METHOD OF TREATMENT OF SEWAGE WATERS OF UREA PRODUCTION PROCESS Russian patent published in 2000 - IPC

FIELD: treatment of sewage waters containing ammonia and urea. SUBSTANCE: method consists in that sewage waters after hydrolysis and desorption are subjected to treatment with active chlorine with air supply at pH 6.5-8 in amount of 5-7 weight parts per weight part of ammonium nitrogen with subsequent anionation. Treatment with active chlorine may be accomplished with gaseous chloride or with calcium or sodium hypochlorite. EFFECT: higher efficiency of purification of sewage waters and attaining quality of purified sewage meeting the requirements for chemically treated water, for instance, for supply of medium pressure boilers with P=4 MPa (kgf/sq.cm), or possible use in systems of circulating water supply. 4 cl, 3 ex