Uso de polímero como auxiliar de sedimentação ETA Castelo Branco

Abstract

Currently, the water supply service for the population faces several challenges, including the worsening of the quality of raw water with industrial and domestic discharges into water bodies, without adequate control and treatment, and the increase in the population's need for consumption. That grows in an unplanned way. Faced with these issues, sanitation concessionaires must seek alternatives to maintain the quality of treated water within the standards established by ordinance 888/21 of the Ministry of Health and always aim to optimize processes in order to reduce consumption of chemical products. The present work was developed at ETA Castelo Branco, which has a nominal capacity of 4,000 L/s and is currently operating at 3,200 L/s. The unit has a high consumption of coagulant and presents difficulty in adjusting the filtered turbidity below 0.5 NTU, in addition, in times of drought in the water sources, it presents high levels of Iron and Manganese in the raw water. The ETA has conventional treatment consisting of the stages of coagulation (with aluminum sulfate), flocculation (mechanical flocculators), decantation (the first stage being conventional decanters and the second stage being modular decanters), filtration (with descending filters) and disinfection (with chlorine). In addition to the processes described, alternatives are sought to increase the efficiency of the unit, such as the use of polymer as a sedimentation aid, in order to reduce the turbidity of the settled water, the consumption of chemical products and increase the iron and manganese removal rate.