Partially saturated vertical-flow constructed wetland with
trickling filter with filtration and chemical precipitation hybrid
system was developed in order to improve denitrification and
dephosphatation as compared to conventional vertical flow constructed
wetlands (VFCW) in a municipal wastewater [57]. For
chemical precipitation, ferric chloride (FeCl3) was added for
phosphorus treatment. Results revealed good performances of the
overall treatment where most of the dissolved carbon and nitri-
fication were removed by trickling filter. The main part of the
treatment was from the first stage known as filtration unit. Nitrate
removal was achieved principally at the second filtration stage.
Phosphorus migration through the first stage and its slight
retention at the second stage was observed.