TEMPORAL VARIATION OF THE DUCKWEED EFFICIENCY IN WASTEWATER TREATMENT

Wastewater originates from commercial, industrial and domestic sources that represent the largest volume. The quality of wastewater is linked to human behaviors and habits which represent a high risk to our planet so it must be treated to dispose it safely. The main objective of this study is to treat the domestic wastewater using Duckweed pond (DW) for reuse again. All experiments were conducted outdoors at the faculty of PSAS, Beni-Suef University. Duckweed pond was fabricated from glass material with 200Liter effective volume and continuously fed with domestic wastewater at different flow rates 15 and 10 days. Total 32 samples (16 for influent and 16 for effluent) in each season were collected and analyzed to evaluate the efficiency removal across the experimental system. The obtained results show that the treatment efficiency of DW at summer season was significantly higher than that of winter season for TDS, EC, TS and NH3 at p˂ 0.05. The system achieved 28, 28, 57, 57, 40.8, 83.8, 46.4, 91.4 and 79% removal efficiencies for TDS, EC, COD, BOD, TOC, TSS, TS, NH3 and TP respectively. Nitrate and nitrite values increased at the effluent in comparison to the influent but nitrate value decreased in the effluent at 10 days HRT by 84% during winter season. Duckweed plant successfully can be used for removing wastewater pollutants and improve the wastewater quality.