Patent ID: 7297276
Filing Date: 2007-11-20
Classification: C02F

Abstract:
1. A method for treating water containing ammonium-nitrogen in which raw water containing ammonium-nitrogen is introduced into a nitrification tank, a part of the aminonium-nitrogen in the raw water is oxidized into nitrite-nitrogen by the action of ammonium oxidizing bacteria, and nitrification of the nitrite-nitrogen by nitrite oxidizing bacteria is inhibited, thereby conducting nitrification of nitrous acid, wherein inorganic carbon concentration in the nitrification tank is maintained at 35 mg-C/L or more, nitrified liquid from the nitrification tank is introduced into a denitrification tank and denitrification reaction is conducted by action of denitrifying bacteria with remaining ammonium-nitrogen acting as an electron donor and the nitrite-nitrogen acting as an electron acceptor, and the denitrifying bacteria is anaerobic ammonium oxidation bacteria.