Acid Mine Drainage Treatment with Organic Waste in Constructed Wetlands – Effluent Recirculation.

Vertical subsurface flow constructed wetland (VSSF-CW) was evaluated to neutralise acid mine drainage (AMD) using organic waste and planted with mangroves. The type and composition of media, as well as the improper assembly and operation of the system, are among the reasons why the wetland system has not been effective and efficient so far. The main objective of this research is to develop a method to neutralise AMD using organic waste (oil palm empty fruit bunches and eucalyptus leaf waste). To achieve this research’s main goal, the steps were to analyse the characteristics of AMD at the research site, analyse the type and composition of organic waste, determine the retention time, and analyse the concentration of contaminants in the water after the treatment process. To implement the stages, sample preparation, plant acclimatisation, organic material selection, primary characterisation of samples, assembly of the CW reactor, and operation of the system were carried out. After the study, it was found that the system maximally increased the pH from 3.32 to 7.34 in the 12-day retention time oil palm empty fruit bunches reactor, and maximally removed total suspended solids (TSS) and manganese (Mn) with efficiencies of 97.52% (from 444 to 11 mg/L); and 95.97% (from 4.47 to 0.18 mg/L) in the 12-day retention time eucalyptus leaf waste reactor, respectively. Rhizophora sp. showed bioaccumulation ability > 1 (accumulator) and translocation < 1 (phytostabiliser). The media type and composition, as well as the assembly and operation of the system in this study successfully neutralised AMD with good efficiency and a relatively short time. In addition, the addition of mangrove plants and fly ash-bottom ash (FABA) bricks, also contributed to the good results of AMD treatment and also became an innovation in AMD treatment. [ABSTRACT FROM AUTHOR]