Patents by Inventor by Elva R. O'Brien, executrix

by Elva R. O'Brien, executrix 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 for recycling paper mill waste water
    Patent number: 4115188
    Abstract: Disclosed is a method for coagulating the suspended solids in paper mill waste water so that the coagulated solids may be easily separated from the waste water and the clarified waste water reused in the paper making process. Coagulation is induced by first adding sulfuric acid to lower the pH to below 4, mixing thoroughly, and then adding calcium hydroxide to raise the pH to above 10. The coagulated solids separated from the waste water may be used as a landfill, used as a low grade pulp source, or dewatered and burned as a fuel.
    Type: Grant
    Filed: November 8, 1976
    Date of Patent: September 19, 1978
    Inventors: Richard C. O'Brien, deceased, by Elva R. O'Brien, executrix