Analysis of roof and bottle combinations for disinfection using the SODIS methodology

Abstract

In Latin American countries, alternative methods of water disinfection have been positioned as a variant for the supply of drinking water to communities of limited resources. However, their application is affected by a lack of access to the necessary materials and equipment. In the case of the solar disinfection of water (SODIS) method, some materials used have a high cost. In this paper performed the analysis of a combination of roofing materials and bottles subjected to solar radiation and its function as easily accessible disinfectants materials for communities of limited resources to ensure effective disinfection at low cost and provide suitable drinking water for those communities.  For this research, rainwater was collected, then it was subjected to a disinfection process by means of solar radiation, using the SODIS methodology. The study used bottles of two materials, the first was polyethylene terephthalate (PET) and other glass. Both bottles were exposed to solar radiation on two different roofing materials, one steel sheet and the other clay tile. In this study a removal efficiency of total coliforms was in the range from 25% to 50%, and a removal efficiency of fecal coliforms was in the range from 53% to 88%; in both cases with an exposure to sunlight of 6 hours. The combination that achieved the best removal efficiency of total and fecal coliforms is the combination of a steel sheet and PET bottles.