Patents Assigned to Dravco Corporation
  • Patent number: 4332092
    Abstract: There is a disclosed a process and apparatus wherein a solvent-enriched material is introduced into a desolventizer-toaster tower to form a desolventized material which is introduced into a dryer and heated in the absence of air to form a dried material and a vapor steam including solvent which is compressed and passed to the desolventizer-toaster tower to provide all or a portion of the sparger steam requirements therefor.
    Type: Grant
    Filed: September 24, 1980
    Date of Patent: June 1, 1982
    Assignee: Dravco Corporation
    Inventor: Roger J. Hansotte
  • Patent number: 4159945
    Abstract: A method for denitrification of aqueous nitrate-containing solutions is disclosed. Specifically the invention provides for denitrification of the effluent from an activated sludge sewage treatment process. Effluent from the settling zone of an activated sludge sewage treatment process containing nitrogen compounds such as nitrates and nitrites, is passed through a deep bed filter, the filter media of which has been innoculated with bacteria that converts the nitrogen compounds to nitrogen gas. The filter, in addition to removing the nitrogen compounds, also removes suspended solids from the settling zone effluent, so that the final effluent from the filter is concurrently clarified and denitrified. By controlling the backwash of the filter, bacteria is retained thereon so as to enable continuous use of the filter for denitrification.
    Type: Grant
    Filed: January 31, 1974
    Date of Patent: July 3, 1979
    Assignee: Dravco Corporation
    Inventor: Elton S. Savage