METHOD OF PURIFYING AMMONIA-CONTAINING WASTE WATER BY REGULATING pH Russian patent published in 2011 - IPC C02F3/30 C02F3/12 C02F3/02 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of purifying ammonia-containing waste water in an SBR-reactor in a system with activated sludge in which during a first reaction, ammonia is converted to a nitrite, and in a simultaneously flowing second reaction, ammonia and nitrite are converted to molecular nitrogen, where concentration of oxygen in the reactor is kept at a low level. In order to implement the disclosed method, pH value of the system is kept at the desired level which, depending on oxygen transfer efficiency (OTE), lies in a range defined by the formula pHs = 7.55 - 3*OTE/100 ± 0.05, and by regulating periodic aeration. The range of deviation of pH from the given value is at most 0.05, preferably 0.02, and concentration of oxygen is kept between 0.2 mg/l and 0.4 mg/l, preferably between 0.25 mg/l and 0.35 mg/l.

EFFECT: accurate regulation of a narrow range of pH values of the treatment system by regulating periodic aeration ensures a stable process.

5 cl, 4 dwg