Opções de tratamento de águas pluviais em sistemas de captação residenciais

Abstract

Water is an essential resource, needed for human survival. Nevertheless, it is not always readily available for everyone. Human population growth, limited water resources and deficient water supply services are part of the problem. To mitigate this, alternative sources of water supply for buildings can be used, including rainwater. To use rainwater in buildings, it is necessary to compare its quality with some recommended or proposed standards, according to the intended uses and, if necessary, subject the water to treatment processes. Different techniques for treating rainwater harvested in buildings, along with their respective studies, have been used as an interesting solution to reduce the problem of water supply in hydrologically depleted regions. In this study, we analyzed the different methods used for water treatment and estimated their level of efficiency (shown in the following parameters: pH, color, turbidity and coliform count), present in the specialized literature. To this end, we reviewed academic works that researched the use of techniques for disposal, filtration and contamination of rainwater as an alternative to improving its quality. We noted that the same technique can present different results, according to the different initial conditions for the treatment, such as: quality of the precipitated water, quantity discarded in the first flush, materials used as filtration media and treatment flow rate. The non-standardization of studies about the analyzed parameters proved to be a factor that makes difficult comparison and analysis of results. We found that the techniques/processes involved in this study removed contaminants present in rainwater efficiently. Depending on the initial quality of the water and the specifics of its intended purpose, the treatment can be conducted more or less rigorously, and drinking water should always go through a disinfection process to eliminate the concentration of pathogens present in its content.