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. 24, 1990
Filed:
Feb. 06, 1989
William M Copa, Wausau, WI (US);
Thomas J Vollstedt, Schofield, WI (US);
Zimpro/Passavant Inc., Rothschild, WI (US);
Abstract
A two-stage process for purifying wastewater includes the steps of biophysical anaerobic treatment to remove the majority of the COD, followed by biophysical aerobic treatment to further purify the wastewater. A powdered adsorbent, preferably powdered activated carbon, is used with biological solids in each treatment step. Excess biophysical solids from the aerobic step are transferred to the anaerobic step for digestion. Fresh powdered adsorbent is added to the aerobic treatment step to compensate for that transferred to the anaerobic treatment step. Solids concentration in the anaerobic step is controlled by wasting solids to disposal.