| 摘要 |
<p>PURPOSE:To perform nitration, denitrification and the lowering of the quantity of oxygen bilogically demanded simultaneously and excellently under a mixing condition by a method wherein digestion tanks are connected to an excrements storage tank and a mixing decomposing tank is connected to the digestion tanks. CONSTITUTION:The excrements in the storage tank 2 is introduced into the first and second digestion tanks 3a, 3b, gas containing oxygen is supplied and the excrements is oxidized. A mixing tank 9 is put between the second digestion tank 3b and a mixing separation tank 4, the excrements from the storage tank 2 is fed to dilute a liquid in the tank 9 while activated sludge recovered from a sedimentation tank 5 and a coagulating and settling tank 6 at succeeding stages is supplied, and the whole is uniformly mixed. The mixture is forwarded to a mixing decomposing tank 4, air, etc. are fed from an air dispersing pipe 13, water to be disposed is oxidized, and nitration, the lowering of the quantity of oxygen biologically demanded and nitriding disposal are simultaneously performed. Sludge is separated at the sedimentiation tank 5, a coagulant is added at a mixer 14, and flocks are formed, and supplied to the coagulating and settling 6.</p> |
