Sequencing Batch Reactor

The sequencing batch reactor method (abbreviated SBR ) method is a variant of the conventional activated sludge process. SBR is comprised of a reaction chamber, the first performs the function of a biological reactor, and then that of a sedimentation basin. In contrast to continuously flowed through the SBR reactors is intermittently filled and emptied. The conventional physical separation of the biological processes and sedimentation is replaced by a time. The time interval from the beginning of the filling process to the end of the clear water drawing-off and a possible rest is referred to as a cycle. The SBR process can only be performed by at least 2 pools. These are always running from one cycle, this is different from treatment plant to treatment plant. A simple cycle is filling - mixing -fill- aeration - sedimentation - decantation. In sedimentation, the sludge settles down and in the Dean -tion drives a telescopic slide down subtracts the clear water layer. This method is often used in industrial wastewater treatment plants.

The SBR cycle is characterized by a successive temporal process phase sequence. The hydraulic isolation of the SBR process make it possible to make the duration, frequency and placement of the phases of the cycle is variable. The cycle starts with the filling phase, the starting processes, the first degradation already under anaerobic or anoxic conditions. In the actual degradation or reaction period, the reactor is vented. Depending on the cleaning target and non-aerated phases can be introduced. It follows the sedimentation phase, in which the activated sludge settles and forms a clear water layer. In the decant phase, the supernatant clear water is drawn off. Subsequently, an operational or rest phase following the cycle begins again. A separate secondary clarification is not necessary in the SBR process.

An example of an SBR plant in Sollenau, District Wr. Neustadt in Lower Austria:

• Design capacity: 60,000 pe
• Max inlet: 12,000 m³ / day
• Efficiency of COD (2005): 94.5 %
• Efficiency of BOD (2005): 97.9 %
• 4 pools each with 7988 m³
• Sludge production t ~ 3000 and ~ 23% TS content

Even small sewage treatment plants to be built in SBR technology since 2000. Since then, this technique has become the best-selling small sewage treatment system. The effluent quality today reached the same level as municipal wastewater treatment plants.