Patents by Inventor Leon Yuan

Leon Yuan 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: 20080159930
    Abstract: In one exemplary embodiment, a process for regenerating a hydrocarbon conversion catalyst for a hydrocarbon conversion zone can generally include passing the hydrocarbon conversion catalyst through, sequentially, a catalyst-disengaging zone having a first atmosphere, an adsorption zone having a second atmosphere, and a regeneration zone including a combustion zone; introducing an inert gas between the first atmosphere and the second atmosphere; and passing a flue gas from the combustion zone to the adsorption zone.
    Type: Application
    Filed: April 6, 2007
    Publication date: July 3, 2008
    Inventors: David J. Fecteau, Leon Yuan
  • Publication number: 20080156699
    Abstract: One exemplary embodiment is a refinery or a petrochemical production facility. The refinery or petrochemical production facility can include: a) a catalyst regeneration zone; b) a halogen removal zone; and c) an elimination zone for at least one of a dioxin and a furan compound, wherein at least a portion of an effluent from the halogen removal zone is combined with a stream comprising oxygen from the catalyst regeneration zone or halogen removal zone.
    Type: Application
    Filed: April 5, 2007
    Publication date: July 3, 2008
    Inventors: Leon Yuan, Steven M. Poklop, William D. Schlueter
  • Publication number: 20080156695
    Abstract: A process for reforming a hydrocarbon stream in a reforming unit can include passing a gas including a halogen-containing material from a product separation zone through an adsorption zone to remove at least some of the halogen-containing material before the gas enters a first reforming stage having at least one fixed bed reaction zone.
    Type: Application
    Filed: September 7, 2007
    Publication date: July 3, 2008
    Inventors: Gary A. Dziabis, Leon Yuan, David J. Fecteau
  • Publication number: 20080110801
    Abstract: An exemplary process can include passing a hydrocarbon stream through a reforming unit. The reforming unit may include a heater, which in turn generally includes a convection section and a radiant section, and a plurality of reforming reaction zones. Generally, the hydrocarbon stream is heated in the convection section for reacting in one of the reforming reaction zones to which the hydrocarbon stream is sent and the hydrocarbon stream is heated in the radiant section of the heater for reacting in the other reforming reaction zone to which the hydrocarbon stream is sent.
    Type: Application
    Filed: November 9, 2006
    Publication date: May 15, 2008
    Inventors: Leon Yuan, David J. Fecteau, William M. Hartman, William D. Schlueter
  • Patent number: 7312173
    Abstract: This invention relates to regeneration of coked catalyst by combustion so that the catalyst can be reused in a hydrocarbon conversion reaction. The completion of coke burn is generally measured with a combination of temperature or change in oxygen concentration. Dropping outlet temperatures require time to wait for increases in inlet temperature to correspondingly move down the regenerator. Faster response times might be expected from increasing oxygen concentration, but a small increase in concentration can lead to a significant increase in peak burn temperature which negatively impacts catalyst life. Controlled peak burning is difficult over the entire bed by merely controlling inlet and outlet oxygen concentrations. The invention accordingly combines a measured lag time for temperature travel with an inlet temperature ramping step to ensure complete coke combustion with high oxygen efficiency, thus providing a rapid regeneration that permits more time for operation at desired reaction conditions.
    Type: Grant
    Filed: December 31, 2003
    Date of Patent: December 25, 2007
    Assignee: UOP LLC
    Inventors: Leon Yuan, James L. Bixby, Kyle P. Austin, Brian D. Nabozny
  • Publication number: 20070217961
    Abstract: This invention relates to regeneration of coked catalyst by combustion so that the catalyst can be reused in a hydrocarbon conversion reaction. The completion of coke burn is generally measured with a combination of temperature or change in oxygen concentration. Dropping outlet temperatures require time to wait for increases in inlet temperature to correspondingly move down the regenerator. Faster response times might be expected from increasing oxygen concentration, but a small increase in concentration can lead to a significant increase in peak burn temperature which negatively impacts catalyst life. Controlled peak burning is difficult over the entire bed by merely controlling inlet and outlet oxygen concentrations. The invention accordingly combines a measured lag time for temperature travel with an inlet temperature ramping step to ensure complete coke combustion with high oxygen efficiency, thus providing a rapid regeneration that permits more time for operation at desired reaction conditions.
    Type: Application
    Filed: May 31, 2007
    Publication date: September 20, 2007
    Inventors: Leon Yuan, James Bixby, Kyle Austin, Brian Nabozny
  • Patent number: 7098300
    Abstract: Disclosed is a multistage fluidized SSP reactor that tightens the distribution of residence time and the resulting average intrinsic viscosity of the polymer product. Less residence time is needed to achieve a desired average intrinsic viscosity. As the polymer beads continuously flow through sequential stages, poly-condensation reactions continue to develop almost under plug-flow conditions. Five fluidized stages or more provide advantageous performance.
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: August 29, 2006
    Assignee: UOP LLC
    Inventors: Chi-Chin Chen, Leon Yuan