الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Population growth and increased per capita demand, in the face of relatively fixed supply of fresh water, has led to water shortages particularly in arid and semiarid areas. Shortage has begun to occur even in humid regions, particularly in urban areas. Half the world’s population will soon be living in cities. Conservation and demand management are being increasingly adopted but are not adequate to meet increasing demands. For that reason, wastewater treatment is a critical and urgent demand which help to increase the resource of water by reuse of the treated wastewater and also prevent the contamination of aquatic systems (surface and ground) with polluted water.
The major problems likely to arise from sewage effluent discharges are nutrient enrichment (eutrophication) with its associated algal blooms and deaeration of the water course. Nitrogen and phosphorous resulting from sewage discharge are limiting factors for the growth of plants and hence the production of biomass on land and in water ecosystems. Thus control of phosphorous and nitrogen-containing wastewater presents a mean of controlling the deleterious effects of eutrophication. For this reason, several countries apply a phosphorous and nitrogen standards for sewage effluent discharges.
During the present study, primary-treated wastewater samples were collected from the final effluent of the West Wastewater Treatment Plant (WWTP) in Alexandria. Treatment processes include influent screening, grit removal, scum removal, and sedimentation. The plant treat 85 % of the influent total suspended solids, 27 % of total solids, 68 % of BOD and 72 % of COD. The effluent still contain high organic load in addition to phosphorous and nitrogen which have limited removal by the mean of primary sedimentation.
The present study aimed at elimination or minimization of phosphorous and nitrogen to reach the acceptable levels for discharge by law in order to protect the receiving water course (L.Mariut).