摘要 |
<p>A process for purifying waste water by means of activated sludge in which the waste water to be purified is taken into an aeratable sludge basin (1) followed by a sedimentation basin (5) in which the sludge and clear water are separated, whereafter sludge is taken back to the sludge basin (1) and clear water is drawn off; an operating cycle takes place in the sedimentation basin (5) several times a day in which the sludge is again mixed with the water (agitation phase R) and the withdrawal phase (A) of the operating cycle is separated from the agitation phase (R) by an interval (presedimentation phase V).</p> |