Utilização de processos de separação com membranas para purificação e reúso da água de lavadoras de roupa

Abstract

Laundering processes demand large amounts of water. The resulting wastewater may contain components from the composition of softeners and liquid or powdered detergents, consisting predominantly of surfactants, cotton fibers and particulates. The wastewater generated, when treated, can be reused, even in the washing process itself, reducing the requirement for potable water and minimizing scarcity problems in urban areas. Amongst the promising alternatives, membrane processes can be highlighted as environmentally responsible processes, producing water free of microorganisms, contaminants and particulate matter. In the present work, Microfiltration, Nanofiltration, Reverse Osmosis and coagulation were studied as treatment alternatives for the effluent in analysis. Through the characterization of individual solutions and membranes, the SR90 Nanofiltration membrane was selected, for its higher hydrophilicity. Subsequently, performance tests of the process selected were carried out in order to assess the quality of the effluent produced by these processes. Submerged Microfiltration + Nanofiltration was the most promising combination for the reuse of this water in terms of quality and process, producing an effluent with COD of ± 8 mgO2/L e TOC of 18 mgC/L, besides a real effluent flux 74% higher when compared to the direct Nanofiltration flux.