Effective Removal of Biogenic Substances Using Natural Treatment Systems for Wastewater for Safer Water Reuse

Natural Treatment Systems for Wastewater (NTSW) show great potential for economic, socially acceptable and environmentally friendly wastewater treatment, along with the renewal of water for its safe reuse. This article presents the reduction in nitrogen and phosphorus compounds in domestic wastewater, which was achieved in a 2.5-year operation of the newly developed NTSW. The presented installation was developed by the Institute of Applied Ecology in Skórzyn (Poland) and implemented as a pilot plant serving the institute building with three permanent residents and up to five employees. The installation consisted of two parts, responsible for: wastewater treatment (septic tank and compost beds) and water renewal (denitrification beds, phosphorus beds and activated carbon beds). The mean values of nitrogen and phosphorus compound concentrations obtained in the renewed water for the entire research period were: 0.8, 49.4, 12 and 3.1 mg/L for ammonium nitrogen (NH4), nitrates (NO3), total nitrogen and phosphates (PO4), respectively. Thus, average reductions of 99.6%, 90.9% and 94.4% were obtained for NH4, total nitrogen and PO4, respectively. Treatment of domestic sewage to such a level, similar to drinking water, enables versatile, safe water reuse, which in the situation of increasingly limited water resources will constitute increasing ecological and economic value.