Design and Optimization of a Continuous Flow System for the Solar Disinfection of Water, for Use in Rural Communities

The design and optimization of a continuous flow solar water disinfection device is presented. The design is based on a batch disinfector, previously tested and reported, in which water was exposed to solar radiation in plastic bottles. In the new device, water flows through a plastic pipe exposed to solar radiation. The flow control is accomplished by using a solenoid valve, which permits the flow of water only when the solar radiation reaches a minimum predetermined value. In the optimization analysis, the tubing’s diameter and length-width ratio of the irradiation zone were optimized to obtain the maximum flow at the exposure time required to obtain water disinfection. External flat reflecting surfaces concentrate the incoming solar radiation over the receiving area, in order to reduce the residence time required to guarantee complete water disinfection.