Tratamento de efluente de cervejaria artesanal por ozonização

Abstract

Beer is one of the most consumed beverages by Brazilians, and, over the last few years, craft beers have been standing out in the brewing market for having unique characteristics, expanding the microbrewery market. Due to this constant growth, the need to adapt these micro-companies to the legislation for the correct purposes of effluent treatment is intensified, since the residues generated by these companies have considerable amounts of organic matter. Among the alternatives for effluent treatment, ozonation stands out, acting as an advanced oxidative process with the advantage of performing a treatment that educes the percentage of organic waste, in order to avoid environmental liabilities. For this work, we evaluated the treatment of a sample of brewery effluent, collected from a craft brewery, by ozonation in acid (4.0), basic (10.0) and neutral (7.0) pH, in times of 0, 5, 10, 15, 20, 25 and 30 min of exposure to O3, through physical-chemical parameters, such as color, turbidity, chemical oxygen demand (COD) and ammoniacal nitrogen, the experiment was carried out in a jar test and Erlenmeyer. Also, the values of the kinetic constants of color reduction and COD were determined. The effluent sample treated by ozonation at basic pH (10.0) resulted in a better efficiency when compared to the other pH ranges, showing a reduction of 91.6% for turbidity, 82% for color, 41% for COD and 88 % for ammonia nitrogen. The value obtained for the first order kinetic constant for color was 0.055 min-1 and the value of the second order kinetic constant for COD was 3.93 x 10-5 min-1. The results obtained from the analyzes performed are consistent with the results reported in the literature, both for the characterization of the raw effluent and for the values obtained after the treatment performed.