Comparativo de eficiência entre métodos de pós tratamento para o efluente de uma estação de tratamento de efluentes de uma indústria automobilística

Abstract

The ambiental concern around the irregular discard of effluents has grown gradually over the last few years, since the consequence of this irregular discard are catastrophic to several spheres of a hydric ecosystem, and can even fatally affect human beings. With the intent of minimize this irregular disposal, several regulations are being revised, and for the already existent Effluent Treatment Stations attend the revised grants, adjusts are necessary on these places, among which may even be the implementation of new stages in the treatment process. Of these processes, the Electrocoagulation and Process Fenton stand out. To compare the efficiency of carbonaceous organic matter removal in terms of COD between the mentioned processes, the effluent was collected in an automobile industry in the metropolitan region of Curitiba, characterized and subsequently tested 3 batch samples for each process. The Fenton treatment was carried out using hydrogen peroxide and iron sulphate as reagents, in quantities of 15 g.L-1 and 1 g.L-1. For Electrocoagulation, tests were carried out with aluminum and iron electrodes, under constant voltage of 12V. The processes had a reaction time of 1 hour and were carried out under constant agitation. After trials, the COD was read to find out the respective removal rates for each treatment. After analysis, it was found that, for the analyzed effluent, the COD removal efficiencies were 54, 48 and 53% for the Fenton, Electrocoagulation with aluminum electrodes and Electrocoagulation with iron electrodes treatments, respectively, in relation to the raw effluent, whose COD was 49.8 mg.L-1. In conclusion, both processes have similar efficiency, só that is necessary to analyze other factors that were not contemplated on this study to select a treatment to be implemented, like cost of implementation and operation.