Conversion of the Aeration System at the Stade Sewage Treatment Plant to Pressurised Aeration

Cause

Abwasserentsorgung Stade is converting the aeration system of aeration tanks 4 and 5 at the Stade sewage treatment plant to pressurised aeration. This measure involves replacing the old roller aerators with fine-bubble pressurised aerators with efficient compressed air units. The aim is to maximise energy savings with a corresponding significant reduction in CO2 emissions.

Process

The existing aeration tanks at the Stade sewage treatment plant can only be emptied with great operational effort. For this reason, the aerators were combined into several removable units. Plate aerators from RMU were used for this. To maximise the efficiency of the compressed air supply (5,000 m³/h), the new blower station consists of frequency-controlled turbo compressors, which are operated via an individually designed compressor control system in conjunction with air volume measurements and orifice regulating valves in the pressure lines.

The necessary mixing of the circulation tanks is ensured by the installation of new low-speed submersible mixers, which are also equipped with frequency converters for efficient speed control.