ABSTRACT
The objective of the present investigation is to evaluate the influence of two coagulants, an inorganic and natural (PAC and tannin), in the treatment of effluent from pig slaughtering. Both coagulants were prepared in aqueous solution, 1% (v/v) to the PAC and 0.5% (w/v) to tannin. To evaluate the effect of coagulants in the effluent, coagulation/flocculation assays were performed using the jar-test apparatus. The dosages evaluated for both coagulants were 50, 100, 150, 200, 250 and 300 mg L−1. The parameters analyzed were color and turbidity. According to the results of the statistics analysis, the optimal dosage obtained for both coagulants was 250 mg L−1. With these dosages, it was observed turbidity and color removals higher than 94% and 85%, respectively, with residuals less than 40 NTU for turbidity and 400 uH for color, indicating with this optimal dosage best results mainly when tannin is used as coagulant.
