Aeration panels replaced: Repair work on the sewage treatment plant completed

An aeration tank at the Bocholt sewage treatment plant has been extensively renovated in recent weeks. Defective aeration plates had to be replaced in order to restore the oxygen supply for the microorganisms that purify the wastewater. The plant is now fully operational again.

The team at Entsorgungs- und Servicebetrieb Bocholt (ESB) has replaced around 100 aeration plates in the so-called aeration tank 2. These plates are located at the bottom of the tank and release fine bubbles of air into the wastewater. The rising air bubbles supply the microorganisms with oxygen, which break down organic substances in the water. In recent years, the performance of the aeration system had increasingly deteriorated - some of the plates were damaged and now had to be replaced.

"The aeration plates ensure that our microorganisms in the aeration tank are supplied with sufficient oxygen", explains wastewater treatment plant manager Christian Schaffeldt. This is the only way the organisms can break down the harmful substances in the water, explains Schaffeldt. To replace the plates, the basin was temporarily taken out of operation, completely emptied and cleaned.

The removed plates are refurbished in the factory of a specialised company and can then be reused in other plants. Refurbished aeration panels have now been installed in Bocholt.

The work took around three weeks. During this time, the operation of the sewage treatment plant was ensured by the two other aeration tanks. "Such repairs are always a challenge because the processes in the sewage treatment plant are precisely synchronised", says Schaffeldt. "Thanks to the good preparation and teamwork, however, we were able to put the tank back into operation quickly."

Once assembly was complete and the test runs had been successfully completed, the tank was refilled and connected to the overall system. The Bocholt wastewater treatment plant treats up to 25,000 cubic metres of wastewater every day - in rainy weather, this volume can increase to up to 100,000 cubic metres.