Sustained Phosphorus Removal by Calcareous Materials in Long-Term (Two Years) Column Experiment

(1) Phosphorus (P) removal has proven difficult in decentralized wastewater treatment systems, and external filters installed with a highly P sorbent material have been proposed to improve the removal. In particular, calcium (Ca) rich materials shown promising results. (2) Eight (five calcareous materials, one quartz sand, two Sol–Gel coated materials) were tested columns fed P-spiked tap water for years. The experiment was operated under four periods increased concentration from 3.3 21.5 mg L−1, surface loading rate 18 227 mm d−1. After termination, element content measured column height fractions. (3) Initially, all removed effectively (CAT, CAT A, C) maintained an effective until while increases effluent detected already after 7 weeks SAN 80–90 OPO, PHO, CAL, HYG. highest bottom fraction closest inlet distribution. For most we observed good agreement between maximum sorption capacity (Qmax) fraction; however, discrepancy C. (4) conclusion, provided consistent 24 months. Additionally, coating had minimal effect on contrary previous findings batch experiments materials.