Treatment of organic pollution of domestic wastewater by infiltration-percolation process on two types of titaniferous sands: Gross and sieved [Traitement de la pollution organique des eaux usées domestiques par le procédé d'infiltration-percolation sur deux types de sables titanifères: Brut et tamisé]

Environmental problems related to chemical and biological pollution of domestic wastewater require pretreatments to avoid any health problems. the treated wastewater may constitute a water supply for irrigation of public parks,golf courses and groundwater recharge. several techniques are used for the purification of domestic wastewater,our work is based on the infiltration-percolation technique,which is a biological treatment process with a culture fixed on thin media. it consists of percolating water to be treated on the gravel pack (titaniferous sand) until reaching a drainage system. this study evaluates the purifying power of two types of titaniferous sand (gross (gts) and sieved (sts)) of agadir city. the efficacy of this purification technology is the study of a number of physico-chemical parameters of wastewater before and after treatment (cod,bod5,...). the results show the same performance for bod5 (biochemical oxygen demand) for both types of titaniferous sand,which can reach 99% in contrast to the other parameters that had known an excellent performance for sts. indeed,for cod (chemical oxygen demand) we have 90% with gts and 94% with sts,and concerning the turbidity we have 91% with gts and 96% with sts.