by-products and the secondary flue gas stream subsequently rejoin the main stream, before the main flue gases are treated through a Selective Catalytic Reduction (SCR) reactor apparatus. A residence time of the secondary stream within the bypass flow duct, which may be increased by a recirculation loop, enables effective conversion of urea to ammonia to be used in the SCR apparatus.
    Type: Application
    Filed: November 5, 2010
    Publication date: September 11, 2014
    Applicant: JOHNSON MATTHEY INC.
    Inventor: Yul Kwan
  • Publication number: 20120183447
    Abstract: The present invention is a method for selective reduction of nitrogen oxides in a gas stream with ammonia wherein the ammonia is vaporized prior to contacting it with the carrying fluid. The present invention also comprises a reducing agent dispersion system for use in substantially uniformly mixing a reducing agent with nitrogen oxides in a flue gas stream comprising a header and a plurality of lances. Further, the present invention comprises a novel reactor design for use in selective reduction of nitrogen oxides in a gas stream.
    Type: Application
    Filed: August 15, 2011
    Publication date: July 19, 2012
    Inventors: Yul Kwan, Rajashekharam V. Malyala, Robert Bono, Alec Miller, Stephen J. Golden
  • Patent number: 7998444
    Abstract: The present invention is a method for selective reduction of nitrogen oxides in a gas stream with ammonia wherein the ammonia is vaporized prior to contacting it with the carrying fluid. The present invention also comprises a reducing agent dispersion system for use in substantially uniformly mixing a reducing agent with nitrogen oxides in a flue gas stream comprising a header and a plurality of lances. Further, the present invention comprises a novel reactor design for use in selective reduction of nitrogen oxides in a gas stream.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: August 16, 2011
    Assignee: Johnson Matthey Inc.
    Inventor: Yul Kwan
  • Publication number: 20110133127
    Abstract: The present invention is a combustion system employing a urea-to-ammonia vapor reactor system. The urea-to-ammonia reactor housing enclosed in a bypass flow duct that receives a secondary flue gas stream at a split point from a main flue gas stream containing nitrogen oxides (NOx) emanating from a boiler. The bypass flow duct allows the secondary flue gas stream to flow past the enclosed reactor housing where injected aqueous urea in atomized or non-atomized form, is gasified to ammonia vapor. The resulting gaseous mixtures of ammonia, its by-products and the secondary flue gas stream subsequently rejoin the main stream, before the main flue gases are treated through a Selective Catalytic Reduction (SCR) reactor apparatus. A residence time of the secondary stream within the bypass flow duct, which may be increased by a recirculation loop, enables effective conversion of urea to ammonia to be used in the SCR apparatus.
    Type: Application
    Filed: November 5, 2010
    Publication date: June 9, 2011
    Applicant: JOHNSON MATTHEY INC.
    Inventor: Yul Kwan
  • Patent number: 7943097
    Abstract: A zeolite based SCR catalyst for NOx reduction using a reducing agent for treating exhaust streams from industrial and commercial boilers is provided. The reactor system has a zeolite based catalyst arranged in catalyst cassettes in a modular fashion where the reactor containing the zeolite based SCR catalyst cassettes is placed in a perpendicular direction to the exhaust exiting the industrial and/or commercial boiler. The catalyst selectively reduces nitrogen oxides to nitrogen with a reducing agent at low to medium temperatures. The reactor results in high NOx conversions and very low ammonia slip and is active for a wide range of boiler firing conditions. Boilers with low NOx and/or ultra low NOx burners can be replaced with a standard conventional burner for overall emissions reduction performance, efficiency improvements and energy savings. Boilers with low NOx and ultra low NOx burners can also be fitted with this zeolite based SCR catalyst reactor for additional NOx reductions and energy savings.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: May 17, 2011
    Assignee: Catalytic Solutions, Inc.
    Inventors: Stephen J. Golden, Svetlana Iretskaya, Rajashekharam V. Malyala, Guang Yuan, Rachelle Justice, Yul Kwan, Robert Bono, Ronald Roberts, Alec Miller
  • Publication number: 20090274601
    Abstract: The present invention is a method for selective reduction of nitrogen oxides in a gas stream with ammonia wherein the ammonia is vaporized prior to contacting it with the carrying fluid. The present invention also comprises a reducing agent dispersion system for use in substantially uniformly mixing a reducing agent with nitrogen oxides in a flue gas stream comprising a header and a plurality of lances. Further, the present invention comprises a novel reactor design for use in selective reduction of nitrogen oxides in a gas stream.
    Type: Application
    Filed: April 30, 2008
    Publication date: November 5, 2009
    Inventors: Yul Kwan, Rajashekharam V. Malyala, Robert Bono, Alec Miller, Stephen J. Golden
  • Publication number: 20080317652
    Abstract: This invention is an emission control system wherein the boiler hosts a reactor which contains one or more catalysts for the purpose of reducing NOx and/or CO in the emissions. The reactor containing the NOx/CO catalysts may be placed at a place where the temperature is in the range of 300-1000° F. The hot flue gas can be diverted using control dampers and blended with colder flue gas inside the boiler to achieve the desired flue gas temperature for the selected catalyst. NOx is removed by the SCR catalyst inside the boiler upon injecting a suitable reducing agent (e.g. ammonia, or hydrocarbons). The CO and NOx catalysts may be used in any order. The emission control system is an integral part of the boiler, and the existing capabilities of the boiler to recover the heat from flue gas, after the catalyst layers, is utilized such that the overall boiler efficiency remains high.
    Type: Application
    Filed: April 30, 2008
    Publication date: December 25, 2008
    Inventors: Robert Bono, Rajashekharam V. Malyala, Alec Miller, Yul Kwan, Stephen J. Golden
  • Publication number: 20080279741
    Abstract: A zeolite based SCR catalyst for NOx reduction using a reducing agent for treating exhaust streams from industrial and commercial boilers is provided. The reactor system has a zeolite based catalyst arranged in catalyst cassettes in a modular fashion where the reactor containing the zeolite based SCR catalyst cassettes is placed in a perpendicular direction to the exhaust exiting the industrial and/or commercial boiler. The catalyst selectively reduces nitrogen oxides to nitrogen with a reducing agent at low to medium temperatures. The reactor results in high NOx conversions and very low ammonia slip and is active for a wide range of boiler firing conditions. Boilers with low NOx and/or ultra low NOx burners can be replaced with a standard conventional burner for overall emissions reduction performance, efficiency improvements and energy savings. Boilers with low NOx and ultra low NOx burners can also be fitted with this zeolite based SCR catalyst reactor for additional NOx reductions and energy savings.
    Type: Application
    Filed: April 30, 2008
    Publication date: November 13, 2008
    Inventors: Stephen J. Golden, Svetlana Iretskaya, Rajashekharam V. Malyala, Guang Yuan, Rachelle Justice, Yul Kwan, Robert Bono, Ronald Roberts, Alec Miller