During static thickening of treated sludge sludge water will occur, which will have to be transported to the intake of the sewage treatment plant. A special sucking device will do this job. In this construction a submersible sewage pump is installed in the basin upside down by means of a lowering device in such a way that the sludge water can be sucked off during operation. As the water in the basin surrounds the motor of the pump it is always properly cooled.
The position of the pump is adapted to the water level in the basin by means of the lowering device. An alternative to the installation with lowering device is to fix the pump with a pontoon on the water surface. This means that the pump automatically adapts to changing water levels and is always ready for operation.
This system is also used in SBR-installations for removing clear water. After the sedimen-tation phase the clear water can be pumped off by using the system with pontoon.
The removal of floating sludge on final clarification basins is a task that constantly occurs. By installing the lowering device at the scraper bridge the floating sludge can be sucked off and transported to the sludge treatment.