CONSTRUCTED WETLANDS SYSTEMS FOR WASTEWATER TREATMENT IN POLAND

Constructed wetland systems for treatment of wastewater from rural aeries could be an interesting alternative for conventional wastewater treatment plant. The objective of this paper was to evaluate the performance and efficiency of organic pollutants removal of hybrid constructed wetlands in the Gdansk region working in temperate climate and under different loadings. Facility consisting of septic tank and vegetated subsurface bed (willow or reed) could be recommended for treatment of wastewater in rural areas. Hybrid Constructed Wetland (HCW) provides efficient and stable both organic matter and nitrogen removal with the efficiency up to 95.7% of BOD5 and 78.0 % of N-Tot. It was indicated that mass removal rates (MRRs) of organic matter (BOD, COD) for analysed HCW were independent of applied configuration in contrast to the MRRs of total nitrogen. The highest MRR of nitrogen (1.06 gNm(-2) day(-1)) was observed for vertical flow beds in Wiklino facility with unit area of 4.0 m(2) pe(-1). There is a farther need to explain the main processes responsible for nitrogen removal and relationship between discharging loads and configurations of hybrid constructed wetlands.