| 摘要 |
PURPOSE:To effectively utilize ozone in purification of night soil without necessity of active carbon, by mixing exhaust gas from an ozone-decolorization step in a night soil-purifying plant with aerating air for an active sludge process, and blowing the gaseous mixture into an aeration vessel. CONSTITUTION:Exhaust gas discharged from an ozone-decoloring column 12 is treated in a defoaming column 18 to separate bubbles from it, and inhaled and mixed in aerating air through an ejector 20 located in an aerating air conduit from a blower 16 to an aerating vessel 7. The gaseous mixture is blown into the aerating vessel 7 through a sparger 17. If water, to be purified, in the aerating vessel 7 contains very high concentration of organic substances, the water is anaerobically digested, mixed with diluting water 5 at a rate of 19pts.vol. by 1pt.vol. of digested effluent, and then aerated. The resultant BOD is at 25,000mg/ l or so. When ozone is injected into such water containing BOD at high concentration, ozone is absorbed in the water to be purified, and unreacted ozone is not discharged from the aerating vessel. |
