ENREM Enhanced Nutrients Removal in Biomembrane Reactor

Demonstration project on application of membrane bioreactor technology for advanced treatment of wastewater in sensitive and remote areas

Project partners KWB, BWB, Veolia, sub-contractors
Project volume 3.400.000 €
Project start01.01.2004
Duration36 months

The project is being co-financed in the framework of the LIFE Programme of the European Commission (Reference No. LIFE04 ENV/D/058) with a contribution of 562.463 €.





Position of the demonstration site of Margaretenhöhe (Source BWB).
Position of the demonstration site of Margaretenhöhe (Source BWB).
Concept of containerised MBR-plant (courtesy of A3 GmbH).
Concept of containerised MBR-plant (courtesy of A3 GmbH).
Example of a 300 p.e. MBR plant in South Wraxall, UK (Source Aquator internet site).
Example of a 300 p.e. MBR plant in South Wraxall, UK (Source Aquator internet site).
MBR pilot plant to validate design and operation criteria (Source TUB).
MBR pilot plant to validate design and operation criteria (Source TUB).

Context

Still today in Berlin, some remote small catchments are not connected to the central sewer system. The technology of membrane activated sludge, or membrane bioreactor (MBR), could well provide a technical and economical solution for semi-central wastewater treatment plants in environmentally sensitive areas. Such a process could indeed achieve complete disinfection and advanced biological phosphorus removal down to 0.1mgP/L or lower, with no or very limited addition of metal salts for phosphorus precipitation. This treatment enables to comply with the European guidelines on bathing water and to reduce eutrophication of surface water bodies. The implementation of MBR technologies on small or medium-size catchments could be achieved in containerised turn-key units in order to reduce construction costs, and should not entail the usual inconveniences of wastewater treatment plants to the local neighbourhood, namely odour and noise emissions, and increased truck traffic.

In order to validate the technical and economical feasibility of this concept, Berliner Wasserbetriebe and Veolia Water have undertaken and completed the 3-year “IMF project”, from 2001 to 2003 in the frame of the Berlin Centre of Competence for Water. During this R&D project, an innovative membrane process was optimised at pilot plant scale for advanced treatment of municipal wastewater. This patented process developed with the MBR technology, combines enhanced biological phosphorus and nitrogen removal in a post-denitrification step, and provides an effluent quality surpassing any conventional technologies utilised to date for decentralised treatment. In addition to complete disinfection through the microfiltration membrane, improved removal of nutrients and pollutants were achieved with elimination rates of 99% for phosphorus (<50µgP/L) and 95% for nitrogen (<5mgN/L). This outstanding treatment performance was achieved over a broad range of operation conditions, confirming the flexibility and robustness of the process configuration, and without resorting to any chemical additive such as metal salts (for phosphorus precipitation) or carbon source (for improved denitrification). Moreover, cost estimations underlined the economical benefits of this solution, for the water utility as well as for the concerned households, to equip remote and unsewered areas when compared with conventional treatment processes achieving a similar effluent quality.
Here Diagram Capex MBR / Other processes (directly in text, no hyperlink)
Legend. Comparison of capital costs between membrane bioreactor and conventional technologies.

 

Comparison of capital costs between membrane bioreactor and conventional technologies.
Comparison of capital costs between membrane bioreactor and conventional technologies.

Objectives

The ENREM demonstration project aims at undertaking the first full-scale assessment of this innovative process. A treatment plant will be built in Berlin to serve a community of about 200 inhabitants. The effluent will be characteristic of a decentralised area, i.e. it will contain neither industrial wastewater nor storm water.
After commissioning and start-up, this plant will be operated continuously treating the collected sewage to a quality beyond the EU criteria for sensitive area and bathing water. The operation of the system will be assessed and optimized over more than 1.5 year in order to identify the best operation conditions to achieve the required discharge criteria at least operation cost, and any issue related to full-scale implementation.
The ENREM demonstration plant will be the first full-scale MBR plant designed and operated with biological phosphorus removal in Europe. Furthermore, at the time of its commissioning, it will be the MBR plant achieving worldwide the greatest rate of phosphorus and nitrogen elimination. A successful completion of the project would open the implementation of this process to other applications in Germany, Europe or worldwide.

The ENREM process flowsheet, with anaerobic zone and post-denitrification for advanced biological nutrients removal.
The ENREM process flowsheet, with anaerobic zone and post-denitrification for advanced biological nutrients removal.

Implementation

 Criteria 

 Goal (grab sample) 

 Disinfection 

 EU-guidelines for bathing water 

 Phosphorus 

 < 0.1 mgP/L (99% removal)

 Nitrogen

 < 10 mgN/L (90% removal) 

title
Contact

Boris Lesjean, KompetenzZentrum Wasser Berlin gGmbH
Boris.Lesjean(at)kompetenz-wasser.de
Regina Gnirss, Berliner Wasserbetriebe
Regina.Gnirss(at)bwb.de