Evaluation of the effectiveness of phytoremediation technologies utilizing Lemna minor in constructed wetlands for wastewater treatment

Phytoremediation is a cost-efficient process for removing contaminants from wastewater, soil, and sediments. This study used Lemna minor in a vertical subsurface flow system to treat wastewater at the Al-Muamirah facility in Babylon, Iraq, by evaluating the biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS) from 31 October 2023 to 14 March 2024 using batch-mode wastewater input. The mean influent flow rate was 0.05278 m³/day ± 0.015 m³/day with a detention time for all parameters of 5 days, except for the nitrate parameter (TN and TP) examinations equal to 8 days. A VF basin was also used for comparison. Results showed that Lemna minor’s removal efficiencies for BOD, COD, TN, TP, and TSS were 93.26, 84.87, 70.58, 71, and 83.73%, respectively. The VF unit showed lower removal values but still performed effectively. These findings highlight the potential of Lemna minor for efficient and sustainable wastewater treatment, especially in areas with limited access to conventional wastewater treatment technologies.