METHOD FOR TREATING DRAINAGE CONTAINING AMMONIA

摘要

PROBLEM TO BE SOLVED: To separate/decompose ammonia in drainage containing ammonia by a method in which the drainage is stripped by spraying into a spray tank at a specified pressure to be separated into ammonia gas and water, and the separated ammonia gas is decomposed catalytically to obtain nitrogen and water. SOLUTION: In the treatment of drainage containing ammonia, the drainage in a raw water tank 1 is passed through a reverse osmosis membrane separator 2, the filtrate is supplied to a treated water tank 3, while the concentrated water is circulated to the raw water tank 1 in order to increase the ammonia concentration of the drainage. The drainage with an increased ammonia concentration is pressurized by a high pressure pump 4 and sprayed at 100 kg/cm<2> or above into a spray tank 5 to be separated into ammonia gas and treated water. The treated water after the separation of ammonia is drawn out from the bottom part of the spray tank 1 and returned the raw water tank 1, and the circulation is performed until the ammonia concentration of the treated water reaches a prescribed concentration.