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:
Mar. 30, 2004
Filed:
Dec. 30, 2002
Hiren K. Trivedi, Cedar Park, TX (US);
Enviroquip, Inc., Austin, TX (US);
Abstract
In the liquid side of sewage treatment process, a combination aerobic/anoxic stage is closely monitored such that phosphorus can be removed as well as nitrogen. As in a known process, the aerobic/anoxic stage is monitored as to a coenzyme of the active bacteria. When the bacteria of flocs within this stage show a switch to anaerobic condition via such coenzyme, the low dissolved oxygen level in the stage is maintained for a preselected period of time or to a preselected extent of the anaerobic condition, before oxygen is added. This somewhat brief anaerobic condition within the flocs is sufficient to release significant amounts of phosphorus into the liquid. When aeration then is increased, enhanced biological phosphorus uptake is effected. A small aerobic stage is included after the aerobic/anoxic stage to ensure maximum phosphorus uptake, and in one embodiment this stage includes a membrane separator, allowing downstream secondary clarification to be eliminated.