The feasibility of combined coagulation flocculation and constructed wetland as green technology for sustainable leachate treatment

Abstract

This study aims to determine the feasibility of coagulation flocculation processing using Moringa oleífera seed powder (MOSP) and vertical sub surface flow constructed wetlands (VSSFCW) to process leachate landfill (LL). The method used is to do a jar test to determine the optimum conditions and then proceed with VSSFCW processing. In the coagulation flocculation process, the optimum conditions were obtained with a dose of 175 mg/L, pH 6.5 and a speed of rapid mixing of 100 rpm for 10 minutes. This optimum condition is able to reach the percentage of COD, turbidity and Mn removal of 35.27%, 69.48%, and 94.83%, respectively. However, the effluent value is still above the Minister of Environment regulation standard No. 5/2014 regarding the standard quality of wastewater for the parameters of COD and Mn that is equal to 584.19 mg/L for COD and 6.98 mg/L for Mn, while for turbidity meets the standard of 69.83 mg/L. Further processing with VSSFCWs can improve the quality of LL effluent resulting from coagulation flocculation 66.36 mg/L; 4.97 mg/L for turbidity and 0.12 mg/L for Mn or with efficiencies of 88.64%, 92.88% and 98.22%. These results were obtained at the optimum HRT conditions for 10 days.