Mokhtar Mahdavi - Environment Research Center, Isfahan University of Medical Sciences, Isfahan, Iran, and Student Research Center and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
Afshin Ebrahimi - Associate Professor, Environment Research Center, Research Institute for Primordial Prevention of Non -communicable disease, Isfahan University of Medical Sciences, Isfahan, Iran, & Department of Environmental Health Engineering, School of Health, Isfahan
Ensiyeh Taheri - Environment Research Center, Isfahan University of Medical Sciences, Isfahan, Iran, and Student Research Center and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
Ali Fatehizadeh - Environment Research Center, Isfahan University of Medical Sciences, Isfahan, Iran, and Student Research Center and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran

Background & Aims of the Study: In some situation like rainfall seasons raw waterbecome very turbid so it affected the water treatment plant processes and quality of producedwater. Treatment of very high turbid water has some concerns like precursors for disinfectionby-products and very loading rate of particle on filter s media and consequently increases inwater consumption for filter backwash. This paper investigates the performance of acomposite inorganic polymer of aluminium and ferric salt, Polyaluminium ferric chloride(PAFCl), for the removal of turbidity, color and natural organic matter (NOM) from highturbid water.Materials & Methods: Experiments were carried out by Jar test experiment by syntheticwater samples with 250 and 500 NTU turbidity that prepared in laboratory.Results: The results of conventional jar test showed that the optimum pH for coagulation ofwater sample was 7.5 to 8 and optimum dosage of the coagulant was 10 mg/L. Removalefficiency of turbidity, color and UV adsorbent at 254 nm at optimum dose and pH withoutfiltration was 99.92%, 100% and 80.6% respectively for first sample (250 NTU) and 99.95%,99.49% and 84.77 for second sample (500 NTU) respectively.Conclusions:It concluded that polyaluminium ferric chloride has a very good efficiency for the removal ofturbidity, color and organic matter in high turbid water. Also it can be select as a coagulantfor high turbid water and some waste water from water treatment plant like filter backwashwater.

coagulation, high turbid water, polyaluminum ferric chloride, water treatment