Relações entre a qualidade da água de reuso produzida a partir de águas cinzas e a sua percepção por parte dos usuários

• Autor(a) principal: Belisário, Graciele Zavarize
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/10891
• topic: Reuse; Regrowth; Perception; Greywater; Reuso; Recrescimento; Percepção; Água cinza; Engenharia Sanitária; 628

Concerns about the presence of pathogenic microorganisms in reuse waters are one of the impediments to the greater acceptability of this practice in urban centers. Therefore, many parameters of water quality are monitored to ensure the quality required for reuse, and turbidity is one of the most used. Thus, this study sought to analyze the relationships between the quality of the reuse water produced from gray water and its perception by the users. Through a statistical correlation analysis with data from several studies, this research showed that between gray water and sewage samples, there is a moderate correlation between the turbidity values with the presence of Escherichia coli. (E. coli). Therefore, in statistical terms, there is no strong and significant correlation between turbidity and E. coli in wastewater, concluding that not always high turbidity values must necessarily represent a higher value of indicator microorganisms. In terms of characterization of the samples, the gray water quality was very similar to those reported in the literature. Here, a COD / BOD ratio in the raw gray water (ACB) of 1;1, was obtained, which indicates a high biodegradability of this effluent. The treated gray water quality (ACT) is in compliance with the parameters presented in the standard "Alternative sources of non-potable water in buildings" released for public consultation by ABNT. In addition, this study showed that there are possibilities of E. coli regrowth in ACB and ACT under different concentrations of residual chlorine. There was up to 2 logs regrowth of E. coli at the time that the residual chlorine was above 2 mg Cl2/L. This result can be explained by the fortification of samples with nitrogen and phosphorus and inoculation of microorganisms, large chlorine consuming agents. Finally, organoleptic tests for the perception of the quality of gray water with different levels of turbidity showed that the samples with lower turbidity were more naturally accepted. However, among the samples with higher levels (8 NTU and 10 NTU), there was no difference. However, for non-potable purposes, considering 3 NTU gray water samples as a comparative basis, the judges were only able to perceive the difference when the comparison was made with a sample of 10 NTU.