| 摘要 |
<p>PURPOSE:To prevent the generation of smell and improve the quality of treating water by limiting the amount of sludge returned to a preaerating tank, feeding an oxygen enriching gas and feeding the waste gas thereof into an aerating tank in subjecting org. waste liquid to aerobic treatment. CONSTITUTION:Org. waste liquid 1 is successively passed through a preaerating part 3, a dilution control part 5 which dilutes the waste liquid by means of diluting water 4, an aerating part 6, and a settling part 7. The activated sludge settled and separated in the part 7 is returned via a return line 10 into the part 3 and the part 6, respectively, by using pumps 9. At this time, the amount of the sludge to be returned into the part 3 is kept at >=10% of the supplied org. waste liquid 1. An oxygen enriching gas as an oxygen source necessary for aerobic oxidation is fed into the hermetic type preaerating part 3 through a supply pipe 2 so that the org. waste liquid and the return sludge are mixed and aerated. The waste gas of the part 3 is fed as an oxygen source for the hermetic type aerating part 6 through a communicating pipe 11, and the dilution-controlled preaerating part treating liquid is further mixed and aerated. The waste gas is released from a pipe 12.</p> |
