Influence of the aeration of the filter bed on the purification performances of infiltration-percolation process
Infiltration-percolation is an extensive process for the treatment of urban wastewater, allowing the degradation of organic matter and the oxidation of nitrogen. The main objective of this research is to investigate the influence of the aeration of the filtering mass on the purification performances of the infiltration-percolation process. The results of analyzes showed that the laboratory columns equipped with aeration systems favored the best abatement rates of organic and nitrogen pollution. The organic matter expressed in terms of COD (chemical oxygen demand) was removed at 58.35% and 81.11%, respectively, for the infiltration column without and equipped with a central and peripheric aeration system. The abatement efficiencies of ammoniacal nitrogen were 74.11% and 92.14%, respectively. The experimental results also showed that the oxidation capacity of the filter depends on the reoxygenation of the filter bed. Over the renewal of the gas phase of the porous medium is provided, the better the oxidation capacity.