Case Study Activated Sludge Plant

Replacement of low-speed surface aerators

The biological stage of a sewage treatment plant in Germany consists of a rectangular activated sludge basin and a final clarifier. Two pole-changing surface aerators are installed at bridges. Due to their age the aerators are worn. They can only be used at the lower speed. As oxygen transfer was no longer sufficient, the plant was retrofitted with two FUCHS OXYSTAR Aerators.


Type of wastewater: municipal
Design capacity:
approx. 10,500 p.e.
Activated sludge basin
  • volume:
  • water depth:
1,300 m³
3.5 m
Equipment:2 x FUCHS OXYSTAR Aerator 
(nominal power: 15.0 kW each)





  • The FUCHS OXYSTAR Aerators are fixed at the walls of the basin with a mounting bracket. Additional supports or the installation of new bridges were not necessary.
  • During installation the operation of the treatment plant was not interrupted and the basin did not have to be emptied.    
  • The aerators are switched on and off depending on the actual oxygen demand.


Efficient and economical wastewater treatment


Activated Sludge Plants
Oxygen for clear water with FUCHS Aerators