The objective with the facility was from the beginning to provide a basis for building a full-scale plant for Hammarby Sjöstad. Later the Sjöstadsverket also started to focus on providing a basis for improvements in existing WWTPs in Stockholm. Funds came from different sources e.g. a project about pharmaceuticals. A significant part of the performed research at the facility has been reported by some 30 Master-theses from various colleges and universities.
Results from experiments with the various process lines may thus provide both the knowledge of various components, processes and system performance. Some of the results of earlier experiments are as follows:
- The process line that simulates the operation of Henriksdal proved to give representative results. BioP worked, but required an extra carbon source. It was possible to precipitate the phosphorus from the digester reject as a crystalline product.
- A drumfilter is a clear alternative to sedimentation. Aerobic MBR worked technically very stable with sludge concentrations between 12 and 20 g/L. Outgoing water is particle free, and it is therefore easy to separate the nutrients with reverse osmosis, RO. The water from the MBR has a great potential for reuse when it does not contain parasites or pathogenic bacteria.
- It was shown that it is possible to produce biogas with direct anaerobic treatment of municipal wastewater without heating, even in winter time.
- Biologically treated water could be separated by RO to over 98% of very pure water and less than 2% concentrate with almost all nutrients.
- Separate management of toilet wastewater in an anaerobic MBR and RO can produce so much biogas and nutrients that it is at least from an energy viewpoint equivalent to traditional systems.