EVALUATION OF THE PERFORMANCE FOR THE WASTEWATER TREATMENT PLANT THROUGH MEASURING PHYSICAL AND CHEMICAL PARAMETERS

Domestic sewage treatment plant at Suez consists of both primary treatment ponds(mechanical step)where the large particles was removed and secondary treatment ponds .The water samples were collected from different stages of domestic sewage treatment plant during the period from March 2003 to February 2004,from locations influent sewage water(A),aerated lagoon(B),facultative lagoon(C) and effluent water( D). The data obtained indicates that, the suspended solids (SS) values decrease as going from location A(influent) to location D(effluent) during almost all seasons. This finding shows that the effluent of domestic sewage after passing through primary treatment stage it has been clarified. Seasonal variation of dissolved oxygen contents are fluctuated between the lowest values of 0.74 mg/L at location A in autumn 2003and the highest value of 5.48 mg/L at location D in winter 2004. On contrary, the minimum biological oxygen demand (BOD) value was 150mg/L recorded at location D in winter 2004, while the maximum value was 979 mg/L at location A in Autumn 2003. The chemical oxygen demand(COD)contents at the domestic sewage treatment plant are in harmony with the biological oxygen demand (BOD)values as indicated from a high significant correlation coefficient(r =0.979,P≤ 0.05)between them. Furthermore, secondary treatment will reduce effluent BOD, COD and pathogen contents. Removal percents of sulphide ion from location A to location D at domestic sewage treatment plant were 30%,9.07%,6.06% and 6.52% recorded during Spring2003,Summer2003,Autumn2003 and Winter 2004, respectively. Similarly, removal percents of ammonia concentrations are varied from a higher value of 36.36% recorded during spring 2003 to a lower of 3.53% recorded in autumn 2003. On the other hand, the maximum concentration of reactive phosphate in the domestic sewage was 4.61 mg/L recorded at location A in Autumn 2003as the result of use the detergents in house.