Caracterização das águas do Canal do Mangue: diagnóstico e propostas

Abstract

Mangue river channel is an important water body located in the central area of Rio de Janeiro, which is the recipient of some local rivers, rain water and other contributions. The channel is partially located in an urban area that is being transformed in the context of Porto Maravilha project. The water of the channel flows to the Guanabara Bay, a system environmentally fragile. This work aims to characterize channel waters, through previous diagnosis and to propose alternatives of physical-chemical treatment. Four sampling campaigns were conducted during a year in five selected points of the channel in order to investigate the water quality. For one selected point two additional sampling campaigns were performed to conduct a study of physical-chemical treatment of the water aiming reuse. The results indicate that for most analyzed parameters the water quality can be considered unsatisfactory, resulting in Poor WQI of between 20,7 and 25,7 according to INEA. On the other hand, the utilization of a simple water treatment process can produce water for reuse in some non-potable applications, such as street and square washing, since it was possible to remove turbidity, true color and fecal coliforms, besides reducing 88% of the gross COD at a concentration of 25 mg L-1 FeCl3 in the flocculation/ coagulation processes. And even comes into compliance with regulatory limits non-potable nationally and internationally deliberate. In addition, observations were made about the state of conservation of the water channel and proposals were made to enhance the channel operation.