Fulfilling treatment requirements to a high level of protection
Tummelsta is a community situated outside Eskilstuna by the Borsten lake. It is a popular area for summer residences, with 78 cottages. In the fall of 2013, the decision was made to build a water-treatment plant for 45 households. After a further 2½ years, the plant would be expanded to serve an additional 15 households, in order to cope with the increased flow of wastewater. The biggest challenge was to meet the requirement for a 90% reduction of phosphorus in the wastewater with a solution that would also be environmentally friendly.
Filter beds with phosphorus filters
The solution was to expand the treatment plant with more septic tanks, sand bed sections and filter wells to ensure that the plant would be able to cope with more households in the future. The treatment plant was dimensioned for 150 p.e. but has a capacity of up to 200 p.e., thanks to the expansion. Together with the Tummelsta residents, Ecofiltration developed a solution for the removal of phosphorus that diverts the wastewater from the pump house to a septic tank, where the sludge is separated from the water. The water then continues through a sand bed and, in the final stage, is filtered through a container that contains Polonite in bulk.
Outperforms the requirements for phosphorous reduction
This solution has proved to have an extremely positive effect, and the removal of phosphorus exceeded requirements tenfold, <0.05 mg/l Tot-P. The Swedish Environmental Services Department has confirmed that this treatment plant achieves a reduction in phosphorus of at least 90% – and even up to 99% – which also meets the area’s requirements for a high level of protection. The solution installed by Ecofiltration, with an expansion of the treatment plant and phosphorus treatment with Polonite, prevents both any further emission of phosphorus and eutrophication. Furthermore, Tummelsta is able to reuse the saturated filter material as fertilizer for the local area.
- Tummelsta, Eskilstuna, Sweden
- Community with private sewers and a wastewater treatment plant for 150-200 p.e.
- Challenge: To deliver a 90% reduction in phosphorus using an environmentally-friendly solution
- Solution: Filter beds with Polonite in bulk
- Easy to install, easy to maintain, exceeds the requirements for phosphorus treatment
- Contractor: Ericsson & Söner Åkeri AB