economic study on the appilication of starch as a coagulant - aid in water treatment

iran, for it's socio-economic development is faced with limitations, because of growing population, economic drawbacks and shortcomings in resources. therefore, country planning should be based on considering the limitations. at present, water treatment industry in iran is regarded as one of the major development activities needing a comperehensive management with both quantitative and qualitative approaches. in this paper, emphasis has been placed on the evaluation of the application of starch as a natural organic polymer in turbidity removal , due to the shortage and the high price of some coagulants. also the effectiveness of starch was compared with imported synthetic polyelectrolytes. in this research, following the determination of the starch optimum dosage in turbidity removal in different conditions, economic evaluation was done on the cost of the chemicals (alume, ferric chloride and starch). then, regarding the number and the capacity of water treatment plants (wtps) in iran, which use alum and ferric chloride as coagulant, the annual cost savings of 6/878/933/300 rials in water treatment industry in the case of starch application was resulted.