Dimensionamento de reservatório para aproveitamento de água de chuva: comparação entre métodos da ABNT NBR 15527:2007 e Decreto Municipal 293/2006 de Curitiba, PR

Abstract

Este estudo avaliou a viabilidade do aproveitamento da água das chuvas no Tanque de Provas, utilizado em ensaios de modelos reduzidos de embarcações da Faculdade de Tecnologia de Jahu-Fatec Jahu, SP. O trabalho considerou os dados pluviométricos locais, a área de cobertura para captação e a demanda de água. Foi estimada a necessidade de água no processo de limpeza por filtragem, lavagem e evaporação do Tanque de Provas. O dimensionamento do reservatório foi calculado conforme as metodologias descritas na NBR 15527, que determina os requisitos para o aproveitamento de coberturas em áreas urbanas para fins não potáveis. O volume do reservatório selecionado como a melhor alternativa após as análises comparativas considerou as restrições locais e o risco de não atendimento, permitiu o máximo aproveitamento da água pluvial e resultou na maior redução possível da demanda de água potável do sistema de abastecimento público. Palavras-chave: captação de água pluvial, não potável, índice pluviométrico. ABSTRACT This paper explores the possibility of harvesting rainwater in a Testing Tank used to test scale models of boats and ships in Jahu College of Technology, São Paulo State. We considered local rainfall data, the coverage area for catchment and the demand for water. Water demand was estimated for cleaning, filtering and evaporation processes in the Testing Tank. The dimensions of the reservoir were calculated according to the methodologies described in the NBR 15527, which prescribes the requirements for the use of roofs in urban areas for the catchment of rainwater for non-potable purposes. The volume of the reservoir selected enabled the best use of rainwater and resulted in a better reduction of water demand on the public supply system. It was chosen as the best alternative after comparative analysis considering the local restrictions and the risk of non-compliance.

Análise de viabilidade técnica e econômica do uso de água de chuva em uma indústria metalmecânica na região metropolitana de Curitiba PR

“…For the dimensioning of the reservoir were used the NBR 15527/2007 ABNT, 2007) recommendations dealing with covering requirements in urban areas for non-potable purposes. The NBR 15527/2007 contains six methods for sizing of rainwater reservoirs presented in the Annex; such methods are described in that NBR and detailed in Bezerra et. al.…”

“…According to Bezerra et al (2010) in Australian Practical Method, the reservoir volume (V R ) is determined by attempts to meet the demand with system trust between 90 and 99%, as recommended by the NBR 15527/2007(ABNT, 2007. According to the equations indicated in the standard, and considering the period of a year that was investigated in these case studies, the container shall meet the demand for at least 11 months a year, to get reliability of 91% (Equations 6 and 7) .…”

Rainwater Harvesting in Buildings in Brazil: A Literature Review

“…As per Bezerra et al [87], reliability is the relationship between the period in which demand is met with rainwater and the total investigated period, and efficiency is the relationship between the volume of harvested rainwater and the volume of rainwater that did not overflow from the tank. Therefore, reliability is related to the verification of the service to the demand, and efficiency is related the impact of the rainwater harvesting system on runoff.…”

“…Although the Brazilian standard on rainwater usage in buildings presents six methods for tank sizing, there are criticisms about them, such as the fact that the results presented by them are very different from each other [87]. According to Dornelles [39], the practical methods in the standard are those that present greater limitations since they adopt ratios of simple proportionality between rainfall and tank capacity, i.e., they do not take the seasonal behaviour of rainfall into account.…”

Aproveitamento de água de chuva de cobertura em edificações: dimensionamento do reservatório pelos métodos descritos na NBR 15527

“…O dimensionamento do reservatório é o maior desafio para viabilizar o aproveitamento das águas pluviais, pois é, na maioria dos casos, o item mais caro do sistema (Bezerra et al, 2010;Cohim e Oliveira, 2009;Cohim et al, 2008;Mierzwa et al, 2007;May, 2004;Martinson e Thomas, 2009).…”