No abstract

International audienceThe use of sand of dunes as a filtration support for domestic wastewater treatment demonstrated its efficiency at pilot scale. However, the filter receives non negligible amounts of suspended matter, leading to biological clogging owing to the colonization of the pores of the filtration media by biomass and related by-products. Fouling time-course was examined in this work. Measurements carried out at various column heights showed that the difference of porosity between the first and last layers can reach 2%, while the decrease between the initial and the final state was above 7% for all layers. Organic matter accumulation followed similar history than fouling, showing its involvement in the process and its preponderance in the fouling mechanism if compared to mechanical fouling. The amount of organic matter was mainly apparent in the two upper layers of sand and exceeded 2% in the first sand layer after 7 day