Patents by Inventor Lars-Erik Hagerstedt

Lars-Erik Hagerstedt 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 of sewage treatment
    Patent number: 5114587
    Abstract: The present invention refers to a process for wastewater treatment, wherein the amount of soluble organic matter is reduced by means of addition of nitrate. A relief of the wastewater treatment plants is obtained by the fact that the agent is added as early as possible in the pipe line net. The addition of nitrate may be controlled by measurement of the redox potential.
    Type: Grant
    Filed: January 4, 1991
    Date of Patent: May 19, 1992
    Assignee: Hydro Supra AB
    Inventor: Lars-Erik Hagerstedt