Removal of Pollutants by Different Constructed Rapid Infiltration and Change in Surface Characteristics of Fillers

Abstract

This study was aimed to explore the removal of pollutants by different constructed rapid infiltration (CRI) and change in surface characteristics of fillers. The result showed that the increase of filler height and mechanical ventilation was beneficial to the removal of COD by CRI, but not to the removal of SS;the increase of filler height was beneficial to the removal of most heavy metals, and the effect of mechanical ventilation on the removal of heavy metals was very small. Found by SEM, the biofilm on CRI fillers decreased gradually along the direction of water flow, mechanical ventilation increased the biofilm on CRI filler at 0.8 m, but decreased the biofilm on CRI filler at 1.3 m. Found by the element analysis of EDS, the main elements on the surface of three groups of CRI filler were O, C and Ca, in addition, P, S, Cl, As, Cd and Hg were also included; the composition of elements on the surface of three groups of CRI fillers changed little along the direction of water flow, but the proportion of elements changed constantly along the direction of water flow; the height of filler and mechanical ventilation had little influence on the composition of elements on the surface of CRI fillers, but had a certain influence on the proportion of elements.