PHYSICOCHEMICAL CHARACTERISTICS OF RAW SEWAGE IN OUJDA (MOROCCO)

The goal of this study is to characterize the effluent of the city of Oujda (Morocco) and to evaluate its pollution in relation to the demographic and socio-economic profile of the population connected to the sewerage in order to make the possibility to reuse it in irrigation. The physicochemical characterization of raw wastewater revealed that this liquid rejection is very charged out of organic matter expressed in term with COD (Avg. = 1104mg/L±52,2) with a load of 44160Kg/d, in BOD5 (Avg. =540,1mg/L±31,1) with a load of 21604 Kg/d, in Suspend Solid (Avg. =568,4mg/L±222) with a load of 22736 Kg/d, and out of mineral matter expressed in Electric Conductivity (Avg. =3280μS/cm±1120) with a pH of 7,96 (±0,8). The average content of NTK and Orthophosphates are about 88,02mg/L (± 2,8) and 16,76mg/L (±1,1). Although this wastewater presents a high organic load BOD5/COD = 0,5 et SS/ BOD5 = 1,05), they have a satisfactory biodegradation. The examination of report COD/BOD5 = 2,07 underlines well the biodegradable character to which a biological treatment appears completely suitable.