Use of the activated sludge system for treatment of effluents from the mushroom pickle industry

Abstract

In this work, the treatment of a mushroom pickle effluent through the process of activated sludge in a continuous system was evaluated. The variables COD, turbidity and pH responses were evaluated, as well as the monitoring of the TSS concentration in the reactor. In the first 12 days of operation there was a strong COD variation in the final effluent, obtaining removals < 90%, after this period, the removals increased, reaching removals > 97%. The values obtained from TSS in the reactor are closer to the conventional activated sludge variant, presenting values from 2198 to 3620 mg L^-1 from the 6th day to the 24th day of operation. The percentages of turbidity removal practically remained in the range of 50 to 82%. The initial pH values (reactor input) at the beginning of the activated sludge process ranged from 2.9 to 5.2. However, the final pH values, that is, at the outlet of the secondary settler, remained in the range of 6.8 to 8.0, very close to the recommended range of operation.