Impact of Mass Loading Rate and Vegetation on the Performance of Horizontal Subsurface Flow Constructed Wetlands (original) (raw)

Abstract

ABSTRACT Constructed wetlands (CW) are sustainable wastewater treatment processes, especially for small communities. In order to evaluate the effect of mass loading rates and the presence of plants on the removal of organic matter and ammonia in horizontal subsurface flow CW, two set of experiments were carried out at different organic and ammonia loading rates in two mesocosms, one without plants, other colonized with Phragmites australis. Regardless the mass loading rates, the COD removal was significantly greater in the bed containing plants (70.3% and 75.6%, respectively, for the lower and the higher organic loads) than in the bed without plants (38.5% and 44.4%, respectively). The removal of NH4-N was also significantly higher in the planted bed (59.3% and 47.8%, respectively, for the lower and the higher nitrogen loads) than in bed without plants (34% and 33%, respectively). The removal of organic matter and ammonia was higher in the first section of the bed (first 33 cm) in the unplanted system (> 75%) and was more distributed through the bed in the planted system, which seems to have been associated with the growth of roots and rhizomes that support the biofilm as well as the release of oxygen in the root zone.

Leonor Amaral hasn't uploaded this paper.

Let Leonor know you want this paper to be uploaded.

Ask for this paper to be uploaded.