Patent ID: 6033569
Filing Date: 2000-03-07
Classification: C02F,Y02W,Y10S

Abstract:
A nitrifying method, wherein liquid containing ammonia is brought into contact with nitrifying bacteria in the aerobic condition to thereby nitrify ammonium nitrogen in the liquid containing ammonia,wherein:in the nitrifying process, the liquid containing ammonia having an ammonium nitrogen concentration of 400 mg/l or more in the liquid is brought into contact with fixed media of floating type, in which AH bacteria as being the nitrifying bacteria grow preferentially; andthe load of the ammonium nitrogen per fixed medium of floating type is 500 mg-N/h.multidot.l-medium or more so as to perform the nitrifying reaction of nitrous acid, in which a generation rate of the nitrous acid is 80% or more in all nitrogen oxide which is generated by nitrifying the ammonium nitrogen in the liquid containing ammonia.