Balanço de massa dos resíduos de uma ETA de filtração direta

Abstract

In Brazil, part of the water treatment plants (WTP) dispose of their waste directly in water bodies, without any form of treatment. In the Brazilian Northeast, the use of direct filtration technologies is quite frequent, in which practically the only waste from the WTP is the filter washing water. Thus, the present work aims to elaborate a script of the mass balance of a WTP of direct filtration in line that treats the water of a coastal lagoon with low turbidity, moderate color and typically oligotrophic trophic state, with low concentrations of algae and cyanobacteria. From this, in addition to providing alternatives for the treatment of waste generated by WTPs, there is the possibility of subsidizing future projects. To this end, bibliographic research was carried out to obtain the data from the WTP under study and, subsequently, a mass balance was carried out based on the guidelines of Ferreira Filho (2017). Therefore, it was possible to quantify the solids from the raw water and the solids from the coagulant, as well as to calculate the mass of solids that could not be released into the water body. A sludge production at the WTP of approximately 1,690 kg/day was estimated. In addition, it was also possible to determine the sludge generation at each stage of the treatment process.