Patents by Inventor Derrick A. Hill

Derrick A. Hill 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).

  • Removal of AOX FRM bleach plant mill effluents by pH shift using the alkalinity/acidity sources available at the mill
    Patent number: 5120448
    Abstract: A process for removal of adsorbable organic chlorine (AOX) in which the acid-soluble AOX present in kraft chlorination (C.sub.D) effluents are destablized and converted to inorganic chloride by pH shift using the alkalinity and acidity sources available at the mill; C.sub.D effluent, typically having a pH of 1-2 and E.sub.1 effluent, typically having a pH of 9-12 can be mixed in various proportions to achieve a pH between 6.5-9.0 or the C.sub.D effluent is adjusted in pH to 6-11 with an alkaline composition so taht alkaline hydrolysis as well as precipitation of organic material occurs and the treated effluent contains less AOX than present in the original untreated effluents; the AOX removal is enhanced substantially by (i) the presence of a sulphide or (ii) by carrying out the alkaline treatment at elevated temperature and pressure.
    Type: Grant
    Filed: September 19, 1990
    Date of Patent: June 9, 1992
    Inventors: Josesph G. Dorica, Joseph Sullivan, Maurice Douek, Derrick A. Hill, George M. Milosevich, John P. Morgan