The RBC method utilises immobilized biomass growing on a partially submerged, rotating polypropelene disc. The biomass settles on the disc and is repeatedly dipped into the wastewater to provide nutrients, and then lifted into the air to allow aerobic metabolism. Since it is not necessary to move the entire volume of water, the RBC method has always been one of the most energy-efficient aeration methods. In addition, oxygen in the ambient air is not a limiting factor - even at high temperatures or high altitude.

Compared to the classic activated sludge method, the disc provides up to 100 times more fixed biomass. Therefore, the RBC method is not only suitable for sewage plants with variable loads, but also generates significantly less excess sludge due to the high mean cell residence time. The resulting sedimentary sludge settles easily and has a very high degree of mineralization, making it highly compact.

Even in thin mountain air, oxygen is not a limiting factor. At high temperatures (e.g. desert climate), the evaporative cooling effect on the discs regluates the temperature within the system to facilitate the purification process.

Due to the compact design, the biodiscs must be provided with sufficient acid capacity and enough time for the metabolic process to take place. Particular attention should be paid to the issue of solids and contaminants.

With System S&P's sewage treatment plants, our customers are well prepared for the future.