Evaluation of living Azolla filiculoides performance for the removal of total nitrogen, phosphorus, sodium, potassium, COD, BOD, and TDS from dairy waste: Full factorial design

In this study, the potential of living Azolla filiculoides was investigated to treat dairy wastewater. The full factorial design was performed to evaluate the effect of contact time, pH, and temperature on the removal of total nitrogen, phosphorus, sodium, potassium, chemical oxygen demand (COD), biological oxygen demand (BOD), and total dissolved solids (TDS). At the contact time of 6 h, the removal efficiencies of 74.67% and 28.78% have been observed for sodium and TDS, respectively. Also, the removal efficiency of 59.20% has been obtained for phosphorus at the contact time of 18 h. The results indicated that Azolla filiculoides can be used successfully as an effective adsorbent for sodium and phosphorus removal.