Removal of Natural Organic Matter (NOM), Turbidity, and Color of surface water by integration of enhanced coagulation process and direct filtration

Document Type: Original Article


1 MSc. of Environmental Health Engineering, Shahrekord University of Medical Sciences, Shahrekord, Iran

2 Department of Environmental Health Engineering, School of Public Health, Shahrekord University of Medical Sciences, Shahrekord, Iran

3 Environment Research Committee, Isfahan University of Medical Sciences, Isfahan, Iran, Student Research Committee and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran


This work assesses the efficiency of integrated enhanced coagulation and direct filtration processes for the removal of color, turbidity, and natural organic matter (NOM) from surface water. The processes were conducted in a simulated pilot. The operating conditions of the treatment process, including pH, FeCl3 dose, and influent flow, were investigated. Following that, its efficiency was evaluated by measuring specific water quality parameters in the output stream including NOM, turbidity, and color. The results showed that under optimum conditions (pH, FeCl3 dose, and influent flow of 6.2, 95 L/h, and 40 mg/l, respectively), the color and turbidity were removed 96% and 95% respectively. According to factors analysis by the Taguchi method, the influence of these factors on the removal of pollutants decreased as follows: pH → FeCl3 dose → influent flow. The results revealed that the integrated enhanced coagulation process and direct filtration can improve the efficiency of colors, turbidity, and NOM removal in water treatment plants.


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