Avaliação da qualidade da água de chuva em Maceió/AL coletada em telhados: tratamento através de filtração lenta e possíveis utilizações

Abstract

The rainwater has been used in various locations around the world, as na alternative source to supply the water demand, thus the characterization of parameters for its quality is of paramount importance for delineating this activity. This study sought to determine the quality of rainwater collected in roof with 45cm and 15cm for the support layer. We conducted a statistical analysis comparing data between two different stages of evaluation of rainwater. The results show that some parameters showed a significant difference between them. The analysis results of water quality of rain showed that some physical-chemical and microbiological parameters not all fit within the limits established by Ordinance of the Ministry of Health 518/2004 and is therefore not suitable for direct human consumption, however, may be harnessed for industrial boilers and as cooling water. The results of the operation of the slow filter showed that the filter media showed fine particles that interfere with the results of turbidity and color, in addition, rain water in the filter output showed an improvement in their quality of microbiological parameters, however, without reaching the levels for those indicators, established by Brazilian legislation for drinking water.ceramic tiles, stored in a fiberglass tank in the city of Maceió / AL in two different periods, by monitoring the physical, chemical and microbiological. Moreover, to evaluate the performance of slow sand filtration to treat stormwater, with emphasis on parameters that do not meet the standard for drinking water law in Brazil, Decree 518/2004 of the Ministry of Health Research hás developed a system of catchment and reservoir of rainwater, which went through a pilot system of slow sand filtration with downward flow. In the characterization of rainwater samples were obtained from the storage reservoir, in two stages, before the slow sand filtration and during operation of the slow filter. The samples to assess the efficiency of slow sand filters were collected in the reservoir (input), two intermediate points along the filter bed and the filter output. The slow filter is built in a cylindrical barrel of polypropylene with 90cm height and 56cm in diameter and thickness of the filter bed of