Patents by Inventor Nguyen L. Kim

Nguyen L. Kim 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).

  • Process for waste water treatment by removal of sodium sulfate
    Patent number: 5346620
    Abstract: The present invention is a process for treatment of waste water streams having a sodium sulfate content of above 20 percent. The process is useful for treating waste water generated in the production of polyethyleneimine and cyclohexanone. The process includes the steps of removing sodium sulfate from waste water by the addition of organic solvent. The waste water having reduced sodium sulfate content is then subjected to biological treatment with activated sludge. First the waste water is subjected to pre-treatment. Pre-treated waste water is combined other waste water and treated by denitrification and nitrification.
    Type: Grant
    Filed: August 31, 1993
    Date of Patent: September 13, 1994
    Assignee: BASF Corporation
    Inventors: David C. Hendrix, Andrew J. McNabb, Nguyen L. Kim, Michael Loden, Jaime R. Morales