Patents by Inventor Douglas S. Hubbell

Douglas S. Hubbell 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: 20240026231
    Abstract: A method for enhancing the recovery of styrene includes feeding a hot liquid residue stream to a stripping vessel from a styrene monomer purification finishing system. The hot liquid residue stream includes styrene and compounds less volatile than styrene. The method includes introducing a gas to the stripping vessel to strip a portion of the styrene as vapor, generating a vaporized styrene portion, returning the vaporized styrene portion and the gas to the styrene monomer purification finishing system, recovering at least a portion of the vaporized styrene portion into a styrene monomer product, and producing a final liquid residue stream from a bottom of the stripping vessel with a lower concentration of styrene than the hot liquid residue stream feeding the stripping vessel.
    Type: Application
    Filed: July 22, 2022
    Publication date: January 25, 2024
    Inventors: Douglas S. Hubbell, Slawomir A. Oleksy
  • Patent number: 7402290
    Abstract: Methods and apparatus are disclosed for mixing fluid streams of different compositions to minimize fluid condensation inside a mixing vessel where the objective is to produce an all-vapor mixture product.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: July 22, 2008
    Assignee: Stone & Webster Process Technology Inc.
    Inventors: Douglas S. Hubbell, Dino Pizzelli, Edward P. Hunt, Glenn D. Nasman
  • Patent number: 6376736
    Abstract: A continuous process for integrated processing of a C8+ aromatic hydrocarbon stream is disclosed for recovery of a high purity meta-xylene product in conjunction with efficient separation and recovery of purified para-xylene and, optionally, purified ortho-xylene products.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: April 23, 2002
    Assignee: Washington Group International, Inc.
    Inventors: Philippe W. M. Rutten, James S. Law, Douglas S. Hubbell
  • Patent number: 5811629
    Abstract: Improved process and apparatus for purifying paraxylene from mixed C8-aromatic feedstocks are disclosed in which the use of at least two crystallization stages operated at different temperatures in combination with a final product separator improves purity and recovery while reducing capital and energy costs.
    Type: Grant
    Filed: September 20, 1996
    Date of Patent: September 22, 1998
    Assignee: Raytheon Engineers & Constructors, Inc.
    Inventors: Douglas S. Hubbell, Philippe W. M. Rutten