The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 29, 1980
Filed:
Oct. 25, 1978
Gilbert V Levin, Chevy Chase, MD (US);
Biospherics Incorporated, Rockville, MD (US);
Abstract
There is disclosed an activated sludge sewage treatment process which comprises mixing influent sewage material with activated sludge and bio-surface particulates to provide a mixed liquor. The mixed liquor is passed to an aeration zone wherein it is contacted with an oxygen-containing gas to reduce the BOD content thereof. The mixed liquor is then passed to a settling zone in which it is settled to separate bio-surface particulates having sludge particles adherent thereto and a clarified supernatant. The clarified supernatant is removed from the settling zone and is discharged as effluent or routed for further treatment. At least a portion of the bio-surface particulates having sludge adherent thereto is subjected to a treatment to separate at least a portion of the adherent sludge particles. The thus treated portion of the bio-surface particulates, which may still have some sludge particles adherent thereto, and separated sludge particles is then passed to a bio-surface particulate sludge separator. In this separator, the sludge present in the mixture which is not adherent to the bio-surface particulates separates from the bio-surface particulates and at least a portion of the sludge is passed out of the system as waste sludge which is essentially free of the biosurface particulates. The bio-surface particulates and remaining sludge are then recycled for mixing with said influent sewage material.