Phytoremediation of Nitrogen and Phosphorus in Municipal Wastewater by Cyperus alternifolius Planted Constructed Wetland

Introduction

Municipal wastewater fundamentally divided into two types black water and gray water. Gray water is from kitchen wastewater, sink, washing machine and bathroom. This wastewater can reach up to 75% of the total wastewater generated in the household (Hernández et al., 2011). Black water comes from toilets with high concentrations of nitrogen and phosphorus (Zeeman et al., 2008). This kind of domestic wastewater should be considered as one of critical environmental problem since through the quality and quantity, it can contaminate the environment, interfere human health and other creatures. An increasing number of domestic wastewater causes negative impact on environment quality since it generally discharge directly to natural water like as river and lakes so it can cause increasing pollutant load on the water bodies. Constructed wetlands provide a greater level of pollutant control to discharge effluent to surface waters (Kadlec & Wallace 2008). The sewage discharge from the domestic sewage treatment plant is typically subjected to the local, state and federal regulations and standards. In December 2009, the Department of Environment (D.O.E) Malaysia has revised the Environmental Quality (Sewage) Regulations 2009, which significantly reduced the discharge limit of ammonia-nitrogen from 50 mg/L to 5 mg/L. In addition, a new discharge limit was also set for nitrate at 10 mg/L (Kutty et al., 2011).