In Sweden more than 400 000 private households have not yet sufficient wastewater purification. These effluent is considered as an increasing problem and many onsite purification methods have been studied. In this investigation, the method of reactive bed filters have been tested by column and batch experiments. Five different kinds of filter materials with reactive surfaces have been studied concerning their capacity to absorb ammonium and phosphorus from wastewater. The materials that were examined are Filtra N, wollastonite Filtra P, blast furnace slag and Polonite®.

The eutrophication of inshore seas, lakes and watercourses is mainly due to leaching of nitrogen and phosphorus (P) from agriculture. Many efforts are made to reduce the lea-kage of phosphorus in Sweden and the Baltic Sea countries. Phosphorus is also a finite resource and the mining of good quality raw material gets more and more difficult. Se-dimentation dams in combination with filters is one relatively new method to separate P from run-off and drainage water from agricultural land. This study was a part of an IVL Swedish Environmental Research Institute?s project which tests the capacity and func-tion for separation of phosphorus in four phosphorus filters.