USING SUNLIGHT TO CLEAN WATER

LAURENCE GILL

Water-related diseases account for the majority of premature deaths in sub-Saharan Africa and other developing parts of the world which, in many cases, could be alleviated by the provision of an adequate supply of water for both drinking and washing. In such situations there are often neither the finances nor the resources to construct and maintain the types of water treatment processes used in more industrialised countries which tend to be both energy and chemical intensive. Sunlight can be used to destroy disease-causing pathogens in polluted drinking water, with ultraviolet radiation and solar heat disrupting their metabolism and cellular structures. This project demonstrates the principle of a continuous flow solar disinfection and arsenic removal system technology that has been developed in Trinity College Dublin to produce clean water supplies at a village-scale in developing countries. The basic principle of the system involves water flowing through a transparent pipe at the focal point of a compound parabolic reflector, optimally angled beneath the pipe for maximum sunlight capture.