摘要 |
The invention relates to a method for carrying out biological purification of wastewater with the aid of activated sludge, in which the wastewater is introduced into an activated sludge tank (B tank) and then, in alternation, into one of a number of sedimentation and recirculation tanks (SU tanks) continuously connected hydraulically to the B tank and in which a number of operating cycles are carried out, including a sludge return phase, a mixing phase, a sedimentation phase and a draw-off phase (S phase, U phase, V phase, and A phase respectively), wherein the method further includes elimination of phosphor by using a tank for biological phosphor elimination (P tank), wherein the P tank is hydraulically connected with the B tank via one or more openings, wherein the wastewater is first introduced into the P tank and then subsequently transferred into the B tank, wherein in the S phase at least part of the thickened activated sludge is introduced from the SU tank into the P tank, and, wherein the volume of the P tank is mixed permanently or intermittently. |