Patent EP-2289855-A1 (EP)
Inventor: HARTWIG PETER
IPC: C02F3/30
Filed: 2009-08-31
Abstract: The wastewater purification system comprises an inflow mixing tank (3), a combined reaction- and sedimentation tank (1, 2) having first and second tank sections. A first connection point (11) is disposed between the inflow mixing tank and the first tank section in a lower tank area of the first tank section. A first conveying device is arranged at the first connection point and is operatable for conveying a return activated sludge from the first tank section into the inflow mixing tank. A first clear water discharge point (13) is disposed in an upper tank area of the first tank section. The wastewater purification system comprises an inflow mixing tank (3), a combined reaction- and sedimentation tank (1, 2) having first and second tank sections. A first connection point (11) is disposed between the inflow mixing tank and the first tank section in a lower tank area of the first tank section. A first conveying device is arranged at the first connection point and is operatable for conveying a return activated sludge from the first tank section into the inflow mixing tank. A first clear water discharge point (13) is disposed in an upper tank area of the first tank section. A second connection point (21) is disposed between the inflow mixing tank and the second tank section in the lower tank area of the second tank section. A second conveying device is arranged at the second connection point and is operatable for conveying the return activated sludge from the second tank section into the inflow mixing tank. A second clear water discharge point is disposed in the upper tank area of the second tank section. A first feeding point is disposed between the inflow mixing tank and the first tank section in the lower tank area of the first tank section for supplying the wastewater to be purified from the inflow mixing tank into the combined reaction- and sedimentation tank. A second feeding point is disposed between the inflow mixing tank and the second tank section in the lower tank area of the second tank section for supplying the wastewater to be purified from the inflow mixing tank into the combined reaction- and sedimentation tank. The first connection point is equal to the first feeding point and/or the second connection point is equal to the second feeding point. A control device is provided for controlling the operation of the first and second conveying devices and is arranged to operate the first conveying device or the second conveying device or temporally overlapping both conveying devices for conveying the return activated sludge from the reaction- and sedimentation tank into the inflow mixing tank for a short time period in comparison to the duration of the sedimentation phase. The reaction- and sedimentation tank has a reaction section for reaction treatment of the tank content and a sedimentation section for temporal simultaneous sedimentation of the tank content. In a first operating phase of the wastewater purification system, the first tank section is the reaction section and the second tank section is the sedimentation section. In a second operating phase of the wastewater purification system, the first tank section is the sedimentation section and the second tank section is the reaction section. The reaction- and sedimentation tank is connected with a sludge post-treatment tank over a further connection point. The wastewater purification system includes aerobic, anoxic or anaerobic operated sludge post-treatment tank with biological activity, a sludge guiding point disposed in the lower tank area of the sludge post-treatment tank, and a sludge water outlet point or a sludge water overflow disposed in an above situated tank area of the sludge post-treatment tank. The sludge water outlet point is connected with the reaction- and sedimentation tank and/or the inflow mixing tank, and is disposed at the side of the sludge post-treatment tank opposite to the sludge guiding point. An independent claim is included for a method for operating a wastewater purification system.