Efficiency of Filters Filled with Rockfos for Phosphorus Removal from Domestic Sewage

The goal of the present study was to evaluate the efficiency of filters filled with Rockfos for removal of phosphorus (Total-P) from domestic wastewater using, Rockfos is a material obtained by calcination of carbonate-silica rock (opoka) at a temperature of 900 °C. A field study was conducted in two filters with volumes of 2.0 and 0.8 m3 which were components of hybrid constructed wetlands with an average capacity of 2.0 m3/L, located in two national parks in south eastern Poland. Samples of the influent to and the effluent from the filters were analyzed for Total-P concentrations and pH. Eighty sewage samples were tested over a five year study period. It was shown that the test filters removed Total-P with an average efficiency of 31.5% and 30.2% and that they could be successfully used to remove P from domestic wastewater in small wastewater treatment plants.