Containerised membrane bioreactors are gaining popularity not only for the use in mobile applications. In the past they were only used for temporary operation (in military champs for example), now they are increasingly used also for other applications in municipal and industrial wastewater treatment because they can quickly be implemented virtually without any construction work.

The pilot version of the first containerised solution of a complete plant with membrane technology was assembled in our factory in spring 2011 and installed and put into operation on WWTP Mühlhausen near Berching in June 2011. It is planned to use this containerised plant as a basis module to optimize process variants, such as SMBR with different configurations. Furthermore, different additional modules are planned to be coupled with it to obtain a complete system: mechanical pre-treatment system, phosphate precipitation and sludge treatment plant. We are also thinking about to extend the degree of plant automation and control via several sensors. The later standard version of the prototype is planned to be used not only in temporary applications such as labour camps but especially also in new markets, such as Green Building or other municipal and industrial applications. Other potential applications are for example remote or small villages that do not have much space for a big sewage treatment plant or for which the connection to an existing sewage treatment plant would be uneconomical.

The SMBR process is a modification of the SBR process (Sequencing Batch Reactor) which uses a membrane filtration unit instead of a final sedimentation and settling phase. The great advantage of this system is its small space requirements compared to conventional MBR plants. The different biological processes do not take place in different places but are separated in time, with the result of a reduced permeate discharge time. This seeming disadvantage is compensated by partly significantly increased permeate volume flows.

For the test operation on WWTP Mühlhausen the raw wastewater to be treated is taken from the grit trap on the WWTP and intermediately stored in a tank from where the membrane plant is fed. The two HUBER BioMem® filtration units with 75 m² membrane surface each are at the core of the containerised plant. The system is a redundant two-line design. The permeate is discharged via a pump. The scouring air for each filtration unit is supplied by a scouring blower. But these scouring blowers supply not only the scouring air for the filtration modules (type HUBER BioMem®), they also ensure oxygen supply to the biological system. In addition, the plant is equipped with a surplus sludge pump, oxygen and solids sensors and on-site control system.

The test program has been composed to answer questions related to the optimal timing of SMBR processes with nitrification or denitrification, the scouring air and oxygen demand of the biological system, optimal DS content, maximum flux, or backwash pressures and times. Furthermore, the pilot tests will be used to optimize chemical purification and document system performance by means of lab samples. In addition, staff of subsidiaries and customers will be invited to receive training on site with a plant that is in operation.