| 摘要 |
<p>PURPOSE:To selectively suppress the development of filiform bacteria in activated sludge, by charging the amount of chlorine corresponding to 5-60ppm of the amount of inflow filthy water at an arbitrary position of the aeration tank of a microbic oxidizing apparatus having said aeration tank. CONSTITUTION:By the apparatus comprising a tank 16 for sodium hypochlorite, a tank 17 for hydrochloric acid and a measuring tank 18 for supplying the fixed amount of each of them, a mixed liquid (a 12% sodium hypochlorite solution and an 18% hydrochloric acid solution are usually used) is charged through a passageway 19 in the vicinity 5 of the filthy water inflow part of an aeration tank 4. After solid matter is removed in a primary precipitation pool 2, inflow filthy water is charged by fixed quantities in the aeration tank 4. The aeration tank 4 is filled with MLSS in the concentration of 1,000-10,000ppm. Treated water is separated from sludge in a precipitation pool 8. The former is drained outside the apparatus, while the latter is partially returned as returned sludge through a passageway 12 to the aeration tank 4.</p> |
