Polimento do efluente de uma série de lagoa de estabilização usando membranas filtrantes

Abstract

The use of filter membranes is increasingly applied in various industrial application. Among the types of filter membranes, one can highlight that of ultrafiltration, which is widely used in post-treatment sewage sectors.The present work had as objective to verify the efficiency of ultrafiltration membranes in the effluent polishing of a series of stabilization pond for the production of permeate with high purity.The ultafiltration membrane analysed was Polyethersulfone (PES) of German origin. PES was coupled to a post-treatment system. The effluent obtained an initial biological treatment in stabilization ponds (two series anaerobic ponds and one facultative pond) at the Sewage Treatment Station (ETE) of Companhia de Água e Esgotos da Paraíba (CAGEPA). In the post-treatment the effluent passed through sand and screen filters, followed by addition of coagulant. Soon afterwards it was submitted to a filtration process with PES membranes. The effluent was collected and stored for the own use of the pilot plant station. The effluents from the stabilisation ponds and the permeates were collected and sent to the laboratory analysis of COD (Chemical Oxygen Demand), turbidity, pH, ammoniacal nitrogen, absorbance and thermotolerant coliforms. At the end of the experiment, excellent values of thermotolerant coliforms, COD, turbidity and absorbance were obtained.