Relação entre parâmetros de qualidade da água e a concentração de cloro residual livre em um setor de abastecimento de água em Ponta Grossa - PR

Abstract

Water quality, as well as its maintenance throughout the distribution system, is a constant concern of management entities. The disinfection of water with chlorine is one of the most used methods in the treatment of water destined for public supply, which has the advantage of maintaining a residual. However, the residual chlorine present in the treated water reacts throughout the distribution system, leading to its decay. The present work consisted of studying the relationship between water quality parameters and the concentration of free residual chlorine at different distribution network points, in the Los Angeles supply sector, held in the city of Ponta Grossa - PR, Brazil. Seven samples were collected weekly at seven distribution points during the period from October of 2018 to September of 2019 by analyzing the parameters of free residual chlorine concentration, turbidity, apparent color and the presence or absence of Total Coliforms. The results showed that the water quality parameters analyzed at the monitored collection points comply with Consolidation Ordinance nº 5 of the Ministry of Health of September 28, 2017. Variance analyzes were performed for the parameters free residual chlorine and turbidity. The results showed that there is a reduction in the concentration of free residual chlorine proportionally throughout the distribution system as the points move away from the water treatment plant. They also show that there is a tendency towards an increase in turbidity throughout the distribution system in places where the network is made of iron and is closer to reaching its useful life.