Optimal Coagulation/Flocculation Process For Water Treatment Plants Located On Damietta Branch Of River Nile, Egypt

A coagulation-flocculation process, using three different phases of aluminum derivatives, namely; Alum Al2(SO4)3.18H2O, Poly-aluminum chloride (PAC) (Al2(OH)xCl6-x)n; Potassium aluminum sulfate (PAS) KAl(SO4)212H2O 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, coagulation/flocculation, filtration and disinfection which didn't 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 coagulant's doses relative to Zeta potential have been studied to find out the optimal operating conditions.