| 摘要 |
<p>A process for reducing the amount of excess sludge by aerobically treating an aqueous organic waste in an aeration tank in the presence of a biosludge containing aerobic microorganisms, subjecting the resulting mixed liquor to a solid/liquid separation, the so-separated liquid phase being discharged as treated liquor, and supplying at least a part of the separated biosludge, after having been treated with ozone, to the aeration tank, wherein the ozone treatment is realized by passing a mixed flow of a biosludge-containing liquor to be treated or a liquor containing the ozonized biosludge and of an ozone-containing gas through a flow-down pipe in a downward flow and introducing the flow into an ozone-treating vessel in a state in which the ozone-containing gas is dispersed as finely disintegrated bubbles, whereby clogging of gas diffuser due to adhesion of the biosludge is avoided and the ozone treatment is attained at a high ozone yield. <IMAGE></p> |
