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:
Jan. 30, 1979
Filed:
Dec. 22, 1976
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C02B / ; C02C / ;
U.S. Cl.
CPC ...
210 16 ; 71 10 ; 71 12 ; 210 18 ; 210 28 ; 210 48 ; 210 53 ; 210D / ; 210D / ;
Abstract
A process for the tertiary treatment of biochemical waste waters comprising the following 4 main steps; (1) adding milk of lime to waste water from the anaerobic digestion treatment process to render the waste water alkaline and recovering NH.sub.3 by reduced pressure distillation, (2) contacting recovered NH.sub.3 with a weakly acidic ion exchange resin to make NH.sub.3 adsorbed in the ion exchanger resin, (3) adding acid to the adsorbed ammonia to form an ammonia salt, and (4) blowing CO.sub.2 into the treated water from which NH.sub.3 has been removed, to thereby recover P, and subjecting the treated water from which N and P have been removed to the activated sludge treatment to remove BOD.