Viabilidade técnica e econômica de implantação de um sistema de aproveitamento de água pluvial no Campus Sertão da Universidade Federal de Alagoas

Abstract

The rainwater is an abundant source and easily accessible. The use of rainwater harvesting systems has several positive aspects, because it is possible to reduce the potable water consumption, reducing water supply costs, minimizes the risk of floods and preserve the environment by reducing the scarcity water resources. Face of this context, this present study aimed to study the technical and economic viability through of implementation of a rainwater harvesting system, for non-potable water purposes, in the Sertão Campus of the Universidade Federal de Alagoas, located in the city of Delmiro Gouveia-AL. The first step was to conduct a survey of water consumption by users and sanitary appliances, analyzing building documents and water bills provided by university and, furthermore, to develop a calculation algorithm for dimensioning the reservoir. Through data obtained from questionnaires applied on a samples of users, it was possible to estimate the university's water consumption profile from the values of frequency and time of use of the sanitary appliances. After minimizing errors of consumption values through sensitivity analysis, it was possible to estimate the distribution of water use at the university, including non-potable water. The found water demand was then adjusted from the results obtained by dimensioning algorithm. Has been verified the need to reduce the demand, due to unavailability of water resources to supply all non-potable demand. Thus, it was then possible to estimate the volume of the reservoir. The next step was to scale the rainwater conductive elements and perform economic analysis of the process. With the implementation of rainwater harvesting system should be a reduction of approximately 24.0% in the potable water consumption. Through this study, it was verified that the implementation of a rainwater harvesting system at the university presented itself technically and economically viable, because the total cost of implementation was estimated at R$ 109,188.84, with a return time of investment of 4 years and 11 months.