Screening of low-cost waste materials for removal of phosphorus from wastewater in Constructed Wetlands

Abstract

The phosphorus (P) removal performance of Constructed Wetlands (CWs) depends on the utilization of suitable material as the substrate. In this study, the focus has been drawn on the screening, leading to the use of waste materials for removal of P from wastewater in CWs, which will have an additional benefit of reuse to promote sustainability of resources, by reducing the amount of solid waste for disposal. Studies have been carried out to examine the physicochemical properties of low-cost waste materials and their preliminary phosphorus (P) adsorption capacities. Five construction waste materials have been investigated marble, tile, granite, sanitaryware, and autoclaved aerated concrete as substrates for CWs, for removal of P.Based on the physicochemical properties and preliminary phosphorus adsorption capacity measurement, autoclaved aerated concrete and tile waste showed potential as filler media in CWs. But leaching experiment for AAC showed TP leaching potential as 0.058 mg/g which is an undesired property in filler media for CWs. Therefore, it cannot be considered for use as a component of the substrate matrix. Though the physicochemical properties of other materials were suitable for use as filler media, their adsorption capacity in the preliminary P adsorption test was less. The potential for P adsorption was in the order autoclaved aerated concrete > Tile > Granite > Marble > Sanitary. The precursory screening assay of new materials is important before undertaking laborious and intricate research studies.