Biological treatment of waste water containing nitrogen compound and dithionic acid

Abstract

Abstract PURPOSE:To treat efficiently waste water contg. hardly decomposable COD and nitrogen compds. by adding org. substance to the waste water contg. nitrogen compds. and dithionic acid, removing hydrogen sulfide to treat anaerobically, and subjecting to a biological nitrification and denitrification treatment by introducing the aforesaid hydrogen sulfide to the treated liquid. CONSTITUTION:Waste water 1 contg. NH3 and dithionic acid is charged into an anaerobically decomposition tank 2, and after adding a proper amount of methanol or the like, gas is introduced to stirr. The dithionic acid is changed to hydrogen sulfide and the hydrogen sulfide is adsorbed to an absorbent in an absorber 5. The decomposed liquid 7 is introduced into the first anaerobical denitrification tank 10 with a returned sludge 8 and circulated nitrification liquid 9, reduced, and decomposed to N2 gas by denitfification bacteria using the hydrogen sulfide absorbent 11 from the absorber 5 as a reductant. The decomposed liquid is further oxidized to NOX in a nitrification tank 13, reduced, and decomposed to N2 gas using hydrogen sulfide absorbed in the hydrogen sulfide absorbent 11 in the second denitrification tank 14 as the reductant. The treated liquid is aerated in a reaeration tank 15, and separated to treated water 16' and surplus sludge 12 in a settling tank 16.

Inventors

• 👤 Takayuki Suzuki
• 👤 隆幸 鈴木
• 👤 Kaneaki Endo
• 👤 銀朗 遠藤
• 👤 Yoshitaka Matsuo
• 👤 松尾　吉高

Bibliographic Details