Patents by Inventor Kyei-Sing Kwong

Kyei-Sing Kwong 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: 20180230390
    Abstract: Embodiments relate to methods, systems and an apparatus for determining an optimal temperature for gasification of a feedstock. The method includes predicting a chemistry of impurities in the feedstock that form a slag; predicting viscosity curves of the impurities in the feedstock that form the slag; predicting a need for one or more additives; and predicting an impact of chemistry changes of the slag based at least partly on temperature vs viscosity behavior during gasification. The method further includes controlling a gasification temperature to achieve a desired viscosity of the slag using at least one of the predicted chemistry changes and the additives.
    Type: Application
    Filed: February 12, 2018
    Publication date: August 16, 2018
    Inventors: Kyei-Sing Kwong, James Bennett
  • Patent number: 9598318
    Abstract: The disclosure provides a refractory brick system comprising a chromia refractory brick for operation in the slagging environment of an air-cooled gasifier. The chromia refractory brick comprises a ceramically-bonded porous chromia refractory having a porosity greater than 9% and having carbon deposits residing within the pores. The brick may be further comprised of Al2O3. The air-cooled gasifier generates a liquefied slag in contact with the refractory brick and generally operates at temperatures between 1250° C. and 1575° C. and pressures between 300 psi to 1000 psi, with oxygen partial pressures generally between 10?4 and 10?10 atm. The refractory brick performs without substantial chromium carbide or chromium metal formation in the low oxygen partial pressure environment. The inclusion of carbon without chromium carbide formation provides for significant mitigation of slag penetration and significantly reduced refractory wear.
    Type: Grant
    Filed: September 11, 2014
    Date of Patent: March 21, 2017
    Assignee: U.S. Department of Energy
    Inventors: James P. Bennett, Kyei-Sing Kwong
  • Patent number: 8703021
    Abstract: The disclosure provides methods of operating a slagging gasifier using a carbon feedstock having a relatively high V2O5 to SiO2 ratio, such as petcoke. The disclosure generates a combined chemical composition in the feed mixture having less than 25 wt. % SiO2, greater than 20 wt. % V2O5, and greater than 20 wt. % CaO. The method takes advantage of a novel recognition that increased levels of SiO2 tend to decrease dissolution of the V2O3 which forms under the reducing conditions of the gasifier, and utilizes the CaO additive to establish a chemical phase equilibria comprised of lower melting compounds. The method further provides for control based on the presence of Al2O3 and FeO, and provides for a total combined chemical composition of greater than about 5 wt. % MgO for use with refractory linings comprised of MgO based refractory brick.
    Type: Grant
    Filed: October 26, 2012
    Date of Patent: April 22, 2014
    Assignee: U.S. Department of Energy
    Inventors: Kyei-Sing Kwong, James P. Bennett, Jinichiro Nakano
  • Patent number: 6815386
    Abstract: A high-chromium refractory material that provides improved resistance to coal slag penetration is presented. The refractory mixture comprises a blend of chromium oxide, aluminum oxide and phosphates. The refractory mixture may be blended with an aggregate and cured. In addition a phosphorous oxide may be blended with chromium oxide and aluminum oxide and additionally an aggregate. The refractory mixture reduces the rate of coal slag penetration into the surface of the cured refractory.
    Type: Grant
    Filed: October 23, 2002
    Date of Patent: November 9, 2004
    Inventors: Kyei-Sing Kwong, Cynthia P. Dogan, James P. Bennett, Richard E. Chinn, Arthur V. Petty
  • Patent number: 5552353
    Abstract: A process for the synthesis of homogeneous advanced ceramics such as SiC+AlN, SiAlON, SiC+Al.sub.2 O.sub.3, and Si.sub.3 N.sub.4 +AlN from natural clays such as kaolin, halloysite and montmorillonite by an intercalation and heat treatment method. Included are the steps of refining clays, intercalating organic compounds into the layered structure of clays, drying the intercalated mixture, firing the treated atmospheres and grinding the loosely agglomerated structure. Advanced ceramics produced by this procedure have the advantages of homogeneity, cost effectiveness, simplicity of manufacture, ease of grind and a short process time. Advanced ceramics produced by this process can be used for refractory, wear part and structure ceramics.
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: September 3, 1996
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventor: Kyei-Sing Kwong