Reduction of COD and Ammoniacal Nitrogen from Stabilized Landfill Leachate by Using Green Mussel and Zeolite as Composite Adsorbent.

Landfill leachate is a liquid generated due to rainwater percolation through the waste in a landfill or dumping site that may contain high levels of organic matter including both biodegradable and non-biodegradable which are the major sources of water pollution. Chemical oxygen demand (COD) and Ammoniacal Nitrogen (NH3-N) contents have been relevant indicators of severity and pollution potential of landfill leachate. The reductions of COD and NH3-N were investigated in this study using different combination media ratios of green mussel (GM) and zeolite (ZEO). Generally, zeolite is considered as a renowned adsorbent but relatively very high in cost. In Malaysia, mussel shell is abundantly available as a by-product from the seafood industry and is regarded as waste and mostly left at dumpsite to naturally deteriorate. Its quality and availability make the green mussels a cost-effective material. In this research study, leachate samples were characterized and found to contain high concentrations of COD and NH3-N. The adsorption process was conducted to find out the best combination media ratio between GM and ZEO. The removing efficiency was determined at different amounts of composite media ratios. The optimal adsorbent mixture ratio between (GM: ZEO) of 1.0:3.0 and 1.5:2.5 were considered as a more efficient technique in removing COD and NH3-N compared to exploiting these adsorbents individually. The optimal extenuation removal reduction was found at an approximately 65% of COD and 78% of NH3-N. The adsorption Isotherm Langmuir model exhibited a better fit with high regression coefficient for COD (R2 = 0.9998) and NH3-N (R2 = 0.9875) respectively. This means that the combination of GM: ZEO adsorption of landfill leachate in this analysis is homogeneous with the monolayer. The mixture of green mussel and zeolite was observed to provide an alternative medium for the reduction of COD and NH3-N comparatively with lower cost.