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:
Jun. 11, 2019
Filed:
Apr. 04, 2017
Hitachi, Ltd., Tokyo, JP;
Yuya Kimura, Tokyo, JP;
Shinichi Yoshikawa, Tokyo, JP;
Shoko Miyamae, Tokyo, JP;
Hajime Ikuta, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Provided is a method for treating ammoniacal nitrogen in wastewater performed via biologically oxidizing ammoniacal nitrogen, and producing nitrite nitrogen and nitrate nitrogen at a desired rate. In the method, ammoniacal nitrogen is oxidized by bacterial sludges to produce at least either of nitrite nitrogen and nitrate nitrogen. Specifically, the method includes an inactivating treatment step of treating the bacterial sludges with an inactivating operation via sterilizing bacteria or causing bacteriostasis, and a nitrifying treatment step of oxidizing the ammoniacal nitrogen by the bacterial sludges thus treated in the inactivating operation. Production amounts of the nitrite nitrogen and the nitrate nitrogen are controlled by adjusting biomass of the bacterial sludges to be treated in the inactivating operation, and/or a time interval between the inactivating operations each repeatedly performed in combination with the nitrifying treatment step.