Quality Analysis of Atmospheric Deposits in Networks with Intermittent Service

Abstract

In Latin America, the installation of atmospheric reservoirs is frequent due to various policies related to water availability and management. This type of infrastructure, in addition to modifying the hydraulic behavior of the network, significantly alters water quality, conditioning its microbiological characteristics and exposing the user to health problems. The hydraulic characterization of reservoirs has been widely approached in terms how their filling/emptying cycles are reproduced; however, several factors have not been taken into account – those which modify the disinfectant concentrations in the reservoirs, either improving or impairing the water quality. In the present work, the Epanet Toolkit model is developed and applied to analyze loss in the quality of the water in the tanks as an effect of chlorine concentrations available in the main network and based on different intradomiciliary hydraulic peculiarities such as the change in the pattern of demands, the variation of the regulation volume, the operation of the valve that controls the level in the cisterns, among others.


Keywords: atmospheric deposits, water quality, intermittent networks.


Resumen


En América Latina es frecuente por diversas políticas referentes a la disponibilidad y gestión del agua, la instalación de depósitos atmosféricos. Este tipo de infraestructuras, además de modificar el comportamiento hidráulico de la red, alteran significativamente la calidad del agua condicionado sus características microbiológicas y exponiendo al usuario a problemas de salubridad. La caracterización hidráulica de los depósitos ha sido ampliamente abordada desde el punto de vista de la forma en la cual se reproducen sus ciclos de llenado/vaciado, sin embargo, no han tenido en cuenta diversos factores que modifican las concentraciones de desinfectante en los depósitos, ya sea que promuevan un post mejoramiento o un empobrecimiento de esta, en términos de calidad. En el presente trabajo, se desarrolla aplica el modelo del Toolkit de Epanet para analizar la pérdida de calidad del agua en los depósitos en función de las condiciones de concentración de cloro disponible en la red principal y en base a distintas peculiaridades hidráulicas intradomiciliarias como son el cambio en el patrón de demandas, la variación del volumen de regulación, la forma de operación de la válvula que controla el nivel en las cisternas, entre otras.


Palabras Clave: depósitos atmosféricos, calidad del agua, redes intermitentes.

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