Optimal CoagulationFlocculation Process For Water Treatment Plants Located On Damietta Branch Of River Nile Egypt

ABSTRACT A coagulation-flocculation process using three different phases of aluminum derivatives namely Alum Al2SO43.18H2O Poly-aluminum chloride PAC Al2OHxCl6-xn Potassium aluminum sulfate PAS KAlSO4212H2O have been studied respectively. Optimum operating conditions have been established to achieve the optimal parameters and to achieve the maximum removal of pollutants in the constructed water treatment plants. River Nile Egypt is the main source for drinking water and major other activities. Nile water contains suspended solids and colloidal particles that are normally treated by coagulation-flocculation followed by clarification. Alum PAC and PAS have been studied to establish the optimum suspension removal which are the most common types of coagulants in water treatment plants in Egypt as well in many other countries. Coagulants were investigated with the aim of determining their capabilities to reduce turbidity and other contaminants in drinking water to the required drinking standards. In Egypt conventional drinking water treatment plants are including pre-chlorination coagulationflocculation filtration and disinfection which didnt improve the utilization of coagulation that led to high consumption of coagulant and coagulant aid pH adjustment high residual aluminum high cost treatment and mass production of sludge. The effect of seasonal variation including temperature pH fluctuation alkalinity pre-chlorination and coagulants doses relative to Zeta potential have been studied to find out the optimal operating conditions.