Comparative evaluation of ditch filters with phosphorus sorbing calcium based filter materials

Abstract

The aim of this paper was to evaluate the sorption capacity of calcium based filter materials (Polonite, Filtralite P and Hyttsand) under Lithuanian conditions. The results obtained from 16 months long ditch filters investigations showed that the efficiency of tested filter materials varies from 60 to 30 % on the average. The filter material Polonite was distinguished by highest reduction capacity of phosphorus, slightly less reduction was determined using Hyttsand and the least using Filtralite-P. The monitoring results confirmed that ditch filters have some ability to the retention of phosphorus and water purification. In total, ditch filters adsorbed about 96–208 g total phosphorus (TP) and 20–124 g phosphate phosphorus (PO4-P) during the reporting period (January 2013 – May 2014).