Tratamento de efluente de uma indústria de curtume localizada na região metropolitana do Rs por eletrofloculação

Abstract

The tannery industry is one of the main sectors of the Brazilian economy, however it is con-sidered highly polluting due to the complexity of the effluents generated in the production processes due to the high content of organic matter, solids, oils and greases, chromium, among others. So, this study aims to evaluate the efficiency of electroflocculation (EF) treat-ment with the use of aluminum electrodes by removing the dependent variables apparent col-or, turbidity and Chemical Demand of Oxygen (COD) under different conditions of the inde-pendent variables: electrical current, treatment time and distance between the electrodes. The experimental design was 2³, including 6 tests at the axial points and 3 tests at the central point, according to the Rotational Central Compound Design (DCCR), totaling 17 trials. Through ANOVA, the influence of the independent variables on the maximum removal of the depend-ent variables was confirmed with 95% reliability. The overall desirability function determined an optimized condition with current of 3.99 A, treatment time of 4.8 min and distance be-tween the electrodes of 6.52 cm, whereby a removal of 94.2% of the apparent color was achieved, 94.3% for turbidity and 74.02% for COD, which reinforces the viability of EF as a tanner wastewater treatment technology.