Patents by Inventor Harry S. Tang

Harry S. Tang 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).

  • Method of removing NH.sub.3 and HCN from and FCC regenerator off gas
    Patent number: 5240690
    Abstract: A method is disclosed for the addition of an oxygen-containing gas under certain defined process conditions, to an off-gas stream derived from an FCC regenerator which is operated in a partial mode of combustion. The off-gas from the regenerator contains 1-6% CO by volume and at least 300 ppm nitrogen compounds comprising NH.sub.3 and HCN. Without the addition of an oxygen-containing gas, roughly 25 percent of the NH.sub.3 and HCN are converted to NO.sub.x in downstream CO boilers. A preferable method of this invention comprises the addition of heated air (20% O.sub.2) into the regenerator off gas to produce an off gas stream having a temperature of 1260.degree. F. to 1500.degree. F.
    Type: Grant
    Filed: April 24, 1992
    Date of Patent: August 31, 1993
    Assignee: Shell Oil Company
    Inventors: Harry S. Tang, Gregory L. Johnson