Patents by Inventor Robert M. Vallowe

Robert M. Vallowe 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).

  • Crystal modification in wet process phosphoric acid production
    Patent number: 5009873
    Abstract: A wet process production of phosphoric acid in which phosphate rock is digested, whereby phosphoric acid is released and calcium sulfate crystals are formed, employs a polymeric crystal modifier in the digestion stage of the process to improve the separation of the raw phosphoric acid product from the calcium sulfate crystals and to increase the concentration of phosphoric acid in the raw phosphoric acid product.
    Type: Grant
    Filed: January 29, 1990
    Date of Patent: April 23, 1991
    Assignee: Nalco Chemical Company
    Inventors: E. Michael Kerr, Lawrence J. Connelly, William J. Roe, Robert M. Vallowe