New intake control system based on river water quality.

The authors propose a new intake control system for water purification plants based on river water quality. In this system the intake flow rate of a plant will decrease while the river water is polluted, whereas it will increase after the water quality of the river has recovered. The purpose of this system is to reduce the operational costs of water purification while securing an adequate water supply. Simulation studies on the proposed system were conducted to investigate the reduced amount of coagulant dosage and waste sludge generated. Simulation results with 2-year, on-line turbidity data revealed that the reduction percentages of waste sludge for the first and second years were 5.8% and 8.5%, respectively. This remarkable effect suggests that the proposed system could also contribute to enlarging the capacity of landfill sites for incinerated sludge and to preserving the environment.