| 摘要 |
<p>PURPOSE:To remove nitrogen and phosphorus in waster water efficiently by aerating waste water periodically in a periodic aeration chamber filled with a contractor bearing a biological film and activated sludge and separating the treated water into supernatant water and precipitating sludge after transferring the treated water to a precipitation chamber. CONSTITUTION:An organic nitrogen and ammonia-nitrogen in waste water are oxidized into nitrous acid or nitric acid by nitrification with nitrification bacterial when a periodic aeration chamber is in an aerobic condition at the time of aeration. After the aeration is stopped and the chamber becomes anaerobic condition, nitrous acid or nitric acid are reduced to nitrogen gas by denitrification bacteria and removed from the waste water. Phosphorus removing bacteria release phosphorus in the inside of themselves and makes precondition of taking in phosphorus at the time of anaerobic condition of the periodic aeration chamber and when the chamber is aerated and changes to aerobic condition, bacteria take phosphorus vigorously. The phosphorous removing bacteria which take phosphorus in the bacterial cells are precipitation-separated in a precipitation chamber while contained in precipitated sludge.</p> |
