EFFICACY OF CANNA LILY AND CYPERCUS ALTERNIFOLIUS TOWARDS THE REMOVAL OF PHOSPHATE FROM WASTEWATER USING A CONSTRUCTED WETLAN

Abstract

Considering the extensive eutrophication of water bodies, sustainable treatment techniques such as constructed wetlands (CWs) have emerged as a possible alternative for nutrient removal and wastewater treatment. The present study was undertaken to investigate the potential of Canna lily and Cyperus alternifolius based CW for removal of phosphate (PO4 3- -P) in different seasons of a sub-tropical region. During the current study, the intake phosphate concentration was taken as roughly 5 mg/l. As a result, in the present study, removal efficiency for total phosphate (TP) in Canna lily followed the trend of winter season (77.56 %) < spring season (82.61 %) < summer season (87.79 %). The removal efficiency of Cyperus alternifolius CW cell was of order winter season (62.35 %) < spring season (74.24 %) < summer season (81.49 %). C. lily TP effluent concentrations throughout the study ranged from 0.18 mg/l to 1.82 mg/l while the average TP effluent concentrations in C. alternifolius ranged from 0.33 mg/l to 2.65 mg/l. The accumulation of (TP) in various parts of plant tissue were investigated in order to determine the overall effect on the plants during the study period. The concentration of PO4 3- -P (mg/g) in roots, stems, leaves, and flowers has been analyzed. The effluent pH (6.2-8.3) was in the neutral range, and oxidising conditions in the rhizosphere ruled out the possibility of phosphate bonding with cations (Ca, Fe, and Al) in sediments. Evapotranspiration, plant metabolic activity, and hence nutrient removal were all influenced by ambient temperature and sunlight hours.