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:
Feb. 16, 1982
Filed:
Oct. 10, 1978
David C Climenhage, Kingston, CA;
Du Pont Canada Inc., Mississauga, CA;
Abstract
An improved process is disclosed for the treatment of aqueous waste streams containing nitrogenous matter (nitrate or nitrite ions or matter capable of forming nitrate and nitrite ions) in the presence of sufficient carbonaceous matter to permit substantially complete denitrification of the aqueous effluent. The process comprises introducing an aqueous waste stream having a pH less than 6 into an anaerobic treatment zone containing anaerobic activated sludge at a rate such that the concentrations of nitrate and nitrite ions in the anaerobic treatment zone are maintained at a level less than 3 milligrams/liter. In embodiments, the effluent from the anaerobic treatment zone is passed to an aerobic treatment zone effluent from which is recycled at a rate at least equal to that at which untreated waste is fed to the anaerobic treatment zone. The waste stream feed may contain phenol.