Potabilização de água da chuva por ultrafiltração

Abstract

The depletion of water resources is occurring in fast speed and reaches surface and ground sources, compromising the quality of water supply for public supply in many places. Rainwater is an easily capture resource and a promising alternative for this problem, since it has considerable quality, but does not meet the parameters established to classify it as drinking water, requiring treatment to achieve the quality required. Separation processes with membranes are an alternative to improve water quality. The aim of the work was to use the ultrafiltration for the treatment of rainwater, adjusting their physicochemical and microbiological parameters for the drinking water quality.Two UF membranes were tested at two different pressures to treat the rainwater collected in a building of the University of Passo Fundo. Rainwater showed a moderate concentration of suspended solids, color, turbidity, organic matter and coliform contamination and a low concentration of nitrites, nitrates and sulfates. The two UF membranes used (with molecular weight cutoff of 4 kDa and 50 kDa) allowed the adjustment of these parameters to the potability, and the permeate flux of hollow fiber (50 kDa) membrane was above 130 L.h-1.m-² (at 2 bar). Therefore, rainwater harvesting and its UF is a promising alternative for a decentralized supply of drinking water