Laboratory-scale vertical subsurface flow constructed wetland for pollutant removal using umbrella palm

Constructed wetlands (CWs) are natural wastewater-treatment systems that eliminate contaminants using biological, chemical and physical processes. Vertical subsurface flow constructed wetlands (VSF CWs) can improve oxygen transmission and encourage the microbial breakdown of nutrients and organics. A laboratory-scale VSF CW planted with umbrella palms (Cyperus alternifolius) is used in this study to examine the initial performance of removing total solids (TS), nitrate, phosphate, chemical oxygen demand (COD) and biochemical oxygen demand (BOD). This system demonstrated a progressive rise in removal efficiency over the course of five treatment cycles with intermittent pulsing and a hydraulic retention duration of two days. Around 78% of BOD, 60% of COD, 58% of nitrate, 46% of phosphate and 74% of TS were removed. Statistical analysis using paired t-tests and analysis of variance revealed significant differences between influent and effluent concentrations. Although more research on long-term performance, substrate optimisation and pollutant removal kinetics is advised, these initial results imply that umbrella palm-based VSF CWs may have potential for treating wastewater in tropical environments.