Phytoremediation performance of Acorus calamus and Canna indica for the treatment of primary treated domestic sewage through vertical subsurface flow constructed wetlands: a field-scale study

Under the present investigation, vertical subsurface flow constructed wetlands (VSSFCWs) planted with macrophytes treated domestic sewage in an environmentally sustainable manner. Treatment of domestic sewage with wetlands is an alternative method that decreases energy consumption and economic costs involved in the treatment of environmental contaminants. This study evaluates the potential efficiency of VSSFCWs using two different macrophytes, Acorus calamus and Canna indica for the treatment of domestic sewage. To perform this study, two chambers of VSSFCWs of dimensions 2.48 m × 1.24 m × 1.54 m were built. The wetland was fed with the primary treated sewage at a hydraulic loading rate (HLR) of 0.67 m3/h (hours) in a batch flow. Treatment of primary sewage was observed from day 1 to day 6; once a day (i.e. 24 h to 144 h). The treatment of sewage was found to be significant up to day 6 (144 h); beyond this time, no significant removal was observed. The results revealed that both the wetland setups performed significant removal of TDS, BOD5, total nitrogen, and phosphate. The wetland planted with Canna indica was a better performer for the removal of TDS (22.31%), BOD5 (81.79%), total nitrogen (60.37%), and phosphate (80%).