ESTUDO DA DOSAGEM DE COAGULANTE NATURAL NO TRATAMENTO DE ÁGUA COM ELEVADA CARGA DE SÓLIDOS E TURBIDEZ

Abstract

The coagulation step is essential for a water treatment plant. Therefore, this work aims to evaluate the dosage of coagulant in the treatment of surface water according to the flood pulse of the Amazon River. Samples were collected at two points on the left bank of the Amazon River, in the old and new harbors of the municipality. The following parameters of electrical conductivity, pH, temperature, turbidity, real and apparent color, total suspended solids, total alkalinity and optimal dosage were analyzed using the Jar Test device. In this project, the natural coagulant Tanfloc SG was used to find the optimal dosage. Five jars of 1 L to 2 L were used, with concentration variations from 0 to 12 g/L of coagulant. Physicochemical parameters over the periods were electrical conductivity 24.70 to 30.83 µS/cm; pH 6.19 to 8.00; temperature 27.37 to 32°C; turbidity 28.83 to 223.67 UNT; real color 36.91 to 199.33 mg Pt/L and apparent color 212.88 to 500 mg Pt/L; total suspended solids 10 mg/L to 160 mg/L; total alkalinity 24.70 to 39.90. During the periods, there were changes in the dosage of coagulant. It was concluded that the Amazon River obtains physicochemical variations over the periods, as well as the amount of coagulant concentration for water treatment, showing efficiency for the removal of color and turbidity.