| 摘要 |
<p>PURPOSE:To efficiently denitrify intrified water contg. activated sludge at an increased denitrification rate by denitrifying the water while agitating with gas of high CO2 concn. to control shift of the water to the alkali side. CONSTITUTION:N-contg. water to be treated is fed 3 to divided vessel 1a of catalytic nitrification vessel 1 and aerated by supplying 5a O2-contg. gas. The aerated water is sent to divided vessel 1b to nitrify the dissolved N with intrate-forming bacteria, etc. in activated sludge under aerobic conditions. The nitrified water is fed to denitrification vessel 8 together with the sludge and agitated by blowing 12 gas T of high CO2 concn. through aerator 11. At this time, an org. C source such as methanol necessary to facultative anaerobic denitrification bacteria is supplied into vessel 8 beforehand. The nitrified water is biochemically reduced in vessel 8 to gasification-remove the N contained. The CO2 blown maintains the pH of the water optimum and facilitates activation of the denitrification bacteria.</p> |
