THE REMOVAL OF PHOSPHORUS FROM CONSTRUCTED WETLANDS

This article discusses phosphorus precipitation in constructed wetlands, which are effective at removing pollutants from wastewater, except for phosphorus. The PAX-18 coagulant was used to enhance phosphorus removal. Precipitation equipment was installed in three wetlands, each with different technological arrangements. In two of the wetlands, a gradual dosing of coagulant was implemented, while in the third, a single dose of 200 litres was applied. Dosing was based on the average phosphorus influx, with samples taken at various intervals and analysed in the laboratory using cuvette tests. In the first constructed wetland, the average concentration of total phosphorus in the precipitation section was 1.8 mg ? L-1 lower than in the section without precipitation, representing a 28% increase in efficiency. In the second wetland, the total phosphorus concentration was 1.0 mg ? L-1 lower than during periods without precipitation. In the third constructed wetland, the concentration of total phosphorus decreased by 0.2 mg ? L-1 due to phosphorus precipitation, while the average concentration of total phosphorus discharged from the wetland was 0.05 mg ? L -1, resulting in an overall efficiency of up to 98%. As phosphorus is a biogenic element, its concentration in the aquatic environment, exacerbated by climate change, causes major problems, such as eutrophication. Therefore, it is crucial to begin effectively removing phosphorus from wastewater.