Effect of feed pattern of landfill leachate on water reduction in constructed wetland in Southeast Asia

To improve landfill management in Southeast Asia, reduction of landfill leachate volume with low cost and easy operation is required. The present study attempted to utilize constructed wetland (CW) for reduction of landfill leachate by evapotranspiration. The objective of this study is to evaluate the influence of operation and season on evapotranspiration of CW applied to landfill leachate treatment in tropical regions. The pilot-scale CW planted with cattail was constructed in Sainoi landfill site, Thailand. CW could siginificantly reduce the leachate volume by the evapotranspiration in daytime than nighttime. Frequent inflow of horizontal subsurface flow (HSSF) during daytime resulted in active evapotranspiration. Evapotranspiration of CW in HSSF with high frequency of inflow showed the similar that in free water surface (FWS). Throughout the year including both rainy and dry seasons, evapotranspiration of CW were significantly higher than the evaporation volume which is regarded as water reduction by existing landfill leachate treatment, i.e. stabilization pond. CW should be served as the techonology for appropriate management of landfill leachate in Southeast Asia.