Phytoremediation of Palm Oil Mill Final Discharge Wastewater using Aquatic Macrophytes Leersia oryzoides, Pistia stratoites and Ludwigia peploides
This study aimed at evaluating the performance of aquatic macrophytes to treat palm oil mill final (POM) discharge wastewater. Samples of POM final discharge wastewater were obtained from palm oil mill of KL Kepong Berhad in Changkat Asa, Tanjong Malim, Perak. Three aquatic macrophytes, Leersia oryzoides (rice cutgrass), Pistia stratoites (water lettuce) and Ludwigia peploides (water creeping primrose) were planted into 6L opentopped containers filled with POM final discharge wastewater. The removal efficiency (%) of BOD5 , COD, NH3-N, metal content and macrophytes’ mass were examined in order to evaluate the phytoremediation performance. The results showed that BOD5, COD and NH3-N removal efficiencies of 93%, 30% and 82%, were achieved for Pistia stratoites, 90%, 27% and 80%, for Lersia oryzoides and 93%, 20% and 80%, for Ludwigia peploide, respectively. In addition, Pistia stratoites and Leersia oryzoides were able to reduce the calcium (Ca) content by 92% and 87%, respectively while there is no significant difference in absorption of other metals like cadmium (Cd), sodium (Na), iron (Fe), and manganese (Mn). Throughout the study, increase in plant weight was observed. These results suggest that the studied aquatic macrophytes are capable in degradation of the organic and inorganic pollutants from POM final discharge wastewater.