2023 年 48 巻 1 号 p. 49-53
Contamination of portable water source with organic micropollutants have increasingly recognized as a potential risk for the human health. Such contaminants include pesticide, herbicide, medicines, PFAS (per– and polyfluoroalkyl substance) and so on. These organic micropollutants could be removed by conventional spiral wound nanofiltration (NF) technology, however, it often requires extensive pretreatment, thus had to increase greenhouse gas emission in the entire treatment process while solving human health issue. In order to solve this dilemma, direct nanofiltration (dNF) technology has been developed. The hollow fiber dNF membrane, with the patented polyelectrolytes based layer by layer technology, was tested with actual surface water that contains micropollutants. For most of the micropollutants including PFAS, the dNF permeate showed below detection limits, which was not possible with conventional hollow fiber UF/MF technology due to their larger pore size. The same dNF membrane was operated in a commercial plant in Dumai, Indonesia for humic acid removal. The membrane have exhibited stable operation for one and half a year.